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PRESENTED BY

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THE

VOYAGE OF H.M.S. CHALLENGER.

ZOOLOGY--VOL. XVIII.

SECOND PART.

REPORT

ON THE

SCIENTIFIC RESULTS

OF THE

VOYAGE OF H.M.S. CHALLENGER

DURING THE YEARS i873-76

UNDER THE COMMAND OF

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AND THE LATE

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ZOOLOGY— VOL. XVIII.

SECOND PART

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CONTENTS.

EEPORT on the RADIOLARIA collected by H.M.S. CHALLENGER during the years

1873-1876.

By ERNST HAECKEL, M.D., Ph.D., Professor of Zoology in the University of Jena.

SECOND PART.— OSCULOSA.
(NASSELLARIA AND PH^EODARIA.)

CONTENTS.

SECOND PART.

PAGE

II. Subclass OSCULOSA, ... 889

Legion III. NASSELLARIA vel MONOPYLEA, . 889

Order 11. NASSOIDEA, .... 895

„ 12. PLECTOIDEA, . . . 898
,, 13. STEPHOIDEA, .

„ 14. SPYROIDEA, .... . 1015
„ 15. BOTRYODEA, .

„ 16. CYRTOIDEA, ... 1126

Legion IV. PH^ODARIA vel CANNOPYLEA, . 1521

Order 17. PH.EOCYSTINA,

' „ 18. PH^EOSPH^ERIA, . . 1590

„ 19. PHJEOGROMIA, . !642

„ 20. PH.EOCONCHIA, . ^710

NOTE ON THE DIMENSIONS AND MEASUREMENTS, . . 1760

ADDENDA, . 1761

EKRATA, . !763
INDEX, .

REPORT ON THE RADIOLARIA. 889

Legion III. NASSELLARIA,
vel Monopylea, vel Monopylaria (Pis. 51-98).

Nassellaria (inclusis Spyridinis), Ehrenberg, 1875,

Monopylea, Hertwig, 1879.

Monopylaria, Haeckel, 1881.

Oyrtida et Acanthodesmida, Haeckel, 1862,

Definition. — Kadiolaria with simple membrane of the central capsule, which
is monaxon or bilateral, and bears on one pole of the main axis a porous area
(porochora), forming the base of a peculiar intracapsular cone (podoconus). Extra-
capsulum without phseodium. Skeleton siliceous, very rarely wanting. Fundamental
form originally monaxon, often dipleuric or bilateral.

The legion NASSELLARIA vel MONOPYLEA, in the extent here denned, was constituted
in 1879 by Richard Hertwig in his work Der Organismus der Eadiolarien
(pp. 133-137). He gave to this large group the rank of an order, and united in it the
two families Acanthodesmida and Cyrtida, which I had constituted first in 1862 in
my Monograph (pp. 237, 265, 272); but he added, too, as a third family the
Plagiacanthida, united by me with the former. In the first system of Ehrenberg (1847,
loc. cit., pp. 53, 54), four families belonging to the MONOPYLEA were enumerated, the
Halicalyptrina, Lithochytrina, Eucyrtidina, and Spyridiiia. He united the three former
under the name." Polycystina solitaria," which he afterwards changed into NASSELLARIA
(1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 157).

In my Monograph of the Radiolaria (1862, pp. 265—345) forty -four genera of
NASSELLARIA were enumerated (six Acanthodesmida and thirty-eight Cyrtida), whilst
the total number of genera in the whole class of Radiolaria at that time amounted to
one hundred and thirteen. But owing to the astonishing number of new and interesting
forms of this legion which I afterwards detected in the collection of the Challenger,
in 1881 I distinguished in my Prodromus not less than three hundred and seventeen
genera. These were disposed in five large main groups, retained in the present Report,
with twenty -six families, viz., (1) Plectoidea (with three families), (2) Ste-
p h o i d e a (with four families), (3) Spyroidea (with four families), (4) Botryodea
(with three families), and (5) Cyrtoidea (with twelve families). The first two
groups have an incomplete or rudimentary skeleton, and may be united in the order
Plectellaria, whilst the other three families possess a complete latticed shell, and

(ZOOL. CHALL. EXP. — PART XL. 1885.) Rf 112 ^

890 THE VOYAGE OF H.M.S. CHALLENGER.

may be united as Cyrtellaria. The former correspond to the Acanthodesmida,
the latter to the Cyrtida in my Monograph.

The character common to all MONOPYLEA or NASSELLARIA, which separates them from
all other Eadiolaria, was first recognised by Eichard Hertwig in 1879, and consists in
the singular structure of the monaxonian central capsule, bearing on the basal pole a
peculiar porous area or operculum, the " Porenfeld;" we call it shortly the " porochora."
It represents a circular or elliptical porous plate on the basal pole of the vertical main
axis of the central capsule, and bears a peculiar " podoconus " or " Pseudopodien-Kegel,"
a conical body of singular structure, protruding inside the membrane into the capsule.
The pseudopodia arising from this peculiar " podoconus " proceed from the capsule
piercing the " porochora," whilst the other parts of the capsule are not perforated.

The MONOPYLEA are therefore " Merotrypasta," like the following fourth legion, the
PH^EODARIA or CANNOPYLEA. But in these latter we find on the basal pole of the
monaxonian capsule only one single large main opening, prolonged into a peculiar tube,
and there is no trace of the typical " podoconus," characteristic of all NASSELLARIA.
The latter agree, however, with the former in the possession of a basal opening, serving
for the emission of the pseudopodia, and in the monaxonian fundamental form, arising
from this structure. Therefore these two legions of " Merotrypasta " exhibit a wider
divergence from the ACANTHARIA and SPUMELLARIA, the two legions of " Holotrypasta,"
in which the central capsule is everywhere perforated by innumerable small pores (com-
pare above, pp. 5, 6, 716).

The Skeleton in all NASSELLARIA consists either of pure silica, or of a peculiar
silicate ; never of acanthin (as in all ACANTHARIA). The siliceous bars and beams
constituting it are invariably solid (as also in the SPUMELLARIA) ; never hollow
(as in the PH^ODARIA). In the small family of Nassellida alone (with the two
genera Cystidium and Nassella) the skeleton is entirely absent. In all other genera
of NASSELLARIA the siliceous skeleton is more or less developed ; imperfect, or quite
rudimentary in the Plectellaria (Plectoidea and Stephoidea), but
perfect and forming a regular lattice-shell in the Cyrtellaria (Spyroidea,
Botryodea, and C y r t o i d e a). The different forms of this skeleton exhibit an
extraordinary variety, but may be reduced to a few very simple fundamental forms, or
even to a single, most simple original form. The comparative morphology is more
interesting, but also more difficult to understand than in any other Eadiolaria.

The geometrical fundamental form of the skeleton is in all NASSELLARIA monaxonial,
the vertical main axis of the body, which is already indicated by the axis of the central
capsule with two different poles, being also expressed constantly in the form of the
skeleton. The lower or basal pole of the latter always exhibits a different shape from
that of the upper or apical pole. This difference is so striking in nearly all MONOPYLEA,
that the two poles may be determined on the first view.

REPORT ON THE RADIOLARIA. 891

In the great majority of NASSELLARIA not only is the monaxonial fundamental form
expressed, but also the dipleuric or bilateral, so that the symmetrical halves of the body
may be easily determined ; the right and left halves exhibit the same symmetry as in
the vertebrates, so that we may distinguish an anterior ventral and a posterior dorsal
face of the body. The whole form is in this case determined by three dimensive axes,
perpendicular to one another, two of which are heteropolar, the third is homceopolar.
The apical pole of the vertical main axis (principal or longitudinal axis) is different
from the basal pole. The ventral pole of the horizontal sagittal axis (or dorso-ventral
axis) is different from the dorsal pole. The right pole of the horizontal transverse axis
(lateral or frontal axis) is equal to the left pole. Therefore the sagittal or median plane
of the body (in which the principal and the sagittal axis are crossed) divides it into
symmetrical equal halves and is perpendicular to the frontal axis.

Three different original elements of structure are recognisable in the majority of
NASSELLARIA, viz., (l) a vertical simple ring, the primary or sagittal ring, placed
vertically in the sagittal plane and enclosing the median plane of the central capsule ;

(2) a basal tripod, composed of three diverging radial rods, which are united on the
basal pole of the central capsule and are either expanded horizontally or descend ;

(3) an ovate or subspherical, simple lattice-shell, the cephalis or capitulum, which sur-
rounds the central capsule and exhibits a peculiar structure on its basal pole.

These three important original elements of structure — the sagittal ring, the basal
tripod, and the latticed cephalis — are so united in the majority of NASSELLARIA that the
cephalis rests upon the tripod and includes the sagittal ring wholly or partially. The
simplest realisation of this typical union is afforded by the Archiperida and Tripospyrida,
and these may be derived from the simpler important Stephanid Cortina (PL 83, fig. 9 ;
PI. 92, fig. 21 ; PL 97, fig. 1). In this and in all other tripodal NASSELLAEIA, the three
basal rods or the " cortinar feet " are constantly so arranged that an odd or posterior rod,
the " caudal foot " (c) is opposed to the two anterior paired rods, the " pectoral feet "
(one right, p", and one left, p']. The caudal foot lies in the sagittal plane, and is
prolonged upwards into the dorsal rod of the sagittal ring (V), and over this in a free
ascending spine, the " apical horn " (a). The curved ventral rod of the ring (r) is
united above with the base of the apical horn, below with the common centre
of the tripod or the " cortinar centrum." The characteristic position of the central
capsule in this skeleton of Cortina is such that its basal pole (with the porochora)
rests upon the centre of the tripod, whilst its sagittal perimeter is separated from the
surrounding ring by the calymma ; the numerous pseudopodia arising from its base
diverge downwards and are supported and protected by the three basal feet of the
tripod (PL 97, fig. 1). Compare also Pis. 51, 53, 84, 95, 98.

The typical skeleton of Cortina, a tripodal ring, becomes more developed in the
Semantid Cortinisciis, in which the basal parts of the three diverging feet are united

892 THE VOYAGE OF H.M.S. CHALLENGER.

by a second horizontal ring, the cortinar or basal ring (PI. 92, figs. 11-13). The pores
between the former and the latter, or the " cortinar pores," may be regarded as the first
beginning of the lattice -plate, composing the " cephalis " or the simple primordial shell
in the Archiperida and Tripospyrida, and transmitted from these by heredity to the
great majority of NASSELLARIA.

The "cephalis or capitulum " (the "Kopfchen" of the German authors) is therefore
the most important part of the skeleton in all C y r t e 1 1 a r i a, or in all NASSELLARIA
possessing a complete lattice-shell. In the Plectellaria, however, or in those
NASSELLARIA which do not possess a complete fenestrated shell, the " cephalis " is either
imperfect or totally wanting. The cephalis surrounds the enclosed central capsule on
all sides in the form of an ovate or subspherical lattice -shell, and is separated from it only
by the jelly-like calymma. The sagittal ring is either enclosed in the wall of the cephalis
(wholly or partially), separating its two lateral halves, or it is enclosed in the cavity of
the cephalis and connected with its sagittal perimeter by short beams. The base of
the cephalis (with the cortinar plate) often rests immediately upon the centre of the
tripod ; in the majority of NASSELLAEIA, however, this near relation is altered by reason
of later changes and secondary modifications.

The number of various forms, developed from these simple original structural elements
of the skeleton, is astonishing, and there are described more than three hundred genera and
nearly two thousand species of this legion in the following pages. This large number
may be easily increased by subsequent observers. Since in all these MONOPYLEA the
characteristic structure of the central capsule is identical, and also the structural
elements of the siliceous skeleton are similar, it is very probable that they may
have arisen from a single common stock. But it is very difficult (and at present
impossible) to explain a natural monophyletic system of this large legion. The greatest
difficulty is presented by the fact that the three structural elements mentioned
above, viz., the sagittal ring, the basal tripod, and the latticed cephalis, are not
constantly united, but each alone may also constitute the skeleton by itself. In this
respect the following seven cases are possible, and are actually realised.

A. The skeleton is composed of the sagittal ring only and of its spiny appendages,
without basal tripod and without latticed cephalis. This is the case in the majority of
Stephoidea (Stephanida, Semantida, Coronida, and Tympanida).

B.. The skeleton is composed of a basal tripod only (Plagiacantha), or of a tripod
in the centre of which arises a vertical apical horn (Plagoniscus), and often of an
irregular framework, arising from the rods of the tripod ; but there is neither a trace of
a sagittal ring nor a complete latticed cephalis. This is the case in the remarkable
suborder Plectoidea (Plagonida and Plectanida).

C. The skeleton is composed of a latticed cephalis only, a simple ovate or sub-
spherical fenestrated shell, which encloses the monopylean central capsule; there is no

REPORT ON THE RADIOLARIA. 893

trace of a sagittal ring nor of a basal tripod. This is the case in the remarkable family
of Cyrtocalpida (Archicorida and Archicapsida), in numerous Botryodea and in other
Cyrtellaria.

D. The skeleton is composed of a sagittal ring and a basal tripod, without latticed
cephalis. This is the case in a few, but very important forms of Stephoidea:
Cortina, Stephanium, Cortiniscus, Stephaniscus, Podocoronis, and some allied genera.

E. The skeleton is composed of a sagittal ring and a latticed cephalis, but without
basal tripod. This is the case in numerous Cyrtellaria, in the Circospyrida (or
Zygospyrida apoda: Dictyospyris, Circospyris) and some other Spyroidea; and in
a large number of Botryodea and Cyrtoidea eradiata (a part of the Sethocyrtida,
Theocyrtida, Lithocampida, and others).

F. The shell is composed of a basal tripod and a latticed cephalis, but without any
trace of the sagittal ring. This is the case in numerous Cyrtoidea triradiata and
multiradiata, and perhaps in the majority of the following families — Tripocalpida,
Tripocyrtida, Podocyrtida, and Podocampida.

G. The shell is composed of all three above-mentioned elements, of a sagittal ring, a
basal tripod, and a latticed cephalis. This is the case in the great majority of Spyroidea
(with a few exceptions only), and perhaps also in the majority of Cyrtoidea.

The survey of these seven groups, A to G, each of which is represented by
numerous living forms, shows clearly how difficult and complicated the morphology
and phylogeny of the numerous NASSELLARIA must be. For all possible combinations
of the three original structural elements are realised abundantly, and in such compli-
cated relations, and so intermingled in the different orders and families, that it seems
nearly hopeless to answer the question of their true origin. The identity in the
structure of the central capsule, however, in all these MONOPYLEA, makes it probable
that they have all arisen originally from the skeletonless Nassellida (Cystidium,
Nassella), either in a monophyletic or in a polyphyletic way. In this respect the
following phylogenetical hypotheses are possible.

1. Monophyletic hypothesis, deriving all NASSELLARIA from a simple sagittal ring
(Archicircus, Lithocircus, &c., PI. 81). The groups A, D, E, and G may be derived
easily from such a ring, but the groups B, C, and F only by means of the hypothesis
that the original ring may be completely reduced and finally lost. This hypothesis
was stated by me in the years 1877 to 1879, when I had got the first general survey of
the astonishing number of new NASSELLARIA in the Challenger collection, and as I had
found the sagittal ring in the majority of them. This, my former hypothesis, is mentioned
by Eichard Hertwig (1879, loc. cit., pp. 68, 126). It was afterwards supported with
particular energy by 0. Biitschli (1882, Zeitschr. fur wiss. Zool., Bd. XXXVI. ).

2. Monophyletic hypothesis, deriving all NASSELLARIA from a basal tripod
(Triplagia, Plagoniscus, &c., PI. 91). The groups B, D, F, and G, all triradiate, may

894 THE VOYAGE OF H.M.S. CHALLENGER.

be derived easily from such a tripod ; but the groups A, C, and E only by means of
the hypothesis that the original tripod may be completely reduced and finally lost.
This hypothesis was employed in 1881 in my Prodromus, since I had convinced myself
that the " triradial structure " is prevalent in the great majority of NASSELLARIA, and
is perhaps more important than the sagittal ring.

3. Monophyletic hypothesis, deriving all NASSELLARIA from a latticed cephalis,
a simple ovate or subspherical fenestrated shell without ring and tripod (Cyrtocalpis,
Archicapsa, &c.). The groups C, E, F, and G may be derived easily from such a cephalis,
but the groups A, B, and D only by means of the hypothesis that the sagittal ring as
well as the basal tripod may remain as the last remnants of a reduced cephalis. This
hypothesis was given in 1862 in my Monograph, where I constructed the first pedigree
of Eadiolaria (p. 234). I there derived all the Cyrtida from the Sphseroidea
(Cyrtidosphcera), supposing that Cyrtocalpis and some other Monocyrtida may form a
direct phylogenetical passage from the Sphseroidea to the Cyrtoidea.

4. Polyphyletic hypotheses, deriving the different groups of NASSELLARIA from
different skeletonless Nassellida, by development of simple siliceous skeletons in different
ways. Among the numerous polyphyletic hypotheses which are possible, one of the
simplest would be the supposition that three different fundamental forms of skeleton may
have arisen independently one from another : (l) a simple sagittal ring as original form
of the Stephoidea and Spyroidea (A) ; (2) a simple basal tripod as original form
of the Plectoidea (B) ; (3) a simple latticed cephalis as original form of the
Botryodea and Cyrtoidea (C). This triphyletic hypothesis is supported by R.
Hertwig (1879, loc. cit., p. 136); he assumes that the original skeletonless Nassellida
(Cystidium) have produced three different branches, his " Acanthodesmida "
(=Stephoidea and Spyroidea) with a primary ring, his " Plagiacanthida "
( = Plectoidea) with a primary tripod, and his Cyrtida (=Botryodea and
Cyrtoidea) with a primary cephalis. This hypothesis seems rather probable on the
first view ; but it meets with the greatest difficulties in view of the fact that these
three original elements of the skeleton are more or less evidently combined in the great'
majority of NASSELLARIA. The greatest difficulty arises from the fact that often among
very similar and closely allied forms the first exhibits all three elements (A, B, C) com-
bined, whilst the second has a combination of A and B, the third of B and C, the
fourth of A and C ; and there are other forms, very similar to the former, in which one
element only is recognisable. Another difficulty arises from the fact that the intimate
structure of the cephalis in the majority ofCyrtellariais not perfectly known, and
often exhibits structures which are difficult to explain with regard to the three elements
A, B, C. Under these circumstances further researches on the numerous imperfectly
known NASSELLARIA are required, and chiefly accurate observations on their more minute
structure and on their important ontogeny.

REPORT ON THE RADIOLARIA.

895

We divide the immense legion of NASSELLARIA into two large orders, the
Plectellaria without complete lattice-shell, and the Cyrtellaria with a
complete lattice-shell or a "cephalis," including the central capsule; the latter, of
course, have arisen from the former. The Plectellaria comprise three different
suborders, the Nassoidea (without skeleton), the Plectoidea (with a tripodal
skeleton, without ring), and the Stephoidea (with a primary sagittal ring, with or
without tripod). The Cyrtellaria again also comprise three different suborders, the
Spyroidea (with bilocular cephalis and a sagittal constriction), the Botryodea
(with multilocular and lobate cephalis, exhibiting two or more constrictions and three
or more lobes), and the Cyrtoidea (with simple, unilocular cephalis, without con-
striction).

Synopsis of the Orders and Suborders of NASSELLAKIA.

No skeleton, . . . .1. Nassoidea.

I. Order

PLECTELLARIA.

Nassellaria without complete lattice-shell.

II. Order

CYRTELLARIA.
Nassellaria with a complete lattice-shell.

Skeleton with a basal tripod, without

ring, . . . . .2. Plectoidea.

Skeleton with a sagittal ring (usually

without tripod), . . . 3. Stephoidea.

Cephalis bilocular, with a sagittal con-
striction, . . . .4. Spyroidea.

Cephalis multilocular, with two or more

constrictions and lobes, . . 5. Botryodea.

Cephalis simple, without constriction and
lobes, . . . . .6. Cyrtoidea.

Order V. PLECTELLARIA, Haeckel, 1883.

Definition, — NASSELLARIA without complete lattice-shell, usually with an incomplete
skeleton, formed of a ring, a tripod, or an irregular framework

Suborder I. NASSOIDEA, Haeckel.
Definition. — NASSELLARIA without skeleton. Single family Nassellida.

896 THE VOYAGE OF H.M.S. CHALLENGER.

Family XLV. NASSELLIDA, Haeckel.

Cystidina, Haeckel, 1883, Sitzungsb. Jena Ges. fur Naturw., Februar 16.

Definition. — NASSELLARIA without skeleton. The soft body composed of a
monopylean central capsule (with porochora and podoconus) and of a surrounding
jelly- veil or calymma.

The family Nassellida comprises the simplest and most primitive forms of
NASSELLARIA, the only group which is entirely without a skeleton. The central capsule
is therefore perfectly free and naked, enveloped by the calymma only, as in the
Colloidea among the SPUMELLARIA, in the Phseodinida among the PH^EODARIA.
Probably these naked and skeletonless MONOPYLEA must be regarded as surviving
remnants of the common ancestral group of this legion ; but the possibility is not
excluded that the few observed forms are either young NASSELLARIA which have not yet
secreted a skeleton, or older NASSELLARIA which have lost their original skeleton.

We distinguish in this small family two genera only : Cystidium with hyaline, not
foamy calymma, without extracapsular alveoles, and Nassella, with a very voluminous
foamy calymma, including numerous large alveoles ; the former corresponds to Actissa
and the latter to Thalassicolla among the Colloidea or the skeletonless SPUMELLARIA.
But in these two latter genera, as in all PERIPYLEA, the central capsule is perforated
everywhere by innumerable small pores ; the two former genera, however, exhibit the
same characteristic podoconus in the central capsule, and the same porochora at its
base, as all the other MONOPYLEA. The pseudopodia are protruded from the central
capsule through the porochora only.

TJie Central Capsule is in the two observed genera either ovate or nearly spherical,
usually slightly tapering towards the basal mouth. Its transverse section is constantly
circular. The membrane of the capsule is usually rather thick and double-contoured,
and bears on the truncate basal pole a circular " porochora " or area porosa, through
which the pseudopodia are protruded. The porochora is either quite simple, circular, or
in some species trilobed, with three equal circular lobes, each of which is surrounded by
a girdle of small granules. The £>odoconus, or " pseudopodial-cone," arising vertically
from the horizontal basal porochora, is half as long as the central capsule, or longer,
simply conical and finely striped longitudinally. The nucleus lies usually in the upper-
most part of the central capsule, above or behind the podoconus, and is either spherical
or ovate, sometimes kidney-shaped. It includes one or more nucleoli.

Synopsis of the Genera of Nassellida.

Calymma hyaline, without alveoles, ....... 382. Cystidium.

Calymma foamy, with numerous large alveoles, ..... 383. Nassella.

REPORT ON THE EADIOLARIA. 897

Genus 382. Cystidium,1 E. Hertwig, 1879, Organismus d. Eadiol., p. 87.
Definition. — N assellida with hyaline calymma, without extracapsular alveoles.

The genus Cystidium is the simplest and most primitive among all NASSELLARIA,
and may be regarded as the common ancestral form of this legion, for which it has
the same high importance as Actissa for the SPUMELLARIA. The central capsule is quite
simple, ovate or nearly spherical, and included in a voluminous hyaline calymma, which
contains no large alveoles. Cystidium differs from Actissa, its probable ancestral
form, in the possession of the " podoconus " and its basal " porochora," characteristic
of all NASSELLARIA or MONOPYLEA.

1. Cystidium princeps, n. sp. (PL 91, fig. 1).

Central capsule ovate, one and a third times as long as broad. Podoconus with simple
circular porochora, about half as long as the capsule, surrounded at its base by red granules of
pigment. Nucleus spherical. Three equal oil-globules in the endoplasm. No pigment in the
voluminous calymma, which includes numerous xanthellae.

Dimensions. — Length of the central capsule 01, breadth 0'075 ; nucleus 0'035.

Habitat. — Indian Ocean, Maldive Islands (Haeckel), surface.

2. Cystidium lecythium, n. sp.

Central capsule ovate, one and a half times as long as broad. Podoconus with simple circular
porochora, three-fourths as long as the capsule. Nucleus ellipsoidal. No oil-globules in the
endoplasm. No pigment and no xanthellae in the calymma.

Dimensions. — Length of the central capsule 0'12, breadth O08 ; nucleus 0'04

Habitat. — Central Pacific, Station 271, surface.

3. Cystidium inerme, E. Hertwig.

Cystidium inerme, R Hertwig, 1879, Organismus d. Radio!., p. 87, Taf. vii. figs. 1-16.

Central capsule subspherical, a little longer than broad. Podoconus about two-thirds as long as
the capsule, with trifid porochora, which is composed of three equal circular lobes. Nucleus
spherical. Numerous oil-globules in the endoplasm. The calymma includes numerous xanthellse
and brown pigment around the mouth.

Dimensions. — Length of the central capsule 0'06, breadth 0'05 ; nucleus 0'03.

Habitat. — Mediterranean, Messina (R Hertwig), surface.

1 Cystidium= Small vesicle ; xvirrKiov.

(ZOOL. CHALL. EXP. — PART XL. — 1885.) Rr 113

898 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 383. Nassella,1 nov. gen.

Definition. — N assellida with foamy calymma, containing numerous large
extracapsular alveoles.

The genus Nassella differs from the preceding Cystidium, its probable ancestral
form, in the development of numerous large alveoles in the extracapsular calymma, and
therefore exhibits the same relation to it that Thalassicolla bears to Actissa among the
SPUMELLARIA. The foamy calymma is very voluminous, and includes numerous
symbiotic xanthellae.

1. Nassella thalassicolla, n. sp.

Central capsule spherical. Podoconus with simple circular porochora, half as long as the
capsule. Nucleus spherical. Numerous oil-globules in the endoplasm. Calymma spherical,
without pigment, with numerous xanthellse and large alveoles.

Dimensions. — Diameter of the central capsule 012, nucleus 0'04, calymma 0-6.

Habitat. — South Pacific, Station 300 (off Juan Fernandez), surface.

2. Nassella nassiterna, n. sp.

Central capsule ovate. Podoconus two-thirds as long as the capsule, trifid, with three equal
circular lobes (as in Cystidium inerme). Nucleus ovate. Three equal large oil-globules in the
endoplasm, corresponding to the three lobes of the porochora. Calymma ovate, in the upper half
much more voluminous than in the lower, including numerous large alveoli and xanthellse, and
around the mouth masses of black pigment.

Dimensions. — Diameter of the central capsule O'l, nucleus 0'03, calymma 0'8.

Habitat. — Indian Ocean, Madagascar (Rabbe), surface.

Suborder II. PLECTOIDEA, Haeckel.

Plectoidea vel Plectida, Haeckel, 1881, Prodromus, p. 423.

Plagiacanthida (sensu ampliori), R. Hertwig, 1879, Organismus d. Radiol., p. 72.

Definition. — NASSELLARIA with a rudimentary, originally tripodal skeleton, composed
of radial spines, arising from one common central point or central rod ; the spines are
simple or branched, and the branches may form by concrescence of their meeting ends a
loose wickerwork, but never a complete lattice-shell. Never a ring in the skeleton.

1 Nassella — Small wicker cage for fishing.

REPORT ON THE RADIOLARIA. 899

The suborder Plectoidea, hitherto known by few species only of "Plagiacanthida,"
comprises a large number of interesting NASSELLARIA, which belong partly to the simplest
and most primitive forms of this legion. It may be divided into two different families,
Plagonida and Plectanida. In the first family, Plagonida, the monopylean central
capsule is supported by a simple or rudimentary skeleton, composed only of a variable
number of radial spines united in a common centre. In the second family,' Plectanida,
the branches of these radial spines become united and form a loose irregular framework
with wide meshes, partly enclosing the central capsule, but never a perfect lattice-shell.

The Plectoidea differ from the following suborder, the Stephoidea, in the
absence of the ring, characteristic of the latter. Some slight traces, however,
indicate a near affinity between the ringless Plectoidea and the ring-bearing
Stephoidea. Both these suborders of Plectellaria differ from the closely
allied Cyrtellaria (Spyroidea, Botryodea, and Cyrtoidea) in the
absence of a complete lattice-shell. The morphological relation and phylogenetic
affinity between the former and the latter have already been discussed in the preceding
description of the legion NASSELLARIA (compare pp. 891—894).

The first known species of Plectoidea was observed in the North Atlantic
(on the Norwegian shore) in 1855 by my late friend Edouard Claparede, and described
and figured in his Etudes, &.c. (1858), under the name Plagiacantha arachnoides. He
considered it as a new genus of Acanthometrina. Another species, from the
Mediterranean, was described in the same year by Johannes Muller as Acanthodesmia
dumetum (1858, loc. cit., Taf. i. fig. 3). A third species, also Mediterranean, was
figured by me in 1865 under the name Acanthodesmia polybrocha. Finally, Eichard
Hertwig, 1879, in his Organismus der Eadiolarien, gave a very accurate description
of another Mediterranean form, Plagiacantha abietina (loc. cit., Taf. vii. fig. 6). He
first recognised the true character of MONOPYLEA in their monaxonian central
capsule, and observed at the same time the first NASSELLARITTM without skeleton, called
by him Cyrtidium inerme (loc. cit., Taf. vii. fig. 1). To these four known species,
representing three different genera, the rich collection of the Challenger has added so
many new forms that we may distinguish here not less than seventeen genera and
sixty-one species. In my Prodromus (1881, p. 423) I arranged these in two subfamilies,
the Plagonida and Plectanida, constituting together the family Plectida (identical with
the " Plagiacanthida " of Hertwig and Blitschli). But at present, regarding the
important relations of these Plectida to the other NASSELLARIA, it seems more con-
venient to give to them the rank of an independent suborder of Radiolaria, under the
name Plectoidea.

The peculiar structure of the central capsule of the Plectoidea, first recognised
by Richard Hertwig, allows no doubt of their being true MONOPYLEA or NASSELLARIA ;
and also their siliceous, originally triradiate skeleton indicates the nearest affinity to

900 THE VOYAGE OF H.M.S. CHALLENGER.

the other families of this legion. But a very difficult and as yet unsolved problem is
the important question, in what manner these different groups of NASSELLARIA are
phylogenetically connected. Either the Plectoide a — as the simplest of all — are
the original common ancestral group of this whole legion (as I assumed in my
Prodromus, 1881), or they are derived from the Stephoidea (by reduction of the
sagittal ring), or they have originated independently from them (if we suppose a poly-
phyletic origin of the MONOPYLEA. Compare above, p. 893, &c.). In any case the
typical " triradial structure " of the Plectoide a, prevalent also in the other groups of
this legion, is a very important and interesting fact.

The triradial skeleton of the Plectoidea exhibits in the two families of
Plagonida and Plectanida a complete homology of development, so that each genus of
the latter may be derived from a corresponding genus of the former, simply arisen by
concrescence or union of the branches of the radial spines. Therefore the only difference
between the two closely allied families is, that the branches of the radial spines in the
Plagonida remain free, whilst in the Plectanida they produce a loose framework or
wickerwork by union of their meeting ends. We express this complete homology in
the nomenclature of the Plectoidea, in each genus of Plagonida retaining the
syllable "Plag-" ; in each genus of Plectanida, correspondingly, the syllable "Plect-."

The number of radial spines composing the skeleton is originally three, and in all
not triradial genera is probably derived from three. For better survey we may divide
each family, according to the different number of rays, into four different subfamilies :
A, with three radial spines (Triplagida and Triplectida) ; B, with four radial spines
(Tetraplagida and Tetraplectida) ; C, with six radial spines (Hexaplagida and
Hexaplectida) ; and D, with numerous (seven to nine or more) radial spines (Polyplagida
and Polyplectida). The last three subfamilies have arisen probably from the first
triradial subfamily, by a secondary increase in the number of rays.

The important signification of the triradial structure, recurring in the most different
groups of NASSELLARIA, has been already pointed out sufficiently by myself and by
R Hertwig. But the triradial Plectoidea offer also another interesting relation of
this characteristic structure, some simple forms of this order appearing nearly identical
with the isolated triradial spicula of certain Beloidea (Thalassosphserida and
Sphserozoida). Even some more complex quadriradial and sexradial forms of the
latter reappear in exactly the same shape also in the former. This identity may be
perhaps an important indication of true affinity (compare below).

The simplest and probably the most original kind of triradial structure is exhibited
by the genera Triplagia and Triplecta (PI. 91, figs. 2, 7). Here three equal radial
spines lie in one horizontal plane and are united in a common central point at equal
angles, so that three lines connecting their distal ends form a regular equilateral
triangle. Simple triradial spicula of the same regular form are also found in many

REPORT ON THE RADIOLARIA. 901

Beloidea (Lainpoxanthium, Sphcerozoum, &c., Pis. 2 and 4). The central capsule
of these simplest Plectoidea (with vertical main axis) rests perpendicularly on the
horizontal triangle, formed by the triradial skeleton ; the porochora of the former (or
the " area porosa ") rests upon the central point of the latter.

Another kind of triradial structure characterises the genera Plagiacaniha and
Plectophora. The three radial spines united in the central point lie here not in one
plane, but diverge in different planes, so that they correspond to the three lateral
edges of a three-sided pyramid. Commonly the three spines are of equal size, and also
the angles between them equal, so that the pyramid is regular, sometimes very
flat, at other times more elevated. Spicula of exactly the same form are also found in
some Beloidea. Probably the three divergent spines are homologous to the three
basal feet of numerous Spyroidea and Cyrtoidea. The central capsule, accord-
ing to Hertwig, is placed in the apical part of the pyramid, the axes of both being
identical, and the porochora resting in the apex itself. This fact seems to contradict
the above-mentioned affinity ; but since in Tnplecta and Triplagia the three spines lie
horizontally, they may have changed this original position in different direction, in
Plagiacantha and Plectophora becoming divergent upwards, whereas in Plagoniscus
and Plectaniscus (as in the Spyroidea and Cyrtoidea) directed downwards.

The triradial structure, common to the Triplagida and Triplectida, is replaced by the
quadriradial structure in the Tetraplagida and Tetraplectida. Probably the latter have
been derived from the former by development of a fourth spine, and then this latter would
correspond to the "apical horn" of the other NASSELLARIA. But possibly also both struc-
tures have originated independently from one another. We may distinguish not less
than four different kinds of the quadriradial structure. In the first case all four spines
are equal, and diverge from a common central point at equal angles in different direc-
tions, corresponding to the four axes of a regular tetrahedron (Tetraplagia and
Tetraplecta, PL 91, figs. 3, 8).

In the second case all four spines are also equal, but they are not united in a
common central point, but opposite in pairs on the two poles of a common central rod
(Plagonidium). Therefore the skeleton possesses here the same form as in the
" geminate-biradiate " spicula of many Beloidea (e.g., Thalassoxanthium bifurcum
and Spheerozoum furcatuni). The development of the short horizontal middle rod, con-
necting the two divergent pairs of spines, is here probably effected by the porochora of
the central capsule resting upon it.

Whilst in these two cases of quadriradial structure all four spines are equal, in* two
other cases they become differentiated in a very remarkable manner. One spine is
vertically directed upwards, in shape and size different from the three others, which are
directed downwards ; the former corresponding probably to the " apical horn," the latter
to the three "basal feet," which are found in the great majority of the Spyroidea

902 THE VOYAGE OF H.M.S. CHALLENGER.

and Cyrtoidea. Therefore we encounter here for the first time that characteristic
" cortinar structure " which is complete in Cortina and Cortiniscus (PI. 92,
figs. 11—13, 21), and which may be regarded as the strongest argument for a close
relationship, or even for a common monophyletic origin of all NASSELLARIA.

The four spines, which we regard therefore as " cortinar spines," exhibit a twofold
kind of central junction. In the simpler case they are united in a common central
point, on which rests the porochora of the central capsule (Plagoniscus and Plectaniscus,
PL 91, figs. 4, 9). These forms are nearer to Cortina, and may be derived immedi-
ately from Tetraplagia and Tetraplecta by differentiation of the four equal spines. In
the other case the four cortinar spines are separated in pairs, diverging from the two
poles of a short horizontal common " central rod " (Plagiocarpa and Periplecta,
PI. 91, figs. 5, 10). These forms may be compared with the spicula of some
Beloidea and derived from Plagonidium ; but their basal central rod may be
compared again with the basal part of the sagittal ring of Cortina, and this comparison
becomes. very important in those forms like Plagiocarpa procortina (PI. 91, fig. 5).
Here the four spines approach very nearly to those of Cortina; the two ventral spines
(or pectoral feet) on the anterior pole of the middle rod are equal, but very different
from the two dorsal spines, arising from the posterior pole ; the lower odd spine of the
latter corresponds to the " caudal foot," the upper spine to the " apical horn " of
Cortina and of the Cyrtellaria. The vertical plane, determined by these two
dorsal spines, is the sagittal plane, and two opposite curved branches which lie in this
plane (an upper arising from the basal part of the apical spine and a lower arising from
the anterior pole of the middle rod) may be regarded as ventral parts of an incomplete
sagittal ring. This interesting form and some other similar Tetraplagida may be
regarded either as beginning Stephoidea (Cortina, with incomplete sagittal ring)
or as retrograde Stephoidea (Cortina, with partly reduced sagittal ring). In every
case they seem to indicate the near relationship between the Stephoidea and
Plectoidea.

Another argument for this close relationship may be found in the position of the
central capsule in the interesting genus Plagiocarpa (PI. 91, fig. 5). Its basal part
(with the porochora) rests upon the common central rod, its ventral face upon the ventral
prolongation of the latter, its dorsal face upon the apical horn ; its axis lies in the
sagittal plane. The three basal spines (the odd caudal and the paired pectoral feet)
diverge from its basal pole downwards in the same manner as in the Cortinida, the
Zygospyrida and the Monocyrtida.

Less important than those quadriradial Tetraplagida and Tetraplectida, are the
sexradial Plectoidea, the Hexaplagida and Hexaplectida. These may be derived
immediately from the triradial Plectoidea by prolongation of the three primary
original spines (of Plagiacantha) over the common central point. Here also two

REPORT ON THE RADIOLARIA. 903

different kinds of central junction are found. In the simpler case all six radial spines
arise from a common central point (Hexaplagia and Hexaplecta). In the other case
the six radial spines arise from the two poles of a short horizontal common central rod,
opposed in two groups, each of three spines (Plagonium and Plectanium, PL 91, figs.
6, 11). In this latter case the single corresponding spines of the two opposite groups
are usually parallel, and exhibit therefore exactly the same characteristic " geminate-
triradiate " form which is found in many Beloidea (e.g., in the common Sphcerozoum
punctatum and the similar Lampoxanthium punctatum).

The fourth and last group of this suborder contains the multiradiate Plectoidea, the
Polyplagida and Polyplectida. Here the number of radial spines, diverging from the
common centre, exceeds six, and is commonly seven to nine, at other times ten to twelve
or more (Polyplagia and Polyplecta, PL 91, fig. 12). When these two genera are
better known from further accurate observations, they may probably be divided into
several different genera (as already proposed in my Prodromus, 1881), since not only
the number, but also the central junction and the arrangement of the numerous radial
spines in the few observed species seems to be very different. In some seven-radiate
species (e.g., Polyplecta heptacantha) four larger spines seem to be true " cortinar
spines," the three smaller secondary productions of the former. In the nine-radiate
species the nine spines seem to be sometimes basal branches of three primary spines,
at other times six secondary intercalated between the three primary (like Enneaphormis,
PL 57, fig. 9). In those multiradial Plectoidea, in which the number of spines
amounts to ten or twelve or more, the laws of disposition are not yet recognised.

Comparing these different productions of the skeleton in the numerous Plectoidea,
we find expressed two remarkable and very different affinities. On the one hand many
Plectoidea exhibit exactly the same peculiar forms, which are only found besides
in the Beloidea (as many species of Triplagia, Plagiacantha, Tetraplagia,
Plagonidium, Hexaplagia, and Plagonium). On the other hand many Plectoidea
bear the same characteristic composition of the skeleton (or the " cortinar structure ")
which is found in the Cortinida among the Stephoidea, and in numerous
Spyroidea and Cyrtoidea, which all agree in the possession of three divergent
basal feet and a vertical apical horn. A most important argument for the close affinity
of all these " cortinar NASSELLAKIA " seems to be given by the fact that the sagittal
ring, which in Cortina is combined with the quadriradial structure, exhibits in the
Cyrtellaria the most different stages of development; in one group it is complete,
in the second incomplete, and in the third it has completely disappeared.

The form of the radial spines composing the skeleton is usually three-sided
prismatic, gradually tapering from the thicker central base towards the distal apex ;
sometimes they are slender pyramidal. More rarely the spines are cylindrical or slender
conical. In the majority of species the spines are straight, in the minority more or

904 THE VOYAGE OF H.M.S. CHALLENGER.

less curved. In very few species only are they quite simple, without branches.
They are nearly always more or less branched, in many larger species very richly
ramified. The modes of ramification are rather variable. In the majority of
Plectoidea the spines are rather regularly verticillate, bearing an increasing number
of verticils, each of which is composed of three divergent branches. These arise from
the three edges of the spine, and all the branches of one edge are usually parallel, either
perpendicular to the spine, or directed at an acute angle towards its apex. When the
verticils are numerous (five to ten or more), their size commonly tapers gradually towards
the apex. Pinnate spines occur more rarely than verticillate ones ; in this case the two
paired lateral edges only of the prismatic spine bear opposite or alternate branches,
whilst the odd middle edge bears no ramules. In some species the spines are singly
or doubly forked. In many species (mainly those with cylindrical spines) the ramifica-
tion of the spines is more or less irregular.

Whilst in all Plagonida the branches of the spines remain perfectly free, in all
Plectanida, again, the meeting ends of the branches become united and grow together,
and by this concrescence a loose network arises, like wickerwork, which partly encloses the
central capsule and the central parts of the spines, on which it rests. The meshes of
this loose wickerwork are large, either quite irregular, of very different size and form, or
more or less regular, with a certain form and arrangement of the meshes, effected by
the peculiar kind of ramification. Commonly the siliceous threads of the arachnoidal
wickerwork are very thin, often extremely delicate, representing " pseudopodia
metamorphosed into silex." Sometimes the wickerwork is spongy. Its surface is
constantly rough and bristly, with free ends of the spine -branches, never covered with
a regular lattice-plate, as in the Cyrtellaria (Spyroidea, Botryodea> and
Cyrtoidea).

The entire form of the central wickerwork is in the minority of Plectanida quite
irregular and indefinite ; in the majority, however, a certain more or less regular entire
form is recognisable, effected by a certain, more or less regular origin and mode of
the connection of the meeting branches. So in some species of Triplecta (PI. 91,
fig. 7) the network represents a triangular plate, of Plectophora and Plectaniscus a
three-sided pyramid, of Tetraplecta (PI. 91, fig. 3) a tetrahedron, and in many other
species a polyhedron of more or less regular form. Some species of Plectanida become
very similar to certain species of Stephoidea, Spyroidea, and Cyrtoidea;
so Plectaniscus and Periplecta approach to Cortina and Cortiniscus, Pteroscenium
and Olathrocorys, &c. (compare Pis. 92, 93, 53, 64, &c.). They may represent a
true phylogenetic connection between both groups. But in these cases also the
distinction is determined by the fact that the true Plectoidea never possess a
complete sagittal ring (like the Stephoidea) nor a regular lattice-shell (like the
Spyroidea, Botryodea, and Cyrtoidea).

REPORT ON THE RADIOLARIA. 905

The Central Capsule of the Plectoidea constantly exhibits the peculiar
characters of the MONOPYLEA or NASSELLARIA. It is commonly ovate, more rarely
ellipsoidal or even spherical, sometimes conical or lentelliptical. The lower or basal
pole of its vertical main axis constantly exhibits the characteristic " porochora " (or the
area porosa) of the MONOPYLEA, and upon this rests the peculiar " podoconus " (or the
pseudopodial-cone) of this legion. On this porochora the central capsule is in
immediate connection with the central point of the skeleton, or the horizontal common
central rod, from which the radial spines arise. The endoplasm, or the protoplasm of
the central capsule (besides the podoconus), contains commonly one large alveole or
several small vacuoles, and often pigment-granules. The nucleus is large, spherical or
ovate, and exhibits the same character as in all the other MONOPYLEA ; it encloses
usually a single nucleolus.

The position of the central capsule and its topographical relation to the skeleton
offers in the different Plectoidea some important and as yet unsolved problems,
which can be answered only by fresh and accurate observations on living specimens. In
Triplagia, and Triplecta, where the triangular skeleton lies in a horizontal plane,
the vertical main axis of the central capsule is perpendicular to the central point of that
supporting triangle. In Plagiacantha and Plectophora, where the three radial spines
correspond to the edges of a flat pyramid, the capsule is enclosed in the pyramidal
space of the latter, its basal pole touching the apex ; therefore in the normal position of
the body the three divergent rays are directed upwards. In Tetraplagia and
Tetraplecta probably the same position is retained, and therefore the fourth free
spine, here developed, is probably directed vertically downwards. In Plagoniscus and
Plectaniscus, however, and, moreover, in the closely allied Plagiocarpa and the corres-
ponding Periplecta (PI. 91, figs. 5, 10) the position of the central capsule, relative to
the skeleton, seems to be inverse, and to agree with that of the Stephoidea
(Cortina, Cortiniscus, &c.) and the Cyrtoidea (Pteroscenium, Clathrocorys, &c.);
the three divergent spines are here directed downwards (as basal feet), whilst the
opposite fourth spine is vertically directed upwards (as an apical horn); the capsule
rests here upon the tripod, which lies below it, and is inclined with its dorsal face to the
apical spine. In the majority of the other Plectoidea the position of the central
capsule and its relation to the skeleton are not yet sufficiently observed, and require
further accurate researches. Its position seems to be very different in the several genera.
The capsule is never perforated by parts of the skeleton; this latter is constantly
extra-capsular.

The physiological value of the skeleton, with regard to the central capsule, is
different in the Plagonida and Plectanida; in the former it supports, in the latter it
encloses the capsule like a shell. In the Nassellida, where no skeleton is developed, the
central capsule is quite free and naked, enveloped only by the calymma.

(ZOOL. CHALL. EXP. PART XL. 1885.) Rr 114

906 THE VOYAGE OF H.M.S. CHALLENGER.

The calymma or the extracapsular jelly -veil in all Plectoidea is ' voluminous,
and encloses not only the central capsule completely, but also the skeleton wholly or
partially. Its form is of the greatest value for the development and configuration
of the skeleton. Sometimes the calymma is alveolate and foamy, as in Nassella and
the common Thalassicolla. In several other Plectoidea the calymma seems to
include numerous small vacuoles, sometimes also pigment-granules. Xanthellse are
commonly scattered in it in great numbers. The pseudopodia, arising in a large bunch
from the porochora of the capsule, and running along the branches of the radial spines,
seem to be always numerous, richly branched, and with a strong tendency to form
anastomoses. The peculiar form of their network is often exactly preserved in the con-
formation of the skeleton, produced by them. The peculiarities of this network require
further accurate observations, as does the whole organisation of the Plectoidea.

Synopsis of the Families of Plectoidea.

I. Skeleton (originally tripodal) composed of radial spines united in a common

centre and supporting the central capsule, without wicker-work, . .1. PLAGONIDA,

II. Skeleton (originally tripodal) wattled, with irregular wicker-work, composed of the

united branches of radial spines and enveloping the central capsule, . . 2. PLECTANIDA.

Family XL VI. PLAGONIDA, Haeckel.

Plagonida, Haeckel, 1881, Prodromus, p. 423.

Plagiacanthida (sensu strictiori), Eichard Hertwig, 1879, Organismus d. Eadiol., p. 72.

Definition. — P lectoidea with a spiny skeleton, composed of radial spines, which
arise from a common central point or central rod, and support the free central capsule.

The family Plagonida comprises those NASSELLARIA in which the skeleton is
only composed of united radial spines, arising from a common centre, without any connec-
tion of meeting branches of the spines ; the rudimentary skeleton exhibits therefore
neither a loose wickerwork (as in the closely allied Plectanida), nor a ring (as in the
Stephoidea), nor a complete lattice-shell (as in the Cyrtellaria, the
Spyroidea, Botryodea, and Cyrtoidea). The central capsule, which
possesses all the characters of the MONOPYLEA, is therefore free, not enclosed, and
only on one side supported or partly protected by the radial spines or their branches.

Two species only of Plagonida have been hitherto known. The first form described is
the Plagiacantha arachnoides, discovered thirty years ago (1855) by Claparede on the
western shore of Norway. Another species of the same genus, from the Mediterranean,
was very accurately described by Eichard Hertwig in 1879 in his Organismus der

REPORT ON THE RADIOLARIA. 907

Eadiolarien (Plagiacantha abietina). Upon these two species the latter founded his
family Plagiacanthida, a term which was afterwards employed by Biitschli and others,
for the whole group of Plectoidea. Many new forms are contained in the collec-
tion of the Challenger, so that we may describe here nine genera and thirty-four
species.

The family Plagonida may be divided into four different subfamilies, according to
the numbers of the radial spines which compose the skeleton : Triplagida with three,
Tetraplagida with four, Hexaplagida with six, and Polyplagida with numerous (seven to
nine or more) radial spines. These are united commonly in one common central point,
upon which rests the basal pole of the central capsule, with the porochora. More rarely
(in the genera Plagonidium, Plagiocarpa, and Plagonium) the spines arise in two
opposite groups (each with two or three spines) from the two poles of a common central
rod; in this case the basal pole of the central capsule with the porochora rests upon
the horizontal common rod, which corresponds probably to the basal part of the sagittal
ring of the Stephoidea and Cyrtellaria.

The different forms which the skeleton of the Plagonida assumes in the different
genera of this family, and the important relations which these exhibit on the one hand to
the spicula of the Beloidea, and on the other hand to the shell of some Stephoidea
(Cortina, Cortiniscus, &c.) and Cyrtoidea (Pteroscenium, Clathrocorys, &c.), have
been already pointed out in the preceding description of the suborder Plectoidea.
There it is also demonstrated, that all these different forms may be derived from the
simplest triradial forms, Triplagia and Plagiacantha (compare above, pp. 900-904).

Whilst the genera of the Plagonida are characterised by the number of the radial
spines and the peculiar mode of junction in a common central point or at the two poles of a
common central rod, the different species of this family may be defined by the peculiar form
of the spines and their branches. These morphological characters have also been already
described above. We repeat here only that the radial spines in the majority of species
are three-sided prismatic and verticillate, each verticil commonly with three branches.
The distal ends of these branches remain constantly free, and are never united, as is
always the case in the following family.

The Central Capsule of the Plagonida exhibits the general characters of all
MONOPYLEA (compare above, p. 890). It is commonly ovate or ellipsoidal, with vertical
main axis ; on the lower pole of the latter is the porochora (or the " area porosa," from
which all pseudopodia radiate). This is in immediate connection with the central point
or central rod of the skeleton, in which its radial spines are united. The topographical
relation of the supporting skeleton to the central capsule seems to exhibit in the
different genera of the Plagonida remarkable differences, as already demonstrated above
(p. 905).

908

THE VOYAGE OF H.M.S. CHALLENGER.

I. Subfamily

Triplagida.
Three radial spines.

II. Subfamily

Tetraplagida.
Four radial spines.

III. Subfamily

Hexaplagida.
Six radial spines.

IV. Subfamily

Polyplagida.
Numerous radial spines.

Synopsis of the Genera of Plagonida.

Three spines lying in one horizontal plane, .

Three spines corresponding to the edges of a flat pyramid,

{All four spines equal,
One apical spine opposed to
three basal spines,

Four spines arising in two f A11 four 8Pines e1ual>
pairs from the poles of a -< „

common central rod. 1 Ont? aP'f l ^Plne °PP°sed to

[ three basal spines,

Six spines arising from one common central point, .

Six spines arising in two opposite groups from the poles of a
common central rod, .....

Numerous (seven to nine or more) radial spines arising from
a common centre (either a central point or a branched
rod), .

384. Triplagia.

385. Plagiacantha.

386. Tetraplagia.

387. Plagoniscus.

388. Plagonidium.

389. Plagiocarpa.

390. Hexaplagia.

391. Plagonium.

392. Polyplagia.

Subfamily 1. TRIPLAGIDA, Haeckel, 1881, Prodromus, p. 423.
Definition. — P lagonida with three radial spines.

Genus 384. Triplagia,1 Haeckel, 1881, Prodromus, p. 423.

Definition. — Plagonida with three radial spines, arising from one common
central point and lying in one horizontal plane.

The genus Triplagia and the following closely allied Plagiacantha may be
regarded as the simplest and most primitive forms of the Plectoidea, perhaps as
the common ancestral stock of this suborder. The skeleton is composed of three simple
or branched radial spines, arising from one common central point. These three spines
in Triplagia lie in one and the same plane, whilst in Plagiacantha they lie in different
planes. Therefore the former exhibits the simplest type of the triradial structure,
common to the majority of NASSELLARIA.

1 Triplagia= Triangular or three-radial ;

REPORT ON THE RADIOLARIA. 909

1. Triplagia primordialitt, n. sp. (PL 91, fig. 2).

Spines straight, of equal size and similar form, equidistant, three-sided prismatic, each with two
pairs of opposite lateral branches, which are correspondingly parallel to the two other spines ; the
proximal branches twice as long as the distal branches.

Dimensions. — Length of each spine O2, of the basal branches 0'07.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Triplagia triradialis, n. sp.

Spines straight, of equal size and similar form, equidistant, three-sided prismatic, regularly pin-
nate, with six pairs of opposite pinnulse, tapering gradually towards the distal ends ; the basal
pinnulse are again branched, with straight ramules.

Dimensions. — Length of each spine 0'27, of the basal branches 0'08.

Habitat. — North Pacific, Station 256, surface.

3. Triplagia horizontalis, n. sp.

Spines curved, cylindrical, irregularly branched, with- three primary and nine to twelve
secondary branches, which are also slightly curved. The angles between the bases of the three
spines are equal, but the size and form of the branches different.

Dimensions. — Length of the three spines 0'15 to 0'25, of the basal branches 0'05 to 0'08.

Habitat. — West Tropical Pacific, Station 225, depth 4475 fathoms.

Genus 385. Plagiacantha,1 Claparede, 1856, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, November 13.

Definition. — Plagonida with three radial spines, arising from one common
central point and corresponding to the edges of a three-sided pyramid.

The genus Plagiacantha agrees with the preceding Triplagia in the simple
structure of the triradial skeleton, composed of three diverging radial spines, which are
united in a common centre at the oral pole of the central capsule. But whilst the
three radial rods of Triplagia lie in one horizontal plane, here they lie in different
planes and correspond to the three edges of a flat pyramid. Plagiacantha
arachnoides, described in 1856 by Claparede, was the earliest known form of all
Plectoidea.

1 Plagiacantha = Having spines on the sides ; ***y/of, «x«»9a-

910 THE VOYAGE OF H.M.S. CHALLENGES.

1. Plagiacantha arachnoides, Claparfede.

Plagiacantha arachnoides, Claparede, 1856, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

November 13.
Plagiacantha arachnoides, Claparede, 1858, Etudes sur les Infusoires et les Rhizopodes, p. 462

(pL xxii. fig. 8).
Acanthometra arachnoides, Claparede, 1855, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 675.

Spines straight, cylindrical, divided into three divergent straight branches of equal size ; each
branch two to three times as. long as the simple thicker basal part.

Dimensions. — Length of the spines 012 to 0'2, of the branches O08 to 014.
Habitat. — North Atlantic, coast of Norway, Claparede, surface.

2. Plagiacantha furcata, n. sp.

Spines straight, cylindrical, divided into two divergent straight branches of equal size, of about
the same length as the simple basal part. The spines and their branches are smooth.
Dimensions. — Length of the spines 0'24, of their fork-branches 012.
Habitat. — North Pacific, Station 254, surface.

3. Plagiacantha dodecantha, n. sp.

Spines straight, three-sided prismatic, in the middle with one verticil composed of three
divergent straight branches of equal size, of about the same length as the simple basal part. The
edges of the spines and their branches are thorny.

Dimensions. — Length of the spines 0'24, of the branches 01.

Habitat. — Central Pacific, Station 274, surface.

4. Plagiacantha abietina, Richard Hertwig.

Plagiacantha abietina, Richard Hertwig, 1879, Organjsmus d. Radiol., p. 72, Taf. vii.
figs. 6-6J.

Spines straight, three-sided prismatic, with three verticils of three divergent straight lateral
branches, decreasing in size towards the distal end ; the branches of the first verticil about twice as
long as those of the second, and four times as long as those of the third verticil. All nine branches
of each spine simple, straight, three-sided pyramidal.

Dimensions. — Length of the spines 0'2 to 0'3, of the basal branches O'OG to 0'08.

Habitat. — Mediterranean, Messina (R Hertwig), surface.

5. Plagiacantha verticillata, n. sp.

Spines curved, three-sided prismatic, with six to nine verticils of three divergent branches,
decreasing in size towards the distal end ; the branches of the first verticil about twice as long as
those of the fourth verticil. All branches simple, slightly curved, bristle-shaped.

Dimensions. — Length of the spines 0'27, of the basal branches 012.

Habitat. — South Pacific, Station 296, surface.

REPORT ON THE RADIOLARIA. 911

i

6. Plagiacantha elatine, n. sp.

Spines straight, three-sided prismatic, with prominent wing-like edges and ten to twelve verticils
of three divergent branches, decreasing in size towards the distal end ; the branches of the three or
four basal verticils are again ramified and much larger than the simple branches of the distal
verticils.

Dimensions. — Length of the spines O36, of the basal branches 014.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Subfamily 2. TETRAPLAGIDA, Haeckel, 1881, Prodromus, p. 424.
Definition. — P lagonida with four radial spines.

Genus 386. Tetraplagia,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — P lagonida with four equal radial spines, arising from one common
central point, and corresponding to the four axes of a tetrahedron.

The genus Tetraplagia is one of the most important Plectoidea, and possibly
the common ancestral form of many NASSELLAEIA (compare above, p. 901). The
skeleton is composed of four radial rods, diverging from one common centre in different
directions, and corresponding to the four axes, which extend from the central point of a
tetrahedron to the central points of its four faces. The whole skeleton of Tetraplagia
exhibits therefore the same form, which is observed in the single quadriradiate spicula
of some Beloidea (in some species of Lampoxanthium, Spharozoum, &c.).

1. Tetraplagia geometrica, n. sp.

Spines straight, cylindrical, perfectly equal, corresponding in regular disposition exactly to the
four geometrical axes of a regular tetrahedron ; in the middle arise from each spine two opposite
equal lateral branches of half the length of the spine.

Dimensions. — Length of the spines 012, of the branches 0'06.

Habitat. — Central Pacific, Station 266, surface.

2. Tetraplagia phcenaxonia, n. sp. (PL 91, fig. 3).

Spines straight or slightly curved, three-sided prismatic, with irregular short branches arising
from the three edges ; the branches are thorny, tapering towards the apex.
Dimensions. — Length of the spines 015, of the basal branches 0'03.
Habitat. — Tropical Atlantic, Station 332, surface.

1 Tetraplagia = Four-sided ; re-rj cnrA«y/oj.

912 THE VOYAGE OF H.M.S. CHALLENGER.

3. Tetraplagia dbietina, Haeckel.

Plagiacantha dbietina, var. quadrispina, Kichard Hertwig, 1879, Organismus d. Eadiol., p. 73.

Spines straight, three-sided prismatic, verticillate, with six to eight verticils of three simple
straight branches ; the branches of each edge are parallel, tapering towards the distal end.
R Hertwig regards this species only as a four-spined variety of his three-spined Plagiacantha
abietina ; but a specimen, observed by me in Corfu, exhibited all the characters of Tetraplagia.

Dimensions. — Length of the spines 0'2, of the basal branches 0'07.

Habitat. — Mediterranean (Messina, Corfu), surface.

Genus 387. Plagoniscus,1 n. gen.

Definition. — P lagonida with four unequal radial spines, arising from one
common central point ; one vertical or apical spine opposed to three divergent or basal
spines.

The genus Plagoniscus agrees with the preceding Tetraplagia (its probable
ancestral form) in the possession of four radial spines, diverging from one common
central point. But whilst in this latter all four spines are equal, corresponding
exactly to the four axes of a tetrahedron, here in Playiocarpa an important .difference
exists between one vertical or apical spine and three other divergent basal spines ;
these latter corresponding probably to the three " feet," the former to the single " apical
horn " of the majority of NASSELLARIA. Perhaps we find here one of the oldest
and simplest types of their " triradial or cortinar structure " (compare above, p. 902).

1. Plagoniscus tripodiscus, n. sp. (PL 91, fig. 4).

Spines three-sided prismatic, thorny. Apical spine nearly straight, verticillate, with four to
five verticils of three thorny branches, tapering towards the apex. Three basal spines somewhat
shorter, curved, with three thorny edges.

Dimensions. — Length of the apical spine 0'2, of the basal spines 015.

Habitat. — Central Pacific, Station 263, surface.

2. Plagoniscus euscenium, n. sp.

Spines three-sided prismatic, thorny, with dentate edges, and three to six verticils of three
short branches. Apical spine straight, with six verticils, nearly twice as long as the three curved
basal spines, each of which bears three verticils ; the basal verticils larger and ramified. Eesembles
somewhat Euscenium eucolpium, PI. 53, fig. 12, but has no latticed shell.

Dimensions. — Length of the apical spine 0'3, of the basal spines 0'16.

Habitat. — North Pacific, Station 247, surface.

1 Plagoniscus — Side — windlass ;

REPORT ON THE RADIOLARIA. 913

3. Plagoniscus cortinaris, n. sp.

Spines three-sided prismatic, straight, verticillate. Apical spine with twelve verticils, one and
a half times as long as the three basal spines, each of which bears eight verticils of three
branches. The branches are also prismatic, straight, on each edge parallel, tapering towards the
apex, hi the three basal spines forked, in the apical spine more branched. Similar to the cortinar
skeleton of Clathrocorys (PL 64, figs. 8-10).

Dimensions. — Length of the apical spine 0'24, of the basal spines 016.

Habitat. — South Atlantic, Station 338, surface.

4. Plagoniscus nassellaris, n. sp.

Spines cylindrical, curved, irregularly branched. Apical spine half as long as, and less branched
than the three basal spines, which are sigmoidal, nearly horizontally expanded in the proximal half,
descending in the distal half.

Dimensions. — Length of the apical spine 01, of the three basal spines 018.

Habitat. — West Tropical Pacific, Station 224, surface.

Genus 388. Plagonidium,^ Haeckel, 1881, Prodromus, p. 424.

Definition. — P lagonida with four equal radial spines, arising in pairs from the
two poles of a common central rod.

The genus Plagonidium and the following Plagiocarpa possess four radial spines,
like the two preceding genera. But whilst the four rods in these latter arise from a
common centre, here they arise in two pairs from the two poles of a common middle
rod ; they have therefore exactly the same form which we find in the single spicula of
some Beloidea (e.g., Thalassoxanthium furcatum, Spharozoum furcatum, &c.).
Probably the middle rod is horizontal and serves as supporting base for the central
capsule, whilst two opposite spines are directed upwards, two other downwards.

1. Plagonidium bigeminum, n. sp.

Spines straight, three-sided prismatic, four to six times as long as the common central rod,
pinnate, with four to five pairs of opposite pinnulse, the distal of which are simple, the proximal
again branched.

Dimensions,— Length of the spines 016, of the middle rod 0'032.

Habitat. — Indian Ocean, Sunda Strait (Rabbe), surface.

1 Plagonidium = Small side-article ; •jr^ttyuni^ioii.
CHALL. EXP. — PART XL. — 1886.) :Rr 115

914 THE VOYAGE OF H.M.S. CHALLENGER.

2. Plagonidium quadrigeminum, n. sp.

Spines cylindrical, curved, eight to ten times as long as the common central rod, in the distal
half forked ; the fork -branches curved, somewhat longer than the basal part.
Dimensions. — Length of the spines 018, of the middle rod 0'02.
Habitat. — Antarctic Ocean, Kerguelen Island, Station 159, surface.

Genus 389. Plagiocarpa,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — P lagonida with four unequal radial spines, arising in pairs from
the two poles of a common central rod ; one ascending apical spine opposed to three
descending basal spines.

The genus Plagiocarpa agrees with the preceding Plagonidium in the possession
of a common horizontal middle rod, the two poles of which bear two pairs of divergent
spines; but whilst in the preceding all four spines are equal, here they are differentiated
in the same manner as in Plagoniscus, which differs only in the absence of the middle
rod. The two observed and closely allied species of this genus are of peculiar interest,
since they belong possibly to the common ancestral forms of the NASSELLAEIA ; the
basal middle rod corresponds perhaps to the basal part of a sagittal ring, the apical
spine to its dorsal part, the three other spines to the basal feet (compare above, p. 902).

1. Plagiocarpa procortina, n. sp. (PI. 91, fig. 5).

Spines cylindrical, curved, thorny, three to four times as long as the common middle rod.
Apical spine and the meeting caudal spine (or the posterior basal spine) somewhat larger and with
more numerous thorns than the two paired pectoral (or anterior) spines. From the common base
of the latter arises an anterior prolongation of the horizontal middle rod, which m the sagittal plane
is curved upwards and corresponds to the sternal foot of many Cyrtellaria. An ascending
branch of this spine is opposed to a descending branch of the apical spine, both together forming an
incomplete sagittal ring.

Dimensions. — Length of the two larger spines 0'15, of the two smaller 0'12.

Habitat. — Mediterranean (Portofino near Genoa), surface.

2. Plagiocarpa procyrtella, n. sp.

Spines of form and arrangement similar to those of the preceding species, but longer and more

branched, six to eight times as long as the shorter common middle rod. The two characteristic

1 Plagiocarpa = Having its fruit (the central capsule) on the side ;

EEPORT ON THE RADIOLARIA. 915

opposed branches (the ascending branch of the basal rod and the descending branch of the apical
spine), which in the preceding species nearly compose a sagittal ring, are here absent.

Dimensions. — Length of the two larger 0'27, of the two smaller 0'21.

Habitat. — North Atlantic, Iceland (Steenstrup), surface.

Subfamily 3. HEXAPLAGIDA, Haeckel.
Definition. — P lagonida with six radial spines.

Genus 390. Hexaplagia,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — P lagonida with six radial spines, arising from one common central
point.

The genus Hexaplagia differs from the preceding genera of Plagonida in the
possession of six radial spines, diverging from one common central point. Commonly,
these six spines seem to lie opposite in pairs in three different meridian planes, and in
this case Hexaplagia may be regarded as a Plagiacantha, the three radial spines of
which are prolonged over the basal pole of the central capsule. But in other species the
six spines seem to lie in different planes. Further observations are required.

1. Hexaplagia arctica, n. sp.

Spines opposite in pairs in three diameters, crossed in the common centre, straight, three-sided
prismatic, with dentate edges. The three pairs are equal, but the upper spine of each pair only
half as long as the lower spine.

Dimensions. — Length of the upper spine 0'13, of the lower 0'27.

Habitat. — Arctic Ocean (Greenland), in the stomach of a Medusa (Olrik).

2. Hexaplagia antarctica, n. sp.

Spines opposite in pairs in three diameters, crossed in the common centre, slightly curved, three-
sided prismatic, with verticillate branches ; the three pairs are equal, but the lower spine of each
pair bears three to four verticils, each of three branches, and is two to three times as long as the
upper spine, which bears two verticils only.

Dimensions. — Length of the upper spine 012, of the lower 0'3.

Habitat. — Antarctic Ocean, Station 157, depth 1950 fathoms.

1 Hexaplagia = Six-si Jed ;

916 THE VOYAGE OF H.M.S. CHALLENGER.

3. Hexaplagia collar is, n. sp.

Spines in opposite pairs in three diameters, crossed in the common centre, straight, cylindrical,
pinnate, with three to four pairs of opposite lateral branches or regular pinnulas. All six spines are
equidistant, of equal size and similar form, and lie with their branches nearly in one horizontal
plane. Therefore they are similar to the six radial rods in the collar septum of many
Spyroidea and Cyrtoidea (e.g., Calpophcena, PI. 53, fig. 18).

Dimensions. — Length of all six spines 0'18, of their basal pinnulse 0'04.

Habitat. — East of New Zealand, Station 169, surface.

4. Hexaplagia australis, n. sp.

Spines unequal, at unequal intervals, not opposite in pairs, cylindrical, irregularly branched and
curved. In this species a definite arrangement of the six different spines could not be detected.
Dimensions. — Length of the spines 0'2 to 0'3, of their largest branches 01.
Habitat. — South of Australia, Station 160, surface.

Genus 391. Plagonium,1 Haeckel, 1881, Prodromus, p. 423,

Definition. — P lagonida with six radial spines, arising in two opposite divergent
groups from the two poles of a common central rod.

The genus Plagonium differs from the preceding closely allied Hexaplagia in the
remarkable peculiarity, that the six radial spines do not arise from one common central
point, but from the two poles of a common horizontal middle rod ; three divergent
spines on each pole. The skeleton of Plagonium exhibits therefore the same remark-
able form which is found in the isolated spicula of numerous Beloidea (e.g.,
Lampoxanthium punctatum, Sphcerozoum punctatum), and bears the same relation to
Hexaplagia that Plagonidium does to Tetraplagia.

1. Plagonium sphcerozoum, n. sp. (PL 91, fig. 6).

Spines straight and stout, three-sided prismatic, about twice as long as the common middle rod,
irregularly branched or nearly verticillate, with short thorny branches. Similar to the single
spicula of some species of Sphcerozoum and Lampoxanthium.

Dimensions. — Length of the spines 012, of the middle rod 0'06.

Habitat. — Equatorial Atlantic, Station 347, surface.

1 Plagonium = Side-article ;

REPORT ON THE RADIOLARIA. 917

2. Plagonium lampoxanthium, n. sp.

Spines irregularly curved, slender, cylindrical, six to eight times as long as the common middle
rod, in the proximal half smooth, in the distal half covered with short thorns. (Similar to
an isolated spiculum of Lampoxanthium punctatum or of Sphcerozoum variabite, PL 4 fig. 5.)

Dimensions. — Length of the spines 018, of the middle rod 0'03.

Habitat. — North Pacific, Station 240, surface.

3. Plagonium arborescens, n. sp.

Spines irregularly curved and branched, slender, cylindrical, thorny, twelve to sixteen times as
long as the middle rod ; the branches are large, arborescent, their ramules again ramified and
very thorny.

Dimensions. — Length of the spines 0'2 to 0'25, of the middle rod 0'02.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

4. Plagonium trigeminum, n. sp.

Spines straight, slender, cylindrical, four to six times as long as the middle rod, in the basal
half smooth, in the distal half arborescent, with three to four irregular verticils of ramified branches.
(Similar to a single spiculum of Sphcerozoum verticillatum, PL 4, fig. 7.)

Dimensions. — Length of the spines 015 to 0'2, of the middle rod 0'05.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

5. Plagonium distriactis, n. sp.

Spines straight and stout, three-sided prismatic, smooth, ten to twelve times as long as the
middle rod ; each on the distal end cleft into three divergent straight branches, which are again
trichotomous.

Dimensions. — Length of the spines 015 to 018, of the middle rod 0'015.

Habitat. — South Pacific, Station 288, surface.

Subfamily 4. POLYFLAGIDA, Haeckel, 1881, Prodromus, p. 424.
Definition. — P lagonida with numerous (seven to nine or more) radial spines.

Genus 392. Polyplagia,1 n. gen.

Definition. — P lagonida with numerous (seven to nine or more) radial spines,
arising from a common centre and lying in different planes.

1 Polyplagia — Manifold;

918 THE VOYAGE OF H.M.S. CHALLEJSTGEK.

The genus Polyplagia alone represents the small subfamily of Polyplagida, dis-
tinguished from the other Plagonida by the multiplication of the radial spines, the
number of which amounts to seven to nine or more. This increased number is
commonly the result of an intercalation of new spines between the three or four
primary spines ; it is sometimes also effected by stronger development of branches
of the latter, which become independent. The following five species of this genus are
very different, require further investigation, and perhaps represent different genera: —

1. Polyplagia septenaria, n. sp.

Seven radial spines, straight, three-sided prismatic, verticillate, of different sizes ; four larger
spines correspond to the four axes of a tetrahedron (running from the centre to the four corners),
each with five to six verticils of three simple slender branches ; one of these four main spines seems
to be the apical, the three others the basal spines of Plagiocarpa ; in the three meridian planes
between the latter and the former lie the three smaller spines, diverging upwards, each with two to
three verticils. (Similar to Polyplecta heptacantha, PI. 91, fig. 12, but without connection between
the branches.)

Dimensions. — Length of the four major spines 0-26, of the three minor Oil.

Habitat. — Central Pacific, Station 274, surface.

2. Polyplagia octonaria, n. sp.

Eight radial spines, straight, three-sided prismatic, of equal size, arising in two opposite groups
from the two poles of a short common middle rod (as in SpJwcrozoum arlorescens, PL 4, fig. 8, and in
other B e 1 o i d e a). The four spines of each group are divergent, six to eight times as long as the
middle rod, each spine armed with three to four verticils of thorny branches.

Dimensions. — Length of the spines 0'15, of the middle rod 0'022.

Habitat. — Indian Ocean, Cocos Islands (Eabbe), surface.

3. Polyplagia novenaria, n. sp.

Nine radial spines of equal size, straight, cylindrical, lying nearly in a horizontal plane, or
forming a very flat pyramid. Near the common central point every three spines arise from a short
common rod, so that the centre of the skeleton is triradial. Each spine bears towards the apex two
divergent straight lateral branches. This species may have been derived from Plagiacantha arach-
noides by shortening and reduction of the basal parts of the three original branched primary spines.

Dimensions. — Length of the nine spines 0'24, of the three basal rods 0'02.

Habitat. — North Atlantic, Faeroe Channel (Gulf Stream), John Murray, surface.

4. Polyplagia duodenaria, n. sp.

Twelve radial spines of equal size, arising from a common central point, and diverging in
different directions. The twelve spines are very large, opposite in six pairs, cylindrical, longitudinally

REPORT ON THE RADIOLARIA. 919

striped (the expression of concentric lamellae), and with spinulate surface, covered with innumerable
small thorns. The basal quarter of each spine is straight and simple, the second quarter twice
forked, and these four fork-branches are again in the outer half of the spine richly forked or
ramified, with diverging, slightly curved thin branches ; each of the twelve spines with about sixty
to eighty terminal branches, the ends of which seem to fall into a spherical face. The position of
this remarkable species in this family is doubtful

Dimensions. — Length of the spines 012 to 016, of the simple basal part 0'04.

Habitat. — South Pacific (off Juan Fernandez), Station 299, surface.

5. Polyplagia viminaria, n. sp.

Numerous (sixteen to twenty or more) radial spines of about equal size, arising from a common
central point and diverging in different directions, richly and more or less irregularly branched.
The ends of the numerous small branches seem to fall into a spherical face. The large spines of
this species have the same form and structure as in the preceding, nearly allied species, but are
more numerous and more irregularly branched and disposed.

Dimensions. — Length of the spines 0'2 to 0'25, of the simple basal part 0'05.

Habitat. — North Pacific, Station 241, surface.

Family XL VII. PLECTANIDA, Haeckel.

Plectanida, Haeckel, 1881, Prodromus, p. 424.

Definition. — P lectoidea with a wattled skeleton, composed of the meeting and
united branches of radial spines, which arise from a common central point or central rod,
and protect the partly enclosed central capsule.

The family Plectanida comprises those NASSELLARIA in which the skeleton is
composed of radial spines, arising from a common centre, and of a loose wickerwork,
produced by concrescence of the meeting branches of those spines. This rudimentary
wattled skeleton is either quite irregular or only slightly regular, but it never assumes
the form of a complete lattice-shell, as in the Cyrtellaria (the Spyroidea,
Botryodea, and Cyrtoidea), nor does it exhibit a ring (as in the Stephoidea).
The central capsule is partly or wholly protected, and often entirely enclosed by the
wattled skeleton.

Three species only of Plectanida have been hitherto known. The first described form
is Plectophora arachnoides, which its discoverer Claparede observed in a living state in
1855 on the western coast of Norway, and considered as a mere variety of his Plagia-
cantha arachnoides. Two other species were afterwards observed in the Mediterranean,
Polyplecta dumetum, 1856, by Johannes Miiller (united by him with Acanthodesmia)
and Polyplecta polybrocha by myself in 1864. Many new forms are found in the

920 THE VOYAGE OF H.M.S. CHALLENGER.

collection of the Challenger, so that we may here distinguish eight genera and twenty-
seven species.

The family Plectanida may be divided into four different subfamilies, according to
the number of the radial spines which compose the skeleton. These four subfamilies,
as also the genera contained in them, correspond exactly to the four subfamilies of
Plagonida, from which they have originated : Triplectida with three, Tetraplectida
with four, Hexaplectida with six, and Polyplectida with numerous (seven to nine or
more) radial spines. These spines are usually united (as in the corresponding
ancestral Plagonida) in one common central point, upon which rests the basal pole of
the central capsule, with the porochora. More rarely (in the genera Periplecta and
Plectanium) the spines arise in two opposite groups (each of two or three spines) from
the two poles of a common horizontal central rod, which supports the overlying
porochora of the central capsule.

The different genera of Plectonida, which are enumerated in the following synopsis,
correspond so exactly to the different genera of Plagonida described above, that probably
each of the former has arisen from a corresponding genus of the latter. The only
difference between the two is, that in all Plagonida the branches and ramules of the radial
spines end freely, without growing together, whilst in all Plectanida the meeting ends of
the neighbouring spines grow together and so produce a loose and irregular wickerwork.
Therefore the latter constantly possess meshes, which are missing in the former. As
soon as any form of Plagonida begins to produce meshes by concrescence of meeting
branches of the spines, it passes over into a corresponding form of Plectanida. The
loose wickerwork or wattlework so produced is sometimes very irregular, at other times
more or less regular ; but it never assumes the regular form of a complete lattice-shell,
as in the Cyrtellaria (Spyroidea, Botryodea, and Cyrtoidea). The
general differences which this wickerwork exhibits in the different genera of Plectanida
have been already described above (compare pp. 900—904).

The Central Capsule of the Plectanida agrees perfectly with that of the ancestral
Plagonida, as well in general form and structure as in the peculiar topographical relation
to the radial spines (compare above, p. 905). A slight difference between the two
families is effected by the higher development of the skeleton in the Plectanida. Since
the branches of the radial spines in this family become united and form a loose wicker-
work, the central capsule becomes more or less enclosed by the latter, and more
perfectly protected, than in the Plagonida, where the branches remain free. In this
respect the Plectanida approach more nearly to the Cyrtoidea with which they are
connected by such transitional forms as Plectaniscus .and Periplecta on the one hand,
Cladoscenium and Pteroscenium on the other.

REPORT ON THE RADIOLARIA.

921

I. Subfamily

Triplectida.
Three radial spines.

II. Subfamily

Tetraplectida.
Four radial spines.

III. Subfamily

Hexaplectida.
Six radial spines.

IV. Subfamily

Polyplectida.
Numerous radial spines.

Synopsis of the Genera of Plectanida.
Three spines lying in one horizontal plane, .
Three spines corresponding to the edges of a flat pyramid,

{All four spines equal,
One apical spine opposed to
three basal spines,

Four spines arising in two pairs from the poles of a common
central rod; one apical spine different from three basal
spines, .......

Six spines arising from one common central point, .

Six spines arising in two opposite groups from the poles of
a common central rod, .....

Numerous (seven to nine or more) radial spines arising from
a common centre (either a central point or a branched
rod), .......

393. Triplecta.

394. Plectophora.

395. Tetraplecta.

396. Plectaniscus.

397. Periplecta.

398. Hexaplecta.

399. Pledanium.

400. Polyplecta.

Subfamily 1. TKIPLECTIDA, Haeckel, 1881, Prodromus, p. 424.
Definition. — P lectanida with three radial spines.

Genus 393. Triplecta,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — P lectanida with three radial spines, arising from one common
central point and lying in one horizontal plane.

The genus Triplecta is the simplest and most primitive of the Plectanida, and
may therefore be regarded as the prototype of this family. The skeleton represents
a triangular lattice-plate with three radial beams. On the central union of the latter
rests the oral pole of the central capsule. Since the axis of the latter is vertical,
the lattice-plate must be horizontal, serving for the expansion of the pseudopodia.
Triplecta has arisen from Triplagia by union of the branches of its three radial
spines. In the simplest case only three large meshes are formed, corresponding prob-
ably to the three cortinar meshes in the collar septum of many Cyrtellaria.

1. Triplecta triangulum, n. sp.

Spines straight, equal, smooth, cylindrical, each in the basal half with one pair of divergent
straight lateral branches. The opposed branches of every two neighbouring spines are united by a

1 Triplecta = Hunting net with three beams ; TJ/J, TXSXTIJ.

(ZQOL. CHALL. EXP. PABT XL. — 1886.) Rr 116

922 THE VOYAGE OF H.M.S. CHALLENGER.

thin convex bow. In this way arises a very simple, equilateral triangular skeleton, with three equal
large meshes.

Dimensions. — Length of the spines 014, sides of the triangle 016.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

2. Triplecta triactis, n. sp. (PL 91, fig. 7).

Spines straight, equal, three-sided prismatic, pinnate, each with three to four pairs of opposite
slender pinnulse or lateral branches ; the pinnules of each spine are correspondingly parallel to the
main rods of the other two spines. All pinnulse branched and connected by a few slender bows,
marking the sides of a regular triangle.

Dimensions. — Length of the spines 015, sides of the triangle 017.

Habitat.— Central Pacific, Station 272, depth 2600 fathoms.

Genus 394. Plectophora,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — P lectanida with three radial spines, arising from one common
central point and corresponding to the edges of a three-sided pyramid.

The genus Plectophora has been derived from Plagiacantha by union of the meeting
neighbouring branches of the three radial spines, and exhibits therefore to it the same
relation that Triplecta bears to Triplagia. The loose framework so produced corre-
sponds to the three sides of a flat pyramid and supports the central capsule.

\

1. Plectophora triomma, n. sp.

Spines equal, straight, three-sided prismatic, thorny, connected by three convex bows, the
meeting branches of lateral spines arising in one pair from the middle part of each spine. There-
fore the skeleton exhibits three large ovate meshes only.

Dimensions. — Length of the spines 012, of the meshes 0'08.

Habitat. — North Pacific, Station 238, surface.

2. Plectophora arachnoides, Haeckel.

Plagiacantha arachnoides, var., Claparfede, 1858, Etudes sur les Infusoires et les Ehizopodes,
p. 462, Taf. xxii. fig. 9.

Spines straight, cylindrical, trifid, with one pair of lateral branches. The nine diverging,
straight, and smooth branches are connected in the distal part by slender concave bows, so that the
whole skeleton exhibits nine wide meshes, three larger pentagonal and six smaller triangular.

Dimensions.— Length of the spines 014, of their branches 0P07.

Habitat. — North Atlantic, west coast of Norway (Claparede), surface.
1 Plectophora = Bearing a hunting net ;

REPORT ON THE RADIOLARIA. 923

3. Plectophora novena, n. sp.

Spines slightly curved, three-sided prismatic, thorny, with two pairs of lateral branches. The
six smaller distal branches end freely, whilst the six larger basal branches are connected by slender
convex bows. There are therefore nine wide meshes, as in the preceding closely allied species.

Dimensions. — Length of the spines 0'18, of the basal branches 0'08.

Habitat. — North Atlantic, Fserb'e Channel (Gulf Stream) (John Murray), surface.

4. Plectophora pyramidalis, n. sp.

Spines straight, three-sided prismatic, with three to four verticils of short lateral branches.
The branches of the basal verticils are again ramified, and form by connecting bows a delicate loose
framework, covering the three sides of a flat^ pyramid, the three edges of which are the three radial
spines.

Dimensions. — Length of the spines 0'2, base of the pyramid 016.

Habitat. — Central Pacific, Station 267, surface.

Subfamily 2. TETRAPLECTIDA, Haeckel, 1881, Prodromus, p. 424.
Definition. — P leetanida with four radial spines.

Genus 395. Tetraplecta,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — P leetanida with four equal radial spines, arising from one common
central point and corresponding to the four axes of a tetrahedron.

The genus Tetraplecta has been derived from Tetraplagia by union of the neighbour-
ing branches of the four radial spines, diverging from a common point in different
directions. In some forms of this genus the four rods seem to correspond exactly to
the four axes, which are directed from the centre of a tetrahedron towards its four
corners ; whilst in other forms the four rods and the angles between them are perhaps
not perfectly equal.

1. Tetraplecta tetrahedra, n. sp.

Spines straight, equal, three-sided prismatic, pinnate, each with three or four pairs of opposite

straight slender pinnulae or lateral branches ; the pinnulae of each side are correspondingly parallel.

1 Tetraplecta = Hunting net with four beams ;

924 THE VOYAGE OF H.M.S. CHALLENGER.

All pinnulse connected by a few slender bridges, thus producing a delicate network with irregular
rhomboidal meshes.

Dimensions. — Length of the spines 0'15, of the basal branches 0'05.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Tetraplecta quadricornis, n. sp.

Spines in the basal half straight, in the distal half slightly curved and irregularly branched,
with two to three pairs of unequal alternate lateral branches) the distal ends of which are
connected by a few slender bows, marking the six edges of an irregular tetrahedron.

Dimensions. — Length of the spines 0'22, of the basal branches 0'14.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Tetraplecta pinigera, n. sp. (PI. 91, fig. 8).

Spines three-sided prismatic, straight, or in the basal half slightly curved, verticillate ; each
spine with six to eight three-branched regular verticils, tapering gradually towards the distal end.
All branches of each spine lie parallel in three equidistant meridian planes, and are connected by
delicate parallel threads, perpendicular to the branches. Therefore the skeleton consists of four
pine-shaped trees and twelve delicate triangular wings with rectangular meshes.

Dimensions. — Length of the spines 0-25 to 0'3, of the basal branches 01 to 0-15.

Habitat.— Central Pacific, Station 271, surface.

Genus 396. Plectaniscus,1 nov. gen.

Definition. — P lectanida with four unequal radial spines, arising from one
common central point ; one vertical or apical spine opposed to three divergent or basal
spines.

The genus Plectaniscus has probably been derived from Plagoniscus by reticular
union of the neighbouring branches of the four radial spines, and exhibits therefore to it
the same relation that Tetraplecta bears to Tetraplagia. Whilst in these two latter
genera the four spines are equal, in the two former genera there is an important differ-
ence between a vertical spine (or apical horn) and three divergent (commonly larger)
spines, corresponding to the three basal feet of the triradiate NASSELLARIA. Perhaps,
therefore, Plectaniscus is one of the remotest ancestors of the latter ; but differs in the
absence of a complete lattice-shell.

1 Plectaniscus = Shell of wickerwork ;

REPORT ON THE RADIOLARIA. 925

1. Plectaniscus cortiniscus, n. sp. (PI. 91, fig. 9).

Spines straight, three-sided prismatic, with three to four verticils of short perpendicular
branches ; the branches of the distal verticils are simple and free, those of the proximal verticils
again ramified and connected by an arachnoidal network of delicate threads. The vertical apical
spine (or horn) is scarcely one-third or half as long as the three divergent basal spines (or feet), and
the angle between it and the latter is smaller.

Dimensions. — Length of the apical spine 0'05 to 01, of the three basal spines 018 to 0'2.

Habitat. — North Pacific, Station 244, surface.

2. Plectaniscus tripodiscus, n. sp.

Spines curved, cylindrical, with a variable number of irregular branches, which in the distal
half of the spines are free, in the basal half again ramified and connected by a loose spongy frame-
work. The apical spine is shorter and simpler, nearly straight, less ramified.

Dimensions. — Length of the apical spine 01, of the three basal spines 015 to 018.

Habitat. — North Pacific, Station 238, surface.

3. Plectaniscus archiscenium, n. sp.

Spines slightly curved, three-sided prismatic, with two to three verticils of short curved
branches. The vertical apical spine is about twice as long as the three basal spines, and connected
with them by an irregular loose framework. The three basal spines are connected together only by
a simple ring, so that between them remain three large collar holes, like those of the similar and
closely allied Archisceniwn yuadrispinum (PL 53, fig. 11).

Dimensions. — Length of the apical spine 0'32, of the three basal spines 018.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

4. Plectaniscus cladoscenium, n. sp.

Spines curved, three-sided prismatic. The three basal spines pinnate, with four to five pairs of
opposite curved pinnulae ; the distal pairs are simple and free, the basal pairs branched and
connected by an irregular delicate framework, which together with the apical spine forms a spongy
cap-shaped shell, similar to Cladoscenium. Apical spine about half as long, simple.

Dimensions. — Length of the apical spine 01, of the three basal spines 018.

Habitat. — Central Pacific, Station 274, surface.

5. Plectaniscus clathrocorys, n. sp.

Spines straight, three-sided prismatic, with seven or eight verticils of ramified branches, which
in the basal half are connected by an irregular loose framework. In the distal half each of the
three divergent basal spines (or feet) is connected with the longer apical spine (or horn) by a

926 THE VOYAGE OF H.M.S. CHALLENGER.

fenestrated triangular lattice wing. Therefore the skeleton becomes very similar to Clathrocorys
(PL 64, figs. 8-10), but wants the regular central cephalis.

Dimensions. — Length of the apical spine 0'2, of the basal spines 0'14.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 397. Periplecta,1 Haeckel, 1881, Prodromus, p. 424.

Definition — P lectanida with, four unequal radial spines, arising in pairs from
the two poles of a common central rod ; one ascending apical spine opposed to three
descending basal spines.

The genus Periplecta has probably been derived from Plagiocarpa (by concrescence
of the meeting spine branches), and has the same important relation to a part of the
triradial Stephoidea (Cortina, &c.) and Cyrtoidea (Pteroscenium, &c.). It
differs from the latter only in the fact that the loose irregular framework connecting
the bases of the four cortinar spines is not a regular lattice-shell.

1. Periplecta cortina, n. sp. (PI. 91, fig. 10).

Spines of very different size and shape, three-sided prismatic. The apical spine (or horn) is
larger, nearly straight, and bears a verticil of three large divergent branches, which are again
ramified. The three basal spines (or feet) are curved, pinnate, each with three to five pairs of
opposite simple curved branches. A small common central rod separates the two united pectoral
feet from the two other spines (the caudal foot and the apical horn). The three basal feet are
connected by three convex bows composing a horizontal collar ring, and since the central rod is
prolonged between the pectoral feet to the ring, a very remarkable collar septum is formed with four
cortinar meshes. Above this septum an irregular spongy shell, including the central capsule, is
formed by a delicate framework, interwoven between the apical horn and the three basal feet.

Dimensions. — Length of the apical spine 0'25 to 0'3, of the three basal spines 0'15 to 0'2.

Habitat. — Central Pacific, Station 271, surface.

2. Periplecta pteroscenium, n. sp.

Spines of very different size and shape, three-sided prismatic, verticillate. The apical spine (or
horn) with ten to twelve verticils, is one and a half times as long as the three basal spines (or feet),
which bear six to eight verticils only; each verticil with three branches which by communicating
ramules form a loose irregular wickerwork. Similar to Pteroscenium pinnatum, PL 53, figs. 14-16,
but without a regular lattice-shell. A short basal central rod separates two equal (pectoral) spines
from two unequal spines, the larger of the latter is the apical, the shorter the caudal spine.

Dimensions. — Length of the apical spine 0'26, of the three basal spines O'l7.

Habitat. — Central Pacific, Station 274, surface.

1 Periphcta = Surrounded by a hunting net ; «•£{/, •a^tx.Tti.

REPORT ON THE RADIOLARIA. 927

3. Periplecta monocyrtis, n. sp.

Spines of nearly equal size and shape, cylindrical, irregularly branched. The apical spine is
straight, more branched and nearly twice as long as the three basal spines. All four spines in the
basal third connected by a loose spongy framework, approaching the form of some Monocyrtida.

Dimensions. — Length of the apical spine 0'24, of the basal spines 0'13.

Habitat. — Central Pacific, Station 274, surface.

Subfamily 3. HEXAPLECTIDA, Haeckel.
Definition. — P lectanida with six radial spines.

Genus 398. Hexaplecta^ Haeckel, 1881, Prodromus, p. 425.

Definition. — P lectanida with six radial spines, arising from one common central
point.

The genus Hexaplecta has probably been derived from Hexaplagia by concrescence
of the meeting branches of the six spines, and therefore has to it the same relation
that Plectophora bears to Plagiacantha. The two species here described represent
perhaps two different genera, since in the first all six spines are equal, opposed in pairs,
in the second different in pairs (three upper smaller and three lower larger).

1. Hexaplecta triaxonia, n. sp.

Spines equal, opposite in three crossed pairs, straight, three-sided prismatic, thorny, in the
distal half with three leaf-shaped, dentate edges, in the basal half with three verticils of slender
branches, which are connected by parallel threads, and so form an arachnoidal network with rect-
angular or rhomboidal meshes.

Dimensions. — Length of the spines 0'22, of their basal branches 0'06.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

2. Hexaplecta tricladonia, n. sp.

Spines unequal, three larger spines (in the lower half of the body) being opposite to three
smaller spines (in the upper half). The latter are nearly horizontally expanded, each bearing three
straight divergent branches. The larger are stronger, twice as long and armed with three verticils,
each of three branches. All six spines are slender, three-sided prismatic. Their branches are very
thin, thread-shaped, and form by their union a loose network with irregular polygonal meshes.

Dimensions. — Length of the larger spines 0'25, of the smaller 0'12.

Habitat. — South Pacific, Station 291, surface.

1 Hexaplecta = Hunting net with six beams ; %!•

928 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 399. Plectanium? Haeckel, 1881, Prodromus, p. 424.

Definition. — P 1 e c t a n i d a with six radial spines, arising in two opposite divergent
groups from the two poles of a common central rod.

The genus Plectanium has been derived from Plagonium by concrescence of the
meeting branches, and bears therefore to it the same relation that the preceding
Hexaplecta exhibits to Hexaplagia. Whilst in these two latter genera the six spines
arise from a common central point, they arise here in two divergent groups from the
two poles of a horizontal common middle rod, similar to the spicula of many Beloidea.

1. Plectanium trigeminum, n. sp. (PL 91, fig- H)-

Spines straight and stout, six to eight times as long as the common middle rod, three-sided
prismatic ; in the distal half thickened, with three divergent terminal thorns ; in the basal half
with three to four verticils of thin lateral branches, which are again ramified, and by their united
threads produce an irregular loose framework.

Dimensions. — Length of the spines 0'25, basal breadth 0'005, terminal breadth 0'02; length of
the middle rod 0'03.

Habitat. — North Pacific, Station 244, surface.

2. Plectanium ovodimare, n. sp.

Spines straight and stout, three-sided prismatic, about four times as long as the common middle
rod, gradually thinned towards the distal end ; in the basal half with two to three verticils of
forked branches, which are dichotomously ramified, and by their united threads form a loose ovate
framework.

Dimensions. — Length of the spines 017, of the middle rod 0'04.

Habitat. — North Pacific, Station 236, surface.

3. Plectanium sphcerozoum, n. sp.

Spines straight, cylindrical, ten to twelve times as long as the common middle rod, with six to
eight verticils of thorny branches, tapering towards the distal end; the branches of the verticils
are simple in the distal half, again ramified in the basal half, and here connected together by
irregularly branched threads forming a loose framework. (Resembles one spiculum of SpJuxrozoum
verticillatum, PI. 4, fig. 7, but is more richly branched, with united ramules.)

Dimensions. — Length of the spines 0-2, of the middle rod OD1.

Habitat. — Central Pacific, Station 266, surface.

1 Plectanium = Small wickerwork or network ;

REPORT ON THE RADIOLARIA. 929

Subfamily 4. POLYPLECTIDA, Haeckel, 1881, Prodromus, p. 424.
Definition. — P lectanida with numerous (seven to nine or more) radial spines.

Genus 400. Polyplecta,1 Haeckel.

Definition. — P lectanida with numerous (seven to nine or more) radial spines,
arising from a common centre and lying in different planes.

The genus Polyplecta comprises provisionally all Plectanida possessing seven or
more radial spines, united in the centre of the framework. It may be derived from
Polyplagia by meeting and concrescence of the free branches. But as in the latter
genus, here also the few observed species are very different, perhaps of different origin,
and may be afterwards better separated as representatives of diverse genera.

1. Polyplecta heptacantha, n. sp. (PI. 91, fig. 12).

Heptaplegma heptacantha, Haeckel, 1882, MS.

Seven unequal spines divergent from one common central point, slender, slightly curved, three-
sided prismatic. Four spines are much larger, twice to three times as long and as thick as the
three smaller spines. One of the four larger spines is directed upwards (as " apical horn "), whilst
the three others diverge downwards (as " basal feet "). Each of the four larger spines bears five to
seven equidistant verticils of three divergent branches, the proximal of which are branched, the
distal simple. The three smaller spines lie nearly horizontally, midway between the odd apical
spine and the three basal spines, and in the same meridian planes with them ; each bears one
verticil of three divergent branches. All the branches are united by arachnoidal threads, composing
a loose wickerwork with irregular, generally quadrangular meshes.

Dimensions. — Length of the four larger spines 0'27 to 0'33, of the four smaller O'l to 0'14.

Habitat. — Central Pacific, Station 271, surface.

2. Polyplecta enneacantha, n. sp.

Enneaplegma enneacantha, Haeckel, 1881, Prodromus, p. 425.

Nine equal and equidistant, straight, cylindrical radial spines, lying nearly in one plane, arise
from an irregular spongy central framework ; six of them seem to be secondary, intercalated
between three equidistant primary spines, which are united in the centre. (This species resembles
in the nine-radial structure the remarkable Enneaphormis rotula, PL 57, fig. 9, and may perhaps
be derived from a similar species ; but it has no regular latticed shell.)

Dimensions. — Length of the spines 0'22, diameter of the framework O'l1?.
.Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

1 Po%)Z«cta = Much entwined ; TroTi^xsxrof.

(ZOOL. CHALL. EXP. — PART XU — 1886.) .Rr 11, 7

930 THE VOYAGE OF H.M.S. CHALLENGER.

3. Polyplecta decacantha, n. sp.

/

Pentaplegma decacantha, Haeckel, Prodromus, p. 425.

Ten radial spines, curved, cylindrical, irregularly branched, diverge in different directions
and seem to arise in pairs from an irregular central framework, in the centre of which five
primary spines are united ; the latter correspond probably to the five spines of Pentaspyris, &c.
The density of the spongy central framework did not allow of an accurate investigation, and makes
it doubtful whether this species is not a Spongiomma.

Dimensions. — Length of the spines 0'3 to 0'4, diameter of the framework 0'18.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

4. Polyplecta polybrocha, Haeekel.

1 Acanthodesmia polybrocJia, Haeckel, 1865, Zeitschr. f. wiss. Zool., Bd. xv. p. 368, Taf. xxvi.

fig. 3.
Plegmosphcera polybrocha, Haeckel, 1881, Prodromus, p. 455.

Numerous (twenty to thirty or more) radial spines, thin, cylindrical, curved and irregularly
branched, arising from an irregular central spongy framework, are connected by numerous slender
arches. The specimen observed by me in 1880 in Portofino was a true Polyplecta, with three
primary spines centrally united, between which numerous other spines were intercalated. The
similar specimen, however, observed in 1864 in Villafranca, and figured, loc. cit., was perhaps a
Plegmosphcera.

Dimensions. — Length of the radial spines 0'05 to O'l, diameter of the framework 016.

Habitat. — Mediterranean (Villafranca, Portofino), surface.

5. Polyplecta dumetum, Haeckel.

Acanthodesmia dumetum, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 30, Taf. i.
fig. 3.

Numerous (ten to twelve or more) radial spines, thin and straight, with a few straight lateral
branches, diverge in different directions and are connected by a few slender curved arches. Some
similar forms, but more developed, with numerous branches and curved rods, are found in the
Pacific Eadiolarian ooze, and represent probably different species.

Dimensions. — Length of the radial spines 0'05 to 0'08, of the branches 0'02 to 0'03.

Habitat. — Mediterranean, French shore (Cette and Saint Tropez), Johannes Miiller, surface

REPORT ON THE RADIOLARIA. 931

Suborder III. STEPHOIDEA, Haeckel.

Stephoidea vel Stephida, Haeckel, 1881, Prodromus, p. 444.
Acanthodesmida (sensu ampliori), Biitschli, 1882, Zeitschr. f. wiss. Zool.,
vol. xxxvi. p. 495.

Definition. — NASSELLABIA without complete lattice -shell, with a skeleton composed
of one or more simple rings, which may be united by a loose framework and are separated
by large openings or gate's. One primary or sagittal ring, determining the sagittal or
median plane of the bilateral body, encloses the monaxonian central capsule.

The suborder Stephoidea, hitherto known by a few species only of " Acantho-
desmida," comprises a large number of interesting NASSELLARIA (now more than two
hundred species), which possess peculiar interest for the morphology and phylogeny
of this legion. The monaxonian central capsule of the Stephoidea is surrounded
either by one simple ring or by a complex system of several loosely connected rings ;
these may be united by a loose framework of connected branches, but never produce a com-
plete lattice-shell, as is constantly the case in the Spyroidea, Botryodea, and
Cyrtoidea. Therefore there remain between the parts of the connected rings a few
large openings which we call "gates," separating them from the numerous small "pores"
of the complete lattice-shells. In the most simple case, if only one ring be formed,
there is also present only one " gate," the aperture of this simple ring.

The first known species of Stephoidea were observed in the Mediterranean by
Johannes Miiller in 1856, and described and figured in his last treatise (1858) under
the names Lithocircus annularis (loc. cit., Taf. i. fig. 1) and Acanthodesmia vinculata
(loc. cit., Taf. i. figs. 4—7). In the following year I myself observed two other living
species in the Mediterranean, and described them in my Monograph (1862, pp. 268,
270) as Zygostephanus miilleri (Taf. xii. fig. 2) and Prismatium tripleurum (Taf. iv.
fig. 6). For these four longest known Stephoidea I founded the new family
of Acanthodesmida (loc. cit., p. 265), but united with them two other similar genera
which I afterwards separated : — Plagiacantha (belonging to the Plectoidea) and
Dictyocha (belonging to the PH^EODAKIA).

When, in 1876, I received the rich material of the Challenger collection, I was
astonished to find in it an enormous number of new, similar, and partly very interest-
ing "Acanthodesmida," which were afterwards arranged in my Prodromus (1881,
p. 444) in thirty-eight different genera and four " subfamilies," all united in one
single large family, " Stephida or Monopylaria cricoidea." I retain here this natural
group in the same sense, but give to it the rank of a " suborder," separating at the
same time its four subfamilies as substantial " families." Since the names of the

932 THE VOYAGE OF H.M.S. CHALLENGER.

latter, proposed in the Prodromus, were not quite suitable, I replace them here by the
following more convenient names : —

1. Family Stephanida ( = Monostephida, 1881, p. 447). Skeleton entirely formed

by one simple ring (the primary vertical sagittal ring). The only " gate "
is the simple aperture of the ring.

2. Family Semantida ( = Dyostephida, 1881, p. 446). Skeleton composed of

two rings, perpendicular to one another ; the primary vertical sagittal
ring bears at the base a horizontal basal ring ; between the two rings
two or more " basal gates remain."

3. Family Coronida ( = Triostephida, 1881, p. 445). Skeleton composed of two

crossed vertical or meridional rings, perpendicular to one another — the
primary sagittal ring and the secondary frontal ring. Commonly the two
vertical rings are united at the base by a horizontal basal ring, and
between them remain two or more " basal gates."

4. Family Tympanida ( = Parastephida, 1881, p. 446). Skeleton composed of

two parallel horizontal rings, an upper mitral ring, and a lower basal ring,
both connected by vertical or divergent columellae, which are parts of
vertical rings (primary sagittal, and secondary frontal ring).

The peculiar structure of the central capsule of the Stephoidea, and their
character as true MONOPYLEA, were first recognised by Eichard Hertwig, who in
1879, in his Organismus der Eadiolarien, gave an excellent detailed description of it
(loc. cit., pp. 68—72, Taf. vii. figs. 4, 5). He also pointed out the near affinity of these
" Acanthodesmida " with the Spyroidea or Zygocyrtida, uniting the latter with the
former family.

A fuller explanation of this affinity, and of the great morphological and phylo-
genetic importance of the " Acanthodesmida," as ancestral forms of the Spyroidea
and Cyrtoidea, was given in 1882 by Butschli (Zeitschr. f. wiss. Zool., vol. xxxvi.
pp. 495—501). He described in detail some important fossil forms of Acanthodesmida
as different species of " Stephanolithis," a name which Ehrenberg had employed for
various ring-like fragments of Eadiolarian shells, sponges, and other fossil bodies.
The four fossil species which Butschli described represent four different genera of
Stephoidea, viz., Semantis (spinescens), Semantrum (mulleri], Semantidium
(haeckelii), and Tristephanium (hertivigii). On the phylogenetic conclusions, derived
from these accurate observations, compare above, p. 893, &c. The topographical signifi-
cation of the parts, employed by Butschli, is contrary to mine ; he calls my dorsal
side the " anterior," and my ventral side the " posterior."

The geometrical fundamental form of the body in nearly all Stephoidea (with
few exceptions) is distinctly bilateral or " dipleuric," so that we can easily distinguish the

REPORT ON THE RADIOLARIA. 933

three different dimensive axes : the principal axis with different apical aad basal poles,
the sagittal axis with different dorsal and ventral poles, and the lateral axis with equivalent
right and left poles. In only a few genera this bilateral symmetry is not expressed, and
a simpler, more regular fundamental form appears. The latter may be either primary
(in the monaxonian Archicircus and Lithocircus) or secondary, afterwards acquired (in
the octahedral Trissocircus and Trissocydus, the cubical Lithocubus, the prismatic
Eutympanium, and some other forms).

The most important element of the skeleton, with which its formation begins, in
all Stephoidea is the simple primary or sagittal ring, lying vertically in the
sagittal or median plane of the body and surrounding the monaxonian central capsule.
This sagittal ring is the only essential element of the skeleton in all Stephanida, and is
completely preserved in all Semantida, also in the greater part of the Coronida and
Tympanida. It is partially reduced in the small groups of the true Acanthodesmida
(subfamily of Coronida) and the Dystympanida and Eutympanida (subfamilies of
Tympanida). Here only the vertical parts of it are preserved (dorsal and ventral rod),
whilst the horizontal parts are lost (mitral and basal rod).

The sagittal ring, lies constantly in the vertical median plane of the body, and.
therefore divides the enclosed central capsule into a right and a left half. It is rarely
regular or subregular, commonly dipleuric or distinctly bilateral, so that we may easily
distinguish its dorsal and ventral, apical and basal parts. The most important of these
four parts or " rods " is the " basal rod " or the inferior part, because here the ring is in
closer connection with the central capsule and its "porous area"; here peculiar spines
or branches are commonly developed, which even on the isolated ring immediately
determine the basal pole. The opposite upper part, or the " mitral rod," is also often
distinguished by peculiar appendages. The posterior part, or the " dorsal rod " (the
anterior rod, a, in the description of Biitschli), is commonly more straight, often quite
vertical. The opposite anterior part, or the " ventral rod " (the posterior rod, &, of
Biitschli), is usually more convex, and often strongly curved or semicircular,

AVhilst this dipleuric or bilateral (commonly obliquely ovate or nearly triangular) form
of the sagittal ring is distinctly preserved in by far the greater number of Stephoidea,
it is replaced in some few genera by a more regular, amphitheet, diphragmatic, or biradial
form. In this case we may often suppose a primary regularity to exist, the dorsal and
ventral parts being not yet differentiated, as in Archicircus and Lithocircus, Zygo-
stephanus and Protympanium, and perhaps also in some other forms. But in other cases
the regularity is, on the contrary, secondary, being derived from original bilateral forms.

The rod of the sagittal ring is either cylindrical (with circular transverse section) or
angular (commonly with triangular transverse section). In nearly all Stephoidea
(with very few exceptions) branches or apophyses are developed from the ring,
regular^ disposed and often of very great morphological importance. Commonly "these

934 THE VOYAGE OF H.M.S. CHALLENGER.

apophyses are developed in pairs, growing symmetrically on both sides of the ring.
The most important of these apophyses are : — (l) basal apophyses, arising from the
basal pole of the ring ; (2) mitral apophyses, arising from the apical pole ; (3) dorsal
apophyses, arising from the middle of the dorsal rod ; and (4) ventral apophyses,
arising from the middle of the ventral rod. The two former arise in the principal axis,
the two latter in the sagittal axis of the body. Very frequently the latter pair is
replaced by two pairs of transverse branches, one inferior (mandibular) and one superior
(orbital). The apophyses of the ring are either simple or branched, often very large,
richly ramified, and give origin to a number of further products.

Whilst in the Stephanida the primary sagittal ring alone represents the whole
skeleton, it produces in all other Stephoidea one or more secondary rings. The
most important of these is the horizontal basal ring, appearing first in the Semantida
(PL 92). From the base of the sagittal ring there arise in the horizontal basal plane
two pairs of lateral branches or " basal apophyses." The curved opposite branches of
the corresponding pairs become united on each side of the primary ring (right and
left), and so produce a second, horizontal ring, perpendicular to the former. This basal
ring encloses two paired basal gates, which are enclosed on the medial side by the basal
rod of the sagittal ring, and on the lateral side by two united apophyses (Semantis,
PI. 92, figs. 1, 2). These two primary basal gates are of the greatest morphological
importance; we call them the "jugular gates or jugular pores " (in the description of
Biitschli, the pores I, loc, cit., p. 498). The dorsal pair of basal apophyses (on their
posterior edge) are the coracal rods, e (rods e of Biitschli) ; the opposite ventral pair
(on their anterior edge) are the clavicular or furcular rods, f (rods el of Biitschli); compare
Pis. 92-95, and their explanation.

The skeleton of Semantis, the prototype of the Semantida, thus assumes the
characteristic form of a signet-ring. The basal ring enclosing the two jugular pores
corresponds to the seal-plate. It is commonly more or less horizontal ; but often the
apophyses descend obliquely (PL 92, figs. 1, 2, 13, &c.), more rarely laterally
(PL 29, fig. 11). The further development of this typical form is essentially effected
by the production of new basal pores in the horizontal seal-plate. In Semantrum
(PL 92, figs. 3, 4, 5) we find already four basal gates. Behind the jugular gates is
formed a second pair, the " cardinal gates " (pores II of Biitschli). These are enclosed
on the anterior margin by the coracal rods (e), on the posterior margin by the scapular
rods (d), a third pair of basal apophyses, arising behind the former from the sagittal
ring and uniting with them (the rods e2 of Biitschli). Commonly the two posterior, or
cardinal gates are much larger than the two anterior, jugular gates. This characteristic
basal plate of Semantrum, with two pairs of basal pores, is of the greatest morphological
importance, as it is inherited in by far the greater number of the NASSELLAEIA, though not
so generally as Biitschli supposes. The basal ring of Semantrum is either more circular

REPORT ON THE RADIOLARIA. 935

or elliptical, or more polygonal, and is connected with the basal rod of the sagittal
ring by three pairs of radial apophyses, the anterior furcular, the middle coracal, and the
•posterior scapular rods.

A third important form of Semantida is Semantidium (PL 92, figs. 6, 7). Here
we find three pairs of basal pores in the seal-plate ; the third pair, newly formed,
consists of the cervical gates (e), bounded in front by the scapular rods (cZ),
behind by a fourth pair of basal apophyses, the cervical rods.

The basal apophyses of the sagittal ring are not only of great morphological
importance, because they produce by their union three typical pairs of basal gates or
" collar pores," but also because their prolongations often appear as typical basal feet.
The distal prolongations of the coracal rods appear in Semantiscu-s (PL 92, figs. 16—18)
as two pectoral feet, those of the scapular rods as two tergal feet, whilst the opposite
prolongations of the basal rod of the sagittal ring appear as two " sagittal feet " (in front
an anterior or sternal, and behind a posterior or caudal foot). In the typical Cortiniscus
(PL 92, figs. 11—13) only three feet are developed; an odd caudal and two paired
pectoral feet (compare above, p. 891). The typical basal ring of the Semantida, with its
paired basal gates (Semantis), reappears in the majority of the Coronida, differing from
the former in the development of a second vertical ring, which lies in the frontal plane
(perpendicular to the sagittal ring), and which we therefore call the frontal ring. In only
one small group of the Coronida the basal ring is absent, namely, in the Zygostephanida,
and here the frontal ring appears in the simplest form, as a complete elliptical meridian
ring, crossing the sagittal ring perpendicularly on the -two poles of the main axis
(Zygostephanus, PL 93, figs. 1—4). Four large lateral gates between the two rings
remain open. This form may be derived directly from the Stephanida in the following
way ; from both poles of a simple sagittal ring there arise two opposite lateral apophyses,
which in the frontal plane become curved one towards the other, and united in the poles
of the transverse axis. The basal apophyses would be the coracal rods. But it is also
possible that Zygostephanus was derived from Semantis by the loss of the furcular rods.

The three typical rings (or the " dimensive rings ") of the Stephoidea appear
in their most complete form in the subfamily Trissocyclida (PL 93, figs. 7, 13).
Here all three rings are undivided and completely developed in the three dimensive
planes, perpendicular one to another. Between them there remain eight large open
gates ; the four superior are the four " lateral gates " of Zygostephanus, the four
inferior are the four basal gates of Semantrum. The four latter are originally much
smaller than the four former; but in Trissocircus and Trissocyclus (PL 93, figs. 10—12)
they reach the same size. Therefore all eight gates are here of equal form and similar
size, and the basal ring, now a true equatorial ring, divides the two meridional rings
into two equal halves.

In the Eucoronida, a third subfamily of Coronida, the sagittal and the basal rings

936 THE VOYAGE OF H.M.S. CHALLENGER.

are complete, but the frontal ring is incomplete, its basal part being wanting (PL 82, figs.
4—6). Therefore we find here six large gates between the three rings; four upper lateral
gates (between the two crossed vertical rings) and two lower basal gates (between the
basal rod of the sagittal ring and the two halves of the basal ring). Eucoronis, the type
of this subfamily, may be derived either directly from Semantis by development of a
frontal ring, or from Tristephanium by loss of the basal part of the frontal ring.

A quite simple basal ring, with a single gate, distinguishes the fourth subfamily of
Coronida, the Acanthodesmida (sensu restricto), the genera Coronidium (PI. 82,
figs. 1, 2, 7, 8) and Acanthodesmia (PL 93, fig. 5). The horizontal basal ring alone
is here complete, whilst both vertical rings (the sagittal and frontal rings) are incomplete,
their basal parts being wanting. Therefore there are here five gates, four lateral and one
basal. These forms may be derived from Eucoronis by loss of the basal rod of the
primary sagittal ring.

The Tympanida, the fourth family of S t e p h o id e a, exhibit another type of ring
structure. Here two parallel horizontal rings are constantly developed, one on the
apical pole, the other on the basal pole of the sagittal ring. The latter is the same
basal ring as in the Semantida and Coronida. The former is a " mitral ring," developed
in the same manner, by union of two pairs of horizontal lateral branches, which arise
on both sides from the apical rod (or mitral rod) of the sagittal ring. In the simplest
case these two parallel horizontal rings are connected only by the sagittal ring, which
is either complete (Protympanium, PL 93, fig. 14) or incomplete (Parastephanus,
PL 93, fig. 21). But commonly also an incomplete frontal ring is present, so that
the two horizontal rings are connected by four vertical or sub vertical rods ; two of
these " columellse " are the dorsal and ventral rods of the sagittal ring, the two others
are the lateral rods of the frontal ring. Between the former and the latter are
sometimes developed two, four, or more accessory columellse (probably halves of
accessory incomplete diagonal meridian rings). In this way arise the characteristic
" drum -forms " of many Tympanida, in which the two parallel horizontal rings
correspond to the upper .and lower rings of a drum, whilst the connecting vertical
columellse correspond to its parallel lateral rods (PL 83, figs. 1, 2, &c.).

Originally the two horizontal rings of these " drum-shells " are both bisected by
the complete sagittal ring, each provided with two lateral gates (Protympanida). But
in the Eutympanida both rings exhibit one simple gate only, the apical and the basal
rod of the sagittal ring being lost. In the Paratympanida both rings are closed by a
secondary lattice -plate, whilst in the Dystympanida the upper (mitral) ring alone is
closed by such a plate, the lower (basal) ring is open. In some Eutympanida the
shell assumes the .strange form of a regular geometrical cube, the twelve edges of which
are represented by thin rods of silex (Liihocubus) — its four upper edges represent
the mitral ring, the four lower the basal ring ; two opposite of the four vertical cube-

REPORT ON THE RADIOLARIA. 937

edges are the lateral halves of the frontal ring, the two other alternate ones are the
remaining halves of the reduced sagittal ring (dorsal and ventral rod) (PI. 82, fig. 12).

In many Tympanida and Coronida a loose irregular lattice or framework is
developed, which partly closes the large open gates. But this never reaches the com-
pleteness of a true lattice -shell, such as we find in the Spyroidea, Botryodea,
and C y r t o i d e a. In by far the greater number of Stephoidea the corners, and
partly also the rods, of the shell are armed with numerous irregular spines, often forked
or richly branched. Among these spines the descending " basal apophyses " possess
a peculiar importance, since by their regular number and disposition they correspond
to the radial rods of the Plectoidea, and to the typical " feet " of the Spyroidea
and Cyrtoidea. The most important of them are the three cortinar feet (one caudal
and two pectoral) of Cortina, Cortiniscus, &c. (compare above, p. 891).

The Central Capsule exhibits in the Stephoidea the same characteristic
structure as in all other MONOPYLEA, first exactly pointed out by Richard Hertwig in
1879 (Organismus der Radiol., p. 71, Taf. vii. figs. 4, 5). Its form is commonly ovate
or ellipsoidal, sometimes also lentelliptical or nearly spherical. It exhibits constantly
on the basal pole the porochora or porous area, and in the basal half the podoconus or
pseudopodial cone. From the surrounding sagittal ring it is separated by a thick
jelly-like calymma, which commonly exhibits numerous zooxanthellae. The numerous
pseudopodia are commonly branched, with rather rare anastomoses. The membrane of
the central capsule is thick.

Synopsis of the Families of Stephoidea.

I. Skeleton composed of the simple vertical sagittal ring only, without secondary

rings, . . . . . . . . .1. STEPHANIDA.

II. Skeleton composed of two crossed rings, a vertical sagittal and a horizontal basal

ring, ......... 2. SEMANTIDA.

III. Skeleton composed of two crossed vertical meridional rings (a primary sagittal

and a secondary frontal ring), commonly also with a horizontal basal ring, . 3. CORONIDA.

IV. Skeleton composed of two parallel horizontal rings (upper mitral and lower basal

ring), both connected by a vertical sagittal ring (and often by a vertical frontal

ring), . . . . . . . . .4. TYMPANIDA.

Family XLVIII. STEPHANIE A, Haeckel (PI. 81).

Monostephida, Haeckel, 1881, Prodromus, p. 447.

Definition. — S tephoidea with a simple sagittal ring, without any lattice -work.

The family Stephanidais the most simple of all Stephoidea, and probably
the common ancestral group of this suborder (compare above, p. 933). The skeleton

(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 118

938 THE VOYAGE OF H.M.S. CHALLENGER.

consists of a simple ring only, surrounding the central capsule, and armed commonly
with simple thorns or with larger branched spines. The branches of these spines are
constantly free, never joining together. Therefore the shell exhibits no trace of
fenestration or lattice-work, no pores or gates, except the simple large gate of the ring
itself. In all other Stephoidea we find secondary gates or lattice-work.

The first known form of this family is Lithocircus annularis, described by Johannes
Miiller in 1858 (Abhandl. d. k. Akad. d. Wiss. Berlin, p. 29, Taf. i. fig. 1). He
observed already the central capsule (" Blase ") surrounded by the circular ring of
silex, and the calymma (" Strahlige Gallert ") enveloping the whole body. The peculiar
structure of the soft body, particularly the " area porosa " on the basal pole of the
central capsule, and the pseudopodial cone within it, were first accurately described by
Hertwig (in 1879). A great number of simple rings, similar to these, were found in
the Challenger collection, and are here arranged in six genera and forty-eight species.

The simple ring of silex, which alone forms the skeleton of the Stephanida,
corresponds to the primary or sagittal ring of the other Stephoidea, and lies there-
fore vertically in the median or sagittal plane of the body. We can therefore
distinguish on it four different segments, rods or bows, two of which are more horizontal,
two more vertical. The former are one upper bow or apical rod, and one lower bow or
basal rod. The latter are one posterior bow or dorsal rod, and one anterior bow or
ventral rod. Sometimes each of these four component bows is distinguished by a
corner-spine, or by a pair of divergent branches.

In the two simplest (and probably oldest) genera of Stephanida, in Archicircus and
Lithocircus, the dorsal and ventral rods of the ring are equal and cannot be
distinguished ; therefore the fundamental form is here amphithect, diphragmatic, or
biradial (the poles of the sagittal axis being equal). In the four other genera the
dorsal rod is more straight (often vertical) and more or less different from the ventral,
convexly curved rod ; therefore the fundamental form is here dipleuric or bilateral, as
in the greater number of all NASSELLARIA (the poles of the sagittal axis being unequal).
The general form of the ring in this latter case is commonly obliquely ovate or
nearly triangular, the basal pole being more pointed, the apical pole more* rounded
(PI. 81).

The rods or bows of the ring are either roundish or cylindrical (with circular or
elliptical transverse section), or they are prismatic or angular (commonly with
triangular transverse section). In the latter case one edge usually is prominent in the
sagittal plane (on the convex outside of the ring), whilst two other edges diverge
laterally on both sides of it. The inner or concave margin of the ring is commonly
smooth.

The inner perimeter of the large gate, enclosed by the ring, is commonly rounded
(elliptical or ovate), rarely angular. However, the outer perimeter of the ring is

REPORT ON THE RADIOLARIA. 939

nearly always polygonal, with prominent corners, and usually from these arise thorns
or branched spines which are regularly disposed. Regarding this disposition we may
distinguish three cases : A, the spines lie in the sagittal plane and form a single row,
arising from the median edge ; B, the spines lie on both sides of the latter and form
two parallel rows, arising from the two lateral edges ; C, the spines represent a com-
bination of A and B, and are disposed in three rows, two paired rows arising from the
two lateral edges, and an odd middle row between them, arising from the median edge.
The spines are simple, without branches, in Archicircus and Zygocircus ; more or less
branched in Lithocircus and Dendrocircus. The branches are often richly ramified
or arborescent, and exhibit great variety in size, special form, and direction (compare
PL 81).

The number and disposition of the spines or groups of spines are usually constant,
and may be employed in the further progress of our knowledge, to distinguish a number of
genera and subgenera. Very commonly (perhaps in the majority of the Stephanida) we
find six groups of spines, an apical group on the upper rod of the sagittal ring, a basal
group on the lower rod (on the porochora of the central capsule), two ventral groups on
the anterior rod, and two dorsal groups on the posterior rod. In other species we find
four or eight groups instead of six, and sometimes a larger number.

The most important of these apophyses of the ring are the basal spines, arising
from its basal pole, where the porochora of the central capsule rests upon it.
They are often much larger and more branched than the other spines, and attain a
peculiar morphological value in the small subfamily Cortinida. Here we .find three
or four regularly disposed " basal spines," which may be compared to the typical " basal
feet " of the Cyrtellaria, appearing in the majority of Spyroidea and
Cyrtoidea. Cortina, one of the most important NASSELLARIA, bears three typical
divergent feet on the base of the simple ring, two paired anterior or " pectoral feet,"
and an odd posterior or " caudal foot." The latter appears as a direct basal prolonga-
tion of the dorsal rod of the ring, and is opposed to an upper prolongation of the same,
which corresponds to the "apical horn" of the Cyrtellaria (PI. 97, figs. 1—3).
As already explained above, these three basal feet of Cortina possess the highest phylo-
genetic value, since they may also be compared with the three primary radial spines of
the Plectoidea, and so connect the Cyrtellaria and the Fleet ella.ria.
Steplianium differs from Cortina in the possession of four basal feet, an odd anterior or
" sternal foot " being added to the three typical feet of the latter (PI. 92, figs. 20, 21).
Some forms of Plectoidea (Plagoniscus, Plectaniscus, &c.) seem to be nearly
related to these Cortinida, and may be easily transformed into them by development
of a complete ring, embracing the central capsule. They seem to demonstrate the near
affinity of all these triradiate NASSELLAKIA (PI. 91, figs. 4, 5, 9, 10).

940

THE VOYAGE OF H.M.S. CHALLENGES.

I. Subfamily

Lithocircida.

No typical basal feet on
the base of the ring (no
cortinar feet).

II. Subfamily

Cortinida.

Three or four typical basal
feet on the ring (cortinar
feet).

Synopsis of the Genera of Stephanida.

{Ring smooth or thorny, with-
out branched spines.
Ring armed with branched

(

spines,

I" Ring smooth or thorny, with-

Ring dipleuric, bilateral ; j out branched spines,
dorsal and ventral bow -j
different Ring armed with branched

[ spines.

Three basal feet (and an (
apical horn). |

One caudal and two lateral
feet,

Four basal feet (and an / Two sagittal and two lateral
apical horn). ( feet,

401.

402.

403.

404.

405.

406.

Arcliicircus.

Lithocircus.

Zygocircus.

Dendrocircus.

Cortina.

Stephanium.

Subfamily 1. LITHOCIRCIDA, Haeckel.
Definition. — S tephanida without typical basal feet or cortinar feet.

Genus 401. Archicircus,1 n. gen.

Definition. — S tephanida with a simple amphithect or diphragmatic ring, smooth
or thorny, without branched spines and basal feet.

The genus Archicircus is the most primitive and simplest form of all Stephoidea,
and probably the common ancestral form, not only of this suborder, but of the greater
number of all NASSELLARIA (compare above, p. 893). The skeleton consists only of a
quite simple sagittal ring, in which commonly a slight difference of both poles of the
main axis (basal and apical pole) is visible, but no difference between the dorsal and the
ventral bow of the ring. In my Prodromus (1881, p. 447) the species of Archicircus
were disposed partly in the subgenus Monostephus, partly in the genus Lithocircus.

Subgenus 1. Monostephus, Haeckel, 1881, Prodromus, p. 447.
Definition. — Ring circular, elliptical, or ovate, without prominent corners.

1 . Archicircus princeps, n. sp.

Gate circular. King circular, smooth, its transverse section also circular. The simplest form of
all Stephoidea.

Dimensions. — Diameter of the gate 0'05 to 0-08 ; thickness of the ring O'OOG to O'OOS.
Habitat. — Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

1 Archicircus = Primordial ring; ajjc'i *'j*of.

REPORT ON THE RADIOLARIA. 941

2. Archicircus monostephus, n. sp. (PI. 83, fig. 17).

Gate circular. Ring circular, with three elegantly denticulate edges (one outer median and
two lateral edges). Transverse section of the ring triangular.

Dimensions. — ^Diameter of the gate 0'06 to 0'08 ; thickness of the ring O'Ol to O'OOS.
Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Archicircus ellipsis, n. sp.

Gate elliptical. Eing elliptical, on the inner margin smooth, on the outer margin with fifteen
to twenty equal, short, simple, or slightly forked thorns. Transverse section ovate.

Dimensions. — Diameter of the gate 0'05 to 009; thickness of the ring O'Ol to 0'014
Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms ; also fossil in Barbados.

4. Archicircus ovalis, n. sp.

Gate ovate. Ring elliptical, smooth, with three prominent, slightly distorted edges, without
thorns ; in the transverse section triangular.

Dimensions. — Diameter of the gate 0'08 to 012 ; thickness of the ring 0'006 to 0'009.
Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

5. Archicircus monopylus, n. sp.

Gate ovate. Eing ovate, thorny, with three distorted edges, in the transverse section triangular ;
surface covered with numerous simple small thorns arising from the three edges.

Dimensions. — Diameter of the gate 01 to 015 ; thickness of the ring O'Ol to 0'012.
Habitat. — Indian Ocean (Madagascar), Eabbe, surface.

Subgenus 2. Archistephus, HaeckeL

Definition. — Ring polygonal, with four to six or more prominent corners (and
commonly with simple spines arising from the corners).

6. Archicircus quadratus, n. sp.

Gate square. Eing square, with three edges and four short simple pyramidal spines on the four
corners, opposite in pairs in two perpendicular diameters. Transverse section triangular.
Dimensions. — Diameter of the gate 0'08 ; thickness of the ring O'OOS.
Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

942 THE VOYAGE OF H.M.S. CHALLENGER.

7. Archicircus rhombus, n. sp. (PL 81, fig. 7).

Gate rhombic. Eing rhombic, with four prominent edges and four pairs of short, divergent,
pyramidal spines on the four corners, arising from the lateral edges of the four rods, about as long
as the radius of the gate.

Dimensions. — Diameter of the gate 0'04 to 0'08; thickness of the ring 0'007 to O'Ol.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

8. Archicircu^ duodenus, n. sp.

Gate square or rhombic. Eing rhombic, with three prominent edges and twelve stout and
straight pyramidal spines, about as long as the radius of the gate. In each of the four corners are
three divergent spines, arising from the three edges of each two meeting rods.

Dimensions. — Diameter of the gate 0'08 ; thickness of the ring 0'012.

Habitat. — North Atlantic, surface (Rabbe).

9. Archicircus primordialis, n. sp. (PI. 81, fig. 1).

Gate ovate. Eing hexagonal, with three prominent edges and six short pyramidal thorns at
the six corners ; the basal thorn is either simple or forked.

Dimensions. — Diameter of the gate 0'07 ; thickness of the ring O'Ol to 0'015.
Habitat. — Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

10. Archicircus hexacanthus, n. sp. (PL 81, fig. 4).

Gate subregular, hexagonal Eing hexagonal, with three sharp edges and six equal radial
pyramidal spines, arising from the six corners and placed in the plane of the ring, about as long
as the diameter of the gate.

Dimensions. — Diameter of the gate 0'05 to 0'07 ; thickness of the ring O'Ol.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

11. Archicircus hertivigii, Haeckel.

Lithotircus annularis, R. Hertwig (non J. Miiller), 1879, Organismus der Radiol., p. 69.
Taf. vii. fig. 5.

Gate hexagonal, with prolonged main axis. Eing hexagonal, with two prominent edges and
six pairs of equal, short, conical spines, arising from the two edges of the six rods at the six
corners and divergent on each side of the plane of the ring. The basal spine-pair is doubled,
therefore there are in all fourteen spines.

Dimensions. — Diameter of the gate 0'05 to 0'07 ; thickness of the ring O'OOo to O'OOG.

Habitat. — Mediterranean (Messina), Hertwig, surface.

REPORT ON THE RADIOLARIA. 943

12. Archicircus triglyphus, n. sp.

Gate ovate. Ring hexagonal, with three prominent edges and twenty-two to twenty-four
simple curved spines, arising from the six corners and about as long as the diameter of the gate.
In the basal corner arise six to nine larger spines, protecting the basal pole of the central capsule.
From each of the five other corners arise three spines, diverging from the three edges.

Dimensions. — Diameter of the gate 0'07 to Oil ; thickness of the ring O'OOS to O'Oll.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

13. Archicircus sexangularis, n. sp. (PL 81, fig. 12).

Gate hexagonal or subcircular. Ring hexagonal, with two sharp prominent edges and six pairs
of divergent spines, about as long as the radius of the gate, and arising from the two edges at the
six corners. The two apical and the two basal spines are simple and conical, whilst the eight
other spines, arising in pairs from the two dorsal and the two ventral corners, are slightly forked.

Dimensions. — Diameter of the gate 0'06 to 0'08 ; thickness of the ring O'Ol to 0'015.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 402. Lithocircus,1 J. Muller, 1856, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p.. 484.

Definition. — S tephanida with a simple amphithect or diphragmatic ring, armed
with branched spines, without typical basal feet.

The genus Lithocircus is the oldest known form of all S tephoidea, founded by
J. Miiller in 1856 for his Lithocircus annularis, the first species of this suborder
described. We retain here this cosmopolitan form as the typical representative of the
genus, which differs from the preceding Archicircus, its ancestral form, in the develop-
ment of branched radial spines.

1. Lithocircus annularis, J. Miiller.

Lithocircus annularis, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 29,
Taf. i. fig. 1.

Gate circular. Ring circular, with four forked or simply branched spines, opposite in pairs in
two diameters, perpendicular one to the other. Spines with slender curved fork-branches, about as
long as the diameter of the gate. The specimen figured by J. Miiller bears a supernumerary fifth
spine ; numerous other specimens observed by me exhibited a regular cross of four spines.

Dimensions. — Diameter of the gate 01 to 015; length of the spines O'Ol to 018.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, surface.

1 Lithocircus = Ring of silex ; x/do?,

944 THE VOYAGE OF H.M.S. CHALLENGER.

2. Lithocircus quadricornis, n. sp. (PI. 81, fig. 9).

Gate square. Eing square, with three sharp denticulate edges, and four large bunches of
richly branched spines on the four corners. In each corner arise three curved spines, about as
long as the diameter of the ring ; their numerous irregular branches are forked and curved like
the antlers of deer.

Dimensions. — Diameter of the gate 0'07 ; length of the horns 0'06 to 0'09.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

3. Lithocircus decimalis, n. sp. (PL 81, fig. 15).

Gate elliptical. Eing pentagonal, with three prominent edges and five pairs of branched spines
on the five corners. In each corner arise two or three curved spines, about as long as the radius
of the gate, each with two to four forked branches.

Dimensions. — Diameter of the gate 0'08 ; length of the spines 0'03 to 0'05.

Habitat. — North Atlantic, Station 354, surface.

4. Lithocircus hexdblastus, n. sp. (PL 81, fig. 17).

Gate elliptical. Eing hexagonal, with three prominent edges and six pairs of branched spines,
arising from the six corners. Each of the twelve spines is short and stout, only half as long as
the radius of the gate, and bears a bunch of ten to twenty short, densely aggregated, conical
or horn-like curved branches.

Dimensions. — Diameter of the gate 01 ; length of the spines 0'02 to 0'03.

Habitat, — Central Pacific, Stations 265 to. 268, depth 2700 to 2900 fathoms.

5. Lithocircus cratnbessa, n. sp. (PL 81, fig. 6).

Gate elliptical or subcircular. Eing hexagonal, with three wing-shaped distorted edges and six
groups of branched spines, arising from the six corners. In each corner arise three short and stout
divergent spines, each bearing a bunch of numerous short roundish branches like a cauliflower,
scarcely as long as the thickness of the ring.

Dimensions. — Diameter of the ring 01 to 012, length of the spines O'Ol to 0'02.

.Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

6. Lithocircus tarandus, n. sp. (PL 92, fig. 19).

Gate circular. Eing hexagonal, with three sharp edges and six pairs of large branched spines,
arising from the flat lateral edges on the six corners. Each of the twelve spines is horizontally
expanded, longer than the diameter of the ring and dichtomously forked like the antlers of a rein-

REPORT ON THE RADIOLARIA. 945

deer. If the lateral ends of the branches of this species become united in the frontal plane, we get
Microciibiis, the four upper spines forming the mitral ring, the four middle the equatorial ring, and
the four lower the basal ring.

Dimensions. — Diameter of the gate O08 ; length of the spines 0'09.

Habitat. — Central Pacific, Station 272, surface.

7. Lithocircus furcatus, n. sp.

Gate ovate. King ovate, with three sharp prominent edges. The two lateral edges are smooth,
The median edge (in the sagittal plane) bears sixteen to twenty forked spines (commonly eight
dorsal, eight ventral, and four basal). All the spines are of nearly equal size, slightly curved, and
about half as long as the short sagittal axis of the ring.

Dimensions. — Diameter of the gate 0'08 to 012 ; length of the spines 0'03 to 0'04

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

8. Lithocircus magnificus, n. sp. (PI. 81, fig. 16).

Gate ovate or nearly elliptical. King ovate, with three prominent edges, and numerous richly
branched spines arising from the three edges. The specimen figured, which I observed living in the
Mediterranean, exhibited eight bunches of larger spines, three dorsal, three ventral, one apical, and
one basal bunch ; the latter much larger than the seven others. Each bunch was composed of two
to four larger and numerous smaller spines, their branches curved and forked. The ovate purple
central capsule, with a distinct podoconus, filled more than the half of the gate.

Dimensions. — Diameter of the gate 01 to 013 ; length of the spines 0'05 to 015.

Habitat. — Mediterranean (Portofino, 1880), Atlantic (Canary Islands), Station 354, surface.

Genus 403. Zygocircus,1 Biitschli, 1882, Zeitschr. f. wiss. Zool.,, vol. xxxvi. p. 496,

Definition. — Stephanida with a simple dipleuric or bilateral ring, smooth or
thorny, without branched spines and basal feet.

The genus Zygocircus and the following Dendrocircus differ from the two preceding
older genera in the bilaterally symmetrical or dipleuric form of the sagittal ring. Whilst
in Archicircus and Lithocircus the two sagittal halves or bows of the ring, the dorsal
and ventral bow, are equal (therefore the fundamental form amphithect or diphrag-
matic), here both bows become distinctly different ; the dorsal bow is constantly more
straight (often vertical), the ventral bow more convex (obliquely ascending). This
dipleuric differentiation is most important, as it is transmitted to the greater number
of NASSELLABIA by heredity.

1 ZygocirciiA = Yoked or symmetrical ring ; £vyti>, x/jxoj.
(ZOOL. CHALL. EXP. — PAST XL. — 1886.) Rr 119

946 THE VOYAGE OF H.M.S. CHALLENGER.

1. Zygocircus sagittalis, n. sp.

Gate ovate. Ring half ovate or nearly triangular, with three curved edges and three prominent
corners, one apical and two basal protuberances. Dorsal rod vertical, twice as long as the horizontal
basal rod. Ventral rod convexly curved.

Dimensions. — Diameter of the gate 0'05 to O07 ; height of the tubercles O01 to 0'015.

Habitat. — Central Pacific, Stations 265 to 268, depth 2900 fathoms.

2. Zygocircus trigonus, n. sp.

Gate triangular. King triangular, with three curved edges and three prominent corners, which
are prolonged into nine divergent conical spines ; three spines arising from the three edges of each:
corner. Dorsal rod vertical ; ventral and basal rods curved and convergent.

Dimensions. — Diameter of the gate Oil to 013 ; length of the spines O'Ol to 0'015.

Habitat. — Indian Ocean, Sunda Archipelago (Eabbe), surface.

3. Zygocircus tetragonus, n. sp.

Gate ovate. King quadrangular, without edges, with four simple conical spines of different sizes ;
one smaller apical, one larger basal, and two equatorial spines of middle size (one dorsal and one
ventral). Dorsal and ventral rod curved.

Dimensions. — Diameter of the gate 0'04 to 0'06 ; length of the spines O'OIS to 0'026.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

4. Zygocircus rhombicus, n. sp.

Gate rhombic. King rhombic, with three prominent edges, and eight short conical curved
spines arising from the lateral edges at the four corners of the rhombus. The basal and ventral
spine are larger than the apical and dorsal spine ; the ventral rod is more curved (with smaller
angle) than the shorter dorsal rod. The medial edge of the ring is smooth, without spines.

Dimensions. — Diameter of the gate 0'08 ; length of spines 0'02 to 0'04.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

5. Zygocircus pentagonus, n. sp. (PL 81, fig. 8). •

Gate roundish pentagonal. King very thick (about as thick as the radius of the gate), irregularly
pentagonal, with prominent sagittal edge. On both sides of the latter arise at the five corners five
pairs of short simple irregularly curved spines. The four ventral spines are larger than the four
dorsal, and the two basal spines larger than the eight former, forked. (In fig. 8 the basal spines
are turned upwards.)

Dimensions. — Diameter of the gate O'O1? ; length of the spines 0'04 to 0'06.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

REPORT ON THE RADIOLARIA. 947

6. Zygocircus hexagonus, n. sp.

Gate irregularly hexagonal. Ring obliquely hexagonal, thick, without edges, with six short
and stout conical spines on the six corners. The two spines of the curved ventral rod are
longer than the two spines of the straight dorsal rod. The apical spine is smaller and the basal
spine larger than the four others.

Dimensions. — Diameter of the gate 0'07 to 0'09 ; length of the spines O'Ol to O03.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

7. Zygocircus triquetrus, n. sp. (PL 81, fig. 3).

Gate obliquely ovate. King obliquely hexagonal, with three sharp edges and three short conical
spines on each of the six corners. Therefore each hexagonal edge bears six short radial spines of
-equal size.

Dimensions. — Diameter of the gate 0'04 to 0'08 ; length of the spines O'Ol to 0'02.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific, surface.

8, Zygocircus dodecanthus, n. sp.

Gate semicircular. Eing semicircular or irregularly hexagonal, without edges, with twelve short
blunt spines, arising in pairs from the six corners ; two apical, two basal, and between them two
equatorial corners. Three pairs of spines remain on the straight dorsal rod, three on the curved
ventral rod.

Dimensions. — Diameter of the gate 0'04 to 0'06 ; length of the spines O'Ol to 0'02.

Habitat. — Central Pacific, Stations 263 to 268 ; depth 2650 to 2900 fathoms.

9. Zygocircus acacia, n. sp. (PI. 81, fig. 5).

Gate obliquely ovate. Eing semi-ovate, with straight dorsal and curved ventral rod, partly with
distorted edges. Six bunches of numerous short and straight conical spines arise from the ring, one
larger bunch (often trifid) from the apex, two smaller bunches from the dorsal, two from the
ventral rod, and one very large bunch from the base. The six bunches are often more separated,
smaller, and the spines shorter than in the figured specimen, which passes over into Dendrocircus.

Dimensions. — Diameter of the gate 012 to 016 ; length of the spines, O'Ol to 0'07.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

10. Zygocircus polygonus, n. sp. (PL 81, fig. 2).

Gate irregularly roundish or ovate. Eing irregularly polygonal or sometimes nearly circular,
without edges, armed with a single series of ten to fifteen short pyramidal spines, which are irregularly

948 THE VOYAGE OF H.M.S. CHALLENGER.

disposed in the sagittal plane. The ventral rod is strongly curved, often semicircular, the dorsal
rod less curved or nearly straight.

Dimensions. — Diameter of the gate 0'05 to O07 ; length of the spines 0'004 to 0'02.

Habitat. — Cosmopolitan — Atlantic, Pacific ; also fossil in Barbados.

11. Zygocircus biitschlii, n. sp.

Zygocircus produdus, Biitschli, 1882, Zeitsehr. f. wiss. Zool., vol. xxxvi. p. 497.

Grate obliquely ovate. King irregularly roundish, semi-ovate or ovate, with interrupted and
distorted edges, and with a large number (ten to twenty or more) of simple, irregularly formed and
asymmetrically disposed spines ; commonly some larger spines at the base.

Dimensions. — Diameter of the gate 0'05 to 0'09 ; length of the spines O'OOS to 0'02.

Habitat. — Fossil in Barbados.

12. Zygocircus productus, Biitschli.

Zygocircus productus, Biitschli, 1882, Zeitsehr. f. wiss. Zoo]., vol. xxxvi. p. 496.
Lithoeircus productus, R. Hertwig, 1879, Organismus d. Radiol., p. 69, Taf. vii. fig. 4.

Gate obliquely ovate. Eing obliquely ovate, with three complete prominent edges and with
numerous (ten to twenty or more) simple, short conical spines, arising in three series from the three
edges ; commonly some smaller spines at the base.

Dimensions. — Diameter of the gate 01 to 0'2 ; length of the spines 0'005 to 0'02.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific, surface.

Genus 404. Dendrocircus,1 Haeckel, 1881, Prodromus, p. 447.

Definition. — S tephanida with a simple dipleuric or bilateral ring, armed with
branched spines, without typical basal feet.

The genus Dendrocircus has the same dipleuric or bilaterally symmetrical form of
the sagittal ring as its ancestral genus Zygocircus. It differs from the latter in the
development of branched radial spines, and therefore bears to it the same relation as
the amphithect Lithoeircus does to the simpler Archicircus.

1. Dendrocircus quadrangulus, n. sp.

Gate irregularly quadrangular or nearly semicircular. Ring quadrangular, edgeless, with four
unequal sides ; ventral rod more curved and with longer sides than the dorsal rod. From the
four edges arise four strong, irregularly branched spines, about as long as the diameter of the gate,

1 De7idroaYctts=Ring bearing trees ; 8si/8jo», xloxo;.

REPORT ON THE RADIOLARTA. 949

with curved branches; the ventral and basal spines larger than the dorsal and apical spines.
Similar to Lithocircus quadricornis (PI. 81, fig. 9), but less branched, and with a striking difference
between the shorter dorsal and the longer ventral rod.

Dimensions. — Diameter of the gate 0-04 to 0'06 ; length of the spines O05 to 0'07.

Habitat. — North Pacific, Station 256, depth 2950 fathoms.

2. Dendrocircus dodecarrhiza, n. sp.

Gate obliquely ovate. Ring irregularly quadrangular, with three prominent edges. From the
latter arise at the four corners twelve divergent, irregularly branched spines (three in each corner),
about as long as the radius of the gate, with curved branches ; the three basal spines larger than
the nine others.

Dimensions. — Diameter of the gate 0'08 to 01 ; length of the spines 0'04 to 0'06.

Habitat. — Indian Ocean (Maldive Islands), surface (Haeckel).

3. Dendrocircus dodecancistra, n. sp. (PI. 81, fig. 11).

Gate obliquely ovate or nearly elliptical. Ring irregularly ovate, with three distorted edges and
six pairs of branched spines. The two ventral pairs are much more distant than the two dorsal
pairs, the ventral rod being longer and more curved than the dorsal rod. All twelve spines are of
nearly equal size, are more or less curved, about as long as the diameter of the gate, and each bears
six to twelve irregular short branches at the end.

Dimensions. — Diameter of the gate 0'07 to 0'08 ; length of the spines O05 to 0'08.

Habitat. — Tropical Atlantic, Station 342, depth 1445 fathoms.

4. Dendrocircus arborescens, n. sp. (PL 81, fig. 10).

Gate irregularly roundish or nearly circular. Ring of the same form, with slight edges and" six
pairs of elegant arborescent spines (one apical, two dorsal, two ventral, and one basal pair) ; the
three latter somewhat larger than the three former. Each tree is larger than the ring, in the basal
half simple, in the distal half forked, each fork-branch with numerous dichotomous terminal
branches.

Dimensions. — Diameter of the gate 0'06 to 0'08 ; length of the spines 012 to 015.

Habitat. — Central Pacific, Stations 266 to 274, surface.

5. Dendrocircus elegans, n. sp. (PI. 81, fig. 13)-

Gate irregularly ovate. Ring thick, ovate, with three denticulate edges and six bunches of stout,
branched and spinulate, curved spines. The four ventral spines are more distant than the four
dorsal, the ventral rod being more curved than the dorsal The latter bears above the two apical
spines. The two basal spines are much larger, deeply forked ; their four fork-branches may be
compared to the four basal feet of Stephanium.

Dimensions. — Diameter of the ring 0'09 to Oil; length of the spines 0'03 to 0'06.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

950 THE VOYAGE OF H.M.S. CHALLENGER.

6. Dendrocircus barbadensis, n. sp.

Gate irregularly ovate or nearly semicircular. King of the same oblique form, thick, with
interrupted and distorted edges, armed with eight to twelve larger irregularly formed and branched
acute spines ; between them numerous conical smaller spines. This common species is very
polymorphous and variable.

Dimensions. — Diameter of the ring 0'05 to 0'08 ; length of the spines O'OOS to 0'02.

Habitat. — Fossil in Barbados.

7. Dendrocircus stalactites, n. sp. (PL 81, fig. 14).

Gate obliquely ovate. King irregularly ovate or roundish, very thick, without edges, armed with
numerous (eight to twelve or more) short and stout branches, which are shorter than the diameter
of the gate, irregularly disposed and branched, with very numerous clustered blunt ramules.

Dimensions. — Diameter of the gate 0'07 to 0'09 ; length of the spines 0'02 to 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 44*75 fathoms.

Subfamily 2. CORTINIDA, Haeckel.
Definition. — S tephanida with typical basal feet (or cortinar feet).-

Genus 405. Cortina,1 n. gen.

Definition, — S tephanida with a simple dipleuric or bilateral ring, bearing at
the base three divergent feet (one odd caudal and two paired lateral feet).

The genus Cortina, and the following Stcphanium represent together the small but
very important group of Cortinida, differing from the simple Lithocircida in the
possession of three typical basal feet, which are transmitted to the majority of the
NASSELLARIA by heredity, and produce their peculiar triradial structure. They appear
therefore as a combination of the simple ring (Zygocircus) with three basal feet
(Plagonium). One of these three divergent feet is the odd caudal foot, opposite
to the apical horn ; the two others are the paired lateral or pectoral feet. (On the
probable origin and the typical signification of Cortina compare above, pp. 891—894.)

.1.- Cortina tripus, n. sp. (PI. 83, fig. 9).

.King ovate, smooth, or with a few short thorns. Apical horn oblique, curved, simple, smooth,
about as long as the sagittal axis of the ring. Feet divergent, curved, simple, smooth, about as

1 Cortina = Tripod.

REPORT ON THE RADTOLARIA. 951

long as the horn ; the caudal foot shorter than the two pectoral feet Very variable in form and
size.

Dimensions. — Height of the ring 0'06 to 0'09, breadth 0'04 to 0'06 ; length of the feet 0'05
to 01.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, surface and in various depths.

2. Cortina typus, n. sp. (PI. 97, fig. 1).

Eing kidney-shaped or nearly semicircular, with revolute vertical dorsal rod and strongly
curved ventral rod ; both rods with two pairs of spine-bunches. Apical horn nearly straight,
thorny, longer than the ring, directed a little obliquely backwards. Feet slightly curved, of equal
length, two .to three times as long as the ring ; each armed with few large bunches of curved spines,
which are more developed in the caudal foot than in the two pectoral feet.

Dimensions. — Height of the ring 014, breadth 0'08 ; length of the feet 0'2 to 0;3>

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

3. Cortina conifera, n. sp.

Eing subcircular, smooth. Apical horn and the three divergent feet of equal size and similar
form, cylindrical, straight, about as long as the ring, at the distal end thickened, with a dimply cone
(similar to Tripospyris conifera and Tripospyris eucolpa, PL 84, figs. 4, 7).

Dimensions. — Height of the ring 0'08, breadth 0'06 ; length of the feet 0'09.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

4. Cortina furcata, n. sp.

Eing elliptical, with three forked horizontal spines (one on the dorsal and two on the ventral
rod). Apical horn and the three divergent feet of equal size, somewhat longer than the ring,
slightly curved, in the distal half forked.

Dimensions. — Height of the ring 0'07, breadth 0-05 ; length of the feet O'OQ.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

5. Cortina dendroides, n. sp.

Eing ovate, with six pairs of branched horizontal spines, three on the dorsal and three on the
ventral rod. Apical horn very large, arborescent, about as long and as broad as the ring. Feet
similar to the horn, also richly branched, of equal size. All the rods and their branches curved, with
prominent distorted edges.

Dimensions. — Height of the ring 013 to 017, breadth 01 to 012; length of the feet 01'5
to 0-2.

Habitat. — Central Pacific, Stations 266 to 274, depth 2350 to 2925 fathoms.

952 THE VOYAGE OF H.M.S. CHALLENGES.

6. Cortina cervina, n. sp. (PI. 92, fig. 21).

Eing ovate, with four pairs of forked horizontal spines (two dorsal and two ventral pairs)
Apical horn straight and stout, as long as the ring, with trifid point. Three feet equal,
widely divergent, very large, branched like a deer's antler, with very numerous short and stout,
curved and pointed branches. All rods and branches roundish, without edges.

Dimensions. — Height of the ring 01, breadth 0'07 ; length of the feet 012 to 016.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Genus 406. Stephanium,1 n. gen.

Definition. — S tephanida with a simple dipleuric or bilateral ring, bearing at
the base four divergent feet (two sagittal and two lateral feet).

The genus Stephanium differs from the preceding nearly allied Cortina in the
production of four basal feet ; the new foot, missing in the latter, is the anterior or
sternal foot. Therefore Stephanium may be regarded as the archetype of all those
NASSELLARIA in which, on the base of the sagittal ring, there are developed four typical
feet — two sagittal feet (the posterior caudal and anterior sternal foot) and two lateral
feet (right and left). On the origin of Stephanium compare above, p. 893, &c.

1. Stephanium quadrupes, n. sp. (PI. 92, fig. 20).

Ring ovate, with three prominent dentate edges and a short pyramidal apical horn. Four feet
all of nearly equal size, about as long as the ring, also with three thorny edges, in the upper half
divergent, in the lower convergent.

Dimensions. — Height of the ring 012, breadth 0'08 ; length of the feet Oil to 013.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Stephanium tetrapus, n. sp.

Ring elliptical, without edges, thorny, with a stout, thorny apical horn of the same length.
Four feet curved and irregularly branched, divergent, of different size. The two sagittal feet (the
anterior sternal and posterior caudal) about as long as the ring. The two lateral feet (right and
left) nearly twice as long, more richly branched.

Dimensions. — Height of the ring 016, breadth Oil ; length of the feet 015 to 0'3.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

1 Stephanium= Small crown or garland ; att<fa.tiiiiv.

REPORT ON THE RADIOLARIA. 953

Family XLIX. SEMANTIDA, n. fam.

Definition. — S tephoidea with a single vertical ring (the primary sagittal ring),
bearing on its base a horizontal ring (basal or cortinar ring) with two to four or
more basal gates (or cortinar pores).

The family Semantida differs from the preceding Stephanida in the development
of a small horizontal ring oh the base of the primary vertical sagittal ring. By the
crossing of these two rings a small latticed basal plate is formed, with one or two pairs
of pores ; rarely with a greater number of " basal pores." The production of this
characteristic " basal plate " is of the greatest morphological importance, as the
beginning of the numerous different lattice-formations, which are differentiated in the
great majority of NASSELLARIA.

In my Prodromus (1881, p. 446) I had enumerated the Semantida with three
genera (Nos. 298 to 300) as a separate subfamily of the Dyostephida or " Stephoidea
biannularia," and characterised these " Dyostephanida " by the following definition :
" Skeleto annulis duobus composite, qui in duobus planis invicem perpendicularibus
jacent ; altero annulo (sagittali) verticali, altero (basali) horizontali." As the names
there given were already employed with another signification, and as the Zygostephanida
(there united with the Dyostephanida) are more closely related to the Coronida, I
now change the names, and propose to call the family Semantida, expressing by this
term the typical similarity of the skeleton to a signet-ring (Semantis, Semantrum,
Semantidium).

At about the same time, some Stephoidea of this family were accurately
described by Biitschli (1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 495, Taf. xxxii.
figs. 6, 7, 8). He called them Stephanolithis, a name which Ehrenberg had em-
ployed, not for complete shells of Kadiolaria, but for isolated parts of such, and for
siliceous fragments of different skeletons, needles of Sponges, &c. The three species
described by Biitschli represent three different genera of our Semantida, viz., Semantis
spinescens (with two gates in the basal plate), Semantrum mulleri (with four gates),
and Semokntidium haeckelii (with six gates). He pointed out the great morpho-
logical value of the fenestrated basal plate and its paired gates, as beginnings of
numerous other NASSELLARIA. But his opinion, that in all S p y r o i d e a and C y r-
t o i d e a, derived from these, two pairs of basal gates were constant, was erroneous,
nor was the formation of the first pair naturally explained ; he supposed that the
formation of the basal plate begins by development of an odd sagittal apophysis,
arising from the base of the primary sagittal ring. But this odd sagittal apophysis
(" der unpaare mediane Kieselfortsatz cl", loc. cit., p. 497) is in reality not a primary

(ZOOL. CHALL. BXP. — PART XL. — 1886.) Hi1 120

954 THE VOYAGE OF H.M.S. CHALLENGER.

and essential part of the skeleton, but secondary and of little morphological value,
absent in the majority of the Semantida and of the other NASSELLARIA.

We divide our family Semantida into two different subfamilies, which possibly
possess a direct phylogenetic relation to the two subfamilies of Stephauida : — The
Semantiscida have no typical feet, and have arisen directly from the Lithocircida ; the
Cortiniscida, however, possess the three typical basal feet of Cortina, and may there-
fore be derived directly from the Cortinida. Since these three cortinar feet are
probably identical with the three primary radial rods of the Plectoidea, an imme-
diate affinity also to these NASSELLARIA is indicated.

The Semantiscida, which do not possess these three basal cortinar feet, are the simpler
forms of the family. The simplest of all, and perhaps the common ancestral form of
the whole family, is Semantis (PI. 92, figs. 1, 2). It may be derived from Archicircus
or Zygocircus by development of two pairs of horizontal apophyses on its base, around
the porochora of the central capsule. The two rods of each side (right and left),
becoming curved one towards the other, and meeting laterally, form a simple horizontal
gate, and the two paired basal gates together, a horizontal ring or basal ring, to which
the primary sagittal ring is perpendicular. In the next allied genus, Semantrum (PL
92, figs. 3—5), three pairs of horizontal apophyses are developed, and therefore two
pairs of basal gates produced, an anterior and a posterior. In the third genus,
Semantidium (PL 92, figs. 6, 7), three pairs of basal pores or gates are visible,
surrounded and separated by four pairs of horizontal apophyses, which arise from the
base of the sagittal ring. Finally, in Clathrocircus (PL 92, figs. 8—10) the number
of apophyses is much increased, and two parallel rows of pores are developed along the
two sides of the sagittal ring.

The basal plate or the "seal," developed from the base of the primary sagittal ring
or " signet-ring," is therefore a horizontal ring, which becomes bisected by the latter,
and exhibits either one pair of primary " basal gates " or two or three pairs of
these important basal pores, rarely more. Since these pores possess the greatest
morphological value, and are probably everywhere homologous, we give to them and to
the separating apophyses certain names, and call the anterior pair of gates, "jugular
pores " (i in our figures, the pair I of Biitschli) ; the middle (usually the largest) pair,
" cardinal pores " {& in our figures, the pair II of Biitschli), and the posterior, smaller
pair, " cervical pores," I. The typical pairs of rods, by the union of which these basal
pores arise, are the following : — (1) the clavicular or furcular rods,/, the first pair (rods
el of Biitschli), (2) the coracal rods, e, between the jugular and cardinal pores (rods
e of Biitschli), (3) the scapular rods, g, between the cardinal and cervical pores (rods
e2 of Biitschli), (4) the cervical rods, the fourth pair of apophyses, the most posterior, h.
Biitschli supposes that the topographical succession of the three typical pairs of
basal pores is also the chronological succession, the jugular being formed first, the

KEPORT ON THE RA.DIOLARIA. 955

cardinal second, and the cervical pores third ; but it seems that this succession is
often altered, and that the cardinal pores (the largest), appear first, the jugular pores
(in front of them) second, and the cervical pores third (or perhaps sometimes in the
inverse succession).

The Cortiniscida, the second subfamily of Semantida, differ from the preceding
Semantiscida in the possession of three typical basal feet, which are probably inherited
from the Cortinida, and perhaps indirectly from the Plagonida (Plagoniscus). The
simplest and the most important form of this second family is Cortiniscus (PI. 92, figs.
11—13), differing from its probable ancestral form, Cortina, in the development of a
basal ring, produced by horizontal union of the basal apophyses. The three typical
feet are the same as in all triradiate NASSELLARIA, two paired pectoral feet (p^, _pn)
diverging on the anterior base of the sagittal ring, whilst the odd caudal foot (c) lies on
its posterior base in the sagittal plane and appears as a basal prolongation of the dorsal
rod of the sagittal ring ; the upper part of the dorsal rod is usually prolonged into an
ascending apical horn. In Stephaniscus (PI. 92, figs. 14, 15) four basal feet are
visible, an anterior or sternal foot (z) being added as a prolongation of the basal rod of
the ring, opposite to the caudal foot. Finally, Semantiscus (PL 92, figs. 16—18) is
distinguished by the possession of six divergent basal feet, probably identical with those
of all six-radiate NASSELLARIA ; three of these may be regarded as primary and per-
radial, the odd caudal and the paired pectoral feet; the three other intercalated as
secondary or interradial feet, the odd sternal (z) and the paired tergal feet (^, tn).

The basal plate of these Cortiniscida exhibits the same important differences as in the
preceding Semantiscida, either one, or two, or three pairs of basal gates being developed.
But there occur also in some species (mainly in Cortiniscus) only three basal gates, an
odd anterior (between the two pectoral feet and a connecting horizontal bar), and two
paired posterior (between the two pectoral and the odd caudal foot). It requires further
accurate researches to solve the important problem, what the true homologies of these
typical basal pores and the separating bars are in the different genera of Semantida.
In Semantiscus there are three pairs of basal pores in the horizontal seal, correspond-
ing to those of Semantidium, and the radial rods or bars between these are the basal parts
of the six radial feet ; therefore the odd caudal foot (t) seems to be the posterior, and
the odd sternal foot (z) the anterior prolongation of the basal part of the primary
sagittal ring; the two paired anterior or pectoral feet (jov pn) the prolongations of
the coracal rods (e) and the two paired posterior or tergal feet (tlt <n), the prolongations
of the scapular rods (g). But it is not yet certain whether these six radial feet and
the separating gates of the basal plate are all the same and truly homologous in all six-
radiate NASSELLARIA. In every case the comparative study of the Semantida is of
the highest value for the accurate knowledge of the MONOPYLEA.

956

THE VOYAGE OF H.M.S. CHALLENGER.

I. Subfamily

Semantiscida.

Basal ring without typical,
regularly disposed basal
feet (no cortinar feet).

II. Subfamily

Cortiniscida.

Basal ring with typical,
regularly disposed basal
feet (cortinar feet).

Synopsis of the Genera of Semantida.

{Two basal pores, .
Four basal pores, .
Six basal pores,

Besides four basal pores, also apical pores or dorsal and
ventral pores along the whole ring,

Three basal feet.

Four basal feet.

Six basal feet.

One odd caudal foot and
two paired lateral feet, .

f Two sagittal and two lateral

I or pectoral feet,

f Two sagittal, two pectoral,

( and two tergal feet,

407. Semantis.

408. Semantrum.

409. Semantidium.

410. ClatJirocircus.

411. Gortiniscus.

412. Stephaniscits.

413. Semantiscus.

Subfamily 1. SEMANTISCIDA, Haeckel.
Definition. — S emantida without typical basal feet or cortinar feet.

Genus 407. Semantis,^ n. gen.

Definition. — S emantida with two basal pores (or jugular pores), without
typical basal feet.

The genus Semantis, the most primitive and the oldest of the Semantida, is of the
greatest morphological interest, as the first form of Stephoidea which produces
gates or pores by communicating branches, and therefore the probable ancestral form not
only of this family, but of the greater number of all Stephoidea, and perhaps even
of all Spyroidea and Cyrtoidea. Semantis arises from Archicircus by the pro-
duction of two pairs of lateral branches from the basilar rod of the sagittal ring, one
anterior pair of clavicular rods, and one posterior pair of coracal rods. By junction of the
clavicular and coracal rod on each side arises a left and a right pore, the "jugular pore or
jugular gate."

1. Semantis biforis, n. sp. (PI. 92, fig. 2).

Sagittal ring obliquely ovate, nearly trapezoidal, with six pairs of short marnmillated knots or
branches ; dorsal rod straight, vertical, with two pairs of knobs, ventral rod strongly convex, also with

1 Semantis = Signet-ring ;

EEPORT ON THE RADIOLARIA. 957

two pairs of knobs ; two other pairs in the apical rod. Basilar rod horizontal, straight. Basal
ring with six pairs of similar knobs, three on each side. Basal gates ovate or nearly triangular.

Dimensions. — Height of the sagittal ring O09, breadth 0'07.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

2. Semantis distoma, n. sp.

Sagittal and basal ring nearly of the same form as in the preceding species, but half as thick
and armed with numerous branched spines which are about half as long as the diameter of the
main gate, and with thin and curved pointed branches.

Dimensions. — Height of the sagittal ring O'll, breadth 0'08.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

3. Semantis dipyla, n. sp.

Sagittal ring kidney-shaped, very thick, with six pairs of short, thorny, or irregularly
tuberculated knobs (two dorsal, two apical, and two ventral pairs). Basal ring smooth, scarcely
half as thick, horizontal, with two semicircular basal gates, about half as broad as the main gate.
From the two opposite lateral corners of the basal ring two slender upwardly curved spines arise,
resembling the basal part of a commencing frontal ring.

Dimensions. — Height of the sagittal ring 0'08, breadth 0'05.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

4. Semantis sigillum, n. sp. (PI. 92, fig. 1).

Sagittal ring elliptical, with four pairs of stout arborescent spines (two apical and two
equatorial pairs), which are irregularly branched and forked, with numerous thin lateral branches.
Apex with a short conical trifid vertical horn. Basal ring thorny, with obliquely descending slightly
curved bars.

Dimensions. — Height of the sagittal ring 012, breadth 0'09.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

5. Semantis distephanus, n. sp. (PL 83, fig. 3).

Sagittal ring thin, semicircular, smaller than the thin basal ring, which exhibits two semi-
circular gates. Both rings are armed with numerous small spines of equal size, which on the
former are arranged in two, on the latter in three regular rows. (The basal rod of the sagittal ring,
separating the two basal gates, in fig. 3 is, by mistake, not distinctly enough drawn.)

Dimensions. — Height of the sagittal ring 0'06, breadth 0'08.

Habitat. — Tropical Atlantic, Station 348, surface.

958 THE VOYAGE OF H.M.S. CHALLENGER.

6. Semantis spinescens, Haeckel.

StepTianolithis spinescens, Elirenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 160, Taf.

i. fig. 29.
StepUanolithis spinescens, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 497, Taf. xxxii.

figs, la, 76.

Sagittal ring ovate, with four pairs of thin, irregularly branched spines, two apical pairs, one
on the straight dorsal rod, and one on the curved ventral rod. Basilar rod with a posterior and
an anterior forked rod (commencing caudal and sternal foot). Basal ring square, with two lateral
spines, and .two triangular gates scarcely one-third as broad as the ring-gate. An internal ascend-
ing procolumna (rod q in the figure of Biitschli) connects the basal and ventral rods of the
sagittal ring.

Dimensions. — Height of the sagittal ring 01, breadth 0'07.

Habitat. — Fossil in Barbados.

Genus 408. Semantrum,1 n. gen.

Definition. — S emantida with four basal pores (two anterior jugular and two
posterior cardinal pores), without typical basal feet.

The genus Semantrum, one of' the most important of the NASSELLARIA, arises from
the preceding Semantis by duplication of the two basal gates. Behind the pair of
coracal rods there arises from the basilar rod of the sagittal ring a third pair of lateral
horizontal branches, the scapular rods. These become connected with the coracal rods
on each side, and so produce a second posterior pair of basal pores, the " cardinal
gates." These are constantly larger than the anterior "jugular gates." Therefore the
vertical ring of Semantrum possesses a horizontal basal ring with four very characteristic
gates, enclosed by three pairs of lateral curved and connected branches, and these
become transmitted by heredity to the majority of the NASSELLAKIA.

1. Semantrum quadrifore, n. sp. (PI. 92, fig. 5).

Sagittal ring subcircular or ovate, with three edges and four sagittal forked spines on the odd
edge (two dorsal and two ventral spines). Basal ring decagonal, with ten simple or forked spines
on the ten corners. Jugular gates tetragonal. Cardinal gates pentagonal.

Dimensions. — Height of the sagittal ring 009, breadth 0'07.

Habitat. — Tropical Atlantic, Station 351, surface.

1 Semantrum= Signet-ring ;

REPORT ON THE RADIOLARIA. 959

2. Semantrum tetrastoma, n. sp. (PI. 92, fig. 3).

Sagittal ring semicircular, thorny, without edges. Basal ring tetragonal or nearly cordate,
with a small anterior and a large posterior bow-shaped incision ; on the lateral edges with numerous
irregular thorns. Jugular gates pear-shaped. Cardinal gates nearly kidney-shaped.

Dimensions. — Height of the sagittal ring O'l to 0'14, breadth 0'07 to 0'09.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

3. Semantrum tetrapylum, n. sp.

Sagittal ring elliptical, tuberculate. Basal ring trapezoidal, also with roundish thick rods and
small irregular tubercles on the margin. Jugular gates ovate, two-thirds as broad as the triangular
cardinal gates.

Dimensions. — Height of the sagittal ring O'OS, breadth O'Oo.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

4. Semantrum mulleri, Haeckel.

Stephanolithis mulleri, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. pp. 499, 539,
Taf. xxxii. figs. 8a, 8b, So.

Sagittal ring nearly semicircular or obliquely ovate, thorny. Basal ring also nearly semicircular,
with two slight sagittal incisions (one anterior and one posterior), on the lateral edges with
numerous small thorns. Jugular pores (pair I of Biitschli) pear-shaped. Cardinal pores (pair IT.
of Biitschli) triangular. Sometimes (but not constantly) a pair of cervical bows connects the
scapular bars with the subvertical dorsal rod of the sagittal ring.

Dimensions. — Height of the sagittal ring 0-09, breadth 0'06.

Habitat. — Fossil in Barbados.

5. Semantrum sphragisma, n. sp.

Sagittal ring circular, smooth. Basal ring also nearly circular and smooth ; its four basal gates
of nearly equal size, elliptical or subcircular ; the jugular pores scarcely smaller than the cardinal
pores. All rods smooth, cylindrical, without edges and thorns.

Dimensions. — Height of the sagittal ring O'OS, breadth 0'07.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms ; also fossil in Barbados.

G. Semantrum biitschlii, n. sp.

Sagittal ring triangular, with vertical straight ascending dorsal rod, horizontal straight basilar rod
and obliquely ascending, slightly curved ventral rod ; all rods nearly cylindrical, with irregular

960 THE VOYAGE OF H.M.S. CHALLENGER.

branched thorns and distorted edges. Jugular pores triangular, scarcely half as broad as the large
semicircular cardinal pores.

Dimensions. — Height of the sagittal ring Oil, breadth 0'08.

Habitat. — Fossil in Barbados.

7. Semantrum signarium, n. sp. (PL 92, fig. 4).

Sagittal ring obliquely ovate, thorny. Basal ring kidney-shaped or nearly pentagonal, with
broad concave dorsal incision and five larger branched spines on the five corners ; between them
smaller thorns. Jugular gates pear-shaped, scarcely half as broad as the triangular cardinal gates.

Dimensions. — Height of the sagittal ring 012, breadth OD9.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 409. Semantidium, n. gen.

Definition. — S emantida with six basal pores (two anterior jugular, two middle
cardinal, and two posterior cervical pores), without typical basal feet.

The genus Semantidium exhibits a further developmental stage of the basal plate of
the Semantida. Whilst this plate in Semantis possesses one pair of basal pores, and
in Semantrum two pairs, here in Semantidium it has three pairs. The new third
pair is produced on the dorsal edge of the basal plate, which becomes connected with
the basal part of the dorsal rod of the sagittal ring by a pair of cervical rods. The
middle pair of pores (the cardinal) are always larger than the anterior (jugular) and
the posterior (cervical pores). The same form of basal plate is preserved in numerous
Spyroidea and C y r t o i d e a, as .a " cortinar septum with six collar pores," (e.g.,
PI. 53, fig. 18).

1. Semantidium hexastoma, n. sp. (PI. 92, fig. 6).

Sagittal ring ovate, thorny. Basal ring rhombic or nearly square, with four short conical
descending spines on the four prominent edges (two sagittal and two lateral) ; between them
numerous smaller irregular thorns. Jugular and cervical gates nearly equal, ovate, half as broad
as the triangular cardinal gates between them.

Dimensions. — Height of the sagittal ring 014, breadth 01.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Semantidium sexangulum, n. sp.

Sagittal ring ovate, with six pairs of short branched thorns (two apical, two dorsal, and two
ventral). Basal ring hexagonal, with three pairs of short branched thorns on the six corners (one

1 Semantidium= Small signet-ring; v(itu.a.niti<nt.

REPORT ON THE RADIOLARIA. 961

sagittal pair, one posterior and one anterior). All six gates of the basal plate triangular, the
jugular and cervical a little smaller than the cardinal gates.

Dimensions. — Height of the sagittal ring O'l, breadth 0'07.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

3. Semantidium haeckelii, Biitschli.

Stephanolithis Haeckelii, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. pp. 499, 538, Taf.
xxxii. figs. 6a, 6ft.

Sagittal ring elliptical, with three pairs of short horizontal branched spines, one apical and two
equatorial pairs (one dorsal and one ventral). Basal ring roundish hexagonal, with numerous short
thorns on the margin. Jugular pores ovate, about half as broad as the ovate cardinal pores and
twice as broad as the small cervical pores.

Dimensions. — Height of the sagittal ring 0'08, breadth 0'06.

Habitat. — Fossil in Barbados.

4. Semantidium signatorium, n. sp. (PI. 92, fig. 7).

Sagittal ring semicircular, thorny ; basal ring pentagonal, with short spines on the margin and
five stronger thorny spines on the five corners. Jugular pores ovate, smaller than the triangular
cervical pores. Cardinal pores two to three times as large as each of the former, pentagonal.

Dimensions. — Height of the sagittal ring 0'08, breadth 0'12.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

Genus 410. Clathrocircus,^ Haeckel, 1881, Prodromus, p. 447.

Definition. — Semantida with a variable number of pores on the apical and the
basal part of the ring, symmetrically arranged, without typical basal feet.

The genus Clathrocircus comprises those Semantida in which the sagittal ring
bears not only basal pores (as in the three preceding genera) but also apical pores (on
the opposite pole of the main axis), or a variable number of pores along the whole
ring. All these pores are symmetrically arranged in pairs. In the simplest form there
are only two apical pores opposite to four basal pores, whilst in the highest state
of development the whole ring bears two complete circles of pores. At both poles of
the transverse axis two large lateral gates remain open. If these become closed by
lattice-work, Clathrocircus passes over into Dictyospyris.

1 Clathrocircus — Lattice-ring; xx»jfy>(», KI'^KO;.

(ZOOL. CHALL. EXP. — PABT XL. 1886.) Rr 121

962 THE VOYAGE OF H.M.S. CHALLENGER.

1. Clathrocircus hexaporus, n. sp.

Sagittal ring circular, smooth, with three pairs of pores (one apical and two basal). The two
apical pores are triangular, with two lateral spines, and correspond to the two mitral gates of the
Tympanida. The four basal pores form a hexagonal basal plate, with six lateral spines, and
correspond to the four basal pores of Semantrum; the two jugular are pear-shaped, and half as
broad as the two triangular cardinal pores.

Dimensions. — Height of the sagittal ring 0'08, breadth 0'06.

Habitat. — Cosmopolitan ; Atlantic, Pacific, many Stations, surface.

2. Clathrocircus octoporus, n. sp.

Sagittal ring elliptical, smooth, with four pairs of pores (two apical and two basal). The four
apical pores are of nearly equal size, subcircular, and form a regular cross around the apical pole.
The four basal pores are ovate, and form a quadrangular plate, armed with marginal thorns ; the
two jugular pores are somewhat smaller than the two cardinal pores.

Dimensions. — Height of the sagittal ring Oil, breadth 0'08.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

3. Clathrocircus decaporus, n. sp.

Sagittal ring ovate, thorny, with five pairs of pores (two apical and three basal). The four
apical pores are roundish and form a cross. The six basal pores are triangular and form a
hexagonal plate with thorny margin ; the two jugular pores are somewhat larger than the two
cervical, and half as broad as the two cardinal pores.

Dimensions. — Height of the sagittal ring 0'09, breadth 0-07.

Habitat. — North Pacific, Station 256, depth 2950 fathoms.

4. Clathrocircus stapedius, n. sp. (PI. 92, fig. 8).

Sagittal ring ovate, smooth, with six pairs of pores (two apical and four basal). The four
apical pores are of nearly equal size and form a quadrangular mitral plate with two large lateral
horns. The eight basal pores are of very different size (the four central far larger than the two
anterior and the two posterior), and form a hexagonal basal plate, also with two large lateral horns.
The four branched lateral horns (two upper and two lower) form together an incomplete frontal ring.

Dimensions. — Height of the sagittal ring 01, breadth 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

REPORT ON THE RADIOLARIA. 963

5. Clathrocircus dictyospyris, n. sp. (PL 92, fig. 9).

Sagittal ring ovate, thorny, with eight pairs of pores. The four apical and the four basal pores
are elliptical and far larger than the four dorsal and the four ventral pores. Eesembles a
Dictyospyris with open lateral gates.

Dimensions. — Height of the sagittal ring 0'08, breadth 0'06.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Clathrocircus multiforis, n. sp. (PI. 92, fig. 10).

Sagittal ring circular, smooth, with ten to twelve pairs of roundish pores, forming together a
complete lattice-girdle with two parallel circular rows of pores. Four larger of these are the four
gates of the basal ring (two jugular and two cardinal pores).

Dimensions. — Diameter of the ring O'l to 015, breadth 0'03 to 0'05.

Habitat.— Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

Subfamily 2. CORTINISCIDA, Haeckel.

Definition. — S emantida with large, typical, regularly disposed basal feet (originally
three cortinar feet, one odd caudal and two paired pectoral).

Genus 411. Cortiniscus,1 n. gen.

Definition. — S emantida with three typical basal feet (an odd caudal foot and two
paired lateral or pectoral feet).

The genus Cortiniscus is of peculiar importance, as the common ancestral form of the
Cortiniscida, or those Semantida in which the basal ring is provided with typical,
regularly disposed basal feet — three, four, or six. Since these typical basal feet (or
" cortinar feet ") are preserved in the greater number of all NASSELLARIA, determining
their triradial structure, they possess a great morphological value. Cortiniscus exhibits
the same three primary feet as Cortina, from which it differs in the production of two
or more basal pores (between the odd caudal and the paired lateral feet).

1. Cortiniscus tripodiscus, n. sp. (PI. 92, fig. 11).

Sagittal ring ovate, thorny, with three prominent, distorted edges ; its dorsal rod nearly
straight and vertical, with one or two pairs of short thorns ; its ventral rod strongly curved, with
three or four pairs of divergent thorns. Basal ring larger than the sagittal ring, with two
semicircular gates and obliquely ascending halves, which on the inner and lower edge are smooth,

1 Cortiniscus= Small cortina or tripod.

964 THE VOYAGE OF H.M.S. CHALLENGER.

on the outer and upper thorny. Apical horn and the three divergent feet nearly equal, straight,
about as long as the sagittal ring, with three thorny edges.

Dimensions. — Height of the sagittal ring 01 to 012, breadth 0'07 to 0'09.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

2. Cortiniscus dipylaris, n. sp. (PL 92, fig. 13).

Sagittal ring nearly semicircular, with prominent distorted edges and six pairs of small
roundish papillate tubercles (three pairs on the straight dorsal, three on the curved ventral rod).
Apical horn short and stout, with a tuberculate knob. Basal ring smaller than the sagittal ring
with two elliptical gates. Three feet short and stout, irregularly branched like a cauliflower, with
numerous short papillate tubercles.

Dimensions. — Height of the sagittal ring Oil, breadth 0'08.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Cortiniscus tripylaris, n. sp.

Sagittal ring elliptical, smooth. Apical horn conical, smooth. Basal ring larger than the
sagittal ring, with three elliptical gates of equal size ; two paired, posterior (jugular pores) between
the basal parts of the caudal foot and the two pectoral feet), and an odd, anterior (sternal pore)
between the basal parts of the two pectoral feet and a connecting horizontal convex sternal bow.

Dimensions. — Height of the sagittal ring 0'09, breadth 0'06.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

4. Cortiniscus tetrapylaris, n. sp.

Sagittal ring elliptical, with four pairs of short branched thorns, two posterior on the straight
dorsal, and two anterior on the curved ventral rod. Basal ring smaller than the sagittal ring, with
four triangular gates ; the two anterior (jugular pores) a little smaller than the two posterior
(cardinal pores). Apical horn and the three divergent feet shorter than the sagittal ring, irregularly
branched, with curved, often tuberculate branches.

Dimensions. — Height of the sagittal ring 0'08 to 0'012, breadth 0'06 to 01.

Habitat. — Fossil in Barbados.

5. Cortiniscus typicus, n. sp. (PI. 92, fig. 12).

Sagittal ring ovate, thorny, with three distorted edges ; dorsal rod nearly straight and vertical
prolonged upwards into a stout thorny apical horn, downwards into the caudal foot. Basal ring
smaller than the sagittal ring, with four elliptical or nearly triangular gates ; the two anterior
(jugular pores) about half as large as the two posterior (cardinal pores). Three feet of equal size,
thorny, divergent, straight or slightly curved, about as long as the diameter of the sagittal ring.

Dimensions. — Height of the sagittal ring 014 to 018, breadth 01 to 012.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, at various depths.

REPORT ON THE RADIOLARIA. 965

Genus 412. Stephaniscus,1 n. gen.

Definition. — S emantida with four typical basal feet (two sagittal and two
lateral or pectoral feet).

The genus Stephaniscus differs from the preceding Cortiniscus in the production of
a fourth (sternal) foot, and therefore exhibits the same relation to it that Stephanium
among the Stephanida bears to Cortina. It differs from Stephanium in the pro-
duction of a basal ring, with pores or gates between the bases of the basal feet. Two
of these feet are sagittal (the posterior caudal and the anterior sternal foot), whilst the
other two are lateral or pectoral (right and left). The basal lattice-plate exhibits
either two pores (" jugular gates ") or four pores (two anterior jugular and two posterior
cardinal gates).

1. Stephaniscus tetrapodius, n. sp.

Sagittal ring nearly circular, smooth, with a short conical apical horn. Basal ring square,
smooth, with two triangular gates. Four feet simple, equal, conical, divergent, about as long as the
diameter of the ring.

Dimensions. — Height of the sagittal ring 0-08, breadth 0'07.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

2. Stephaniscus quadrifurcus, n. sp. (PI. 92, fig. 14).

Sagittal ring subcircular, thorny, with a small thorny apical horn. Basal ring also nearly
circular, with two large semicircular gates and a few small thorns. All four feet curved and forked,
the fork-branches again ramified, with numerous short curved and pointed branches. The two
lateral feet (right and left) are larger and more branched than the two sagittal feet (sternal and
caudal foot).

Dimensions. — Height of the sagittal ring 0'12, breadth O'l.

Habitat. — Central Pacific, Station 266,. depth 2750 fathoms.

3. Stephaniscus quadrigatus, n. sp. (PI. 92, fig. 15).

Sagittal ring oblique, ovate, with three prominent thorny edges ; its dorsal rod nearly straight
and vertical, the ventral rod strongly curved ; apex with a small curved horn. Basal ring with a few
short thorns and four gates of different size ; the two anterior (jugular pores) ovate or nearly
triangular, two-thirds as broad as the two posterior subcircular or pentagonal (cardinal pores). All

1 Stephaniscus = Small coronet or garland; oTHp

966 THE VOYAGE OF H.M.S. CHALLENGER.

four feet simple, curved, with three edges, the posterior (caudal) foot larger, the anterior (sternal)
foot smaller than the two lateral (pectoral) feet.

Dimensions. — Height of the sagittal ring 0'09, breadth 0'07.

Habitat. — Tropical Atlantic, Station 351, surface.

4. Stephaniscus medusinus, n. sp.

Sagittal ring elliptical, thorny, with a larger apical horn. Basal ring nearly square, with short
marginal thorns and four large ovate gates of nearly equal size. All four feet of equal size
divergent, curved, irregularly branched, with short curved branches.

Dimensions. — Height of the sagittal ring 013, breadth 0'09.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 413. Semantiscus,1 n. gen.

Definition. — S emantida with six typical basal feet (two sagittal, two pectoral,
and two tergal feet).

The genus Semantiscus may be the archetype of those NASSELLARIA which exhibit
six typical basal feet, in combination with the sagittal ring. Three of these are the
primary feet of Cortina and Cortiniscus, the other three are secondary productions
between the former. The basal ring may possess either two, four, or six basal pores.

1. Semantiscus hexapodius, n. sp. (PI. 92, fig. 16).

Sagittal ring elliptical, with a large branched apical horn. Basal ring small, square, with two
small triangular gates (or jugular pores). Prom its periphery there arise six short and stout
cylindrical feet, one very large (caudal) from the posterior corner, two tergal on each side, two
opposite (pectoral) from the kteral corners, and one odd sternal from the anterior corner. All six
spines bear a bunch of ten to twenty stout pointed conical branches, partly simple, partly forked.

Dimensions. — Height of the sagittal ring 0'12, breadth 0'08.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Semantiscus hexaspyris, n. sp. (PI. 92, fig. 18).

Sagittal ring semicircular, broad, latticed, with two pairs of irregular dorsal and two pairs of
ventral pores. The dorsal rod is straight and vertical, prolonged upwards into a short serrate apical
horn, downwards into a straight linear caudal foot. The ventral rod is curved and prolonged into a
similar sternal foot. Basal ring hexagonal, with four ovate gates (two smaller jugular and two
larger cardinal pores); its four lateral corners prolonged into four curved thorny lateral feet (two

1 Semantiscus = Small signet-ring

REPORT ON THE RADIOLARIA. 967

anterior larger pectoral, and two posterior smaller tergal feet). This species may be regarded as a
commencing Hexaspyris or Lirwspyris.

Dimensions. — Height of the sagittal ring O08, breadth 0'06.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Semantiscus hexapylus, n. sp. (PI. 92, fig. 17).

Sagittal ring ovate, thorny, with a small apical horn. Basal ring with six roundish or nearly
triangular gates; the -two jugular pores are smaller than the two cardinal and larger than the two
cervical pores. The separating bars between these six pores are prolonged into six straight, thorny
widely divergent feet ; three larger feet (the caudal and the two pectoral) with a pair of apophyses
three smaller between them simple (the sternal and the two tergal feet).

Dimensions. — Height of the sagittal ring 0'13, breadth 0'09.

Habitat. — "Western Tropical Pacific, Station 225, depth 4475 fathoms.

Family L. CORONIDA, Haeckel.

Triostephida, Haeckel, 1881, Prodromus, p. 445.

Definition. — S tephoidea with two crossed vertical rings, perpendicular one to
the other (the primary sagittal and the secondary frontal ring). Usually their
common base bears a horizontal basal ring, but a mitral ring (or a horizontal ring at
the apex) is never developed.

The family Coronida comprises those Stephoidea in which the primary
sagittal ring (of the Stephanida and Semantida) becomes crossed by a second vertical
ring, the lateral or frontal ring. Between these two vertical meridian rings, perpen-
dicular to one another, four large apertures remain constantly open, the " lateral " gates.
But besides these four constant openings, usually (excepting only in the Zygo-
stephanida) other gates are developed on the common base of the two crossed rings,
produced by a third, horizontal, basal ring. These basal gates are the same which we
have found already in the Semantida.

The distinction of the Coronida from the other Stephoidea is always easy. In
the Stephanida and Semantida, the frontal ring, or the second meridian ring, which
we find in all Coronida, is never developed. On the other hand these latter never
exhibit the typical "mitral ring," or the second, upper, horizontal ring, which
distinguishes the Tympanida.

We distinguish here, among the Coronida, four different subfamilies, which perhaps
afterwards may be better separated as families. Of these four groups the Zygo-
stephanida and Acanthodesmida exhibit the nearest relationship to the Stephanida,
whilst the Eucoronida and Trissocyclida possess a closer affinity with the Semantida.

968 THE VOYAGE OF H.M.S. CHALLENGER.

The Zygostephanida, constituting the first subfamily, exhibit four large gates only,
and differ from all other Coronida in the absence of a basal ring and of basal gates.
Therefore the skeleton is entirely composed of two crossed vertical rings, perpendicular
to one another ; the first is the primary or sagittal ring (inherited from the Stephanida),
the second is the new lateral or frontal ring. The four large lateral gates are either quite
simple (Zygostephanus) or partly closed by loose and irregular lattice-work (Zygo-
stephanium). The Zygostephanida may be derived directly from the Stephanida by
development of lateral branches forming a frontal ring. They commonly possess the
same characteristic spines or branches, and the same typical difference between the straight
dorsal rod and convex ventral rod of the sagittal ring, which we found in the greater
number of Stephanida. The frontal ring is commonly elliptical or kidney-shaped, and
much larger than the ovate sagittal ring.

The Acanthodesmida, forming the second subfamily of Coronida, differ from all other
members of this family in the possession of a large simple basal gate, surrounded by a
simple horizontal basal ring. Only this ring is complete, whilst the two crossed vertical
meridian rings (the primary sagittal and the secondary frontal ring) are incomplete,
both truncated at the base by the basal ring. Therefore there remain here between the
three rings five large gates (recognised previously by Johannes Miiller in 1856 mAcantho-
desmid) : four lateral gates (the same as in the Zygostephanida) and one central basal
gate. The latter is always quite simple, and serves for the emission of the pseudo-
'podia, arising from the basal pole of the central capsule. The four lateral gates
are either quite simple (Coronidium) or partly closed by irregular loose lattice-work
(Acanthodesmia). The subfamily Acanthodesmida may be derived either directly from
the Stephanida (by development of a central basal gate) or from the Eucoronida (by
loss of the basilar part of the sagittal ring).

The Eucoronida, the third subfamily, are the most important group of the Coronida ;
their numerous species are much more frequent and more widely distributed than those
of the other three subfamilies. They may be derived immediately from, the Semautida
by the development of a lateral or frontal ring. This remains incomplete in the basal
part, whilst the two other rings, perpendicular to it (the vertical sagittal ring and the
horizontal basal ring), are complete. Therefore the shell constantly exhibits six large
open gates between the three rings ; four lateral gates (the same as in the Zygo-
stephanida and Acanthodesmida) and two basal gates (inherited from Semantis) ; the
latter correspond to the " jugular pores " of the Spyroidea and Cyrtoidea; they
remain constantly simple. The four lateral gates may also remain simple (Eucoronis)
or they may become partly closed by irregular loose lattice-work (Plectocoronis) . The
remarkable genus Podocoronis is distinguished by the development of typical descending
basal feet, which are regularly disposed and correspond to the typical " cortinar feet " of
the other NASSELLAEIA. There may be developed either two lateral feet (as lower

REPORT ON THE RADIOLARIA. 969

prolongations of the segments of the frontal ring), or three feet (one caudal and two
pectoral, as in Cortina and Cortiniscus), or four feet (two sagittal and two lateral, as in
Stephanium and Stephaniscus), or six feet (two sagittal, two pectoral, two tergal, as in
Semantiscus), sometimes numerous feet (as in Petalospyris and Anthocyrtis, &c.).

The Trissocyclida represent the fourth and last subfamily of Coronida, distinguished
from all others in the possession of three complete rings, perpendicular one to another,
and of eight large gates separated by them. Two of the three rings are vertical (the
primary sagittal and the secondary frontal ring), the third is horizontal (the basal
ring). The four upper gates correspond to the four lateral gates of the preceding three
subfamilies ; the four lower gates are the same as the four basal gates of Semantrum (two
primary jugular and two secondary cardinal gates) ; therefore the Trissocyclida may be
derived directly from these Semantida by development of a complete frontal ring.
Probably the two jugular gates were . originally smaller than the two cardinal, but
usually they have become equal. In Tristephanium (the common ancestral form of the
Trissocyclida) and in the closely allied Tricyclidium the four basal gates remain smaller
than the four lateral gates. But in two other genera, Trissocircus and Trissocyclus,
the four lower or basal gates reach the same size as the four upper or lateral gates ;
therefore all eight gates become equal and the basal ring becomes equatorial. In the
most regular species of the latter genera also the three rings become perfectly equal and
cannot be any longer distinguished. Here the original bilateral (or dipleuric) funda-
mental form of the shell passes over into a regular cubic, or octahedral form (with three
equal, isopolar axes, perpendicular one to another). The eight large gates of the
Trissocyclida usually remain simple (Tristephanium, Trissocircus), but sometimes they
become partly closed by loose lattice-work (Tricyclidium, Trissocyclus).

The original rings, and the secondary rods or bars, composing the loose framework
of the Ooronida are either roundish (with circular or elliptical transverse section) or
three-edged (with triangular transverse section), rarely quadrangular or provided with
distorted edges. The branches or spines arising from them, are either simple or
branched, and offer a great variety in number, form, and disposition. The most
important forms are those which develop the three typical basal feet of Cortina, e.g.,
Podocoronis cortina (PI. 97, fig. 2).

The Central Capsule of the Coronida is the same as in the other Stephoidea (comp.
p. 937), and offers all those characteristic peculiarities of "Monopylea" which we have
mentioned above in the general description of the NASSELLARIA (p. 890). Usually it is
spherical or ellipsoidal, often violin-shaped or bilobed, with a sagittal constriction. The
porochora of its basal pole is in close contact with the base of the sagittal ring.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr.122

970

THE VOYAGE OF H.M.S. CHALLENGER.

I. Subfamily

Zygostephanida.
Four lateral gates (no
basal gate).

II. Subfamily

Acanthodesmida.
Five large gates (four
lateral and one simple
basal).

III. Subfamily

Eucoronida.

Six large gates (four
lateral and two basal).

IV. Subfamily

Trissocyclida.
Eight large gates (four -

upper lateral and four

lower basal).

Synopsis of the Genera of Coronida.

Two meridional rings ~|

S^^l*-^ gates simple,
dicular to one f ,-, , ,

another (no basal | Four lateral 8ates Partly latticed'
ring). J

Two meridional rings ")

(sagittal and frontal) \ v , . ,

incomplete, both I Four lateral 8ates 8lmPle'

truncated by the [ -, , .

complete horizontal | Four lateral Sates Partly latticed'

basal ring. J

Two rings (the sagittal
meridional ring and
the horizontal basal
ring) complete, the
frontal meridian
ring incomplete.

Two meridional rings
(sagittal and frontal)
and the horizontal
basal ring complete. -
All three complete
rings perpendicular
to one another.

Basal ring f Gates simple, .
without larger I
descending 1 Gates partly lat-
feet. [ ticed,

Basal ring with large, regularly
disposed, descending feet. Gates
simple,

414. Zygostephamis.

415. Zygostephanium.

416. Coronidium.

417. Acantkodesmia.

418. Eucoronis.

419. Plectocoronis.

420. Podocoronis.

Four upper
gates larger

than the
four lower.

Gates simple, . 421. Tristephanium.

Gates partly lat-
ticed,

{Gates simple, .
Gates partly lat-
ticed,

422. Tricydidium.

423. Trissoeir/MS.

424. Trissocydus.

Subfamily 1. ZYGOSTEPHANIDA, Haeckel, 1881, Prodromus, p. 446.

Definition. — C o r o n i d a with four large lateral gates, without basal gate. Skeleton
composed of two complete vertical rings, perpendicular one to another — the primary
sagittal and the secondary frontal ring.

Genus 414. Zygostephanus,1 Haeckel, 1862, Monogr. d. Eadiol, p. 268.

Definition. — C o r o n i d a with four large, simple, lateral gates, without basal gate
and lattice-work. Skeleton composed of two simple meridional rings, perpendicular to
one another.

The genus Zygostephanus, founded by me in 1862 for the Mediterranean Zygoste-
phanus mulleri, is the simplest and most primitive of all the Coronida, and may there-

1 Zygostephamis — Yoked ring ; £vyov,

REPORT ON THE RADIOLARIA. 971

fore be regarded as the common ancestral form of this family. The simple skeleton
is composed of two meridional rings only, perpendicular one to another — a sagittal and
a frontal ring.

Subgenus 1. Zygostephus, Haeckel, 1881, Prodromus, p. 446.

Definition. — The two vertical rings of nearly equal height, therefore without
sagittal constriction.

1. Zygostephanus dissocircus, n. sp. (PI. 93, fig. 1).

Both rings elliptical, of nearly equal height, smooth, without spines. Frontal ring somewhat
longer than the sagittal. No sagittal constriction.

Dimensions. — Height of the rings 0'07, breadth O'l.

Habitat. — Cosmopolitan; Mediterranean, Atlantic, Pacific, surface.

2. Zygostephanus serratus, n. sp.

Both rings elliptical, of nearly equal height, with a serrate prominent edge on the outer
convexity (in the transverse section three-edged). No sagittal constriction.
Dimensions. — Height of the rings 0'08, breadth 012.
Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Zygostephanus miilleri, Haeekel.

Zygostephanus miilleri, Haeckel, 1862, Monogr. d. Radiol., p. 268, Taf. xii. fig. 2.

Both rings elliptical, of nearly equal height, armed with numerous (about fifty) slender curved
spines, as long as the radius of the rings ; commonly each ring with twelve pairs of divergent spines.
No sagittal constriction.

Dimensions. — Height of the rings 0'06, breadth O'l.

Habitat. — Mediterranean (Messina), surface.

4. Zygostephanus ratnosus, n. sp.

Both rings elliptical, of nearly equal height, armed with numerous branched spines, which are
arranged on each ring in two divergent rows ; the branches of the spines are curved and partly
protect the open gates. No sagittal constriction.

Dimensions. — Height of the rings 0'07, breadth 0'09.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

972 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 2. Zygostephaniscus, Haeckel, 1881, Prodromus, p. 446.

Definition. — The two vertical rings of different heights; the frontal ring higher
than the sagittal ring, therefore with a sagittal constriction in the median plane.

5. Zygostephanus reniformis, n. sp.

Frontal ring kidney-shaped, in the upper half convex, in the lower half concave, in the latter
with a deep sagittal constriction, armed with numerous irregular short spines. Sagittal ring
thicker and lower, only two-thirds as high, with four pairs of short divergent spines (two ventral
and two dorsal pairs).

Dimensions. — Height of the frontal ring 013, hreadth 0'2.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

6. Zygostephanus violina, n. sp.

Frontal ring violin-shaped, on the upper and the lower margin concave, with a deep sagittal
constriction, armed with numerous irregular spines, which are partly simple, partly branched.
Sagittal ring thicker and lower, only half as high, with a few short conical spines at the apical and
hasal poles.

Dimensions. — Height of the frontal ring 012, breadth 018.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

7. Zygostephanus bicornis, n. sp. (PI. 93, fig. 2).

Frontal ring violin-shaped, on the upper and the lower margin concave, with a deep sagittal con-
striction ; its two halves pentagonal. Between numerous smaller spines there arise from the frontal
ring six groups of larger branched spines, two odd in the corners of the highest points (curved like
two horns), two branched pairs on the prominent lateral corners (at right and left), and two pairs in
the corners of the lowest points (like four branched basal feet). Sagittal ring only two-thirds as
high, with four pairs of irregular spines.

Dimensions. — Height of the frontal ring Oil, breadth 016.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

Genus 415. Zygostephanium,1 Haeckel, 1881, Prodromus, p. 446.

Definition. — C o r o n i d a with four large, partly latticed, lateral gates, without
basal gate. Skeleton composed of two meridional rings perpendicular to each other.

The genus Zygostephanium differs from the preceding ancestral genus Zygostephanus
in the development of lattice-work along the two crossed rings, produced by their anasto-
mosing branches. Therefore the four large lateral gates between them, which are quite
simple, in the preceding genus here become more or less fenestrated.

1 Zygostephanium = Small yoked ring ; £vyoi>,

REPORT ON THE RADIOLARIA. 973

i

1. Zygostephanium dizonium, n. sp. (PI. 93, fig. 3).

Tympaniscus dizonius, Haeckel, 1882, Manuscript

Both rings elliptical, of nearly equal height, smooth, without spines. Sagittal ring with four
pairs of small pores (two apical pairs and two basal pairs). Frontal ring with three pairs of small
pores (one pair lateral, one pair above and one pair below).

Dimensions. — Height of the frontal ring 0'08, breadth 012.

Habitat. — Central Pacific, Station 263, depth 2900 fathoms.

2. Zygostephanium paradictyum, n. sp. (PI. 93, fig. 4).

Frontal ring kidney-shaped, in the upper half convex, in the lower concave, in the latter with
a deep sagittal constriction. Sagittal ring ovate, ubout two-thirds as high as the frontal ring. Both
rings three-edged, armed with numerous short and branched bristle-shaped spines, which anasto-
mose along their three edges and produce two series of irregular polygonal pores.

Dimensions. — Height of the frontal ring 0'08, breadth 0'13.

Habitat. — North Pacific, Station 236, surface.

3. Zygostephanium constrictum, n. sp.

Frontal ring violin-shaped, concave on the upper and lower margins, with a deep sagittal
constriction. Sagittal ring ovate, about two-thirds as high as the frontal ring. Both rings covered
with numerous branched irregular spines, which partly anastomose along the edges of the rings, and
produce small irregular polygonal pores.

Dimensions. — Height of the frontal ring 012, breadth 018,

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subfamily 2. ACANTHODESMIDA, Haeckel, 1881, Prodromus, p. 445.

Definition. — C o r o n i d a with five large gates (four lateral and one basal).
Skeleton composed of three rings, perpendicular one to another, two of which are
vertical and incomplete (the primary or lateral, and the secondary or frontal), the third
is horizontal and complete (the tertiary or basal ring).

Genus 416. Coronidium,1 Haeckel, 1881, Prodromus, p. 445.

Definition. — C o r o n i d a with five large simple gates (four lateral and one basal).
Skeleton composed of two incomplete meridional rings and one complete basal ring,
without lattice-work.

1 Coronidium = Small crown ;

974 THE VOYAGE OP H.M.S. CHALLENGES.

The genus Coronidium and the following, nearly allied Acanthodesmia, form
together the peculiar subfamily of Acanthodesmida — not in the wider sense in which I
first founded this group (1862, Monogr. d. Kadiol., p. 265), but in the restricted sense,
which is exactly defined in my Prodromus (1881, p. 445). According to this definition,
the shell is composed of three different rings, perpendicular to one another ; only one of
these is complete, the simple horizontal basal ring ; the two others are incomplete and
vertical (the primary or sagittal and the secondary or frontal ring). Therefore there remain
constantly between the three rings five characteristic large openings or gates ; four of
these are lateral (between the halves of the two meridional rings), the fifth is basal,
enclosed by the horizontal basal ring. The longest known type of this subfamily is
Acanthodesmia vinculata, the five characteristic gates of which are clearly distinguished
by its discoverer, Johannes Miiller (" Das Gehause besteht nur aus den Leisten zwischen
fiinf grossen Liicken "). The Acanthodesmida may be derived from the Eucoronida by
reduction of the basilar rod of the sagittal ring. If in Eucoronis this basal rod be lost,
Coronidium arises.

1. Coronidium dyostephanus, n. sp. (PL 82, fig. 7).

Frontal ring elliptical, with few scattered thorns, twice as broad as high, and three times as
broad as the smooth rhombic basal ring. Sagittal ring semicircular, very stout, twice as thick as
the two other rings, with short lateral thorns (in the figure seen from the apical pole, which
exhibits a four-lobed dimple). Basal gate rhombic.

Dimensions. — Height of the frontal ring 0'08, breadth 0-16.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

2. Coronidium diadema, n. sp. (PI. 82, fig. 8).

Frontal ring kidney-shaped, one and a half times as broad as high, with a slight sagittal con-
striction. Sagittal ring ovate, smaller, about of the same size as the elliptical basal ring. Eods of
all three rings cylindrical, bearing numerous short and stout curved spines, partly simple, partly
branched. Four bunches of larger spines on the four corners of the basal ring, and one very large
bunch on the apical pole. Basal gate elliptical, one and a half times as broad as long.

Dimensions. — Height of the frontal ring 013, breadth 0'18.

Halitat. — Indian Ocean (Madagascar), Eabbe, surface.

3. Coronidium cervicorne, n. sp. (PI. 82, fig. 1).

Frontal ring kidney-shaped, twice as broad as high, one and a half times as broad as the
elliptical basal ring, both with a slight sagittal constriction. Sagittal ring ovate. All three rings

REPORT ON THE RADIOLARIA. 075

(in the figure seen from the apical pole) with cylindrical rods, armed with numerous stout spines,
branched like a deer's antler. Basal gate rather oblong, twice as broad as long.

Dimensions. — Height of the frontal ring 0'08, breadth 0'16.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Coronidium acacia, n. sp. (PI. 82, fig. 2).

Frontal ring and sagittal ring nearly circular, of equal size, truncated at the base. Basal ring
circular, somewhat smaller. All three rings with prominent edges, bearing bunches of short and
straight pointed spines, like those of an Acacia. Basal gate circular.

Dimensions. — Height of the frontal ring 0'12, breadth 0'14.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

Genus 417. Acanthodesmia,1 J. Miiller, 1856, Monatsber. d. k. preuss.
AJsad. d. Wiss. Berlin, p. 485.

Definition. — C o r o n i d a with five large, partly latticed gates (four lateral and one
basal). Skeleton composed of two incomplete, partly fenestrated meridional rings, and
one complete basal ring.

The genus Acanthodesmia, the oldest known form of all Coronida, diifers from the
preceding Coronidium, its ancestral form, in the development of irregular loose lattice-
work along the rings, and therefore bears to it the same relation that Zygostephanium
does to Zygostephanus. The first species described by Johannes Miiller, Acantho-
desmia vinculata ("with five large gates between the bars of the shell") remains the
true type of this genus ; the second species described by him (Acanthodesmia dumetum)
belongs to the Plectanida (Polyplecta).

1. Acanthodesmia vinculata, J. Miiller.

Acanthodesmia vinculata, J. Miiller, 1858, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 30, Taf. i.

figs. 4-6 (non 7).
Lithodrcus vinculutus, J. Miiller, 1856, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 484.

Frontal ring violin-shaped, one and a half times as broad as high, with a sagittal constriction.
Sagittal ring ovate, smaller. The four gates between the two rings are partly fenestrated by a few
thin threads, irregularly branched and connecting the two rings. A few short thorns are scattered
here and there. Basal gate elliptical.

Dimensions. — Height of the frontal ring 0-12, breadth 0-18.

Habitat. — Mediterranean (Nice), Atlantic (Canary Islands), surface.

1 Acanthodesmia = Thorn-band ; dx.ayf)a,

976 THE VOYAGE OF H.M.S. CHALLENGER.

2. Acanthodesmia ceratospyris, n. sp.

Frontal ring violin-shaped, one and a half times as broad as high, with a deep sagittal con-
striction. Sagittal ring semicircular, half as high as the frontal ring. The four gates between
the two rings are partly fenestrated by anastomosing branches of the numerous, irregularly branched
spines, which cover all three rings. Basal gate nearly circular, smaller than the sagittal ring,

Dimensions. — Height of the frontal ring O08, breadth 0-12.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Acanthodesmia corona, n. sp. (PL 93, fig. 5).

Frontal ring kidney-shaped, nearly twice as broad as high, with a flat sagittal constriction.
Sagittal ring semicircular. The four gates between the two rings are partly fenestrated by an
arachnoidal network, composed of thin, irregularly branched threads, arising from the rings. The edges
of all three rings are armed with irregular thorns. Basal gate circular, larger than the sagittal ring.

Dimensions. — Height of the frontal ring 0'08, breadth 0' 14.

Habitat. — Indian Ocean (Madagascar), Eabbe, surface.

4. Acanthodesmia mulleri, n. sp.

Frontal ring kidney-shaped, with a deep sagittal constriction. Sagittal ring ovate. The four
gates between the two rings irregularly fenestrated, with a few large polygonal meshes. Edges of
the rings with a few scattered thorns. Basal gate violin-shaped.

Dimensions. — Height of the frontal ring O'l, breadth O16.

Habitat. — Tropical Atlantic, Station 347, surface.

Subfamily 3. EUCORONIDA, Haeckel, 1881, Prodromus, p. 445.

Definition. — C o r o n i d a with six large gates (four lateral and two basal gates).

Skeleton composed of three rings perpendicular to one another, two of which are

complete (the vertical sagittal, and the horizontal basal ring) ; the third is incomplete
.(the vertical frontal ring).

•.Genus 418. Eucoronis,1 Haeckel, 1881, Prodromus, p. 445.

Definition. — C o r o n i d a with six large simple gates (four lateral and two basal).
Skeleton composed of two complete rings (the sagittal and basal) and one incomplete
(frontal) ring. Basal ring without typical feet.

1 Eworonis=Good crown; ev,

REPORT ON THE RADIOLARIA. 977

The genus Eucoronis and the following two nearly allied genera (Plectocoronis and
Podocoronis) compose together the important subfamily Eucoronida. In this typical
main group of Coronida the shell is constantly composed of three rings and six gates.
The vertical sagittal ring and the horizontal basal ring are complete (as in the Semantida);
the vertical frontal ring is incomplete. Between these three rings remain six large
open gates, the four upper (or lateral) are always much larger than the four lower
(or basal gates). Eucoronis may be derived from Semantis by development of the
frontal ring.

Subgenus 1. Acrocoronis, Haeckel, 1881, Prodromus, p. 445.
Definition. — Kings smooth or rough, armed with numerous short spines or thorns.

1. Eucoronis perspicillum, n. sp. (PL 82, fig. 6).

Frontal ring elliptical, twice as broad as high, with a slight constriction at the apical pole,
armed with three pairs of short conical spines, one apical pair (near the constriction) and two
lateral pairs (one upper and one lower pair). Sagittal ring of the same height, half the breadth
and double the thickness, also armed with three pairs of spines (one basal, one dorsal, and one
ventral pair).

Dimensions. — Height of the frontal ring OH, breadth 0'22.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

2. Eucoronis Icevigata, n. sp.

Frontal ring elliptical, smooth, one and a half tunes as broad as high, without sagittal constric-
tion, with horizontal basal gates. Sagittal ring of the same height and thickness, also elliptical
and smooth. No spines on either of the smooth rings.

Dimensions. — Height of the frontal ring 01, breadth 015.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Eucoronis nephrospyris, n. sp. (PL 82, fig. 5).

Frontal ring kidney-shaped, in the upper half convex, in the lower concave, with a sagittal
constriction (often much deeper than in the specimen figured). Sagittal ring ovate, about two-
thirds as high as the frontal ring. Eods of both rings without edges, cylindrical, armed with
numerous short conical thorns.

Dimensions. — Height of the frontal ring 01 to 012, breadth 015 to 018.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, many Stations, surface and
at various depths.

(ZOOL. CHALU EXP. PART XL. — 1886.) Rr 123

978 THE VOYAGE OF H.M.S. CHALLENGER.

4. Eucoronis angulata, n. sp. (PL 82, fig. 3).

Frontal ring violin-shaped, twice as broad as high, on the upper and the lower margin concave,
with a deep sagittal constriction. Sagittal ring pentagonal, with straight horizontal basal rod, two-
thirds as high as the frontal ring. Eods of both rings with sharp prominent edges, bearing
numerous short pyramidal spines.

Dimensions. — Height of the frontal ring 0'09, breadth 017.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subgenus 2. Lithocoronis, Haeckel, 1881, Prodromus, p. 445.
Definition. — Rings armed with numerous large, branched or arborescent spines.

5. Eucoronis cervicornis, n. sp.

Frontal ring kidney-shaped, in the upper half convex, in the lower concave, with sagittal con-
striction. Sagittal ring ovate, two-thirds as high as the frontal ring. Both rings armed with
numerous stout spines, irregularly branched like a deer's antler. (Very similar to Coronidiuni
cervicorne, PL 82, fig. 1, which I formerly confounded with it, but differing in the complete
sagittal ring, which in the latter form is incomplete and has lost its basal part.)

Dimensions. — Height of the frontal ring 012, breadth 0'2.

Habitat. — Central Pacific, Station 264, surface.

6. Eucoronis arborescens, n. sp.

Frontal ring kidney-shaped, with a deep sagittal constriction in the concave basal part. Sagittal
ring ovate, half as high as the frontal ring. Both rings armed with numerous thin, richly branched
and arborescent spines (branches much thinner and more numerous than in the preceding and
following species).

Dimensions. — Height of the frontal ring 015, breadth 0'25.

Habitat. — Equatorial Atlantic, Station 247, surface.

7. Eucoronis challengeri, n. sp. (PL 82, fig. 4).

Lithocoronis challengeri, Haeckel, 1881, Prodromus, p. 445.

Frontal ring violin-shaped, one and a half times as broad as high, with a strong sagittal con-
striction. Sagittal ring nearly circular, two-thirds as high as the frontal ring. Both rings armed
with numerous irregularly branched spines. (The specimen figured, with red central capsule and
numerous xanthellse, was observed living by me at the Canary Islands.)

Dimensions. — Height of the frontal ring 01 to 012, breadth 014 to 017.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, surface and at various depths.

REPORT ON THE RADIOLARIA. 979

Genus 419. Plectocoronis,1 Haeckel, 1881, Prodromus, p. 445.

Definition. — C o r o n i d a with six large, partly latticed gates (four lateral and two
basal). Skeleton composed of two complete rings (the sagittal and basal) and one
incomplete (frontal) ring. Basal ring without developed typical feet.

The genus Plectocoronis differs from the preceding Eucoronis, its ancestral form, in
the development of loose irregular lattice-work along the two meridional rings, and
therefore bears to it the same relation that Acanthodesmia does to Coronidium. If
the lattice-work become more complete and close the gates, these Coronida pass over
directly into Spyroidea (Zygospyrida).

1. Plectocoronis anacantha, n. sp.

Basal ring and frontal ring elliptical, without sagittal constriction. Sagittal ring ovate. The
frontal and sagittal rings are bordered on both edges with an incomplete series of small irregular
pores. All three rings smooth, without spines.

Dimensions. — Height of the frontal ring O'l, breadth 0'16.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

2. Plectocoronis triacantha, n. sp.

Basal ring and frontal ring nearly circular, without sagittal constriction. Sagittal ring
elliptical, prolonged at the apex into an apical horn from which two branched lateral bows descend
and unite with the uppermost parts of the frontal ring. Four other small bows descend from the
lowermost parts of the latter and unite with the basal ring. Prom the lateral corners of the basal
ring descend two short vertical feet. (May be regarded as derived from Podocoronis toxarium,
PI. 83, fig. 7, by development of the bows connecting the rings.)

Dimensions. — Height of the frontal ring O'll, breadth 013.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Plectocoronis pentacantha, n. sp. (PL 93, fig. 6).

Basal ring and frontal ring kidney-shaped, with deep sagittal constriction. Sagittal ring ovate,
prolonged at the apex into an oblique horn. From the edges of the angular rings delicate threads
arise, which anastomose and form irregular arachhoidal meshes, partly closing the four open
lateral gates. Two basal gates simple. From the four nodal points of the basal ring there arise
four, short diverging feet, comparable to rudimentary cortinar feet (two lateral from the frontal ring
and two sagittal from the primary ring, as basal prolongations).

Dimensions. — Height of the frontal ring 0'12, breadth O'IS.

Habitat. — Central Pacific, Station 271, surface.

1 Plectocoronis = Crown with framework;

980 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 420. Podocoronis,1 Haeckel, 1881, Prodromus, p. 445.

Definition.' — C o r o n i d a with six large gates (four lateral and two basal).
Skeleton composed of two complete rings (the sagittal and basal) and one incomplete
(frontal) ring. Basal ring provided with typical, regularly disposed, descending feet
(cortinar feet).

The genus Podocoronis differs from the two preceding nearly allied genera in the
development of typical radial feet on the basal ring, which by their regular disposition
and their general appearance among the Spyroidea and Cyrtoidea obtain
great morphological importance. According to the different number and disposition of
these basal feet (or " cortinar feet "), the following subgenera may be distinguished
(regarded in my Prodromus, 1881, p. 445, as separate genera) : — Dipocoronis with
two lateral feet, Tripocoronis with three cortinar feet (most important !), Tetracoronis
with four crossed feet, Hexacoronis with six radial feet, Stylocoronis with numerous
(8 or more feet). These subgenera have important relations to the corresponding genera
of Zygospyrida.

Subgenus 1. Dipocoronis, Haeckel, 1881, Prodromus, p. 445.

Definition. — Basal ring with two descending lateral feet (right and left) as pro-
longations of the frontal ring.

1. Podocoronis dipodiscus, n. sp.

Basal ring nearly circular, with two conical, straight, parallel descending feet, which are direct
lateral prolongations of the subcircular frontal ring, and half as long as it. The ovate sagittal ring
bears at the apex a short conical vertical horn. All rings nearly smooth.

Dimensions. — Height of the frontal ring 012, breadth 014.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Podocoronis toxarium, n. sp. (PI. 83, fig. 7).

Basal ring elliptical, with two descending; slightly curved conical feet, lateral prolongations of
the subcircular frontal ring. The ovate sagittal ring bears at the apex a cylindrical vertical horn,
which is connected by two descending lateral arches (or galear arches) with the uppermost part of
the frontal ring.

Dimensions. — Height of the frontal ring 01, breadth 013.

Habitat. — Central Pacific, Stations 265 to 268, depth 2900 fathoms.

1 Podocoronis = Crown with feet; irovf,

REPORT ON THE RADIOLARIA. 981

Subgenus 2. Tripocoronis, Haeckel, 1881, Prodromus, p. 445.
Definition. — Basal ring with three descending feet (one caudal and two pectoral).

3. Podocoronis cortiniscus, n. sp. (PL 97, fig. 2).

Basal ring violin-shaped, with three straight divergent thorny feet, about as long as the ovate
sagittal ring. The dorsal part of the latter is straight, vertical, and prolonged downwards into the
caudal foot, upwards into a stout, thorny, vertical apical horn. The ventral part is semicircular
and gives off the lateral branches, forming the kidney-shaped sagittal ring. All the rings and
their apophyses are armed with stout thorns. This and the following tripodal species may be
directly derived from Cortina.

Dimensions. — Height of the frontal ring 01, breadth 0'15.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

4. Podocoronis tripodiscus, n. sp.

Basal ring kidney-shaped, with three large divergent curved feet, nearly twice as long as the
semicircular sagittal ring. The straight dorsal part of the latter is prolonged downwards into the
caudal foot, upwards into a large branched apical horn, curved backwards. Differs from the
preceding species mainly in the longer curved apophyses and in the larger violin-shaped frontal
ring.

Dimensions. — Height of the frontal ring 012, breadth 0'2.

Habitat. — North Pacific, Station 238, surface.

Subgenus 3. Tetracoronis, Haeckel, 1881, Prodromus, p. 445.
Definition. — Basal ring with four descending feet (two sagittal and two lateral).

5. Podocoronis tetrapodiscus, n. sp.

Basal ring kidney-shaped, with four stout and straight divergent feet, about as long as the
sagittal ring ; two of them are lateral and arise from the basal corners of the violin-shaped frontal
ring (at its junction with the basal ring) ; two are sagittal, and arise from the basal corners of the
semicircular sagittal ring (one posterior caudal and one anterior sternal). The straight dorsal part
of the sagittal ring is prolonged upwards into an apical horn. All the rings are thorny.

Dimensions. — Height of the frontal ring 015, breadth 0'25.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Subgenus 4. Hexacoronis, Haeckel.

Definition. — Basal ring with six radial descending feet (two sagittal, two pectoral,
and two tergal feet).

982 THE VOYAGE OF H.M.S. CHALLENGER.

6. Podocoronis hexapodiscus, n. sp.

Basal ring violin-shaped, with six conical, vertically descending feet, half as long as the
sagittal ring ; two of them are sagittal (arising from the two basal corners of the sagittal ring,
caudal and sternal feet) ; the other four are lateral, and prolongations of the forked basal parts of the
frontal ring, which is inserted on the basal ring with two forked branches ; the anterior correspond
to the pectoral, the posterior to the tergal feet of Hexaspyris. All the rings are thorny.

Dimensions. — Height of the frontal ring Oil, breadth 017.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

Subgenus 5. Stylocoronis, Haeckel.
Definition. — Basal ring with numerous (eight to twelve or more) descending feet.

7. Podocoronis petalospyris, n. sp.

Basal ring violin-shaped, with ten to twelve flat lamellar, vertically descending feet, about as
long as the ovate sagittal ring. Frontal ring twice as broad as long, elliptical. All rings nearly
smooth. Similar to a Petalospyris without lattice- work.

Dimensions. — Height of the frontal ring 01, breadth 0'2.

Habitat. — Fossil in Barbados.

8. Podocoronis polypodiscus, n. sp.

•

Basal ring elliptical, with fifteen to eighteen conical, curved, descending feet, half as long as the
ovate sagittal ring. Frontal ring kidney-shaped, one and a half times as broad as long. All the
rings armed with short conical spines.

Dimensions. — Height of the frontal ring 012, breadth 018.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

Subfamily 4. TRISSOCYCLIDA, Haeckel, 1881, Prodromus, p. 446.

Definition. — C o r o-n i d a with eight large gates (four superior lateral and foul-
inferior basal). Skeleton composed of three complete rings, perpendicular to one
another ; two of which are vertical (the primary or sagittal and the secondary or
frontal ring), the third is horizontal (the tertiary or basal ring).

Genus 421. Tristephanium,1 Haeckel, 1881, Prodromus, p. 445.

Definition. — C o r o n i d a with eight large, simple gates of different sizes ; the four
upper or lateral gates larger than the four lower or basal gates. Skeleton composed of
three simple complete rings, perpendicular to one another.

1 Tristephanium = Small crown with three rings ; rfls, <rrf<p»m<».

REPORT ON THE RADIOLARIA. 983

The genus Tristephanium, and the three following genera derived from it, represent
together the interesting subfamily of Trissocyclida (Prodromus, 1881, p. 446). These
differ from all other Coronida in the possession of three complete rings, perpendicular
to one another. The first of these is the vertical sagittal ring, the second the vertical
frontal ring, and the third the horizontal basal ring. Since these three rings lie in the
three dimensive planes, they are perpendicular to one another ; and between them
remain eight large open gates. Originally the four upper or lateral gates (corresponding
to those of Zygostephanus) are much larger, the four lower or basal gates (corresponding
to those of Semantrum) much smaller ; but afterwards the latter may reach the size of
the former, so that the basal ring becomes equatorial (in Trissocircus and Trissocyclus).
The common ancestral form of the Trissocyclida (Tristephanium) may be derived directly
either from Semantrum (by complete development of the frontal ring) or from
Eucoronis (by complete development of four basal gates).

Subgenus 1. Triostephus, Haeckel, 1881, Prodromus, p. 445.
Definition. — Sagittal and frontal ring of different size and form.

1. Tristephanium dimensivum, n. sp. (PI. 93, fig. 9).

Sagittal ring ovate, with a large thorny apical horn, smaller than the two other rings. Frontal
ring violin-shaped, with a deep sagittal constriction. Basal ring also violin-shaped, in the sagittal
axis constricted. Its four gates (two jugular and two cardinal) of nearly equal size. All three
rings angular, armed with scattered, stout, thorny spines, which are larger in the basal half.

Dimensions. — Height of the frontal ring 0'08, breadth 0-12.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

2. Tristephanium octopyle, n. sp. (PI. 93, fig. 8).

Sagittal ring ovate, nearly smooth, smaller than the two other rings. Frontal ring kidney-
shaped, with a deep basal constriction. Basal ring violin-shaped. The jugular gates about half as
large as the cardinal gates. Eods of the rings cylindrical, with few scattered thorns.

Dimensions. — Height of the frontal ring 0'09, breadth 0'14.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Tristephanium hertwigii, Haeckel.

Acanthodesmia hertwigii, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. pp. 499, 539,
Taf. xxxii. figs. 9a-9e.

Sagittal ring ovate or nearly semicircular ; its dorsal rod straight, smooth (fig. 9c, a), its ventral
rod (&) curved, thorny. Frontal ring much larger, thorny, violin-shaped, with a slight sagittal con-

984 THE VOYAGE OF H.M.S. CHALLENGER.

striction. Basal ring smaller than the sagittal ring, thorny, kidney-shaped, with four different gates ;
the two cardinal pores much larger than the two jugular pores. (The four basal pores are often
much larger than in the specimen figured by Biitschli. Also the number, form, and size of the
spines is very variable.)

Dimensions. — Height of the frontal ring 0'07 to 0'09, breadth 017 to 0'2.

Habitat. — Fossil in Barbados.

Subgenus 2. Tristephaniscus, Haeckel, 1881, Prodromus, p. 445.
Definition. — Sagittal and frontal ring of equal size and form.

4. Tristephanium quadricorne, n. sp. (PL 93, fig. 7).

Sagittal and frontal ring of equal size and form, larger than the circular basal ring. From the
four corners, in which the latter crosses the two former, arise four strong, divergent spines, branched
like a deer's antler. Some smaller spines are scattered on the rings, and a bunch of four spines arises
on the apical pole. The four upper gates are triangular, the four lower nearly semicircular, the
latter of equal size, half as large as the former.

Dimensions. — Height of the frontal ring 013, breadth 014.

Habitat. — South Atlantic, Station 342, depth 1445 fathoms.

Genus 422. Tricyclidium,1 Haeckel, 1881, Prodromus, p. 446.

Definition. — C o r o n i d a with eight large, partly fenestrated gates ; the four
upper or lateral gates larger than the four lower or basal gates. Skeleton composed
of three latticed complete rings, perpendicular to one another.

The genus Tricyclidium differs from the preceding Tristephanium, its ancestral form,
in the development of loose rudimentary lattice -work along the rings, and therefore
bears to it the same relation that Plectocoronis does to Eucoronis. It may pass
directly over into Dictyospyris.

1. Tricyclidium dictyospyris, n. sp. (PI. 93, fig. 13).

Sagittal ring ovate, twice as thick as the two other larger rings, which become very thin, thread-
like at the lateral junction, and are both slightly violin-shaped, in the middle sagittal plane con-
stricted ; the frontal ring larger than the basal. All three rings bear small scattered spines, which
are irregularly branched, and by anastomoses of the thread-like branches form small irregular meshes
along the rings. The four basal gates are of equal size.

Dimensions. — Height of the frontal ring Oil, breadth 015.

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

1 Tricyclidium = Composed of three small crossed circles; TJ/?, *

REPORT ON THE RADIOLARIA. 985

2. Tricyclidium semantrum, n. sp.

Sagittal ring ovate, smaller than the violin-shaped frontal ring and larger than the elliptical
basal ring. All three rings of nearly equal thickness, armed with short irregular branches, which
are partly connected, and forming small irregular meshes along the rings. The four basal gates are
of different sizes ; the two anterior (jugular) gates only half as large as the two posterior (cardinal)

gates.

Dimensions. — Height of the frontal ring 0'12, breadth 018.
Habitat. — South Atlantic, Station 348, depth 2450 fathoms.

Genus 423. Trissocircus,1 Haeckel, 1881, Prodromus, p. 446.

Definition. — C o r o n i d a with eight large simple gates of equal size. Skeleton
composed of three simple complete rings, perpendicular to one another.

The genus Trissocircus, and the following nearly allied Trissocyclus, differ from
the two preceding ancestral genera in the remarkable growth of the four basal gates,
which reach the size of the lateral gates. Therefore both hemispheres of the shell (the
upper or apical and the lower or basal) here become equal, and the basal ring becomes
equatorial. Sometimes even all three rings attain the same size, so that it is difficult or
impossible to distinguish them. In this curious case the Coronida exhibit a striking
resemblance to some Sphseroidea.

Subgenus 1. Tricircarium, Haeckel.

Definition. — Sagittal ring smaller than the two other rings, which are both
elliptical.

1. Trissocircus lentellipsis, n. sp. (PI. 93, fig. 10).

All three rings elliptical, of different sizes, smooth, without spines. The sagittal ring is the
smallest, but two to three times as thick as the other two rings, which have the larger (trans-
verse) axis common. The smaller (sagittal) axis of the sagittal ring is also the smaller axis of the
equatorial ring, whilst the larger (principal) axis of the former is the smaller axis of the frontal ring,

Dimensions. — Height of the frontal ring 0'07, breadth O'l.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

2. Trissocircus binellipsis, n. sp. (PI. 83, fig. 6).

Sagittal ring circular, smaller than the other two rings, which are both equal, elliptical, slightly
constricted on the poles of the principal and transverse axes. The axis of the circular sagittal

1 Trissocircus — Composed of three crossed circles; T^IOUOS, x/jxo?.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 124

986 THE VOYAGE OF H.M.S, CHALLENGER.

ring is the shorter axis of the frontal and equatorial ring, and about half as long as their longer
axis. All three rings smooth, without spines.

Dimensions. — Height of the frontal ring 0'08, breadth 012.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Trissocircus octostoma (PL 93, fig. 11).

Sagittal ring circular, smaller than the other two rings, which are both equal, elliptical, distinctly
constricted at the poles of the principal and transverse axes. The axis of the circular sagittal
ring is the shorter axis of the frontal and equatorial ring, about one-third shorter than their longer
axis. All three rings armed with short, irregularly branched spines.

Dimensions. — Height of the frontal ring 01, breadth 012.

Habitat. — Indian Ocean, Ceylon (Belligemma), Haeckel, surface.

\

Subgenus 2. Tricirconium, Haeckel.
Definition. — All three rings equal, circular.

4. Trissocircus octahedrus, n. sp.

All three rings equal, circular, smooth, their rods cylindrical (in the transverse section circular).
Prom each pole of the three equal axes arises a short conical spine ; these six spines correspond to
the six corners of a regular octahedron.

Dimensions. — Diameter of all three rings 0'08, thickness 0'006.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

5. Trissocircus globus, n. sp. (PL 82, fig. 13).

All three rings equal, circular, thorny; their rods prismatic (in the transverse section triangular),
with three sharp dentated edges and scattered branched thorns. From each pole of the three equal
axes (which correspond to the three axes of a regular octahedron) arises a bunch of larger spines.

Dimensions. — Diameter of all three rings 012, thickness O'Ol.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 424. Trissocyclus,1 Haeckel, 1881, Prodromus, p. 446.

Definition. — Coronida with eight large, partly fenestrated gates of equal size.
Skeleton composed of three complete latticed rings, perpendicular to one another.

The genus Trissocyclus differs from its nearly allied ancestral form Trissocircus only
in the development of small anastomosing branches along the edges of the rings. The
incomplete lattice-work, produced by these anastomoses, partly protects the eight large
gates. The three rings are either of equal or of different sizes.

1 Trissocyclus = Composed of three crossed rings ;

REPORT ON THE RADIOLARIA. 987

Subgenus 1. Tricyclarium, Haeckel.

Definition. — Sagittal ring circular, smaller than the other two rings, which are both
elliptical.

1. Trissocychis stauroporus, n. sp. (PI. 83, fig. 5).

Sagittal ring circular, smaller than the other two equal elliptical rings. On each of the six
corners (or crossing points of every two rings) are developed four small pores, forming a cross
around the poles of the three axes. All three rings smooth, without spines.

Dimensions. — Height of the frontal ring 0'09, breadth 013.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Trissocychis triaxonius, n. sp.

Sagittal ring circular, smaller than the two other equal elliptical rings. From the edges of all
three rings are developed small branches, which by irregular ramification and anastomoses form
small irregular meshes along the rings. Similar to Trissocireus octostoma, but with thicker rings ;
it may be developed from the latter species by connection of the branches which border the rings.

Dimensions. — Height of the frontal ring 0'12, breadth 0'15.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

Subgenus 2. Tricyclonium, Haeckel.
Definition. — All three rings equal, circular.

3. Trissocyclus sphceridium, n. sp. (PL 93, fig. 12).

All three rings equal, circular, thorny ; their rods prismatic, three-sided, with three denticulate
edges ; the teeth of the lateral edges become branched, and form by anastomoses of the branches
small irregular meshes, which partly protect the eight large open gates.

Dimensions. — Diameter of the three rings 0'16, thickness 0'012.

Habitat. — Indian Ocean, Belligemma, Ceylon (Haeckel), surface.

Family LI. T Y M p A N I D A, Haeckel.

Parastephida, Haeckel, 1881, Prodromus, p. 446.

Definition. — S tephoidea with two parallel horizontal rings, an upper mitral and a
lower basal ring; both connected by complete or incomplete vertical rings, or by parallel
vertical columellse.

988 THE VOYAGE OF H.M.S. CHALLENGER.

The family Tympanida (or Parastephida) differs from the other Stephoidea
in the development of two horizontal rings, which lie in horizontal planes and arise from
the upper and the lower poles of the primary sagittal ring. Therefore the same formation,
which we found in the Semantida on the basal pole only of the main axis, here takes
place also on its apical pole. On both poles arise at each side from the sagittal ring two
corresponding pairs of curved branches : the lateral ends of the opposite branches (dorsal
and ventral branch) become united in the frontal plane and so form two complete
horizontal rings. The upper ring, composed of the superior or mitral branches, may be
called the mitral ring, the lower ring, formed by the inferior or basal branches, the basal
ring. Both rings are commonly of nearly equal size, more rarely of different sizes. Their
connection is effected either by the primary (sagittal) ring only, or also by secondary
vertical rings, a frontal ring in the lateral plane, or some diagonal meridian rings
between the latter and the former. These vertical rings, which connect both horizontal
rings in the form of " columellse," may be either complete or incomplete ; in the latter
case their apical and basal parts are lost, the dorsal and ventral parts only being
preserved.

The Tympanida develop a great variety of different forms, greater than in the three
other families of Stephoidea, so that we may distinguish here not less than sixteen
genera and seventy-two species. Hitherto only three species were known : Prismatium
tripleurum, figured in 1862 in my Monograph, Tympanidium barbadense, figured by Bury
in the "fossil Polycystins of Barbados," and Tympaniscus fibula, described in 1875
by Ehrenberg as a Ceratospyris fibula. The number of species in this large and richly
developed group will be considerably augmented by further researches. A great many of
them exhibit remarkable relations to different NASSELLABIA. For better survey of the
whole family we distinguish here four subfamilies, the first of which (Protympanida) is
probably the common ancestral group of the other three. They may have been derived
originally either from the Semantida or directly from the Stephanida.

The first subfamily, Protympanida, exhibits a complete primary or vertical sagittal
ring, bearing on the upper part a horizontal mitral ring, on the lower part a horizontal
basal ring. Therefore the gates of these two parallel rings become bisected by the
sagittal ring, each divided into a right and a left half. The sagittal ring itself becomes
divided by the two horizontal rings into four parts or rods ; two opposite of these are
more or less vertical ; the dorsal (posterior) and the ventral (anterior) rod ; the two
other rods are more or less horizontal ; the mitral (upper) and the basal (lower) rod.

In Protympanium (PL 93, fig. 14), the simplest and most primitive form of
Tympanida, the connection of the two horizontal rings is effected only by the dorsal and
ventral rods of the sagittal ring forming two parallel more or less vertical " columellse."
In all other Protympanida accessory columellee are developed between the latter. In the
greater number we find two secondary columellae in the lateral plane, being the lateral

REPORT ON THE RADIOLARIA. 989

segments of an incomplete frontal ring (Acrociibus, PL 93, figs. 15-17). Between the
latter and the former there are sometimes developed four tertiary columellse, as segments
of two crossed incomplete diagonal rings (Tympanidium, PI. 94, figs. 1, 18). At other
times we find six columellse ; here probably the frontal ring is cleft into halves on
each side (Tympaniscus, PI. 94, figs. 4-7). Some genera are distinguished by the
development of an equatorial ring, or a third horizontal ring (between the upper mitral
and the lower basal ring) ; this equatorial ring is either complete (Microcubus, PI. 94,
figs. 8-10) or incomplete, developed only laterally (Octotympanum, PI. 94, figs. 2, 3).
The genus Toxarium (PL 93, figs. 18-20) is distinguished by the development of
accessory pairs of bows in the frontal plane, upper or galear bows and lower or thoracal
bows, remarkable as beginnings of the accessory joints, which we distinguish in many
Spyroidea and Cyrtoidea as" galea and thorax."

The second subfamily of Tympanida are the Paratympanida, in which the two
horizontal rings become closed by lattice-work. The numerous columellse connecting
the two rings are here either divergent (Paratympanum, with two unequal rings, PL 94,
fig. 14) or parallel and vertical (Lithotympanum, with two equal rings, PL 83, fig. 1).
The shell of the latter assumes the form of a drum.

A third small subfamily, Dystympanida, is represented by a single genus only,
Dystympanium (PL 94, figs. 15, 16). Here only the upper or mitral ring is closed by
lattice-work, whilst the lower or basal ring exhibits a quite simple opening, a large
"basal gate" which has probably arisen by loss of the basilar rod of the sagittal ring.
These curious forms exhibit a remarkable resemblance to some Monocyrtida, and also to
the Dictyocha (PH^EODARIA).

The fourth subfamily, the Eutympanida, are distinguished by the simple wide
aperture of the two horizontal rings ; the upper enclosing a simple " mitral gate," the
lower a simple " basal gate." Here probably the two horizontal parts of the sagittal
ring (the upper mitral rod and the lower basilar rod) are lost by reduction ; its two
vertical parts (the dorsal and ventral rods) only remaining and forming the two parallel
columellse, which connect the two horizontal rings (Parastephanus, PL 93, fig. 21).
In this group also secondary columellse are commonly developed between the two rings,
alternating with the two primary columella3.- Pseudocubus (PL 94, figs. 11, 12),
resembling an obelisk, exhibits four divergent columellse ; the two sagittal of these are
probably the vertical parts of the primary ring, whilst the two lateral are the halves of an
incomplete frontal ring. In Lithocubus (PL 82, fig. 12) the four columellae are parallel
and vertical, the two rings being equal ; the shell here assumes the form of a geometrical
cube. Prismatium is distinguished by three parallel columellse ; two of these are probably
parts of a frontal ring, whilst the third is the remains of a reduced sagittal ring. In
Circotympamim (PL 94, fig. 17) and in Lithotympanum (PL 82, fig. 11) the number of the
eolurnellse is augmented, there being six to eight or more ; in the former they are divergent

990

THE VOYAGE OF H.M.S. CHALLENGER

(the two rings being of different sizes), in the latter parallel (the two rings being equal) ;
the fundamental form of the former is a truncated pyramid, of the latter a prism.

Comparing these differences between the four subfamilies of Tympanida, we may
suppose that the common ancestral group are the Protympanida, derived from the
Semantida by the formation of a mitral ring. If the two horizontal rings become closed
by lattice-work, the Paratympanida arise. When the mitral ring only becomes latticed,
the basal ring being simple, the Dystympanida originate. Finally, the fourth subfamily,
the Eutympanida, may be derived from the Protympanida by the loss of the two
horizontal parts of the sagittal ring.

The two horizontal rings (upper mitral and lower basal) and the two vertical rings
(primary sagittal and secondary frontal), which thus compose the loose framework of the
Tympanida, are rarely smooth, commonly armed with spines or branches, similar to those
of the Coronida. The rods or bars are either roundish (with circular transverse section)
or angular (commonly with triangular transverse section). The paired branches of the
two vertical rings often preserve the characteristic arrangement inherited from the
Semantida and Stephanida. The two horizontal rings sometimes exhibit typical
apophyses, which recur in the Spyroidea and C y r t o i d e a. The mitral ring may
possess one odd apical horn and two paired frontal horns (PL 93, figs. 16, 17, 19, 23).
The basal ring sometimes bears the three typical feet of Cortina (PI. 93, figs. 16, 22),
one odd caudal foot and two paired pectoral feet. Sometimes a fourth (sternal) foot is
developed (PI. 94, fig. 4), at other times only two lateral feet (PL 94, figs. 5, 6).

Synopsis of the Genera of Tympanida.

I. Subfamily

Protympanida.
Two horizontal rings
(upper mitral ring and
lower basal ring) bi-
sected by the complete
sagittal ring.

Two horizontal rings con- / One complete sagittal ring
nected by two columellae. \ (no frontal ring),

Two hori-
zontal rings
connected
by four
columellse
(the halves of
the sagittal

and the
frontal ring).

No equa-
torial rinse.

An equa-
torial ring.

No galear and thoracal
bows,

Galear and thoracal bows, .
Equatorial ring complete,
Equatorial ring incomplete,

II. Subfamily

Paratympanida.
Two horizontal rings
fenestrated.

Two horizontal rings con- \ Six cohimell* (three rneri-
nected by six or eight 1 dlonal rmS8)' '
columellae (three or four 1 -^. , , , ,,
vertical rings). ElSht ****&• (fonr men-

[_ dional rings),

Two horizontal rings closed
J by a lattice-plate, con- J

Two .F™^ unequal (cola-
mellse dl™rgent),

nected by
columellfe.

numerous

I Two rings equal (columelhe
[ parallel),

425. Protympanium.

426. Acrocubus.

427. Toxarium.

428. Microculms.

429. Odotympanum.

430. Tympaniscus.

431. Tympanidium.

432. Paratympanum.

433. Litlwtympanum.

REPORT ON THE RADIOLARIA.

991

III. Subfamily

Dystympanida.
Mitral ring fenestrated,
basal ring simple.

IV. Subfamily

Eutympanida.

Two horizontal rings
(upper mitral ring and
lower basal ring)
simple. Apical and
basal parts of the
sagittal ring lost.

Two horizontal rings con-
nected by numerous (six
to eight or more colu-
mellse).

Two horizontal rings con-
nected by two or three
columellae (four or five
open gates).

Two horizontal rings con-
nected by four or more
columellse (six or eight or
more open gates).

Mitral ring closed by a lat-
tice-plate, basal ring
simple, .

Two columellse (parts of the
sagittal ring), .

Three columellse (parts of
the half sagittal and the
frontal ring),

Four colu-
mellse.

Two rings
unequal,

Two rings
equal, .

f Two rings

Six to eight | unequal,

or more

columellse. 1 Two rings
equal, .

434. Dystympanium.

435. Parastephanus.

436. Prismatium.

437. Pseudocubus,

438. Lithocubm.

439. Circotympanum.

440. Eutympanium.

Subfamily 1. PROTYMPANIDA, Haeckel.

Definition. — T ympanida with two bisected horizontal rings, connected by the
complete vertical sagittal ring. (The upper mitral ring and the lower basal ring become
divided by the complete primary or sagittal ring into two horizontal symmetrical gates,
two mitral gates on the apical and two basal gates on the basal pole.)

Genus 425. Protympanium,1 Haeckel, 1881, Prodromus, p. 447 (sensu emend.}.

Definition. — T ympanida with two bisected horizontal rings, connected by two
vertical columellse.

The genus Protympanium is the most simple form of all Tympanida, and probably
the common ancestral form of this family. It arises from Lithocircus by the develop-
ment of two horizontal rings, perpendicular to the primary sagittal ring. The upper or
mitral ring arises by lateral union of two pairs of superior branches, the lower or basal
ring by union of two pairs of basal branches of the primary vertical ring.

1. Protympanium primordiale, n. sp.

Mitral and apical ring of equal size, elliptical, smooth, somewhat smaller than the connecting
thorny sagittal ring.

Dimensions. — Diameter of the two horizontal rings 0'12, of the sagittal ring 015.
Habitat. — Central Pacific, Stations 263 to 274, at various depths.

1 Protympanium = Primordial drum;

992 THE VOYAGE OF H.M.S. CHALLENGEE.

2. Protympanium amphipodium, n. sp. (PI. 93, fig. 14).

Mitral and apical rings of equal size, thin, elliptical, smooth, larger than the broad connecting
sagittal ring. The latter bears on the apical and on the basal pole two divergent straight spines
(lying in the frontal plane), the two apical (or horns) somewhat smaller and not so spiny as the
two basal spines (or feet). In the frontal plane there arise from the two horizontal rings on each
side two small opposite spines (remnants or beginnings of the lateral frontal ring ?).

Dimensions. — Diameter of the two horizontal rings O'll, of the sagittal ring O'OT.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Protympanium trissocircus, n. sp.

Mitral ring smaller than the basal ring ; both rings circular, rough. Sagittal ring in size
between the two former. All three rings covered with very small thorns.

Dimensions. — Diameter of the mitral ring 0'08, of the sagittal ring O'l, of the basal ring 0'12.
Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 426. Acrocubus?- Haeckel, 1881, Prodromus, p. 447.

Definition. — Tympanida with two bisected horizontal rings, connected by four
vertical columellse. No equatorial ring.

The genus Acrocubus is the most primitive of those remarkable Tympanida, the
skeleton of which represents more or less exactly the form of a geometrical cube. A
simple complete sagittal ring bears on the superior and on the inferior part two opposite
pairs of lateral branches ; by union of the convergent branches of each side there arise two
horizontal parallel quadrangular rings, which are bisected by the sagittal ring. There-
fore the superior ring encloses two triangular mitral gates, the inferior two triangular
basal gates. The lateral corners of the two gates of each side are connected by a
vertical rod or columella. These two parallel columellse are the remaining middle parts
of the secondary or frontal ring, which is incomplete on the superior and on the inferior
face of the body. If the sagittal ring also become incomplete, by the loss of the
superior and inferior part (the anterior and posterior only remaining), then Acrocubus is
transformed into Lithocubus.

Subgenus 1. Apocubus, Haeckel.
Definition. — Basal ring without descending feet.

1 Acrocubus= Perfect cube ; a.x^, xD/3oj.

REPORT ON THE RADIOLARIA. 993

1. Acrocubus octopylus, n. sp. (PI. 82, fig. 9).

Mitral ring somewhat smaller than the basal ring ; both rings rhombic, with curved outlines.
Sagittal ring elliptical, with six pairs of nodulate protuberances. Four columellse curved. Nodal
points without radial spines.

Dimensions. — Height of the frontal ring 012, breadth 018.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Acrocubus tesseralis, n. sp.

Mitral ring of the same size as the basal ring ; both rings square, smooth, with straight
outlines. Sagittal ring also square, smooth. Four columellse straight. Nodal points without
radial spines. The shell has the form of a regular geometrical cube, the edges of which are
represented by the rings.

Dimensions. — Height of the frontal ring 01, breadth Oil.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

Subgenus 2. Dipocubus, Haeckel.
Definition. — Basal ring with two descending feet.

3. Acrocubus brachiatus, n. sp.

Mitral ring smaller than the basal, both rings square, with thick straight rods. Sagittal ring
tuberculate, square, equatorial part thinner. Four columellae curved, the two lateral ones prolonged
downwards into two vertical parallel straight feet of half their length.

Dimensions. — Diameter of the cube 012 ; length of the feet 0'06.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Acrocubus amphistylus, n. sp.

Mitral and basal rings of nearly equal size, square, with thick curved rods. Sagittal ring
elliptical, in the equatorial part thinner. Frontal ring tuberculate. Four columellse curved, the
two lateral ones prolonged downwards into two vertical, tuberculate feet of half their length.

Dimensions. — Diameter of the cube 013 ; length of the feet O'OV.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

5. Acrocubus arcuatus, n. sp. (PI. 93, fig. 15).

Mitral and basal rings, as well as the sagittal ring, of the same form as in the preceding nearly
allied species. The two lateral columellffi are prolonged not only downwards into two short
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Kr 125

994 THE VOYAGE OF H.M.S. CHALLENGER.

vertical feet, but also upwards into two curved bows, which are united in a vertical ascending
horn, arising from the apical pole of the sagittal ring.

Dimensions. — Diameter of the cube 014 ; total height 0'21.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Subgenus 3. Tripocubus, Haeckel.

Definition. — Basal ring with three descending feet (one odd caudal and two
paired lateral).

6. Acrocubus lasanum, n. sp.

•

Mitral ring smaller than the basal, both rings square, with curved rods. Sagittal ring ovate,
prolonged upwards into an occipital simple horn, downwards into a caudal foot. Two lateral
columellse prolonged downwards into two pectoral feet. All three feet conical, about as long as
the height of the cube.

Dimensions. — Diameter of the cube 0'08 ; length of the feet 0'07.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

7. Acrocubus cortina, n. sp. (PI. 93, fig. 16),

Mitral ring smaller than the basal, both rings elliptical, with curved rods. Sagittal ring
ovate, prolonged upwards into an occipital horn, downwards into a caudal foot, as in,the preceding
species. As in the latter, also, the two lateral columellse are prolonged downwards into two
pectoral feet, but also upwards into two convergent horns, which are united with the occipital
horn (commencing the formation of a galea). Rings and feet somewhat thorny.

Dimensions. — Diameter of the cube 016 ; total height 0'2.

Habitat.- — Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 4. Tetracubus, Haeckel.
Definition. — Basal ring with four descending feet (two sagittal and two lateral).

8. Acrocubus tetrapodius, n. sp.

Mitral and basal rings of the same size, square, with straight rods, sagittal ring also square.
The four vertical columellse are nearly parallel and straight, prolonged upwards into four short
conical horns, downwards into four longer conical feet (The shell has nearly the form of a
geometrical cube, the eight corners of which are prolonged into eight vertical conical spines,
four smaller ascending and four larger descending.)

Dimensions. — Diameter of the cube 0'09 ; length of the feet 0'06.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

REPORT ON THE RADIOLARIA. .995

9. Acrocubus amphithectus, n. sp. (PI. 93, fig. 17).

Mitral ring smaller than the basal, both rings elliptical, with curved rods. Four coluraellae
thorny, also curved, divergent downwards, prolonged upwards into four thorny convergent horns,
downwards into four larger branched divergent feet. The two sagittal horns and feet (anterior
and posterior) are smaller than the two lateral (right and left) ; therefore the fundamental form
of this species is distinctly amphithect (as in the Ctenophora).

Dimensions. — Breadth of the cube 012 ; total height 0-2.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

Genus 427. Toxarium,1 n. gen.

A

Definition. — T.y m p a n i d a with two bisected horizontal rings, connected by four
vertical columellse. In the frontal plane two galear bows project upwards, and two
thoracal bows downwards.

The genus Toxarium differs from its ancestral form Acrocubus in the development
of two pairs of peculiar bows, placed in the lateral or frontal plane ; the upper pair
projects above the mitral gates, and may be called the " galear "bows," the lower pair
projects below the basal gates of the cubical shell, and may be called the " thoracal
bows." Both pairs are produced originally by the development of two forked vertical
spines, arising in the frontal plane on both poles of the principal axis from the sagittal
ring (compare Protympanium amphipodium, PL 93, fig. 14). The apical fork-
branches become connected with the lateral corners of the mitral gates, the basal
.branches with those of the basal gates. By development of lattice-work between the
bows and the rings some Spyroidea (Amphispyris, &c.) may have arisen. The
important genus Toxarium may be divided into three subgenera. In Toxellium all
the bows are simple, in Toxonium all are forked ; in Toxidium the galear bows are
simple, the thoracal bows forked.

Subgenus 1. Toxellium, Haeckel.
Definition. — Galear and thoracal bows simple.

1. Toxarium circospyris, n. sp. (PI. 88, fig. 1).

Galear and thoracal bows simple, of about the same size as the frontal bows between them ; all
bows armed with scattered simple conical spines. Sagittal constriction deep, half as long as the
whole shell. Lateral outlines of the shell nearly parallel.

Dimensions. — Length of the shell 0-16, breadth 0'13.

Habitat. — Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

1 Toxarium — Small bow ; T

996 THE VOYAGE OF H.M.S. CHALLENGER,

2. Toxarium svbcirculare, n. sp.

Galear and thoracal bows simple, armed with scattered simple spines, of about equal size,
smaller than the smooth frontal bows between them. Sagittal constriction very flat. Therefore
the frontal perimeter of the shell is nearly circular.

Dimensions. — Length of the shell 015, breadth 014.

Habitat. — North Atlantic (Antilles), "Weber, surface.

3. Toxarium thorax, n, sp. (PL 93, fig. 18).

Galear bows simple, smaller than the frontal bows, and these again smaller than the simple
thoracal bows ; therefore the shell increases in breadth towards the base, and resembles the skeleton
of the thorax of one of the higher vertebrates (the bow-pairs corresponding to rib-pairs, the ventral
part of the sagittal ring to the sternum, the dorsal part to the vertebral column). Sagittal
constriction very deep. All bows are armed with scattered, irregularly branched spines.

Dimensions. — Length of the shell 017, breadth 0'2.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Toxarium constrict'um, n. sp,

Galear and thoracal bows simple, of nearly equal size, larger than the 'frontal bows between
them. Therefore the shell is constricted in the equatorial plane. Sagittal constriction also deep.
All bows armed with scattered, irregularly branched spines.

Dimensions. — Length of the shell 014, breadth 012.

Habitat. — North Pacific, Station 236, surface.

Subgenus 2. Toxidium, HaeckeL
Definition. — Galear bows simple, thoracal bows forked,

5. Toxarium cordatum, n. sp. (PI. 93, fig. 19).

Galear bows simple, thoracal bows forked, both somewhat smaller than frontal bows ; all bows
armed with scattered simple conical spines, mostly developed at the thoracal bows. Both galear
bows are united in a central vertical columella, which arises from the apex of the sagittal ring, and
is prolonged into an apical horn. Therefore the sagittal constriction exists only in the basal half of
the inversely cordate shell.

Dimensions. — Length of the shell 018, breadth 016.

Habitat. — South Atlantic, Station 348, depth 2450 fathoms.

REPORT ON THE RADIOLARIA. 997

6. Toxarium furcatum, n. sp,

Galear bows simple, thoracal bows forked, both somewhat broader than the frontal bows.
Shell therefore slightly constricted in the equatorial plane. Sagittal constriction rather deep, equal
in the apical and basal parts. All bows armed with scattered spines, which are partly simple, partly
forked.

Dimensions. — Length of the shell 014, breadth 016.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms..

7. Toxarium pedatum, n. sp.

Galear bows simple, smaller than the frontal bows, which are again smaller than the thoracal
bows. Therefore the breadth of the shell increases towards the base. Sagittal constriction flat in
the apical part, deep in the basal part. All bows armed with small irregularly scattered spines ;
at the base six larger divergent feet (two lateral, two anterior, and two posterior).

Dimensions. — Length of the shell 017, breadth 015.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

Subgenus 3. Toxonium, Haeckel.
Definition. — Galear and thoracal bows forked.

8. Toxarium costatum, n. sp.

Galear and thoracal bows forked, smaller than the frontal bows, all bows thorny, without larger
spines. Sagittal constriction on both poles deep. Lateral outlines of the shell nearly parallel.
Dimensions. — Length of the shell 015, breadth 012.
Habitat. — Indian Ocean, Socotra (Haeckel), surface.

9. Toxarium bifurcum, n. sp. (PI. 93, fig. 20).

Galear and thoracal bows forked, the former smaller than the frontal bows, the latter larger.
Sagittal constriction rather flat on the apical pole, which bears a vertical forked horn, very deep on
the basal pole of the primary ring. All bows armed with numerous spines, which are partly
simple, partly forked, and mainly developed at the basal part of the thoracal bows.

Dimensions. — Length of the shell 0'2, breadth 0'2.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 428. Microcubus,1 Haeckel, 1881, Prodromus, p. 447.

Definition. — T ympanida with two bisected horizontal rings, connected by four
vertical columellse, which are bisected again by an equatorial ring.

1 Microcubus = Small cube ; ft.ix.fa, xS/So? .

998 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Microcubus is derived from its ancestral form Acrocubus by develop-
ment of a third horizontal ring, which lies in the equatorial plane, parallel to the upper
mitral and the lower basal ring. Whilst these latter are both bisected by the complete
vertical sagittal ring, the equatorial ring is complete, and connected at the poles of the
sagittal axis with the principal ring, and at the poles of the transverse axis with the frontal
ring. Therefore the shell exhibits not eight large gates as in Acrocubus, but twelve,
viz., four horizontal gates (two superior mitral and two inferior basal), four upper
vertical gates (between the mitral and the equatorial ring), and four lower vertical gates
(between the basal and the equatorial ring).

1. Microcubus dodecastoma, n. sp. (PI. 94, fig. 9).

All twelve gates simple, irregularly ovate or pentagonal. Frontal ring 011 the sides concave,
constricted by the equatorial ring. All rings curved, armed with short irregular thorns. No larger
basal spines.

Dimensions. — Length of the shell 0'13, breadth 0'15.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

2. Microcubus pentacircus, n. sp.

All twelve gates simple. Frontal ring on the sides convex, not constricted by the equatorial
ring. All rings tuberculate, with irregular roundish knots. No larger basal spines. Similar to
the preceding species ; but the five rings are much thicker and tuberculate (not thorny) ; the
twelve gates are therefore relatively smaller.

Dimensions. — Length of the shell O'l, breadth 0'12.

Habitat. — Fossil in Barbados.

3. Microcubus zonarius, n. sp. (PI. 94, fig. 8).

All twelve gates simple, ovate. Frontal ring on the sides convex, not constricted by the
equatorial ring, nearly twice as broad as long. All rings thorny, very thin, except only the
broad angular sagittal ring. No larger basal spines.

Dimensions. — Length of the shell 0'08, breadth 0'15.

Habitat. — Central Pacific, Station 271, depth' 2425 fathoms,

4. Microcubus quadrupes, n. sp.

All twelve gates simple, square. Frontal ring square, not constricted by the equatorial ring.
All rings smooth, quadrangular. Basal ring with four short vertical conical feet, two of which
(right and left) are inferior prolongations of the frontal ring, and arise from the lateral corners of the

REPORT ON THE RADIOLARIA. 999

basal gates ; two others are prolongations of the sagittal ring (sternal and caudal), and arise from the
medial corners of the basal gates. (The shell is like a small cube with four feet.)

Dimensions. — Length of the shell 013, breadth Oil.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

5. Microcubus cornutus, n. sp.

Eight gates (two mitral, two basal, and four superior) simple ; four inferior gates fenestrated by
arachuoidal irregular threads. Frontal ring square, constricted on the sides by the equatorial ring.
Basal ring with four short conical vertical feet, as in the preceding species. Sagittal ring with a
vertical horn on the apex. All rings with small scattered thorns.

Dimensions. — Length of the shell Oil, breadth 013,

Habitat. — North Pacific, Station 235, surface.

6. Microcubus amphispyris, n. sp. (PL 94, fig. 10).

Four gates (two mitral and two basal) simple ; eight lateral gates (four superior and four
inferior) fenestrated by arachnoidal irregular threads. Frontal ring convex, not constricted by the
equatorial ring. Basal ring with six short conical divergent feet (two sagittal and four lateral).
Sagittal ring with an apical horn. (Resembles some Spyroidea.)

Dimensions. — Length of the shell 0'08, breadth 012.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 429. Octotympanum? n. gen.

Definition. — T ympanida with two bisected horizontal rings converging laterally
and connected in the lateral poles of the equatorial plane. Eight large gates.

The genus Octotympanum differs from all other Tympanida in the peculiar connection
of the two horizontal rings, which here reach the maximum of their growth, converge
.towards the equator, and come into direct contact on the poles of the equatorial trans-
verse axis. Therefore the shell appears to be composed of three complete vertical
meridian rings, the middle of which (the sagittal ring) is free and simple ; the two
other (subfrontal) rings are grown together at the lateral poles of the equatorial plane ;
commonly at these poles there arises (on the right and left) a strong lateral spine, and
the base of this (or the crossing point of the two touching horizontal rings) corresponds
to the remnants of the shortened frontal ring. The crown-shaped shell exhibits there-
fore eight large gates ; two superior (mitral) and two inferior basal gates, two larger
anterior (facial) and two larger posterior (occipital) gates. Seen from the 'lateral poles

1 Octotympanum = Drum with eight gates; oma, rvf

1000 THE VOYAGE OF H.M.S. CHALLENGER.

only two of the former are visible, and represent the figure of a vertical 8 ; seen from
the sagittal poles, only two of the latter are visible, in the form of a larger horizontal oo .
Octotympanum may be derived from Acrocubus by reduction of the lateral frontal ring
to a knot (or cross-point), and by maximal extension of the two parallel horizontal rings,
which become curved downwards laterally and touch at the lateral poles.

1. Octotympanum octospinum, n. sp.

Mitral gates smaller than the basal gates ; upper halves of the two lateral meridional rings
smaller than the lower halves. Eings with few scattered thorns ; four larger simple spines, nearly
horizontal in the equatorial plane ; two on the poles of the sagittal axis, two on the poles of the
lateral axis. Four other large spines, nearly vertical at the four lowermost basal points of the sub-
frontal rings.

Dimensions. — Length of the shell 0'09, breadth 012.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

2. Octotympanum octonarium, n. sp. (PI. 94, fig. 3).

Mitral gates of the same size as the basal gates ; upper and lower halves of the meridional rings
of equal size. Eings armed with numerous stout, thorny, simple and forked spines ; four very large
branched spines in the equatorial plane, nearly horizontal, two on the poles of the sagittal, two on
the poles of the transverse axis, the latter curved downwards.

Dimensions. — Length of the shell 01, breadth 0-2.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Octotympanum arborescens, n. sp.

Mitral gates smaller than the basal gates, the lower halves of the lateral rings being broader
than the upper halves. Eings very spiny, armed with numerous branched spines ; ten very large
arborescent spines on the lateral rings ; two on the poles of the transverse axis, eight on the pro-
minent corners of the diagonal axes (four upper and four lower) ; sagittal ring thorny.

Dimensions. — Length of the shell 0'8, breadth 016.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

4. Octotympanum cervicorne, n. sp. (PI. 94, fig. 2).

Mitral and basal gates of equal size, the lower and upper halves of the two crossed lateral rings
being nearly equal. Eings armed with numerous branched spines ; two very large spines, similar
to the antlers of a deer, on the poles of the lateral axis ; their branches about half as large as the
whole shell. Sagittal ring nearly smooth, with few small thorns on the poles of the main axis.

Dimensions. — Length of the shell 016, breadth 0'2.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms

REPORT ON THE RADIOLARIA. 1001

Genus 430. Tympaniscus,1 n. gen.

Definition. — T ympanida with two bisected horizontal rings, which are connected
by three vertical meridional rings (or six columellae).

The genus Tympaniscus and the following Tympanidium differ from all preceding
Tympanida in the multiplication of the vertical columellse, which connect the two
horizontal bisected rings. Tympaniscus exhibits six columellae, which may be regarded
as halves of three meridional rings. Only one, however, of these is complete (the sagittal
ring, which bisects the mitral and the basal ring) ; the two other meridional rings (placed
in diagonal planes) may be regarded as produced by lateral bifurcation of an incomplete
frontal ring ; this appears to be already foreshadowed in the preceding Octotympanum.

I. Tympaniscus corona, n. sp.

Basal ring larger than the mitral ring, with numerous irregular short spines but without
descending feet. Six columella? strongly curved, in the lower half thicker and thorny ; the four
lateral much thinner than the two sagittal. Apex of the jointed sagittal ring with a conical horn.

Dimensions. — Length of the shell 0'08, breadth Oil.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Tympaniscus bipes, n. sp.

Basal ring of about the same size as the mitral ring, with two lateral descending feet, which
are parallel and vertical, simple, without spur, half as long as the sagittal ring. The latter is ovate,
twice as long and broad as the two circular frontal rings.

Dimensions. — Breadth of the shell 0'14, length 0'09.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

3. Tympaniscus dipodiscus, n. sp. (PL 94, figs. 5, 6).

Basal ring smaller than the mitral ring, with two lateral descending feet, which are nearly
parallel and vertical, obtuse, about as long as the sagittal ring, and which bear on the outside a
horizontal spur. Sagittal ring hexagonal, very stout, with a caudal appendix at the base, and with a
small sagittal arch, bearing a stout spinulate double knob at the apex. The two subfrontal rings
depressed, twice as broad as high, on the outside thorny, connected at each side in the lower half
by a double transverse arch.

Dimensions. — Breadth of the shell 018, length 0'08 (with spines 018).

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

1 Tympaniscus = Little drum; -rv/tirctnlijxtt;.
(ZOOL. CHALL. BXP. — PART XL. — 1886.) Rr 126

1002 THE VOYAGE OF H.M.S. CHALLENGER.

4. Tympaniscus tripodiscus, n. sp. (PI. 94, fig. 7).

Basal ring of about the same size as the mitral ring, with three large and stout divergent feet
(two lateral and one caudal). Sagittal ring stout, broader than the two spiny subsagittal rings ;
the upper part of the latter bears two ascending arches, which are united with the large apical horn
arising from the apex of the sagittal ring. Six columellaa nearly vertical, slightly curved on the
outside ; their lateral edges armed with numerous simple or forked spines.

Dimensions. — Breadth of the shell Ol, total length 0'12.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

5. Tympaniscus quadrupes, n. sp. (PI. 94, fig. 4).

Basal ring larger than the mitral ring, with four short vertical three-sided pyramidal feet of
equal size (two lateral and two sagittal) ; the feet are three-sided pyramidal, with finely denticulate
median edges, and bear at the base a horizontal thorny spur. Sagittal ring at the apex with a very
large cross-shaped horn, bearing two horizontal thorny lateral branches ; the horn is supported by
an anterior and a posterior arch. Six columellae strongly curved and dentate.

Dimensions. — Breadth of the shell 0415, length 012.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

6. Tympaniscus fibula, Haeckel.

Ceratospyris fibula, Ehrenherg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.
fig. 3.

Basal ring of about the same size as the mitral ring, with six large conical descending feet;
these, are prolongations of the six columellse, nearly of the same length, slightly divergent, and bear
at the base a strong horizontal spur. The six columellae are strongly curved, spiny, and bear above
small arches, which are united with the apical horn of the sagittal ring.

Dimensions. — Breadth of the shell 0'09, height 0'05 ; total height 009.

Habitat. — Fossil in Barbados.

7. Tympaniscus dodecaster, n. sp.

Basal ring of the same size as the mitral ring, with six very large and six alternating smaller,
slightly divergent, curved feet, about as long as the shell ; the larger are the basal prolongations
of the six curved, thorny columellse. Mitral ring spiny, not overgrown with arches, as in the
similar preceding species.

Dimensions. — Length of the shell 0'08, breadth 012.

HaUtat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

REPORT ON THE RADIOLARIA. 1003

Geuus 431. Tympanidium,1 Haeckel, 1881, Prodromus, p. 447.

Definition. — T ympanida with two bisected horizontal rings, which are
connected by four vertical meridional rings (or eight columellse).

The genus Tympanidium differs from all other Protympanida in the development
of four vertical rings, placed in four different meridional planes. Only one of these is
complete, the primary sagittal ring ; the three others are incomplete, inserted on the
two horizontal rings, which are formed by the paired mitral and basal branches of the
sagittal ring ; one of these three lies in the frontal plane, the two others in diagonal
meridional planes (between the frontal and sagittal). The shell therefore exhibits
twelve large gates, four of which are horizontal (the two superior mitral and the two
inferior basal gates) ; the eight others are vertical, separated by the eight columellse,
or the halves of the four meridional rings. In the subgenus Tympanomma the number
of gates amounts to sixteen, the four lateral gates being bisected by an incomplete
equatorial ring. The genus Tympanidium may be derived from Acrocubus by
development of the two diagonal rings (between the frontal and sagittal).

Subgenus 1. Tympanura, Haeckel.
Definition. — Shell with twelve gates ; the four lateral gates simple.

1. Tympanidium foliosum, n. sp. (PL 94, fig. 1).

Shell with twelve gates ; the four lateral gates simple. Basal gates of the shell larger than
the mitral gates. Sagittal ring ovate, much smaller than the three other meridional rings, which are
armed with numerous large elegant spines, bearing a lanceolate leaf on a thin pedicle. The
sagittal ring bears a bunch of similar spines only at the apex, and on both poles of the sagittal
axis (in the equator) a single forked spine, with two thorny branches.

Dimensions. — Length of the shell 0'09 (with spines 0'25), breadth 0'15.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

2. Tympanidium spinosum, n. sp.

Shell with twelve gates ; the four lateral gates simple. Basal and mitral gates of about equal
size. Shell similar to that of the preceding species, differing mainly in the different armature ; the
numerous spines, covering the convex outside of the four vertical rings, are not leaf-shaped, but
conical, short, of very variable size, partly simple, partly irregularly branched.

Dimensions.- — Length of the shell 0'08 (with spines 0'2), breadth 012.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

1 Tympanidium = Small drum ; tv^xiii^iaii.

1004 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 2. Tympanomma, Haeckel.

Definition. — Shell with sixteen gates (eight median gates, paired on both sides of
the sagittal ring, and eight lateral gates, paired on both sides of the frontal ring).
The four lateral gates of the two preceding species (subgenus Tympanura) are bisected
in Tympanomma by the lateral parts of an incomplete equatorial ring.

3. Tympanidium binoctonum, n. sp. (PL 94, fig. 18).

Shell with sixteen gates ; the four lateral gates double, bisected by the lateral parts of
an incomplete equatorial ring. Basal gates nearly rectangular, of the same breadth as the
pentagonal mitral gates, but twice as long. Equatorial outline of the shell (seen in fig. 18 from the
apical pole) octagonal. All rods of the shell thin, smooth.

Dimensions. — Transverse axis of the shell 01, sagittal axis 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

4. Tympanidium barbadense, Haeckel.

"Hollow cylinder," &c., Bury, 1862, Polycystius of Barbados, pi. xvi. fig. 1.

Shell with sixteen gates ; the four lateral gates double, bisected by an incomplete equatorial
ring. Basal gates kidney-shaped, of the same breadth as the circular mitral gates, but twice
as long. Equatorial outline of the shell elliptical. All rods of the shell thin, smooth.

Dimensions. — Transverse axis of the shell 0'12, sagittal axis O08.

Habitat. — Fossil in South Naparima, Trinidad, Barbados.

5. Tympanidium staurocircum, n. sp.

Shell with sixteen gates ; the four lateral gates double, bisected by an incomplete equatorial
ring. Basal and mitral gates of the shell of about equal size, roundish. Equatorial outline of
the shell violin-shaped, with a sagittal constriction. All rods of the shell armed with short
irregular spines.

Dimensions. — Transverse axis of the shell 012, sagittal axis 0'06.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Subfamily 2. PARATYMPANIDA, Haeckel, 1881, Prodromus, p. 447.

Definition. — T y m p a n i d a with two fenestrated horizontal rings, which are
connected by a variable number of vertical rods or columellse. The shell therefore
becomes more completely latticed than in the other Tympanida, and approaches that of
the Spyroidea.

REPORT ON THE RADIOLARIA. 1005

Genus 432. Paratympanum,1 Haeckel, 1881, Prodromus, p. 447.

Definition. — T ympanida with two latticed horizontal rings, connected by
numerous descending and diverging columellse ; mitral ring smaller than the basal ring.

The genus Paratympanum and the following nearly allied Lithotympanum form
together the small subfamily of Paratympanida, distinguished from the other Tympanida
by the fenestration of the two parallel horizontal rings. These rings in Lithotympanum
are both equal, whilst in Paratympanum the basal ring is larger than the mitral
ring ; therefore the connecting rods or columellse are in the former parallel and vertical,
in the latter divergent and descending. Two opposite ones of these columellse are parts
of the primary sagittal ring, two others are parts of the lateral or frontal ring, whilst the
remainder are afterwards intercalated. Paratympanum may be derived from Dystym-
panium by fenestration of the basal ring.

1. Paratympanum hexastylum, n. sp.

Six divergent columellse, about as long as the diameter of the hexagonal mitral ring, connect it
with the larger hexagonal basal ring. Lattice of the mitral ring hemispherical, with six roundish
pores, surrounding a central apical horn. Lattice of the basal ring with one large central pore,
surrounded by numerous peripheral pores. Eings and rods smooth, without spines.

Dimensions. — Length of the shell 0'07 ; breadth of the mitral ring 0'06, of the basal ring 0'09.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Paratympanum octostylum, n. sp. (PI. 94, fig. 14).

Eight divergent columellte, about as long as the diameter of the octagonal mitral ring, connect
it with the larger circular basal ring, and bear at each end a divergent, strong, conical spine.
Lattice-plate of both rings slightly convex, with numerous subregular circular pores, smooth,
without surface spines.

Dimensions. — Breadth of the mitral ring 0-06, of the basal ring 0'09.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Paratympanum decastylum, n. sp.

Ten divergent columellae, only half as long as the diameter of the decagonal mitral ring,
connect it with the larger circular basal ring. Lattice-plate of the mitral ring nearly hemispherical
of the basal ring flat, both with numerous irregular roundish pores and scattered spines. Margin
of both rings spiny.

Dimensions. — Breadth of the mitral ring 0'08, of the basal ring O'l.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

1 Paratympanum = Side-drum ; •x-a^ci, Tvpirxutni.

1006 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 433. Lithotympanum,1 Haeckel, 1881, Prodromus, p. 447.

ffefinition. — T ympanida with two latticed horizontal rings, connected by
numerous parallel and vertical columellse ; mitral and basal rings of equal size.

The genus Lithotympanum has the form of a cylindrical drum, the two fundamental
faces of which (the mitral and basal gates) are closed by lattice-work. Both horizontal
rings are equal, whilst in the preceding Paratympanum the basal gate is larger than
the mitral. It may be derived from the latter by equalisation of these two rings, or
directly from Dystympanium by fenestration of the basal ring.

1. Lithotympanum tuberosum, n. sp. (PI. 83, fig. 1).

Both lattice-plates slightly convex ; the mitral plate with six larger marginal pores and one
central pore separated by numerous smaller pores ; the basal plate with seven large pores only (one
central and six peripheral). Surface and margin of the plates uneven, with roundish prominent
dimpled tubercles. Both rings connected by ten to twelve simple cylindrical vertical columellae.

Dimensions. — Length of the shell 013, breadth 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Lithotympanum spinosum, n. sp.

Both lattice-plates flat, with numerous irregular roundish pores of variable size. Surface
thorny. Margin with numerous irregular spines, directed upwards on the mitral, downwards on
the basal plate. Both rings connected by eight simple cylindrical vertical columellae.

Dimensions. — Length of the shell 0'12, breadth 0'08.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

Subfamily 3. DYSTYMPANIDA, Haeckel.

*

Definition. — T ympanida with fenestrated mitral ring and simple open basal ring ;
both horizontal rings connected by numerous vertical or divergent columellse.

Genus 434. Dystympanium,'2 n. gen.

Definition. — Tympanida with two horizontal rings, connected by numerous (six
to eight or more) divergent columellse. The upper mitral ring is smaller and latticed,
the lower basal ring larger and open.

1 Lithotympanum — Drum of silex; A/dof, •cvfvrxnov. 2 Dystympanium = Hideous drum ; Si/j, TvftK»iiiw.

REPORT ON THE RADIOLARIA. 1007

The genus Dystympanium, representing a peculiar subfamily, differs from all other
Tympanida in the different shape of the two parallel horizontal rings. The upper or
mitral ring is closed by a lattice-plate (as in Paratympanum), the lower or basal ring is
simple and open (as in Eutympanium). Dystympanium may therefore be regarded as
an intermediate form between these two genera, and may perhaps be derived from
Paratympanum by loss of the lower lattice-plate.

1. Dystympanium dictyocha, n. sp. (PI. 94, figs. 15, 16).

Basal ring circular, with eighteen to twenty short conical divergent spines. Mitral ring about
two-thirds as broad, hexagonal, with six ascending spines on the six corners. The latter are
connected with the former by six simple, straight, obliquely descending columellse, about as long as
the diameter of the mitral ring. Mitral lattice-plate slightly convex, with seven roundish pores
(six peripheral pores around a central pore).

Dimensions. — Diameter of the basal ring 0'09, mitral ring 0'06 ; length of the columellse 0'05.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

2. Dystympanium distephanus, n. sp.

Basal ring hexagonal, with six larger spines at the six corners, and numerous smaller ones between
them. Mitral ring half as broad as the basal ring, also with six angular spines. The latter are
connected with the former by six divergent curved columellse, about as long as the diameter of the
basal ring. Mitral lattice-plate flat, with irregular roundish pores.

Dimensions. — Diameter of the basal ring O'l, mitral ring O'Oo ; length of the columellse 0'09.

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

3. Dystympanium medusa, n. sp.

Basal ring circular, with eight larger and numerous smaller divergent spines. Mitral ring two-
thirds as broad as the basal ring, octagonal, with eight conical ascending spines on the eight corners.
The latter are connected with the former by eight divergent, curved columelke, as long as the
diameter of the mitral ring. Mitral lattice-plate nearly hemispherical, with nine circular pores
(eight peripheral pores around one central pore).

Dimensions. — Diameter of the basal ring 012, mitral ring 0'08 ; length of the columellse 0'09.

Habitat. — South Atlantic, Station 332, 'depth 2200 fathoms.

Subfamily 4. EUTYMPANIDA, Haeckel.

Definition. — T y m p a n i d a with two simple horizontal rings, which are connected
by a variable number of vertical rods or columellse. Therefore the shell exhibits a large
simple mitral gate on the upper, and a large simple basal gate on the lower side; between
the two a variable number of lateral gates.

1008 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 435. Parastephanus, Haeckel, 1881, Prodromus, p. 446.

Definition. — Ty m pan id a with two simple horizontal rings, connected by two
vertical columellae.

The genus Parastephanus is the simplest among the Eutympanida, and exhibits
only two vertical rods or columellse, which connect the two parallel horizontal rino-s.
One of these latter must be regarded as the mitral or superior ring, the other as the
basal or inferior ring; whilst the two parallel columellse, connecting both, are the
remaining vertical parts of the sagittal ring, the upper and lower parts of which are lost.
By loss of the latter Parastephanus has probably been derived from Protympanium.

1. Parastephanus circularis, n. sp.

Two horizontal rings smooth, circular, of equal size, connected by two curved smooth columella-,
which are somewhat shorter than the diameter of the rin^s

O

Dimensions. — Diameter of the rings 0'08, length of the columellae 0'06.
Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

2. Parastephanus quadrispinus, n. sp. (PI. 93, fig. 21).

Two horizontal rings smooth, elliptical or nearly circular, of equal size, connected by two
vertical, slightly curved columellse, which are about as long as the radius of the rings. Each ring
bears two simple lateral spines, which in the mitral ring are curved downwards, in the basal ring
upwards, possibly the last remains of a reduced frontal ring.

Dimensions. — Diameter of the rings 0'09, length of the columellae G"05.

Habitat. — North Pacific, Station 236, surface.

3. Parastephanus asymmetricus, n. sp. (PI. 82, fif. 10).

Two horizontal rings thorny, of equal size, irregularly ovate or nearly semicircular, and of some-
what asymmetrical form. The two connecting parallel columellfe are straight, cylindrical, about as
long as the diameter of the rings. The peculiar asymmetry in the form of the rings raises the
possibility that the two columellaa in this species are the remaining parts of a frontal ring, and
that the sagittal ring has altogether disappeared. In this case the convex half of both rings would
be the ventral, the straight half the dorsal part.

Dimensions. — Diameter of the rings 01, length of the columellas 0'08.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

REPORT ON THE RADIOLARTA. 1009

4. Parastephanus dispar, n. sp.

Two horizontal rings elliptical, thorny, of different sizes, the basal ring one and a half times as
broad as the mitral ring. The two connecting columellse are curved, somewhat longer than the
diameter of the mitral ring.

Dimensions. — Diameter of the basal ring O09, mitral 0'06 ; length of the columelke 0'07.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

Genus 436. Prismatium,1 Haeekel, 1862, Monogr. d. Radiol., p. 270.

Definition. — T ympanida with two simple horizontal rings, connected by three
vertical columellse.

The genus Prismatium was hitherto the only known form of the Tympanida, and the
only species described in 1862 in my Monograph was Prismatium tripleurum (foe. cit.,
p. 270, pi. iv. fig. 6). A new species from the Challenger collection (PL 93, fig. 22),
Prismatium tripodium, explains the true structure of this remarkable genus. The skeleton
is composed of nine siliceous rods, corresponding to the edges of a trilateral prism.
Six of these are horizontal, and enclose the two parallel triangular horizontal gates,
the superior of which is formed by the mitral or coryphal, and the inferior by the basal
or cortinar ring. The three other rods are vertical and nearly parallel, and connect (as
lateral edges of the prism) the corresponding corners of the two parallel horizontal
triangles. Two of these vertical columellse, together with the two horizontal parallel rods
connecting them, represent . the complete frontal ring, whilst the third vertical columella
is the posterior half of the sagittal ring, the other parts of which are lost.

1. Prismatium tripodium, n. sp. (PI. 93, fig. 22).

Mitral ring triangular, somewhat smaller than the triangular basal ring, both connected at the
corners by three vertical, slightly curved columelLs. From the six corners arise six radial spines
of different size and form ; the two paired spines of the mitral ring are simple and very small,
whilst those of the basal ring are three times as long and bear a lateral branch. The odd spine of
the third corner is on both rings larger, and distinguished by some thorns. This difference seems
to indicate that these two odd spines correspond to the apical horn and the caudal foot of Cortina,
and the eolumella between them is the rest of the reduced sagittal ring. In this case the quad-
rangular vertical ring, which is composed of the two paired columellse and the two connecting
horizontal rods, would be probably the frontal ring.

Dimensions. — Length of the shell 0'09, breadth 0'07,

Habitat. — Equatorial Atlantic, Station 347, surface.

1 Prismatium=A small prism ; •x-eiaftanei.
(ZOOL. CHALL. EXP. PAST XL. 1886.) Er 127

1010 THE VOYAGE OF H.M.S. CHALLENGER.

2. Prismatium tripleurum, Haeckel.

Prismatium tripleurum, Haeckel, 1862, Monogr. d. Radiol., p. 270, Taf. iv. fig. 6.
Acanthodesmia prismatium, Haeckel, I860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 799.

Mitral and basal rings of equal size, equilateral triangular, both connected at the corners by
three vertical equal cohimellas. From the six corners arise six short, equal, conical radial spines.
The nine rods of the shell correspond to the nine edges of a triangular equilateral prism.

Dimensions. — Length of the shell O044, breadth 0'032.

Habitat. — Mediterranean (Messina), surface.

Genus 437. Pseudocubus,1 n. gen.

Definition. — T ympanida with two simple horizontal rings of different sizes,
connected by four divergent columellse.

The genus Pseudociibus exhibits the characteristic form of an obelisk, or a truncated
four-sided pyramid. The four edges of this obelisk, or the four " columellse," are the
remaining parts of the two incomplete vertical rings ; two opposite edges are the dorsal
and ventral rod of the sagittal ring ; the two alternate edges between these are the
lateral rods of the frontal ring. The two horizontal rings, which become connected by
the four divergent columellae, are the smaller mitral ring and the larger basal ring ;
both are either square or nearly circular.

1. Pseudociibus obelisciis, n. sp. (PI. 94, fig. 11). .

Mitral ring square', with circular gate and two divergent simple spines on each corner. Basal
ring twice as broad, square, with four convex sides and one simple spine on each corner. Four
columellffi straight. All twelve rods with three smooth edges.

Dimensions. — Breadth of the mitral ring 0'02, of the basal ring 0'05.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Pseudocubus octostylus, n. sp.

Mitral ring square, with one stout pyramidal spine on each corner. Basal ring twice as broad,
square, also with a single strong spine on each corner. Four columellce straight. All twelve rods
with three smooth edges.

Dimensions. — Breadth of the mitral ring 0'04, of the basal ring O'OS.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

1 Pseudocubus = False cube ; i^ivoos, xvfrs.

REPORT ON THE RADIOLARIA. 1011

3. Pseudocubus hexapylus, n. sp. (PL 94, fig. 12).

Mitral ring circular, two-thirds as broad as the subcircular, or -nearly square, basal ring ; both
rings with a simple spine on the two sagittal corners (dorsal and ventral), with a forked or branched
larger spine on the two lateral corners (right and left). All twelve rods more or less curved and thorny,

Dimensions. — Breadth of the mitral ring 0'07, of the basal ring 01.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

•

•

Genus 438. Lithocubus,1 Haeckel, 1881, Prodromus, p. 447.

Definition. — T ympanida with two simple horizontal rings of equal size,
connected by four parallel vertical columellse.

The genus Lithocubus is very remarkable for the regular cubical form of the
skeleton, which is composed of .twelve siliceous rods, corresponding to the twelve edges
of a cube. Eight of these are horizontal, and enclose the two parallel square horizontal
gates, the superior mitral and the inferior basal gate. The four other rods are vertical,
parallel, and connect (as lateral edges of the cube) the corresponding corners of the two
horizontal squares. Two opposite ones of these four vertical columellae are the remaining
halves of the incomplete sagittal ring; the two alternate are the remaining halves of the
incomplete frontal ring. The four lateral gates between these four columellse are also
square or rectangular, and either of the same size as the two horizontal gates, or some-
what larger. Lithocubus may be derived from Acrocubus by reduction of the coryphal
and the basal part of the primary sagittal ring, the only remaining parts of which are
the anterior and the posterior columellse.

1. Lithocubus geometricus, n. sp. (PL 94, fig. 13).

The twelve rods, corresponding to the edges of the geometrical cube, are straight and smooth ;
the eight corners provided with a small conical thorn. The shell exhibits six equal square sides,
and represents therefore exactly the geometrical form of a cube.

Dimensions. — Diameter of the cube 0'05 ; thickness of the bars O'OOS.

Habitat. — Tropical Pacific, Station 224, depth 1850 fathoms.

2. Lithocubus octacanthus, n. sp.

The twelve rods of the cubical shell are slightly curved, convex, smooth, as in the similar
preceding species. It differs from that in the development of eight slender radial spines, arising
from the eight corners of the geometrical cube, from two to three times as long as its diameter,
and lying opposite in pairs in its diagonals.

Dimensions. — Diameter of the cube 0'06 ; length of the spines 0'15.

Habitat. — North Atlantic, Canary Islands, surface.

1 Lithocubws=Cn\)e ofsilex; x/^oj, *vfio;.

1012 THE VOYAGE OF H.M.S. CHALLENGER.

3. Lithocubus vinculatus, Haeckel.

Acanfhodesmia vinaulata, J. Miiller, 1856 (jiartim), Abhandl. d. k. Akad. d. Wiss. Berlin,
Taf. i. fig. 7 (not 4-6).

The twelve rods of the cubical shell are curved and armed with scattered, simple, short spines.
The figure 7 of Johannes Miiller (loc. cit.) corresponds exactly to the Mediterranean form observed
by me at Portofino, and is quite different from his true Acanthodesmia vinculata (loc. cit., figs. 4—6),
so that I have no doubt he did observe these two different species (compare above, p. 975).

Dimensions. — Diameter of the cube 0'07 ; length of the spines 0'02.

Habitat. — Mediterranean (Nice, Portofiuo).

4. Lithocubus astragalus, n. sp. (PI. 82, fig. 12).

The twelve rods of the cubical shell are stout and slightly curved, armed with numerous,
simple, and irregularly branched spines. Eight larger spines, branched like a deer's antler, arise
from the eight corners of the cube.

Dimensions. — Diameter of the cube -O'l to 0'12 ; length of the corner spines 0'05 to 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 439. Circotympanum,1 n. gen.

Definition. — Tympanida with two simple different horizontal rings, connected by
numerous (six to eight or more) divergent columellse.

The genus Circotympanum comprises those Tympanida in which two simple hori-
zontal rings of different size (an upper smaller " mitral ring," and a lower larger " basal
ring ") are connected by a variable number of divergent rods or columellaa (at least six or
eight). Circotympanum is probably derived from Tympaniscus or Tympanidium by
partial reduction of the sagittal ring, the upper (apical) and lower (basal) part of which
is lost. The geometrical fundamental form is a truncated pyramid with six to eight or
more edges.

1. Circotympanum hexagonium, n. sp.

Mitral and basal ring hexagonal, the latter twice as broad as the former, each with a simple
small spine on the six corners. Six columellse nearly straight, as long as the radius of the basal
ring. All rods with three prominent edges.

Dimensions. — Breadth of the mitral ring 0'06, of the basal ring O'll.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.
1 Circotympanum = Drum with rings ; x/jxoj,

REPORT ON THE RADIOLARIA. 1013

2. Circotympanum octogonium, n. sp. (PL 94, fig. 17).

Mitral and basal rings octagonal, the latter one and a half times as broad as the former. Eight
columellje slightly curved, thorny. The mitral ring bears on each corner a short ascending spine,
the basal ring a larger, thorny, obliquely descending spine, which has some recurved thorns on
the upper edge. All rods more or less thorny.

Dimensions. — Breadth of the mitral ring 0'06, of the basal ring 0'09.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Circotympanum decagonium, n. sp.

Mitral and basal rings circular, the ktter nearly twice as broad as the former, both armed with
scattered irregular thorns. Ten columellaj smooth, curved.

Dimensions. — Breadth of the mitral ring 0'07, of the basal ring 012.
Habitat. — North Pacific, Station 244, depth 2900 fathoms.

Genus 440. Eutympanium,1 Haeckel, 1881, Prodromus, p. 447.

Definition. — Tympanida with two simple equal horizontal rings, connected by
numerous (six to eight or more) parallel and vertical columellse.

The genus Eutympanium contains those Tympanida in which the drum-shaped shell is
composed of two simple, parallel and equal horizontal rings, and numerous vertical and
parallel rods or columellse connecting them. The number of the latter is at least six or
eight. Two opposite of these must be regarded as remaining vertical parts of the sagittal
ring, two others as parts of the frontal ring, whilst the other columellse (between the
former and the latter) are secondary and intercalated. Therefore Eutympanium may be
derived from Tympanidium by reduction and loss of the apical and basal parts of the
sagittal ring.

1. Eutympanium musicantum, n. sp. (PI. 83, fig. 2).

Eight parallel and vertical columellce, simple, straight and smooth. Both .horizontal rings equal,
circular, each armed with eight to twelve short conical thorns.
Dimensions. — Height of the shell 0'09, breadth 0'07.
Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

1 Eutympanium = Nice small drum; tv,

1014 THE VOYAGE OF H.M.S. CHALLENGER.

2. Eutympanium octonarium, n. sp.

Eight vertical columellae slightly curved, thorny. Both horizontal rings equal, octagonal, each
armed with eight large, irregularly-branched spines, which on the mitral ring are directed obliquely
upwards, on the basal ring downwards.

Dimensions. — Height of the shell 012, breadth 01.

HaUtat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Eutympanium coronarium, n. sp.

Eight thorny columellae, obliquely descending and curved like a bow, divergent in the upper
part, convergent in the lower. Basal ring circular, mitral ring octagonal. Both horizontal
rings armed with eight stout thorny spines, which on the mitral ring are smaller and directed
obliquely upwards, on the basal ring larger and directed downwards, each with a recurved hook.

Dimensions. — Height of the shell 0'08, breadth 0-06.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Eutympanium militare, n. sp. (PL 82, fig. 11).

Ten parallel and vertical columellae straight and smooth, cylindrical. Both horizontal rings
equal, circular, armed with numerous short conical spines, divergent in all directions. Ten to
twenty spines on each ring larger than the others.

Dimensions. — Height of the shell 01, breadth 0'08.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

5. Eutympanium dodecarium, n. sp.

Twelve vertical columellae, slightly curved, smooth. Mitral and basal rings circular, both
horizontal rings armed with twelve stout, irregularly-branched spines, which are prolongations of
the columellae, and on the mitral ring directed upwards, on the basal ring downwards.

Dimensions. — Height of the shell 013, breadth 01.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

REPORT ON THE RADIOLARIA. 1015

Order VI. CYRTELLAEIA, Haeckel, 1881.

Definition. — NASSELLAKIA with a complete lattice-shell enveloping the central
capsule.

Suborder I. SPYEOIDEA, Haeckel.

Spyridina,, Ehrenberg (pro parte), 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Zygocyrtida, Haeckel, 1862, Monogr. d. Eadiol., p. 291.
Zygocyrtida, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 501.
Acanthodesmida, R. Hertwig, 1879, Organismus der Radiol., p. 68.
Spyrida vel Spyroidea, Haeckel, 1881, Prodromus, p. 440.

Definition. — NASSELLARIA with a complete lattice-shell, exhibiting constantly a
bilocular cephalis with a sagittal constriction.

The suborder Spyroidea, and the two following closely allied suborders,
Botryodea and C y r t o i d e a, represent together that large group of Radiolaria
which I first described in my Monograph (1862, pp. 272, 280) as the family Cyrtida, but
afterwards as a separate order (or sublegion) under the name Cyrtellaria (1883,
Jena. Sitzungsber., Feb. 16, p. 18). This group comprises all those MONOPYLEA or
NASSELLAKIA which possess a complete lattice-shell, whilst the preceding P 1 e c t e 1-
1 a r i a never develop a perfect fenestrated shell enveloping the central capsule. The
Spyroidea differ from the other Cyrtellaria (Botryodea and Cyrtoidea)
in the bilocular shape of the cephalis, which is bisected by the sagittal ring and a
corresponding longitudinal constriction into two symmetrical halves.

The Spyroidea appear in the first system of Polycystiua of Ehrenberg (1847,
loc. cit., pp. 53, 54) as the fourth of his seven families, under the name Spyridina, with
the following definition : — " Testae nucleo destitutes (associates et coalitaa) ; cellulse binse
clathratse, nucis forma ainplse, strictura longitudinal! levius discretae." Ehrenberg united
them with his " Polycystina composita or SPUMELLAEIA " and separated them from the
closely allied " Polycystina solitaria or NASSELLARIA." He distinguished among them
five genera, two of which have no external appendages (Dictyospyris and Pleurospyris),
whilst the other three possess spiny or lamellar appendages (Ceratospyris, Cladospyris,
and Petalospyris). These five genera and the accompanying definitions were also
repeated in the same terms in the last system of Ehrenberg (1875, loc. cit., p. 157).
In my Monograph (1862, pp. 280, 291) the Spyroidea are enumerated as a sub-

1016 THE VOYAGE OF H.M.S. CHALLENGER.

family of the Cyrtida, under the name Zygocyrtida, with the following definition : —
" Lattice-shell divided by an annular sagittal longitudinal constriction into two neigh-
bouring equal joints or chambers." I adopted at that time the above five genera of
Ehrenberg, only eight species of which were known.

Richard Hertwig gave in 1879 the first accurate description of the central capsule of
the Spyroidea, and demonstrated that they possess the same characteristic structure
of the capsule, with a porochora and a podoconus, that is common to all MONOPYLEA.
He separated the Zygocyrtida from the other Cyrtida, and united them with the
Stephoidea (Lithocircus) in the family Acanthodesmida. In my Prodromus
(1881, p. 440) I adopted that division and put the " Spyrida or Spyroidea" as a
separate family between the Cyrtoidea and Stephoidea. I there gave the
following definition : — Monopylaria gemina, testa silicea clathrata gemina, cameris binis
juxta compositis, annulo vertical! sagittali contiguis, capsula centrali a testa inclusa,
Promorpha dipleura vel bilaterali, dextro et sinistro antimero symmetricis, piano sagittali
annuloque separatis. Polum superiorem axis verticalis vel principalis plerumque spina
apicalis (vel occipitalis) occupat, polum inferiorem ostium clathratum (poris tribus aut
quatuor aut pluribus) et spina caudalis (posterior). Ad dextram et sinistram duae spinae
laterales distant. Ab hac forma tripoda (Monocyrtida triradiata acuta cum annulo mediano)
diversse Spyridum formse derivandse sunt." I there divided the Spyrida into seven
subfamilies and forty-eight genera. Biitschli in 1882 published accurate researches on the
Zygocyrtida in his Beitrage zur Kenntniss der Radiolarien-Skelete, insbesondere der
der Cyrtida (Zeitschr. f. wiss. Zool., vol. xxxvi. p. 501, Taf. xxxii.). He gave a very
exact anatomical description of the skeleton of several fossil Spyroidea of Barbados,
and pointed out their close affinity to the Acanthodesmida on the one hand, and to the
Cyrtida on the other. Regarding their phylogenetical relation, he supposed that the
Zygocyrtida have descended from the Acanthodesmida (our Stephoidea) and are the
ancestors of all other Cyrtida. The best part of this valuable paper of Biitschli is his
exact description of the sagittal ring and its apophyses, producing the basal plate ; and
the general conception thus derived of the essential parts of the skeleton in all
MONOPYLEA, bearing a sagittal ring. But his general conclusions were partly erroneous,
since the fossil Spyroidea and Cyrtoidea of Barbados, upon which they were
founded, contain only the minority of genera of the large group; and many important
and typical forms remained unknown to him.

The numerous new genera discovered in the rich collection of the Challenger, and
mainly in the wonderful Radiolarian ooze of the Central Pacific (Stations 263 to 274)
throw a new light upon the complicated affinities of the whole group, and manifest a far
greater richness in developmental variations and admirable morphological productions than
Biitschli could suppose. The following description, however, must remain very incom-
plete, since the exact and thorough study of all individual forms, in the same manner as

EEPORT ON THE RADIOLAEIA. 1017

Biitschli had done in the case of a small number of species, would require several years.
I can therefore only give the basis of further researches.

In the majority of Spyroidea the three essential elements of the Nassellarian
skeleton are easily recognisable, viz. : — A, the vertical sagittal ring of the Stephoidea;
B, the basal tripod of the Plectoidea; and C, the latticed cephalis of the C y r t e 1-
1 a r i a. These three elements are constantly so combined that the primary sagittal
ring bisects the cavity of the lattice-shell and produces an external, longitudinal, more or
less distinct constriction, separating the lateral inflated halves of the bilocular cephalis;
while the three divergent feet of the basal tripod descend from the cortinar or basal
plate of the cephalis. The number of the feet is often augmented ; they are rarely want-
ing (probably reduced). The sagittal ring is constantly present, though its relation to the
shell-wall exhibits many modifications. The bilocular form of the fenestrated cephalis,
with its sagittal constriction, is characteristic of all true Spyroidea, and separates
them from the Botryodea (with multilobate cephalis) on the one hand, and from"
the Cyrtoidea (with simple cephalis) on the other. There are, however, some
intermediate forms between these three suborders of Cyrtellaria, which show a
direct transition to one another. Almost constantly the length of the three dimensive
axes in the cephalis of the Spyroidea is so different that the lateral or frontal axis is
the longest, the sagittal or dorso-ventral axis the shortest, and the principal or longitudinal
axis intermediate between them. As in all dipleuric or bilaterally symmetrical forms, the
two poles of the frontal axis are equal, whilst the two poles of the sagittal and of the
principal axis are more or less different. In only a few forms of Spyroidea these
differences are difficult to make out ; usually the dorsal side is distinctly different from
the ventral, and the apical side from the basal. A perfect knowledge of the dipleuric
shell requires therefore accurate observation from all six sides.

The suborder of Spyroidea is here divided into four different families. In the
first and original family, the Zygospyrida, the shell is represented by the bilocular
cephalis only. The second family, Tholospyrida, is distinguished by a fenestrated cupola
or galea, a hemispherical or conical dome, arising from the upper or coryphal face of the
cephalis. In the third family, Phormospyrida, a thorax is developed, or a fenestrated
basal chamber, arising from the lower or basal face of the cephalis. The fourth family,
Androspyrida, combines the characters of the second and the third family, a galea arising
from the upper and a thorax from the lower face of the cephalis.

The bilocular cephalis, as the most important and constant part of the skeleton in all
Spyroidea, requires a further general consideration. Its lattice-work, very variable in
the numerous species, is usually more or less different on the six sides of the nut-shaped
shell. Its most important part is the horizontal baeal plate or lower face, and the
sagittal ring arising from it in the vertical median plane. This part of the shell
corresponds exactly to the skeleton of the Semantida, and exhibits the same modifications

(ZOOL. CHALL. EXP. PART XL. — 1886.) Er 128

1018 THE VOYAGE OF H.M.S. CHALLENGER.

as in that family ; it is therefore probable that the majority of the Spyroidea(if not
the whole group) have been derived directly from the Semantida by further development
of network from the fenestrated ring of Clathrocircus. Whilst in this latter Semantid
the two lateral sides of the central capsule remain naked, in the Spyroidea they
become enclosed and covered by lattice-work, which arises on the right and left from
the ring. In some forms, however, as in the Ceratospyris acuminata of Hertwig, and in
my Perispyrida, the frontal ring also of the Coronida and the mitral ring of the Tympanida
appear as the initial parts of a complete latticed cephalis.

The basal plate of the cephalis, or the "cortinar plate," the " Basal-Scheibe " of
Butschli, has constantly, according to this author, two pairs of pores, an anterior smaller
pair of jugular pores (the pores I of Butschli) and a posterior larger pair of cardinal
pores (the pores II in his description) (compare PI. 95, figs. 3, 6). This applies to
the majority of Spyroidea, but by no means to the whole group. We find basal
plates with two pores only (PI. 95, fig. 1), with three pores (figs. 2, 5), with six pores
(figs. 4, 7), with nine pores (PL 87, fig- 2), &c. The forms with two basal pores may be
derived directly from Semantis (PI. 92, figs. 1, 2); the common forms with four pores
from Semantrum (figs. 3-5) ; the rarer forms with six pores from Semantidium (figs. 6, 7);
and the forms with three pores from Cortiniscus, &c. In this as well as in other
respects the variety of different forms and of developmental variations is far greater than
Butschli (1882, loc. cit.) supposed. The bars between the pores of the basal plate
possess the same value and the same names as in the Semantida (compare above, p. 954).

The coryphal plate of the cephalis, its upper or apical lattice-plate, does not exhibit such
important differences as the opposite basal plate, is far less variable, and is usually pierced
by numerous, smaller pores. Some larger pores lie, often in pairs, on the right and left
side of the sagittal constriction, and have in some groups a regular form and disposition.
Either in the middle of the coryphal plate, or (usually) nearer to its dorsal margin,
there arises in the majority of Spyroidea an apical horn, directed either vertically or
more or less obliquely backwards. In many Spyroidea three horns are developed in
the coryphal plate, the odd middle apical horn and two paired frontal or lateral horns
arising on each side of the latter and directed more forwards (PL 84, figs. 9—12).
Sometimes the apical horn disappears, while the two frontal horns remain (PL 95, fig. 1 2).

The anterior or ventral plate of the cephalis (the " Hinterseite " of Butschli), and
the posterior or dorsal side (the " Vorderseite " of that author), exhibit in the majority
of Spyroidea more or less marked differences in the number, form, and disposition
of their pores, which require a far more accurate description than is here possible.
Usually the sagittal constriction of these two plates, produced by the primary vertical
ring, is deeper and sharper in the middle of the ventral than in that of the dorsal plate.
On both sides of the ring there appear in each plate usually two or three pairs of larger
pores, whilst numerous smaller pores are situated towards the lateral sides. We may

REPORT ON THE RADIOLARIA. 1019

distinguish the large pores of the ventral plate as facial pores (upper orbital, middle
nasal, and lower maxillary pores), and the opposite large pores of the dorsal plate as
occipital pores (upper epoccipital, middle mesoccipital, and lower suboccipital pores). A
closer comparison of these pores, and of the separating bars in the numerous Spyroidea,
may show a regularity of development similar to that offered by the homologies of the
parts in the skeleton of the Echinodermata, or of the bones in the skull of the
Vertebrata.

The two convex lateral plates of the cephalis, or the right and left sides, both
symmetrically equal, do not exhibit the same regularity in the shape, number, and
disposition of the pores that the four other sides do. Usually their pores are much
smaller and more numerous. In very few forms only a distinct frontal ring is visible
(corresponding to that of the Coronida), and in this case the lateral pores are sometimes
disposed symmetrically on both sides of this ring. These Spyroidea may have
arisen directly from corresponding forms of Coronida.

The sagittal ring (or the primary vertical ring, inherited from the Stephanida and
Semantida, shows in the Spyroidea great variety in its form and in its relation
to the cephalis. These variations are far greater than Biitschli (1882, loc. cit.)
supposed. We may distinguish the following six principal cases : — A. The ring lies
completely in the wall of the cephalis, and causes a deep sagittal constriction in it. In
this case the lower part or basal segment of the ring separates the basal pores into pairs ;
its anterior part or ventral rod the facial pores ; its upper part or coryphal rod the apical
pores ; and its posterior part or dorsal rod the occipital pores. No part of the ring is
free in the shell-cavity. B. The greater part of the ring lies enclosed in the shell-
wall ; only its dorsal rod arises free in the shell-cavity and ascends vertically or
obliquely to the apex, where it is usually prolonged into the apical horn. This seems
to be the most common case. C. The coryphal and the basal part of the ring lie
enclosed in the shell-wall, with its dorsal and ventral rod free in the shell-cavity ; the
dorsal rod ascends vertically to the apex, the ventral rod obliquely upwards to the
upper part of the facial plate (the nasal or orbital region). This case, regarded by
Biitschli as the usual one, is far less common than he supposed. D. The greater part
of the ring lies free in the shell-cavity, its basal rod only is enclosed in the shell-wall,
and separates the right from the left group of the cortinar pores. This case seems to
be rarer than the preceding. E. The whole ring lies free in the shell-cavity, and is
connected with the sagittal constriction of the shell-wall by numerous short radial beams.
The distance of the shell-wall from the enclosed ring is usually least on the basal
rod, and greatest on the dorsal rod. F. The whole ring lies free in the shell-cavity (as
in the preceding case), and is connected by numerous short radial beams with a secondary
larger, concentric sagittal ring, which is developed in the longitudinal constriction of
the shell-wall.

1020 THE VOYAGE OF H.M.S. CHALLENGED.

Comparing these six principal cases, in respect of the relation of the primary sagittal
ring to the cephalis of the Spyroidea, we may suppose that they represent together
a continuous phylogenetical series, of which the first (A) is the original, and the last
(F) the latest case ; and that the true cause of the various changes is a successive
separation of the ring, which becomes more and more free and independent from the
lattice-plate of the cephalis. Since the intimate study of the structure of the cephalis in
many Spyroidea is very difficult, it requires further accurate observations (from all
six sides of the shell). There are also some other more difficult complications of its
structure, which cannot be solved without exact study and extended comparison.

Of peculiar importance for the differentiation of the numerous genera of the
Spyroidea are the basal feet or the descending and diverging apophyses, which are
developed from the base of their cephalis. In general they exhibit the same typical shape
which we find in the Plectellaria as well as in the Cyrtoidea, and which we
regard therefore as an important common character of the majority of NASSELLARIA. We
may therefore distinguish here also the three primary, and the other ones as secondary
feet. The three primary feet, or the " cortinar feet," are the same that we found in the
Plagonida and Plectanida, in Cortina and Cortiniscus among the Stephoidea, and in
the majority of Cyrtoidea. They also reappear in the same characteristic disposition
and connection with the basal plate of the cephalis, in the majority of S p y r o i d e a. The
odd caudal foot (c) is the lower prolongation of the dorsal rod of the sagittal ring, which
is prolonged upwards into the apical horn. The two paired pectoral feet, however
(p'> P")> are the descending prolongations of the coracal rods (e) which separate the jugular
pores (i) from the cardinal pores (k) of the cortinar plate (compare PI. 95, figs. 2-6).

The three cortinar feet are nearly equally developed in the majority of Spyroidea
(compare Pis. 84, 89). But often the odd caudal foot exhibits a different shape from
that of the two paired pectoral feet, and in many genera of the group it becomes more or
less rudimentary. It has quite disappeared in the subfamily Dipospyrida (PL 85) ; here
the two pectoral feet only are developed (often excessively), and are usually opposite in
the frontal plane. Such dipodal forms, very common in the Spyroidea, are never
found in the Cyrtoidea.

The secondary feet, which we contrast with the three primary feet as later productions,
exhibit great variations in number and development. Very frequently three interradial
secondary feet become developed, alternating with the three primary cortinar or perradial
feet, and opposed to them in pairs (PL 95, figs. 7, 8). In these hexapodal Spyroidea
(or Hexaspyrida) an odd anterior or sternal foot (z) is opposite to the odd caudal foot,
and two paired posterior or tergal feet (ttl tn) to the two pectoral feet. When the sternal
foot becomes rudimentary or lost, pentapodal forms arise (Pentaspyrida, PL 95, figs.
9-11), and when the two odd feet (caudal and sternal) disappear, tetrapodal forms
arise with two pairs of feet (Therospyrida, PL 89, figs. 5, 6). The latter differ from

REPORT ON THE RADIOLARIA. 1021

those quadrupedal forms in which two opposite sagittal feet (the caudal and sternal)
alternate in the form of a cross with two paired lateral or pectoral feet (Tetraspyrida,
PL 53, figs. 19, 20). In many Spyroidea the number of basal feet is greatly
increased, and they form a regular radial corona around the basal plate, like a circle
of tentacles (Polyspyrida, PL 87). In this latter case the feet are usually flat and
lamellar, whilst in the other groups they exhibit a very variable form, as is seen in
Pis. 83-89.

The Central Capsule of the Spyroidea has been accurately observed in only a few
genera, and requires a further exact examination regarding the different modifications
which occur in their different families. It is very probable that these will agree with the
well known modifications in the corresponding groups ofCyrtoidea. The characteristic
Monopylean structure of the capsule (with porochora and podoconus) was first described
by Eichard Hertwig in his Ceratospyris acuminata (loc. cit., p. 72, taf. vii. fig. 2). I
found the same afterwards in many other forms. In the Zygospyrida and Tholospyrida
the central capsule seems to be usually bilobate (bisected by the sagittal ring), and
enclosed in the two chambers of the cephalis. The two lobes of the capsule (right and
left) are equal and connected by a smaller middle part, which contains the transverse
elliptical nucleus and is enclosed by the sagittal ring ; often each lobe contains a large
oil-globule. In some forms, however, three or four lobes (sometimes perhaps more) are
developed, which pierce the cortinar pores of the basal plate and depend freely between
the basal feet (PL 53, fig. 19). In the Phormospyrida and Androspyrida the formation
of such basal lobes seems to be more frequent ; they are here enclosed by the thorax.
Usually each lobe contains a large oil-globule. In Nephrospyris (PL 90) and in some
similar genera the central capsule is violin-shaped, deeply bisected by the sagittal ring ;
in each of the two lobes a series of oil- vesicles is developed at both poles of the transverse
axis (figs. 7, 10) ; the nucleus, a transverse cylindrical body, is placed in the latter. In
the periphery of the voluminous calymma of this singular genus a large number of
globular cells are developed (figs. 7, 10), probably symbiotic xanthellae. In some forms
of Nephrospyris these xanthellse are enclosed by a peculiar inflated girdle, developed in
the periphery of the kidney-shaped skeleton (PL 90, figs. 1, 4-6).

Synopsis of the Families of Spyroidea.

Shell without thorax; no second shell- t Cephalis without galea (or apical cupola), 1. ZYGOSPYRIDA.
joint, developed from the base of the <
cephalis. ( Cephalis with a galea (or apical cupola), . 2. THOLOSPYRIDA.

Shell with a thorax, or a second shell- ( Cephalis without galea (or apical cupola), 3. PHORMOSPYRIDA.
joint, developed from the base of the <j
cephalis. ( Cephalis with a galea (or apical cupola), . 4. ANDROSPYRUA.

1022 THE VOYAGE OF H.M.S. CHALLENGER.

Family LII. ZYGOSPYRIDA, n. fam. (Pis. 84-87).

Definition. — S pyroidea without galea and thorax ; the shell consisting of the
bilocular cephalis only and its apophyses.

The family Zygospyrida is by far the richest among the four families of Spyroidea,
the number of genera in the whole suborder amounting to forty-five, in the former to
twenty-eight ; and the number of species in the latter to two hundred and thirty-seven,
in the former to one hundred and seventy-two. The number of individuals also found
in many species of Zygospyrida is far greater than in any species of the three other
families. The shell of the Zygospyrida is represented by the bilocular cephalis only, and
never develops a galea (as in the Tholospyrida) nor a thorax (as in the Phormospyrida
and Androspyrida). The three latter families have therefore been derived from the
former as their common ancestral group.

The Zygospyrida are very similar and nearly related to the Monocyrtida, and in both
groups the cephalis alone represents the whole shell. Therefore in 1882, Biitschli, in
the paper mentioned above (p. 1016), maintained the opinion, that these two groups were
identical. But there is this important difference between them, that in the Zygospyrida
(as in all S p y r o i d e a) the cephalis is bilocular, with a sagittal constriction, separating
the right and left chambers. In the Monocyrtida, however (as in all C y r t o i d e a), the
cephalis is unilocular, forming a quite simple chamber without sagittal constriction. Cor-
respondingly the primary sagittal ring in all Zygospyrida is well preserved and usually
complete, while in the Monocyrtida it is never complete, and often quite absent.
Another difference is indicated by the form of the central capsule, which in the
Zygospyrida is usually bilobed, and more developed in the frontal axis, whilst in the
Monocyrtida it is commonly ovate, and more developed in the principal axis.

The important questions of the origin and phylogenetical relation of these two
similar groups of NASSELLARIA form a very complicated and difficult problem, and we
do not at present possess the means of solving it. It may be that a part of the
Monocyrtida has been derived from the Zygospyrida (as Biitschli erroneously supposes
for all), but the contrary is also possible. A third possibility is the independent origin
of both groups from the Semantida. But we shall see afterwards, in the description of
the Monocyrtida, that a great part of this group may with greater probability be derived
from the Plectoidea than from the Stephoidea, and that another part of them
has probably been derived quite independently from the Nassellida. Regarding the
complicated relations of these similar groups, mentioned above (pp. 892-894), it seems
hopeless here to discuss further their difficult affinities ; but in any case it seems useful
or even necessary to separate the Monocyrtida from the Zygospyrida,

REPORT ON THE RADIOLARIA. 1023

The cephalis of the Zygospyrida possesss all the characteristic features which we have
described above as belonging to the Spyroideain general (p. 1017), and a survey of the
Pis. 84-87 exhibits the most important modifications of its shape (compare also PI. 95,
figs. 1-13). Therefore we may avoid useless repetitions by referring to the description
given above. We will only point out that the bilocular character of the cephalis (in oppo-
sition to the simple cephalis of the Monocyrtida) in the majority of Zygospyrida is apparent
on the first view, and that it is always demonstrated by an accurate examination of the
sagittal ring and its relation to the longitudinal constriction of the cephalis (compare
p. 1019). The basal plate or cortinar plate exhibits usually four typical pores (two smaller
jugular, i, and two larger cardinal, &), but this is by no means a general rule, as
Biitschli thought ; moreover, instead of four cortinar pores, there are frequently found
three or six or some other numbers (compare above, p. 1018).

The top of the cephalis in the majority of Zygospyrida bears an apical horn, as an
upper prolongation of the dorsal rod of the sagittal ring ; it is often of unusual size and
shape (PL 85, figs. 5-11 ; PL 95, fig. 8, &c.). In several genera two lateral or frontal
horns are developed on both sides of the former (PL 84, figs. 9-12 ; PL 86, figs. 5-13).
Sometimes these two alone are present, while the original apical horn is lost by reduction
(PL 95, fig. 12). In other genera the apical face bears no horns ; probably they are lost
by reduction.

The greatest variety of forms is produced in the Zygospyrida by the different
number, disposition, and shape of the feet, or the basal apophyses arising from the base
of the cephalis. Regarding these remarkable differences, we may distinguish eight
subfamilies. The common ancestral group of all are probably the Tripospyrida, which
possess the three typical basal feet of Cortina and Cortiniscus, an odd caudal and two
paired pectoral feet (PL 84). From these may be derived the Dipospyrida (PL 85) by
loss of the caudal foot, the Tetraspyrida by development of an odd sternal foot (PL 53,
figs. 7, 8, 19), and the Hexaspyrida by development of three secondary interradial between
the three primary perradial feet. The Pentaspyrida may have been derived from the
latter by loss of the sternal foot (PL 95, figs. 9-11), and the Therospyrida by loss of the
two sagittal feet (PL 89, figs. 5, 6). The Polyspyrida bear numerous (seven to twelve
or more, often twenty to thirty) basal feet, forming a corona around the cortinar plate
(PL 87) ; they may have been derived from the Tripospyrida or Hexaspyrida by further
multiplication of the feet. Finally, the Circospyrida exhibit no feet at all (PL 89,
figs. 7-12) ; they may be derived either from one of the preceding groups by complete
reduction and loss of the basal apophyses, or directly from those Semantida which
have no feet (Semantis, Semantrum, Clathrocircus, &c.).

1024

THE VOYAGE OF H.M.S. CHALLENGER.

I. Subfamily

Tripospyrida.
Three basal feet. (One
odd caudal and two
paired pectoral.)

Synopsis of the Genera of Zygospyrida.
Apex of the shell with one horn,
Apex of the shell with three horns, .
Apex of the shell without horns,
Apex with two large coryphal holes, right and left, .

II. Subfamily

Dipospyrida.
Two basal lateral feet.
(Originally the two
pectoral feet.)

not branched,

1

One

horn, .

without lateral

No horn. .

spines.

J

Two feet free, not grown
together.

Feet branched
like a tree.

}

One

horn, .

Feet with a

)

series of lateral

\
>

One

horn, .

spines.

f

III. Subfamily

Tetraspyrida.
Two sagittal and two
lateral feet.

Two feet grown together and [ Feet BUnple'
uniting to form a ring. \ -& ,
Apex with a horn.

Feet simple, not branched.

gerieg Q£

( Apex with one horn,
( Apex without a horn,
Apex with one horn,
Apex with three horns,
[ Apex without a horn,

f Apex with one horn,
V. Subfamily | Q dal pectoral and I

Pentaspyrida. V , , ', { £ i Apex with three horns,

Five basal feet.

[ Apex without a horn,

IV. Subfamily

Hexaspyrida.
Six basal feet.

Apex with one horn, .....
Apex with three horns (one apical and two frontal), .

VI. Subfamily

Therospyrida.
Four paired lateral <

feet. (Two pectoral | Apex with two lateral or frontal horns,
and two tergal.)

Apex without a horn,

VII. Subfamily

Polyspyrida.
Numerous (seven to

twelve or more)

basal feet.

' Apex with one horn, ....

Apex with three horns (one apical and two frontal), .
Apex with numerous horns, .
Apex without a horn, ....

VIII. Subfamily ( Apex with one horn, .

Circospyrida. '.
No basal feet. ( Apex without a horn,

441. Tripospyris.

442. Triceraspyris.

443. Tristylospyris.

444. CepTialospyris.

445. Dipospyris.

446. Brachiospyris.

447. Dendrospyris.

448. Dorcadospyris.

449. Gamospyris

450. Stephanospyris.

451. Tetraspyris.

452. Tessarospyri*.

453. Hexaspyris.

454. Liriospyris.

455. Cantharospyris.

456. Clathrospyris.

457. jEgospyris.

458. Pentaspyrig.

459. Zygospyris.

460. Elaphospyris.

461. Taurospyris.

462. Thei-ospyris.

463. Petalospyris.

464. Anthospyris.

465. Ceratospyris.

466. Gorgospyris.

467. Circospyris.

468. Dictyospyris.

REPORT ON THE RADIOLARIA. 1025

Subfamily 1. TRIPOSPYRIDA, Haeckel, 1881, Prodromus, p. 441.

Definition. — Z ygospyrida tripoda, with three descending basal feet (the same as
in Cortina, an odd posterior or caudal foot and two paired anterior or pectoral feet).

Genus 441. Tripospyris,1 Haeckel, 1881, Prodromus, p. 441.
Definition. — Z ygospyrida with three basal feet and one apical horn.

The genus Tripospyris (PL 84, figs. 1-7) is in the large group of Spyroidea
probably the most original and typical form, from which, as a common ancestral form,
all other genera of this polymorphous suborder may be derived. The shell is usually
shaped like a nut or thorax, and exhibits two paired lateral chambers, which are separated
by a distinct sagittal ring and a slighter or deeper sagittal constriction. The dorsal rod
of the ring is prolonged at the upper pole into an ascending apical horn, at the lower
pole into a descending caudal foot, whilst two paired pectoral or lateral feet arise from
the anterior pole of the basal rod. These three divergent basal feet and the apical horn
are the same four typical radial spines which we have encountered already in Plagoniscus
(Plagonida), in Plectaniscus (Plectanida), in Cortina (Stephanida), and in Cortiniscus
(Semantida). Compare above, p. 891. From all these Plectellaria, Tripospyris
differs in the development of a complete bilocular lattice-shell, having the characters of
the true Spyroidea. The numerous species of this genus may be placed in different
subgenera, according to the different number of collar pores or cortinar pores in the
basal plate (two, three, four, six, or more). These differences are very important,
however difficult to make out ; the following system therefore is a provisional one, and
requires further accurate observations.

Subgenus 1. Tripospyrantha, Haeckel.

Definition. — Basal plate with two large pores only (the primary jugular pores of
Semantis).

1. Tripospyris cortina, n. sp. (PI. 95, fig. 1).

Shell ovate, smooth, about as long as broad, with slight ovate sagittal stricture, and broad
primary ring in its wall. Basal plate with two large kidney-shaped collar pores only (cardinal
pores). Facial and occipital plates each with two pairs of large annular pores, and ten to twelve
pairs of small lateral pores. Apical horn and the three basal feet of equal length, one and a half
times as long as the shell, three-sided prismatic, straight, divergent.

Dimensions. — Shell 0'08 long, '0'09 broad ; horn and feet 0'15 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

1 Tripospyris = Basket with a tripod ; Tf/Vo?, airv^is-

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 129

1026 THE VOYAGE OF H.M.S. CHALLENGER.

2. Tripospyris cortiniscus, n. sp. (PI. 84, fig. 6).

Shell ovate, smooth, one and a third times as long as broad, with sharp ovate sagittal stricture
and broad primary ring. Basal plate with two large cardinal pores only. Occipital plate with two
pairs of very large pores ; facial plate and lateral sides with numerous smaller irregular roundish
pores. Apical horn small, conical, curved, half as long as the three basal feet, which are club-
shaped and three-edged, with thinner bases and half as long as the shell, strongly divergent.

Dimensions. — Shell 012 long, 0'09 broad ; horn 0'03 long, feet 0'06 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Tripospyris semantis, n. sp. (PI. 84, figs. 2, 3).

Shell subspherical, smooth, somewhat broader than long, with slight sagittal stricture and sub-
circular parietal primary ring. Basal plate with two large semicircular cardinal pores. Facial and
occipital plate each with two pairs of large annular pores and an odd large subapical pore ; lateral
sides with very numerous small roundish pores. Apical horn and caudal foot club-shaped, half as
long as the shell, angular, simple ; the two pectoral feet somewhat longer, nearly vertical, and at
the distal end with a small incision, nearly forked.

Dimensions. — Shell 01 long, 012 broad ; horn and feet 0'05 to 0'07 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Tripospyris diomma, n. sp. (PL 84, fig. 5).

Shell thorax-shaped, smooth, twice as broad as long, with deep sagittal stricture, two vaulted
ovate bosoms and smaller ovate internal primary ring. Basal plate with two large ovate cardinal
pores. Facial plate with three pairs, occipital plate with four pairs of large annular pores ; the
other lattice-work loose, with small and numerous irregular polygonal pores. Apical horn and
caudal feet slender and thin, curved, shorter than half the shell ; two pectoral feet also small, widely
divergent, more or less curved, deeply forked.

Dimensions. — Shell 01 long, 016 broad ; horn and feet 0'2 to 0'25 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Subgenus 2. Tripospyrella, Haeckel.

Definition. — Basal plate with three large collar pores (two paired posterior cardinal
pores, and an odd anterior sternal pore).

5. Tripospyris triomma, Haeckel.

Ceratospyris triomma, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xxi.
fig. 3.

Shell subspherical, tuberculate, with slight sagittal stricture and circular internal ring. Basal
plate with three large pores, which are sometimes (but not in every specimen) surrounded by a

REPORT ON THE RADIOLARTA. 1027

circle of very small pores. The other lattice-work with numerous small roundish pores. Apical
horn small, oblique, about as long as the shell. Three feet very large, cylindrical, curved, widely
divergent, four to five times as long as the shell. (In Ehrenberg's description the caudal foot is
erroneously described as " frontal spine " ; its figure exhibits the basal plate.)

Dimensions. — Shell 0-07 to 0'09 diameter ; horn 0'06 long, feet 0'3 to 0'4 long.

Habitat. — Fossil in Tertiary rocks of Barbados.

6. Tripospyris conifera, n. sp. (PI. 84, figs. 7, 7a).

Shell nearly hemispherical, papillate, with slight sagittal stricture and semicircular internal ring.
Basal plate with three large pores (sometimes, as in the figured specimen, with some small
accessory peripheral pores). The other lattice-work with subregular circular pores. Apical horn
shorter than the three basal feet, but of similar form, like an elegant ovate dimpled cone, spinulate,
with a smooth spindle-shaped pedicle, about as long as the shell.

Dimensions. — Shell O08 long, 01 broad ; horn 0'06 long, feet 0'08 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

7. Tripospyris triplecta, n. sp. (PI. 95, fig. 2).

Shell thorax-shaped, spiny, with deep sagittal stricture and semicircular internal ring. Basal
plate with three large collar pores. Facial plate with four pairs, occipital plate with three pairs
of large annular pores ; the other pores small, subregular, circular. Apical horn and the feet
slender, three -sided pyramidal, about as long as the shell.

Dimensions. — Shell 01 long, Oil broad ; horn and feet 01 to 015 broad.

Habitat. — Mediterranean, Corfu (Haeckel), surface.

Subgenus 3. Tripospyrissa, Haeckel.

Definition. — Basal plate with two pairs of collar pores (two larger posterior cardinal
pores and two smaller anterior jugular pores).

8. Tripospyris semantrum, n. sp. (PL 95, fig. 3).

Shell thorax-shaped, thorny, with deep sagittal stricture and subcircular ring. Basal plate
with four large collar pores (two smaller ovate jugular, and two larger pentagonal cardinal pores).
Facial and occipital plates also each with two pairs of large annular pores ; lateral sides with
smaller irregular polygonal pores. Apical horn and the three feet slender, prismatic, divergent,
longer than the shell.

Dimensions. — Shell 0'07 long, 0'08 broad; horn and feet Oil to 013 long.

Habitat. — South Atlantic, Cape of Good Hope (Wilhelrn Bleek), surface.

1028 THE VOYAGE OF H.M.S. CHALLENGER.

9. Tripospyris capitata, n. sp. (PL 84, fig. 1).

Shell subspherical, spiny, with slight sagittal stricture and ovate internal ring. Basal plate
with four large collar pores. Facial plate with three pairs and occipital plate with two pairs of
large roundish annular pores ; lateral lattice with smaller irregular pores. Apical horn and the
three feet subcylindrical, about half as long as the shell, straight, divergent, with a spherical, spinulate
knob at the distal end.

Dimensions. — Shell 0'09 long, 01 broad ; horn and feet 0'05 to 0'06 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

10. Tripospyris clavata, Haeckel.

Ceratospyris clavata, Butschli,1882, Zeitschr. f . wiss. Zool.,vol. xxxvi. p. 539,Taf. xxxii. fig. 13,a-c.

Shell subspherical, compressed, rough, with slight sagittal stricture and ovate internal primary
ring. Basal plate with four large collar pores (fig. 13,a, loc. cit.). The other lattice-work with
irregular small roundish pores. Apical horn and the three feet short and thick, scarcely half as
long as the shell, with a roundish spinulate knob at the distal end.

Dimensions. — Length of the shell 0'07 long, 0'08 broad ; horn and feet 0'02 to 0'03 long.

Habitat. — Fossil in Barbados.

11. Tripospyris tessaromma, n. sp.

Shell nearly cubical, spiny, with deep sagittal stricture and subcircular ring. Basal plate with
four large collar pores. Facial and occipital plates each also with two pairs of large square
annular pores ; lateral pores irregular polygonal. Apical horn half as long as the feet, which
are three times the length of the shell, cylindrical, slightly curved.

Dimensions. — Shell 01 long, 012 broad ; horn 015 long, feet 0'3 long.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

Subgenus 4. Tripospyromma, Haeckel.

Definition. — Basal plate with six or more collar pores. Commonly two small
anterior jugular pores, two large middle cardinal pores, and two small posterior cervical
pores ; sometimes several small accessory collar pores.

12. Tripospyris hexomma, n. sp. (PI. 95, fig. 4).

Shell thorax-shaped, tuberculate, with deep sagittal stricture and semicircular internal primary
ring. Basal plate with three pairs of pores. Facial plate with two pairs, occipital plate with
four pairs of large annular pores. Lateral pores smaller, irregular, polygonal. Apical horn and
caudal foot half as long as the shell and as the two pectoral feet ; all four spines cylindrical, two
to three times as long as the shell, slightly curved.

Dimensions. — Shell 01 long, 012 broad ; horn and feet 0'2 to 0'4 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

REPORT ON THE RADIOLARIA. 1029

13. Tripospyris semantidium, n. sp.

Shell nut-shaped, thorny, with sharp sagittal stricture and subcircular ring. Basal plate with
three pairs of large pores. Facial and occipital plates each with three pairs of large squarish
pores. Lateral pores small and numerous, irregular roundish. Apical horn half as long as the
shell and the three feet ; all four spines straight, cylindrical, with thickened club-shaped end.

Dimensions. — Shell 012 long, 013 broad ; horn 0'06 long, feet 015.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

14. Tripospyris eucolpos, n. sp. (PI. 84, fig. 4).

Shell thorax-shaped, smooth, with two vaulted bosoms, separated by a deep sagittal stricture
and an internal primary ring. Basal plate constricted, with three pairs of collar pores. The
other lattice-work with subregular circular pores. Apical horn and the three feet shorter than the
shell, straight, divergent ; their inner half thinner, cylindrical, smooth, their outer half an ovate
dimpled cone.

Dimensions. — Shell 01 long, 013 broad ; horn and feet 0'06 long.

Habitat. — Indian Ocean, Cocos Islands (Eabbe), surface.

15. Tripospyris tribrachiata, Haeckel.

Cladospyris tribrachiata, Ehrenberg, AbhandL d. k. Akad. d. Wiss. Berlin, p. 68, Tai xxi.
fig. 8.

Shell subspherical, smooth, with slight sagittal stricture and numerous, very small circular
pores. Basal plate with numerous small pores. Apical horn and the three divergent feet very
large and stout, straight, three-sided prismatic, with dentate edges, two to three times as long as
the shell.

Dimensions. — Shell diameter 0'05 ; horn and feet 01 to 015 long.

Habitat. — Fossil in Barbados.

16. Tripospyris furcata, n. sp. (PL 83, fig. 11).

Shell nut-shaped, smooth, with deep sagittal stricture and broad ring. Basal plate with three
pairs of small pores. Facial and occipital faces each with a pair of very large holes. Apical horn
and caudal foot simple conical, two pectoral feet forked or irregularly branched.

Dimensions. — Shell 0'08 long, 012 broad ; horn and feet O'Oo long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 442. Triceraspyris,1 Haeckel, 1881, Prodromus, p. 441.
Definition. — Z ygospyrida with three basal feet and three coryphal horns.

The genus Triceraspyris has arisen from the preceding ancestral Tripospyris by the
development of two paired frontal horns, so that the shell here bears six appendages,

1 Triceraspyris = Basket with three horns ;

1030 THE VOYAGE OF H.M.S. CHALLENGER.

three superior or coryphal spines and three inferior or basal spines ; two of these are odd
and dorsal (the apical horn and the caudal foot), the four others are paired and ventral
(the frontal horns and the pectoral feet). The numerous species of this genus may be
divided into three subgenera, according to the simple or branched shape of the ascending
liorns and of the descending feet.

Subgenus 1. Triospyris, Haeckel, 1881, Prodromus, p. 441.
Definition. — Horns and feet simple, not branched nor forked.

1. Triceraspyris tripodiscus, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish, two pairs of
larger pores on each side of the ring. Basal plate with three large pores. Horns and feet slender
cylindrical, straight, divergent ; three horns about as long as the shell, three feet twice as long.

Dimensions. — Shell 0'06 long, 008 broad ; horn O'Oo long, feet 01.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

2. Triceraspyris cortiniscus, n. sp.

Shell subspherical, smooth, with slight sagittal stricture. Pores small and numerous, subregular
roundish. Basal plate with two large pores (?). Apical horn conical, short, half as long as the
shell and the two lateral horns, which are curved outwards. All three feet equal, cylindrical,
strongly curved and divergent, twice to three times as long as the shell.

Dimensions. — Shell 0'07 long, 0'08 broad ; horn 0'04 to 0'08 long, feet 015 to 0'2 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Triceraspyris didiceros, Haeckel.

Ceratospyris didiceros, Ehrenberg, 1875, Abhandl. d. Akad. d. Wiss. Berlin, p. 66, Taf. xxi.
fig. 6.

Shell nut-shaped, thorny, with superficial sagittal stricture. Pores large, irregular roundish.
Basal plate with four larger pores. Apical horn and caudal foot small, conical, shorter than half
the shell. The two frontal horns longer, slender conical. The two pectoral feet very large,
cylindrical, nearly parallel, vertical, slightly curved, twice to three times as long as the shell.

Dimensions. — Shell 0'07 long, 0'09 broad; two sagittal spines 0'02 long, two lateral horns
0-04 long, two lateral feet 015 to 0'25 long.

Habitat. — Fossil in Barbados.

Subgenus 2. Triospyrium, Haeckel.
Definition. — Horns simple, not branched ; feet forked or branched.

REPORT ON THE RADIOLARIA. 1031

4. Triceraspyris furcata, Haeckel.

Ceratospyris furcata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.
fig. 8.

Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores numerous, irregular roundish.
Basal plate with four large pores. Three horns small, conical, shorter than half the shell. Three
feet large, cylindrical, curved, about twice as long as the shell, forked at the distal end.

Dimensions. — Shell 0'07 long, 0'08 broad ; horns 0'02 long, feet 01 to 012 long.

Habitat. — Fossil in Barbados.

5. Triceraspyris giraffa, n. sp. (PL 84, fig. 11).

Shell nut-shaped, mammillate, with slight sagittal stricture. Pores numerous, subregular circular.
Basal plate with nine pores (three larger central and three alternate pairs of smaller peripheral, as in
PI. 87, fig. 2). Three horns equal straight, divergent, shorter than the shell, in the basal half
cylindrical, in the distal half spindle-shaped. Three feet cylindrical, twice as long as the shell,
nearly parallel, vertical, at the distal end divergent, with a recurved branch near the base.

Dimensions. — Shell 0'08 long, 01 broad ; horns 0'05 to 0'07 long, feet 016 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

6. Triceraspyris gazella, n. sp. (PI. 84, fig. 9).

Shell nut-shaped, tuberculate, with sharp sagittal stricture. Pores large, irregular roundish ;
two or three pairs of larger pores on each side of the ring. Basal plate with three large triangular
pores. Three horns simple, about as long as the shell, the apical straight, the two frontal elegantly
curved. Three feet somewhat longer, slender, curved, with a recurved branch near the base,
repeatedly forked at the distal end.

Dimensions. — Shell 0'06 long, 0'09 broad ; horn 0'05 long, feet 0'08 long.

Habitat. — Indian Ocean (Cocos Islands), surface (Eabbe).

7. Triceraspyris corallorrhiza, n. sp. (PI. 84, fig. 12).

Shell nut-shaped, spiny, with deep sagittal stricture. Pores irregular polygonal or roundish.
Basal plate with two large semicircular pores. Three horns slender, simple, about half as long as
the shell. Three feet of the same length, slender, divergent, irregularly branched like coral.

Dimensions. — Shell 0'06 long, 0'09 broad ; horn and feet 0'03 to 0'05 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

8. Triceraspyris manicidata, n. sp.

Shell subspherical, smooth, without external sagittal stricture. Pores subregular circular.
Basal plate with four large pores (?). Three horns simple, straight, divergent, spindle-shaped, half

1032 THE VOYAGE OF H.M.S. CHALLENGER.

as long as the shell. Caudal foot of the same form, twice as long. Two pectoral feet cylindrical,
curved, twice as long as the shell, palmate, divided at the distal end into five short fingers.

Dimensions. — Shell 0'08 diameter ; horns 0'04 long ; lateral feet 012 long.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

9. Triceraspyris longicornis, n. sp.

Shell nut-shaped, papillate, with deep sagittal stricture. Pores irregular roundish. Basal
plate with six pores (?). Apical horn short, conical, two frontal horns very large, curved, widely
divergent, longer than the shell. Three feet of about the same length, irregularly branched.

Dimensions. — Shell 0'08 long, 012 broad ; lateral horns and feet 015 to 0'2 long.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

Subgenus 3. Triospyridium, Haeckel.
Definition. — Horns and feet forked or branched.

10. Triceraspyris damaecornis, n. sp.

Shell nut-shaped, smooth, compressed, with broad sagittal ring. Pores irregular roundish ; one
pair of very large pores on each side of the ring. Basal plate with four large collar pores. Three
horns and three feet short, divergent, slightly curved, about half as long as the shell, irregularly
branched. (In general form very similar to Elaphospyris damaecornis, PL 84, fig. 10, with which I
formerly confounded it.)

Dimensions. — Shell 0'08 long, 012 broad ; horns and feet 0'04 long.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

11. Triceraspyris arborescens, n. sp.

Shell subspherical, with deep sagittal stricture. Pores irregular roundish ; three pairs of larger
pores on both sides of the ring. Basal plate with two large collar pores. Three horns about half
as long as the shell, with few irregular terminal branches. (Beginning of a cupola.) Three feet
strong, cylindrical, twice as long as the shell, richly branched, arborescent.

Dimensions. — Shell 0'09 long, 01 broad ; horns 0'05 long, feet 0'2 long.

Habitat. — Indian Ocean (Madagascar), Kabbe, surface.

Genus 443. Tristylospyris,1 Haeckel, 1881, Prodromus, p. 441.
Definition. — Zygospyrida with three basal feet, without apical horn.

The genus Tristylospyris exhibits in general the same structure as the typical genus
Tripospyris, its ancestral form. It differs from the latter in the absence of the apical

1 Tristylospyris— Basket with three styles;

REPORT ON THE RADIOLARTA. 1033

horn, which is completely reduced, and may therefore be regarded as the simplest
prototype of all tripodal Cyrtellaria without a horn.

Subgenus 1. Tristylospyrula, Haeckel.

* .
Definition. — Feet simple, not branched nor forked.

1. Tristylospyris palmipes, n. sp. (PI. 84, fig. 14).

Shell companulate, smooth, with slight sagittal stricture. Pores irregular roundish, three pairs
of larger annular pores on each side of the broad ring. Basal plate with four large collar pores.
Feet half as long as the shell, slightly divergent, straight, prismatic, with a broad, hand-like, radially
striped plate at the distal end.

Dimensions. — Shell O'l long, O09 broad ; feet 0'06 long.

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

2. Tristylospyris scaphipes, n. sp. (PI. 84, fig. 13).

Shell nut-shaped, smooth, with sharp sagittal stricture. Pores very small and numerous,
circular ; two pairs of larger pores on both sides of the ring. Basal plate with four large pores (?).
Feet about half as long as the shell, angular, shovel-shaped, straight, parallel, vertical.

Dimensions. — Shell 0'06 long, 0'08 broad ; feet 0'04 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

3. Tristylospyris clavipes, n. sp. (PL 84, fig. 15).

Shell nut-shaped, rough, with deep sagittal stricture. Pores small, subregular circular. Basal
plate with three large pores. Feet about as long as the shell, slender, straight, divergent, with a
spinulate knob at the thickened distal end.

Dimensions. — Shell 0'06 long, 0'08 broad ; feet 0'05 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Tristylospyris triceros, Haeckel.

Ceratosjjyris triceros, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xxi.
fig. 5.

Shell nut-shaped, tuberculate, without external sagittal stricture. Pores circular, not numerous,
Basal plate with four large collar pores. Feet large, cylindrical, three to four times as long as the
shell, strongly curved and divergent.

Dimensions. — Shell 0'05 long, 0'07 broad ; feet 015 to 0'2 long.

Habitat. — Fossil in Barbados.

(ZOOL. CHALL. EXP. PART XL. — 1836.) Rr 130

1034 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 2. Tristylospyrium, Haeckel.
Definition. — Feet forked or branched.

5. Tristylospyris furcata, n. sp.

Shell subspherical, rough, with slight sagitta stricture. Pores subregular circular. Basal plate
with three large collar pores. Feet cylindrical, three to four times as long as the shell, strongly
curved and divergent, at the distal end forked, with two short (sometimes ramified) branches.

Dimensions. — Cephalis 0'08 long, 0'09 broad ; feet O2 to 0'3 long.

Habitat. — South Atlantic (off Patagonia), Station 318, surface.

6. Tristylospyris ramosa, n. sp. (PI. 52, fig. 23).

Shell subspherical, tuberculate, with a prominent sagittal ring. Pores irregular roundish.
Basal plate with three large pores. Feet large, straight, widely divergent, about twice as long as
the shell, prismatic, irregularly branched. (Compare the following species.)

Dimensions. — Shell 0'08 in diameter ; feet 0'15 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

7. Tristylospyris tripodiscium, n. sp. (PI. 52, fig. 22).

Shell subovate, tuberculate, very similar to the preceding species. It differs from this in the
very different size of the irregular pores and the greater breadth of the pedal branches. The basal
plate in a complete specimen (observed afterwards from the base) exhibited four large collar pores
of the usual form, whilst in the similar preceding species it had three pores. In the similar
Tripodiscium sphcerocephalum (PI. 52, fig. 21) the basal mouth is quite simple and open.

Dimensions. — Shell 0'09 long, O'l broad ; feet 012 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 444. Cephalospyris,1 Haeckel, 1881, Prodromus, p. 441 (sensu emend.}.

Definition. — Z ygospyrida with three basal feet and two large apical openings
or coryphal holes, one on each side of the ring-apex. No true horns.

The genus Cephalospyris comprises some few Tripospyrida of very peculiar shape,
differing from all other Zygospyrida in the possession of two large apical holes or
coryphal apertures, lying on each side of a latticed sagittal septum, which is formed
by the upper part of the sagittal ring. The sagittal stricture is deep, with a complete

1 Cephalospyris = Head-like basket ;

REPORT ON THE RADIOLARIA. 1035

primary ring. The vertical axis of the slender ovate shell is much greater than the
transverse. The network is very delicate, with very small and numerous triangular
or polygonal pores. The central capsule encloses peculiar concrements (PI. 96, fig. 28).

1. Cephalospyris cancellata, n. sp. (PI. 83, fig. 10).

Shell slender ovate, two and a half times as long as broad, with deep sagittal stricture and
complete ring. Network very delicate, with very small and numerous, irregular polygonal pores.
The two large apical holes are separated by a latticed triangular sagittal septum, the apex of which
represents a rudimentary horn. Basal plate with two large collar holes. Three feet slightly
curved, divergent, about half as long as the breadth of the shell ; the caudal foot slender, mucli
thinner than the two stout pyramidal pectoral feet.

Dimensions. — Shell 0'32 long, 013 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Cephalospyris ovata, n. sp.

Shell slender, ovate, twice as long as broad, with deep sagittal stricture and complete ring.
Network very delicate, with very small and numerous triangular pores (on both poles intermingled
with irregular polygonal pores). The two large apical holes are separated by a latticed triangular
sagittal septum, the upper edge of which is concave and bears two rudimentary horns. Basal plate
with four large collar holes. Three feet latticed, slightly curved, convergent, scarcely one-eighth as
long as the breadth of the shell. The central capsule filled up by concrements.

Dimensions. — Shell 0'32 long, 0'16 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Cephalospyris triangulata, n. sp. (PL 96, fig. 28).

Shell ovate, one and a half times as long as broad, with deep sagittal stricture and complete
ring. Network very delicate and regular, with small triangular pores of equal size. The two lar^e
apical holes are separated by a latticed semilunar septum, the upper edge of which is concave, and
bears two rudimentary horns. Basal plate with three large collar holes (?). Three feet latticed,
conical, nearly parallel and vertical (the caudal curved), about half as long as the breadth of the
shell. The ovate central capsule contains peculiar amyloidal concentric concrements.

Dimensions. — Shell 0'2 long, 0'14 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Subfamily 2. DIPOSPYRIDA, Haeckel, 1881, Prodromus, p. 441.

Definition. — Zygospyrida dipoda, with two descending lateral basal feet
(probably corresponding to the pectoral feet of Cortina}.

1036 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 445. Dipospyris,1 Haeckel, 1881, Prodromus, p. 441.

Definition. — Z ygospyrida with two simple free basal feet and one apical
horn.

The genus Dipospyris and the following five, genera represent together the interesting
subfamily of Dipospyrida, which always bear two opposite lateral feet only. Therefore
in this bipedal group the biradial or bilateral type of the Spyroidea is particularly
expressed. Such bipedal forms never occur in the Cyrtoidea. The topographical
relation of the two lateral feet to the rods of the collar-plate, and to the cortinar pores
separated by these, leaves no doubt that they correspond to the pectoral feet of
Cortina and Tripospyris, and therefore that the Dipospyrida have originated from the
Tripospyrida by loss of the caudal foot. Dipospyris is the simplest form of the Dipo-
spyrida, with two simple free feet.

1. Dipospyris bipes, n. sp.

Shell thorax-shaped, smooth, with deep sagittal stricture, two vaulted bosoms, and subregular
circular pores. Basal plate with two large collar pores only. Horn and feet equal, conical, straight,
about as long as the shell ; the feet widely divergent.

Dimensions. — Shell 0'08 long, 012 broad ; horn and feet 01 to 015 long.

Habitat. — Fossil in Barbados.

2. Dipospyris mystax, Haeckel.

Ceratospyris mystax, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 60, Taf. xx. tig. 6.

Shell elliptical spiniilate, with slight collar stricture and large subregular circular pores.
Basal plate with three pores (?) Horn small conical, oblique, shorter than the shell. Feet
slender conical, longer than the shell, slightly curved, divergent. At the base of the columella,
between the two feet, a small rudiment of the last caudal foot is visible.

Dimensions. — Shell 0'06 long, 01 broad ; horn 0'02, feet 012 long.

Habitat. — Fossil in Barbados.

3. Dipospyris cubus, n. sp. (PL 83, fig. 18).

Shell box-shaped, subcubical, papillate, without external sagittal stricture, with numerous
subregular circular pores. Basal plate with three very large collar pores, surrounded by a circle of
smaller pores. Apical horn short and thick, scarcely half as long as the shell. Feet of the same
form, longer than the shell, widely divergent.

Dimensions. — Shell 0'08 long, Oil broad ; horn 0'03 long, feet 014 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

1 Dipospyrls = Basket with two i'eet ; SiVoi/f, cvvgi;.

REPORT ON THE RADIOLARIA. 1037

4. Dipospyris chelifer, n. sp. (PI. 85, fig. 3).

Shell elliptical, compressed, nodose, with deep sagittal stricture aud irregular roundish pores.
Basal plate with three pores (?). Apical horn stout, conical, twice to four tunes as long as the shell
(often much longer than in the figured specimen). Feet scarcely longer than the shell, cylindrical,
slightly curved towards one another.

Dimensions. — Shell 0'08 long, 012 broad; horn 0'2 to 0'3 long, feet 01 to 015 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

5. Dipospyris irregularis, n. sp.

Shell subspherical, without external sagittal stricture, with small circular pores. Basal plate
with four pores. Apical horn small, conical, shorter than the shell. Feet three to four times as
long as the shell, cylindrical, irregularly curved, very variable in size and form.

Dimensions. — Shell 0'08 long, 01 broad ; horn 0'02 to 0'04 long, feet 0'2 to 0'3 long.

Habitat. — Central Pacific, Stations 266 to 268, depth 2700 to 2900 fathoms.

6. Dipospyris sigmopodium, n. sp.

Shell violin-shaped, thorny, with deep sagittal stricture and irregular roundish pores. Basal
plate with four collar pores. Horn straight, conical, about as long as the shell. Feet twice as long,
cylindrical, markedly divergent, S-shaped, curved.

Dimensions. — Shell 0'08 long, 012 broad ; horn 0'06 long, feet 0'2 long.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms ; also fossil in Barbados.

7. Dipospyris for cipata, n. sp. (PI. 85, fig. 1).

Shell nut-shaped, tuberculate, with subregular circular pores. Basal plate with four larger and
a circle of six to ten smaller pores. Horn cylindrical, straight, two to three times as long as the
shell. Feet three to five times as long as the shell, cylindrical, semicircular, with convergent and
crossed distal ends. (If these ends grow together, Gamospyris arises.)

Dimensions. — Shell 0'08 long, Oil broad ; horn 015 to 0'2 long, feet 0'2 to 0'4 long.

Habitat. — Central Pacific, Stations 263 to 268, depth 2600 to 3000 fathoms.

Genus 446. Brachiospyris,1 Haeckel, 1881, Prodromus, p. 441.

Definition. — Zygospyrida with two simple free basal feet, without apical
horn.

The genus Brachiospyris differs from the preceding Dipospyris, its ancestral form,
only" in the absence of the reduced apical horn, and therefore bears to it a similar

1 Brachiotyyrix= Basket with two arms; fl^a^iuu,

1038 THE VOYAGE OF H.M.S. CHALLENGER.

relation to that which the hornless Tristylospyris, among the Tripospyrida, bears to the
horned Tripospyris. Brachiospyris may therefore also be derived from Tristylospyris
by loss of the caudal foot.

1. Brachiospyris ocellata, Haeckel.

Ceratospyris ocellata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx
fig. 5.

Shell nut-shaped, thorny, with slight sagittal stricture and irregular roundish pores. Basal
plate with four large and four .alternate pairs of smaller pores. Two feet cylindrical, straight,
divergent, two to three times as long as the shell.

Dimensions. — Shell 0'08 long, Oil broad: feet 0'2 to 0'3 long.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms ; also fossil in Barbados.

2. Brachiospyris diacantha, n. sp. (PI. 95, fig. 5).

? Ceratospyris diacantha, Ehrenberg, 1872, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 303.

Shell nut-shaped, tuberculate, compressed in the sagittal axis, convex on the frontal face, concave
on the sagittal face, with a slight sagittal stricture ; with large irregular roundish pores. Basal
plate with three very large pores. Two feet cylindrical, curved, S-shaped, about twice as long as
the shell.

Dimensions. — Shell 0'06 long, 0'09 broad ; feet 01 to 015 long.

Habitat. — Western Tropical Pacific (Philippine Sea), Station 206, depth 2100 fathoms.

Genus 447. Dendrospyris,1 Haeckel, 1881, Prodromus, p. 441.

Definition. — Z ygospyrida with two free lateral feet, forked or branched like
a tree. Apex with a horn.

The genus Dendrospyris differs from its ancestral form Dipo^yris in the
ramification of the two large lateral feet, which descend from the base of the shell, and
are usually very large and stout, sometimes simply forked.

1. Dendrospyris stylophora, Haeckel.

Ceratospyris stylophora, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.
fig. 10.

Shell nut-shaped, thorny, with subregular circular pores. Basal plate with four pores. Apical
horn and the two divergent feet straight, cylindrical, larger than the shell, forked at the distal end.

1 Dendrospyris -- Basket with arborescent feet ; aii/toon, ovvgls.

REPORT ON THE RADIOLARIA. 1039

(The size and number of the fork-branches is variable ; the horn is sometimes simple. In some
specimens a rudimentary remnant of the lost caudal foot is visible.)

Dimensions. — Shell 0'08 long, 0'09 broad; horn and feet 01 to 012 long.

Habitat. — Fossil in Barbados.

2. Dendrospyris dirrhiza, Haeckel.

Geratospyris dirrhiza, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.
fig. 9.

Shell nut-shaped, spiny, very similar to the preceding species. It differs from that mainly in
the growth of the cylindrical feet, which are not straight and divergent, but more or less curved
and convergent ; their distal ends are sometimes simply forked, sometimes repeatedly dichotomous.
The size and form of the apical horn are also very variable.

Dimensions. — Shell O'OG long, 0'08 broad ; horn and feet 0'07 to 0'09 long.

Habitat. — Fossil in Barbados.

3. Dendrospyris bibrachiata, Haeckel.

Cladospyris Mlracliiata, Ehrenberg, 1 875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. xxi.

fig. 7.

Shell nut-shaped, smooth, with sharp stricture and numerous very small circular pores. Apical
horn and the two feet very large and stout, straight, prismatic, with irregular lateral branches on
their edges, twice to four times as long as the shell. (The horn in the Ehrenberg's figure is
broken off.) This species is closely allied to Tripospyris tribrachiata.

Dimensions. — Shell O05 long, 0'06 broad ; horn and feet O'l to 0'2 long.

Habitat. — Fossil in Barbados.

4. Dendrospyris furcata, n. sp.

Shell subspherical, tuberculate, with irregularly roundish pores. Basal plate with two large pores.
Apical horn simple, conical, as long as the shell. Feet cylindrical, twice as long, in the proximal
half parallel, vertical, in the distal half with two stout divergent equal fork-branches, one of which
is directed dorsally, the other ventrally.

Dimensions. — Shell O'OT long, 0'08 broad ; horn 0'06 long, feet 01 to 015 long.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

5. Dendrospyris polyrrhiza, 11. sp. (PI. 85, fig. 8).

Shell subspherical, rough, with subregular circular pores. Basal plate with three pores (?).
Apical horn simple, conical, half as long as the shell. Feet cylindrical twice to three times as long
as the shell, semicircular, with a strong conical tooth in the middle of their outer convex edge ;
their distal ends convergent, divided into a bunch of numerous short irregular branches.

Dimensions. — Shell 0'7 long, 0'08 broad ; horn 0'03 long, feet 015 to 0'25 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

1040 THE VOYAGE OF H.M.S. CHALLENGER.

6. Dendrospyris ramosa, n. sp.

Shell nut-shaped, spiny, with irregular roundish pores. Basal plate with three pairs of pores.
Apical horn cylindrical, spinulate, twice to three times as long as the shell. Feet as long as the
horn, S-shaped, widely divergent, irregularly branched, with widely distant pointed branches.

Dimensions. — Shell 0'08 long, 012 broad ; horn and feet 0'2 to 0'3 long.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

7. Dendrospyris arborescens, n. sp. (PI. 85, fig. 9).

Shell nut-shaped, tuberculate, with subregular circular pores. Basal plate with four central
larger and ten to twelve peripheral smaller pores. Apical horn cylindrical, twice as long as the
shell, in the distal half spinulate or tuberculate. Feet about three times as long as the shell,
cylindrical, nearly vertical, in the distal half irregularly branched, with dense bunches of aggregated
blunt branches.

Dimensions. — Shell 0'07 long, 0'09 broad ; horn and feet 012 to 018 long.

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

Genus 448. Dorcadospyris,1 Haeckel, 1881, Prodromus, p. 441.

Definition. — Zy go spy rid a with two free lateral feet armed with a series of
secondary spines. Apex with a horn.

The genus Dorcadospyris and the closely allied Stephanospyris differ from the other
Dipospyrida in the development of a series of secondary spines on the convex outer margin
of the two large curved lateral feet, which therefore appear semipinnate. In some species
this peculiar armature attains an extraordinary size, whilst the shell itself is very small,
as in Dorcadospyris dinoceras (PI. 85, fig. 4).

1. Dorcadospyris dentata, n. sp. (PI. 85, fig. 6).

Shell subspherical, tuberculate, with small regular circular pores. Basal plate with four larger
pores. Apical horn three to four times as long as the shell, slender, conical, smooth. Feet more
or less convexly curved towards one another ; the distal ends not crossed. In the convex edge of
each arm a series of five to ten smooth conical teeth, not longer than the shell. This common
species is very variable and often asymmetrical ; the figured specimen is an asymmetrical one, in
which the two arms exhibit different curves ; in the normal form both arms have the same curve,
now more, now less convex.

Dimensions. — Shell 0'06 long, 0'08 broad ; horn 0'2, feet 0'03 long.

Habitat. — Central Pacific, Stations 267 to 274, depth 2350 to 2925 fathoms.

1 Dorcadospyris = Basket with two horns, similar to an antelope ; Sojxa?, awi/j/f.

REPORT ON THE RADIOLARIA. 1041

2. Dorcadospyris antilope, n. sp. (PI. 85, fig. 5).

Shell subspherical, tuberculate, with small regular circular pores. Basal plate with four larger
pores. Apical horn four to six times as long as the shell, straight, cylindrical, smooth. Feet of
the same length, crescentic or nearly semicircular, with crossed distal ends. On the convex edge
of each foot a series of twelve to fifteen smooth conical teeth, partly longer than the shell.
(Very variable in size and curvature of the feet, and number of their teeth.)

Dimensions. — Shell 0'09 long, Oil broad ; horn and feet 04 to 0'6 long.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

3. Dorcadospyris lunulata, n. sp.

Shell subspherical spinulate, nearly of the same shape as in the preceding species, but with a
short conical horn (scarcely as long as the shell); the feet are much more slender, crescentic, and
bear twenty to thirty smaller smooth conical teeth (shorter than the shell). The distal ends of the
feet are crossed.

Dimensions.— Shell 0'08 long, 0'09 broad ; horn 0'06 long, feet 0'03 to 0'06 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

4. Dorcadospyris decussata, n. sp. (PI. 85, fig. 7).

Shell subspherical, smooth, very similar to that of the two preceding species. Horn small conical,
about as long as the shell. Feet more than semicircular, more strongly curved than in any other
species, each with four to eight small conical teeth, shorter than the shell ; distal ends crossed.
(In this species also, besides the normal symmetrical form, there often occurs an asymmetrical
form of the two feet ; one of these frequent anomalies is shown in fig. 7.)

Dimensions. — Shell 0'06 long, 0'08 broad ; horn O'Oo, feet 0'2 to 0'5 long.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

5. Dorcadospyris dinoceras, n. sp. (PI. 85, fig. 4).

Shell subspherical, tuberculate, with subregular circular pores. Basal plate with four larger
central and eight to twelve smaller peripheral pores. Horn about as long as the shell, in the basal
half prismatic, smooth, in the distal half ovate or strobiliform, spiny. Feet very large and strongly
curved, together nearly heart-shaped, four to six times as long as the shell. Each foot bears on
its outer convex side a series of fifteen to twenty or more strong conical teeth, which are again
spinulate, perpendicular to the foot, and longer than the shell.

Dimensions. — Shell 0'08 long, 0'09 broad ; horn 0'07 long, feet 0'3 to 0'5 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

(ZOOL. CHALL. BXP. — PART XL. — 1886.) Rr 131

1042 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 449. Gamospyris,1 Haeckel, 1881. Prodromus, p. 441.
Definition. — Z ygospyrida with two simple lateral feet, forming a ring by union.

The genus Gamospyris and the similar Stephanospyris differ from all other
Spyroidea in the possession of a large basal ring, placed in the frontal plane of the
shell. This ring has been produced by concrescence of the distal ends of the two large
curved lateral feet of Dipospyris.

1. Gamospyris circulus, n. sp. (PL 83, fig. 19).

Shell subspherical, tuberculate, with subregular circular pores. Basal plate with four larger
collar pores. Apical horn pyramidal, about as long as the shell. The connected feet form
together a circular or nearly circular smooth ring, the diameter of which is three to four times as
great as that of the shell.

Dimensions. — Shell 0'08 long, 0'09 broad ; diameter of the arm-ring 0'25 to 0%33.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Gamospyris annulus, n. sp.

Shell nut-shaped, tuberculate, with subregular circular pores. Basal plate with four large
central and a circle of eight to twelve small peripheral pores. Apical horn conical, twice as long as
the shell. The connected arms form together an elliptical smooth ring, which is five times as long
and three times as broad as the shell.

Dimensions. — Shell 0'07 long, 0'09 broad ; ring 0'33 long, 0'26 broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 450. Stephanospyris? Haeckel, 1881, Prodromus, p. 441.

Definition. — Z ygospyrida with two lateral feet bearing a series of secondary
spines and forming a ring by union.

The genus Stephanospyris exhibits the same peculiar armature of the semipinnate
lateral feet as its ancestral genus Dorcadospyris, but differs from it in the concrescence
of the distal ends of the feet, to form a complete foot-ring. The former therefore bears
to the latter the same relation that Gamospyris does to Dipospyris.

1. Stephanospyris cordata, n. sp. (PL 85, fig. 10).

Shell subspherical, tuberculate, with small regular circular pores. Basal plate with four
larger pores. Apical horn cylindrical, three times as long as the shell, with three to four verticils

1 Gamospyris = Basket with two feet grown together ; ydfto(, vitv^k-

2 Stephanospyris = Basket with a garland ; <rr«<p«»of, awtf; .

REPORT ON THE RADIOLARIA. 1043

of teeth. The connected feet form a heart-shaped ring, four times as long and three times as
broad as the shell. Each foot bears on the outer convex edge four to six stout conical teeth,
shorter than the shell. Distal ends crossed and prominent.

Dimensions. — Shell diameter 01 ; length of the arm-ring 0'4, breadth 0'3.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Stephanospyris verticillata, n. sp. (PI. 85, fig. 11).

Shell nut-shaped, tuberculate, with subregular circular pores. Basal plate with numerous
small pores. Apical horn cylindrical, four to six times as long as the shell, with six to ten
verticils of teeth. The connected feet form a circular ring, the diameter of which is four times
as great as that of the shell. Each foot bears ten to twelve conical teeth, about as long as the
shell. Distal ends not crossed and not prominent.

Dimensions. — Diameter of the shell 01, of the arm-ring 04.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Stephanospyris excellens, n. sp. (PL 83, fig. 20).

Shell subspherical, tuberculate, with regular circular pores. Basal plate with numerous small
pores. Apical horn cylindrical, twice as long as the shell, with eight verticils of teeth. The
connected feet form an ovate ring, which is three times as long and two and a half times
as broad as the shell. Each foot bears eight conical spinulate teeth, about as long as the shell.
The crossed and prominent distal ends bear two parallel vertical teeth.

Dimensions. — Diameter of the shell 01, of the arm-ring 0'2 to 0'3.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Subfamily 3. TETRASPYRIDA, Haeckel, 1881, Prodromus, p. 442.

Definition. — Z ygospyrida tetrapoda, with four descending basal feet, two of which
are opposite in the sagittal plane (an odd caudal and an odd sternal foot), whilst the two
others are paired lateral or pectoral feet.

Genus 451. Tetraspyris? Haeckel, 1881, Prodromus, p. 442.

Definition. — Z ygospyrida with four basal feet crossed in pairs (two sagittal and
two lateral). Apex with a horn.

The genus Tetraspyris and the following closely allied Tessarospyris represent
together the small subfamily of Tetraspyrida, characterised by the possession of four
descending basal feet, three of which correspond to the three original feet of the

1 Tetraspyris = Basket with four feet ; TITJK, usri/f If.

1044 THE VOYAGE OF H.M.S. CHALLENGER.

ancestral genera Cortina and Tripospyris, whilst the fourth is an odd anterior or sternal
foot, produced by anterior prolongation of the basilar segment of the sagittal ring. Here,
therefore, two opposed feet lie in the sagittal plane (a caudal and a sternal foot), whilst
the two others are the paired lateral or pectoral feet, as also in Stephanium and
Stephaniscus, p. 965. The Tetraspyrida ought not to be confounded with the
Therospyrida (sixth subfamily), in which the four feet have another signification.

Subgenus 1. Tetrarrhabda, Haeckel, 1881, p. 429.
Definition. — Feet simple, not branched nor forked.

1. Tetraspyris stephanium, n. sp. (PI. 95, fig. 6).

Shell nut-shaped, tuberculate, with deep sagittal stricture and small roundish pores ; three
pairs of larger pores on each side of the ring. Basal plate with four large collar pores. Apical
horn stout conical, half as long as the shell. Two pectoral feet somewhat longer than the two
sagittal feet, .one and a half times as long as the shell. All four feet straight, three-sided
prismatic, strongly divergent.

Dimensions. — Shell 008 long, 012 broad ; horn 0'04 long, feet 0'08 to 012 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Tetraspyris cubica, n. sp.

Shell nearly cubical, smooth, with slight sagittal stricture and small polygonal pores ; some
larger pores on both sides of the ring. Basal plate with four large collar pores. Apical horn
and the four feet of equal size and form, about as long as the shell, cylindrical in the basal,
spindle shaped in the distal half.

Dimensions. — Shell 0'09 diameter ; horn and feet 01 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; also fossil in Barbados.

Subgenus 2. Tetracorethra, Haeckel, 1881, Prodromus, p. 429.
Definition. — Feet branched or forked.

3. Tetraspyris tetracorethra, n. sp. (PI. 53, figs. 19, 20).

Tetracorethra miraUlis, Haeokel, 1881, Prodromus, p. 429, and Atlas, loc. cit.

Shell campanulate, tuberculate, with deep sagittal stricture and irregular polygonal pores ; two
pairs of larger pores at the flattened occipital face (fig. 20). Basal plate with four large collar
pores. Apical horn very long, thirty to forty times as long as the shell, slender three-sided
prismatic, straight, at the distal end irregularly branched, besom-shaped. Four basal feet half as

REPORT ON THE RADIOLARIA. 1045

thick as the horn, eight to twelve times as long as the shell, bristle-shaped, irregularly curved and
branched, divergent, at the distal end besom-shaped. Central capsule very large; the enclosed
small campanulate part sends out through the four collar pores four very long club-shaped basal
lobes, half as long as the feet ; each lobe contains a large oil-globule (fig. 19).

Dimensions. — Shell 0'036 diameter ; horn 1 to T5 mm. long, feet 0'3 to 0'4 long.

Habitat. — Central Pacific, Station 270, surface.

4. Tetraspyris calcarata, n. sp.

Shell campanulate, smooth, very similar to that of the preceding species, but differing in the follow-
ing characters : — the two inferior occipital pores are four times (in the preceding twice) as large as
the two superior; the apical horn bears at its distal end only three simple branches; the sternal foot
is smaller than the three others, arises higher, is more divergent and curved, and bears at its base
a large horizontal conical spur.

Dimensions. — Shell 0'035 diameter ; horn 1 to 1'2 long, feet 0'2 to 0'3 long.

Habitat. — Central Pacific, Station 266, surface.

5. Tetraspyris scoparia, n. sp.

Shell campanulate, rough, very similar to the two preceding species, but differing in the
following characters : — the four occipital pores are of nearly equal size ; the apical horn is simple, not
branched ; the four feet are forked near the base, so that apparently eight feet diverge, each in the
distal half richly branched, besom-shaped.

Dimensions. — Shell 0'038 diameter ; horn 1 to 11 long, feet 0'4 to 0'5 long.

Habitat. — Central Pacific, Station 268, surface.

Genus 452. Tessarospyris,1 Haeckel, 1881, Prodromus, p. 442.

Definition. — Z ygospyrida with four basal feet crossed in pairs (two sagittal and
two lateral). Apex without horn.

The genus Tessarospyris differs from the preceding Tetraspyris, its ancestral genus,
in the absence of the apical horn, and therefore bears to it the same relation that
Tristylospyris does to Tripospyris.

1. Tessarospyris clathrobursa, n. sp. (PI. 53, fig. 8).

Clathrobursa dictyopus, Haeckel, 1881, Prodromus, p. 429, and Atlas, pL liii. fig. 8.

Shell nearly ovate, strongly compressed, smooth, one and a half times as long as broad, with
deep sagittal stricture in the basal half. Pores very small and numerous, irregularly roundish. Basal
plate with four very large triangular holes, two larger (posterior) cardinal, and two smaller (anterior)

1 Tessarospyris = Basket with four feet ; •nuaa.^a,

1046 THE VOYAGE OF H.M.S. CHALLENGER.

jugular pores ; above the latter (on the frontal face) two large mental pores. Two pectoral feet
large, half as long as the shell, at the base fenestrated, vertical, and parallel. Two sagittal feet
much smaller, nearly horizontal, pyramidal (the caudal larger than the sternal foot). Two
longitudinal pectoral ribs arise on the frontal face.

Dimensions. — Shell 0'21 long, 014 broad ; lateral feet 01, sagittal feet 0'02.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

2. Tessarospyris nuciformis, n. sp.

Shell nut-shaped, papillate, with deep sagittal stricture. Pores irregular roundish, on both sides
of the ring three to six times as large as on the lateral sides. Basal plate with four large pores. Two
pectoral feet cylindrical curved, twice as long as the shell and as the two sagittal feet ; the caudal
is much stronger than the sternal foot.

Dimensions. — Shell 0'06 long, 0'09 broad ; lateral feet 01, sagittal feet O'Oo long.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

3. Tessarospyris seminulum, Haeckel.

Petalospyris seminulum, Stohr, 1880, Palseontogr., vol. xxvi. pL iii. fig. 12.

Shell subspherical, smooth, with slight sagittal stricture and small circular pores ; some larger
pores on both sides of the ring. Basal plate with two large (lateral) pores only. Four feet nearly
equal, short, conical, divergent, scarcely one-fourth as long as the shell.

Dimensions. — Shell 0'06 long, 0'08 broad; feet 0'016 long.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte), Stohr.

Subfamily 4. HEXASPYRIDA, Haeckel.

Definition. — Zygospyrida hexapoda, with six descending basal feet; three of
these are primary (one odd caudal and two paired pectoral feet), the other three are
secondary, opposed diametrically to the former and alternating with them (one odd
sternal and two paired tergal feet).

Genus 453. Hexaspyris,1 n. gen.
Definition. — Zygospyrida with six basal feet and one apical horn.

The genus Hexaspyris and the two following closely allied genera represent
together the peculiar subfamily of Hexaspyrida, and diifer from the other Zygospyrida
in the possession of six descending basal feet; three of these are the three original,
perradial, or primary basal feet of Cortina, Cortiniscus, Plagoniscus, Plectaniscus,
Tripospyris, &c. ; the other three, usually opposed to the former diametrically, are

1 Hexaspyris= Basket with six feet ; e£

REPORT ON THE RADIOLARIA. 1047

secondary or interradial; an odd sternal foot (opposed to the odd caudal) and two
paired tergal feet (opposed to the two paired pectoral).

Subgenus 1. Hexaspyridium, Haeckel.
Definition. — Feet simple, not branched nor forked.

1. Hexaspyris alterna, n. sp.

Shell nut-shaped, smooth, with deep sagittal stricture and irregular polygonal pores ; on each
side of the stricture two pairs of larger square annular pores. Basal plate also with four larger
collar pores. Apical horn twice as long as the shell, conical. Three primary feet (the apical and
the two pectoral) slender, curved, as long as the horn ; three secondary feet (the sternal and the
two tergal) are half as long as the former and more highly inserted ; all six feet strongly divergent,
cylindrical, pointed.

Dimensions. — Shell O06 long, 0'09 broad; horn 015 long, feet 0'08 to 014 long.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

2. Hexaspyris setigera, Haeckel.

Ceratospyris setigera, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.

fig. 11.
Ceratospyris setigera, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvL p. 539, Taf. xxxii-

figs, lla, 116.

Shell nut-shaped, tuberculate, with a complete internal sagittal ring and numerous small circular
pores. Basal plate with four larger central and a circle of twelve to twenty smaller peripheral
pores. Apical horn half as long as the shell, bristle-shaped. Three primary feet longer and more
deeply inserted than the three secondary feet; all six feet strongly divergent, bristle-shaped, shorter
than the shell.

Dimensions.— Shell 0'06 long, 0-09 broad ; horn 0'03 long ; primary feet 0'05, secondary
0-02 long.

Habitat. — Fossil in Barbados.

3. Hexaspyris butschlii, Haeckel.

Ceratospyris triomma, Biitsehli (non Ehrenberg), 1882, Zeitscbr. f. wiss. ZooL, voL xxxvi.
p. 539, Taf. xxxii. fig. 12, a, b.

Shell nut-shaped, spinulate, with a complete internal sagittal ring and subregular circular pores.
Basal plate with twelve pores (four larger central and eight smaller peripheral). Apical horn stout,
oblique, as long as the shell. Six feet of equal length, slightly divergent, nearly vertical, slender
three to four times as long as the shell.

Dimensions. — Shell 0'05 long, 0'07 broad ; horn 0'06, feet 015 to 0'2 long.

Habitat. — Fossil in Barbados.

1048 THE VOYAGE OF H.M.S. CHALLENGER.

4. Hexaspyris spinosa, Haeckel.

Petalospyris spinosa, Stohr, 1880, Palseontogr., vol. xxvi. p. 98, Taf. iii. fig. 14.

Shell subspherical, smooth, with slight sagittal stricture and irregular polygonal pores ; on
each side of the stricture two pairs of larger pores. Basal plate with two large pores only.
Apical horn short, pyramidal, three primary feet half as long as the shell and twice as long as the
three secondary feet. All six feet pyramidal, slightly divergent.

Dimensions.-^Shell 0'05 long, 0'07 broad ; horn 0'02, feet 0'02 to 0'04 long.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).

5. Hexaspyris ophirensis, Haeckel.

Petalospyris ophirensis, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. ix.
fig. 24.

Shell nut-shaped, with deep sagittal stricture and numerous irregular roundish pores ; two pairs
of larger pores on each side of the stricture. Apical horn short, curved. Six feet equal,
divergent, straight, slender, about as long as the shell.

Dimensions. — Shell 0'05 long, 01 broad; horn O'Ol, feet 0'05 to 0'08 long.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms, Pullen.

Subgenus 2. Hexacorethra, Haeckel.
Definition. — Feet forked or branched.

6. Hexaspyris hexacorethra, n. sp. (PI. 95, fig. 8).

Hexacorethra magica, Haeckel, 1882, Manuscript.

Shell campanulate, smooth, with sharp sagittal stricture and irregular roundish pores.
Basal plate with six larger collar pores. Apical horn very long and thin, three-sided prismatic,
straight, ten to twenty times as long as the shell, branched at the distal end. Six feet thinner,
bristle-shaped, six to eight times as long as the shell, divergent, irregularly curved, in the distal
part branched, besom-shaped ; the sternal foot at its base with a large conical horizontal spur.

Dimensions. — Shell 0'034 diameter ; horn 04 to 0'8 long, feet 0'2 to 0'3 long.

Habitat. — Central Pacific, Station 265, surface.

7. Hexaspyris articulata, Haeckel.

Ceratospyris articulata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.

%. 4.

Shell nut-shaped, tuberculate, with deep sagittal stricture and small irregular roundish pores.
Basal plate with six pores (?). Apical horn conical, longer than the shell. Six feet very large, thick

REPORT ON THE RADIOLARIA. 1049

cylindrical, divergent, three to four times as long as the shell, with few irregular lateral branches
(often much more developed than in Ehrenberg's figure).

Dimensions. — Shell 0'036 long, 0'05 broad ; horn 0'05, feet 01 to 015 long.

Habitat. — Fossil in Barbados.

Genus 454. Liriospyris,1 Haeckel, 1881, Prodromus, p. 443.
Definition. — Z ygospyrida with six basal feet and three coryphal horns.

The genus Liriospyris differs from the preceding Hexaspyris, its ancestral form,
in the possession of three coryphal horns (one odd apical in the middle, and two paired
frontal horns on each side of it); it therefore bears to the latter the same relation that
Triceraspyris does to Tripospyris.

1. Liriospyris hexapoda, n. sp. (PL 86, fig. 7).

Shell subspherical, smooth, with slight sagittal stricture and irregular roundish pores ; two to
three pairs of large annular pores on each side of the stricture. Basal plate with four large
collar pores. Three horns and six feet nearly of the same size and of similar form, conical, divergent,
about one-third as long as the shell.

Dimensions. — Shell diameter 0'09 to 01 ; horns and feet 0'03 to 0'04 long.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

2. Liriospyris dathrata, Haeckel.

Dictyospyris dathrus, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 25.

Dictyospyris dathrata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68,

Taf. xix. fig. 7.
Dictyospyris dathrata, Biitschli, 1882, Zeitschr. f. Wiss ZooL, voL xxxvi. pp. 506, 539 ;

Taf. xxxii. figs. 10a, 106.
Petalospyris duthrus, Haeckel, 1862, Monogr. d. Radio!., p. 295.

Shell campanulate or nearly spherical, smooth, with slight sagittal stricture. Three pairs of
large annular pores on each side of the stricture ; a few smaller irregular pores on the lateral sides.
Basal plate with six large collar pores (Biitschli, loc. cit., fig. 10a). Three horns and six feet nearly
of the same size and form; short, conical, slightly divergent or nearly parallel, shorter than half the
ring. (The size of the nine appendages is in this common species rather variable ; sometimes
they are rudimentary, at other times much stronger than in the good figure of Biitschli.)

Dimensions. — Shell diameter 0'08 to 0'09, horns and feet O'Ol to 0'03.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific ; also fossil in Barbados and Sicily.

1 Liriospyris = Lily-basket ; ^ii^iov, UWQI'S.
(ZOOL. CHALL. BXP. — PART XL. — 1886.) Er 132

1050 THE VOYAGE OF H.M.S. CHALLENGER.

3. Liriospyris heteropoda, n. sp.

Shell nut-shaped, nodose, with deep sagittal stricture and small circular pores ; two pairs of
larger pores on each side of the stricture. Basal plate with four larger central and eight smaller
peripheral pores. Apical horn conical, as long as the shell and twice as long as the two curved
frontal horns. Three primary feet twice as long as the shell and as the three secondary feet, which
are more highly inserted. All six feet slender curved, divergent.

Dimensions. — Shell 0'07 long, O'll broad; horn and secondary feet O'OS long, primary feet
015 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

4. Liriospyris turrita, Haeckel.

Ceratospyris turrita, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.
fig. 1.

Shell ovate, campanulate, smooth, with sharp sagittal stricture and irregular roundish pores ;
three to four pairs of larger pores on each side of the stricture. Basal plate with four large collar
pores. Three horns short and stout, conical, fenestrated at the base. Six feet slender, conical,
nearly vertical, of equal size, only one-third as long as the shell.

Dimensions. — Shell O'OS long, 0'06 broad; horns O'Ol long, feet 0'03 long.

Habitat. — Fossil in Barbados.

5. Liriospyris amphithecta, n. sp. (PL 95, fig. 7).

Shell nut-shaped, tuberculate, with distinct sagittal stricture and irregular roundish pores.
Basal plate with six larger and twelve smaller pores. Three horns conical, the apical as long as
the shell and twice as long as the curved frontal horns. Two pectoral feet cylindrical, very large,
curved, divergent, about three times as long as the shell and as the four other feet, which are
conical.

Dimensions. — Shell O'OS long, 0'12 broad ; apical horn O'OS, frontal horns 0'05 long ; length of
the two pectoral feet 0'2, of the four others 0'06.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 455. Cantharospyris,1 n. gen.
Definition. — :Z ygospyrida with six basal feet, without apical horn.

The genus Cantharospyris differs from the preceding two hexapodal genera
in the absence of horns on the coryphal face, and has therefore the same relation to
them that the hornless Tristylospyris bears to the one-horned Tripospyris and the three-
horned Triceraspyris.

1 Cantharospyris = Basket with six feet, like a beetle ; x«»0«jo?, <

REPORT ON THE RADIOLARIA, 1051

1. Cantharospyris cardbus, n. sp.

Shell nut-shaped, with deep sagittal stricture and irregular roundish pores. Basal plate with
six larger pores. Six feet of different sizes, cylindrical, curved ; three primary feet (one caudal and
two pectoral) about as long as the shell and twiee as long as the three secondary feet.

Dimensions. — Shell O08 long, 012 broad ; feet 0'05 to 0'09 long.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms ; Central Pacific, Station 268,
depth 2900 fathoms.

2. Cantharospyris ateuchus, Haeckel.

Ceratospyris ateuchus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xxi.
fig. 4.

Shell nut-shaped, tuberculate, with slight sagittal stricture and unequal circular pores. Basal
plate with six larger pores. The two pectoral feet very large and stout, four to six times as long
as the shell, widely divergent, curved. The four other feet much smaller and thinner, about as
long as the shell.

Dimensions. — Shell 0'06 long, 0'08 broad ; length of the two larger feet 0'2 to 0'3, of the four
smaller 0'05 to 0'07.

Habitat. — Fossil in Barbados.

3. Cantharospyris radicata, Haeckel.

Ceratospyris radicata, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 43;

Mikrogeol., 1854, Taf. xxii. fig. 37.

Haliomma radicatum, Ehrenberg, 1844, Monatsber, d. k. preuss. Akad. d. Wiss. Berlin, p. 83.
Petalospyris radicata, Haeckel, 1862, Monogr. d. RadioL, p. 295.
Petalospyris radicata, Stb'hr, 1880, Palaeontogr., vol. xxvi. p. 79, Taf. iii. fig. 11.

Shell nut-shaped, smooth, with slight sagittal stricture and irregular roundish pores ; two
larger pores on each side of the ring. Basal plate with six pores (?). Six feet of equal size
and similar form, conical, divergent, slightly curved, shorter than half the ring.

Dimensions. — Shell 0'05 long, 0'08 broad ; feet 0'02 long.

Habitat. — Fossil in Barbados and Sicily.

4. Cantharospyris platybursa, n. sp. (PI. 53, fig. 7).

Platybursa compressa, Haeckel, 1881, Prodromus, p. 429; Atlas, pi. 53, fig. 7.

Shell smooth, nearly discoidal circular, markedly compressed in the sagittal direction, with slight
basal stricture. Pores very numerous, irregular polygonal, with thin bars. Basal plate with four
very large pores. Six feet short, conical, nearly horizontally expanded. Two sagittal feet (caudal

1052 THE VOYAGE OF H.M.S. CHALLENGER.

and sternal) larger, about half as long as the shell (shortened in the figure). The two sternal feet
larger than the two small or rudimentary tergal feet.

Dimensions. — SheU 015 long, 013 broad ; feet 0'02 to 0'06 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Subfamily 5. PENTASPYEIDA, Haeckel, 1881, Prodromus, p. 442.

Definition. — Z ygospyrida pentapoda, with five descending basal feet, one odd
caudal foot, and two pairs of lateral feet (two anterior or pectoral, and two posterior or
tergal feet).

Genus 456. Clathrospyris,1 Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with five basal feet and one apical horn.

The genus Clathrospyris and the two following closely allied genera represent
together the small subfamily of Pentaspyrida, differing from the other Zygospyrida in
the possession of five descending feet on the basal face. Three of these are the primary
cortinar feet (of Cortiniscus, Plagoniscus, Tripospyris, &c.), whilst the two others are
secondary tergal feet. The Pentaspyrida may therefore be probably derived from the
Hexaspyrida by loss of the odd anterior or sternal foot.

1. Clathrospyris camelopardalis, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish. Basal
plate with six pores (?). Two pectoral feet very large, twice as long as the shell, cylindrical,
curved. Two tergal feet half as long and thick as the pectoral. Caudal foot and apical horn
straight, conical, half as long as the shell

Dimensions. — Shell 0*07 long, 0'09 broad ; horn and odd caudal foot 0'04 long ; pectoral feet
016, tergal 0'08 long.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

2. Clathrospyris pyramidalis, n. sp. (PI. 95, fig. 9).

Shell four-sided pyramidal, truncate, thorny, with slight sagittal stricture. Pores very large,
polygonal roundish. Two pairs of large pores on each side of the ring (at the frontal and the
occipital plate). Lateral pores more numerous. Basal plate with four large pores. The four
edges of the pyramid are prolonged into four short pyramidal divergent lateral feet (one-third as

1 CloAhrospyris = Latticed basket ;

REPORT ON THE RADIOLARIA. 1053

long as the shell). Caudal foot short. Horn at the apex of the truncate pyramid with two
lateral teeth.

Dimensions. — Shell 0'06 long, 0'08 broad ; horn and feet 0'02 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Clathrospyris fusiformis, n. sp.

Shell nearly cubical, smooth, with slight sagittal stricture. Pores roundish ; three pairs of
larger pores on each side of the ring. Basal plate with six large pores. Five feet of equal
length, slender, spindle-shaped, about as long as the shell, divergent. Apical horn conical, and half
as long as the feet.

Dimensions. — Shell 0'08 long, 0'09 broad ; horn 0'05 long, feet 01 long.

Habitat. — Fossil in Barbados.

Genus 457. Aegospyris,1 Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with five basal feet and three coryphal horns.

The genus Aegospyris differs from the preceding Clathrospyris, its ancestral form,
in the possession of three horns on the coryphal face (one odd apical, and two paired
frontal horns on each side), and therefore bears to the latter the same relation that
Triceraspyris does to Tripospyris, and Liriospyris to Hexaspyris.

1. Aegospyris aequispina, n. sp.

Shell nut-shaped, tuberculate, with slight sagittal stricture. 'Pores subregular circular. Basal
plate with four large collar pores. Three horns and five feet all of equal size and similar form,
slender conical, slightly curved, widely divergent, about as long as the shell.

Dimensions. — Shell 0'08 long, Oil broad ; horns and feet 0'08 long.

Habitat. — Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

2. Aegospyris octospina, n. sp.

Shell nearly cubical, smooth, with slight sagittal stricture. Pores subregular circular; two
pairs of larger pores on each side of the ring. Basal plate with four large pores. Two paired
horns and four paired feet of equal size and similar form, S-shaped curved, twice as long as the shell.
Odd horn and odd feet half as long, straight, conical.

Dimensions. — Shell 0'08 long, 0'09 broad ; six paired spines 0'2 long, two odd spines 01 long.

Habitat. — South Atlantic, Station 323, depth 1900 fathoms.

1 Aegospyris = Goat-basket ; a.<yotmv£t's.

1054 THE VOYAGE OF H.M.S. CHALLENGER.

3. Aegospyris longibarba, Haeckel.

Ceratospyris longibarba, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xxi.
figs. 1, 2.

Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores subregular circular. Basal
plate with four larger central, and eight smaller peripheral pores. Apical horn and caudal foot
short, straight, conical ; two frontal horns longer, curved ; four paired feet slender, curved, twice as
long as the shell.

Dimensions. — Shell 0'06 long, O08 broad ; paired horns 0-03 long, paired feet O'l long.

Habitat. — Fossil in Barbados.

4. Aegospyris aegoceras, n. sp. (PL 95, fig. 10).

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish. Basal
plate with three large pores. Apical horn and caudal foot short, straight, spindle-shaped ; two
frontal horns as long as the shell, strongly curved ; four paired feet also curved, at the distal end
forked, divergent ; the tergal thinner and as long as the shell, the pectoral thicker and twice as
long.

Dimensions. — Shell O07 long, 0'09 broad ; pectoral feet O'l long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

5. Aegospyris caprina, n. sp. (PL 86, fig. 8).

Shell nut-shaped, papillate, with sharp sagittal stricture. Pores irregular roundish, two pairs of
larger pores on each side of the ring. Basal plate with six large pores. Eight spines all straight,
subvertical and nearly parallel, cylindro-conical. Two frontal horns and two tergal feet about as
long as the shell ; odd horn shorter ; odd foot longer. Two pectoral feet twice as long as the
shell, club-shaped, with a spinulate knob at the distal end.

Dimensions. — Shell 0'06 long, 0'09 broad ; pectoral feet O'll long.

Habitat. — Central Pacific, Station 271, surface.

Genus 458. Pentaspyris,1 Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with five basal feet, without apical horn.

The genus Pentaspyris differs from the two preceding genera in the absence of any
coryphal horn, and represents therefore the pentapodal form among the hornless
Zygospyrida.

1. Pentaspyris pentacantha, n. sp. (PL 95, fig. 11).

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish, two pairs
of larger pores on each side of the ring. Basal plate with four larger pores. All five feet cylin-

1 Pentaspyris = Basket with five feet ; •riurti,

REPORT ON THE RADIOLARIA. 1055

drical, S-shaped curved, strongly divergent, with few short branches, the two pectoral feet twice as
long as the shell and the two tergal feet ; odd caudal foot shorter.

Dimensions. — Shell 0'08 long, 013 broad ; pectoral feet 0'2 long, tergal feet 01, caudal foot
0-06.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Pentaspyris isacantha, n. sp.

Shell subspherical, smooth, with slight sagittal stricture. Pores small, regular circular. Basal
plate with six large pores (?). All five feet equal, cylindrical, C-shaped curved, slightly divergent,
about as long as the shell.

Dimensions. — Shell 0'08 long, 0'09 broad ; feet 0'07 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Subfamily 6. THEROSPYKIDA, Haeckel, 1881, Prodromus, p. 442.

Definition. — Z ygospyrida tetrapoda with two pairs of descending basal feet,
one pair corresponding to the anterior or pectoral, the other pair to the posterior or
tergal feet of the Hexaspyrida.

Genus 459. Zygospyris,1 Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with two pairs of lateral feet and an apical horn.

The genus Zygospyris and the following three genera represent together the peculiar
subfamily of Therospyrida. These always possess four basal feet, like the Tetraspyrida ;
but whilst in the latter group two feet are sagittal, and two lateral, in the Therospyrida
there are no sagittal feet at all, but the four feet are opposed in two lateral pairs ;
the anterior pair corresponds to the pectoral, the posterior to the tergal feet of the
Hexaspyrida and Pentaspyrida ; from these latter the Therospyrida have been derived
by loss of the sagittal feet.

1. Zygospyris quadrupes, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular roundish, on each
side of the ring two pairs of larger pores. Apical horn conical, straight. Four feet equal, straight,
divergent, conical, about as long as the shell and the horn.

Dimensions. — Shell 0'08 long, Oil broad; horn and feet 01 long.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

1 Zygospyris = Bilocukr basket, with paired halves ; £vy«,

1056 THE VOYAGE OF H.M.S. CHALLENGER.

2. Zygospyris equus, n. sp. (PL 83, fig. 16).

Shell subspherical, rough, with slight sagittal stricture. Pores small and numerous, subregular
circular ; no larger annular pores. Apical horn cylindrical, half as long as the shell. Two pectoral
feet somewhat smaller than the two tergal feet, about as long as the shell, slightly divergent,
cylindrical. The distal ends of the feet and of the horn form an ovate, dimpled and spinulate cone.

Dimensions. — Shell 0'06 long, 0'09 broad ; horn 0'04 long, feet 0'06 long.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 460. Elaphospyris? Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with two pairs of lateral feet and three coryphal horns.

The genus Elaphospyris differs from the preceding Zygospyris, its ancestral form, in
the possession of three coryphal horns (one odd apical and two paired frontal horns), and
therefore bears to it the same relation that Triceraspyris does to Tripospyris among
the Tripospyrida.

•

Subgenus 1. Giraffospyris, Haeckel, 1881, Prodromus, p. 442.
Definition.— Feet simple, not branched nor forked.

1. Elaphospyris heptaceros, Haeckel.

Ceratospyris heptaceros, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xx.

fig. 2.
Giraffospyris heptaceros, Haeckel, 1881, Prodromus, p. 442.

Shell nut-shaped, tuberculate, with slight sagittal stricture and subregular circular pores.
Basal plate with four large pores. Apical horn small conical, shorter than the two curved lateral
horns, which are as long as the shell. Caudal and sternal feet small, conical, straight. Two
pectoral feet slender, divergent, S-shaped, about as long as the shell.

Dimensions. — Shell OD5 long, 0'07 broad ; horns and feet 0'02 to O'OOS long.

Habitat. — Fossil in Barbados.

2. Elaphospyris capricornis, n. sp.

Shell nut-shaped, spiny, with slight sagittal stricture and numerous small circular pores.
Basal plate with four large pores. Three horns slender, simple, about as long as the shell, the
middle one straight, the two lateral curved. Four feet of nearly equal size, slender, curved, divergent,
simple, twice as long as the shell and the horns.

Dimensions.— Shell 0'07 long, 009 broad ; horns O'OS long, feet 015 long.

Habitat.— Central Pacific, Station 274, depth 2750 fathoms.

1 Elaplwspyris = Deer-basket ;

REPORT ON THE RADIOLARIA. 1057

Subgenus 2. Corythospyris, Haeckel, 1881, Prodromus, p. 443.
Definition. — Feet branched or forked.

3. Elaphospyris damaecornis, n. sp. (PI. 84, fig. 10).

Shell flat and broad, nearly triangular, with slight sagittal stricture and irregular roundish
pores ; two very large pores on the frontal and on the occipital face, opposite on both edges of
the broad sagittal ring. Basal plate with four large central and several smaller lateral pores.
Three horns about half as long as the shell, with two to six irregular branches. Four feet
of equal size, about as long as the shell, divergent, forked, with four to six irregular terminal
branches. (The shell in fig. 10 is seen from the apical side.)

Dimensions. — Shell 0-09 long, 013 broad ; horns 0'05 long, feet 01 long.

Habitat. — Indian Ocean, Cocos Islands, Eabbe, surface.

4. Elaphospyris cervicornis, n. sp. (PI. 86, fig. 13).

Shell polyhedral, spiny, with deep sagittal stricture and a small number of large roundish
pores ; two pairs of large pores on each side of the ring. Basal plate with four pores. Three
large horns as long as the shell arise from the apex between smaller conical spines ; the middle odd
horn simple, the two lateral each with a pair of branches. Two pectoral feet very large, divergent,
with broad and irregular distal ramification, twice as long as the shell and as the two tergal feet,
which are less branched. (Fig. 13 exhibits the shell from the dorsal side.)

Dimensions. — Shell 0'09 long, Oil broad ; horns and smaller feet 0'07 to 0'09 long ; pectoral
feet 016 long.

Habitat.— Central Pacific, Station 271, depth 2425 fathoms.

5. Elaphospyris alcicornis, n. sp. (PI. 86, fig. 12).

Shell nut-shaped, spiny, with sharp sagittal stricture and large roundish pentagonally framed
pores ; three pairs of larger pores on each side of the ring. Basal plate with four larger and four
alternate smaller pores. There arise from the apex, between smaller spines, three large, divergent,
pyramidal horns, which are nearly as long as the shell, and connected by an arched frontal bridge.
Two pectoral feet very large, divergent, prismatic, longer than the shell, and at the distal end with
a bunch of thick spines. Two tergal feet half as long and thick, simple (in the figure hidden
behind the large pectoral feet).

Dimensions. — Shell 0'09 long, Oil broad ; horns and smaller feet 0'06 long, pectoral feet
012 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

(ZOOL. CHALL. EXP. PART XL. 1886.) Rt 133

1058 THE VOYAGE OP H.M.S. CHALLENGES.

Genus 461. Taurospyris ? Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with two pairs of lateral feet and one pairof lateral horns.

The genus Taurospyris bears only two frontal horns in the coryphal face of the shell,
and may therefore be derived from the preceding closely allied Elaphospyris by reduction
and loss of the middle or apical horn.

1. Taurospyris cervina, n. sp. (PL 95, fig. 12).

Shell nut-shaped, thorny, with deep sagittal stricture and irregular roundish pores ; three pairs
of larger pores on each side of the ring. Basal plate with four large pores. Two horns cylindrical,
curved, widely divergent, about as long as the shell, branched. Tour feet of nearly equal length,
also cylindrical and curved, divergent, somewhat longer than the shell, in the distal half branched
like a deer's antler.

Dimensions. — Shell 0'07 long, O'll broad ; horns 0'03 long, feet 0'06 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms ; also fossil in Barbados.

2. Taurospyris bovina, n. sp.

Shell subspherical, smooth, with slight sagittal stricture and small circular pores. Basal plate
with six larger pores. Two horns conical, curved, divergent, about as long as the shell. Two
pectoral feet very large, twice as long as the shell and as the two thinner tergal feet ; all four feet
curved, cylindrical, divergent, pointed at the distal end.

Dimensions. — Shell 0'08 long, 0'09 broad ; horns and posterior feet O'l, anterior feet 0'2 long.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 462. TJierospyris? Haeckel, 1881, Prodromus, p. 442.
Definition. — Z ygospyrida with two pairs of lateral feet, without apical horn.

The genus Therospyris has two pairs of lateral feet corresponding to those of the pre-
ceding three genera, but differs from them in the complete absence of horns on the
coryphal face of the shell.

1. Therospyris canis, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores irregular, roundish. Basal
plate with four longer pores. Surface covered with roundish tubercles. Four feet equal, divergent,
about as long as the shell, thickened at the distal end, club-shaped, not forked.

Dimensions. — Shell 0'07 long, Oil broad ; feet 0'09 long.

Habitat. — Fossil in Barbados.

1 Taurospyris= Bull-basket ; ra,vi>os, avv^lf.

2 Tlierospyris= Basket with, four feet, like a beast ; 6*1%,

REPORT ON THE RADIOLARIA. 1059

2. Therospyris felis, n. sp. (PI. 89, fig. 6).

Shell nut-shaped, mammillate, with sharp sagittal stricture. Pores large, irregularly roundish
or polygonal, of somewhat different size. Basal plate with four large pores. Surface covered with
hemispherical pointed mammillae. Four feet equal, divergent, half as long as the shell, at the distal
end forked, with few small branches.

Dimensions. — Shell 01 long, 015 broad; feet 0'05 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Therospyris leo, n. sp. (PL 89, fig. 5).

Shell nearly cubical, papillate, with slight sagittal stricture. Pores irregular, roundish; on each
side of the ring three pairs of larger pores (the undermost the largest). Basal plate with two large
pores. Surface covered with conical papillae. Four feet equal, divergent, about as long as the
shell, with an external spur in the middle, and irregularly branched spines at the distal end.

Dimensions. — Shell 0'08 long, 012 broad ; feet 0'09 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subfamily 7. POLYSPYRIDA, Haeckel, 1881, Prodromus, p. 442.

Definition. — Zy go spy rid a polypoda, with numerous descending basal feet (at
least seven to nine, usually twelve to sixteen or more).

Genus 463. Petalospyris,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — Z ygospyrida with numerous (seven to twelve or more) basal feet
and one apical horn.

The genus Petalospyris and the following three genera form together the peculiar
subfamily of Polyspyrida, differing from the other Zygospyrida in the multiplication of
the radial feet, which descend from the basal face of the shell ; they may therefore be
also called " Zygospyrida multiradiata," and bear the closest relationship to the Archi-
phaenida (or the " Monocyrtida multiradiata "). They differ, however, from the latter
in the presence of the distinct sagittal stricture, characteristic of all S p y r o i d e a.
The number of the basal feet, which form a coronet around the margin of the basal
plate, is commonly between twelve and sixteen, but often more. Their form is usually
flat, lamellar, but often also more or less cylindrical or conical.

1 Petalospyris = Leaf-basket ; •

1060 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 1. Petalospyrantha, Haeckel.

Definition. — Basal plate with two large collar pores only, separated by the base of
the primary ring.

1. Petolospyris foveolata, Ehrenberg.

Petalospyris foveolata, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 14; AbhandL d. k. Akad. d.
Wiss. Berlin, 1875, p. 80, Taf. xxii. fig. 10.

Shell campanulate, smooth, with distinct sagittal stricture and subregular circular pores. Basal
plate with two large collar pores only. Apical horn and the eight feet slender, conical, slightly
curved, about as long as the shell ; feet somewhat divergent (often seven or nine instead of eight).

Dimensions. — Shell diameter 0'04 to 0'05 ; length of the horn and the feet 0'04 to 0'05.

Habitat. — Fossil in Barbados.

2. Petalospyris floscula, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture and subregular circular pores. Basal
plate with two large triangular pores only. Apical horn slender, conical, twice as long as the shell.
Twelve to sixteen feet flattened, leaf-shaped, broad, slightly divergent, as long as the shell, with
truncate distal end.

Dimensions. — Shell 0'06 long, 0'09 broad ; horn 012 long, feet 0'05 to 0'07 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 2. Petalospyrella, Haeckel.

Definition. — Basal plate with three large collar pores (two paired posterior cardinal,
and an odd anterior sternal pore).

3. Petalospyris triomma, n. sp. (PI. 87, fig. 14).

Shell nut-shaped, tuberculate, with sharp sagittal stricture and irregular roundish pores. Basal
plate with three large pores and three alternate smaller. Apical horn stout, conical, half as long as
the shell. Twelve to fifteen feet, divergent, curved, pointed, as long as the horn.

Dimensions. — Shell 0'06 long, OD8 broad ; horn and feet 0'03 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Petalospyris platyacantha, Ehrenberg.

Petalospyris platyacantha, Ehrenberg, AbhandL d. k. Akad. d. Wiss. Berlin, 1875, p. 80,
Taf. xxii. fig. 8.

Shell campanulate, smooth, with slight sagittal stricture and small irregular roundish pores.
Basal plate with three large pores (?). Apical horn very strong, three-sided pyramidal, twice as

REPORT ON THE RADIOLARIA. 1061

long as the shell (its edge is described by Ehrenberg as a " canaliculus.") Feet ten to twelve, flat,
triangular, vertical, about as long as the shell

Dimensions. — Shell 0-04 long, 0'05 broad ; horn 0'07 long, feet 0'03 long.

Habitat. — Fossil in Barbados.

5. Petalospyris corona, Stohr.

Petalospyris corona, Stohr, 1880, Palseontogr., vol. xxvi. p. 98, Taf. iii. fig. 13.

Shell nut-shaped, smooth, with slight sagittal stricture and very numerous small circular pores ;
on each side of the stricture three larger annular pores (the undermost the largest). Basal plate
with three large pores only. Apical horn very small, conical. Feet twelve to eighteen, short
conical, nearly vertical, shorter than the half shell (in my specimen from Caltanisetta much stouter
than in that of Stohr).

Dimensions. — Shell 0'07 long, 0'09 broad ; horn and feet O'Ol to 0'03 long.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).

Subgenus 3. Petalospyrissa, Haeckel.

Definition. — Basal plate with four collar pores (two larger posterior cardinal and
two smaller anterior jugular pores).

6. Petalospyris octopus, n. sp. (PI. 87, fig 11).

Shell nut-shaped, tuberculate, with sharp sagittal stricture and irregular, roundish pores. Basal
plate with four larger pores. Horn slender, conical, half as long as the shell. Feet eight, very
slender, about three times as long as the shell, subvertical, with outer convex edge and convergent
ends.

Dimensions. — Shell 0'06 long, 0'09 broad ; horn O03 long, feet 02 long.

Habitat. — Tropical Atlantic, Station 342, depth 1445 fathoms.

7. Petalospyris eupetala, Ehrenberg.

Petalospyris eupetala, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii.

fig. 4.

Shell nut-shaped, tuberculate, with slight sagittal stricture and scattered small circular pores.
Basal plate with four large collar pores (sometimes surrounded by several small peripheral pores).
Apical horn slender, conical, as long as the shell. Feet sixteen to twenty, laminated and truncate,
of the same length, nearly vertical and parallel.

Dimensions. — Shell 0'06 long, 0-08 broad; horn and feet O05 to 0'07 long.

Habitat. — Fossil in Barbados.

1062 THE VOYAGE OF H.M.S. CHALLENGER.

8. Petalospyris anthemis, n. sp.

Shell nut-shaped, spinulate, with deep sagittal stricture and irregular, roundish pores. Basal
plate with four large pores of equal size. Apical horn conical, twice as long as the shell. Feet
twenty to thirty, laminated and truncate, as long as the shell, divergent.

Dimensions. — Shell 0'05 long, 0'08 broad; horn O'l long, feet 0'6 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

9. Petalospyris tessaromma, n. sp.

Shell subspherical, with slight sagittal stricture and few small pores ; on each side of the
stricture four larger, square, annular pores. Basal plate with four large collar pores (two larger
cardinal and two smaller jugular pores). Horn and feet conical, about half as long as the shell.
Feet twenty to twenty-five, slightly curved, convergent.

Dimensions. — Shell diameter 0'08 ; horn and feet 0'04

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

Subgenus 4. Petalospyromma, Haeckel.

Definition. — Basal plate with numerous (six or more) collar pores, commonly three
or four larger central, and six to twelve smaller peripheral pores.

10. Petalospyris novena, n. sp. (PI 83, fig. 12).

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, roundish pores. Basal
plate with nine pores (three large primary and three alternate pairs of small secondary pores).
Nine long corresponding feet, twice to four times as long as the shell (three very thick primary,
and three alternate pairs of thin secondary feet). All feet cylindrical, curved, widely divergent.
Horn conical.

Dimensions. — Shell 0'06 long, 0'08 broad ; horn and feet O'lo to 0'25.

Habitat.— Indian Ocean (Cocos Islands), Rabbe, surface.

11. Petalospyris argiscus, Ehrenberg.

Petalospyris argiscus, Ehrenberg, 1875, Abhandl. d. k. Akad. Wiss. Berlin, p. 80, Taf. xxii.

figs. 1, 2.
Petalospyris argiscus, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi p. 539, Taf. xxxii.

fig. 17, a, b.

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, roundish pores. Basal
plate with nine pores (three larger central and three alternate pairs of smaller peripheral pores).

REPORT ON THE RADIOLARIA. 1063

Apical horn slender, spindle-shaped, about as long as the shell. Twenty to twenty-five feet, of the
same length, broad, lamellar and truncate, nearly vertical, slightly divergent.

Dimensions. — Shell 0'06 long, 01 hroad ; horn and feet O'Oo to 0'07 long.

Habitat. — Fossil in Barbados.

12. Petalospyris papillata, n. sp.

Shell nearly cubical, papillate, without external sagittal stricture, with small, irregular, roundish
pores. Basal plate with six pores (three larger and three alternate smaller). Apical horn conical,
half as long as the shell. Feet twenty to thirty, one-half to one-third as long, conical, divergent.

Dimensions. — Shell diameter 0'09 ; horn 0'04 long, feet 0'03 to O05 long.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

13. Petalospyris dictyocubus, n. sp. (PI. 86, fig. 6).

Shell nearly cubical, smooth, without external stricture, but with a complete, parietal, square,
sagittal ring. On each side of the ring four pairs of larger pores, whilst the lateral pores are
smaller and more numerous. Basal plate also with four pairs of larger pores and smaller lateral
pores. Apical horn and basal feet short, pyramidal, scarcely one-fourth as long as the shell. The
three primary feet are larger than the six to nine secondary feet.

Dimensions. — Shell diameter 0'08 ; horn and feet 0'02 long.

Habitat. — Central Pacific, Station 274, surface.

14. Petalospyris bellidiastrum, n. sp.

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, roundish pores. Basal
plate with twelve pores (four central larger and eight peripheral smaller pores). Apical horn
slender, conical, about as long as the shell (sometimes ramified at the distal end). Feet sixteen to
twenty, broadly lamellar, truncate, divergent, about as long as the shell

Dimensions. — Shell 0'08 long, 01 broad; horn and feet O'OV to 0'09 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; also fossil in Barbados.

15. Petalospyris dinoceras, n. sp. (PL 87, fig. 12).

Shell nut-shaped, mammillate, without external stricture, but with complete external sagittal
ring. Pores subregular, circular. Basal plate with four large central pores, surrounded by a circle
of twelve to twenty small peripheral pores. Apical horn very large, spindle-shaped, one and a half
times as long as the shell. Feet twenty-five to thirty, broadly lamellar, truncate, divergent, about
as long as the shell.

Dimensions. — Shell Oil long, 013 broad ; horn 015 long, feet 0'09 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

1064 THE VOYAGE OF H.M.S. CHALLENGER.

16. Petalospyris furcata, n. sp.

Shell nut-shaped, smooth, with sharp sagittal stricture. Pores numerous, small, and circular ;
no larger annular pores. Basal plate with four larger and four alternate pairs of smaller pores.
Horn conical, about as long as the shell Feet fifteen to twenty, broadly lamellar, about twice as
long as the shell, in the distal half forked.

Dimensions. — Shell 0'04 long, O06 broad ; horn 0'05 long, feet 01 long.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

17. Petalospyris lobata, n. sp. (PL 87, fig. 13).

Shell subspherical, smooth, with slight sagittal stricture. Pores small, roundish ; on each side
of the ring two pairs of larger annular pores. Basal plate with four pores. Horn stout, three-
sided prismatic, half as long as the shell. Feet twelve to sixteen, lamellar, lobate (the most part
with three lobes), nearly vertical, about as long as the shell.

Dimensions. — Shell diameter 0'05 ; horn 0'03, feet 0'05 long.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

Genus 464. Anthospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — Z ygospyrida with numerous (seven to nine or more) basal feet and
three coryphal horns.

The genus Anthospyris differs from the preceding Petalospyris, its ancestral form,
in the possession of three horns on the coryphal face (one odd middle apical horn and
two paired frontal horns, one on each side). The former therefore bears to the
latter the same relation that Triceraspyris does to Tripospyris and Liriospyris to
Hexaspyris.

1. Anthospyris mammillata, n. sp. (PI. 87, fig. 16).

Shell nut-shaped, mamniillate, with deep sagittal stricture and irregular, polygonal pores. Basal
plate with two large ovate pores (?). The pediculate apical horn and the two frontal horns stout
and short, conical, twice to three times as large as the conical papillae of the surface. Feet twelve to
fifteen, lanceolate lamellar, pointed, divergent, about as long as the shell.

Dimensions. — Shell 0'05 long, 0'08 broad ; horns 0'03, feet 0'04 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

1 Anthospyris= Flower-basket ; oMo?, oirvf>tg.

REPORT ON THE RADIOLARIA. 1065

2. Anthospyris spathulata, n. sp. (PL 87, fig. 15).

Shell subspherical, thorny, with slight sagittal stricture and irregular, roundish pores. Basal
plate with three large pores. The three horns spindle-shaped, half as long as the ten to twelve
thin feet, which are pediculate, shovel-shaped, a little divergent, and shorter than the shell

Dimensions. — Shell 005 diameter ; horn 0'02 long, feet 0'04 long.

HaUtat. — North Pacific, Station 250, depth 3050 fathoms.

3. Anthospyris didboliscus, HaeckeL

Petalospyris diaboliscus, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 12; AbhandL d. k. Akad.
d. Wiss. Berlin, 1875, p. 80, Taf. xxii. fig. 3.

Shell nut-shaped, smooth, with slight sagittal stricture and small circular pores. Basal plate
with four large pores. Apical horn straight conical, frontal horns curved laterally. Feet nine to
twelve, of about the same length as the horns and the shell, broad lamelliform, truncate, nearly
vertical, slightly curved.

Dimensions. — Shell 0'04 long, 0'07 broad ; horns and feet 0'05 to 0'07 long.

Habitat. — Fossil in Barbados.

4. Anthospyris arachnoides, Haeckel.

Petalospyris arachnoides, Haeckel, 1862, Monogr. d. RadioL, p. 294, Taf. xLL fig. 7.

Shell nut-shaped, tuberculate, with slight sagittal stricture and irregular, polygonal pores. Basal
plate with four large pores (?). Apical horn straight, conical, longer than the two curved lateral
horns. Feet ten, slender, S-shaped, widely divergent, about as long as the shell is broad.

Dimensions. — Shell 0'05 long, 0'08 broad ; horns 0'03 to 0'05 long, feet 0'08 long.

Habitat. — Mediterranean (Messina), Atlantic, Station 354, surface.

5. Anthospyris aculeata, n. sp. (PI. 86, fig. 5).

Shell campanulate, spiny, with deep sagittal stricture and irregular, roundish pores. On each
side of the stricture three pairs of larger annular pores. Basal plate with two large square pores.
The three horns of the same size as, and similar form to, the ten to fifteen feet, slender pyramidal,
straight, divergent, about half as long as the shell. (This species is very variable and closely allied
to Ceratospyris.)

Dimensions. — Shell diameter 0'08 to 0'12 ; horns and feet 0'04 to 0'06 long.

Habitat. — Central Pacific, Stations 266 to 274, surface.

6. Anthospyris doronicum, n. sp. (PL 87, fig. 18).

Shell nut-shaped, spiny, with a deep sagittal stricture and small circular pores. On each side
of the stricture two pairs of very large square annular pores. Basal plate with four larger collar

(ZOOL. CHALL. EXP. — PAET XL. — 1886.) Rr 134

1066 THE VOYAGE OF H.M.S. CHALLENGER.

pores and a corona of numerous small peripheral pores. Three horns spindle-shaped, divergent'
about half as long as the shell. Feet twenty-five to thirty, broad, lamellar, lanceolate, pointed
divergent, nearly as long as the shell.

Dimensions. — Shell 01 long, 013 broad ; horns 0'06, feet 0'09 long.

Habitat. — South Pacific, Station 296, depth 1825 fathoms.

7. Anthospyris tragopogon, n. sp. (PI. 87, fig. 17).

Shell nut-shaped, tuberculate, with distinct sagittal stricture and small regular circular pores.
Basal plate with numerous small pores. Apical horn very large, spindle-shaped, twice as long as
the shell ; frontal horns small, scarcely one-fourth as long, curved laterally. Feet twenty-five to
thirty, three to four times as long as the shell, lamellar, lanceolate, pointed, parallel, vertical

Dimensions. — Shell 0-08 long, Oil broad; apical horn 016, feet 0'2 long.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

Genus 465. Ceratospyris,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 54.

Definition. — Zygospyrida with numerous (seven to twelve or more) basal feet
and numerous coryphal horns.

The genus Ceratospyris differs from all the other Zygospyrida in the possession of
numerous large spines on the surface of the shell, which usually exhibits only a small
number of large pores or meshes. The lower spines which cover the inferior or basal face
of the shell (usually nine to twelve or more) may be compared to the descending " basal
feet " of the other Zygospyrida ; the upper spines, however, which cover the superior or
coryphal face (usually six to nine, rarely more), may be regarded as " coryphal horns."
In many species of this genus the lattice-work of the shell is of a peculiar loose kind,
with few large meshes, resembling the wicker-work of the Plectanida.

Subgenus 1. Lophospyris, Haeckel, 1881, Prodromus, p. 443.

Definition. — Spines simple, not branched. Meshes of the shell usually polygonal, or
roundish with polygonal frames. Bars of the network prismatic.

1. Ceratospyris polygona, n. sp. (PI. 86, fig. 1).

Shell polyhedral, with deep sagittal stricture, studded with twenty-four to thirty long simple
straight slender pyramidal spines, which are as long as the shell or longer. All pores large,
polygonal. On the frontal and the occipital face two pairs of very large pores only, the superior

1 Ceratospyris — Horned basket ; ai^t; ,

REPORT ON THE RADIOLARIA. 1067

pentagonal, larger than the inferior tetragonal. Basal plate with two triangular pores. Bars of
the loose framework three-sided prismatic, thin.

Dimensions. — Shell 0'08 long, 012 broad ; spines 0'06 to 012 long.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, surface.

2. Ceratospyris pentagona, Ehrenberg.

Ceratospyris pentagona, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wise. Berlin, p. 287, Taf. x.
fig. 15.

Shell polyhedral, with slight sagittal stricture, studded with twenty-four to thirty small simple
conical spines, which are shorter than one-fourth of the shell. Most pores pentagonal On the
frontal and the occipital face two pairs of large pores only, the superior smaller than the inferior.
Basal plate with four quadrangular pores. Bars of the network prismatic, thin.

Dimensions. — Shell 0'07 long, Oil broad ; spines O'Ol to 0'02 long.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, surface.

3. Ceratospyris allmersii, n. sp. (PL 86, fig. 3).

Shell polyhedral, with slight sagittal stricture, studded with thirty to forty prismatic spines
which are not longer than half the shell. Most pores pentagonal. On the frontal face two, on
the occipital three pairs of larger pores ; the inferior the largest. Basal plate with two rhomboidal
pores (?). Bars of the network three-sided prismatic, thin. Dedicated to my dear friend, the
excellent poet and naturalist, Hermann Allmers, of Eechtenfleth.

Dimensions. — Shell 0'08 long, 012 broad ; spines O'Ol to 0'03.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

4. Ceratospyris mulderi, n. sp. (PI. 86, fig. 4).

Shell polyhedral, with deep sagittal stricture, studded with fifty to seventy prismatic spines ;
two inferior (pectoral) spines about as long as the shell, the others much shorter. Pores polygonal.
On the frontal and the occipital face one pair of very large pores. Basal plate with two distinctly
hexagonal pores. Bars of the loose network prismatic. Dedicated to my dear friend, the excellent
author and painter, Ludwig Mulder, of the Hague.

Dimensions. — Shell 0'07 long, 012 broad ; spines O'Ol to 0'08.

Habitat. — Indian Ocean, Sunda Straits (Eabbe), surface.

5. Ceratospyris strasburgeri, n. sp. (PI. 86, fig. 2).

Shell polyhedral, with slight sagittal stricture, studded with thirty to forty prismatic spines,
which are about half as long as the shell (two or four inferior are longer). Pores roundish, with
polygonal frames. On the frontal and occipital face two pairs of larger pores (the superior

1068 THE VOYAGE OF H.M.S. CHALLENGER.

smaller). Basal plate with two large pentagonal pores. Bars of the network prismatic. Dedicated
to my dear friend, the celebrated botanist, Professor Eduard Strasburger, of Bonn.

Dimensions. — Shell 0'07 long, O'l broad; spines 0'02 to 0'04.

Habitat. — Western Tropical Pacific, Station 225, depth 4475.

6. Ceratospyris mulleri, Stohr.

Ceratospyris mulleri, Stohr, 1880, Palaeontogr., voL xxvi. Taf. iii. fig. 15.

Shell polyhedral, with slight collar stricture, studded with forty to fifty pyramidal spines, shorter
than half the shell Pores circular, with pentagonal frames of the same breadth, all nearly of equal size.
(Basal plate with four pores ?) Bars of the network prismatic. Dedicated to Johannes Miiller.

Dimensions. — Shell 0'08 long, 01 broad ; spines O'Ol to 0'03.

Habitat. — Fossil in Tertiary rocks of Sicily, Grotte (Stohr).

7. Ceratospyris krausei, n. sp. (PL 86, fig. 10).

Shell nut-shaped, with deep sagittal stricture, studded with forty to fifty strong conical
spines ; six basal spines as long as the shell and two to three times as long as the others. Pores
roundish polygonal, twice to three times as broad as the bars ; two pairs of larger pores on each
side of the ring. (Basal plate with four large pores ?) Bars of the network rounded, thick.
Dedicated to my dear friend, the excellent author, Ernst Krause (Carus Sterne), of Berlin.

Dimensions. — Shell 0'06 long, 0'09 broad ; spines 0'03 to 0'08.

Habitat. — Western Tropical Pacific (Philippine Sea), Station 206, depth 2100 fathoms.

8. Ceratospyris preyeri, n. sp. (PL 86, fig. 9).

Shell nut-shaped, with slight sagittal stricture, studded with ten to twelve longer club-shaped
spines (about as long as the shell) and numerous smaller conical spines. Pores irregular, roundish,
numerous ; two pairs of larger pores on each side of the ring. Basal plate with four large pores.
Bars of the network rounded. Dedicated to my honoured friend and colleague, the celebrated
investigator of psychical ontogeny, Professor William Preyer, of Jena.

Dimensions. — Shell 0'07 long, 0'09 broad ; spines 0'02 to 008 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

9. Ceratospyris echinus, Ehrenberg.

Ceratospyris echinus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66,
Taf. xx. fig. 12.

Shell subspherical, with slight sagittal stricture, studded with numerous conical curved spines ;
six basal and one apical spine are larger than the others, about as long as the shell. Pores numerous,
small, circular. Basal plate with numerous pores. Bars of the network roundish.

Dimensions. — Shell 0'05 long, 0'06 broad ; spines 0'02 to 0'05 long.

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA; 1069

Subgenus 2. Cladospyris, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — Spines forked or branched. Meshes roundish or polygonal.

10. Ceratospyris ramosa, Ehrenberg.

Ceratopyris ramosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 66, Taf. xx. fig. 7.
Cladospyris ramosa, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 54.

Shell nut-shaped, with slight sagittal stricture, studded with numerous conical, irregularly
branched spines. The largest about as long as the shell. Pores irregular, roundish ; on each side
of the ring two pairs of larger pores. Basal plate with four pores. Bars of the network roundish.

Dimensions. — Shell 0'06 long, 0'08 broad ; spines 0'02 to 0'08 long.

Habitat. — Fossil in Barbados.

11. Ceratospyris carnerii, n. sp. (PI. 86, fig. 11).

Shell nut-shaped, with sharp sagittal stricture, studded with numerous pyramidal spines ; two
basal spines are larger, as long as the shell, and irregularly branched. Pores polygonal ; on each
side of the ring three pairs of larger pores. Basal plate with four large pores. Dedicated
to my dear friend, the excellent monistic philosopher, B. von Carneri.

Dimensions. — Shell 0'09 long, 012 broad ; spines O02 to 0-08 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

12. Ceratospyris calorrhiza, n. sp. (PI. 87, fig. 19).

Shell nut-shaped, with deep sagittal stricture, studded with numerous conical strong spines,
about one-fourth as long as the shell. Basal spines irregularly branched, with root-like ends.
Pores irregular, roundish, some larger pores on each side of the ring. Basal plate with four larger
pores. Bars of the network roundish.

Dimensions. — Shell O'l long, 0'14 broad ; spines 0'02 to 0-04 long.

Habitat. — Central Pacific, Station 271, surface.

Genus 466. Gorgospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — Z ygospyrida with numerous (seven to twelve or more) basal feet,
without coryphal horns.

The genus Gorgospyris agrees with the three preceding genera in the possession of
numerous basal feet, but differs from them in the complete absence of any horns on the
coryphal face. It represents therefore the " hornless polypedal Zygospyrida,' and may

1 Gorgospyris = Medusiform basket ; yo;-/u,

1070 THE VOYAGE OF H.M.S. CHALLENGER.

be derived from Petalospyris by loss of the original apical horn. The feet are commonly
numerous, and often form a circle around the margin of the basal plate, similar to the
circle of tentacles in many Medusae (Gorgon).

Subgenus 1. Gorgospyrium, Haeckel.
Definition. — Feet simple, not branched.

1. Gorgospyris medusa, n. sp. (PI. 87, fig. !)•

Shell hemispherical, papillate, with slight sagittal stricture and subregular circular pores.
Basal plate with three large collar pores (by mistake not correctly represented in the figure). Ten
to twelve slender feet, twice as long as the shell, strongly curved and divergent, of equal length.

Dimensions. — Shell O06 long, 0'08 broad ; feet O'l long.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

2. Gorgospyris medusetta, n. sp. (PL 87, fig. 2).

Shell nut-shaped, smooth, with deep sagittal stricture and irregular, roundish pores. Basal
plate with three large collar pores, alternating with three pairs of smaller pores. Sixteen to twenty
slender feet, about as long as the shell, slightly curved and divergent, of nearly equal length.

Dimensions. — Shell 0'05 long, 0-08 broad; feet 0'05 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Gorgospyris ehrenbergii, Haeckel.

Petalospyris pentas, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii.
fig. 11.

Shell nut-shaped, smooth, with slight sagittal stricture and unequal circular pores. Basal
plate with three large central pores, alternating with three pairs of smaller pores, and with a peri-
pheral circle of smaller pores. Twenty-four to thirty short truncated feet, shorter than half the
shell.

Dimensions. — Shell 0'05 long, 0'07 broad ; feet 0'02 long.

Habitat. — Fossil in Barbados.

4. Gorgospyris polypus, n. sp. (PI. 87, fig. 3).

Shell hemispherical, papillate, with slight sagittal stricture and subregular circular pores.
Basal plate with four larger and four alternating smaller pores. Feet sixteen to twenty, slender,
curved, divergent ; four primary feet larger, twice to three times as long as the shell and the other
feet.

Dimensions. — Shell 0'08 long, O'l broad ; feet O'l to 0'2 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

REPORT ON THE RADIOLARLA. 1071

5. Gorgospyris eurycolpos, n. sp. (PL 87, fig. 5).

Shell nut-shaped, rough, with deep sagittal stricture and irregular, roundish pores ; two to
three pairs of larger annular pores on each side of the stricture. Basal plate with four large
collar pores. Feet eight, short, triangular, vertical, about one-fourth as long as the shell.

Dimensions. — Shell 0'08 long, 013 broad ; feet 0'02 long.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

6. Gorgospyris liriope, n. sp. (PI. 87, fig. 6).

Shell nut-shaped, thorny, with sharp sagittal stricture and irregular, roundish pores. Two
pairs of larger annular pores on each side of the ring. Basal plate with two very large circular
pores only. Eight to ten short feet vertical, about one-fourth as long as the shell, with an elegant
papillate knob at the distal end.

Dimensions. — Shell 0'07 long, 01 broad ; feet 0'02 long.

Habitat. — South Atlantic, Station 323, depth 1900 fathoms.

7. Gorgospyris lamellosa, n. sp.

Shell nut-shaped, tuberculate, with subregular circular pores. Basal plate with four larger
and four alternate pairs of smaller pores. Feet fifteen to twenty -five, broad, lamellar, vertical,
truncate, about as long as the shell, of irregular size and form, very variable.

Dimensions. — Shell 0'07 long, 01 broad ; feet 0'05 to 01 long.

Habitat. — Fossil in Barbados.

Subgenus 2. Thamnospyris, Haeekel, 1881, Prodroruus, p. 443.
Definition. — Feet divided or branched.

8. Gorgospyris schizopodia, n. sp. (PI. 87, fig. 4).

Shell hemispherical, smooth, with slight sagittal stricture and small regular, circular pores.
Basal plate with four large central and a circle of small pores. Feet fifteen to twenty, broad,
lamellar, confluent at the base, about as long as the shell, irregularly divided or forked.

Dimensions. — Shell 0'06 long, 0'08 broad ; feet 0'05 to 0'08 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

9. Gorgospyris thamnopodia, n. sp.

Thamnospyris thamnopodia, Haeekel, 1881, Prodromus, p. 443.

Shell nut-shaped, tuberculate, with deep sagittal stricture and irregular, roundish pores. Basal
plate with numerous small pores. Feet twenty to thirty, slender, curved, divergent, twice to three
times as long as the shell, irregularly branched.

Dimensions. — Shell 0'08 long, 012 broad ; feet 015 to 0'25 long.

Habitat.*— Indian Ocean (Madagascar), Eabbe, surface.

1072 THE VOYAGE OF H.M.S. CHALLENGER.

Subfamily 8. CIRCOSPYRIDA, Haeckel, 1881, Prodromus, p. 443.
Definition. — Z ygospyrida apoda, without descending basal feet.

Genus 467. Circospyris,1 Haeckel, 1881, Prodromus, p. 444.
Definition. — Z ygospyrida without basal feet, with an apical horn.

The genus Circospyris and the following closely allied genus Dictyospyris
represent together the small subfamily Circospyrida, differing from all other Zygospyrida
in the absence of feet on the basal face. They have probably arisen from the Tripos-
pyrida (Tripospyris) by reduction and loss of the feet (in the same way as the
eradiate Cyrtoidea from the triradiate). But it is also possible that many of the
Circospyrida (if not all) are derived directly from the Semantida (Clathrocircus) by
the closing of the two lateral. openings and by completing the framework.

1. Circospyris nucula, n. sp. (PL 95, fig. 13).

Shell nut-shaped, compressed, smooth, with prominent sagittal ring. On each side of the ring
three to four pairs of very large annular polygonal pores. Lateral pores small and numerous,
roundish. Basal plate with two large pores only. Horn slender, conical, shorter than half the shell.

Dimensions. — Shell (Ml long, CMS broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Circospyris gigas, Haeckel.

Dictyospyris gigas, Ehrenberg, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. xix. fig. 6.

Shell nut-shaped, tuberculate, with distinct sagittal stricture. On each side of the ring four
pairs of larger annular pores. Lateral pores roundish, smaller. Basal plate with four large
central and a circle of eight to twelve smaller peripheral pores. Horn cylindrical, about half as
long as the shell (in the inverted figure of Ehrenberg directed downwards).

Dimensions. — Shell 01 to 015 long, 015 to 0'2 broad; horn 0'05 to 0'08 long.

Habitat. — Fossil in Barbados.

3. Circospyris tridentata, Haeckel.

Dictyospyris tridentata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xix.
fig. 10, a, b.

Shell nut-shaped, smooth, with sharp sagittal stricture. On each side of the ring two pairs of
large annular pores. Lateral pores roundish, smaller. Basal plate with six large pores. Horn
slender, cylindrical, about as long as the shell, with three sharp teeth at the distal end.

Dimensions. — Shell 0'03 long, 0'05 broad ; horn 0'03 long.

Habitat. — Fossil in Barbados.

1 Cvrcoepyris = Basket with a ring ;

REPORT ON THE RADIOLARIA. 1073

Genus 468. Dictyospyris,1 Ehrenberg, 1847, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 54.

Definition. — Z ygospyrida without basal feet, and without coryphal horns.

The genus Dictyospyris, the last and simplest of the twenty-eight genera of
Zygocyrtida, may be regarded either as a primordial ancestral form of this large family,
or more probably as the last and most reduced form of it. In the former case the
total absence of coryphal horns and basal feet is primary, in the latter case secondary,
effected by phylogenetic reduction and loss, .But it is also possible that in one
part of the numerous species of this genus the former case, and in another the latter
takes place, and that one part of Dictyospyris may be directly developed from the
Semantida or Coronida (the lattice shell becoming complete), another part arising from
the Tripospyrida or Dipospyrida (the horns and feet becoming lost).

Subgenus 1. Dictyospyrantha, Haeckel.

Definition. — Basal plate with two large pores only (the primary jugular pores of
Semantis).

I. Dictyospyris distoma, n. sp. (PL 89, figs. 11, 12).

Shell nut-shaped, smooth, or somewhat tuberculate, with deep sagittal stricture. Pores not
numerous, large, roundish-polygonal ; three pairs of large annular pores on each side of the ring.
Basal plate with two very large pentagonal roundish collar pores.

Dimensions. — Shell 0'06 long, 0'08 broad.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

2. Dictyospyris stalactites, n. sp. (PL 89, fig. 7).

Shell nut-shaped, covered with irregular ramified tubercles (like stalactites), with deep sagittal
stricture. Pores not numerous, large, irregular, roundish. Two pairs of large triangular pores on
each side of the ring (the inferior larger). Basal plate with two very large semicircular collar
pores.

Dimensions. — Shell 0'07 long, 0'09 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms ; also fossil in Barbados.

1 Dictyospyris = Net-basket; 3«Ti/o», ovrvi>is.
(ZOOL. OHALL. EXP. — PART XL. — 1886.) Er 135

1074 THE VOYAGE OF H.M.S. CHALLENGER.

3. Dictyospyris biloba, n. sp.

Shell subspherical, tuberculate, with slight sagittal stricture. Pores very numerous, small,
circular. No larger pores on either side of the ring. Basal plate with two very large circular
pores, surrounded by a circle of smaller pores.

Dimensions. — Shell 0'07 long, 0'08 broad.

Habitat.— North Pacific, Station 253, depth 3125 fathoms.

Subgenus 2. Dictyospyrella, Haeckel.

Definition. — Basal plate with three large collar pores (two paired posterior cardinal
pores and an odd anterior sternal pore).

4. Dictyospyris triomma, n. sp.

Shell nut-shaped, smooth, with deep sagittal stricture. Pores not numerous, large, polygonal
roundish, two pairs of very large annular pores on each side of the ring. Basal plate with three
large triangular pores. No free internal procolumella.

Dimensions. — Shell 0'06 long, 0'09 broad.

Habitat. — Indian Ocean, Zanzibar (Pullen), depth 2200 fathoms.

5. Dictyospyris tristoma, Ehrenberg.

Dictyospyris tristoma, Ehrenberg, 1875, Abhaudl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xix.
fig. 9.

Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores numerous, irregular, roundish.
Three pairs of larger annular pores on each side of the ring. Basal plate with three large semi-
circular pores (the sternal odd pore apparently halved by an internal free procolumella).

Dimensions. — Shell 0'05 long, 0'08 broad.

Habitat. — Fossil in Barbados and Sicily (Caltanisetta).

6. Dictyospyris triloba, Ehrenberg.

Dictyospyris triloba, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xix. fig. 8.

Shell nut-shaped, spinulate, without external stricture, but with a complete internal sagittal
ring. Pores numerous, subregular circular ; no larger annular pores. Basal plate with three large,
heart-shaped two-lobed collar pores.

Dimensions. — Shell 0'05 long, 0'07 broad,

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1075

7. Dictyospyris gigas, Biitschli.

Dictyospyris gigas, Butschli, 1880, Zeitschr. f. wiss. Zool., vol. xxxvi., p. 539, Taf. xxxii.
fig. 14a, 146.

Shell subspherical, smooth, with a half (ventral) sagittal stricture, and a nearly complete internal
ring. Pores very numerous and small, circular. No larger annular pores. Basal plate with three
large collar pores (the sternal odd pore apparently divided into two jugular pores by the visible free
procolumella. (Compare Circospyris gigas, p. W7 2 = Dictyospyris gigas, Ehrenberg).

Dimensions. — Shell O'l long, 0'14 broad.

Habitat. — Fossil in Barbados.

Subgenus 3. Dictyospyrissa, Haeckel.

Definition. — Basal plate with four large collar pores (two larger posterior cardinal
and two smaller anterior jugular pores).

8. Dictyospyris fenestra, Ehrenberg.

Dictyospyris fenestra, Ehrenberg, 1875, Abhandl. d.k. Akad. d. Wiss. Berlin, p. 68, Taf. xix. fig. 11.

Shell nearly cubical, smooth, without external sagittal stricture. Internal sagittal ring complete.
Pores small, roundish ; on each side of the ring two crossed pairs of large, square, equal, annular
pores. Basal plate also with four longer pores of nearly equal size.

Dimensions. — Shell 0'05 long, 0'07 broad.

Habitat. — Fossil in Barbados.

9. Dictyospyris tetrastoma, Ehrenberg.

Dictyospyris tetrastoma, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xix.
fig. 12.

Shell nut-shaped, tuberculate, with slight sagittal stricture. Pores numerous, irregular, roundish.
No larger annular pores. Basal plate with four large ovate collar pores (the two cardinal twice as
large as the two jugular pores).

Dimensions. — Shell O'Oo long, 0'07 broad.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific ; also fossil in Barbados and Sicily.

10. Dictyospyris spinulosa, Ehrenberg.

Dictyospyris spinulosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xix.

fig. 13.
ICeratospyris lorealis, Bailey, 1856, Amer. Journ. of Science and Arts, vol. xxii. pi. i. fig. 3.

Shell nut-shaped, spinulate, without external stricture, with an internal free sagittal ring. Pores
numerous, irregular, roundish ; on each side of the ring two pairs of very large square pores.
Basal plate with four large collar pores.

1076 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Shell 0'07 long, 0'08 broad.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms ; also fossil in
Barbados.

11. Dictyospyris mammillaris, n. sp. (PI. 89, figs. 9, 10).

Shell mammillate, nut-shaped, with deep sagittal stricture. Mammilla? of the surface hemi-
spherical, with a conical apex. Pores not numerous, large, roundish. Two pairs of large pores on
each side of the ring. Basal plate with four large pores.

Dimensions. — Shell 0'06 long, 0'08 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

12. Dictyospyris anthophora, n. sp. (PI. 89, fig. 8).

Shell tuberculate, nut-shaped, nearly cubical, without external' sagittal strictures. Pores not
numerous, large, polygonally roundish. Bars between them compressed, elevated, with large, cam-
panulate or flower-like tubercles on the nodal points. Basal plate with four large pores.

Dimensions. — Shell 0'07 long, 0'09 broad.

Habitat. — North Atlantic, Station 349, depth 2450 fathoms.

13. Dictyospyris quadriloba, n. sp.

Shell nut-shaped, smooth, with deep sagittal stricture. Pores numerous, small, circular, on
each side of the ring three to four times as large as on the lateral sides. Basal plate with four
very large collar pores and a circle of twenty to twenty-five very small peripheral pores.

Dimensions. — Shell 0'08 long, Oil broad.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

14. Dictyospyris messanensis, J. Midller.

Dictyospyris messanensis, J. Miiller, 1858, Abhancll. d. k. Akad. d. Wiss. Berlin, p. 46, Taf. ii.

fig. 8.
Dictyospyris messanensis, Haeckel, 1862, Monogr. d. Kadiol., p. 291.

Shell nut-shaped, spinulate, with deep sagittal stricture. Pores numerous and small, irregular
roundish. No larger annular pores on the sides of the ring. Basal plate with four large, nearly
equal, pear-shaped collar pores.

Dimensions. — Shell 0'06 long, 0'08 broad.

Habitat. — Mediterranean ; Messina, surface.

Subgenus 4. Dictyospyromma, Haeekel.
Definition. — Basal plate with six or more collar pores.

REPORT ON THE RADIOLARIA. 1077

15. Dictyospyris hexastoma, n. sp.

Shell nut-shaped, tuberculate, with deep sagittal stricture. Pores small, irregular, roundish.
Three pairs of larger pores on each side of the ring. Basal plate with six large pores; the middle
pair (cardinal) twice as large as the anterior (jugular) and the posterior (cervical).

Dimensions. — Shell 0-08 long, 012 broad.

Habitat. — Fossil in Barbados.

16. Dictyospyris enneastoma, n. sp.

Shell ellipsoidal, smooth, without external sagittal stricture, but with an internal free sagittal
ring. Pores small and numerous, regular, circular. No larger annular pores. Basal plate with
nine pores, three larger interradial alternating with three pairs of adradial.

Dimensions. — Shell 0'07 long, Oil broad.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

17. Dictyospyris polystoma, n, sp.

Shell nut-shaped, mammillate, with distinct sagittal stricture. Pores small and numerous,
irregular, on each side of the ring three to five times as large as on the lateral sides. Basal plate
with twelve large pores (four central and four alternate pairs of peripheral).

Dimensions. — Shell 01 long, 014 broad.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

Family LIII. THOLOSPYRIDA, n. fam.
(PL 87, figs. 7-10 ; PI. 89, figs. 1-4 ; PL 95, figs. 14-16).

Definition. — S pyroidea with a galea, but without thorax ; the shell being
composed of the bilocular cephalis and of an aboral cupola or galea arising from its
coryphal face.

The family Tholospyrida differs from the preceding Zygospyrida, its ancestral
group, in the development of a galea, i.e., a fenestrated hemispherical or dome-shaped
cupola, which covers the upper face of the cephalis like a cap.

Only three species of this family have been hitherto described : Pylospyris (or
Spyridobotrys) trinacria, figured in my Monograph (1862), Pylospyris (or Lithopera)
denticulata, figured by Ehrenberg (1872), and Lophospyris (or Ceratospyris) acuminata,
figured by Hertwig (1879). Fourteen new species have been found in the collection
of the Challenger, which we dispose here among five genera. These may be derived
from corresponding genera of Zygospyrida by the development of a galea.

1078 THE VOYAGE OF H.M.S. CHiiLENGEE.

The number and disposition of the terminal feet around the basal plate do not vary
so much in the Tholospyrida as in the Zygospyrida. We find here only one genus
with three feet, Tholospyris (corresponding to Tripospyris) ; one genus with two
lateral feet, Lophospyris (corresponding to Dipospyris] ; and two genera with numerous
feet, the horned Sepalospyris and the hornless Tiarospyris (the former corresponding
to Petalospyris, the latter to Gorgospyris}. The fifth genus (Pylospyris) has no feet
at all, and may be derived from Circospyris among the Zygospyrida.

The cephalis exhibits in the Tholospyrida the same typical structure which we have
described above of all Spyroidea (compare p. 1017). The cupola or galea, arising
from its upper face, seems to be a secondary production, perhaps caused by an apical
growth of the central capsule, or in other cases by descending branches of the apical
horn, which cover the apical face of the calymma with protecting network.

Synopsis of the Genera of Tholospyrida.

I. Subfamily \ Three basal feet (two paired pectoral and

Lophospyrida. J an odd caudal), . . .469. Tholospyris.

Two or three basal (cortinar feet). Galea 1

with a horn. [ Two paired basal (pectoral) feet, . 470. Lophospyris.

II. Subfamily

Tiarospyrida.

Numerous basal feet in a corona (six to nine
or more).

Galea with a horn, . . .471. Sepalospyris.

Galea without a horn, . . . 472. Tiarospyris.

III. Subfamily )

Pylospyrida. /• Galea with a horn, . 473. Pylospyris.

No basal feet.

Genus 469. Tholospyris,1 Haeckel, 1881, Prodromus, p. 441.
Definition. — T holospyrida with three basal feet and an apical horn.

The genus Tholospyris is probably the common ancestral form of the Tholospyrida,
and has arisen from Tripospyris by development of a galea or cupola; this is composed
jf the apical horn, the lateral branches of which become connected with lateral spines
arising from the coryphal face of the cephalis, and of lattice-work developed between
the former and the latter. The three descending feet of the basal face are the typical
cortinar feet (one odd caudal and two paired pectoral), the same as in the old ancestral
genera Cortina, Plagoniscus, Tripospyris, &c.

Subgenus 1. Tlwlospyrium, Haeckel.
Definition. — Basal feet simple, neither forked nor branched.

1 Tholospyris = Basket with a cupola ; ta'Tioj, ami^ls-

REPORT ON THE RADIOLARIA. 1079

1. Tholospyris tripodiscus, n. sp. (PI. 89, fig. 1).

Shell campanulate, smooth, as broad as long, with deep sagittal stricture. Cephalis com-
pressed, with irregular roundish pores ; two or three pairs of larger annular pores on each side of
the ring. Basal plate with four large pores. Galea with two very large opposite holes (an
occipital and a frontal opening). A slender free perpendicular columella connects the uppermost
part of the sagittal ring with the strong three-sided pyramidal apical horn. All three feet of
equal length, half as long as the ring, three- sided, prismatic, divergent, with three dentated edges.

Dimensions. — Shell 0'13 diameter, ring O08 long, feet 0'05 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Tholospyris fenestrata, n. sp. (PI. 89, fig. 2).

Shell roundish polyhedral, smooth, with slight sagittal stricture. Cephalis nearly cubical, with
irregularly roundish pores ; two or three pairs of larger pores on each side of the ring. Basal plate
with two very large pores. Galea pyramidal, with two large occipital holes. Columella enclosed
in the dorsal wall of the galea, prolonged into an oblique pyramidal spine of the same length. Two
pectoral feet pyramidal, nearly vertical and as long as the ring, twice as long as the caudal foot.

Dimensions. — Shell 0'12 diameter, ring 0'07, pectoral feet 0'05 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Tholospyris galeata, n. sp.

Shell helmet-shaped, thorny, with deep sagittal stricture. Cephalis campanulate, with sub-
regular circular pores. Basal plate with three large pores. Galea hemispherical, separated from
the cephalis by a sharp horizontal stricture ; pores smaller. A slender free columella connects the
apex of the ring with the strong conical apical horn, which is half as long as the ring. All three
feet of equal length, divergent conical, as long as the horn.

Dimensions. — Shell 0'14 diameter, ring 0'09 long, feet 0'08 long.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

Subgenus 2. Tholospyridium, Haeckel.
Definition. — Basal feet forked or branched.

4. TJwlospyris ramosa, n. sp. (PI. 89, fig. 3).

Shell helmet-shaped, smooth, with deep sagittal stricture. Cephalis nearly spherical, with irre-
gularly polygonal pores ; four or five pairs of larger annular pores on each side of the strong angular
ring. Cupola flat, conical, with two pairs of larger pores. Columella enclosed in its dorsal wall,

1080 THE VOYAGE OF H.M.S. CHALLENGER.

bearing an irregularly branched horn. Caudal foot short conical, simple. Two pectoral feet half as
long as the shell, angular, subvertical, irregularly branched.

Dimensions, — Shell 015 diameter, ring 01 long, pectoral feet 0'07 long.

Habitat. — Central Pacific, Station.271, depth 2425 fathoms.

5. Tholospyris cupola, n. sp. (PL 89, fig. 4).

Shell pear-shaped or cupola-shaped, smooth, with slight sagittal stricture. Cephalis not
distinctly separated from the galea, as the ring in the uppermost part of the shell- wall becomes
obliterated. Pores irregularly polygonal, small and numerous. Basal plate with four large pores.
Apical horn and the three divergent feet, irregularly branched ; feet nearly as long as the shell,
about four times as long as the horn.

Dimensions. — Shell 014 diameter, ring 01 long, feet 012 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 470. Lophospyris,1 Haeckel, 1881, Prodromus, p. 443 (sensu emendato).
Definition. — T holospyrida with two lateral basal feet and an apical horn.

The genus Lophospyris differs from the preceding TJwlospyris, its probable ancestral
form, in the absence of the caudal foot, and therefore bears to it the same relation that
Dipospyris does to Tripospyris. The two pectoral feet are alone developed and are
placed opposite in the frontal plane. Lophospyris may also be derived from Dipospyris
by the formation of a galea.

1. Lophospyris dipodiscus, n. sp. (PL 95, fig. 14).

Shell ovate, spinulate, with sharp transverse coronal constriction. Cupola hemispherical, half as
large as the nut-shaped cephalis. Pores irregularly roundish, much larger on the sagittal constriction.
Apical horn pyramidal, about half as long as the shell. Two lateral feet cylindrical, strongly
curved, about as long as the shell, with some irregular branches ; together forming a nearly
complete circle.

Dimensions. — Shell 0'09 long, 0'08 broad; ring 0'04 long, feet 0'08 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

\

2. Lophospyris acuminata, Haeckel.

Ceratogpyris acuminata, K. Hertwig, 1879, Organism, d. Kadiol., p. 70, Taf. vii. fig. 2.

Shell campanulate, smooth, without external transverse stricture. Cupola conical, half as long
and broad as the nut-shaped cephalis. Pores irregularly roundish, on each side of the sagittal

1 Lophospyris = Basket with a crest ; Ao'Tof, aicutf;.

REPORT ON THE RADIOLARIA. 1081

strictures much larger. Basal plate with four large triangular pores. Apical horn slender,
prismatic ; its outer free part of the same length as the inner columella, and as the two lateral feet,
which are curved, shorter than half the ring.

Dimensions. — Shell 0'08 long, O09 broad; ring O'OG long; horn and feet 0'03 long.

Habitat. — Mediterranean, Messina (E. Hertwig).

3. Lophospyris comosa, n. sp.

Shell ovate, spiny, with deep transverse stricture. Cupola large, campanulate, nearly as long
and two-thirds as broad as the nut-shaped eephalis. Pores irregular, roundish, of little different size,
Basal plate with numerous (eight to twelve) similar pores. Apical horn large, nearly as long as the
shell, surrounded by a bunch of smaller divergent spines. Two lateral feet divergent, larger than
the shell, cylindrical ; at the distal end irregularly branched, at the base surrounded by some smaller
spines.

Dimensions. — Shell 015 long, Oil broad; ring 0-08 long; feet 0'2 long.

Habitat. — Western Tropical Pacific, Station 206, depth 2100 fathoms.

Genus 471. Sepalospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — T holospyrida with numerous basal feet (eight to twelve or
more). Galea with a horn.

The genus Sepalospyris has been derived from the similar Petalospyris by
development of a galea or cupola on the coryphal face of the eephalis, or from
Tholospyris by multiplication of the basal feet. The latter (in the two observed
species from twelve to twenty -five) form a regular corona around the basal plate.

1. Sepalospyris platyphylla, n. sp.

Shell ovate, rough, with sharp transverse stricture Cupola with delicate network, hemi-
spherical, about two-thirds as long and broad as the nut-shaped thorax. Pores of the latter
irregular, roundish ; two or three pairs of large pores on each side of the sagittal stricture.
Apical horn conical, half as long as the shell. Basal coronet with twelve to fifteen broad,
lamellar, truncate, vertical feet, somewhat shorter than the eephalis.

Dimensions.— Shell 012 long, 013 broad; ring 0'06 long; horn 0'04 ; feet 0'05 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Sepalospyris polyphylla, n. sp.

Shell campanulate, rough, with deep transverse stricture. Cupola hemispherical, about one-
third as long and broad as the nut-shaped thorax. Pores irregular, roundish, a little different in

1 Sepalospyris = Basket with leaves ; airs-afoot, »*i/j/f.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 136

1082 THE VOYAGE OF H.M.S. CHALLENGER.

size. Apical horn pyramidal, about as long as the shell. Basal coronet with twenty to twenty-
five slender, lamellar, pointed, vertical feet, longer than the shell.

Dimensions. — Shell Oil long, 012 broad ; ring 0'07 long; horn 01 ; feet 012 to 018 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 472. Tiarospyris,1 Haeckel, 1881, Prodromus, p. 443.

.Definition. — Thol o spy r ida with numerous basal feet (eight to twelve or
more). Galea without a horn.

The genus Tiarospyris has probably been derived from the preceding Sepalospyris
by reduction and loss of the free apical horn ; it therefore bears to it the same
relation that the similar Gorgospyris does to Petalospyris.

1. Tiarospyris pervia, n. sp. (PL 87, fig. 7).

Shell nut-shaped, smooth, with deep sagittal stricture. Cephalis on the lateral sides with
numerous small roundish pores, on each side of the ring with a pair of very large holes. Basal
plate with two large collar pores. Cupola flat, cap-shaped, with two large parietal pores above
the ring. Coronet with eight conical, slightly divergent feet, about one-fourth as long as the shell.

Dimensions. — Shell 0'08 long, 01 broad ; ring 0'06 long ; feet 0'02 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

2. Tiarospyris galea, n. sp.

Shell helmet-shaped, with deep sagittal stricture. Cephalis with irregular, polygonal pores ; on
each side of the ring two pairs of larger annular pores. Basal plate with four large pores.
Cupola high, conical, nearly as long as the cephalis, separated from it by a distinct coronal
stricture. Basal coronet with twelve to sixteen slender curved divergent feet, nearly as long as
the shell.

Dimensions. — Shell 016 long, 012 broad; ring 01 long; feet 015 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Tiarospyris mitra, n. sp. (PL 87, figs. 9, 10).

Shell subspherical, smooth. Cephalis on the lateral sides with small roundish, double-
contoured pores, on each side of the ring with three to five pairs of larger pores, each of which
is closed by a thin fenestrated lamella (different on the frontal face, fig. 9, and the dorsal face,
fig. 10). Cupola flat, cap-shaped, separated by a distinct coronal stricture, with smaller pores.
Basal coronet with ten to twelve short conical convergent feet.

Dimensions. — Shell Oil long, 012 broad; ring 0'04 long; feet 0'02 long.

Habitat. — West Tropical Pacific, Station 225, depth 4475 fathoms.

1 Tiarospyris— Basket with a cap ;

REPORT ON THE RADIOLARIA. 1083

4. Tiarospyris amphora, n. sp. (PI. 87, fig. 8).

Shell amphora-shaped, in the upper half smooth, in the lower spiny, without external sagittal
stricture. Cephalis subspherical, with a small numher of irregular, large, roundish pores, which
are closed by a thin fenestrated lamella. Cupola flat, cap-shaped, with numerous small pores.
Base covered with numerous conical divergent feet of different sizes, the largest one-third as long
as the shell. Internal sagittal ring ovate, nearly free.

Dimensions. — Shell 014 long, 013 broad ; ring 01 long ; feet 0'04 long.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

Genus 473. Pylospyris^ Haeckel, 1881, Prodromus, p. 443.
Definition. — T holospyrida without basal feet, with an apical horn.

The genus Pylospyris was first known from a Mediterranean species, called by me,
in 1862, Spyridobotrys trinacria. As this name was given erroneously, on the supposi-
tion of a near relation to the Botryodea ( = Polycyrtida), I changed it afterwards to
Pylospyris. This genus differs from the other Tholospyrida in the total absence of
basal feet, and may therefore be derived either from them by reduction of the feet,
or from Dictyospyris by formation of a galea.

1. Pylospyris denticulata, Haeckel.

Lithopera denticulata, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. xii.

II. fig. 7.
Lithobotrys denticulata, Ehrenberg, 1844, Monatsber. d. Akad. Berlin, p. 203.

Shell spinulate, with slight coronal and deep sagittal constriction, with irregular, roundish pores
of variable size. Galea hemispherical, about half as long and broad as the nut-shaped cephalis.
No symmetrically disposed larger pores.

Dimensions. — Galea 0'04 long, 0'06 broad ; cephalis 0'08 long, 01 broad.

Habitat. — Antarctic Ocean, Ehrenberg. (Included in the ice.)

2. Pylospyris trinacria, Haeckel.

Spyridobotrys trinacria, Haeckel, 1862, Monogr. d. Radiol., p. 341, Taf. xii. figs. 8, 9.

Shell tuberculate, with sharp coronal and sagittal stricture. Galea campanulate, with very
small circular pores, and a short conical apical horn of the same length. Cephalis nut-shaped, with
large, irregular, roundish pores ; two pairs of larger annular pores on each side of the sagittal ring,
also four larger pores in the basal plate.

Dimensions. — Galea 0'03 long, 0'04 broad ; cephalis OD4 long, 0'07 broad.

Habitat. — Mediterranean, Messina, surface.

! Pylospyris = Basket with gates ;

1084 THE VOYAGE OF H.M.S. CHALLENGER.

3. Pylospyris candriensis, n. sp. (PL 95, fig. 16).

Shell rough, with deep coronal and slight sagittal constriction. Galea hemispherical, with
numerous small irregular, roundish pores, about half as long as the cephalis, with a slender conical
horn of twice the length. Cephalis nut-shaped, with larger roundish pores of very unequal size,
three pairs of larger pores on each side of the ring. Basal plate with two larger pores.

Dimensions. — Galea 0'03 long, 0'08 broad ; cephalis 0'06 long, Oil broad.

Habitat. — North Atlantic, Canary Islands, surface.

Family LIV. PHOEMOSPYRIDA, Haeckel (sensu emendato) (PL 83, figs. 13-15 ;

PL 95, figs. 17-19).
Phormospyrida, Haeckel, 1881, Prodromus, p. 442.

Definition. — S pyroidea with a thorax, without galea; the shell composed of the
bilocular cephalis and of a simple thorax arising from its basal face.

The family Phormospyrida differs from the Zygospyrida, their ancestral group,
in the development of a thorax, or a second fenestrated shell -joint, which arises from, the
lower face of the cephalis. It corresponds, therefore, to the Dicyrtida among the
Cyrtoidea, and may perhaps be, wholly or partially, the ancestral group of the latter.
When the sagittal ring and the longitudinal constriction of the cephalis disappear,
the Phormospyrida pass over into the Dicyrtida.

Only three species of this family have been hitherto known, which were found fossil
in Barbados, and described by Ehrenberg (1875) as Lithobotrys stiligera and Petalospyris
confluens, and by Biitschli (1882) as Petalospyris anthocyrtoides. Fifteen other species
are found in the Challenger collection, which we dispose here among five genera.

Two of these five genera (the horned Acrospyris and the hornless Phormospyris)
possess the three typical basal feet of Cortina and Tripospyris, and may be derived
from these genera by the development of network between the bases of the feet. The
three other genera possess numerous feet, and may be derived in the same way from
the Polyspyrida ; the apical face differs in the three genera, in Dcsmospyris it is
hornless, in Patagospyris it bears an apical horn, and in Rhodospyris three horns
(an apical and two lateral or frontal).

The cephalis in the Phormospyrida exhibits the same typical structure, which we
have described above, of all Spyroidea (compare, p. 1017). The thorax or the second
joint of the shell arises by reticular connection of the bases of the basal feet, and
represents a cylindrical or truncate-conical joint in the polypodal forms, or a three-sided
joint in the tripodal forms. The terminal aperture or the mouth of the thorax is
constantly open, and surrounded by the free ends of the feet.

Acros rida

REPORT ON THE RADIOLARIA.

Synopsis of the Genera of Phormospyrida.

apical

1085

cros ra

Three basal cortinar feet (one odd caudal [ N ical h
and two paired pectoral).

II Subfamily

Khodospynda.

Numerous basal feet in a corona (nine to
twelve or more).

°De apical h°rn' "
Thfee .^ h

No apical horn, .

475. Phorm)spyris.

476' Pataff08Py™.
477_ Rhodospyris

478. Desmospyris.

Subfamily 1. ACROSPYRIDA, Haeckel, 1881, Prodromus, p. 441 (sensu emendato).

Definition. — P hormospyrida with three basal feet (an odd caudal and two
paired pectoral).

Genus 474. Acrospyris,1 Haeckel, 1881, Prodromus, p. 441.
Definition. — P hormospyrida with three basal feet and one apical horn.

The genus Acrospyris is probably the oldest and most primitive among the Phor-
mospyrida, perhaps the original ancestral form of this family. It has been derived
from Tripospyris by the development of lattice-work between the three basal feet, forming
a second joint or thorax. It has also therefore a close relation to the simplest forms of
the triradiate Dicyrtida: Dictyophimus, Clathrocanium, &c. It differs from these in
the distinct sagittal constriction of the cephalis, which divides it into two lateral loculi.

1. Acrospyris clathrocanium, n. sp. (PL 95, fig. 17).

Shell tuberculate, with distinct collar and deep sagittal stricture. Cephalis nut-shaped, with
numerous irregular, roundish pores ; three pairs of larger annular pores on each side of the ring.
Basal plate with four larger pores (two major cardinal and two minor jugular pores). Apical horn
slender, pyramidal, curved, about as long as the shell, with three recurved short spines. Thorax
three-sided, about twice as large as the cephalis, with three large basal holes and a broad riband
with numerous smaller holes ; three ribs between them stout, pyramidal, strongly curved, prolonged
into three convergent crescentic feet.

Dimensions. — Cephalis 0'08 long, Oil broad; thorax 014 long, 016 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Acrospyris dictyophimus, n. sp.

Shell smooth. Cephalis and thorax of nearly the same structure and form as in the
preceding species ; it differs from the latter in the shape of the three stout basal feet, which are

1 Acrospyris = Basket with an apical spine ; ««?«, aw^i's-

1086 THE VOYAGE OF H.M.8. CHALLENGER.

straight, much longer than the thorax, divergent, and at the broader base irregularly fenestrated,
without three larger holes.

Dimensions. — Cephalis O05 long, 0'08 broad ; thorax 0'07 long, 012 broad.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

3. Acrospyris pyramidalis, n. sp.

Shell three-sided pyramidal, with slight collar stricture. Cephalis campanulate, with deep
sagittal stricture and stout ring, armed with a strong pyramidal horn of the same length. Thorax
shorter and broader, truncate. Pores irregular, roundish, scarce. Three feet divergent, three-sided
pyramidal, as long as the cephalis.

Dimensions. — Cephalis O'Oo long, 0-06 broad ; thorax 0'02 long, 0'08 broad.

Habitat. — Fossil in Barbados.

4. Acrospyris macrocephala, n. sp.

Shell spinulate, with deep sagittal and very deep collar stricture. Cephalis very large, nut-
shaped, twice as long and broad as the small, truncate, pyramidal thorax. Pores irregular, roundish.
Horn spindle-shaped, nearly as long as the cephalis ; the three divergent feet are of the same form
and size as the horn, and arise as three ribs from the deep collar stricture.

Dimensions. — Cephalis 01 long, 015 broad ; thorax 0'05 long, 0'09 broad.

Habitat. — Fossil in Barbados.

5. Acrospyris fragilis, n. sp.

Shell very thin-walled and fragile, with deep sagittal and collar strictures. Pores very small
and numerous, circular. Cephalis nut-shaped, nearly spherical, with a slender bristle-shaped horn
of the same length. Basal stricture with two large collar pores only (luminella). Thorax nearly
three-sided prismatic, longer than the cephalis, with three parallel ribs, prolonged into three slender,
long, bristle-shaped feet.

Dimensions. — Cephalis 0'05 long, 0'06 broad ; thorax 0'08 long, 0'06 broad.

Habitat. — North Pacific, Station 244, surface.

Genus 475. Phormospyris,1 Haeckel, 1881, Prodromus, p. 442 (sensu emendata).
Definition. — P hormospyrida with three basal feet, without apical horn.

The genus Phormospyris has been derived from Acrospyris, its ancestral form, by
reduction and loss of the apical horn ; it therefore bears to the latter the same relation
that Tristylospyris has to the ancestral Tripospyris.

1 Phormospyris = Wicker-basket ; <po^ft,o;. anvil's.

REPORT ON THE RADIOLARIA. 1087

1. Phormospyris tricostata, n. sp. (PL 83, fig. 15).

Cephalis nut-shaped, thorny, with deep sagittal and collar strictures, half as large as the
pyramidal thorax. Mouth of the latter dilated and ciliated, twice as hroad as the cephalis. Pores
irregular, polygonal, with thin bars. Three cylindrical, straight, divergent ribs descend in the wall
of the thorax, and are prolonged over the mouth into three short conical teeth.

Dimensions. — Cephalis 0'06 long, 0'09 broad; thorax 0'08 long, 016 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Phormospyris tridentata, n. sp. (PI. 95, fig. 18).

Cephalis nut-shaped, with deep sagittal and collar strictures, about twice as large as the thorax.
Mouth of the latter half as broad as the cephalis. Pores very small and numerous, subregular,
circular. Collar plate with four large triangular pores. In the wall of the thorax three vertical
prismatic ribs descend, which are prolonged over the mouth into three parallel feet of the same length.

Dimensions. — Cephalis 0'06 long, 0'08 broad ; thorax 0'04 long, 0'06 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Phormospyris trifoliata, n. sp.

Cephalis nut-shaped, with deep sagittal and collar strictures, smaller than the thorax. Mouth
of the latter nearly as broad as the cephalis. Pores circular, double-contoured, larger in the thorax
than in the cephalis. The thorax has no lateral ribs, but bears around the mouth three large
triangular lamellar terminal feet.

Dimensions. — Cephalis 0'04 long, 0-05 broad ; thorax 0'06 long, 0'05 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Subfamily 2. KHODOSPYRIDA, Haeckel.

Definition. — P hormospyrida with a corona of numerous (nine to twelve or
more) basal feet.

Genus 476. Patagospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — P hormospyrida with numerous basal feet (nine to twelve or more)
and an apical horn.

The genus Patagospyris and the two following closely allied genera differ from the
two preceding tripodal genera in the multiplication of the basal feet, and therefore
have to the latter the same relation that the Polyspyrida (Petalospyris) bear to the
Tripospyrida (Tripoerpyris). When the numerous basal feet of Petalospyris become
connected by lattice-work, Patagospyris arises.

1 Patagospyris = Basket with a patagium ; •Ki

1088 THE VOYAGE OF H.M.S. CHALLENGER.

1. Patagospyris confluens, Haeckel.

Petctlospyris confluens, Ehrenberg, 1885, AbhandL d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii.
fig. 5.

Shell tuberculate, with distinct sagittal and collar strictures. Pores irregular, roundish. Cephalis
nut-shaped, larger than the short truncate thorax. Horn conical, shorter than the cephalis.
Peristome with a coronet of twelve to fifteen short triangular feet, which are parallel and vertical,
slightly curved and shorter than the thorax.

Dimensions. — Cephalis 0'05 long, 0'07 broad ; thorax O03 long, 0'07 broad.

Habitat. — Fossil in Barbadoes.

2. Patagospyris lanceolata, n. sp.

Shell tuberculate, with slight sagittal and sharp collar strictures. Pores subregular, circular.
Cephalis subspherical, about as large as the truncate subcylindrical thorax. Horn spindle-shaped,
about as long as the cephalis. Peristome with a coronet of fifteen to twenty divergent lanceolate
lamellar feet, longer than the thorax.

Dimensions. — Cephalis 0'08 long, 0'09 broad; thorax 0'07 long, 0'07 broad.

Habitat, — Fossil in Barbados.

3. Patagospyris stiligera, Haeckel.

Liihobotrys stiligera, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iii.
fig. 17.

Shell smooth, hyaline, with deep sagittal and collar strictures. Pores very small and few.
Cephalis nut-shaped, bilobed, of the same breadth as the cylindrical thorax. Horn conical, about
as long as the cephalis. Peristome with a coronet of six to nine broad lamellar feet (in Ehrenberg's
figure broken off).

Dimensions. — Cephalis 0'04 to 0'05 diameter ; thorax 0'06 long, 0'05 broad.

Habitat. — Fossil in Barbados.

4. Patagospyris anthocyrtis, n. sp. (PL 95, fig. 19).

Shell smooth, with deep sagittal and deep collar strictures. Pores irregular, roundish, of various
sizes, numerous. Cephalis nut-shaped, with two inflated bosoms, about twice as broad as the short
cylindrical thorax. Horn stout, pyramidal, about as long as the cephalis. Peristome with a coronet
of fifteen to twenty parallel and vertical triangular lamellar feet, nearly as long as the thorax.

Dimensions. — Cephalis 0'05 long, O'l broad ; thorax 0'04 long, 0'06 broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 477. Rhodospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — P hormospyrida with numerous basal feet (nine to twelve or more),
and with three coryphal horns.

1 Rhodospyris = Rose-basket ; fiction anv^k-

REPORT ON THE RADIOLARIA. 1089

The genus Rhodospyris differs from the preceding Patagospyris in the development
of three coryphal horns (one odd middle apical horn, and two paired frontal horns on
each of its sides), and therefore bears the same relation to the latter that the
similar Anthospyris does to Petalospyris. When the numerous basal feet of Antho-
spyris become connected by lattice-work, Rhodospyris arises.

1. Rhodospyris tricornis, n. sp. (PI. 83, fig. 13).

Cephalis nut-shaped, with deep sagittal stricture, and three short apical horns of half its length ;
the middle odd horn is straight, the two paired lateral horns are curved outwards. Thorax some-
what larger than the cephalis, dilated around the wide open mouth, with a coronet of twenty-five
to thirty slender basal feet, which are slightly curved and convergent, about as long as the thorax.
Pores small, numerous and circular.

Dimensions. — Cephalis 0'05 long, 0'07 broad ; thorax 0'06 long, 0'08 broad ; horns 0'02 long,
feet 0-06 long.

Habitat. — Indian Ocean, Madagascar (Kabbe), surface.

2. Rhodospyris triceros, n. sp.

Cephalis nut-shaped, with deep sagittal and deep collar stricture, and with three stout divergent '
horns of nearly equal length. Thorax cylindrical, twice as long as the cephalis, and of the same
breadth, with a coronet of twelve to sixteen broad, lamellar, rectangular, perpendicular feet around
the mouth, about as long as the cephalis. Pores rather large, subregular, circular.

Dimensions. — Cephalis 0'06 long, 0'08 broad ; thorax 0'12 long, 0'09 broad.

Habitat. — Indian Ocean, Singapore (Trebing), surface.

Genus 478. Desmospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — P hormospyrida with numerous basal feet (nine to twelve or more),
without a coryphal horn.

The genus Desmospyris differs from the two preceding polypodal genera in the com-
plete absence of horns on the coryphal face of the cephalis. It therefore corresponds to
Gorgospyris among the Zygocyrtida, and arises when the numerous basal feet of the
latter become connected by lattice-work.

1. Desmospyris mammillata, n. sp. (PI. 83, fig. 14).

Shell mammillate, with deep sagittal and slight collar constriction. Pores irregular, roundish.
Cephalis nut-shaped, larger than the inversely conical thorax, and twice as broad as the constricted

1 Desmospyris = Basket with a band or string ; 'biapo;, aicv^l;.
(ZOOL. OHALL. EXP. — PAKT XL. — 1886.) Er 137

1090 THE VOYAGE OF H.M.S. CHALLENGER.

mouth. Coronet of the peristome with twelve to fifteen short conical convergent feet, shorter
than half the thorax.

Dimensions. — Cephalis 0'06 long, O09 broad ; thorax 0'04 long, 0'06 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Desmospyris cyrtocolpos, n. sp.

Shell smooth, with deep sagittal and collar strictures. Pores subregular, circular, double-con-
toured, very small and numerous. Cephalis nut-shaped, larger than the short truncate thorax.
Coronet with eighteen to twenty- four slender, irregular, pointed, convergent feet, about twice as long
as the thorax.

Dimensions. — Cephalis 0'08 long, 012 broad ; thorax 0'04 long, 01 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 44*75 fathoms.

3. Desmospyris anthocyrtoides, Haeckel.

Petalospyris anthocyrtoides, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. pp. 533, 539,
Taf. xxxii. fig. 19, a-c.

Shell tuberculate, with slight sagittal and sharp collar strictures. Pores subregular, circular.
Cephalis nut-shaped, larger than the short truncate thorax. Coronet wiih fifteen to twenty short
conical, parallel and vertical feet, about as long as the thorax.

Dimensions. — Cephalis 0'06 long, 0'09 broad; thorax 0~02 long, 0'07 broad.

Habitat. — Fossil in Barbados.

4. Desmospyris carpocanium, n. sp.

Shell smooth, with slight sagittal and slight collar strictures. Pores subregular, circular, small
and numerous. Cephalis carnpanulate, smaller than the ovate thorax. Coronet with fifteen to
twenty irregular lamellar feet, which are longer than the thorax, pointed, nearly vertical and
parallel.

Dimensions — Cephalis 0'05 long, 0'08 broad ; thorax 0'07 long, 01 broad.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

Family LV. ANDROSPYRIDA, n. fam. (PL 88-90).

Definition. — S pyroidea with galea and thorax ; the shell composed of a bilocular
cephalis and of two secondary joints, a galea arising from its upper face, and a thorax
arising from its lower face.

REPORT ON THE RADIOLARIA. 1091

The family Androspyrida differs from the three preceding families of S p y r-
o i d e a in the three-jointed shell, in which the galea of the Tholospyrida and the thorax of
the Phormospyrida are combined ; it may therefore be derived from the latter by develop-
ment of a galea, or from the former by formation of a thorax. The common ancestral
group of these three families is probably the Zygospyrida. But it may be that a
part of the Androspyrida has originated directly from the Stephoidea.

Two species only of this family were hitherto known, Amphispyris reticulata
(figured, in 1872, by Ehrenberg, as Dictyospyris} and Sphcerospyris sphcera (described, in
1882, by Biitschli, as Dictyospyris). Thirty new species were found in the collection
of the Challenger, and are here disposed in seven genera. But perhaps these may
represent three different families, which we here enumerate as subfamilies ; the Lampros-
pyrida, Perispyrida, and Nephrospyrida.

The Lamprospyrida, the first subfamily, are tripodal Spyroidea with galea and
thorax ; they may therefore be regarded as a combination of Tholospyris and Acrospyris.
In the simpler form, Androspyris (PI. 83, fig. 8), the network of the shell is simple, and
allows a very clear recognition of the internal structure. In the splendid Lamprospyris,
derived from it (PL 89, figs. 13, 14) the delicate network is more or less spongy. The
large apical horn is branched and fenestrated in the latter and simple in the former.

The Perispyrida, the second subfamily, possess no free apophyses, but a three-jointed
shell with two distinct transverse strictures, an upper mitral and a lower collar stricture.
The network of this shell is incomplete in Amphispyris (PI. 88, figs. 2-7), being
developed only in the frontal or lateral perimeter, thus making it probable that this
subfamily may have arisen directly from the Tympanida (Toxarium, PL 88, fig. 1 ;
PL 93, figs. 18-20). The network of Tricolospyris (PL 88, figs. 8-11) is complete, of
another shape in the cephalis than in the galea and thorax; it is doubled or spongy in
Perispyris (PL 88, figs. 12, 13).

The Nephrospyrida, the third subfamily, contains two very different genera only,
each of which may represent a separate family. Sphcerospyris (PL 83, fig. 4) possesses
a spherical or subspherical lattice-shell, the central part of which includes a sagittal ring,
connected with the inner face of the sphere by a number of paired apophyses, correspond-
ing to those of Lithocircus ; it may be easily confounded with some Sphseroidea
(Carposphcera), but the enclosed ring leaves no doubt as to its true origin. Nephrospyris
(PL 90) has a flat discoidal shell of considerable size, usually kidney-shaped or cordate,
with a deep sagittal incision at the base, indicating the region where the pseudopodia
are protruded from the porochora. The violin-shaped central capsule has two large
lateral lobes on each side of the including sagittal ring, and the transverse nucleus is
perpendicular to its sagittal plane (PL 90, figs. 7, 10). Sphcerocircus as well as Nephro-
spyris have probably arisen independently from the Stephanida.

1092

THE VOYAGE OF H.M.S. CHALLENGER.

Synopsis of the Genera of Androspyrida.

I. Subfamily

Lamprospyrida.
Three free basal feet.

( Lattice-work simple, not
spongy.

II. Subfamily

Perispyrida.

No free basal feet. Shell
three-jointed.

III. Subfamily

Nephrospyrida.
No free basal feet. Shell
spherical or discoidal.

Lattice-work wholly
partly spongy.

or

Shell with two transverse
coronal strictures (one
superior mitral and one
inferior collar stricture).

Apical horn usually simple,
not fenestrated,

{Apical horn usually branched
and fenestrated, .

Lattice-work only complete in
the frontal ring,

Lattice-work complete on all
sides,

[ Lattice- work double orspongy,

1 Shell spherical orsubspherical,
.
Shell discoidal, kidney-shaped
or subcircular,

479. Androspyris.

480. Lamprospyris.

481. AmpTiispyris.

482. Tricolospyris.

483. Perispyris.

484. Sphcurospyris.

485. Nephrospyris.

Subfamily 1. LAMPROSPYRIDA, Haeckel.

Definition.— A ndrospyrida with three free basal feet {an odd posterior caudal
foot and two paired anterior pectoral feet).

Genus 479. Androspyris,1 n. gen.

Definition. — A ndrospyrida with three free basal feet and a simple apical horn ;
lattice- work of the three-jointed shell simple, not spongy.

The genus Androspyris is probably the most original form of the Androspyrida, and
represents, together with the following Lamprospyris, the subfamily of Lamprospyrida,
which always possess three free basal feet, an odd posterior or caudal foot, and two
paired anterior or pectoral feet. It may be derived either from Acrospyris by develop-
ment of a cupola, or from Tholospyris by development of a thorax ; the common ancestral
form of these three typical genera is, no doubt, Tripospyris. Some species of
Androspyris reach a considerable size and are distinguished by a peculiar external form
resembling somewhat a human figure.

1. Androspyris homunculus, n. sp.

Shell thorny, with two deep transverse constrictions and irregular polygonal pores. Galea
subspherical, with a strong pyramidal oblique horn, about two-thirds as large as the cephalis, which
has the form of a human thorax, includes a strong ovate sagittal ring, and bears on each side a
stronger lateral spine. Thorax short and broad, prolonged into three latticed divergent feet ; the

1 Androspyris = Man-like wicker basket ; **>}{, e

EEPORT ON THE RADIOLARIA. 1093

two lateral (pectoral) feet are like the legs of a human body, and are twice as long as the cephalis
and as the tail-like caudal feet. (The whole shell exhibits a curious similarity to a human
figure, more than in the following nearly allied species.)

Dimensions. — Length of the shell (including horn and feet) 0'4, breadth 01 to 015.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

2. Androspyris anthropiscus, n. sp. (PI. 83, fig. 8).

Shell rough, with two distinct transverse constrictions and irregular polygonal pores. Galea
ovate, with a slender conical oblique horn, about as large as the cephalis, which exhibits a
deep longitudinal furrow in the sagittal dorsal line. Thorax half as long, prolonged into three
short latticed feet ; the terminal spines of the two lateral feet are vertical and parallel, that of the
caudal foot larger, directed obliquely backwards.

Dimensions. — Length of the shell (including horn and feet) 0'35, breadth O'l to 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Androspyris pithecus, n. sp. (PL 95, fig. 20).

Shell smooth, with two slight transverse constrictions. Galea conical, with a short conical
horn, longer than the nut-shaped cephalis. Thorax with three nearly vertical and parallel feet of
equal length. Pores in the galea and thorax very small and numerous, circular, in the cephalis
much larger, irregular, roundish.

Dimensions. — Length of the shell (including horns and feet) 0'25, breadth 0'06 to 0'08.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Androspyris aptenodytes, n. sp.

Shell smooth, with two slight transverse constrictions and irregular, roundish pores. Galea
hemispherical, with a short conical horn, about as large as the roundish cephalis and half as large
as the ovate thorax The three feet arise immediately beyond the collar stricture, are equal,
divergent, curved, about as long as the cephalis, and are not terminal (as in the three preceding
species), but lateral appendages of the thorax.

Dimensions. — Length of the shell 0'2, breadth 0'05 to 0'07.

Habitat. — Antarctic Ocean, Station 157, depth 1950 fathoms.

Genus 480. Lamprospyris,1 Haeckel, 1881, Prodromus, p. 447.

Definition.-:— An drospy rida with three free basal feet and a fenestrated apical
horn ; lattice-work of the three-jointed shell wholly or partly spongy.

The genus Lamprospyris differs from the preceding Androspyris, its ancestral form,
mainly in the higher development of the lattice-work of the large shell. Whilst this in

1 Lamprospyris = Splendid wicker-basket ;

1094 THE VOYAGE OF H.M.S. CHALLENGER.

the latter genus is a simple lattice-plate, it here becomes more or less spongy, and some-
times forms a very dense and delicate wickerwork. The apical horn and the three basal
feet are commonly also fenestrated. The two annular strictures, which separate the
cephalis from the conical cupola and the inflated thorax, are commonly not so distinct
as in the preceding genus. Some species belong to the largest Spyroidea and reach
more than half a millimetre in length.

1. Lamprospyris darwinii, n. sp. (PL 89. fig. 13).

Shell nearly pear-shaped, with two distinct annular strictures, and uneven papillate surface.
The total length is equal to twice the greatest breadth, and to seven times the length of the ring.
Apical horn free, irregularly branched and fenestrated, as long as the included columella beyond it.
The three diverging feet are strongly curved, S-shaped, and completely included by loose lattice-work.
In the middle of their length they give off a simple strong lateral branch. The loose arachnoidal
lattice-work is rather equally developed.

Dimensions. — Length of the entire shell (including the apophyses) 0'5, greatest breadth O25,
ring 0'07 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Lamprospyris lyellii, n. sp.

Shell slender, pear-shaped, very similar to the preceding species, but differing in the following
characters — the branched horn is much larger and twice as long as the columella ; the two annular
transverse strictures (separating the three joints) are deeper. The free lateral branches of the three
included feet are forked. Lattice-work looser than in the preceding species.

Dimensions. — Length of the entire shell 0'6, breadth O2, ring 0'09 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Lamprospyris huxleyi, n. sp. (PL 89, fig. 14).

Shell ovate, spiny, with two slight annular transverse strictures ; their length equal to one and a
half times the breadth, and up to seven times the length of the ring. Apical horn quite included
by the loose lattice-work of the large conical cupola, which is as long as the cephalis and thorax
together. The three slender feet are also included in the lattice-work and only one-third as long
as the shell, nearly vertical. Lattice-work much denser than in the two preceding species.

Dimensions. — Length of the shell 0'4, breadth 0'26, ring 0'06 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

4. Lamprospyris hooJceri, n. sp.

Shell ovato-conical, very similar to the preceding species, but smooth, not spiny. The apical
horn and the three feet are much longer, not included in the network, but freely prominent, half

REPOET ON THE EADIOLARIA. 1095

as long as the shell and nearly vertical, parallel. The arachnoidal lattice-work is much denser
in the middle third (cephalis) than in the upper third (cupola) or the lower third (thorax).

Dimensions. — Length of the shell (without appendages) 045, breadth 0'3, ring 0'08 long.

Habitat.-— Central Pacific, Station 270, depth 2925 fathoms.

5. Lamprospyris spenceri, n. sp.

Shell slender, ovate, very similar to the preceding species ; differing from it in the larger
cupola, which is as long as the cephalis and thorax together. The three feet are much shorter and
weaker, more divergent. This differs from all four preceding species in the possession of a large
double apical horn ; the two horns are strong, pyramidal, straight, strongly divergent, and as
long as the cupola.

Dimensions. — Length of the shell (without the appendages) 0'3, breadth 0'2, ring 0'05 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subfamily 2. PERISPYRIDA, Haeckel, 1881, Prodromus, p. 443.

Definition. — Androspyrida without free basal feet, with three distinct joints
separated by two parallel transverse strictures.

Genus 481. Amphispyris,1 Haeckel, 1881, Prodromus, p. 444.

Definition. — Androspyrida without free basal feet, with three distinct joints,
separated by two transverse strictures ; lattice-work of the shell only complete in the
frontal ring, with large open holes on the ventral and dorsal face.

The genus Amphispyris and the two following genera arising from it, represent
together the peculiar small subfamily of Perispyrida. This may have originated directly
from Toxarium (family Tympanida, PL 88, fig. 1 ; PI. 93, figs. 18-20), the large
holes between its arches and rings becoming filled up by lattice-work ; in Amphispyns
this intercalated network remains incomplete on the ventral and dorsal faces, whilst in
Tricolospyris it becomes complete, and in Perispyris spongy.

Subgenus 1. Amphispyrium, Haeckel.

Definition. — On each side of the ring-plane three pairs of large annular meshes ;
no middle zygomatic ring is developed between the two tympanic transverse rings
(superior orbital and inferior maxillary ring).

1 Amphispyris = Basket with a cap on both sides ; «,«?><, awy's.

1096 THE VOYAGE OF H.M.S. CHALLENGES.

1. Amphispyris thorax, n. sp. (PL 88, fig. 4).

Shell thorax-shaped, as long as broad, with a deep sternal incision and two slight transverse
strictures. On each side of the ring-plane three pairs of large, irregular, annular holes of nearly
equal size, the middle holes nearly half as broad as the shell. No zygomatic bars between the orbital
and maxillary bars. Lateral lattice-girdle narrow, with few small roundish meshes.

Dimensions. — Shell 017 long, 017 broad, ring 0'06 long.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

2. Amphispyris quadrigemina, n. sp. (PI. 88, fig. 6).

Shell shaped like the " corpora quadrigemina cerebralia," with two deep crossed strictures, a
coronal transverse stricture and a sagittal sternal stricture. On each side of the ring plane three
pairs of large, irregular, annular, double holes, the middle holes larger than the upper and lower
holes, and about one-fourth as long as the shell. No zygomatic bars between the orbital arid
maxillary bars. Lateral lattice-girdle broad, with numerous small meshes.

Dimensions. — Shell 013 long, 016 broad, ring 0'07 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Amphispyris reticulata, Haeckel.

Dictyospyris reticulata, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 289, Taf. x.
fig. 19.

Shell thorax-shaped, one and one-fifth times as long as broad, with a deep sternal incision and
two distinct transverse strictures. On each side of the ring-plane three pairs of large annular holes
of nearly equal size, about one-third as long as the shell. No zygomatic bars between the orbital and
maxillary bars. Lateral girdle narrow, with few large polygonal meshes.

Dimensions. — Shell 018 long, 015 broad.

Habitat. — Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).

Subgenus 2. Amphispyridium, Haeckel.

Definition. — On each side of the ring-plane four pairs of larger annular meshes ;
a middle horizontal zygomatic ring is developed between the two tympanic transverse
rings (superior orbital and inferior maxillary ring).

4. Amphispyris sternalis, n. sp. (PI. 88, fig. 2).

Shell thorax-shaped, one and one-fifth times as long as broad, with deep sternal incision and two
distinct transverse (tympanic) strictures. On each side of the ring-plane four pairs of large irregular,
annular holes ; the fourth (inferior or buccal) pair is the longest. The middle of the sagittal ring

REPORT ON THE RADIOLARIA. 1097

is crossed by horizontal zygomatic bars (between the ascending orbital and the descending maxillary
bars). Lateral lattice-girdle narrow, with few large meshes.

Dimensions. — Shell 0'24 long, 0'2 broad ; ring 0'09 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

5. Amphispyris subquadrata, n. sp. (PI. 88, fig. 5).

Shell compressed, nearly square, spiny, with slight sternal incision and two distinct transverse
strictures. Similar to the preceding species ; four pairs of irregular annular pores of nearly equal
size. Zygomatic ring complete. Lateral lattice-girdle narrow, with few large meshes.

Dimensions. — Shell 014 long, 012 broad ; ring 0'06 long.

Habitat. — Central Pacific, Station 285, depth 2275 fathoms.

6. Amphispyris costata, n. sp. (PI. 88, fig. 3).

Shell compressed, nearly square, with slight sternal incision and two obliterated transverse
strictures. Similar to the two preceding species ; with four pairs of large annular pores, the two
middle of which (the orbital and nasal holes) are much larger than the superior (frontal) and inferior
(oral) holes. Zygomatic ring incomplete. Lateral lattice-girdle broad, with very numerous, small,
irregular, polygonal pores.

Dimensions. — Shell 0'2 long, 016 broad ; ring 0'07 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

7. Amphispyris toxarium, n. sp. (PL 88, fig. 7).

Shell inflated, with deep sternal incision and two distinct transverse strictures. Similar to the
preceding species, but with deeper constriction and looser lattice-work. Four pairs of large, irregular,
annular pores, the central two of which are much larger. Zygomatic ring complete. Lateral girdle
broad, with irregular pores of very different size.

Dimensions. — Shell 0'2 long, 014 broad ; ring 0'09 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 482. Tricolospyris,1 Haeckel, 1881, Prodromus, p. 443.

Definition. — Androspyrida without free basal feet, with, three distinct joints,
separated by two transverse strictures ; lattice-work of the shell complete, simple.

The genus Tricolospyris has arisen from the preceding Amphispyris, its ancestral
form, by development of lattice-work which completely closes the large open holes
remaining on the ventral and dorsal faces of the latter.

1 Tricolospyris= Wicker-basket with three joints ; TJ<X«AOJ, o-ruj/f.

(ZOOL. CHALL. EXP.— PART XL. 1886.) Rr 138

1098 THE VOYAGE OF H.M.S. CHALLENGER.

1. Tricolospyris kantiana, n. sp. (PI. 88, fig. 10).

Shell smooth, one and a half times as long as broad, with two deep transverse strictures. Pores
of the cephalis large, roundish, of nearly equal size. Cupola and thorax hemispherical, of about the
same size and form, with numerous and small, double-contoured, roundish pores.

Dimensions. — Shell 012 long, 0'08 broad ; ring 0'04 long.

Habitat. — "Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Tricolospyris leibnitziana, n. sp. (PI. 88, fig. 9).

Shell spiny, twice as long as broad, with two deep transverse Strictures. Pores of the cephalis
large, roundish, polygonally framed, of very different size ; two middle transverse rows of smaller
pores enclosed between a superior and an inferior row of very large pores. Cupola and thorax
hemispherical, about equal, with much smaller and very numerous roundish pores.

Dimensions. — Shell 015 long, 0'07 broad ; ring 0'06 long.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

3. Tricolospyris baconiana, n. sp. (PI. 88, fig. 8).

Shell rough, twice as long as broad, with two sharp strictures. Pores of the cephalis large,
very irregular, partly lobated. Cupola hemispherical, smaller than the campanulate thorax, both
with smaller irregular pores.

Dimensions. — Shell 015 long, 0'08 broad ; ring 0'06 long.

Habitat. — Western Tropical Pacific, Station 215, depth 2500 fathoms.

4. Tricolospyris neivtoniana, n. sp. (PL 88, fig. 11).

Shell spiny, slender, three times as long as broad, with two distinct strictures. Pores of the
cephalis very large, irregular. Cupola hemispherical, only one-third as long as the slender
inversely conical abdomen, both with irregular, much smaller pores.

Dimensions. — Shell 0'22 long, 0-08 broad ; ring 0'05 long.

Habitat. — Western Tropical Pacific, Station 206, depth 2100 fathoms.

Genus 483. Perispyris,1 Haeckel, 1881, Prodromus, p. 444.

Definition. — An dro spy rid a without free basal feet, with three distinct joints,
separated by two transverse strictures ; lattice-work of the shell double or spongy.

The genus Perispyris differs from the preceding Tricolospyris, its ancestral form,
in the development of a secondary outer shell, which encloses the inner primary one
either like an enveloping cortical shell or like a spongy veil. This is produced by the
concrescence of meeting branches, which arise from spines of the inner shell.

1 Perispyris= Wicker-basket surrounded by an envelope ; ifi^

REPORT ON THE RADIOLARIA. 1099

1. Periapyrie bicincta, n. sp. (PL 88, fig. 13).

Shell smooth, with two deep transverse annular strictures and a deep sagittal incision at the
sternal base ; one and a half times as long as broad. Cephalis nut-shaped, with large irregular
roundish pores and very broad bars. Everywhere from its surface there arise numerous slender
arborescent radial beams; by the anastomoses of their ramified branches there arise the flat cap-
shaped cupola and the larger bilobed thorax ; and also the external enveloping shell with loose
delicate network.

Dimensions. — Inner shell 017 long, O'l broad ; outer shell 0'23 long, 017 broad ; ring 0'06 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Perispyris spongiosa, n. sp.

Shell rough, with two distinct transverse strictures and a deep sternal incision, similar to the
preceding ; the radial beams arising from the inner shell, and forming by anastomosing branches
the outer shell, are thinner and more numerous, and the framework of the latter on the surface is
very dense and spongy, therefore the shell is dark and not transparent.

Dimensions. — Inner shell 018 long, 012 broad ; outer shell 0'241ong, 018 broad ; ring 0'08 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Perispyris lentellipsis, n. sp. (PI 88, fig. 12).

Shell smooth, lentelliptical, with three different isopolar axes, perpendicular one to another.
Transverse and sagittal strictures are wanting ; but the large enclosed ring and the two pairs of
large adjacent annular meshes indicate clearly the position and size of the hidden cephalis. The
two other joints (the cupola on the upper and the thorax on the lower pole of the cephalis) are
nearly equal, cap-shaped or hemispherical. The outer lentelliptical shell is little larger than the
inner, connected with it by numerous thin bristle-shaped radial beams, and exhibits a delicate
arachnoidal lattice-work.

Dimensions. — Inner shell 015 long, 01 broad; outer shell 018 long, 013 broad; ring 0'08 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subfamily 3. NEPHKOSPYRIDA (vel PARADICTYIDA, Haeckel, 1881).

Definition. — Androspyrida without free basal feet and external constrictions.
Shell either spherical or discoidal.

Genus 484. Sphcerospyris,1 n. gen.

Definition. — Androspyrida with a spherical or subspherical shell, without
basal incision and transverse constriction ; without free basal feet.

1 Sphcerospyris = Spherical wicker-baaket ;

1100 THE VOYAGE OF H.M.S. CHALLENGEK.

The genus Sphcerospyris differs from all other Spyroidea in the regular spherical
or spheroidal form of the lattice-shell. It may therefore be easily confounded with some
species of the Sphseroidea; but the internal sagittal ring, placed in the median plane
of the fenestrated sphere and connected with it by radial beams, leaves no doubt that it
is derived from a true Spyroid, either Dictyospyris or Amphispyris, or another genus.
Sometimes also four larger collar pores are visible.

1. Sphcerospyris sphoera, Haeckel.

Dictyospyris sphcera, Biitechli, 1882, Zeitechr. f. wiss. Zool., vol. xxxvi. pp. 511, 539,
Taf. xxxii. fig. 15, a, b.

Shell smooth, nearly spherical, slightly flattened at the base, with small regular circular pores.
In the centre of the basal plate a regular rectangular cross with four equal collar pores.
Dimensions. — Diameter of the shell (HI, of the enclosed ring 0'06.
Habitat. — Fossil in Barbados.

2. Sphcerospyris quadriforis, n. sp.

Shell rough, nearly spherical, slightly flattened at the base, with small regular circular pores.
In the centre of the basal plate a bilateral symmetrical cross with four ovate collar pores ; two
cardinal pores twice as large as the two jugular pores and six to eight times as broad as the other
shell-pores.

Dimensions. — Diameter of the shell 0'26, of the enclosed ring 0'09.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

3. Sphcerospyris globosa, n. sp. (PL 83, fig. 4).

Shell smooth, perfectly spherical, with small subregular circular pores. In the centre of the
basal plate no larger collar pores. (The original collar pores are here of the same size as the other
pores, and cannot therefore be distinguished.)

Dimensions. — Diameter of the shell 0'13, of the enclosed ring 0'06.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 485. Nephrospyris,1 Haeckel, 1881, Prodromus, p. 444.

Definition — A ndrospyrida with a discoidal, kidney -shaped, or subcircular shell,
with a basal incision ; without transverse constriction and free basal feet.

The genus Nephrospyris is one of the most peculiar and most modified of the
Spyroidea, of extraordinary size, in this respect surpassing all other genera of this

1 Nephrospyris = Kidney-shaped basket ;

EEPOET ON THE KADIOLAEIA. 1101

suborder, and differing from them in its flat discoidal form. The diameter of the
compressed shell often reaches one half millimetre or more ; its perimeter is elliptical or
nearly circular, smooth, constantly with a characteristic deep sternal incision or a basal
sinus on the basal pole of the main axis. The central sagittal ring is comparatively
small. The margin is often inflated, like a delicate reticular girdle, and contains a large
number of peculiar spherical or roundish nucleated cells (PI. 90, figs. 6-10). Accord-
ing to the observations of Dr. John Murray, made on living Nephrospyris, they are
Vorticellina, perhaps constant Symbiontes.

Subgenus 1. Nephrodictyum, Haeckel, 1881, Prodromus, p. 444.
Definition. — Network of the shell simple, with bars of nearly equal breadth.

1. Nephrospyris renilla, n. sp. (PI. 90, figs. 9, 10).

Shell kidney-shaped, one and a half times as broad as long, and three tunes as long as the deep
kidney-shaped sternal incision. Ring with six pairs of branched apophyses, the bars of the
apical pair vertical, of the basal pair divergent. The corresponding bars of the two middle pairs
(on the frontal and the occipital face) form together on each side a large pentagonal or hexagonal
naso-orbital area, which is surrounded by four or five large polygonal meshes ; the other meshes
become smaller towards the inflated margin. All meshes simple, without arachnoidal framework.

Dimensions. — Shell 0'3 to 0'4 long, 0'4 to 0'5 broad ; ring 0'08 to 01 long.

Habitat.-^- Central Pacific, Station 272, depth 2600 fathoms.

2. Nephrospyris nephridium, n. sp.

Shell kidney-shaped, one and two-third times as broad as long, very similar to the preceding species
(or only a variety of it ?). Ring with seven pairs of branched apophyses. The large naso-orbital
area is on the dorsal or occipital side simple, on the ventral or facial side divided by an equatorial
pair of transverse horizontal branches into two superior orbital, and two inferior nasal holes.
Sternal incision ovate. All meshes simple.

Dimensions — Shell 0'25 to 0'35 long, 04 to 0'5 broad ; ring 0'07 to 0'08 long.

Habited. — Central Pacific, Station 274, depth 2750 fathoms.

3. Nephrospyris phaseolus, n. sp.

Shell kidney-shaped, twice as broad as long, very similar to the two preceding species (or only
a variety of them ?). Ring with eight pairs of branched apophyses. The large naso-orbital area
(between the mitral and collar ring) is on the dorsal and on the ventral side divided by two
equatorial pairs of horizontal branches into two superior (orbital and occipital), and two inferior
(nasal and suboccipital) holes. Sternal incision cordate. All meshes simple.

Dimensions. — Shell 0'25 long, 0'5 broad ; ring 0'06 to 0'07 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

1102 THE VOYAGE OF H.M.S. CHALLENGER.

4. Nephrospyris cordata, n. sp.

Shell heart-shaped, about as long as broad. Ring with six pairs of branched apophyses (as in
Nephrospyris renilla, PI. 90> fig. 9). No equatorial transverse branches. Sternal incision cordate,
deeper than in all other species of the genus, nearly half as long as the shell. All meshes of
the network simple.

Dimensions. — Shell 0'32 long, 0'36 broad ; ring 0'05 to 0'06 long.

Habitat.— Central Pacific, Station 263, depth 2650 fathoms.

Subgenus 2. Paradictyum, Haeckel, 1881, Prodromus, p. 444.

Definition. — Network of the shell double ; the larger meshes separated by strong
bars, and filled up by a very delicate secondary arachnoidal network.

5. Nephrospyris paradictyum, n. sp. (PI. 90, figs. 1-8).

Paradietyum paradoxum, Haeckel, 1881, Prodromus et Atlas, loc. cit.

Shell nearly circular, ten times as broad as the inflated marginal girdle, and three times as long
as the sternal incision. Ring with six pairs of branched apophyses ; the bars of the apical pair
nearly vertical, of the basal pair divergent ; the corresponding and opposite bars of the two middle
pairs (on the occipital and on the frontal face) form together a large middle naso-orbital area ; above
and below this lie six pairs of larger meshes. All larger meshes of the network are filled up by
very delicate arachnoidal framework. The inflated and delicately reticulated marginal girdle of
this and of the following closely allied species is usually filled up by nucleated roundish cells
(fig. 7), which are Vorticellinse, according to the observations of Dr. John Murray on living
specimens.

Dimensions. — Diameter of the shell O5 to 0'6, of the marginal girdle 0'05 to 007 ; ring 0'07
to 0-09 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

6. Nephrospyris paradoxa, n. sp.

Shell kidney-shaped, one and one-third tunes as broad as long, six times as broad as the inflated
marginal girdle, and half as long as the sternal incision. Ring with six pairs of apophyses. Above
and below the large naso-orbital holes lie ten pairs of larger meshes. All the meshes are filled up
by very delicate arachnoidal network.

Dimensions. — Length of the shell 0'4 to 0'5, breadth 0'5 to 0'7 ; ring 0'06 to 0'08 long.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

REPORT ON THE RADIOLARIA. 1103

Suborder II. BOTRYODEA, Haeckel, 1881 (PI. 96).

Polycyrtida, Haeckel, 1862, Monogr. d. Radiol., p. 341.
Polycyrtida, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 519.
Botryodea ( = Botrida vel Botryida), Haeckel, 1881, Prodromus, p. 439.

Definition. — NASSELLARIA with a complete lattice-shell, exhibiting constantly a
lobate and multilocular cephalis, with three to five or more separated lobes, and two
to three or more constrictions.

The suborder Botryodea differs from the other Cyrtellaria in the multi-
locular and lobate shape of the cephalis, which is composed of at least three or four, often
five or six, and sometimes even a greater number of lobes, which are separated by con-
strictions and partly also by internal septa. This characteristic shape is found neither
in the Spyroidea (with bilocular cephalis) nor in the Cyrtoidea (with simple
cephalis). The affinities of the former group to the two latter form a very complicated
problem, which is not yet solved ; the morphology of the Botryodea is the most
difficult part in the system of NASSELLARIA, and what we can here give, are incomplete
and unsatisfactory beginnings only.

Up to the year 1860 only a single genus of the Botryodea was known, Litho-
botrys, one of the oldest genera of " Polycystina," and described by Ehrenberg
in 1844 (Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 74). He gave the
following definition : — " Loricse silicese articuli in adulto non in seriem, sed in uvse
brevis formam, id est in loculos plus minus discretes nonnullos contiguos dispositi.
Proxime ad Lithocampem accedit." In his first System (1847) Lithobotrys is placed
with Lithocampe among his family Lithochytrina. Afterwards (1860) Ehrenberg added
two new genera, under the names Botryocampe and Botryocyrtis and figured some
species of these incompletely in his last works (1872, 1875).

In my Monograph I founded for these three genera the separate subfamily of Poly-
cyrtida, added as a fourth genus Spyridobotrys, and gave to the group the following
definition (1862, loc. cit., p. 341): — "Lattice-shell divided by two or more annular
strictures, partly longitudinally, partly transversely, into three or more unequal
chambers, which are placed in different planes and have a different relation to the poles
of the shell-axis."

The new and remarkable forms of Botryodea, which I subsequently found in
the Challenger collection, demonstrated that the Botryodea differ from the other
Cyrtellaria (the Cyrtoidea as well as the S p y r o i d e a) in a far higher
degree than" I formerly had supposed. A synopsis of the figures in PI. 96 will give
sufficient evidence of this view. Therefore in my Prodromus (1881, p. 439)

1104 THE VOYAGE OF H.M.S. CHALLENGER.

I completely separated the Botryodea (or Botrida) from the other suborders of
Cyrtellaria (Spyrida and Cyrtida).

Biitschli gave, in 1882, in his paper on the Cyrtida (loc. cit.)avery accurate descrip-
tion of Lithobotrys geminata, and pointed out its close affinity to Lithocorythium and
Lithomelissa, and the importance of an oblique septum separating the cephalis into a
smaller anterior and a larger posterior lobe. His views on the Botryodea (as a
subordinate group of the Cyrtoidea) are however incomplete, since the peculiar
forms, described in the following pages, were unknown to him.

According to the wide morphological divergence of the different Botryodea, and
the numerous peculiar forms developed from it, we here divide the whole group into
three families and ten genera, with fifty -five species. These form, however, only a small
part of the large and varied mass of closely related forms which are found in the rich
collections of the Challenger. The great difficulty of researches on their intimate
structure, and the great amount of time required for it, prevented me from giving a
more complete and exact description than the one here given. The observation of the
small shells from all the different sides is a difficult task, requiring years of work, and its
satisfactory explanation would be possible only by means of numerous figures.

The three families of Botryodea, here described, correspond to the three first
groups of Cyrtoidea. The first family, Cannobotryida, corresponds to the Mono-
cyrtida clausa and to the Zygospyrida ; their shell consists of a cephalis only, without
subsequent joints. The second family, Lithobotryida, corresponds to the Dicyrtida and
Phormospyrida ; their shell is composed of a cephalis and a thorax, both joints being
separated by a transverse cortinar septum and a collar stricture. The third family,
Pylobotryida, has a three-jointed shell, like the Tricyrtida, with cephalis, thorax and
abdomen.

The cephalis is the most characteristic part of the shell of the Botryodea and
its lobulate and multilocular shape separates them from the Spyroidea and C y r-
toidea. It represents the whole shell in the Cannobotryida, and in the young
state of the two other families, which afterwards develop a thorax (Lithobotryida) and
an abdomen (Pylobotryida). The typical lobulation of the cephalis is probably
originally caused by internal septa ; and these may be originated by branches of the
internal columella, which corresponds either to the central ascending columella of the
Plectoidea or to the excentric ascending dorsal rod of the sagittal ring of the
Stephoidea. But afterwards, when the original septa disappear and are lost by
reduction, only the external constrictions remain to indicate the limits of the single
lobes.

Among the internal septa and the corresponding external constrictions which effect
the lobulation of the cephalis, may be distinguished primary or constant septa and
secondary or inconstant septa. As primary septa we regard firstly an oblique frontal

EEPORT ON THE RADIOLARIA. 1105

septum and secondly a vertical sagittal septum. The frontal septum (described
accurately by Biitschli) has usually two or three pairs of pores and ascends obliquely
from the base to the anterior face of the cephalis, where it is inserted in the orbital
region ; it divides the cephalis into a smaller anterior or facial lobe and a larger
posterior or occipital lobe. The latter is commonly higher and more developed than
the former and partly covers its upper face, like the crest of a helmet. The facial lobe
is again bisected by an incomplete sagittal septum and a corresponding partial
constriction on the anterior face. We find, therefore, in this original cephalis of the
Botryodea, three primary lobes, an odd larger occipital lobe and two paired smaller
facial lobes. The typical trilobed cephalis may be regarded perhaps as the common
original form of the Botryodea.

The secondary and inconstant constrictions which we find in many Botryodea,
and which produce a greater number of lobes in the cephalis, require further accurate
observation. The following cases of lobation may be considered as the most im-
portant : — (l) Cephalis with four lobes, opposite in two pairs (two larger occipital
and two smaller facial lobes, separated by a complete sagittal and an oblique frontal
constriction) ; (2) cephalis with four unequal lobes, two of which are odd and sagittal,
two paired and lateral (the odd occipital lobe usually larger and the odd mandibular
lobe smaller than the two paired lateral or buccal lobes) ; (3) cephalis with five lobes
(a large odd occipital lobe and two pairs of smaller lobes, anterior nasal, and lateral
buccal lobes) ; (4) cephalis with five lobes, three of which are odd (a posterior occipital,
middle frontal, and anterior facial lobe), and one pair of lateral lobes ; (5) cephalis with
six lobes, opposite in pairs (two larger occipital, two smaller nasal and two intermediate
lateral or buccal lobes); (6) cephalis with six lobes, two of which are odd and sagittal
(a large occipital and a smaller nasal lobe), four opposite in pairs (two anterior and two
posterior buccal lobes) ; (7) cephalis with seven lobes, three of which are odd (a large
posterior occipital, a middle frontal, and an anterior small nasal lobe), four opposite in
two pairs (an anterior buccal and a posterior temporal pair) ; (8) cephalis with eight
lobes, two of which are odd (a large posterior occipital and a small anterior frontal lobe)
and six opposite in three lateral pairs ; (9) cephalis with nine lobes, three of which are
odd (an occipital, a frontal and a nasal lobe) and six opposite in three lateral pairs ;
(10) cephalis with ten lobes, two of which are odd (a large occipital and a smaller
frontal lobe) and the other eight opposite in pairs ; (11) cephalis with numerous lobes
(twelve to fifteen or more) which are symmetrically disposed on each side of the
median plane ; (12) cephalis with numerous lobes (twelve to fifteen or more) which are
irregularly and sometimes spirally conglomerated.

All these different forms of lobation require a far more thorough examination than
I can devote to them, and may furnish examples of regular laws of development. The
irregular forms are rather common, and I have found some very irregular Botryodea

(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 139

1106 THE VOYAGE OF H.M.S. CHALLENGER.

(not here described) in which I could not determine the topographical regions of the
cephalis. The difficulty in the examination of these complicated forms is increased by
their very small size, which does not reach the usual dimensions of the other C y r t e 1-
1 a r i a. In some cases I was able to observe on the base of the cephalis the same typical
cortiiiar pores (in two or three pairs), which we also find in the same part of the cephalis
in the Spyroidea and Cyrtoidea, and which are inherited from the Semantida.

The thorax of the Botryodea, or the second shell -joint, absent in the
Cannobotryida, is usually of very simple form, ovate, truncate, conical or cylindrical,
and consists of a secondary joint, developed from the base of the cephalis. The
thorax is usually small, about the same size as the cephalis or a little larger, whilst in
the Cyrtoidea it is commonly much larger than the latter. Its terminal mouth is
closed by a lattice-plate in the Botryocellida, while it remains open in the Botryopylida
and Pylobotryida.

The abdomen, or the third shell-joint, developed in the Pylobotryida only, generally
also exhibits a very simple shape, like the thorax, and it is a tertiary joint developed
from the base of the thorax. It exhibits to the latter the same relation as in the
Tricyrtida. The terminal mouth of the abdomen remains open in the Botryocyrtida ;
it becomes closed by a lattice-plate in the Botryocampida.

The lattice-plate forming the shell of the Botryodea is usually very thin and
fragile, with very small circular pores. These are often very numerous, at other
times scarce, and sometimes nearly wanting, so that the shell appears hyaline. In this
group there never occurs that great variety in form and size of the pores, which
numerous Cyrtoidea and Spyroidea exhibit..

The radial apophyses which are found in the majority of Botryodea seem to
correspond in position and relation to the typical radial beams of the other NASSELLARIA,
viz., three descending basal feet arising from the base of the cephalis, and an ascending
vertical apical horn arising from the top of the cephalis. Here also they seem to be
inherited from the Plectoidea or Stephoidea ( Cortina, Cortiniscus). But
whilst these four typical radial beams in the other NASSELLARIA are usually simple
spines or solid rods, here they usually appear as hollow cylindrical tubes, the thin wall
of which is pierced by the same small pores as the shell. These porous tubes are either
straight or slightly curved, often inflated and ovate at the base. We find in their
number and disposition the same variety as in the simple radial spines of the other
NASSELLARIA. The original number may here also be seen in the development of four
typical beams, an ascending apical tube on the top of the cephalis, and three descending
basal tubes on its base ; the odd posterior tube of the latter corresponds to the caudal
foot, the two paired anterior to the pectoral feet. There is often also a fourth foot
developed opposite to the caudal, and representing a sternal tube. Sometimes also two
superior tubes are developed, a posterior occipital and an anterior frontal. The different

REPORT ON THE RADIOLARIA. 1107

apophyses may be lost by reduction. I have never observed Botryodea with more
than five apophyses.

TJie Central Capsule of the Botryodea is not yet sufficiently known, no living
species having been observed. In some preparations from specimens in the Challenger
collections, stained by Dr. John Murray with carmine immediately after the dredging
operation, single Botryodea are to be found in which the central capsule is deeply
coloured. In Botryopera quinqueloba (PI. 96, fig. 2) it filled up the greater part
of the cephalis and seemed to be divided into some small lobes. In Lithobotrys
sphcerothorax (PI. 96, fig. 15) it was divided into four lobes, three of which filled
the trilobed cephalis, the fourth large lobe occupying a great part of the spherical
thorax. Details of their structure, unfortunately, were not recognisable. There can,
however, be no doubt that they are the same as in all other NASSELLARIA.

Synopsis of • the Families of Botryodea.

1. Shell monothalamous, consisting of the lobate cephalis only, . . .1. CANNOBOTRYIDA.

2. Shell dithalamous, composed of a lobate cephalis and a simple thorax, . . 2. LITHOBOTRYIDA.

3. Shell trithalamous, composed of a lobate cephalis, a thorax and an abdomen, . 3. PYLOBOTRYIDA.

Family LVI. CANNOBOTEYIDA, Haeckel (sensu emendato).

Cannobotryida, Haeckel, 1881, Prodromus, p. 440.

Definition. — Botryodea monothalamia, the shell of which represents a lobate cephalis,
without thorax and abdomen.

The family Cannobotryida (retained here with a stricter definition than originally
was given in my Prodromus) comprises those Botryodea, in which the whole shell is
represented by the cephalis alone, without thorax and abdomen. Since the two latter
joints, found in the two following families, are secondary productions, the Cannobotryida
must be regarded as the ancestral forms of all Botryodea, in an ontogenetic as well
as in a phylogenetic sense.

Two species only of this family have been hitherto known, incompletely described
by Ehrenberg as Lithobotrys triloba and Lithobotrys quadriloba. A great number of
similar forms are to be found in the Radiolarian ooze of the Central Pacific, but they
are very minute, and difficult to examine. We can describe here only twelve species
of these, which we arrange in two genera ; Botryopera without porous tubes, and
Cannobotrys bearing a variable number of porous cylindrical tubes (one to five). The
number of lobes of the cephalis is also variable in each genus (one to five or more). If
in the future these minute and interesting shells should be better examined, it would

1108 THE VOYAGE OF H.M.S. CHALLENGER.

be advisable to distinguish a number of genera according to the different number of the
porous tubes and of the lobes of the cephalis. The base of the latter is constantly
closed by a basal lattice-plate, and usually exhibits two or three pairs of cortinar pores,
identical with those of the Semantida,

The phylogenetic origin of the Cannobotryida may be found either in the
Zygospyrida or in the Monocyrtida ; they differ from these two similar groups in the
lobation of the cephalis, which is effected by the development of internal septa and
external constrictions.

Synopsis of the Genera of Cannobotryida.
Cephalis without porous tubes, ....... 486. Botryopera.

Cephalis with a variable number of porous tubes, ..... 487. Cannobotrys.

Genus 486. Botryopera? n. gen.
Definition. — C annobotryida without tubes on the cephalis.

The genus Botryopera is the simplest form among the Botryodea, the shell con-
sisting of a lobate cephalis only, without tubes or radial appendages. It may be derived
either from Dictyospyris or from Archicapsa by development of the horizontal fold in the
frontal face of the shell, and the corresponding internal frontal septum, which separates the
larger occipital lobe from the smaller facial half ; the latter may be divided again into
paired frontal lobes, lateral buecal lobes, &c. Botryopera may be the common ancestral
form of many Botryodea.

1. Botryopera cyrtoloba, n. sp. (PL 96, fig. 1).

Cephalis trilobate ; the posterior odd occipital lobe helmet-shaped, about twice as large as the
two paired anterior frontal lobes, which are subovate and covered by the upper half of the former.
Pores small and numerous, subregular, circular ; some larger pores at the base.

Dimensions. — Length of the shell 0'08, basal breadth 0'06.

Habitat. — Central Pacific, Station 265 to 274, depth 2350 to 2925 fathoms.

2. Botryopera triloba, Haeckel.

Lithobotrys triloba, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 30.

Cephalis trilobate ; the occipital lobe subcylindrical, one and a half times as long as the two
frontal lobes, which are slender, ovate and not covered by the former. Pores small and numerous.
Dimensions. — Length of the shell O'Oo, breadth 0'03.

Habitat. — Fossil in Tertiary rocks of the Mediterranean (Sicily, Greece, &c.)

1 Botryopera = Basket with grapes ; /3»rjt/s, -a^a..

REPORT ON THE RADIOLARIA. 1109

3. Botryopera quadriloba, Haeckel.

Lithobotrys quadriloba, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 84.

Cephalis quadrilobate ; the occipital lobe helmet-shaped, one and a half times as long as the two
paired hemispherical buccal lobes, and twice as large as the anterior frontal lobe. Pores not
numerous, rather large, circular.

Dimensicms. — Length of the shell 0'06, breadth 0'04.

Habitat. — Fossil in Barbados and North America (Virginia).

4. Botryopera quinqueloba, n. sp. (PL 96, fig^ 2).

Cephalis quinquelobate ; the occipital lobe helmet-shaped, and twice as long as the two hemi-
spherical frontal lobes, three times as long as the subspherical lateral buccal' lobes. Pores scarce,
small, circular.

Dimensions. — Length of the shell 0'07, basal breadth 0'05;.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

5. Botryopera multiloba, n. sp.

Cephalis multilobate ; the posterior odd occipital lobe ovate, and of about the same size as the
anterior frontal half of the shell, which is clustered and divided into five to seven smaller lobes, an odd
subspherical sternal lobe, and on each side of it two or three pairs of smaller subspherical lobes.

Dimensions. — Length of the shell 0'09, breadth 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Genus 487. Cannobotrys,1 Haeckel, 1881, Prodromus, p. 440.
Definition. — C annobotryida with tubes on the cephalis.

The genus Cannobotrys differs from the preceding Botryopera in the development
of hollow radial tubes, arising from the lobate cephalis in various numbers. According
to their number the genus may be divided into various subgenera : (1) Cannobotrantha
(monocanna) with a single apical tube ; (2) Cannobotrella (dicanna) with two divergent
tubes, an ascending apical and a descending sternal one ; (3) Cannobotrissa (tricanna)
with three tubes in the sagittal plane (an upper apical, a posterior caudal, and an
anterior sternal) ; (4) Cannobotromma (tetracanna) with four radial tubes disposed like
the four typical spines of Cortina (compare p. 950), and Cannobotrusa (pentacannd)
with five radial tubes disposed like the five typical spines of Stephanium (p. 952).

1 Cannobotrys= Grape with tubes; xauna,

1110 THE VOYAGE OF H.M.S. CHALLENGER.

Perhaps these five groups may be separated as five genera, possessing near relations to
five very different genera of NASSELLARIA (Circospyris, Halicapsa, Archibursa, Cortina,
Stephanium, &c.

1. CoMnobotrys monocanna, n. sp.

Cephalis trilobate, with a single cylindrical straight apical tube on the apex of the occipital
lobe, which is helmet-shaped, and about one and a half times as long as the two subspherical
frontal lobes. Pores small and numerous, subregular, circular.

Dimensions. — Length of the shell 0'05, breadth 0'03.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Cannobotrys dicanna, n. sp.

Cephalis quadrilobate, with two divergent tubes, an odd apical tube on the apex of the posterior
occipital lobe, and an odd sternal tube on the anterior frontal lobe. Between these two odd lobes
lie two paired lateral or buccal lobes, of about the same size. Shell nearly hyaline, with very
few minute pores.

Dimensions. — Length of the shell 0'06, breadth 0'04.

Habitat. — Indian Ocean ; Madagascar (Rabbe), surface.

3. Cannobotrys tricanna, n. sp. (PI. 96, fig. 3).

Cephalis quinquelobate, with three curved cylindrical tubes in the sagittal plane ; an ascending
apical tube on the apex of the helmet-shaped occipital lobe, and two horizontal tubes on the base of
the shell (a posterior caudal, c, and an anterior sternal, 2). The two frontal lobes are hemispherical,
and twice as large as the two lateral buccal lobes. Pores very small and numerous.

Dimensions. — Length of the shell 0'08, basal breadth 0'06.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Cannobotrys sagittalis, n. sp.

Cephalis multilobate, with three straight divergent cylindrical tubes in the sagittal plane ; a
vertical apical tube on the apex of the ovate occipital lobe, and two horizontal tubes on the base, as
in the preceding similar species ; it differs from the latter in the greater number of lobes (seven or
nine), the two frontal lobes being divided into two or four secondary lobules.

Dimensions. — Length of the shell 01, breadth 0'07.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

5. Cannobotrys cortina, n. sp. (PI. 96, fig. 4).

Cephalis quinquelobate, with four cylindrical nearly straight tubes of equal size ; an ascending,
nearly vertical, apical tube on the apex of the occipital lobe, and three divergent descending tubes

REPORT ON THE RADIOLARIA. 1111

on the base of the shell (an odd posterior caudal tube and two paired anterior pectoral tubes). The
two lateral buccal lobes are twice as large as the two anterior frontal lobes, and half as large as the
posterior odd occipital lobe. The four tubes in this and the following species correspond probably
to the four spines of Cortina (p. 950).

Dimensions. — Length of the shell 0'07, basal breadth 0'06.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

\

6. Cannobotrys tetracanna, n. sp.

Cephalis multilobate, with four cylindrical curved tubes conical at their wider base, correspond-
ing to those of the preceding species and to the four spines of Cortina. The odd occipital lobe is
of about the same size as the anterior part of the shell, which is cleft into three pairs of roundish
lobes, one pair ofAnterior larger frontal lobes, and two pairs of smaller lateral buccal lobes. Pores
very few and minute.

Dimensions. — Length of the shell O'll, basal breadth 0'07.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

7. Cannobotrys pentacanna, n. sp.

Cephalis quinquelobate, with five cylindrical slender curved tubes, three of which are placed in
the sagittal plane (a superior apical, a posterior caudal, and an anterior sternal), whilst the other
two are paired and diverge laterally (two pectoral tubes). The five tubes correspond exactly to
the five typical spines of Stephanium (p. 952). The helmet-shaped occipital lobe of the shell is
twice as large as each of the two anterior frontal lobes, and three times as large as each of the two
lateral buccal lobes. Pores numerous.

Dimensions. — Length of the shell 0'07, basal breadth 0'04.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Family LVII. LITHOBOTRYIDA, n. fam.

Definition. — Botryodea dithalamia, the shell of which is composed of a lobate
cephalis and a simple thorax, without abdomen.

The family Lithobotryida comprises those Botryodea in which the shell is
divided by a transverse annular constriction into a lobate cephalis and a simple thorax.
They correspond therefore to- the Dicyrtida among .the Cyrtoidea, and to the
Phormospyrida among the Spyroidea. The thorax, or the second shell -joint, is in
all these three families a secondary production, arising from the base of the cephalis ;
therefore the Lithobotryida must be phylogenetically derived from the Cannobotryida.

Several species of Lithobotrys were first described by Ehrenberg as Lithobotrys
and Lithocorythium. These two genera are, however, identical, as has been

1112 THE VOYAGE OF H.M.S. CHALLENGER.

demonstrated by Biitschli (1882, loc. cit., p. 519). Some other species united by
Ehrenberg with Lithobotrys belong to other genera. The number of Lithobotryida
found in the " Eadiolarian ooze " of the Challenger collection, is far greater than that of
the Cannobotryida and Pylobotryida. But only a small part of them could be
thoroughly examined and described here, so that their number may be greatly
augmented by further accurate researches. We here arrange those forms in four
genera, representing two different subfamilies. The terminal mouth of the thorax
remains open in the Botryopylida, whilst it becomes closed by a lattice-plate in the
Botryocellida. In each group there are shells with and without porous tubes. The
number of these tubes, and also the number of lobes of the cephalis, is very variable,
and may in future serve for the distinction of more genera.

Synopsis of the Genera of Lithobotryida.

I, Subfamily ( Cephalis without porous tubes, .... 488. Botryopyle.

Botryopylida.
Mouth of the thorax open. ( Cephalis with a variable number of porous tubes, . 489. Acrobotrys.

II. Subfamily

Botryocellida.

Mouth of the thorax closed
by a lattice-plate.

Cephalis without porous tubes, .... 490. Botryocella.
Cephalis with a variable number of porous tubes, . . 491. Lithobotrys.

Genus 488. Botryopyle, Haeckel, 1881, Prodromus, p. 440.

Definition. — L ithobotryida without tubes on the cephalis, and with the
mouth of the thorax open.

The genus Botryopyle comprises the simplest forms of Lithobotryida, the lobate
cephalis bearing no tubes and the basal mouth of the thorax remaining open. It may
be derived either from Dictyocephalus or from Desmospyris, by development of lobes
on the cephalis and of an internal frontal septum, separating the larger occipital lobe from
the smaller frontal half of the shell. The latter may be divided again into anterior
frontal lobes, lateral buccal lobes, &c.

1. Botryopyle sethocorys, n. sp. (PI. 96, fig. 7).

Cephalis trilobate, separated by a deep collar constriction from the hemispherical thorax, which is
twice as broad. Occipital lobe helmet-shaped, little longer than the two hemispherical frontal lobes.
Surface spiny. Pores irregular, roundish, of very different size.

Dimensions. — Length of the shell O'l, breadth 0'07.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

REPORT ON THE RADIOLARIA. 1113

2. Botryopyle cribrosa, Haeckel.

Lithobotrys cribrosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iii.

fig. 20.

? Lithobotrys biceps, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 295, Taf. ix.
fig. 23.

Cephalis trilobate, separated by a slight collar constriction from the ovate thorax, which is
somewhat smaller. Occipital lobe very large, helmet-shaped, longer than the thorax and twice as
long as the two subspherical frontal lobes. Pores regular, circular, scarce.

Dimensions. — -Length of the shell Oil, breadth 0'05.

Habitat. — Fossil in Barbados.

3. Botryopyle cephalodes, Haeckel.

Lithocorythiwn cephalodes, Ehrenberg, 1875, Abhandl. d, k. Akad. d. Wiss. Berlin, p. 78,
Taf. iv. fig. 6.

Cephalis quinquelobate, separated by a slight collar constriction from the larger conical
thorax, which is gradually dilated towards the wide mouth. Occipital lobe helmet-shaped, little
longer than the frontal half of the cephalis, which is divided into two pairs of lateral chambers,
corresponding to the four crossed pores of the sagittal septum, figured by Ehrenberg. The figure
of the latter is inverse, seen from the frontal face, a part of the frontal wall having been broken off.

Dimensions. — Length of the shell 0-08, breadth 0'05.

Habitat. — Fossil in Barbados.

4. Botryopyle dictyocephalus, n. sp. (PL 96, fig. 6).

Cephalis multilobate, separated by an oblique constriction from the subcylindrical thorax,
which is somewhat larger and slightly curved. Occipital lobe conical, of the same length as the
posterior part of the triangular frontal half of the shell, which is divided into five to seven
lobes, two or three odd lobes in the median part, and one or two pairs of lateral lobes; very
variable in size and form of the lobes. Mouth of the thorax wide, truncate.

Dimensions. — Length of the shell 012, breadth 0'07.

Habitat. — Central Pacific, Station 271 to 274, depth 2350 to 2750 fathoms.

5. Botryopyle inclusa, n. sp. (PI. 96, fig. 5).

Cephalis multilobate, campanulate, separated by a sharp constriction from the inflated thorax,
which is nearly twice as long and broad. Both joints of the shell are irregularly lobate, with
numerous vaulted lobes of different sizes, and partly internal septa. Pores small and numerous.

Dimensions. — Length of the shell 01, breadth 0'06.

Habitat. — Mediterranean (Candia) Spratt, depth 1620 fathoms.

(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 140

1114 THE VOYAGE OF H.M.S. CHALLENGEE.

Genus 489. Acrobotrys, Haeckel,1 1881, Prodromus, p. 440.

Definition. — L ithobotryida with tubes on the cephalis, and with the mouth
of the thorax open.

The genus Acrobotrys differs from the preceding Botryopyle in the development
of radial tubes, and from its probable ancestral form, Cannobotrys, in the development
of a thorax, the basal mouth of which remains open. According to the varying
number of the tubes we may distinguish the following five subgenera (corresponding to
those of Cannobotrys], viz., (l) Acrobotrantha (monosolenia) with a single (apical)
tube ; (2) Acrobotrella (disolenia) with two divergent tubes (an apical and a sternal) ;
(3) Acrobotrissa (trisolenia) with three sagittal tubes (an apical, a caudal, and a
sternal) ; (4) Acrobotromma (tetrasolenia) with four tubes, like the four typical spines
of Cortina ; and (5) Acrobotrusa (pentasolenia) with five feet, corresponding to the
five typical spines of Stephanium.

1. Acrobotrys monosolenia, n. sp.

Cephalis trilobate, with a single straight apical tube, which ascends vertically from the apex
of the occipital lobe, and is pointed at the distal end, with an anterior oblique aperture. Two
frontal lobes paired, ovate, half as long as the helmet-shaped occipital lobe. Thorax ovate, twice
as long as the cephalis. Pores very scarce.

Dimensions. — Length of the shell 0'08, breadth 0'06.

Habitat. — Mediterranean (Corfu), surface.

2. Acrobotrys disolenia, n. sp. (PI. 96, fig. 10).

Cephalis trilobate, with three odd ovate lobes of nearly equal size in the sagittal plane and
two divergent straight slender cylindrical tubes, a vertical apical tube on the occipital lobe, and a
horizontal nasal tube on the frontal lobe ; the middle lobe between them is somewhat smaller.
Thorax ovate, about twice as large as the cephalis, with constricted mouth. Pores small and
numerous.

Dimensions. — Length of the shell 01, breadth 0'06.

Habitat. — Central Pacific, Station 265 to 274, depth 2350 to 2925 fathoms.

3. Acrobotrys aquaria, n. sp.

Cephalis quinquelobate, with two divergent long cylindrical curved tubes. Occipital lobe
helmet-shaped, with an ascending apical tube ; nasal lobe conical, with a descending sternal tube ;

1 Acrobotrys= Perfect grape ; **;<>'?,

REPORT ON THE RADIOLARIA. 1115

between them a smaller odd middle lobe, and on each side of the latter an ovate frontal lobe.
Thorax inflate, twice as long and broad as the cephalis. Pores small, scarce.

Dimensions. — Length of the shell 0'09, breadth O07.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

4. Acrobotrys acuminata, n. sp. (PL 96, fig. 9).

Cephalis sexlobate, with two divergent tubes. Occipital and frontal lobes ovate, odd ; between
them a cupola-shaped apical lobe, bearing an ascending pointed apical tube. On each side at the
base a small buccal lobe, and between the paired buccal lobes an anterior nasal lobe with a descend-
ing curved sternal tube. Thorax smaller than the cephalis. Pores numerous and small

Dimensions. — Length of the shell O'll, breadth 0'09.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Acrobotrys auriculata, n. sp. (PI. 96, fig. 11).

Cephalis quadrilobate, with three pointed and auriculate tubes, two ascending apical (an
anterior and a posterior) in the helmet-shaped occipital lobe, and a descending sternal tube on the
base of the frontal lobe ; between the lobes two lateral paired buccal lobes. Thorax campanulate,
twice as broad as the cephalis. Pores rather large and numerous.

Dimensions. — Length of the shell O'l, breadth 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

6. Acrobotrys trisolenia, n. sp. (PL 96, fig. 8).

Cephalis quadrilobate, with four odd lobes and three divergent curved tubes, an ascending apical
tube in the conical occipital lobe, and two descending tubes on the anterior and posterior basal
lobes ; between these three lobes a small central lobe. Thorax ovate, about as large as the cephalis.
Pores small and numerous.

Dimensions. — Length of the shell O'll, breadth 0'05.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

7. Acrobotrys tetrasolenia, n. sp.

Cephalis trilobate, with four slender cylindrical tubes. Occcipital lobe helmet-shaped, with an
apical tube on the apex and a caudal tube on the base. Two frontal lobes ovate, prolonged into
two paired pectoral tubes. The four tubes correspond in position to the four spines of Cortina.
Thorax inflate, ovate, larger than the cephalis. Pores very scarce, rather large, irregular.

Dimensions. — Length of the shell 0'08, breadth 0'05.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

8. Acrobotrys pentasolenia, n. sp.

Cephalis quinquelobate, with five short conical tubes ; three divergent odd tubes arise from three
odd lobes; an apical from the occipital lobe, a posterior caudal from the suboccipital lobe, and an

1116 THE VOYAGE OF H.M.S. CHALLENGER.

anterior sternal from the nasal lobe. Two paired lateral tubes arise from the base of two ovate
frontal lobes. The five tubes correspond in disposition to the five spines of Stephanium. Thorax
truncate. Pores small.

Dimensions. — Length of the shell 012, breadth 0'09.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 490. Botryocella,1 Haeckel, 1881, Prodromus, p. 440.

Definition. — L ithobotryida without tubes on the cephalis, and with the mouth
of the thorax closed.

The genus Botryocella differs from the closely allied Botryopyle in having the mouth
of the thorax closed, and may be derived from it by development of a lattice-plate,
effecting this closure. It bears therefore the same relation to the latter that Dicolocapsa
has to Dictyocephalus.

1. Botryocella nucula, Haeckel.

Lithobotrys nucula, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iii.

fig. 16.
Lithobotrys adspersa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iii.

fig. 15.

Cephalis trilobate ; occipital lobe helmet-shaped, nearly twice as long as the two ovate frontal
lobes. Thorax about as long as the cephalis. Pores very small and scarce.
Dimensions. — Length of the shell 0'06, breadth 0'03.
Habitat. — Fossil in Barbados.

2. Botryocella borealis, Haeckel.

Lithobotrys borealis, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 294, Taf. ii.
%. 3.

Cephalis trilobate ; occipital lobe ovate, little longer than the two ovate frontal lobes. Thorax
about twice as long as the cephalis. Pores very numerous and small.
Dimensions. — Length of the shell 0-08, breadth 0'04.
Habitat. — North Atlantic, Greenland, depth 1000 to 2000 fathoms.

3. Botryocella tricellaris, n. sp.

Cephalis trilobate, with three odd sagittal lobes ; the middle or central lobe larger than the
anterior frontal and smaller than the posterior occipital lobe. Thorax nearly spherical, about as
long as the cephalis. Pores small and scarce.

Dimensions. — Length of the shell 0'08, breadth 0'06.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

1 Botryocella= Grape-pinnace ;

REPORT ON THE RADIOLARIA. 1117

4. Botryocella quadricellaris, n. sp. (PI 96, fig. 13).

Cephalis quadrilobate ; the helmet-shaped occipital lobe twice as long as the two paired
subspherical buccal lobes, and three times as long as the odd spherical frontal lobe. Thorax nearly
spherical, about as long as the cephalis.

Dimensions. — Length of the shell 01, breadth 0'05.

Habitat. — Central Pacific, Station 272, depth 4475 fathoms.

5. Botryocella quadrigemina, n. sp. (PI. 96, fig. 14).

Cephalis quadrilobate, with two pairs of lateral ovate lobes and complete sagittal constriction •
the two occipital lobes nearly twice as large as the two frontal lobes. Thorax ovate, separated
from the cephalis by a collar septum with four cortinar pores (fig. 14).

Dimensions. — Length of the shell 0-09, breadth 0~06.

Habitat. — Indian Ocean, Sunda Strait (Eabbe), surface

6. Botryocella multicellaris, n. sp. (PL 96, fig. 12).

Cephalis multilobate ; occipital lobe helmet-shaped, very large, about twice as long and broad
as the frontal half of the shell, which is divided into six to eight small roundish clustered lobes.
Thorax subspherical, of about the same size as the cephalis.

Dimensions. — Length of the shell O'l, breadth 0'05.

Habitat. — South Pacific Station 297, depth 1775 fathoms.

Genus 491. Lithobotrys,1 Ehrenberg, 1844, Monatsber. d. k. preuss.
Akad. d.Wiss. Berlin, p. 74.

Definition. — L ithobotryida with tubes on the cephalis, and with the mouth of
the thorax closed.

The genus Lithobotrys, the oldest and first known of the Botryodea, was founded
by Ehrenberg in 1844, and was one of his five oldest genera of Polycystina. It repre-
sented by itself the suborder Botryodea until the year 1860. The numerous species
described by Ehrenberg belong to very different genera of Botryodea, and partly also
of Spyroidea. Following Biitschli (1882) we retain here the name Lithobotrys for
those species, the type of which is Lithobotrys geminata. The genus Lithocorythiiim of
Ehrenberg is for the greater part identical with it. When in the preceding genus Acrobotrys
the mouth of the thorax becomes closed by lattice work, Lithobotrys arises. In the latter
as well as in the former the number of tubes on the cephalis is different, and may
characterise different subgenera.

1 Lithobotrys= Stone grape ; Ti/tfb

1118 THE VOYAGE OF H.M.S. CHALLENGER.

1. Lithobotrys geminata, Ehrenberg.

Lifhobotrys geminata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p 76, Taf. iii.

fig. 19.
Lithobotrys geminata, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 519, Taf. xxxiii.

fig. 27, a to e.
1 Lithocori/thium platylophus, Ehienberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78,

Taf. iv. fig. 5.

Cephalis trilobate, with a single apical tube in the apex of the helmet-shaped occipital lobe,
which is one and a half times as long as the two subspherical frontal lobes. Thorax ovate, one and
a half times as long as the cephalis, with few small pores in six to eight transverse rows.

Dimensions. — Length of the shell O'l, breadth 0'05.

Habitat. — Fossil in Barbados.

2. Lithobotrys lithocorythium, Haeckel.

Lithocorythium oxylophus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78,

Taf. iv. figs. 3, 4.

ILithopera oxystauros, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii.
fig. 6.

Cephalis trilobate, with a single apical horn or a pointed tube in the apex of the helmet-shaped
occipital lobe, which is a little longer than the two ovate frontal lobes. Thorax ovate, about as
long as the cephalis, with very numerous and small pores.

Dimensions. — Length of the shell 0'08, breadth 0'04.

Habitat. — Fossil in Barbados.

3. Lithobotrys nasuta, Ehrenberg.

Lithobotrys nasuta, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iii. fig. 21.

Cephalis quadrilobate, with a single descending sternal or nasal tube on the base of the anterior
or frontal lobe, which is half as long as the helmet-shaped occipital lobe and twice as large as the
two lateral buccal lobes. Thorax ovate, twice as long as the cephalis. Pores rather large,
circular.

Dimensions. — Length of the shell Oil, broad 0'05.

Habitat. — Fossil in Barbados.

4. Lithobotrys ornata, Ehrenberg.

Lithobotrys ornata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iii. fig. 18.

Cephalis quinquelobate, with two divergent ascending tubes, a posterior occipital and an anterior
sternal or nasal tube. Occipital lobe campanulate, twice as large as the two frontal, and four times
as large as the two buccal lobes. Thorax ovate, twice as long as the cephalis. Pores scarce and
small. The specimen figured by Ehrenberg is very incomplete.

Dimensions. — Length of the shell 0'09, breadth O05.

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1119

5. Lithobotrys sphcerothorax, n. sp. (PI. 96, fig. 15).

Cephalis trilobate, with two divergent cylindrical tubes, an ascending apical tube in the apex of
the ovate occipital lobe, and a descending sternal or nasal tube in the campanulate frontal lobe ;
between the two lobes a smaller central lobe,. Thorax spherical, twice as long as the latter. Pores
very small, numerous.

Dimensions. — Length of the shell O08, breadth 0-06.

Habitat. — Western Tropical Pacific, Station 225, depth 4575 fathoms.

6. Lithobotrys mascula, n. sp. (PI. 96, fig. 16).

Cephalis sexlobate, with two divergent cylindrical tubes, an ascending apical tube in the apex
of the helmet-shaped occipital lobe and a descending sternal tube on the base, between the two
kidney-shaped frontal lobes. The latter are half as large as the odd occipital lobe and of about the
same size as the two inflated lateral buccal lobes, which are separated by a small odd nasal lobe.

Dimensions. — Length of the shell 013, breadth 0-08.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

7. Lithobotrys orchidea, n. sp. (PL 96, fig 17).

Cephalis sexlobate, similar to the preceding species, but with five divergent and curved cylin-
drical tubes, which correspond to the five spines of Stephanium ; an apical tube on the apex of the
occipital lobe, a caudal tube on its base, a sternal tube between the two frontal lobes, and two
paired pectoral tubes between the latter and the lateral buccal lobes. Pores small and scarce.

Dimensions. — Length of the shell 0'12, breadth 0'06.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Family LVIII. PYLOBOTRYIDA, Haeckel (sensu emendato).

Pylobotryida, Haeckel, 1881, Prodromus, p. 440.

Definition. — Botryodea trithalamia, the shell of which is composed of a lobate
cephalis, a thorax, and an abdomen.

The family Pylobotryida comprises those Botryodea in which the shell
exhibits two parallel transverse annular constrictions, and is divided by these into three
successive joints, corresponding to the cephalis, the thorax, and the abdomen of the
Tricyrtida. As in the latter, the abdomen is here also a later production, arising
from the terminal mouth of the thorax; therefore the Pylobotryida must be derived
phylogenetically from the Lithobotryida.

Two genera of Pylobotryida were incompletely described in 1860 by Ehrenberg,
Botryocyrtis and Botryocampe. We retain them here, with a stricter definition, how-
ever. Two other genera were added in my Prodromus — Pylobotrys and Phormobotrys.

1120 THE VOYAGE OF H.M.S. CHALLENGER

The small number of species here enumerated may be easily increased, since numerous
forms, belonging probably to this family, are not sufficiently known. Their study is,
however, very difficult and requires accurate examination of the tiny shells from different
sides.

The four genera of Pylobotryida, here described, represent two different subfamilies.
The terminal mouth of the abdomen remains open in the Botryocyrtida, whilst it
becomes closed by a lattice-plate in the Botryocampida. There are in both groups
shells with and without porous tubes; the number of these tubes, and also the number
and disposition of the lobes in the cephalis, exhibit remarkable differences in the different
species of those genera, and may in future serve for their division into a greater number
of genera.

Synopsis of the Genera of Pylobotryida.

I. Subfamily ( Cephalis without porous tubes, . . .492. Botryocyrtis.

Botryocyrtida.
Mouth of the abdomen open. ( Cephalis with a variable number of porous tubes, . 493. Pylobotrys.

II. Subfamily^ _^ f Cepnalis ^thout porous tubes, , . . 494. Botryocampe.

1 CePhaUs with a variable number of porous tubes, . 495. Phormobotrys.

Genus 492. Botryocyrtis,1 Ehrenberg, i860, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 829.

Definition. — P ylobotryida without tubes on the cephalis, and with the mouth
of the abdomen open.

The genus Botryocyrtis, founded by Ehrenberg upon two Indian species, is the
simplest among the Pylobotryida. It may have been derived from Botryopyle by the
development of an abdomen (or a third shell-joint), the mouth of which remains open.

1. Botryocyrtis serpentis, Ehrenberg.

Botryocyrtis serpentis, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. x.
fig. 21.

Cephalis quadrilobate ; the odd frontal and the two paired buccal lobes subspherical, about half
as large as the odd occipital lobe. Thorax inflated, about as long as the cephalis and half as long as
the ovate abdomen. Mouth of the latter constricted, of half the breadth.

Dimensions. — Length of the shell 012, breadth 0'06.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms, Pullen.

1 Bo tryocyrtis= Basket with grapes ;

REPORT ON THE RADIOLARIA. 1121

2. Botryocyrtis theocampe, n. sp. (PI. 96, fig. 19).

Cephalis quadrilobate ; the odd frontal and the two paired buccal lobes hemispherical, about
half as large as the helmet-shaped occipital lobe. Thorax cylindrical, of equal length and breadth,
one and a half times as broad as the cephalis and as the cylindrical abdomen. Pores rather large,
irregular, roundish.

-Dimensions. — Length of the shell 012, breadth 0'06.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Botryocyrtis cerebellum, n. sp. (PL 96, fig. 18).

Cephalis quinquelobate ; the odd frontal and the two paired buccal lobes ovate, about half as
large as the two helmet-shaped paired occipital lobes (?). Thorax campanulate, twice as broad and
long as the cephalis and as the truncate cylindrical abdomen.

Dimensions. — Length of the shell 012, breadth 0-08.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Botryocyrtis quinaria, Ehrenberg.

Botryocyrtis quinaria, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. x.
fig. 16.

Cephalis quinquelobate ; the odd occipital lobe ovate, twice as large as each of the other four
subspherical lobes, the two anterior (or frontal) of which are somewhat smaller than the two
posterior (or buccal). Thorax campanulate, somewhat larger than the truncate abdomen. Pores
rather large, irregular.

Dimensions. — -Length of the shell 0'09, breadth 0'05.

Habitat. — Indian Ocean (Zanzibar and Madagascar), surface.

Genus 493. Pylobotrys,1 Haeckel, 1881, Prodromus, p. 440.

Definition. — P ylobotryida with tubes on the cephalis, and with the mouth of
the abdomen open.

The genus Pylobotrys differs from the closely allied Acrobotrys, its ancestral form,
in the development of an abdomen or a third shell-joint, the basal mouth of which
remains open.

1. Pylobotrys putealis, n. sp. (PI. 96, fig. 21).

Cephalis multilobate, with a single curved and descending tube on the base of its anterior
part (sternal tube). Occipital half of the cephalis divided into three large odd lobes (the largest

1 Pylobotrys = Grape with an aperture ; •s-i/An, /2<n-^.
(ZOOL. CHALL. Exp. — PART xi.,. — 1886.) Kr 141

1122 THE VOYAGE OF H.M.S. CHALLENGER.

the apical) ; facial half divided into three to five lobes, an odd frontal and one or two lateral pairs
of small buccal lobes. Thorax truncate conical, about as large as the cephalis and larger than
the truncate abdomen. Pores regular circular.

Dimensions. — Length of the shell 012, breadth 0'08.

Habitat. — Tropical Atlantic Station 347, depth 2250 fathoms.

2. Pylobotrys fontinalis, n. sp. (PL 96, fig. 20).

Cephalis trilobate, with three ovate lobes in the sagittal plane, of nearly equal size, and two
divergent cylindrical tubes conical at the base. An ascending apical tube on the apex of the
occipital lobe and a descending sternal tube on the base of the frontal lobe. The middle lobe
between the former distinctly exhibits in the apical view (fig. 20) the collar septum with the four
cortinar pores. Thorax campanulate, larger than the cephalis and the truncate abdomen.

Dimensions. — Length of the shell Oil, breadth 0-06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Pylobotrys cerebralis, n. sp. (PL 96, fig. 22).

Cephalis multilobate, with four divergent cylindrical tubes, which are cylindrical, obliquely
truncate at the mouth, and correspond in position to the four typical spines of Cortina ; an
ascending apical tube and three descending basal tubes (an odd caudal and two paired pectoral).
The helmet-shaped occipital lobe is about as large as the frontal half of the cephalis, which is
divided into three pairs of smaller pyriform lobes. Thorax subspherical, about as large as the
cephalis and half as large as the inflated abdomen. Pores very scarce and small.

Dimensions. — Length of the shell 015, breadth 0'08.

Habitat. — Indian Ocean, Cocos Islands, Eabbe, surface.

Genus 494. Botryocampe,1 Ehrenberg, 1860, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 829.

Definition. — P ylobotryida without tubes on the cephalis, and with the mouth
of the abdomen closed.

The genus Botryocampe may be derived from Botryocyrtis by development of a
basal lattice-plate, closing the terminal mouth of the abdomen. It is at the same time
closely allied to the Tricyrtid Theocapsa, and may be perhaps derived from this by
lobation of the cephalis.

1 Botryocampe = Caterpillar with a. grape ;

REPORT ON THE RADIOLARIA. 1123

1. Botryocampe inflata, Ehrenberg.

Botnjocampe inflata, Ehrenberg, 1861, Monatsber. d. k. Akad. d. Wiss. Berlin, p. 296 ;

Abhandl. d. k. Akad. d. Wiss. Berlin, 1872, p. 285, Taf. ii. fig. 4.
Botryocampe inflata, Haeckel, 1862, Monogr. d. RadioL, p. 345.
Lithobotrys inflata, Bailey, 1856, Amer. Journ. Sci. and Arts, vol. xxii. p. 1, pi. i. fig. 15.

Cephalis trilobate, inflated, of about the same breadth and length as the tun-shaped thorax and
the hemispherical abdomen. Frontal lobes of the cephalis ovate, a little smaller than the ovate
odd occipital lobe. Pores numerous and small.

Dimensions. — Length of the shell 0'05 to 0'08, breadth 0'02 to 0'04.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific, Stations 267 to 274, 241, 354, &c.,
surface, and in various depths.

2. Botryocampe theocapsa, n. sp.

Cephalis trilobate, half as long as the campanulate thorax, and one-third as long as the ovate
abdomen. Frontal lobes subspherical, scarcely half as long as the helmet-shaped occipital lobe.
Pores very small and scarce.

Dimensions. — Length of the shell 0'12, breadth O04.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

3. Botryocampe galea, Haeckel.

Lithobotrys galea, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 83.
Lithocorythium galea, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 29, a, b.
L/thocorythimn galea, Haeckel, 1862, Monogr. d. Radio!., p. 330.

Cephalis quinquelobate, about as large as the ovate thorax, and twice as large as the hemispher-
ical abdomen (which is identical with the " crista obtusa finis anterioris " of Ehrenberg). Occipital
lobe helmet-shaped, about twice as long as the two pairs of lateral lobes (the superior frontal and
the inferior buccal lobes).

Dimensions. — Length of the shell 0'08, breadth 0'04.

Habitat. — Fossil in Barbados.

4. Botryocampe rotalia, n. sp. (PI. 96, fig. 23).

Cephalis quinquelobate, half as large as the campanulate thorax and the subspherical abdomen.
Occipital lobe ovate, one and a half times as long as the two ovate frontal lobes, and three times
as long as the two subspherical buccal lobes. Collar septum with six distinct cortinar pores
(two anterior jugular, two middle cardinal and two posterior cervical, fig. 23).

Dimensions. — Length of the shell 01, breadth 0~06.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

1124 THE VOYAGE OF H.M.S. CHALLENGER.

5. Botryocampe camerata, n. sp. (PI. 96, fig. 24).

Cephalis multilobate, about as long and half as broad as the irregularly campanulate thorax,
which is half as long as the subspherical large abdomen. Occipital lobe of the cephalis helmet-
shaped, larger than its uviform frontal part, which is divided into six to eight small subspherical
lobes. In the interior of the thorax and abdomen irregularly branched rods are visible, which
divide their inner space into compartments or incomplete chambers. Pores large, regular,
circular, hexagonally framed.

Dimensions. — Length of the shell 015, breadth 009.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 495. Phormobotrys,1 Haeckel, 1881, Prodromus, p. 440.

Definition. — P ylobotryida with tubes on the cephalis, and with the mouth
of the abdomen closed.

The genus Phormobotrys differs from the similar and closely allied Pylobotrys in
the development of a basal lattice-plate closing the terminal mouth of the thorax, and
corresponds therefore to Lithobotrys among the Lithobotryida. As in the latter and in
Cannobotrys, &c., so here in Phormobotrys, different subgenera may be distinguished,
according to the different number and disposition of the radial tubes which become
developed from the lobate cephalis.

1. Phormobotrys trithalamia, n. sp. (PL 96, fig. 26).

Cephalis trilobate, with a single apical tube, which is only one-third as long, spindle-shaped,
pointed, with frontal opening. Frontal lobes ovate, two-thirds as long as the helmet-shaped
occipital lobe. Internal frontal septum of the cephalis with four large pores. Thorax cylindrical,
twice as long as the hemispherical abdomen. Pores small and numerous, irregular, roundish.

Dimensions. — Length of the shell 016, breadth 0'05.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Phormobotrys pentathalamia, n. sp. (PI. 96, fig. 27).

Cephalis quinquelobate, with a single conical apical tube of the same length, which has an
obliquely truncate frontal opening. Odd frontal and paired buccal lobes smaller than the sternal
and the occipital lobe. Internal frontal septum with six large pores. Thorax inflated, a little
larger than the subspherical abdomen. Pores subregular, circular.
Dimensions. — Length of the shell 015, breadth 0'08.

*.— Central Pacific, Station 272, depth 2600 fathoms.
1 Phormobotrys = Grape basket ;

REPORT ON THE RADIOLARIA. 1125

3. Phormobotrys hexathalamia, Haeckel.

Botryocarnpe hexathalamia, Haeckel, 1862, Monogr. d. Radiol., p. 344, Taf. xii. fig. 10.

Cephalis sexlobate, with a single apical horn, which is solid, vertical, cylindrical, pointed, only
one-third as long. Frontal lobes subcylindrical, nearly as long as the kidney-shaped occipital lobe,
three to four times as long as the small buccal lobes and the odd sternal lobe. Thorax tun-shaped,
smaller than the cephalis, larger than the hemispherical abdomen. Pores numerous, subregular,
circular.

Dimensions. — Length of the shell 013 to 015, breadth 0'05 to 0'06.

Habitat. — Mediterranean, Messina, surface.

4. Phormobotrys cannothalamia, n. sp. (PI. 96, fig. 25).

Cephalis trilobate, of about the same breadth and length as the campanulate thorax, which is
three times as long as the flat cap-shaped abdomen. The middle (or central) lobe of the cephalis is
simple, nearly cubical, and smaller than the ovate occipital and frontal lobe. The two latter are
prolonged into two slender cylindrical divergent tubes. Pores small and very numerous.

Dimensions. — Length of the shell 01, breadth 0-05.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

5. Phormobotrys polythalamia, n. sp.

Cephalis multilobate, of the same length and breadth as the subspherical thorax, and half as
long as the ovate abdomen. Occipital lobe helmet-shaped, about as large as the frontal half of the
cephalis, which is divided into six to eight lobes (two odd and two or three pairs of lateral lobes).
Four cylindrical tubes corresponding to the four typical spines of Cortina, an ascending apical and three
descending basal tubes (a posterior caudal and two anterior pectoral).

Dimensions. — Length of the shell 014, breadth 0'08.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

1126 THE VOYAGE OF H.M.S. CHALLENGER.

Suborder III. CYKTOIDEA, Haeckel, 1862.

• Cyrtida, Haeckel, 1862, Monogr. d. Radio!., pp. 272, 280.

Cyrtoidea vel Cyrtida, Haeckel, 1881, Prodromus, pp. 425—439.
Polycystina solitaria, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, pp. 53, 54.
Monodictya nassellaria, Ehrenberg, 1875, Abhandl. d. k. preuss. Akad. d.

Wiss. Berlin, pp. 156, 157.

Definition. — NASSELLARIA with a complete lattice-shell, exhibiting a simple or
reduced cephalis, which is neither bilocular nor lobate, without sagittal constriction.

The order Cyrtoidea, described by me in 1862 as the family Cyrtida, is by far
the largest of all the main groups of Radiolaria, and remarkable from the extraordinary
variety of forms and the number of species. In the following system more than eleven
hundred species are described, comprising about one-fourth of the number of species
in the whole class of Radiolaria. This astonishing variety, however, is not effected
by development of a large number of different types, but by an extraordinary
variability within certain restricted boundaries, similar to what is seen among
insects and birds. The number of genera, therefore, is comparatively small, and they
may all be disposed into four families only, which in my Monograph (1862, p. 280)
were distinguished as Monocyrtida, Dicyrtida, Tricyrtida and Stichocyrtida. If we
divide these four groups in the following pages into twelve families and twenty-
four subfamilies, we are guided by practical considerations only, hoping thereby to
give a better survey of the difficult labyrinth of Cyrtoidean morphology.

The Cyrtoidea are characterised by this wonderful richness of specific forms not
only in the present seas, but also for millions of years in the former ages of our globe.
The majority of all the fossil Radiolaria which are now known belong to this group, and
many species of it are so common, that great rocks are formed by their union. This
fact was first observed by Ehrenberg, who in his first system of Polycystina (1847,
loc. cit., p. 54) enumerated forty-four genera and two hundred and eighty-two species;
the Cyrtoidea, his Polycystina solitaria, form the preponderant majority of the
whole class, viz., twenty -five genera and one hundred and ninety -three species.

In this first system (of 1847), as well as in the last systematic table of Ehrenberg
(of '1875, loc. cit.}, the Cyrtida as "Polycystina solitaria" are opposed to all other
Radiolaria, as "Polycystina composita." The former bear the definition "Testae
silicese spatio interno ample pervio, aut passim levius transverse constricto " ; the latter,
however, " Testae silicese spatio interno celluloso aut strictura longitudinali constricto."
In reality these definitions are insufficient, and the conclusions which Ehrenberg derived

REPORT ON THE RADIOLARIA. 1127

from the organisation of the Polycystina solitaria and composita, were quite erroneous.
So also are the definitions of the three families into which he divided the Polycystina
solitaria, afterwards (in 1875) called by him " Monodictya nassellaria." These three
families were the Halicalyptrina, Lithochytrina and Eucyrtidina. With these were
also united the three genera of Botryodea known to Ehrenberg (Lithobotrys,
Botryocampe, Botryocyrtis). We entirely separate these here from the true Cyrtida,
on account of their lobate or multilocular cephalis.

Whilst Ehrenberg only knew the skeleton of the Polycystina solitaria, the first
observations of living Cyrtida were published by Johannes M tiller, 1858, in his funda-
mental treatise. He gave the first description and figures of the central capsule of this
group, with the characteristic lobes developed from its basal part ; and of the pseudo-
podia radiating on all sides (loc. cit., Taf. vi.). The forms described by him were all
Mediterranean, one Dicyrtid (Lithomelissa mediterranea), two Tricyrtids (Eucyrtidium
zancleum and Pterocanium charybdeum), and one Stichocyrtid (Lithocampe
tropeziana).

In my monograph (1862, p. 272—341) I gave a detailed description of all known
and some new Cyrtida, and characterised this family by the fundamental monaxonial
form of the shell, with two different poles (an upper apical and a lower basal pole), and
by the unipolar growth, beginning from the apical pole. I pointed out also the
peculiar structure of the monaxonial central capsule. At that time I divided the
Cyrtida into five subfamilies, in which, however, the Spyroidea ( = Zygocyrtida),
and the Botryodea ( = Polycyrtida) were united with the true Cyrtoidea
(Monocyrtida, Dicyrtida, Stichocyrtida).

The astonishing number of new and interesting forms of Cyrtida which I found in
the rich collection of the Challenger (beginning from 1876), and mainly in the
Radiolarian ooze of the Central Pacific (Stations 263 to 274), enabled me to give in
my Prodromus, in 1881, a greatly enlarged and amended system of this important
group. I separated there the Spyroidea ( = Zygocyrtida), and the Botryodea
( = Polycyrtida) from the true Cyrtoidea by restricted definition, pointing out the
essential differences in the structure of the cephalis in these groups ofCyrtellaria.
The latter name, as here used, is therefore identical with the " Cyrtida " of my
Monograph. In the Prodromus I divided the true Cyrtida (p. 426) into five sub-
families and thirty tribes, corresponding to the differences in the number of the shell-
joints and of the radial apophyses, and in the shape of the closed or open mouth. These
groups are here retained, but reduced to four families and twenty-four subfamilies,
since the Tetracyrtida are better united with the Stichocyrtida (compare below).

Richard Hertwig in his work Organismus der Radiolarien (1879, pp. 74 to 86)
gave the firs%t accurate description of the finer structure of the central capsule of the
Cyrtida, and pointed out their character as true MONOPYLEA, with porochora and

1128 THE VOYAGE OF H.M.S. CHALLENGER.

podoconus, and the peculiar shape of its nucleus. He also published excellent figures
of some interesting new species.

0. Biitschli, 1882, in his valuable paper entitled: " Beitrage zur Kentniss der
Radiolarien-Skelette, insbesondere der der Cyrtida" (Zeitschr. flir wiss. Zool., vol.
xxxvi. p. 485) made an attempt at a natural classification of the Cyrtida, which he de-
rived from the Spyroidea or Zygocyrtida. As already mentioned above, we cannot
accept this essay as the foundation of a true natural system, since the affinities of
the Cyrtellaria (and of the NASSELLARIA as a whole) are far more complicated and
difficult than Biitschli supposed. His views were supported by accurate observations
only on the structure of the fossil Cyrtoideaof Barbados ; these, however, represent
the minority only of the genera, and many interesting and important forms (mainly of
true " Monocyrtida ") remained unknown to Biitschli. A great part, however, of his
observations are very useful, and his remarks on comparative morphology are very
suggestive.

The Cyrtoidea may be divided into families and subfamilies according to three
different principles, viz., (l) the number of joints into which the shell is divided by
transverse strictures ; (2) the number of radial apophyses which arise from the shell ;
(3) the shape of the basal mouth, which is either open or closed by a lattice-plate.
At present every attempt of classification in this large group must be more or less
artificial, since the affinities of the numerous smaller and larger groups are extremely
complicated, and the ontogeny, the only sure guide in this phylogenetical labyrinth, is
perfectly unknown. It seems therefore the most convenient to employ for our
artificial classification, first, the number of shell-joints, second, the radial structure, and
third, the shape of the mouth.

A. The number of joints into which the shell is divided by transverse constrictions,
serves here for the distinction of four primary groups or suborders of the Cyrtoidea,
viz., (1) Monocyrtida with one joint ; (2) Dicyrtida with two joints ; (3) Tricyrtida
with three joints ; and (4) Stichocyrtida with four or more joints. In my Prodromus
(1881, p. 426) I divided the latter group into Tetracyrtida (with four joints), and
Stichocyrtida (with five or more joints); but these two groups may be united, since the
fourth and all the succeeding joints are of rather indifferent shape and of little morpho-
logical value. The three first joints, however, are usually very different and possess a
high morphological importance, so that we distinguish the first joint as cephalis, the
second as thorax, and the third as abdomen. The uppermost transverse constriction,
which separates the two first joints, cephalis and thorax, is the collar stricture and is
usually caused by an internal fenestrated septum, the cortinar septum. The second con-
striction, which separates the second and third joints (thorax and abdomen) is called the
lumbar constriction. The following constrictions (in the Stichocyrtida) are indifferent
and of little morphological interest, and require therefore no peculiar designation.

REPORT ON THE RADIOLARIA.

1129

B. The radial structure, indicated by radial apophyses arising from the shell, offers
three principal differences, according to which the whole group of Cyrtoidea may
be divided into three large groups or sections, viz., (l) Pilocyrtida, or Cyrtoidea
triradiata, with three radial apophyses ; (2) Astrocyrtida, or Cyrtoidea multiradiata,
with numerous radial apophyses (four to nine or more) ; and (3) Corocyrtida, or
Cyrtoidea eradiata, without external radial apophyses. The majority of Cyrtoidea
are Pilocyrtida, with three radial apophyses, which are probably homologous to the three
primary feet of the Plectoidea and of Cortina (therefore " cortinar feet "). The
Astrocyrtida, or the Cyrtoidea with a variable number of radial apophyses (at least
four to six) may be derived from the Pilocyrtida by interpolation of secondary or
interradial apophyses between the three primary or perradial apophyses. The
Corocyrtida, however, or the Cyrtoidea without external radial apophyses, may have
originated by reduction and loss of the latter, either from the Pilocyrtida or from the
Astrocyrtida.

C. The shape of the basal mouth in the Cyrtoidea exhibits two essential
differences only, viz., (1) the terminal mouth of the shell is a simple wide opening in
the Stomocyrtida, or (2) the terminal mouth is closed by a lattice -plate, in the
Clistocyrtida. As these two different cases occur in all the twelve families, which we
have distinguished according to the differences in the number of joints and in the
radial structure, we get altogether twenty-four subfamilies which are synoptically
arranged in the following table : —

Synopsis of the four
sections, twelve families
and twenty-four subfamilies
of CYRTOIDEA.

PILOCYRTIDA.

Cyrtoidea triradiata.
(Three radial apophyses. )

ASTROCYRTIDA.
Cyrtoidea multiradiata.
(Four to nine or more apophyses.)

COROCYRTIDA.
Cyrtoidea eradiata.
(No radial apophyses.)

Mouth of the shell.

Apcrta.

Clausa.

Aperta.

Clausa.

Aperta.

Clausa.

MONOCYRTIDA.

(Cyrtoidea monothalaniia).

TRIPOCALPIDA.

PH.ENOCALPIDA.

CYRTOCALPIDA.

Archipilida.

Archiperida.

Archiphormida.

Archiphnenida.

Arehicorida.

Archicapsida.

DICYKTIDA.

(CyrtoiJea dithalamia).

TRIPOCYRTIDA.

ANTHOCYRTIDA.

SETHOC
Sethocorida.

YRTIDA.

Sethopilida.

Sethoperida.

Sethophormida.

Sethophsenida.

Sethoeapsida.

TR1CYRT1DA.

(Cyrtoidea trithalamin).

PODOCYKTIDA.

PHORMOCYRTIIJA.

THEOCYRTIDA.

Theopilida.

Theoperida.

Theophormida.

Theophamida.

Theocorida.

Theocapsida.

STICHOCYRTIDA.

(Cyrtoidea polythalamia).

PODOCAMPIDA.

PHORMOCAMPIDA.

LlTHOCAMPIDA.

Stichopilida.

Stichoperida.

Stichophormida. 1 Stiehopbsenida.

Stichocorida.

Stichocapsida.

(ZOOL. CHALL. EXP. — PART XL. 1886.)

Kr 142

1130 THE VOYAGE OF H.M.S. CHALLENGER.

The cephalis, or the first shell-joint of the C y r t o i d e a, is in the majority homo-
logous with the cephalis of the Spyroidea, from which it differs in the reduction of
the sagittal ring and the absence of the corresponding sagittal constriction ; its cavity
is therefore simple, not bil ocular. Its homology with the original cephalis of the
S )p y r o i d e a cannot be doubted, when its base exhibits the typical basal pores of
the Semantida. But in many cases these are wanting, and in a great number of
Cyrtoidea (mainly of Monocyrtida) there is more or less evidence that the original
cephalis is lost, and that the real first joint is the thorax, the original second joint.
At present it is quite impossible to distinguish between the former and the latter shells,
and therefore in the following descriptions the first joint is always named cephalis and
the second thorax. In future, when the affinities of the Cyrtoidea become better
known, it will be necessary to distinguish the " Archicephalis," or the true cephalis of
all Spyroidea and of the majority of Cyrtoidea, from the " Pseudocephalis " or
the false cephalis of the minority (e.g., of many Monocyrtida aperta, Archipilida, Archi-
phormida, Archicorida, &c.).

The thorax, or the second shell-joint of the Cyrtoidea, is in the majority homo-
logous with the thorax of the Phormospyrida and Androspyrida, and therefore developed
by apophyses, which arise from the base of the cephalis and become united by transverse
branches forming a lattice-plate. Its size is generally In inverse proportion to that
of the cephalis. The more the cephalis becomes reduced, the more the thorax is
developed. Its form is very variable, usually three-sided pyramidal or prismatic in
the triradiate, polyhedral in the multiradiate, and conical or cylindrical in the eradiate
Cyrtoidea. Its terminal mouth is either a simple wide opening, or closed by a
lattice-plate. In the majority of Cyrtoidea the thorax is separated from the cephalis
not only by the external collar constriction, but also by the internal cortinar septum, a
horizontal lattice-plate which exhibits the typical basal pores of the Semantida (usually
two smaller jugular and two larger cardinal pores). But this septum is often reduced
or perfectly lost, and then the external collar constriction alone indicates the separation
of the cephalis and the thorax.

The abdomen, or the third shell-joint of the Cyrtoidea, absent in the Mono-
cyrtida and Dicyrtida (as also in all S p y r o i d e a), occurs constantly in all Tricyrtida
and Stichocyrtida. It is a simple large chamber in the Tricyrtida, but forms an annu-
lated body, composed of a variable number of successive joints, in the Stichocyrtida.
The constrictions between these joints, and also the lumbar constriction, between abdomen
and thorax, are usually provided with a lattice-girdle, projecting into the cavity of the
shell, like a diaphragm. Usually this horizontal girdle bears only a single circle of pores,
rarely two or more. In many Cyrtoidea it is replaced by a solid horizontal ring of
silex, and often it is wanting. It originates by the insertion of the following shell-joint,
which takes place not on the terminal mouth of the preceding joint, but somewhat above it.

REPORT ON THE RADIOLARIA. 1131

The annular joints of the Stichocyrtida succeeding the third joint, and very
variable in number, may be regarded either as a series of new postabdominal chambers,
succeeding the true abdomen, or as secondary joints of the annulated abdomen itself.
The latter view may be sustained by the fact that these joints are usually of an indif-
ferent shape, and do not possess the characteristic features which we find in the first three
joints, the abdomen, the thorax and the cephalis.

The lattice-work of the shell exhibits in the Cyrtoidea an extraordinary variety,
similar to that of the Sphseroidea; it serves in the first place for the distinction of
species. The three first joints of the shell are often distinguished by the different char-
acter of the lattice-work. The cephalis has usually very small and simple pores. The
lattice-work of the thorax is often characterised by radial structures. The pores of the
abdomen are usually very numerous and regular. The numerous joints in the annulated
abdomen of the Stichocyrtida commonly exhibit little vai'iety.

The closure of the mouth, effected by a convex or horizontal terminal lattice-plate,
has a different signification in the Monocyrtida and in the jointed Cyrtoidea. In the
Monocyrtida clausa this closing plate is the original cortinar plate or the basal plate of
the cephalis. In the jointed Cyrtoidea, however, the lattice-plate which closes the
terminal mouth of the thorax or of the abdomen (of the last annular joint in the Sticho-
cyrtida), is produced by central union of the convergent edges, which grow centripetally
from the margin of the mouth of the last joint towards its centre.

The radial apophyses arising from the shell of the Cyrtoidea may probably
be always derived from that tripodal structure which is found in all P 1 e c t o i d e a, in
Cortina and Cortiniscus among the Stephoidea, and in the majority of S p y r o i d e a,
Therefore the prototype of this radial structure would be Plagoniscus and Cortina, with
four radial spines united in a common point, the cortinar centrum ; an ascending apical
horn and three descending basal feet. The odd posterior or caudal foot is usually
similar in shape to the two paired anterior or pectoral feet, but may be distinguished
from these latter by its relation to the apical horn. Very frequently an internal vertical
free columella arises in the cephalis, or instead of it an ascending rib in the dorsal wall
of the cephalis, which connects the base of the apical horn with the origin of the caudal
foot. This is probably the remaining part of the sagittal ring. More rarely also a part
of the ventral rod of the latter is preserved, or on the anterior pole of the basal rod of
the cephalis an ascending procolumella arises which is inserted on the frontal face of the
cephalis, and sometimes prolonged into a nasal horn (the rod, C, of Biitschli). These
two odd horns, the posterior apical horn and the anterior nasal horn, are usually different
and divergent. In some genera a variable number of accessory radial horns is developed
on the convex face of the cephalis. In many hornless genera the free apical horn is
lost, but not unfrequently the columella is preserved which connects the caudal foot
with that point of the cephalis, in which formerly the apical horn was inserted.

1132 THE VOYAGE OF H.M.S. CHALLENGER.

The three primary radial beams, corresponding to the three basal feet of Plectaniscus
and Cortina, exhibit in the Cyrtoidea the greatest variety in form and size, and
chiefly in their relation to the shell, the latter serving mainly for the distinction of
genera. Originally these three cortinar beams arise from the basal plate of the cephalis,
the odd caudal foot appearing as a prolongation of the basal rod of that plate, and the
paired pectoral feet as prolongations of its coracal rods (between the jugular and cardinal
pores). The lattice-work of the thorax is developed usually between the three cortinar
feet, more rarely inside or outside of them. Therefore the three beams appear
commonly as three divergent ribs in the wall of the thorax, and continue over its basal
mouth as three free terminal feet. With the increasing length of the shell and the number
of its joints the three radial ribs are also prolonged, and their free distal ends may
be prominent at very different points, either as three lateral wings or as three terminal
feet. These are either solid spines or lattice-plates, sometimes more or less ramified.

The three radial apophyses are prevalent in the majority of the Cyrtoidea,
which we call " Pilocyrtida " (or Cyrtoidea triradiata). Their number increases in the
Astrocyrtida (or Cyrtoidea multiradiata). The most frequent cases of multiplication are
here caused by the development of six or nine radial apophyses ; these may be enclosed
ribs, or lateral wings, or terminal feet. In the sexradial Cyrtoidea there are three
secondary or interradial apophyses interpolated between the three primary or perradial ;
in the nine-radial Cyrtoidea, however, there are six adradial apophyses interpolated.

A third and last great group is formed by the Corocyrtida or Cyrtoidea eradiata.
These exhibit no radial apophyses, neither enclosed ribs, nor free lateral wings, nor
terminal feet. But in a great number of them internal traces of an original triradiate
structure are visible, mainly in the cortinar septum between cephalis and thorax ; this
often exhibits three or four, and sometimes six cortinar or collar pores, of the same
typical shape as in the triradial Spyroidea. Sometimes even an internal columella
with three radial branches is preserved, as in Axocorys. It is therefore very probable
that a great part of these Cyrtoidea eradiata (if not all) may be derived from triradiate
or multiradiate ancestral forms, by reduction and loss of the radial apophyses. In
another part of this group, mainly in the Monocyrtida eradiata (Cyrtocalpida) it is
possible, or even probable, that their eradiate shell has originated independently from
Nassellida, and that they have no true relation to radial Cyrtoidea.

The Central Capsule of the Cyrtoidea, first observed by J. Miiller (1858), and
more fully described in my Monograph (1862), was very accurately examined by
Richard Hertwig (1879). His observations were confirmed by numerous new forms,
which I was able to examine in well-preserved preparations of the Challenger. The central
capsule, according to these, exhibits the same typical shape, which is characteristic of all
MONOPYLEA. (with porochora and podoconus), and may be derived with the latter from the
common ancestral forms, Cystidium and Nassella ( — the skeletonless Nassellida). In

REPORT ON THE RADIOLARIA.

1133

the majority, however, of Cyrtoidea, the capsule develops on its basal face a number
of depending lobes, as were also found in some Spyroidea (and probably also
B o t r y o d e a). In this respect we may distinguish two main forms of the capsule in the
Cyrtellaria, viz., the primary simple, not lobate form, and the secondary lobate form.
The central capsule is originally always enclosed in the cephalis, and has there a simple,
subspherical, ellipsoidal or ovate form. As soon as their growth increases, and the enclosing
cephalis becomes too narrow, it sends out prolongations in the form of basal lobes, which
depend from its base, and proceed through the pores of the basal lattice of the cephalis, or
the cortinar pores. In the great majority of Cyrtoidea in which the capsule was
observed, either three or four such lobes were seen (already described by J. Miiller). Of
course this number depends upon the number of cortinar pores, which is either three or
four ; therefore in the Cyrtoidea with three pores in the cortinar plate, we find three
lobes of the central capsule (an odd posterior and two paired anterior) ; in the
Cyrtoidea, however, with four pores in the cortinar plate (the majority) we find four
lobes of the central capsule (two smaller anterior jugular and two larger posterior cardinal
lobes). Usually each lobe is ovate or pear-shaped and encloses a large oil-globule, and
often also an apophysis of the cell-nucleus.

Section I. MONOCYETIDA, Haeckel, 1862, Monogr. d. Radiol, pp. 280, 281.

Definition. — Cyrtoidea monothalamia, with simple, not jointed shell (or cephalis),
without transverse constrictions.

Family LIX.

Tripocalpida.
Three radial apophyses.

Synopsis of the three Families and six Subfamilies of Monocyrtida.

| Mouth open, . .1. Archipilida.

j Mouth closed, . . . . .2. Archiperida.

| Mouth open, . . 3. Archiphormida.

Family LX.

Phaenocalpida.

Numerous radial apophyses.

Family LXI.

Cyrtocalpida.
No radial apophyses.

) Mouth closed, .
\ Mouth open,
) Mouth closed,

4. Archiphaenida.

5. Archicorida.

6. Archicapsida.

Family LIX. TRIPOCALPIDA, n. fam.

Archipilida et Archiperiila, Haeckel, 1881, Prodromus, pp. 427, 429.

Definition. —Monocyrtida triradiata. (Cyrtoidea with a simple, not jointed shell,
representing a simple cephalis, with three radial apophyses.)

1134 THE VOYAGE OF H.M.S. CHALLENGER.

The family Tripocalpida, composed of the Archipilida and Archiperida of my
Prodromus, comprises those Cyrtoidea in which the lattice-shell is quite simple,
without transverse constriction, and bears three radial apophyses. The two subfamilies
differ in the shape of the basal mouth, which in the Archipilida is a simple wide opening,
in the Archiperida closed by a lattice-plate ; the former are here divided into eight, the
latter into seven different genera.

Only three species of this family were hitherto described, all three belonging to the
Archipilida, viz., (l) Tripocalpis galea (fossil in Barbados, figured by Ehrenberg, 1875,
as Halicalyptra galea), (2) Tripodiscium campanula (fossil in Sicily, figured by Stohr,
1880, as Carpocanium) ; and (3) Tridictyopus elegans, of which Richard Hertwig gave an
excellent description in 1879, with an accurate figure of the central capsule. All the
other species of the family (seventy) are new.

The shell in the majority of Tripocalpida is ovate or campanulate, sometimes conical
or three-sided pyramidal. Three radial apophyses are constantly distinct, either three
lateral wings or three terminal feet ; these are usually solid spines, rarely lattice-plates.
The top of the shell usually bears an apical horn, rarely two or more horns ; often the
horn is wanting. The lattice-work of the shell is very various in the different species, and
often of a remarkable structure (PI. 51, figs. 6-8 ; PI. 98, figs. 4-8). The cavity of the
shell is in all Archipilida, and in a part of the Archiperida (Peridium, Archipera,
Archibursa) quite simple. In the other part of the Archiperida, however, constituting
the peculiar group of Euscenida (genera 504-507), a vertical columella arises in the
centre of the basal plate, and is prolonged upwards in the apical horn ; this columella is
either simple (Euscenium, Archiscenium) or branched (Cladoscenium, Pterosceniitm) ;
in the latter case the ascending branches are disposed in triradiate verticils and are
inserted on the inner face of the shell (compare PI. 53, figs. 11-16, and PI. 98,
figs. 1-4).

The phylogenetic origin of the Tripocalpida may be very divergent, and their morpho-
logical affinity to the other NASSELLARIA is a very complicated problem. The Euscenida
(genera 504-507) may be derived directly from the Plagonida (Plagoniscus) or Plectanida
(Plectaniscus). The Archibursida (genera 508-510) however, manifest a closer affinity
to the Tripospyrida, and may be derived from them by reduction of the sagittal ring and
constriction. In these two groups of Archiperida the shell may be regarded as a true
cephalis. In the Archipilida, however, where the shell has a wide basal opening and the
three radial ribs arise originally from the base of the apical horn, the shell itself may
correspond to the thorax of the Dicyrtida, and may be derived from these by loss of the
cephalis. This is the more probable, as sometimes a small remnant of the reduced
cephalis is preserved (PL 98, fig. 8). None of these difficult questions can be answered
until a much closer morphological knowledge of the Tripocalpida is acquired.

REPORT ON THE RADIOLARIA.

1135

I. Subfamily

Archipilida.
Basal mouth of the
shell a simple
wide opening.

II. Subfamily

Archiperida.
Basal mouth of the

shell closed by a

lattice-plate.

Synopsis of the Genera of Tripocalpida.

I Apex with a horn, .
( No apical horn,

> No apical horn,

( Apex with a horn, .
( No apical horn,
| Apex with a horn, .
j No apical horn,
Apex with a horn, .

Shell with three
lateral ribs or
wings, with or
without ter-
minal feet.

Shell without
lateral ribs or
wings but with
three terminal
feet.

Shell in its axis
witli a free (simple
or branched) in-
ternal columella,
prolonged into an
apical horn.

Three terminal feet.

Six to nine or more
terminal feet.

No terminal feet.

Feet simple or
branched, not lat-
ticed.

Feet latticed.

Shell with three
free feet, without
lateral lattice-

Columella simple, .
Columella branched,

Shell with three
lateral lattice-
wings, connecting
the three feet with
the horn.

Shell with simple cavity, without free
columella. Three free basal feet.

Columella simple, .
Columellabranched,

One apical horn,
Two or more horns,
|_ No apical horn,

496. Tripocalpis.

497. Tripodonium.

498. Tripterocalpis.

499. Trissopilium.

500. Archipilium.

501. Tripilidium.

502. Tripodiscium.

503. Trididyopm.

504. Euscenium.

505. Cladoscenium.

506. Archiscenium.

507. Pteroscenium.

508. Peridium.

509. Archipera.

510. Archibursa.

Subfamily 1. ARCHIPILIDA, Haeckel, 1881, Prodromus, p. 427.

Definition. — T ripocalpida with the basal mouth of the shell open (vel Mono-
cyrtida triradiata aperta).

Genus 496. Tripocalpis,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) with three lateral
ribs prolonged into three terminal feet. Apex with a horn.

The genus Tripocalpis opens the series of Archipilida, or of those Monocyrtida in
which the inonothalamous shell exhibits a distinct triradial structure, and a simple open
mouth, without cortinar lattice. Tripocalpis is probably the most primordial of the
Archipilida, and has three lateral ribs, which are prolonged into three free terminal

1 Tripocalpis = Urn with three feet ; rjiVoi/;

1136 THE VOYAGE OF H.M.S. CHALLENGED.

feet, and connected in the apex of the pyramidal or campanulate shell with the apical
horn. It may probably be derived from Dictyophimus by loss of the ceplialis. The
central capsule is simple, spherical, or ellipsoidal.

1. Tripocalpis plectaniscus, n. sp.

Shell three-sided pyramidal, smooth, about as long as broad, with irregular polygonal pores and
thin bars. Apical horn stout, three-sided pyramidal, about as long as the shell. From the three
edges of its base arise three prominent straight radial ribs, which are prolonged into three large
divergent feet, of equal size and the same form as the horn.

Dimensions. — Shell 01 diameter, horn and feet 012.

Habitat. — Tropical Pacific (Philippine Sea), Station 206, depth 2100 fathoms.

2. Tripocalpis galea, Haeckel.

Halicalyptra galea, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 74, Taf. ii. fig. 10.

Shell campanulate, rough, about as long as broad, with irregular roundish pores and thick bars.
Apical horn stout, three-sided pyramidal, scarcely one-fourth as long as the shell. Beyond its
base there arise three prominent, slightly curved lateral ribs, which are prolonged into three pyramidal,
slightly divergent stout feet, somewhat shorter than the shell

Dimensions. — Shell 0'08 to 0'09 diameter, horn 0'02, feet 0'07.

Habitat. — Fossil in Barbados.

3. Tripocalpis tricostata, n. sp.

Shell ovate campanulate, one and a half times as long as broad, with regular circular pores,
disposed in alternate longitudinal rows. Apical horn three-sided pyramidal, stout, half as long as
the shell. In the middle of the shell there arise three wing-like lateral ribs, which are prolonged
into three broad, slightly curved, divergent terminal feet.

Dimensions. — Shell 012 long, 0'08 broad, horn and feet O'OG to 0'08.

Habitat. — Fossil in Barbados.

4. Tripocalpis triserrata, n. sp. (PI. 51, fig. 6).

Shell ovate, nearly twice as long as broad. The three sides of the shell, between the three
large ribs, are provided each with nine delicate parallel, longitudinal, slightly curved ribs, alternating
with ten longitudinal rows of regular circular pores about as broad as the bars. Apical horn short
and broad, three-sided pyramidal ; from the three edges of its base there arise three wing-like serrate
main ribs, which are prolonged into three short pyramidal terminal feet.

Dimensions. — Shell 012 long, 0'07 broad, horn and feet O'Ol.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

REPORT ON THE RADIOLARIA. 1137

5. Tripocalpis cortinaris, n. sp. (PL 97, fig. 3).

Shell hemispherical, one and a half times as broad as long, with regular, circular, hexagonally
framed pores. Apical horn stout, three-sided pyramidal, with three serrate edges. From the base
of the latter arise three strongly dentate and curved lateral ribs, with recurved teeth, and these
are prolonged into the serrate convex edge of the three basal feet, which are crescentic and twice
as long as the shell.

Dimensions. — Shell 0'07 long, O'l broad; horn 0'06 long, feet 014 long.

Habitat.- — Indian Ocean, Cocos Islands (Eabbe), surface.

Genus 497. Tripodonium,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) with three
lateral ribs prolonged into three terminal feet. Apex without horn.

The genus Tripodonium differs from the preceding Tripocalpis, its probable
ancestral form, only in the loss of the apical horn (already very small in some forms of
the latter). It bears therefore to the latter the same relation that Sethopilium does
to Dictyophimus.

1. Tripodonium campanulatum, n. sp.

Shell campanulate, somewhat broader than high, with regular circular pores, twice as broad
as the bars. Three broad lateral wings, lamellar, triangular, are prolonged over the peristome into
three short triangular lamellar feet, one-fourth as long as the shell.

Dimensions. — Shell O08 long, 0'09 broad; feet 0'02 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Tripodonium ovatum, n. sp.

Shell ovate, one and one-third times as long as broad, with numerous and small circular pores,
scarcely as broad as the bars. Three prominent longitudinal ribs, arising in the lower half of the
shell-wall, are prolonged into three divergent conical curved feet, about half as long as the shell.

Dimensions. — Shell 0'12 long, 0'09 broad ; feet 0'06 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 498. Tripterocalpis,2 Haeckel, 1881, Prodromus, p. 428.

Definition. — Archipilida (vel Monocyrtida triradiata aperta) with three
lateral wings and a peristomial corona of numerous terminal feet. Shell ovate, with
constricted mouth, without apical horn.

1 Tripodonium =-- Shell with three feet. 2 Tnpterocalpis = 1Jm with three wings; t^-n^;, ***•*!;.

(ZOOL. CIIALL. EXP. PART XL. 1886.) El 143

1188 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Tripterocalpis is distinguished from the other Archipilida by the remark-
able combination of three lateral wings and of numerous (six to nine or more) terminal
feet. It may be derived directly from the preceding Tripodocalpis by multiplication
of the terminal feet. These are sometimes obliquely directed. The central capsule is
ellipsoidal or ovate, and fills up the greater part of the shell.

1. Tripterocalpis phylloptera, n. sp. (PI. 51, fig. 1).

Shell slender, ovate, nearly twice as long as broad. Pores circular, of different sizes and at
unequal distances. Along the lower half of the shell there arise three broad triangular lamellar wings.
Peristome with twelve conical, nearly parallel and vertical feet, about one-sixth as long as the shell.

Dimensions:- — Shell 0'2 long. 012 broad ; wings 01 long, feet 0'03 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Tripterocalpis conoptera, n. sp. (PI. 51, fig. 2).

Shell ovate, nearly as broad as long. Pores regular, circular, quincuncial, twice as broad as the
bars. In the middle of the shell there arise three conical, smooth, divergent wings, about half as
long as the shell. Peristome with six short triangular, oblique, convergent feet.

Dimensions. — Shell 016 long, 014 broad ; wings 0'09 long ; feet 0'02 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Tripterocalpis ogmoptera, n. sp. (PI. 51, figs. 3—5).

Shell ovate, nearly as broad as long. Pores small and numerous, circular or roundish, partly
confluent, double-contoured (fig. 4). In the middle of the shell there arise three very large
conical divergent wings, which are longitudinally striped and longer than half the shell. Peristome
with nine short triangular, oblique, convergent feet.

Dimensions. — Shell 018 long, 016 broad ; wings 012 long, feet 0'02 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 499. Trissopilium,^ Haeckel, 1881, Prodromus, p. 427.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) with three lateral
ribs or wings. Mouth smooth, without terminal feet. Apex with a horn.

The genus Trissopilium and the following nearly allied Archipilium differ from the
other Archipilida in the absence of terminal feet, the peristome being quite simple, and
truncate. But there are three lateral wings, arising either from the apex or from the
lateral sides of the m6nothalamous shell. TrissopiUuni may perhaps be derived from
Lithomelissa. by reduction of the cephalis.

1 Trissnpilinm - Small hat with three wings ;

REPORT ON THE RADIOLARIA. 1139

1. Trissopilium tetraplecta, n. sp.

Shell in the upper half three-sided pyramidal, in the lower half inversely hemispherical, of
equal length and breadth. Pores irregular, roundish, in the upper half larger. From the apex
there diverge four equal, straight and stout, three-sided pyramidal spines, one of which is vertically
ascending (the horn), the three others obliquely descending (the wings). The distal half of the
latter is free, whilst the proximal half forms three ribs, enclosed in the shell-wall. Mouth
constricted, half as broad as the shell.

Dimensions. — Shell 0'08 long and broad, horn and wings 01 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Trissopilium lithomelissa, n. sp.

Shell ovate, one and one-third times as long as broad. Pores circular, of different sizes, small
and numerous. Apical horn very large, straight, cylindrical, vertical, longer than the shell. Three
lateral wings shorter, arising from the middle of the shell, conical, curved, divergent. Mouth
truncate, two-thirds as broad as the shell.

Dimensions. — Shell Oil long, 0'08 broad; horn O'l 3 long, wings 0'09 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 500. Archipilium,1 Haeckel, 1881, Prodromus, p. 427.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) with three lateral
ribs or wings. Mouth truncate, without terminal feet. Apex without horn.

The genus Archipilium differs from the nearly allied Trissopilium, its probable
ancestral form, in the absence of the apical horn. The three lateral wings of the ovate
shell are stout spines. It may also be derived from the similar Sethopilium by reduc-
tion and loss of the cephalis.

1. Archipilium orthopterum, n. sp. (PI. 98, fig. 7).

Shell ovate, smooth, nearly cylindrical, scarcely broader than the truncate, widely open mouth.
Pores numerous, irregular, roundish, of very different sizes. Three lateral wings arising from the
middle zone, twice as long as the shell, straight, divergent, stout, cylindrical, longitudinally striped.

Dimensions. — Shell 0'08 long, 0'06 broad; wings 015 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Archipilium sigmopterum, n. sp.

Shell ovate, smooth, nearly campanulate, of equal length and breadth, %ne and one-third times
as broad as the truncate, slightly constricted mouth. Pores scarce, irregularly formed and

1 Archipilium= Primordial hat ;

1140 THE VOYAGE OF H.M.S. CHALLENGER.

scattered, of very different sizes. Three lateral wings, stout, prismatic, about as long as the shell
widely divergent and S-shaped, curved.

Dimensions. — Shell O08 diameter, wings O'OS long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Archipilium cyrtopterum, n. sp.

Shell ovate, rough, twice as broad as the constricted month. Pores small and numerous,
subregular, circular, smaller than the bars. Three lateral wings cylindrical, crescentic, in the upper
half divergent, in the lower convergent, one and one-half times as long as the shell.

Dimensions. — Shell 0'09 long, 0'07 broad ; wings 014 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Genus 501. Tripilidium,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) without lateral
ribs, with three simple or branched terminal feet and an apical horn.

The genus Tripilidium differs from Tripodonium in the absence of the three
lateral ribs, and may be derived either from this ancestral form, or directly from
Tripospyris (by loss of the sagittal ring and constriction); perhaps also from Lychno-
canium (by reduction of the cephalis). We distinguish as two subgenera Tristylocorijs
(with simple feet) and Tripodocorys (with branched feet).

Subgenus 1. Tristylocorys, Haeckel.
Definition. — Feet simple, not branched.

1. Tripilidium cortina, n. sp.

Shell campanulate, rough, about as long as broad. Pores subregular, circular, larger in the middle
zone, twice to three times as broad as the bars. Mouth constricted, half as broad as the shell.
Apical horn straight and stout, three-sided pyramidal, about as long as the shell. Three feet
divergent, slightly S-shaped, curved, somewhat longer than the shell.

Dimensions. — Shell 01 diameter, horn 0'09 long, feet 0'13 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Tripilidium hemisphcericum, n. sp.

Shell hemispherical; smooth, nearly twice as broad as long. Pores large, with thin bars,
irregular, roundish, of very different sizes. Mouth wide open. Apical horn conical, half as long as

1 Tri'fiiliditcm = Small hat with three feet ; TJ<«, xihtiiov.

REPORT ON THE RADIOLARIA. 1141

the shell. Three feet slender cylindrical, widely divergent, curved, nearly twice as long as the
shell.

Dimensions.^She]! 0'08 long, 014 broad; horn O'Oo long, feet 015 long.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

3. Tripilidium lychnocanium, n. sp.

Shell hemispherical, thorny, one and a half times as broad as long. Pores regular, circular,
hexagonally framed, as broad as the bars. Mouth slightly constricted. Apical horn stout and
short, three-sided pyramidal. Three feet cylindrical, straight, divergent, twice to three times as long
as the shell. (Similar to Lychnocanium favosum, PI. 61, fig. 6, perhaps derived from it by reduction
of the cephalis.)

Dimensions. — Shell 0'08 long, 012 broad ; horn 0'02 long, feet 0'2 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Tripilidium ovatum, n. sp.

Shell ovate, smooth, one and a half times as long as broad. Pores regular, circular, as broad as
the bars. Mouth constricted, half as broad as the shell. Horn short, conical. Three feet conical,
curved, convergent, scarcely one-third as long as the shell.

Dimensions. — Shell 015 long, Oil broad; horn 0'02 long, feet 0'04 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

5. Tripilidium clavatum, n. sp.

Shell nearly spherical, tuberculate, a little broader than long. Pores regular, circular, as broad
as the bars. Mouth constricted, half as broad as the shell. Apical feet and the three divergent
feet of equal size and similar form, about as long as the shell, straight, in the basal half smooth,
cylindrical, in the distal half club-shaped, dimpled. (Very similar to Tripospyris conifera and Tripo-
spyris eucolpos, PI. 84, figs. 7 and 4 ; but the spherical shell exhibits no trace of sagittal ring or
constriction, and the simple shell-cavity has a wide open mouth, and is not closed by a basal
plate.)

Dimensions. — Shell 01 diameter, horn and feet 0'08 to 0'09 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

6. Tripilidium costatum, n. sp. (PI. 98, figs. 8, 8«, 8fe).

Shell ovate, spinulate and costate, nearly twice as broad as long. Surface with fifteen to twenty
prominent longitudinal ribs, which are convergent towards each pole and elegantly denticulate. The
deep furrows between them are divided by delicate, parallel, transverse ribs into numerous short and
broad dimples (thirty to forty in each furrow); each dimple contains a small pore, like a transverse

1142 THE VOYAGE OF H.M.S. CHALLENGER.

fissure. The apex bears a short and stout, three-sided pyramidal horn, the hollow base of which is
closed by a small cortinar septum with three collar pores (fig. 8&). This seems to indicate a
rudimentary cephalis and the derivation of this species from Lychnocanium (PI. 61). Peristome
constricted, only one-fourth as broad as the shell, with three short, conical, nearly vertical feet.
The central capsule (fig. 8«) in the specimen examined was well preserved, hemispherical, not lobate,
and filled up the upper half of the shell-cavity (beyond the rudiment of the cortinar septum).

Dimensions. — Shell 0'2 long, 012 broad ; horn O'Ol long, feet 0'02 long.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

7. Tripilidium elongatum, n. sp.

Shell elongate, smooth, nearly cylindrical, in the upper third conical. Pores small and
numerous, regular, circular, half as broad as the bars, disposed in about thirty longitudinal alternating
rows. Peristome scarcely constricted. The apical horn and the three parallel feet are of equal size
and similar form, straight, conical, one-sixth as long as the shell.

Dimensions. — Shell 012 long, 0'06 broad ; horn and feet 0'02 long.

Habitat. — Fossil in Barbados.

Subgenus 2. Tripodocorys, Haeckel, 1881, Prodromus, p. 428.
Definition. — Feet forked or branched.

8. Tripilidium dichopodiutn, n. sp.

Shell hemispherical, nearly twice as broad as long, smooth. Pores irregular, roundish, twice to
four times as broad as the bars. Mouth wide open. Apical horn spindle-shaped, half as long as
the shell. Three feet cylindrical, nearly straight and parallel, as long as the shell, forked at the
'distal end. (Exhibits an external similarity to Tripospyris semantis, PI. 84, fig. 2, but has no trace
of sagittal ring and constriction, and the simple shell-cavity has a wide open mouth.)

Dimensions. — 0'06 long, O'l broad ; horn 0'03 long, feet 0'07 long.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

9. Tripilidium cladopodium, n. sp.

Shell campanulate, rough, about as long as broad. Pores subregxilar, circular, as broad as the
bars. Mouth slightly constricted. Apical horn and three divergent feet of nearly equal size and
form, three-sided prismatic, straight • and stout, irregularly dentate and branched, somewhat longer
than the shell.

Dimensions. — Shell 0'08 diameter ; horn and feet O'l to 012 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

REPORT ON THE RADIOLARIA. 1143

Genus 502. Tripodiscium? Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) without lateral
ribs and apical horn, with three simple or branched terminal feet.

The genus Tripodiscium may be derived either from the preceding Tripilidium by
loss of the apical horn, or from .the nearly related Tristylospyris by loss of the sagittal
ring and constriction. Some forms of the latter genus can scarcely be distinguished
from similar species of the former.

Subgenus 1. Tripodiscinus, Haeckel.
Definition. — Feet simple, not branched nor forked.

1. Tripodiscium tristylospyris, n. sp.

Shell subspherical, with regular, circular pores, twice as broad as the bars. Mouth constricted,
half as broad as the shell, with three short spindle-shaped feet, which are nearly parallel and
vertical, half as long as the shell. (Similar to Tristylospyris scapkipes, PI. 84, fig. 13, but without
sagittal ring and constriction.)

Ditnensions. — Shell O08 long, O07 broad ; feet 0'04 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Tripodiscium ovatum, u. sp.

Shell ovate, rough, nearly as broad as long. Pores regular circular, double-contoured, twice
as broad as the bars. Mouth constricted, one-third as broad as the shell, with three convergent
short triangular feet.

Dimensions. — Shell 01 long, 0'09 broad ; feet 0'02 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Tripodiscium clavatum, n. sp.

Shell ovate, smooth, one and a half times as long as broad. Pores irregular roundish, of
different sizes. Mouth constricted, two-thirds as broad as the shell, with three divergent, straight
club-shaped feet, nearly as long as the shell.

Dimensions. — Shell 012 long, 0'08 broad ; feet 01 long.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

1 Tripodiicium= Shell with three small feet ; TJI«, weB<V«io».

1144 THE VOYAGE OF H.M.S. CHALLENGER.

4. Tripodiscium campanula, Haeckel.

Carpocanium campanula, Stbhr, 1880, Palaeontogr., vol. xxvi. p. 96, Taf. iii. fig. 9.

Shell campanulate or subspherical, smooth, about as long as broad. Pores small, regular
circular, as broad as the bars. Mouth constricted, about half as broad as the shell, with three short
conical descending feet.

Dimensions.— Shell 0'06 long, 0'05 broad ; feet 0'02 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms ; fossil in Sicily.

Subgenus 2. Tripodisculus, Haeckel.
Definition. — Feet branched or forked.

5. Tripodiscium furcatum, n. sp.

Shell ovate, rough, nearly as broad as long. Pores subregular, circular, twice as broad as the
bars. Mouth constricted, two-thirds as broad as the shell, with three divergent parallel and vertical
feet, which are as long as the shell, and forked at the distal end.

Dimensions. — Shell 0'09 long, 0'08 broad ; feet 0'07 long.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

6. Tripodiscium ramosum, n. sp.

Shell ovate, tuberculate, nearly as broad as long. Pores irregular, roundish, of very different
sizes. Mouth constricted, half as broad as the shell, with three large, divergent, irregularly branched
feet, nearly twice as long as the shell. (Similar to Tristylospi/ris ramosa, PI. 52, fig. 23, but without
sagittal ring and constriction.)

Dimensions. — Shell 0'07 long, 0'06 broad ; feet 015 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

7. Tripodiscium sphcerocephalum, n. sp. (PI. 52, tig. '

Shell subspherical, rough, with circular pores of different sizes. Mouth constricted, circular,
simple, two-thirds as broad as the shell, with three large divergent feet, which are three-sided
prismatic, irregularly branched, and twice as long as the shell.

Dimensions. — .Shell 0'07 long, 0'08 broad ; feet 0'12 long.

Habitat.— Central Pacific, Station 272, depth 2600 fathoms.

REPORT ON THE RADIOLARIA. 1145

Genus 503. Tridictyopus,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchipilida (vel Monocyrtida triradiata aperta) with three latticed
terminal feet. Shell ovate or subconical, with an apical horn.

The genus Tridictyopus differs from the nearly allied Tripilidium in the possession
of three large fenestrated shovel-shaped feet, forming direct prolongations of the large
conical shell. The lattice work exhibits a peculiar elegant structure recurring in the
similar, perhaps nearly related, Cephalospyris (PI. 83, fig. 10; PL 96, fig. 28). The
central capsule is large, ellipsoidal or ovate, and fills up the greater part of the .shell
cavity (compare B, Hertwig, 1879, loc. tit, p. 75),

L Tridictyopus vatillum, n. sp. (PI. 51, fig. 8).

Shell campanulate, about as long as broad (excluding horn and feet). Pores irregular,
polygonal, in the middle part more regular, triangular. Horn short and stout, three-sided
pyramidal. Three feet large, triangular, shovel-shaped, about half as long as the shell

Dimensions. — Shell 014 long, 015 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

2, Tridictyopus conulus, n. sp. (PL 51, fig. 7).

Shell campanulate conical, about one and a half times as long as broad (excluding horn and
feet). Pores mostly triangular, disposed in subregular hexagonal figures, which are separated by
bands of smaller irregular polygonal pores. Horn short and stout, three-sided pyramidal. Three
feet triangular shovel-shaped, convergent, about one-sixth as long as the shell.

Dimensions. — Shell 0'3 long, 0'2 broad ; horn 0'04 long, feet 0'05 long,

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

3. Tridictyopus elegans, R. Hertwig.

Trididyopus elegans, E. Hertwig, 1879, Organismus d. Eadiol., p. 75, Taf. vii. fig. 3, So, 3b.

Shell slender, conical, campanulate, about twice 'as long as broad (excluding horn and feet).
Most pores subregular triangular, with some irregular polygonal ones intermingled. The horn in the
two observed specimens was broken off, together with the conical apex of the shell. Three feet
triangular shovel-shaped, about one-sixth as long as the shell.

Dimensions. — Shell 0"3 long, 015 broad ; feet 0'05 long.

Habitat. — Mediterranean (Messina), E. Hertwig, surface.

1 Tridictyopus = Shell with three lattice-feet; TJ/», 8/«Tv»v, xoi/f.

(ZOOL. CHALL. EXP. — PAKT XL. — 1886.) Rr 144

1146 THE VOYAGE OF H.M.S. CHALLENGER.

Subfamily 2. AECHIPERIDA, Haeckel, 1881, p. 429.

Definition. — T ripocalpida with the basal- mouth of the shell fenestrated (vel
Monocyrtida triradiata clausa).

Genus 504. Euscenium^ n. gen.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) with a free
simple internal columella, prolonged into an apical horn. Three basal feet free, without
lateral wings.

The genus Euscenium and the three following nearly allied genera form together
the remarkable small group of Euscenida, probably one of the oldest and most primitive
of all C y r t o i d e a, and perhaps the common root of this suborder, arising directly
from the Plectoidea. The simple skeleton, is composed of four radial beams
united in one point (the cortinar centrum). Three beams are directed downwards,, and
form three divergent basal feet ; the fourth beam is directed upwards and represents an
apical horn ; its basal part is enclosed as " columella" in the cavity of the simple shell,
the lattice-work of which connects the four spines (compare above, Plectaniscus, p. 924).
In the genus Euscenium, the simplest of all, the columella is simple,, and the three feet
also simple, without wings.

S ubgenus 1 . Euscenarium, Haeckel.
Definition. — Three feet simple, not branched.

1. Euscenium plectaniscus (PI. 98, fig. 1).

Shell three-sided pyramidal, thorny, about as long as broad, with three dentate edges. Frame-
work very loose, with irregular polygonal meshes ; in the middle of each of the three triangular
sides a horizontal band of denser network. Basal plate with three very large simple collar-holes.
The apical horn and the three feet are three-sided pyramidal, about half as long as the columella,
with three prominent irregularly dentate edges. The horn is straight, whilst the three feet are
hook-shaped, its distal end being curved downwards and inwards..

Dimensions. — Shell Oil long, 013 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms,

2. Euscenium archicyrtis, n. sp.

Shell three-sided pyramidal, smooth, nearly as long as broad, with three straight edges
connected by irregular loose framework with polygonal meshes. Basal plate with three very large

1 Euscenium = Nice small tent ; sv awt/iM.

REPORT ON THE RADIOLARIA. 1147

simple collar-holes. The apical horn and the three feet are three-sided prismatic, smooth, about
twice as long as the columella, straight and widely divergent.

Dimensions. — Shell O08 long, 01 broad.

Habitat. — Tropical Pacific, Station 225, depth 4475 fathoms.

3. Euscenium hemisphcericum, n. sp.

Shell hemispherical smooth, half as long as broad, with small and numerous subregular circular
pores. Basal plate with three large triangular simple collar-holes. Horn slender, three-sided
prismatic, twice as long as the columella. Feet very slender, with three denticulate edges, widely
divergent and curved like the quadrant of a circle.

Dimensions. — Shell 0'04 long, 0'06 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Euscenium tricolpium, n. sp. (PL 53, fig. 12).

Archiscenium tricolpium, Haeckel, 1881, Prodromus et Atlas, loc. cit.

Shell cap-shaped, nearly hemispherical, with three vaulted hemispherical bosoms between the
three arches ascending from the feet to the horn. Network very irregular, with polygonal meshes,
of different form and size. Basal plate with three large primary and some smaller irregular
accessory collar-holes. Horn slender, straight, twice as long as the columella. Feet of the same
length, slender, widely divergent, slightly curved. The three edges of the horn and the feet are
elegantly denticulated.

Dimensions. — Shell 0*04 long, 0'08 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

5. Euscenium tripospyris, n. sp. (PL 84, fig. 8).

Tripospyris euscenium, Haeckel, 1881, Prodromus et Atlas.

Shell nearly spherical, smooth, with numerous small circular pores. Basal plate also with
numerous small pores. Horn and feet stout, three-sided prismatic, straight or slightly curved, about
as long as the thin, somewhat curved columella. This species is closely allied to Tripospyris.

Dimensions. — Shell Oil to 012 diameter, horn and feet 0'08 to 01 long.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

Subgenus 2. Euscenidium, Haeckel.
Definition — Feet forked or branched.

6. Euscenium furcatum, n. sp.

Shell campanulate, smooth, with numerous irregular roundish pores. Basal plate with nine
pores (three larger central and six smaller distal). Horn club-shaped, half as long as the columella.

1148 THE VOYAGE OF H.M.S. CHALLENGER.

Feet twice as long, cylindrical, parallel, vertical, forked at the distal end. (Similar to Tvipospyris
semantis, PL 84, fig. 2, but without sagittal feet.)

Dimensions. — Shell 0'07 long, 0'06 broad; horn 0'04 long, feet 01 long,

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

7. Euscenium quadratum, n. sp.

Shell campanulate, smooth, with subregular square pores. Basal plate with three large pores.
Horn and feet of the same size and shape, twice as long as the columella, three-sided prismatic,
each with four or five verticils of lateral branches. (Similar to the cephalis of Clathrocorys murrayi,
PL 64, fig. 8, but with four free spines without connecting lattice-wings.)

Dimensions. — Shell 0'06 long, 0'05 broad ; horn and feet 012 long.

Habitat. — Central Pacific, Station 272, surface.

-•

8. Euscenium ramosum^ n. sp.

Shell subspherical, rough, with small subregular circular pores. Basal plate with nine pores (three
larger central and six smaller distal pores). Horn and feet of the same size and form, three to four
times as long as the columella, three-sided prismatic, irregularly branched.

Dimensions. — Shell 0'06 diameter, horn and feet 015 to 0'2 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 505. Cladoscenium,1 Haeckel, 1881, Prodromus, p. 429.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) with a free
branched internal columella, prolonged into an apical horn. Three basal feet free,
without lateral wings.

The genus Cladoscenium differs from the preceding Euscenium only in the ramifica-
tion of the internal columella, which bears one or more verticils of three ascending
lateral branches. The three branches of each verticil lie in the same equidistant
meridian planes as the three basal feet, and are inserted with their distal ends on the
inner surface of the simple lattice-shell. The three feet are also branched, but without
vertical lattice-wings. Cladoscenium is perhaps closely allied to Clathrocorys.

1. Cladoscenium fulcratum, n. sp.

Shell subspherical, smooth, with large irregular roundish pores. Basal plate with three large pores.
Columella with a single verticil of three ascending lateral branches. Apical horn as long as the

1 Cladoscenium— Small tent with, branched axis ;

REPORT ON THE RADIOLARIA. 1149

columella, simple, three-sided prismatic. Feet twice as long, widely divergent, straight, prismatic,
with some irregular basal branches.

Dimensions. — Shell O06 diameter, horn O'Oo long, feet 01 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Cladoscenium ancoratum, n. sp. (PI. 53, fig. 13).

Shell campanulate, smooth, with irregular polygonal pores. Basal plate with six pores (two
large cardinal, two smaller jugular and two still smaller cervical pores). Columella with a single
verticil of three ascending lateral branches (by mistake not distinct in the figure). Apical horn
and the three feet of the same form and size, slender, prismatic, twice to three times as long as the
shell, straight, in the distal half with three slender recurved branches, anchor-shaped.

Dimensions. — Shell 0'05 long, 0'04 broad ; horn and feet 01 to 015 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Cladoscenium gladiatum, n. sp.

Shell subspherical, with irregular polygonal pores. Basal plate with three large pores.
Columella with two verticils of three ascending lateral branches. Apical horn as long as the
columella, three-sided prismatic. Feet of the same form, twice as long, in the distal half with two
opposite transverse branches, sword-shaped.

Dimensions. — Shell O'Oo long, 0'06 broad ; horn 0'04 long, feet 01 long.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

4. Cladoscenium pinnatum, n. sp.

Shell campanulate, with irregular polygonal pores. Basal plate with four pores (two major
cardinal and two minor jugular). Columella with two verticils of three ascending lateral branches,
and prolonged into a slender prismatic apical horn of twice the length, which bears four such
verticils. Feet twice as long as the horn, pinnate, each with four or five pairs of opposite lateral
branches, decreasing towards the thin distal end.

Dimensions. — Shell 0'06 long, 0'05 broad ; horn 01 long, feet 0'2 long.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

5. Cladoscenium verticillatum, n. sp.

Shell campanulate, with subregular square pores. Basal plate with nine pores (three larger
central and six smaller distal). Columella with three verticils of three ascending lateral branches.
Apical horn and the three basal feet of equal size and similar form, four to six times as long as the
columella, three-sided prismatic, each with four to five verticils of three lateral branches, which are

1150 THE VOYAGE OF H.M.S. CHALLENGER.

irregularly ramified and tapering towards the distal end. (Similar to Clathrocorys teuscheri, PL 64,
fig. 10, but with four free spines, without connecting lattice- wings.)

Dimensions. — Shell 0'07 long, O06 broad ; horn and feet 0'2 to 0'25 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

6. Cladoscenium pectinatum, n. sp. (PI. 98, fig. 2).

Shell subspherical, with irregular roundish pores. Basal plate with three large holes.
Oolumella with two verticils of three ascending lateral branches. Apical horn and the three feet
of nearly the same size and form, three to four times as long as the columella, straight, three-
sided prismatic, each with five to eight verticils of three simple lateral branches, tapering towards
the distal end.

Dimensions. — Shell 0'07 long, 0'08 broad ; horn and feet 016 to 0'22 long.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 506. Archiscenium? HaeckeL, 1881, Prodromus, p. 429.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) with a free
simple internal columella, prolonged into an apical horn. Three basal feet connected
with the horn by three vertical lateral wings.

The genus Archiscenium and the following nearly allied Pteroscenium are derived
from the two preceding genera, from which they differ in the development of three free
vertical lateral lattice-wings ; these arise from the upper edge of the three basal feet
and connect them with the three edges of the apical horn. The basal part of the latter,
enclosed in the shell, forms an internal free columella, which in Archiscenium is simple,
not branched.

1. Archiscenium quadrispinum, n. sp. (PI. 53, fig. 11).

Shell hemispherical, smooth, with a small number of large irregular polygonal meshes and thin
bars. Basal lattice with three very large central meshes and six smaller peripheral meshes (two on
the base of each foot). Apical horn and the three feet of equal size and similar form, slender,
pyramidal, widely divergent, straight, as long as the shell-diameter. Three lateral wings small,
little prominent, each with two or three irregular meshes. Central capsule subspherical.

Dimensions. — Shell 0'05 long, 01 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

2. Archiscenium clathrocorys, n. sp.

Shell campanulate, smooth, with numerous irregular square meshes. Basal lattice with three very
large meshes. Apical horn and the three feet of equal size and similar form, three-sided prismatic,

1 A rchiscenium = Primordial tent ;

REPORT ON THE RADIOLARIA. 1151

widely divergent, straight, twice as long as the shell-diameter. Three lateral wings broad, each
with a basal row of few very large irregular roundish meshes, and several distal rows of small
square meshes. This species is very similar to Clathrocorys murrayi (PI. 64, fig. 8), but has no
trace of thorax-wall. The latter species may be derived from the former by development of the
thoracic lattice, which connects the three free feet.

Dimensions. — Shell 005 long, 0'06 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Archiscenium tripterygium, n. sp.

Shell hemispherical, smooth, with numerous irregular roundish meshes of very different sizes.
Basal lattice with four large meshes, two major cardinal and two minor cardinal pores. Apical
horn and the three feet of similar form and size, slender prismatic, three to four times as long as
the shell ; the horn straight, the feet curved. Three lateral wings very delicate, with a basal row
of few large irregular polygonal meshes, and several distar rows of similar small pores.

Dimensions. — Shell 0'04 long, 0'05 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Archiscenium cyclopterum, n. sp. (PI. 98, fig. 3).

Shell hemispherical, with small irregular roundish pores. Basal lattice with four large meshes,
two major cardinal and two minor jugular pores. Apical horn and the three feet of similar form
and size, slender prismatic, straight, twice to four times as long as the shell. Three lateral wings
nearly semicircular, densely latticed, with the same pores as the shell, and smooth convex margin.

Dimensions. — Shell 0'05 long, 0'06 broad.

Habitat. — South Pacific, Station 295, depth 1500- fathoms.

5. Archiscenium callimitra, n. sp.

Shell campanulate, with irregular polygonal pores. Basal lattice with nine meshes- (three larger
central and six smaller distal pores, as in Callimitra carolotce, PI. 63, fig. 8). Apical horn straight,
prismatic, slender, conical, twice as long as the shell. Feet longer and more slender, slightly
curved. Three lateral wings very broad, densely fenestrated, with irregular polygonal pores of the
same shape as in the similar Callimitra carolotce (PI. 63, fig. 1).

Dimensions. — Shell 0-05 long, 0-04 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Genus 507. Pteroscenium,1 Haeckel, 1881, Prodromus, p. 429.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) with a free
branched internal columella, prolonged into an apical horn. Three basal feet connected
with the horn by three vertical lateral wings.

1 Pteroscenium = Small tent with wings ; srrejo'i/, aann'ov.

1152 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Pteroscenium differs from the preceding Archiscenium only in the
ramification of the internal columella, and therefore exhibits to it the same relation
that Cladoscenium bears to Euscenium. The branches of the columella form also here
verticils of ascending branches, three in each verticil, and their distal ends are inserted
on the inner surface of the lattice-shell.

1. Pteroscenium arcuatum, n. sp. (PI. 98, fig. 4).

Shell campanulate, smooth, nearly conical, somewhat broader than long, with irregular dense
network of small circular pores. Columella straight, with two or three triradiate verticils of
horizontal lateral branches, which are inserted in the shell- wall. Horn slender pyramidal, as long as
the shell. Three divergent feet twice as long as the horn, strongly curved, thorny, three-edged ; the
distance of their pointed ends twice as broad as the shell. From the outer edge of each foot arise
numerous ascending bristles, which are connected together and with similar lateral branches of the
horn by curved arches, forming three delicate spiny vertical wings.

Dimensions. — Shell 0'06 long, 0'08 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Pteroscenium arcadophorum, n. sp.

Shell campanulate, smooth, with irregular polygonal pores, very similar to the preceding species
but with much broader wings, forming several arcades with three to five rows of irregular meshes.
Columella with five or six triradiate verticils of lateral branches. Horn twice as long as the shell,
of the same length as the strongly curved spinulate feet.

Dimensions. — Shell 0'09 long, OH broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Pteroscenium pinnatum, n. sp. (PI. 53, figs. 14, 15, 16).

Shell eampanulate, smooth, somewhat longer than broad, with irregular delicate network of
small roundish pores. Columella straight, with numerous (eight to twelve) triradiate verticils of
ascending lateral branches, which are inserted in the shell-wall. The uppermost end of the
columella is a conical apical horn. The three divergent feet are smooth, slender, conical, slightly
curved, about as long as the shell, pinnate, with six to ten pairs of ascending lateral branches,
parallel to those of the columella and inserted on the three vaulted lateral wings. (Fig. 14 exhibits
the outside of the shell, fig. 15 the internal structure of the cortina, fig. 16 the basal view.)

Dimensions. — Shell O'l long, 0'12 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

4. Pteroscenium spinulosum, n. sp.

Shell campanulate, spinulate, about as long as broad, with small and numerous irregular
polygonal pores, very similar to the preceding species, but differing in the more slender form of

REPORT ON THE RADIOLARIA. 1153

the horn and the feet, bearing more numerous lateral branches (twelve .to sixteen pairs on each
foot). Columella with six to eight triradiate verticils. Horn about as long as the shell.

Dimensions. — Shell O'l long, O'l broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

5. Pteroscenium macropodium, n. sp.

Shell campanulate, spinulate, with irregular polygonal pores ; very similar to the two preceding
species, but differing in the size and shape of the three feet, which are for the most part solid,
triangular, nearly parallel, vertical, very slender, three times as long as the shell, latticed only at
the curved base, with few ,pairs of lateral branches. Columella with four to six triradiate verticils,
as long as the stout triangular pyramidal horn.

Dimensions. — Shell 01 long, 0'08 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Pteroscenium tripocolpum, n. sp.

Shell campannlate, spinulate, similar to Euscenium tricolpium (PI. .53, fig. 12) with three vaulted
hemispherical bosoms between the three delicate arachnoidal vertical wings. Network loose, very
irregular, with polygonal meshes of very different sizes. Columella with three or four triradiate
verticils, as long as the slender pyramidal horn. Three feet twice as long, somewhat curved, widely
divergent, with three or four pairs of lateral branches. The three edges of the feet and of the horn
are elegantly denticulated.

Dimensions. — Shell 0'06 long, 0'09 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 508. Peridium,1 HaeckeL 1881, p. 429.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) without internal
columella, with an apical horn.

The genus Peridium (or Archiperidium, Prodromus, loc. cit.) and the ,two following
nearly allied genera form together the small group of Archibursida, differing from the
four preceding genera (the Euscenida) in the absence of an internal free columella.
The three basal feet have therefore no direct connection with the apical horn.
Peridium, the ancestral form of the Archibursida, may have originated either from
Euscenium by reduction and loss of the columella, or directly from Tripospyris by loss
of the sagittal ring and the longitudinal constriction.

Subgenus 1. Peridarium, Haeckel.
Definition. — Feet smooth, simple, neither spiny nor branched.

1 Peridium — Small pouch ; ifn^iot.
(ZOOL. CHALL. BXP. — PART XL. — 1886.) Rr 145

1154 THE VOYAGE OF H.M.S. CHALLENGER.

1. Peridium lasanum, n. sp.

Shell subspherical, smooth, with subregular circular pores. Basal plate with three large meshes.
Horn apical, vertical, of the same size and form as the three divergent smooth feet, slender pyra-
midal, twice to three times as long as the shell.

Dimensions. — Shell-diameter 0'06 to O07, length of the three spines 015 to 0'2.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

2. Peridium papillatum, n. sp.

Shell subspherical, papillate, with subregular circular pores. Basal plate with four meshes
(two major cardinal and two minor jugular pores). Horn occipital, oblique, three-sided pyramidal,
half as long as the shell and as the three widely divergent, subhorizontal, smooth feet.

Dimensions. — Shell diameter O'OY to 0'08, length of the horn 0'04, of the feet 0'08.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Peridium curvipes, n. sp.

Shell hemispherical, thorny, with irregular roundish pores. Basal plate with six pores (two
larger middle cardinal, two smaller anterior jugular and two smaller posterior cervical pores, as in
PI. 53, figs. 13, 18). Horn conical, oblique, arising from the middle of the occipital face, half as
long as the shell. Feet slender, conical, curved, smooth, twice as long as the shell.

Dimensions. — Shell 0'04 long, 0'06 broad ; horn 0'02 long; feet 0'08 long.

Habitat. — Tropical Pacific, Station 206, depth 2100 fathoms.

Subgenus 2. Archiperidium, Haeckel.
Definition. — Feet spiny or branched.

4. Peridium spinipes, n. sp. (PI. 53, fig. 9).

Shell ovate, rough or thorny, with irregular roundish pores. Basal plate with four pores (two
larger cardinal and two smaller jugular pores). Horn oblique, occipital, three-sided pyramidal, half
as long as the shell, connected with the caudal foot by a prominent crest. Three feet horizontally
expanded, prismatic, spiny, about as long as the shell.

Dimensions. — Shell 0'08 long, 0'06 broad ; horn 0'04 long, feet 0'06 to 0'09 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

5. Peridium palmipes, n. sp. (PI. 53, fig. 10).

Shell ovate, smooth, with irregular roundish pores. Basal plate with three large pores. Horn
oblique, three-sided pyramidal, about as long as the shell, inserted near its occipital base. Three
feet prismatic, slender, half as long, ending with a broad dentate plate.

Dimensions. — Shell 0'06 long, 0'05 broad ; horn 0'05 long, feet 0'03 long.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

REPORT ON THE RADIOLARIA. 1155

6. Peridium alatum, n. sp. (PL 97, fig. 7).

Shell subspherical smooth, with regular circular, hexagonally-framed pores. Basal plate with nine
pores (three larger central and six smaller distal pores). Horn apical, of equal size and the same form
as the three feet, three-sided prismatic, with three broad prominent wings, somewhat longer than the
shell.

Dimensions. — Shell 0-Q7 long, 0'08 broad ; horn and feet 01 to 012 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

f

7. Peridium cervinum, n. sp.

Shell subspherical, spiny, with subregular circular pores. Basal plate with four pores (?).
Horn apical, conical, about as long as the shell. Feet three to four times as long, cylindrical
curved, with irregular simple or forked branches like the antlers of a deer.

Dimensions. — Shell diameter 01, horn 01 long, feet 0'3 to 0-4 long.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 509. Archipera,1 Haeckel, 1881, Prodromus, p. 429.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) without internal
columella, with two or more apical horns.

The genus Archipera differs from the preceding Peridium only in the multiplication
of the apical horn, which in the latter is always simple. The number of horns is
usually two or three, sometimes four or more. The species bearing three horns may be
derived directly from Triceraspyris by loss of the sagittal ring.

1. Archipera cortiniscus, n. sp. (PI. 98, fig. 5).

Shell ovate, thorny, with large roundish pores, which are closed by sieve-plates with numerous
small porules. Basal plate with two pairs of simple large pores (two smaller jugular and two
larger cardinal, similar to PL 98, fig. 10J). Two horns divergent, curved, slender, pyramidal ; the
apical horn longer than the shell, the frontal horn shorter. Three feet divergent, longer than the
shell, three-sided prismatic, at the distal end club-shaped, thorny.

Dimensions. — Shell 01 long, 0'08 broad ; horns and feet Oil to 014 long.

Habitat. — Tropical Pacific, Station 225, depth 4475 fathoms.

2. Archipera pentacantha, n. sp.

Shell pear-shaped, smooth, with numerous and small irregular roundish pores. Basal plate with
three larger pores. Two horns and three feet of nearly equal size and similar form, three-sided

1 Archipera = Primordial pouch ; a?x'> »«ig*.

1156 THE VOYAGE OF H.M.S. CHALLENGER.

prismatic, about as long as the shell diameter, somewhat curved. The apical horn stands on the
apex, the frontal horn half-way up the shell.

Dimensions. — Shell 0*08 long, O06 broad; horns and feet 0'05 to 0-07 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Archipera bicornis, n. sp.

Shell ovate, rough, with small regular circular, sparsely scattered pores. Basal plate with four
larger central and a peripheral coronal of twelve smaller pores. Two horns near the apex widely
divergent, somewhat shorter than the shell, of equal size and similar form. Three feet twice as
long, horizontally expanded. All five spines slender, three-sided pyramidal, straight.

Dimensions. — Shell 0-07 long, 0'06 broad ; horns 0'05 long, feet 01 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Archipera tricornis, n. sp.

Shell subspherical, smooth, with subregular circular pores. Basal plate with four large meshes
(two major cardinal and two minor jugular pores). On the apex three divergent pyramidal horns
of different size, one larger occipital and two smaller frontal horns. Three feet prismatic, about
twice as long as the shell.

Dimensions. — Shell diameter 0'05, length of the feet 01.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

5. Archipera quadricornis, n. sp.

Shell ovate, smooth, with a small number of irregular roundish, widely scattered pores;
Basal plate with four crossed meshes of nearly equal size. On the equator there arise four divergent
prismatic horns of nearly equal size, three of which correspond to the three feet, whilst the fourth is
opposite to the caudal foot. The three feet are also prismatic, as long as the shell, horizontally
expanded. (Similar to the upper half of Lithomelissa decacantha, PI. 56, fig. 2, but without thorax.)

Dimensions. — Shell 0'05 long, 0'04 broad ; horns and feet 0'06 long.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

6. Archipera multicornis, n. sp.

Shell hemispherical, spiny, with irregular polygonal pores. Basal plate with six meshes (?).
Between the smaller spines of the surface arise six larger conical divergent horns. Three feet also
conical, divergent, about twice as long as the shell and the horns.

Dimensions. — Shell 0'05 long, 0'07 broad ; horns 0'05 long, feet 01 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

REPORT ON THE RADIOLARIA. 1157

Genus 510. Archibursa,1 Haeckel, 1881, Prodromus, p. 429.

Definition. — A rchiperida (vel Monocyrtida triradiata clausa) without internal
columella and without apical horn.

The genus Archibursa has probably arisen from Peridium by loss of the apical
horn, and is the only genus of Archiperida which bears no horn. The three basal feet
are well-developed. It differs from the similar Tristylospyris by the absence of the
sagittal ring and the corresponding longitudinal constriction.

1. Archibursa tripodiscus, n. sp. (PI. 98,. fig. 6).

Shell subspherical, smooth, with irregular roundish pores. Basal plate with Miree large
triangular pores of equal size (fig. 6). Three feet widely divergent, straight, three-sided prismatic,
about as long as the diameter of the shell.

Dimensions. — Diameter of the shell 0'07,. length of the feet 0'09..

Habitat.- — Central Pacific, Station 272, depth 2600 fathoms.

Family LX. PH^NOCALPIDA, n. fam,

Arcliiphormida et Archiphcenida, Haeckel, 1881, Prodromus, pp. 428, 429.

Definition. — M onocyrtida multiradiata. (Cyrtoidea with a simple, not
jointed shell, resembling a simple cephalis, with numerous radial apophyses (four to nine
or more).

The family Phsenocalpida, composed of the Archiphormida and Archiphsenida of
my Prodromus, comprises those Cyrtoidea in which the lattice-shell is quite without
transverse constriction, but bears numerous radial apophyses. The two subfamilies
differ in the shape of the basal mouth, which in the Archiphormida is a simple wide
opening, but is closed in the Archiphsenida by a lattice -plate.

Several Phsenocalpida were formerly described by Ehrenberg, viz., Halicalyptra
virginica (in 1844) and Litharachnium arachnodiscus (in 1872, called by him
Carpocanium, though it is quite different from this genus, and closely allied to my
Litharachnium tentorium, figured in 1862). These forms belong to the Archiphormida
(with open mouth). Several fossil Archiphsenida (with closed mouth) were figured by
Ehrenberg, in 1875, as belonging to Petalospyris (ocellata, carinata, flabellum}, though
the absence of the sagittal ring and the corresponding longitudinal constriction
demonstrates their character as Phcenocalpis.

1 Archibursa = Primordial bottle ;

1158

THE VOYAGE OF H.M.S. CHALLENGER.

The Phsenocalpida are probably an artificial family, composed of three or four (or
perhaps more) different groups, which have a quite different origin. The Litharachnida
(genera 511—515) and the Haliphonnida (genera 516—518) are probably derived from
the Sethophormida by loss of the cephalis, the retrograde metamorphosis of which
may be observed in all its different stages. The Halicalyptrida (genera 519-521) are
perhaps independent of the other Phsenocalpida, and may be Archicorida which have
produced a corona of teeth around the mouth, without relation to lost radial ribs. The
Phsenoscenida (Phcenocalpis, Phcenoscenium) may be derived from the Euscenida
(genera 504—507) by interpolation of interradial feet between the three primary ones, or
directly from the P 1 e c t o i d e a. The Calpophsenida, on the other hand (Calpophcena,
Archiphcena], may have arisen from the Zygospyrida (Petalospyris, Gorgospyris] by
loss of the sagittal ring and the longitudinal constriction. The phylogeny of the
Phsenocalpida is therefore a very complicated problem, as yet unsolved.

Synopsis of the Genera of Phsenocalpida.

I. Subfamily

Archiphormida.
Basal mouth of the •
shell a simple wide
opening.

Shell simple, with simple net-
work,

Shell slender,
pyramidal <
(without horn).

Shell simple, with double
network,

Radial ribs
enclosed in •
the wall of

Shell double, with an outer
mantle, .

the shell,
usually pro-
longed into
free terminal

Shell flatly
, , ' Kadial ribs simple, .
campanulate or !

oiscoitlcil ( "with- 1
j i \ 1 it^diSil ri uy DrciiicliGCi.

feet.

Shell ovate,
urceolate or -
campanulate.

Mouth smooth, constricted
(no horn),

Mouth with ( With horn,
a corona of <

feet. ( No horn,

No radial ribs in the wall of

' Shell simple ( With horn, .
without <

the shell. Mouth surround-
ed by a corona of free ter-
minal feet.

mantle. ( No horn, .

Shell double, with an exter-
nal mantle (no horn),

II. Subfamily

Archiphaenida.
Basal mouth closed by
a lattice-plate.

In the axis of the shell-cavity ( Columella simPle> •

a free columella.

[ Columella branched,

Shell-cavity simple, without f APex ^th a horn'
axial columella. {-No apical horn,

511. Bathropyraims.

512. Cindopyramis.

513. Peripyramis.

514. Litharachnium.

515. Cladarachnium.

516. Cyrtophormis.

517. Haliphorniis.

518. Arcliiphormiis.

519. Halicalyptra.

520. Carpocanistrum.

521. Arachnocalpis.

522. Phcenocalpis.

523. Phcenoscenium.

524. CalpophcKna.

525. Archiplicena.

REPORT ON THE RADIOLARIA. 1159

Subfamily 1. AKCHIPHORMIDA, Haeckel, 1881, Prodromus, p. 428.

Definition. — P hsenocalpida with the basal mouth of the shell open (vel
Monocyrtida multiradiata aperta).

Genus 511. Bathropyramis,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — Ar chiph ormida (vel Monocyrtida multiradiata aperta) with
simple, slender pyramidal shell and numerous radial beams (six to nine or more).
Network simple, with large, unfenestrated, quadrangular meshes.

The genus Bathropyramis and the following four nearly allied genera form together
a peculiar group of Archiphormida, the Litharachnida, possessing near relations to
Sethopyramis and the allied Sethophormida, from which they are probably derived by
reduction and loss of the small cephalis. The shell in all these forms is distinctly
pyramidal, composed of numerous divergent radial beams (commonly six to nine),
which form the edges of the pyramid,, and are connected by parallel horizontal rings.
The quadrangular meshes so produced are quite simple in Bathropyramis. This genus
cannot be sharply separated from Sethopyramis, its ancestral form.

Subgenus 1. Acropyramis, Haeckel, 1881, Prodromus, p. 428.
Definition. — Shell smooth, without spines on the surface.

1. Bathropyramis acephala, n. sp.

Shell smooth, slenderly pyramidal, with three cortinar pores at the apex and with six stout radial
beams or longitudinal ribs, connected by twelve to sixteen complete hexagonal horizontal rings.
Meshes nearly square, increasing gradually in size towards the mouth.

Dimensions. — Shell 0-25 long, 0'15 broad.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

2. Bathropyramis quadrata, n. sp. (PI. 54, fig. 1).

Shell smooth, slenderly pyramidal, with three cortinar pores at the apex and nine stout radial
beams, connected by eight to twelve complete circular horizontal rings. Meshes subregular, square,
increasing on size gradually towards the circular mouth.

Dimensions. — Shell 0'2 to 0'3 long, 012 to 0'2 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.
1 Bathropyramis = Pyramid with ladders ;

1160 THE VOYAGE OF H.M.S. CHALLENGER.

3. Bathropyramis trapezoides, <n. sp. (PL 54, fig. 3).

Shell smooth, broadly pyramidal, with four «ortinar pores at the apex and eight (or sometimes
nine) stout radial beams, connected by twelve to sixteen complete octagonal horizontal rings.
Meshes trapezoidal, of nearly equal length, but gradually increasing in breadth.

Dimensions. — Shell 0'3 long, 03 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Bathropyramis interrupta, n. sp. (PI. 55, fig. 7).

Shell smooth, flatly pyramidal, nearly discoidal, with four cortinar pores .at the apex and nine to
ten stout radial beams, connected by eight to sixteen interrupted rings ; the rings are complete only
in the apical part, in the distal part more or less irregularly interrupted.

Dimensions. — Shell 012 long, 0'36 broad.

Habitat. — North Atlantic, Station 354, surface.

5. Bathropyramis medusa, n. sp.

Shell smooth, flatly pyramidal, nearly discoidal, with four cortinar pores and numerous radial
beams (thirty to fifty) ; the four perradial of these are prolongations of the four cortinar beams, and
alternate with four interradial of the same size. Between these are intercalated eight adradial
beams arising from the third ring ; and between the former and the latter, sixteen to twenty-four
peripheral radial beams, arising from the fourth to the sixth ring. The inner four to six rings
are complete, the outer ten to fifteen irregularly interrupted.

Dimensions. — Shell 0'08 long, 0'3 to 0'4 broad.

Habitat. — South Atlantic, Station 338, surface.

Subgenus 2. Cladopyramis, Haeckel, 1881, Prodromus, p. 428.
Definition. — Shell spiny, with prominent simple or branched spines on the surface.

6. Bathropyramis spinosa, n. sp.

Shell spiny, slenderly pyramidal, with three cortinar pores at the apex and with nine strong
radial beams, connected by fifteen to twenty complete parallel rings. Meshes subregular square,
increasing gradually in size. Surface covered with simple, strong conical spines, arising from the
nodal points.

Dimensions. — Shell 0'24 long, 016 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

REPORT ON THE RADIOLARIJL 1161

7. Bathropyramis ramosa, n. sp. (PL 54, fig. 4).

Shell spiny, slenderly pyramidal, with three cortinar pores at the apex, and with nine (or some-
times eight or ten) strong radial beams, connected by fifteen to eighteen complete parallel rings.
Meshes subregular, square, increasing gradually in size. Surface covered with forked or
irregularly branched spines, arising from the nodal points.

Dimensions. — Shell 0'3 long, 017 broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 512. Cindopyramis,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) with
simple, slender, pyramidal shell, and numerous radial beams (six to nine or more).
Network double, with a delicate arachnoidal fenestration, filling up the large quadr-
angular meshes.

/

The genus Cindopyramis differs from the preceding Bathropyramis in the
development of a very delicate secondary network, filling up the large quadrangular
meshes, which are produced by the crossing of the radial beams and the parallel
horizontal rings. It therefore bears the same relation to the preceding genus that
Plectopyramis does to Sethopyramis ; it is perhaps derived directly from the former
by loss of the small cephalis.

1. Cindopyramis cribellum, n. sp.

Cindopyramis cribellum = " Ladder of lattice-shape," Bury, 1862, Polycystins of Barbados, pi. xii.
fig. 6.

Shell slender, pyramidal, with six strong radial ribs, which are connected by twelve to sixteen
complete horizontal rings. Meshes trapezoidal, filled up by a very delicate and regular secondary
network with square porules (two to four horizontal threads in each larger mesh).

Dimensions. — Shell 0'2 to 0'3 long, 012 to 016 broad.

Habitat. — Fossil in Barbados.

2. Cindopyramis infundibulum, n. sp. (PI. 54, fig. 7).

Shell slender, pyramidal, with nine strong radial ribs, which are connected by eighteen to
twenty-four complete horizontal rings. Meshes subregular square, filled up by a very delicate and
regular secondary network with square porules (ten to twelve horizontal threads in each larger
mesh). Apex of the pyramid with three very small cortinar pores.

Dimensions. — Shell 0'3 to 0'4 long, 0'2 to 0'25 broad.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

1 Cindopyramis = Lattice-pyramid ; xiyxhis, •zv^ctfti's-

(ZOOL. CHALL. EXP. — PART XL. 1886.) Kr 146

1162 THE VOYAGE OF H.M.S. CHALLENGER.

3. Cinclopyramis lithosestrum, n. sp.

Shell slender, pyramidal, with twelve strong radial ribs (six primary longer and six secondary
shorter) connected by twelve to fifteen interrupted irregular rings. Meshes irregular square or
trapezoidal, filled up by a delicate secondary network with irregular polygonal porules.

Dimensions. — Shell 0'4 to 0'5 long, 0-2 to 0'3 broad.

Habitat. — Fossil in Barbados.

Genus 513. Peripyramis,1 Haeckel, 1881, Prodromus, p. 428.

Definition. — Ar chiph ormida (vel Monocyrtida multiradiata aperta) with
double, slenderly pyramidal shell, and numerous radial beams (six to nine or more).
Network double, with an external arachnoidal or spongy envelope around the primary
lattice-shell.

The genus Peripyramis differs from its probable ancestral form, Bathropyramis, by
development of a delicate external envelope around the primary shell, and therefore
bears to it the same relation that Spongopyramis among the Dicyrtida does to
Sethopyramis. It may also be derived directly from the former by loss of the cephalis.

1. Peripyramis circumtexta,, n. sp. (PI. 54, fig. 5).

Shell slender, pyramidal, with nine strong radial beams, connected by fifteen to twenty trans-
verse horizontal rings, which are partly complete, partly interrupted. Meshes subregular, square.
From the nodal points of the surface there arise branched spines, which at equal distances from
it are connected by thin threads, forming a delicate outer arachnoidal shell with Jarge irregular
polygonal meshes.

Dimensions. — Shell 0'32 long, 016 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Peripyramis spongiosa, n. sp.

Shell slender, pyramidal, with nine strong radial beams, connected by twelve to eighteen
irregular interrupted rings. Meshes irregular, square or polygonal. From the whole surface arise
numerous branched spines, which by communication and dense ramification form an outer spongy-
envelope around the shell. (Similar to Spontj&pyramis spongiosa, PL 56, fig. 10.)

Dimensions. — Shell 045 long, 0'32 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

1 Peripyramis = Pyramid with an envelope; ict^'i, irvea.pl;.

KEPORT ON THE RADIOLARIA. 1163

Genus 514. Litharachnium,1 Haeckel, 1860, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 835.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) with flatly
conical, tent-shaped or nearly discoidal shell, and numerous, simple, radial beams in its
wall.

The genus Litharachnium, and the closely allied genus Cladarachnium, differ from
the preceding similar genera mainly in the flat form of the depressed shell, which is not
slenderly pyramidal, but more tent-shaped or nearly discoidal. The radial ribs are
generally not straight, but more or less curved. The top of the tent exhibits three or
four important meshes, the original pores of the cortinar septum. Litharachnium may
be derived directly from Sethophormis by reduction and loss of the cephalis.

Subgsnus 1. Litharachnidium, Haeckel.

Definition. — Apex with three cortinar pores (one odd sternal and two paired cardinal
pores).

1. Litharachnium tentorium, Haeckel.

Litharacknium tentorium, Haeckel, 1862, Monogr. d. Radio!, p. 281, Taf. iv. figs. 7-10.

Shell flatly conical or tent-shaped, with concave lateral outlines. Apex with three equal
cortinar pores. Twenty radial ribs at nearly equal distances. Between them very numerous and
thin secondary ribs, crossed by more than one hundred concentric rings. Pores square, as in all
the following species. Margin truncate, circular.

Dimensions. — Shell 0'35 long, 0'8 broad.

Habitat. — Mediterranean (Messina).

2. Litharachnium araneosum (PI. 55, figs. 8, 10).

Shell flatly conical, nearly discoidal, with straight lateral outlines. Apex with three unequal
cortinar pores (one odd smaller sternal and two paired larger cardinal pores). Twenty radial ribs
at unequal distances, with numerous intercalated secondary ribs. Margin ciliate.

Dimensions. — Shell 018 long, 0'32 broad.

Habitat. — Central Pacific, Station 271, surface.

1 Litharachnium = Spider- web of silex ; Xitfoj,

1164 THE VOYAGE OF H.M.S. CHALLENGER.

3. Litharachnium arachnodiscus, Haeckel.

Litharachnium arachnodiscus, Haeckel, 1862, Monogr. d. Badiol., p. 283,

Carpocanium arachnodiscus, EErenberg, 1861, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 296 ; Abhandl. d. k. Akad. d. Wiss. Berlin, 1872, Taf. ii. fig. 8.

Shell flatly campanulate, nearly discoidal, with convex (?) lateral outlines. Apex with three
unequal cortinal pores. Nine stronger radial primary ribs complete; between them numerous
secondary intercalated ribs (sixty to seventy). Margin ciliate.

Dimensions. — Shell O03 long, 01 broad (?).

Habitat. — Arctic Ocean (between Greenland and Iceland), depth 1000 fathoms (Schaffner),.

4. Litharachnium epeira, n. sp. (PL 55, fig. 9).

Shell flatly conical or tent-shaped, with concave lateral outlines. Apex with three unequal
cortinar pores. Twelve stronger radial primary ribs complete ; between them numerous (twenty-
four to thirty-six) thinner secondary, and very numerous (more than one hundred) tertiary ribs.
Margin reflexed, like the curved brim of a hat.

Dimensions. — Shell 012 long,, 0-27 broad..

Habitat. — Central Pacific, Station 274, surface.

Subgenus 2. Litharachnoma, Haeckel.

Definition. — Apex with four cortinar pores (two anterior jugular' and two posterior
cardinal pores).

5. Litharachnium discoides, n. sp.

Shell flat, funnel-shaped, nearly discoidal, with concave outlines. Apex with four unequal
cortinar pores (two smaller jugular and two larger cardinal pores). Twelve strong primary or
perradial ribs alternating with twelve weaker secondary or interradial ribs ; between these there are
twenty-four shorter tertiary or adradial ribs, and in the outer flat, discoidal, half of the shell very
numerous peripheral radial ribs (more than two hundred to three hundred). Margin flat, discoidal.

Dimensions. — Shell about 0'2 long, 112 broad.

Habitat. — Equatorial Atlantic, Station 34*7, surface.

6. Litharachnium pilidium, n. sp.

Shell flat, hat-shaped, with S-shaped outlines, in the upper half convex, in the lower half
concave. Apex with four equal crossed cortinar pores. Thirty primary ribs of equal size; four of
them are the prolongations of the four cortinar beams, eight intercalate between these secondary,

REPORT ON THE RADIOLARIA. 1165

and the other eighteen tertiary. Between them very numerous peripheral beams. Margin broad
horizontal, reflexed like the brim of a " Bismarck " hat.

Dimensions. — Shell 0'17 long, 0'38 broad.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

•

Genus 515. Cladarachnium,1 Haeckel, 1881, Prodromus, p. 430.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) with flatly
conical, tent-shaped or nearly discoidal shell, and numerous branched radial beams.

The genus Cladarachnium differs from the preceding Litharachnium only in the
ramification of the radial beams, the distal' ends of which project over the margin of the
shell. Only one species of the genus has been observed.

1. Cladarachnium ramosum, n.. sp. (PI. 55, figs. 5, 6).

Shell flatly conical or tent-shaped, with nearly straight lateral outlines; apical part somewhat
higher. Apex with three cortinar pores, surrounded by a few girdles of larger pores. From these
there arise about twelve to fifteen strong radial beams at unequal' distances; these are somewhat
curved and irregularly branched. The network between them has irregular polygonal meshes and is
more delicate towards the periphery. Margin with twenty-four to thirty irregular indentations or
concave excisions, separated by the prominent distal ends of the branched ribs.

Dimensions. — Shell 0416 long, 0'4 broad.

Habitat. — Central Pacific, Station. 271, surface..

Genus 516. CyrfopHormis,2 n. gen.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) with ovate
or urceolate shell and numerous radial ribs in its wall. Mouth more or less con-
stricted, smooth, truncated. Apex without horn.

The genus Cyrtophormis, like the preceding genera, exhibits numerous prominent
radial or longitudinal ribs in the wall of the urceolate shell ; it differs from these in
the constricted and truncated mouth, with smooth margin of the peristome.

1. Cyrtophormis pila, n. sp. (PI. 52, fig. 1).

Shell balloon-shaped, subspherical, with twenty denticulate meridional ribs, alternating with
twenty longitudinal rows of circular pores, which are twice as broad as the bars. Peristome con-
stricted and then dilated, smooth, half as broad as the shell.

Dimensions. — Shell Oil long, 0'09 broad; mouth 0'06 broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

1 Cladarachnium = Spider-web with branched threads ;

2 Cyrtophormis = Fishing- basket ;

1166 THE VOYAGE OF H.M.S. CHALLENGER.

2. Cyrtophormis cerostatica, n. sp. (PI. 52, figs. 2, 3).

Shell balloon-shaped, subspherical, with twenty smooth meridional ribs, alternating with twenty
longitudinal rows of circular pores, of the same breadth as the bars. Peristome constricted, about
half as broad as the shell.

Dimensions. — Shell 009 long, 0'07 broad ; mouth 0'03 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Cyrtophormis spiralis, n. sp. (PI. 51, fig. 9).

Shell ovate, one and a half times as long as broad, with twenty spirally convoluted, elegantly
denticulated ribs, alternating with twenty spiral rows of small circular pores, of about the same
breadth as the bars. Peristome constricted, very small, only one-seventh as broad as the shell.

Dimensions. — Shell O'l long, 0-OY broad ; mouth 0"01 broad.

Habitat. — West Tropical Pacific, Station 225, depth 4475 fathoms.

1

4. Cyrtophormis tabulata (PI. 79, fig. 2).

Shell urceolate and tabulate, twice as long as broad, with twenty-five to thirty denticulated
longitudinal ribs, crossed by twenty to twenty-four transverse rings. Pores therefore regularly
disposed in longitudinal and transverse rows ; each pore circular, with a square frame. Peristome
constricted, scarcely half as broad as the shell.

Dimensions. — Shell O2 long, 01 broad ; mouth 0'04 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

Genus 517. Haliphormis,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin, p. 54 (sensu mutato).

Definition. — A rchiphormida (vel Monocyrticla multiradiata aperta) with
numerous radial ribs in the wall of the campanulate shell, prolonged into free terminal
feet. Apex with a horn.

The genus Halipliortnis (with an apical horn) and the following Archiphormis
(without a horn) comprise those Archiphormida in which the open mouth is more or less
constricted and surrounded by a coronet of radial feet, as terminal prolongations of the
radial ribs of its wall. The few forms, upon which Ehrenberg originally founded the
genus Haliphormis, are partly not recognisable, partly belong to other genera. We
therefore give here a new definition of the genus, as stated in my Prodromus, 1881,
p. 428.

1 Haliphormis= Sea-basket ; «A

REPORT ON THE RADIOLARIA. 1167

1. Haliphormis lagena, n. sp. (PI. 97, fig. 5)

Shell bottle-shaped, twice as long as broad, tapering towards both ends, with nine longitudinal
curved ribs. These are connected by irregular transverse beams, and the quadrangular meshes, so
produced, are filled up by irregular, delicate, arachnoidal framework. The constricted mouth is
half as broad as the middle part of the shell and surrounded by nine slender convergent feet,
the free distal ends of the ribs. The apex bears a small knob with an oblique horn, perhaps the
rudimentary cephalis of Sethamphora or Sethopyramis (?).

Dimensions. — Shell 0'6 to 07 long, 0'3 to 0'4 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

2. Haliphormis costata, n. sp.

Shell campanulate, somewhat longer than broad, with twelve prominent longitudinal ribs,
alternating with twelve rows of regular circular pores. Mouth constricted, half as broad as the
shell, with twelve long triangular feet, formed by the free distal ends of the ribs. Apical horn
short and stout, triangular pyramidal.

Dimensions. — Shell 012 long, 01 broad ; mouth 0/07 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 518. Archiphormis? Haeckel, 1881, Prodromus, p. 428.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) with
numerous radial ribs in the wall of the campanulate or urceolate shell, prolonged into
free terminal feet. Apex without horn.

The genus Archiphormis differs from the preceding Haliphormis, its probable
ancestral form, in the absence of the apical horn. The number of the longitudinal ribs,
which are prolonged into terminal feet, is from six to nine or twelve or even more.

1. Archiphormis cancellata, Haeckel.

(?) Halicalyptra cancellata, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 243.

Shell cup-shaped or campanulate, with six prominent ribs, prolonged into six terminal
triangular feet, one-third as long as the shell. Ribs connected by five or six transverse horizontal
rings ; meshes between them rounded squarish. (As Ehrenberg has given no figure of this species,
its identity with the Challenger specimen is doubtful.)

Dimensions. — Shell 0'08 long, O'OG broad ; mouth 0'04 broad.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

1 Archiphormis = Primordial-basket ; ei^

1168 THE VOYAGE OF H.M.S. CHALLENGER.

2. Archiphormis campanulata, n. sp.

Shell campanulate, with nine prominent denticulate ribs, prolonged into nine terminal feet,
which are broad, lamellar, truncate, nearly vertical, one-third as long as the shell. Pores between
the ribs circular, disposed in nine longitudinal and seven to eight transverse rows.

Dimensions. — Shell 0'09 long, Ol broad ; mouth 0'06 broad.

Habitat. — Central Pacific, Station 270, depth 2925 iathoms.

3. Archiphormis urceolata, n. sp. (PL 98, fig. 11).

Shell urceolate, with nine smooth prominent curved ribs, prolonged into nine triangular
convergent short feet, scarcely one-sixth as long as the shell. Pores between the ribs in nine
regular longitudinal rows, twice or three times as broad as long, quadrangular, eight to twelve
pores in each row. Mouth constricted, half as broad as the shell.

Dimensions. — Shell 0'13 long, Oil broad ; mouth 0'06 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 519. Halicalyptra,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.
d. Wiss. Berlin, p. 54 (sensu emendato).

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) without
radial ribs in the wall of the campanulate or ovate shell. Mouth with a coronet of
radial feet. Apex with a horn.

The genus Halicalyptra and the two following closely allied genera differ from the
preceding Archiphormida in the absence of radial ribs. The multiradiate structure is
indicated only by the terminal spines or feet, forming a coronet around the mouth.
These feet are either the free ends of reduced ribs, or new productions of the peristome.
Halicalyptra may be derived from Calpophcena and Petalospyris by loss of the basal
lattice-plate of the cephalis. But it is also possible that it has been derived from
Anthocyrtis by loss of the cephalis, and that its shell corresponds to the thorax of the
latter.

Subgenus 1. Acrocalpis, Haeckel, 1881, Prodromus, p. 427.

Definition. — Shell smooth, without spines or thorns (other than the feet and the
apical horn).

1 Halicalyptra = Sea-veil ; «AJ,

REPORT ON THE RADIOLARIA. 1169

1. Halicalyptra virginica, Ehrenberg.

Halicalyptra virginica, Ehrenberg, 1854, Mikrogeol., Taf. xviii. fig. 110.

Halicalyptra virginica, Haeckel, 1862, Monogr. d. Radiol., p. 289.

Haliomma virginicum, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 71.

Acrocalpis virginica, Haeckel, 1881, Prodromus, p. 427.

Shell smooth, campanulate, nearly hemispherical. Pores subregular circular, about as broad as
the bars. Horn conical, half as long as the shell. Peristome scarcely constricted, with six conical
divergent feet, as long as the horn.

Dimensions. — Shell diameter 0'04 to 0'05, length of the feet 0'02.

Habitat. — Fossil in tertiary rocks of Barbados and North America (Eichmond, Virginia).

2. Halicalyptra campanula, n. sp.

Podocyrtis spinosa, Bury, 1862, Polyeystins of Barbados, pi. xvii. fig. 3.

Shell smooth, campanulate. Pores irregular, roundish, about as broad as the bars. Horn large
conical, about as long as the shell. Peristome not constricted, with six large divergent feet, which
are as long as the shell, lamellar, with dentate edges.

Dimensions. — Shell diameter 0'07, length of the feet 0'07.

Habitat. — Fossil in Barbados.

3. Halicalyptra ampulla, n. sp.

Petalospyris foveolata, var., Bury, 1862, Polyeystins of Barbados, pi. ix. fig. 1.

Shell smooth, subspherical, inflate. Pores regular, circular, twice as broad as the bars. Horn
slender conical, about as long as the shell. Peristome constricted, with six divergent cylindrical,
irregularly curved feet, twice to three times as long as the shell.

Dimensions. — Shell diameter 012, feet 0'2 to 0'3 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; also fossil in Barbados.

4. Halicalyptra novena, n. sp.

Shell smooth, campanulate. Pores irregular, roundish. Horn slender conical, about as long as
the shell. Peristome slightly constricted, with nine slender divergent feet of the same length.
(Very similar to Petalospyris foveolata, Ehrenberg, but without internal columella and ring, with
perfectly simple shell-cavity and open mouth.)

Dimensions. — Shell 0'09 diameter, feet O'l long.

Habitat. — Fossil in Barbados.

5. Halicalyptra petalospyris, n. sp. (PI. 98, fig. 12).

Shell smooth, campanulate. Pores small, circular, irregularly scattered. Horn stout,
pyramidal, about as long as the shell. Peristome scarcely constricted, with fifteen to twenty broad

(ZOOL. CHALL. BXP. — PART XL. — 1886.) Rl 147

1170 THE VOYAGE OF H.M.S. CHALLENGER.

lamellar or lanceolate feet, which are twice to three times as long as the shell, parallel and vertical.
(Very similar to Petalospyris flabellum, &c., Ehrenberg, 1875, loc. cit., Taf. xxii. figs. 6-8, but without
any trace of sagittal ring or columella.)

Dimensions. — Shell 0'05 to 0'08 diameter, feet 0'15 to 0'25 long.

Habitat. — Central Pacific, Stations 266 to 268, depth 2*700 to 2900 fathoms.

Subgenus 2. Echinocalpis, Haeckel, 1881, Prodromus, p. 427.

Definition. — Shell spiny, covered with numerous spines or thorns (besides the
feet and the apical horn).

6. Halicalyptra spinosa, n. sp.

Shell spiny, ovate, inflate in the apical half. Pores irregular polygonal, four to eight times as
broad as the bars. Peristome constricted, half as broad as the shell, with nine slender divergent
feet, which like the apical horn are curved, twice to three times as long as the shell and five to ten
times as long as the numerous bristles of the surface.

Dimensions. — Shell 0'08 long, 0'06 broad ; feet 015 to 0'25 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

7. Halicalyptra castanella, n. sp.

Shell spiny, nearly spherical. Pores irregular roundish. Peristome constricted, scarcely one-
third as broad as the shell, with twelve to twenty slender, widely divergent feet, which like the
horn are irregularly curved, and longer than the shell. (Very similar to certain forms of the
Phaeodarium Castanella, PL 113, fig. 2.)

Dimensions. — Shell 013 diameter, feet 015 to 018 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 520. Carpocanistrum,1 n. gen.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) without
radial ribs in the wall of the campanulate or ovate shell. Mouth with a corona of
radial feet. Apex without horn.

The genus Carpocanistrum differs from the similar preceding Halicalyptra in the
loss of the apical horn. It is very nearly related to the Dicyrtid Carpocanium and
may be easily confounded with it. But in the latter the uppermost part of the shell-
cavity includes a rudimentary cephalis with a cortinar septum, whilst in Carpocanistrum

1 Carpocanistrum = Small fruit-basket ; x«jW;,

REPORT ON THE RADIOLARIA. 1171

the cephalis is entirely lost, and the inner cavity quite simple. The number of the
feet of the peristome is from nine to twenty, sometimes more. The mouth is
commonly more or less constricted.

1. Carpocanistrum novenum, n. sp.

Shell ovate, smooth, one and a third times as long as broad. Pores regular circular, hexagon-
ally framed, three times as broad as the bars, eight to ten on the greatest breadth of the shell.
Peristome strongly constricted, one-third as broad as the shell, with nine large ovate lamellar,
slightly convergent feet.

Dimensions. — Shell O08 long, 0'06 broad ; mouth 0'02 broad.

Habitat. — South Atlantic, Station 325, surface.

2. Carpocanistrum flosculum>, n. sp. (PI. 52, fig. 9).

Shell campanulate, rough, thick-walled, of equal breadth and length. Pores regular circular, of
the same breadth as the bars, twelve to fifteen on the greatest breadth of the shell. Peristome
slightly constricted, with twelve elegant lanceolate, nearly vertical, a little convergent feet.

Dimensions. — Shell 0'07 long, 0'07 broad ; mouth 0'05 broad.

Habitat. — Equatorial Atlantic, Station 347, surface.

3. Carpocanistrum giganteum, n. sp.

Shell ovate, smooth, very thick-walled, one and a third times as long as broad. Pores very
numerous and small, subregular circular, forty to fifty on the greatest breadth of the shell, of about
the same breadth as the bars. Peristome small, constricted, scarcely one-fourth as broad as the
shell, with twelve to fifteen short triangular vertical feet.

Dimensions. — Shell 0428 to 0'31 long, 0'21 to 0'23 broad ; mouth 0'06 to 0'07 broad.

Habitat. — Fossil in Barbados.

4. Carpocanistrum acephalum, n. sp. (PI. 52, fig. 10).

Shell ovate, smooth, thin -walled, one and a fifth times as long as broad. Pores subregular
circular, twice as broad as the bars, sixteen to twenty on the greatest breadth of the shell. Peri-
stome slightly constricted, with fifteen to eighteen slender, slightly bent, nearly vertical, and parallel
feet, which are half as long as the shell.

Dimensions. — Shell 012 long, O'l broad ; mouth 0~07 broad.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

1172 THE VOYAGE OF H.M.S. CHALLENGER.

5. Carpocanistrum evacuatum, n. sp. (PL 52, fig. 11).

Shell urceolate, smooth, thin-walled, one and a half times as long as broad. Pores regular
circular, sixteen to twenty on the greatest breadth of the shell. Peristome slightly constricted,
with twenty to twenty-five small triangular vertical feet.

Dimensions. — Shell 01 long, 0'07 broad ; mouth 0'05 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Carpocanistrum pyriforme, Haeckel.

Lithocarpium pyriforme, Stohr, 1880, Palseontogr., vol. xxvi. p. 97, Taf. iii. fig. 10.

Shell pear-shaped or subspherical, one and a fourth times as long as broad. Pores roundish,
polygonally framed (or with square meshes ?). Peristome strongly constricted, one-fourth as broad as
the shell, somewhat tubular, with twelve to twenty short vertical and parallel feet. The position
of this species is doubtful ; perhaps it represents a peculiar genus.

Dimensions. — Shell 017 long, 014 broad ; mouth 0'035 broad.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte) Stohr.

Genus 521. Arachnocalpis,1 Haeckel, 1881, Prodromus, p. 427.

Definition. — A rchiphormida (vel Monocyrtida multiradiata aperta) with an
ellipsoidal or nearly spherical double shell; outer shell arachnoidal or spongy. Peristome
small, constricted, with a corona of numerous radial feet. No apical horn.

The genus Arachnocalpis differs from the other Archiphormida by possessing a
double shell (like Peripyramis). The large shell, reaching nearly half a millimeter
in length, is either ellipsoidal or nearly spherical, and composed of an inner primary
and an outer secondary shell. Its network is very delicate, in the outer envelope
either spongy or arachnoidal. This very remarkable genus has probably no true
relation to the other Archiphormida, but has been derived from true Calpoidea
(Mitrocalpis) by development of a corona around the mouth.

1. Arachnocalpis ellipsoides, n. sp. (PL 98, fig. 13).

Shell ellipsoidal, one and a half times as long as broad, on the apical pole hemispherical, on

the basal pole coronate, with an elegant prominent funnel-shaped peristome, which is one-eighth as

broad as the shell, fenestrated by very fine pores, and bears fifteen to twenty short conical divergent

teeth. Inner shell with irregular polygonal meshes of very different size, separated by thin, finely-

1 Arachnocalpis = Urn enveloped by spider's web;

REPORT ON THE RADIOLARIA. 1173

denticulate bars. Outer spongy shell very delicate, arachnoidal, with numerous prominent conical
spongy papillae. Central capsule ellipsoidal, half as long and broad as the shell.

Dimensions. — Shell 0'46 long, O32 broad ; mouth 0'045 broad.

Habitat. — Central Pacific, Stations 271 to 274, surface.

2. Arachnocalpis sphceroides, n. sp.

Shell spheroidal, of the same structure as the preceding ellipsoidal species, with the same form of
the spongy envelope ; differing from it in the globose form and the shorter peristome, bearing only
nine or ten small conical divergent teeth. Central capsule spherical.

Dimensions. — Shell 0'3 diameter, mouth 0'04 broad.

Habitat. — Central Pacific, Stations 265 to 270, surface.

Subfamily 2. ARCHIPH^NIDA, Haeckel, 1881, Prodromus, p. 429.

Definition. — P hsenocalpida with the basal mouth of the shell fenestrated
(vel Monocyrtida multiradiata clausa).

Genus 522. Phcenocalpis,1 n. gen.

Definition. — A rchiperida (vel Monocyrtida multiradiata clausa) with an
internal axial simple columella, prolonged outside into an apical horn.

The genus Phcenocalpis and the following Phcenoscenium comprise those Archi-
phsenida in which the vertical axis of the shell -cavity is occupied by a simple or
branched columella, arising from the centre of the base and prolonged into an apical
horn. This columella may be either the vertical rod of a Plectaniscus or the remnant
of an original ring of Petalospyris. The latter genus differs by its sagittal constriction.

1. Phcenocalpis petalospyris, n. sp. (PL 97, fig. 4).

Shell subspherical, rough, with irregular, roundish pores, larger than the bars. Columella
straight, central, thin, prolonged into a large apical horn with three dentate edges. Six basal feet
curved, divergent, lamellar, with a middle rib and dentate edges.

Dimensions. — Shell 0'07 long, 0'05 broad ; horn and feet 0'06 long.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

1 Ph&nocalpis = Urceolate shell ; <p*i>a, xaXx/f.

1174 THE VOYAGE OF H.M.S. CHALLENGER.

2. Phcenocal$>is ocellata, Haeckel.

Petalospyris ocellata, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii.
fig. 9.

Shell subspherical, smooth, with irregular roundish pores, about as broad as the bars.
Columella slightly curved and excentric, prolonged into a slender conical horn of the same length.
Six basal feet similar to the horn, slightly divergent.

Dimensions. — Shell 0'06 long, 0'07 broad ; horn and feet 0'05 long.

Habitat. — Fossil in Barbados.

3. Phcenocalpis carinata, Haeckel.

Petalospyris carinata, Ehrenberg, 1875, Abhancll. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xxii.
fig. 6.

Shell campanulate, rough, with irregular roundish pores, smaller than the bars. Columella
straight, central, prolonged into a stout conical horn of the same length. Nine basal feet slender,
triangular, longer than the shell, nearly vertical, with a middle rib in the basal half.

Dimensions. — Shell O05 long, 0'06 broad ; horn 0'04 long, feet 0'08 long.

Habitat. — Fossil in Barbados.

4. Phcenocalpis flabellum, Haeckel.

Petalospyris flabdlum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, Taf. xxii. fig. 7.

Shell campanulate smooth, with very small circular pores, half as broad as the bars. Columella
straight, central, prolonged into a pyramidal horn of half the length. Twelve to fifteen basal feet
lamellar, linear, twice to three times as long as the shell, parallel and vertical, pointed at the distal
end.

Dimensions. — Shell 0'04 long, 0'05 broad ; horn 0'02 long, feet 01 to 012 long.

Habitat. — Fossil in Barbados.

Genus 523. Phcenoscenium,1 n. gen.

Definition. — A rchiphsenida (vel Monocyrtida multiradiata clausa) with an
internal axial branched columella, prolonged outside into an apical horn.

The genus Phcenoscenium differs from the preceding Phosnocalpis in the branched
columella, which is connected by three or six ascending branches with the inner wall of
the shell. It bears therefore to the latter the same relation that Cladoscenium exhibits
to Euscenium. The former genera may have been derived from the latter by inter-
polation of new interradial feet between the three primary perradial feet.

1 Phanoscenium = Tent-shaped shell ; Qulmc, ex-wtou.

EEPOKT ON THE EADIOLARIA. 1175

1. Phcenoscenium hexapodium, n. sp. (PL 98, fig. 9).

Shell campanulate, smooth, about as long as broad. Network delicate, with irregular polygonal
pores and thin bars. Columella with four to six ascending three-branched verticils, prolonged
into the conical hollow apical horn (with six to eight smaller verticils) which is about as long
as the shell. Six basal feet curved, divergent, of the same length, with pinnate middle rod.

Dimensions. — Shell O'l long, O'll broad ; horn and feet 0'08 to 0'09 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Phcenoscenium cladopodium, n. sp.

Shell campanulate, conical, smooth, somewhat broader than long. Network with irregular
roundish pores, about as broad as the bars. Columella with a single verticil of three ascending
branches. Horn pyramidal, stout, as long as the shell, with three dentate edges. Six feet
divergent, slightly curved, very unequal ; three primary (or perradial) very large, longer than the
shell, three-sided pyramidal, with three dentate edges ; three secondary (or interradial) much
smaller, simple, shorter than the shell.

Dimensions. — Shell 0'05 long, 0'06 broad; horn and feet 0'04 to 0'07 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Phcenoscenium polypodium, n. sp.

Shell subspherical, about as long as broad, smooth. Network with regular circular pores, twice
as broad as the bars. Columella with two verticils of three ascending branches, prolonged into a
stout conical horn of twice the length. Twelve to fifteen conical curved divergent feet, about as
long as the shell. The three primary feet are directly connected with the base of the columella.

Dimensions. — Shell 0'08 diameter, horn 015 long, feet 0'07 to 0'09 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 524. Calpophcena,1 Haeckel, 1881, Prodromus, p. 429.

Definition. — A rchiphsenida (vel Monocyrtida multiradiata clausa) with an
apical horn and simple internal cavity of the shell, without axial columella.

The genus Calpophcena and the following closely allied Archiphcena differ from
the two preceding genera of Archiphsenida in the simple shell cavity, which encloses no
columella. They may be derived either from the preceding Phoenocalpis by loss of the
columella, or directly from the Zygospyrida by reduction of the sagittal constriction and
loss of the primary ring. Different subgenera may be distinguished in Calpophcena
according either to the number of the feet or to their shape (being simple or branched).

1 Calpophrena=\Jiceo]a.te shell;

1176 THE VOYAGE OF H.M.S. CHALLENGER.

•

Subgenus 1. Acrocorona, Haeckel, 1881, Prodromus, p. 430.

Definition. — Feet simple, not branched nor forked.

1. Calpophcena tetrarrhabda, n. sp.

Shell subspherical, tuberculate, with subregular circular pores. Apical horn conical, about as
long as the shell. Basal plate with a regular cross of four equal cortinar pores, separated by four
bars ; these are crossed in the sagittal and frontal diameter, and prolonged into four equal conical
divergent feet, about as long as the shell.

Dimensions. — Shell 01 diameter, horn and feet 01 to 012 long.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

2. Calpophcena hexarrhabda, n. sp. (PL 53, figs. 17, 18).

Shell subspherical, rough, with irregular roundish pores. Apical horn conical, shorter than the
shell. Basal plate (fig. 18) with three pairs of triangular pores, two larger (cardinal) pores in the
middle, two smaller (cervical) at the dorsal, and two intermediate (jugular) at the ventral side.
The bars between them are prolonged into six equal cylindrical divergent feet, nearly as long as the
shell, provided with a spiny knob at the end.

Dimensions. — Shell 0'09 long, 0'08 broad ; horn and feet 0'06 to 0'08 long.

Habitat. — Tropical Pacific, Station 224, depth 1850 fathoms.

3. Calpophcena ennearrhabda, n. sp.

Shell subspherical, spiny, with irregular, roundish pores. Apical horn cylindrical, longer than
the shell. Basal plate with nine collar pores, three larger central alternating with three pairs of
smaller peripheral (like PI. 87, fig. 2). Corona with nine slender cylindrical, slightly curved,
divergent feet, somewhat longer than the shell.

Dimensions. — Shell Oil long, 01 broad ; horn and feet 012 to 015 long.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

4. Calpophcena enneaphylla, n. sp.

Shell ovate, smooth, with regular circular pores. Apical horn pyramidal, half as long as the
shell. (Basal plate with four cortinar pores?) Corona with nine broad, lamellar, truncate,
vertical feet, about as long as the horn.

Dimensions. — Shell 012 long, 0'09 broad ; horn and feet 0'06 long.

Habitat. — Central Pacific, Station 271, surface.

REPORT ON THE RADIOLARIA. 1177

5. Calpophcena petalospyris, n. sp.

Shell campanulate, tuberculate, with irregular, roundish pores. Apical horn conical, shorter
than the shell. (Basal plate with nine pores ?) Corona with twelve to twenty broad, lamellar,
truncate, vertical feet, of different sizes, somewhat irregular.

Dimensions. — Shell O08 long, 0'09 broad ; horn and feet 0'07 to 012 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Subgenus 2. Cladocorona, Haeckel, 1881, Prodromus, p. 430.
Definition. — Feet branched or forked.

6. Calpophcena tetracorethra, n. sp.

Shell subspherical, smooth, with irregular, roundish pores. Basal plate with four larger pores.
Apical horn and the four divergent basal feet of equal size and similar form, three to four times as
long as the shell, slender, bristle-shaped, curved, in the distal half irregularly branched. (Very
similar to the remarkable Tctraspyris tetracorethra, PL 53, figs. 19, 20, but with shorter appendages
and with simple spherical shell, which exhibits no trace of sagittal ring and constriction.)

Dimensions. — Shell 012 diameter, horn and feet 0'3 to 0'5 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

7. Calpophcena hexacorethra, n. sp.

Shell subspherical, smooth, similar to the preceding species. Basal plate with six pores.
Apical horn and the six divergent feet twice to three times as long as the shell, bristle-shaped,
irregularly curved and branched. (Similar to Hexaspyris hexacorethra, PI. 95, fig. 8, but without
sagittal ring and constriction.)

Dimensions. — Shell Oil long, 013 broad; horn and feet 0'2 to 0'3 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 525. Archiphcena,1 Haeckel, 1881, Prodromus, p. 429.

Definition. — A rchipheenida (vel Monocyrtida multiradiata clausa), with simple
internal cavity of the shell, without apical horn and axial columella.

The genus Archiphcena has the same simple cavity of the shell as the preceding
Calpophcena, but differs from it in the loss of the apical horn. It bears therefore
to the latter the same relation that Gorgospyris does to Petalospyris. The two
former genera may be derived from the two latter by loss of the sagittal ring and
constriction.

1 Archiphcena = Primordial shell ; b^w, Qatva.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 148

1178 THE VOYAGE OF H.M.S. CHALLENGER,

Subgenus I. Coronopltcena, Haeckel, 1881, Prodromus, p. 429.
Definition. — Feet simple, not branched nor forked.

1. Archiphcena gorgospyris, n. sp. (PI. 98, figs. 10, 10a).

Shell hemispherical, smooth, with small subregular, circular pores. Collar septum with four
large pores (fig. 10a). Twelve to fifteen feet, divergent, lamellar, truncate, about as long as the shell.
(Similar to certain forms of Gorgospyris, PI. 87, figs. 1 to 3, but with simple shell cavity, without
sagittal ring and constriction, and without a columella.)

Dimensions. — Shell 0'08 long, 0'04 broad; feet 0'03 to 0'04 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

2. Archiphoena corona, n. sp.

Shell crown-shaped, somewhat broader than long, at the base flattened, papillate, with irregular
roundish pores. Twenty to twenty-five feet, broad, lamellar, truncate, nearly vertical, about twice as
long as the shell.

Dimensions. — Shell 01 long, 012 broad; feet 0'2 to 0'22 long.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Subgenus 2. Stephanophcena, Haeckel, 1881, Prodromus, p. 429.
Definition. — Feet branched or forked.

3. Archiphcena stephanoma, n. sp.

Shell campanulate, somewhat longer than broad, with subregular, circular pores. Margin of the
flattened base with a corona of about twenty unequal feet, which are partly simple, partly irregularly
branched, and about as long as the shell.

Dimensions. — Shell Oil long, 0'03 broad ; feet 0'08 to 012 long.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Family LXI. CYB.TOCALPIDA, n. fam.

Archicorida et Arehicapsida, Haeckel, 1881, Prodromus, pp. 427, 428.

Definition. — M onocyrtida eradiata. (Cyrtoidea with a simple, not jointed
shell, representing a simple cephalis without radial apophyses.)

The family Cyrtocalpida, composed of the Archicorida and Arehicapsida of my

REPORT ON THE RADIOLARIA.

1179

Prodromus, comprises those Cyrtoidea in which the lattice-shell is quite simple, with-
out transverse constriction, and without radial apophyses. The two subfamilies differ in
the shape of the basal mouth, which in the Archicorida is a simple wide opening, but in
the Archicapsida is closed by a lattice-plate.

Only a few species of this family were formerly known. Ehrenberg, in 1838, founded
upon these the genus Cornutella, one of the three oldest genera of Polycystina
(Cornutella, Lithocampe, Haliomma). In 1862 I described some living forms, with
a central capsule, as Cyrtocalpis. The Challenger collection contains a large number of
new genera and species.

Probably the family Cyrtocalpida is an artificial group, comprising two or more
different subfamilies of very different origin. The Cornutellida (Cornutella, Cornu-
tanna) have probably been derived from the Sethocorida by loss of the cephalis, so that
their conical shell represents a thorax alone. The Mitrocalpida on the other hand
(genera 528—531) may be originally simple ovate shells (like Gromia and • Lecythium),
arising independently from the Nassellida. The Archicapsida (Halicapsa, Archicapsa)
are probably derived from the Zygospyrida (Dictyospyris, Circospyris) by loss of the
sagittal ring and constriction. This is nearly certain, when the three or four typical
cortinar pores appear in their basal plate. Some forms of Halicapsa, may be easily
confounded with some forms of Prunoidea (Lithapium).

Those Cyrtocalpida, which possess a central capsule with three or four lobes, are
probably derived from Tripocyrticla by loss of the three feet, or from Sethocyrtida by
loss of the cephalis, since the lobes indicate the original presence of cortinar pores and
of a cephalis. Those Cyrtocalpida, however, in which a simple ovate shell encloses a
simple central capsule without lobes, may be original " Monocyrtida eradiata," without
relation to any radial ancestral forms.

I. Subfamily

Archicorida.
Basal mouth of the J
shell a simple wide
opening.

Synopsis of the Genera of Cyrtocalpida.

Shell conical, gradu- ( With horn,

ally dilated to <

Shell with simple wards the mouth. ( No horn,
lattice-work (not •{
double or spongy). I Shell ovate or urceo- ( With horn,

late, with con- -j
[ stricted mouth. ( No horn,

f Shell ovate, double, with an external

, mantle, ....

Shell not simply J

Shell ovate, with spongy irregular lattice-
work, ....

latticed.

[

Shell with an apical horn,

II. Subfamily

Archicapsida.
Mouth closed by a tot- 1 gl n without hom Qn the
tice plate.

526. Cornutella.

527. Cornutanna.

528. Arehicorys.

529. Cyrtocalpis.

530. Mitrocalpis.

531. Spongocyrlix.

532. Halicapfa.

533. Archicapsa.

1180 THE VOYAGE OF H.M.S. CHALLENGER.

Subfamily 1. ARCHICORIDA, Haeckel, 1881, Prodromus, p. 427.

Definition. — C yrtocalpida, with the basal mouth of the shell open (vel Mono-
cyrtida eradiata aperta).

Genus 526. Cornutella,1 Ehrenberg, 1838, Abhandl. d. k. Akad.
d. Wiss. Berlin, p. 128.

Definition. — A rchicorida with conical shell, gradually dilated towards the wide
open mouth. Apex armed with a horn.

The genus Cornutella is one of the three oldest genera of Polycystina, described
by Ehrenberg, in 1838 (Cornutella, Lithocampe, and Haliomma). He afterwards
enumerated, in 1872 and 1875, a large number of fossil and living species, the majority
of which, however, belong to other genera of Monocyrtida and Dicyrtida (at least six
or seven different genera). We retain here as the true type of the genus the oldest
known species: — Cornutella clathrata, and the nearly allied forms Cornutella stylo-
phcena, Cornutella mitra, Cornutella circularis, &c. The simple conical shell exhibits
no distinct trace of an original cephalis, excepting the apical horn; it may have origin-
ated either independently, or been derived from Sethoconus, by loss of the cephalis.

Subgenus 1. Cornutellium, Haeckel.

Definition. — Axis of the conical shell straight. Pores polygonal, or roundish with
polygonal frames.

1. Cornutella hexagona, n. sp. (PL 54, fig. 9).

Shell slender, conical, with straight outlines. Pores subregular, hexagonal, gradually increasing
in size towards the mouth ; in about ten to twelve longitudinal series, in the upper part very small.
Horn slenderly conical, nearly bristle-shaped, long.

Dimensions.— Shell 01 to 015 long, 0'04 to 0'06 broad.

Habitat. — Central Pacific, Stations 265 to 274, surface, and at different depths.

2. Cornutella sethoconus, n. sp. (PI. 54, fig. 10).

Shell slender, conical, with undulate outlines. Pores subregular, hexagonal, gradually increasing
in size towards the mouth, in about fifteen to eighteen longitudinal series, in the upper part circular.
Horn small, conical, short. The network is not so delicate as in the preceding similar species.

Dimensions. — Shell 012 to 016 long, 0'06 to 0'08 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

1 Cornutella = Small horn ; diminutive of cornu.

REPORT ON THE RADIOLARIA. 1181

3. Cornutella distenta, Ehrenberg.

Cornutella distenta, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wise. Berlin, p. 287, Taf. vi. III.

fig. 3.

Shell slender, conical, with straight outlines. Pores small, circular, regularly disposed in six to
eight alternating longitudinal rows, each pore surrounded by a large rhombic frame. The connected
frames form together a regular rhombic framework with obliquely crossed crests. Horn conical,
stout, large.

Dimensions. — Shell 01 to 015 long, 0'04 to 0'06 broad.

Habitat. — North Pacific, Californian Sea, depth 2600 fathoms, Ehrenberg.

4. Cornutella stiligera, Ehrenberg.

Cornutella stUigera, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 1; Abhandl. d. k. Akad. d.
Wiss. Berlin, 1875, p. 68, Taf. ii. fig. 3.

Shell slender, conical, with straight outlines. Pores subregular, rhombic or nearly square, dis-
posed in oblique series, separated by parallel obliquely ascending rings, which are crossed by
interrupted parallel bars. Horn slenderly conical or bristle-shaped, thin and long.

Dimensions. — Shell 0'08 to 012 long, 0'03 to 0'04 long.

Habitat. — Fossil in Barbados.

Subgenus 2. Cornutissa, Haeckel, 1881, Prodromus, p. 427.

Definition. — Axis of the conical shell straight. Pores circular or roundish, without
polygonal frames.

5. Cornutella circularis, Ehrenberg.

Cornutella circularity, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii. fig. 4.

Shell wide, conical or funnel-shaped, with straight outlines. Pores very large, circular, ten
to twenty times as broad as the bars, in about nine to twelve longitudinal alternating rows, increasing
gradually towards the mouth. Horn very large, cylindrical.

Dimensions. — Shell 01 to 015 long, 0'08 to 012 broad.

Habitat. — Fossil in Barbados.

6. Cornutella mitra, Ehrenberg.

Cornutella mitra, Ehreuberg,ll875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii. fig. 8.

Shell wide, conical, campanulate, with convex outlines. -Pores subregular, circular, nearly
equal in size, not regularly disposed in rows. Horn conical, stout.
Dimensions. — Shell 012 to 016 long, 0'08 to 012 broad.
Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

1182 THE VOYAGE OF H.M.S. CHALLENGER.

7. Cornutella clathrata, Ehrenberg.

Cornutella clathrata, Ehrenberg, 1838, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 129;

Mikrogeol., Taf. xxii. fig. 39.
Cornutella clathrata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, Taf. ii. fig. 9.

Shell wide, conical, with slightly convex outlines. Pores regular, circular, gradually increasing
in size towards the mouth, disposed in twelve to fifteen longitudinal alternating rows. Horn short
and stout, conical. (Compare Cornutella curvata.)

Dimensions. — Shell 015 to 0'2 long, 0'06 to O09 broad.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific ; also fossil in tertiary rocks of Barbados,
Nikobar and Sicily.

8. Cornutella stylophcena, Ehrenberg.

Cornutella stylophama, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287,

Taf. vi. III. fig. 1.

1 Cornutella tumens, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. vi. III.
%. 4.

Shell slender, conical, with undulate outlines. Pores subregular, circular, gradually increasing
in size, disposed in six to nine quincuncial alternating longitudinal rows. Horn very long, cylindro-
conical, sometimes about as long as the shell.

Dimensions. — Shell 01 to 013 long, 0'04 to 0'06 broad.

Habitat. — North Pacific, Californian Sea, depth 2600 fathoms.

9. Cornutella granulata, Ehrenberg.

Cornutella granulata, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. vi.
III. fig. 5.

Shell slender, conical, nearly cylindrical, with straight outlines, rounded at the apex. Pores
very small and numerous, punctiform, disposed into very numerous parallel transverse rows.
Horn small, conical (may be perhaps the shell of a Tintinnoid Infusorium ?).

Dimensions. — Shell 0'08 long, 0'02 broad.

Habitat. — North Pacific, Californian Sea, depth 2600 fathoms.

10. Cornutella annulata, Ehrenberg.

Cornutella annulata, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. ii.
fig. 16.

Shell slender, conical, nearly cylindrical, with straight outlines, rounded at the apex. Pores small
and numerous, regular circular, of equal size, regularly disposed in ten to fifteen parallel trans-
verse series. Horn bristle-shaped. (Compare Artostrobus annulatus, Cornutella annulata, Bailey.)

Dimensions. — SheU 01 to 013 long, 0'03 to 0'04 broad.

Habitat. — Cosmopolitan, Atlantic, Pacific, surface.

REPORT ON THE RADIOLARIA. 1183

Subgenus 3. Cornutosa, Haeckel, 1881, Prodromus, p. 427.
Definition. — Axis of the conical shell curved. Pores circular or roundish.

11. Cornutella curvata, Haeckel.

Cornutella dathrata, var., Ehrenberg, 1854, Mikrogeol., Taf. xxii. figs. 39a, b, c.
Cornutosa dathrata, Haeckel, 1881, Prodromus, p. 427.

Shell slender, conical, with curved axis ; the curve lies in one plane and is not spirally
convoluted. Pores subregular, circular, of nearly equal size, quincuncially disposed. Horn short,
conical.

Dimensions. — Shell 01 to 015 long, 0'04 to 0'06 broad.

Habitat. — Fossil in tertiary rocks of Sicily (Caltanisetta).

12. Cornutella spiralis, n. sp.

Cornutura qriralis, Haeckel, 1881, Prodromus, p. 427.

Shell slender, conical, nearly cylindrical, very long, spirally contorted ; its axis is an ascending
spiral line with two or three windings, widely distant. Pores irregular, square, small and numerous.
Dimensio'ns. — Shell 0'2 to 0'25 long, 0'05 to 0'08 broad.
Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 527. Cornutanna,1 Haeckel, 1881, Prodromus, p. 427.

Definition. — A rchicorida with conical shell, gradually dilated towards the wide
open mouth. Apex without horn.

The genus Cornutanna has the same simple conical shell as the preceding
Cornutella, but differs from it in the total absence of an apical horn. It bears there-
fore to the latter the same relation that Cyrtocalpis does to Archicorys. It may be
derived from Sethoconus by complete reduction of the cephalis and its horn.

1. Cornutanna orthoconus, n. sp.

Shell slender, conical,* with straight axis and straight outlines. Pores subregular, circular,
quincuncially disposed in nine to twelve alternating longitudinal series, gradually increasing in size
towards the mouth.

Dimensions. — Shell 01 to 012 long. 0*03 to 0'04 broad.

Habitat. — Central Pacific, Stations 270 to 274, surface.

1 Cornutanna = Horn-shaped ; Camilla.

1184 THE VOYAGE OF H.M.S. CHALLENGER.

2. Cornutanna cyrtoconus, n. sp.

Shell slender, conical, with curved axis ; the curve lies in one plane as in the similar
Cornutella curvata; the pores are smaller and more numerous than in this latter species, and the
rounded apex bears no horn.

Dimensions. — Shell 012 to 016 long, 0'05 to 0-07 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

3. Cornutanna loxoconus, n. sp.

Shell wide, conical, with irregularly curved axis ; the parts of the curve do not lie in one plane.
Pores very small and numerous, of nearly equal size.
Dimeiisions. — Shell 0'2 long, 012 broad.
Habitat. — Tropical Pacific, Station 225, depth 4475 fathoms.

Genus 528. Archicorys,1 Haeckel, 1881, Prodronms, p. 427.

Definition. — A rchicorida with simple urceolate or ovate shell, constricted
towards the mouth. Apex armed with a horn.

The genus Archicorys and the following closely allied Cyrtocalpis differ from the
two preceding genera in the ovate or urceolate form of the shell, which is more or less
constricted towards the terminal mouth. The upper pole in Archicorys bears an apical
horn, which is absent in Cyrtocalpis. The origin of these two genera may be the same,
probably arising directly fromNassellida, and independently of the triradiate Cyrtoidea
or bilocular Spyroidea. (Compare p. 1179.)

1. Archicorys galea, n. sp.

Shell smooth urceolate. Pores large, in the middle part hexagonal, towards both ends smaller
and polygonal. Apical horn stout, three-sided pyramidal, half as long as the shell. Mouth with a
short tubular peristome, about one-third as broad as the shell.

Z>m«7i»um&-r-Shell (without horn) 015 long, 012 broad ; horn 0'07 long, mouth 0-05 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

*

2. Archicorys ampulla, n. sp.

Shell smooth, thin-walled, bottle-shaped, in the upper half conical, in the lower half inflate,
subspherical. Pores subregular, circular, of the same breadth as the bars. Horn conical, stout,

1 A rchicaryt = Principal helm ;

REPORT ON THE RADIOLARIA. 1185

about one-third as long as the shell. Mouth truncate, without peristome, about half as broad as
the shell.

Dimensions. — Shell 015 long, 01 broad ; horn 0'05, mouth 0'05.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Archicorys microstoma, n. sp. (PL 51, fig. 12).

Shell rough, thick-walled, ovate. Pores large, subregular, circular, twice to four times as broad
as the bars. Horn small, conical, not larger than one pore. Mouth very small, truncate, scarcely
larger than one pore.

Dimensions. — Shell 01 long, 0'07 broad; horn 0'012, mouth 0'015.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

4. Archicorys globosa, n. sp.

Shell nearly spherical, thorny, thick-walled. Pores very large, circular, separated by spinulate
frames, smaller towards each pole. Horn conical, large, nearly as long as the radius of the shell ;
mouth truncate, simple, about one-third as broad as the shell.

Dimensions. — Shell diameter 013, horn 0'06, mouth 0-04.

Habitat. — Fossil in Barbados.

5. Archicorys ovata, n. sp. (PI. 51, fig. 10).

Shell ovate, rough, thick-walled. Pores regular, circular, of equal size, very small and numerous,
(juincuncially disposed. Horn small, conical, sometimes (as in the figured specimen) rudimentary.
When it becomes lost, the species may be called Cyrtocalpis ovata. Mouth truncate, small, simple,
one-sixth as broad as the shell.

Dimensions. — Shell 0'2 long, 015 broad ; horn O'Ol -to 0'03 long, mouth 0'03 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 529. Cyrtocalpis,1 Haeckel, 1860, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 835.

Definition. — Archicorida with simple urceolate or ovate shell, constricted
towards the mouth. Apex without horn.

The genus Cyrtocalpis comprises a large number of common, very primitive Monocyr-
tida, which in the simple ovate or urceolate form of the shell resemble the well known
Gromia among the Thalamophora. Its basal mouth is more or less constricted, as in

1 Cyrtocalpis= Basket-urn or wicker-pitcher ; xiifroj, X*XT/(.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 149

1186 THE VOYAGE OF H.M.S. CHALLENGER.

the preceding genus Archicorys, from which it differs in the total absence of an apical
horn. There is no trace of any triradial structure, excepting in some smaller species, in
which the basal part of the central capsule is trilobate ; these may be derived from the
Dicyrtides Sethocorys or Dictyocephalus, by loss of the cephalis and the cortinar
septum. But the larger species, which have a quite simple, ovate, central capsule
(PI. 51, fig. 13), have probably an independent origin, from Cystidium.

1. Cyrtocalpis urceolus, n. sp. (PI. 51, fig. 13).

Shell smooth, urceolate, with very delicate and elegant network. Pores in the middle part
large, regular, hexagonal, towards each pole smaller, irregular, roundish or polygonal. Mouth with
broad, hyaline, annular peristome, about one-third as broad as the shell.

Dimensions. — Shell 016 long, 012 broad ; mouth 0'05 broad.

Habitat. — Mediterranean (Portofino near Genoa), surface.

2. Cyrtocalpis reticulum, n. sp.

Shell smooth, urceolate, very similar to the preceding species, but differing from it in the
densely reticulated framework of the shell, which is composed of very numerous and small, irregular,
polygonal meshes of nearly equal size. Mouth without peristome, half as broad as the shell.

Dimensions. — Shell 018 long, 015 broad ; mouth 0'07 broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

3. Cyrtocalpis amphora, Haeckel.

Cyrtocalpis amphora, Haeckel, 1862, Monogr. d. Radio!., p. 286, Taf. v. iig. 2.

Shell smooth, urceolate, with regular, circular pores of equal size, of about the same breadth a.s
the bars. Mouth with smooth peristome, about half as broad as the shell.
Dimensions. — Shell 012 long, 0'08 broad ; mouth 0'04 broad.
Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific ; surface, and at various depths.

4. Cyrtocalpis urna, Stohr.

Cyrtocalpis urna, Stohr, 1880, Palseontogr., vol. xxvi. p. 96, Taf. iii. fig. 7.

Shell smooth, urceolate, with subregular, circular pores of different sizes, gradually increasing
towards the mouth, of about the same breadth as the bars. Mouth without peristome (?), about
half as broad as the shell.

Dimensions. — Shell 0'09 long, 0'06 broad ; mouth 0'035 broad.

Habitat. — Fossil in tertiary rocks of Sicily (Grotte).

REPORT ON THE RADIOLARIA. 1187

5. Cyrtocalpis sethopora, n. sp. (PL 52, fig. 4).

Shell smooth, urceolate, very thin-walled, with large irregular roundish meshes, each of which
is closed by a thin porous sieve-plate. Mouth two-thirds as broad as the shell, with a broad,
cmarginate, longitudinally striped peristome. (Perhaps the shell of a Tintinnoid Infusorium ?)

Dimensions. — Shell 0'08 long, O'Oo broad ; mouth 0'03 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Cyrtocalpis compacta, n. sp. (PL 52, figs. 7, 8).

Shell smooth, ovate, very thick-walled, with small, subregular, circular pores of equal size,
perpendicularly perforating the wall, about half as broad as the bars. Mouth small, only one-third
as broad as the compact shell. (Perhaps a reduced Lithocampe or Lithomitra ?)

Dimensions. — Shell 0'08 long, 0'04 broad ; mouth O'Olo broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

7. Cyrtocalpis lithomitra, n. sp. (PL 52, figs. 5, 6).

Shell smooth, slender, ovate, nearly cylindrical, with small subregular, circular pores, which are
disposed in nine to twelve transverse rows, and obliquely ascending perforate the wall. Mouth
wide, without peristome, about two-thirds as broad as the shell. (Compare Lithomitra, PL 79.)

Dimensions. — Shell 0'09 long, 0'045 broad ; mouth 0-03 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; also fossil in Barbados.

8. Cyrtocalpis ovulum, n. sp.

Cijrtocalpis obliqua, var. ovulum, Haeckel, 1862, Monogr. d. Radiol., p. 286, Taf. v. fig. 3.

Shell smooth, broad, ovate, with very numerous and small regular circular pores, quincuncially
disposed, twice as broad as the bars. Mouth without peristome, about half as broad as the shell.
Dimensions. — Shell 0'09 long, 0'047 broad; mouth 0'04 broad.
Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific, surface.

9. Cyrtocalpis obliqua, Haeckel.

Cyrtocalpis obliqua, Haeckel, 1862, Monogr. d. Radio]., p. 286, Taf. v. figs. 4-11.

Shell smooth, irregularly ovate, more or less oblique, variable in size and form, sometimes
nearly spherical, at other times subcylindrical. Pores subregular, circular, once or twice the
breadth of the bars. Mouth simple, without peristome, about half as broad as the shell.

Dimensions. — Shell 0'07 to O'l long, O'Oo to 0'08 broad ; mouth 0'03 to 0'04 broad.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific, surface.

1188 THE VOYAGE OF H.M.S. CHALLENGER.

10. Cyrtocalpis gromia, n. sp. (PI. 51, fig. 11).

Shell rough, ovate, very thick-walled, with subregular, circular pores of somewhat variable size.
The diameter of the internal, simple, subspherical cavity is five to six times as great as the thickness
of the wall. Mouth tubular, cylindrical, very narrow, only one-sixth as broad as the shell.

Dimensions. — Shell 0'16 long, Oil broad ; mouth 0'02 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Genus 530. Mitrocalpis,1 Haeckel, 1881, Prodromus, p. 427.

Definition. — A rchicorida with a double ovate or ellipsoidal shell, composed of
two parallel lattice-plates, which are connected by numerous beams. Apex without horn.

The genus Mitrocalpis and the following closely allied Spongocyrtis differ from the
four preceding genera of Archicorida in the complicated structure of the shell-wall,
which in the former is double, in the latter spongy. The mouth is in both genera
constricted, narrow, and the apex without a horn. Mitrocalpis has been derived
probably from Cyrtocalpis in the same way as Peripyramis from Bathropyramis, by
development of spines on the surface of the shell, which at equal distances from the
latter become connected by branches, thus forming an outer envelope.

1. Mitrocalpis palliata, n. sp.

Shell ellipsoidal, large, one and a third times as long as broad. Inner shell very thin-walled, with
irregular, polygonal pores of very variable size and form. From its nodal points there arise numerous
bristle-shaped radial beams, about as long as the diameter of the mouth, which are connected at equal
distances from the surface by delicate threads, forming the outer enveloping shell. The surface of
the latter is smooth. The thin bars of the inner shell are twice to four times as broad as those of
the outer. Mouth about one-seventh as broad as the shell, with a short tubular peristome.

Dimensions. — Shell O35 long, 0'27 broad ; mouth 0'04, distance of both shells 0'037.

Habitat. — Central Pacific, Station 271, surface.

Genus 531. Spongocyrtis? Dunikowski.

Spongocyrtis, Dunikowski, 1882, Denkschr. d. k. AkaJ. d. Wiss. Wien., vol. xlv. p. 31.
Definition. — Archicorida with a spongy ovate shell, the wall of which is
composed of irregular spongy wicker work. Apex without horn.

The genus Spongocyrtis differs from most other Monocyrtida in the spongy
structure of the shell, which is found in only very few other genera of C y r t o i d e a,
e.g., in Spongopyramis and Spongomelissa. It has been derived either from the similar

1 Mitrocalpis = Turban basket ; ftir^tt, xaxWf. ! Spongocyrtis^ Spongy basket ; avayytf,

REPORT ON THE RADIOLARIA. 1189

Cyrtocalpis by development of irregular spongy wickerwork on the surface of the simple
lattice-shell ; or from Arachnocalpis (PI. 98, fig. 13) by loss of the peristome.

1. Spongocyrtis mantis ovis, Dunikowski.

Spongocyrtis mantis ovis, Duuikowski, 1882, Denkschr. d. k. Akad. d. Wiss. Wien., vol. xlv.
p. 31, Taf. vi. figs. 67, 68.

Shell broad, ovate, rough, spongy, thick-walled ; length to the breadth = 4:3. Spongy frame-
work very dense and dark, with very small roundish pores. Mouth constricted, with a short
tubular peristome, about one-third as broad as the shell.

Dimensions. — Shell 0'35 long, 0'26 broad ; mouth 0'08 broad.

Habitat. — Fossil in the Alpine Lias (Schafberg bei Salzburg, Dunikowski).

2. Spongocyrtis arachnoides, n. sp.

Shell ellipsoidal, spiny, spongy, thin-walled ; length to the breadth = 3:2. Spongy frame-
work loose and delicate, with irregular polygonal meshes and arachnoidal thread-like bars. Mouth
constricted, without peristome, about one-fifth as broad as the shell. (Very similar to Arachnocalpis
ellipsoides, PI. 98, tig. 13, but without corona around the mouth.)

Dimensions. — Shell 0'32 long, 0'21 broad; mouth 0'04 broad.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

Subfamily 2. AKCHICAPSIDA, Haeckel, 1881, Prodromus, p. 428.

Definition. — C yrtocalpida, with the basal mouth of the shell fenestrated
(vel Monocyrtida eradiata clausa).

Genus 532. Halicapsa,1 Haeckel, 1881, Prodromus, p. 429.
Definition. — A rchicapsida with an apical horn.

The genus Halicapsa, and the following closely allied Archicapsa, represent
together the small subfamily of Archicapsida, or of those Cyrtocalpida, in which the
basal mouth of the simple shell is closed by a lattice plate. This may be the original
state of this family, if it is derived from the Circospyrida (Circospyris, Dictyospyris)
by loss of the sagittal constriction and the primary ring. But it is also possible that the
Archicapsida have been partly derived from the Archicorida by secondary fenestration
of the open mouth. The genus Halicapsa may be easily confounded with the similar
Ellipsid Lithapium (compare p. 303, PI. 14, figs. 8—10). The skeleton of both genera
may be perfectly similar, the only distinction being the structure of the central capsule,
which in Halicapsa is that of the MONOPYLEA, in Lithapium that of the PERIPYLEA.

1 Halicapsa = Sea-capsule ; ix;, na^et.

1190 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 1. Calpocapsa, Haeckel.
Definition. — Surface of the shell smooth or rough, but not spiny.

1. Halicapsa lithapium, n. sp. (PI. 97, fig. 6).

Shell pear-shaped, rough, one and a half times as long as hroad. Pores subregular, circular,
twice as broad as the bars. Basal plate with four larger ovate cortinar pores (two larger cardinal
and two smaller jugular), and with six smaller peripheral pores (fig. 6). Horn of the apex three-
sided pyramidal, stout, half as long as the shell.

Dimensions. — Shell 016 long, 01 broad; horn 0'08 long.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

2. Halicapsa triglochin, n. sp. (PI. 53, figs. 3, 4).

Shell ovate, rough, a little longer than broad. Pores regular, circular, hexagonally framed, of
the same breadth as the bars. Basal plate (fig. 4) without larger pores. Horn pyramidal, stout,
about half as long as the shell, with three short, horizontally divergent secondary spines at the base
(possibly remnants of three original cortinar feet ?)

Dimensions. — Shell Oil long, 0'09 broad; horn 0'06 long.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Halicapsa prunoides, n. sp.

Shell pear-shaped, tuberculate, a little longer than broad. Pores irregular, roundish, of different
sizes. Basal plate with four larger and six smaller pores. Horn pyramidal, stout, about one-third
as long as the shell. (May belong perhaps to the similar Pruuoidea Lithapium, compare
p. 303 and PI. 14, figs. 8-10.)

Dimensions. — Shell 014 long, 012 broad ; horn 0'05 long.

Habitat. — Fossil in Barbados.

Subgenus 2. Echinocapsa, Haeckel, 1881, Prodromus, p. 429.
Definition. — Surface of the shell spiny, covered with thorns, papillae or larger spines.

4. Halicapsa papillata, n. sp.

Shell bottle-shaped, papillate, one and a half times as long as broad. Pores circular, much
larger in the middle part than towards the poles. The elevated frames between them bear on the

REPORT ON THE RADIOLARIA. 1191

nodal points large blunt conical papillae. Basal plate without larger pores. Horn three-sided
pyramidal, one-third as long as the shell, gradually passing into the slender neck of the bottle.

Dimensions. — Shell 0'22 long, 015 broad; horn 0'07 long.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

5. Halicapsa pyriformis, Haeckel.

1 Haliomma pyriforme, Bailey, 1856, Amer. Journ. Sci. and Arts, voL xxii. p. 1, pi. i. fig. 29.

Shell pear-shaped, a little longer than broad, covered with numerous short conical spines
Pores subregular, circular, of nearly equal size, twice as broad as the bars. Basal plate with four
crossed larger ovate pores (two larger cardinal and two smaller jugular pores). Horn stout
pyramidal, scarcely one-fourth as long as the shell.

Dimensions. — Shell 016 long, 014 broad ; horn 0'04 long.

Habitat. — Fossil in Barbados, living in the North Pacific (Kamtschatka) ?

6. Halicapsa hystrix, n. sp. (PI. 53, figs. 5, 6).

Shell pear-shaped, subspherical, a little longer than broad, with scattered stout pyramidal spines
about as long as the radius of the shell. Pores subregular, circular, three times as broad as the
bars. Basal plate (fig. 6) without larger pores. Horn very large, pyramidal, longer than the shell.

Dimensions. — Shell 01 long, 0'09 broad; horn 013 long.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms. «

Genus 533. Archicapsa,1 Haeckel, 1881, Prodromus, p. 428.
Definition. — A rchicapsida without apical horn.

The genus Archicapsa differs from the preceding Halicapsa in the absence of the
apical horn, and represents the simplest form among the Monocyrtida clausa, a simple,
ovate, or pear-shaped shell without any appendages. The characteristic structure of
the basal lattice-plate (with three or four large cortinar pores) makes it probable that
Archicapsa has been derived either from Halicapsa, by loss of the horn, or directly
from Dictyospyriy, by reduction of the sagittal ring and constriction.

1. Archicapsa triforis, n. sp. (PI. 53, figs. 1, 2).

Shell pear-shaped, smooth, one and a half times as long as broad. Pores subregular, circular,
of about the same breadth as the bars. Basal plate (fig. 2) with three very large pores, three times
as broad as the others (one odd sternal pore and two paired cardinal pores).

Dimensions. — Shell 0'09 long, OD6 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

1 Archicapsa = Primordial capsule ; ei^ix.»^a.

1192 THE VOYAGE OF H.M.S. CHALLENGER.

2. Archicapsa quadriforis, n. sp.

Shell ovate, rough, a little longer than broad. Pores subregular, circular, twice as broad as the
bars. Basal plate with four larger ovate cortinar pores (two smaller jugular and two larger

cardinal pores).

Dimensions. — Shell 012 to 015 long, 01 to 012 broad.

Habitat. — Central Pacific, Station 265 to 268, depth 2700 to 2900 fathoms.

3. Archicapsa nonaforis, n. sp.

Shell pear-shaped, thorny, one and a half times as long as broad. Pores regular, circular, small,
hexagonally framed, twice as broad as the bars. Basal plate with nine cortinar pores (three
larger alternating with three pairs of smaller pores, as in PL 87, fig. 2).

Dimensions. — Shell 014 long, 0'09 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Section II. DICYETIDA, Haeckel, 1862, Monogr. d. Radiol., pp. 280, 296.

Definition. — Cyrtoidea dithalamia, with two-jointed shell, being divided by a
transverse collar stricture into an apical joint (or cephalis) and a basal joint (or thorax).

Synopsis of the three Families and six Subfamilies of Dicyrtida.

Family LXIT. ( Mouth open, . -1- Sethopilida.

Tripocyrtida.
Three radial apophyses. ( Mouth closed, . • 2. Sethoperida.

Family LXIII. ( Mouth open, . • 3. Sethophormida.

Anthocyrtida.
Numerous radial apophyses. ( Mouth closed, . sthophain

Family LXFV. ( Mouth open, . • -5- Sethocorida.

Sethocyrtida.
No radial apophyses. ( Mouth closed, .

Family LX1I. TRIPOCYRTIDA, n. fam.

Sethopilida et Sethoperida, Haeckel, 1881, Prodromus, pp. 431, 433.

Definition. — Dicyrtida triradiata. (Cyrtoidea with a two-jointed shell,
divided by a transverse constriction into cephalis and thorax, and bearing three radial
apophyses.)

REPORT ON THE RADIOLARIA. 1193

The family Tripocyrtida, composed of the Sethopilida and Sethoperida of my
Prodromus, comprises those Cyrtoidea in which the lattice -shell is two -jointed and
bears three radial apophyses. The two subfamilies differ in the shape of the mouth,
which in the Sethopilida is a simple wide opening, but in the Sethoperida is closed
by a lattice-plate; the former are here divided into sixteen, the latter into eight
different genera. Though probably the two shell -joints are not truly homologous in
all Tripocyrtida, we call the first joint here, as in all Dicyrtida, the cephalis, and
the second joint the thorax.

Numerous Tripocyrtida, living as well as fossil forms, were formerly described by
Ehrenberg. His genera Dictyophimus, Clathrocanium, Lithomelissa, and Lychno-
canium belong to the Sethopilida, and have the mouth open; his genera Lithopera and
Lithochytris (partly) belong to the Sethoperida, and have the basal mouth closed by a
lattice-plate. Many of these Tripocyrtida belong probably to the oldest forms of
Dicyrtida, are nearly related to the Phormospyrida, and therefore of special phylogenetic
interest, as was demonstrated by Biitschli (1882, loc. cit., pp. 514—519). This
near relation to certain Spyroidea (Tripospyris, Acrospyris, &c.) is particularly
striking in some forms of Clathrocanium, Lithomelissa, &c. Some other Tripocyrtida
seem to possess a closer relation to certain Plectoidea (Plagoniscus, Plectaniscus],
so mainly some forms of Tripocyrtis and Dictyophimus.

The cephalis, or the first joint of the shell, corresponds usually to the whole shell
of the Zygospyrida and of numerous Monocyrtida, and exhibits various modifications
of shape, which have been already described in these latter families. It is usually
subspherical or hemispherical and armed with an apical horn. In a small number
of genera the horn is lost, in some other genera multiplied. The cephalis is separated
from the thorax not only externally by the collar constriction, but commonly also
internally by a transverse horizontal fenestrated septum, which usually exhibits three
or four characteristic cortinar pores. The central capsule, originally enclosed in the
cephalis, develops usually three or four large pear-shaped csecal sacs which pass through
the cortinar pores and depend into the thorax (PI. 55, figs. 2—11 ; PI. 60,
figs. 3-7, &c.).

The thorax in this family exhibits a great variety of interesting modifications,
mainly in the development of the three radial apophyses arising from it. These may
be either enclosed in the wall of the thorax as ribs, or arise as free wings, very often
prolonged over the mouth as three terminal feet. Finally the three terminal feet only
remain, whilst the original ribs are lost. The special ornamentation of these three
apophyses exhibits an extraordinary variety and elegancy of structure, and many Tripo-
cyrtida belong, no doubt, to the most graceful and admirable forms of NASSELLAEIA.

(ZOOL. CHALL. Exp. — PART XL. — 1886.) Rr 150

1194

THE VOYAGE OF H.M.S. CHALLENGER.

Synopsis of the Genera of Tripocyrtida.

a. Three tho- ["

racic ribs pro- Cephalis f *

longed into J *»& a horn. ( j-ee
three terminal |

feet. ^° horn, feet solid,

A. Three radial
ribs(orcortinar
rods) partly or
completely en-
closed in the
wall of the
thorax. No
latticed vertical
cephalic wings.

I. Subfamily

Sethopilida.
Terminal mouth of
the thorax a j
simple wide open-
ing.

Feet solid, .
Feetlatticed,

b. Three tho-
racic ribs pro-
longed into
three lateral
wings.

Thorax per- I With ho
fectly lat- {

ticed. ( No horn, .

Thorax with spongy frame-
work,

Thorax with three large
lateral holes between the
three ribs,

c. Three tho- \
racic ribs com- Peristome simple, smooth, .

pletely enclosed^ peristome with a corona of
m the wall of g iueS) _

the flat thorax. [

B. Three radial
ribs enclosed

in the wall of

the thorax and

connected with -

the cephalic

horn by three

latticed vertical

wings.

C. Three radial
beams (or cor-
tinar rods) per-
fectly free, not
enclosed in the

wall of the
thorax.

D. Three radial terminal feet on j jree£ soii(j;
the peristome (the three original >

lateral ribs are lost). j Feetlatticed,

l No frontal horn (fourspines),

a. 1 borax com- )

pletely latticed. 1 Witl1 frontal horn (five

I spines), .

b. Thorax with three large lateral holes between
the three ribs. No frontal horn, .

Three beams outside the thorax, arising freely
from the collar stricture (no cephalic hole),

Three beams inside the thorax. Cephalis with
a large apical hole,

Three divergent ribs (or cortinar
rods) enclosed either in the
wall or in the cavity of the
thorax.

Three ribs enclosed in the
lattice-wall of the thorax,

Three internal rods in the
cavity of the thorax,

II. Subfamily

Sethoperida.

Terminal mouth of «(
the thorax closed |
by a lattice-plate. |

Three divergent free lateral wings
(as prolongation of the three <
ribs) on the sides of the thorax.

( Cephalis
with horn,

wingg_

Three free terminal feet (on the
base of the thorax).

Three solid
lateral \
spines. [

| Three latticed
[ With horn,

[ Three feet solid,

Shell with-
out exter-
nal mantle,

Shell with an
arachnoidal
. mantle,

Three feet
latticed.

534. DictyopTiimus.

535. Tripocyrtis.

536. Sethopilium.

537. Lithomelissa.

538. Psilomelissa.

539. Spongomelissa.

540. Clathrocaniuin

541. Lamprodiscus

542. Lamprornitra.

543. Callimitra.

544. Clathromitra.

545. Clatkrocorys.

546. Eucecryphalun.

547. Amphiplecta.

548. Lychnocanium.
649. Lychnodidyum.

550. Sethopera.

551. Lithopera.

552. Micromelissa.
5i>3. Peromelissa.

554. Sethomelissa.

555. Tetrahedrina.

556. Sethochytris.

557. Clatlirolychnus,

KEPORT ON THE RADIOLARIA. 1195

Subfamily 1. SETHOPILIDA, Haeckel, 1881, Prodromus, p. 431.

Definition. — T ripocyrtida, with the basal mouth of the shell open (vel Dicyr-
tida triradiata aperta).

Genus 534. Dictyophimus,1 Ehrenberg, 1847, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 53.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three complete
thoracic ribs, prolonged into three solid divergent feet on the peristome. Cephalis with
an apical horn.

The genus Dictyophimus, comprising many common species, may be regarded as
the common ancestral form of all Sethopilida, and therefore also of the whole family of
Dicyrtida. The cephalis bears an apical horn, and the thorax three ribs, which are
prolonged over the open mouth into three solid feet. Dictyophimus may be derived
either from Euscenium or Peridium (Archiperida), dr from Tripospyris (Zygospyrida),
or from Plectaniscus (Plectanida), by development of lattice-work between the three
terminal feet, which therefore become thoracic ribs.

Subgenus 1. Dictyophimium, Haeckel.

Definition. — Shell smooth or rough, without prominent spines on the edges of the
three thoracic ribs. (Commonly one single horn on the cephalis.)

1. Dictyophimus sphcerocephalus, n. sp. (PI. 57, fig. 10).

Shell smooth, with a deep collar stricture, separating two joints of nearly equal size. Cephalis
subglobular, rough, with a stout pyramidal horn of half the length, and regular, circular, hexagonally
framed pores. Thorax nearly three-sided prismatic, smooth, with three stout, little divergent or
nearly parallel ribs, which are prolonged into conical subvertical feet half as long. Thoracic
pores irregular, roundish.

Dimcnsiom. — Cephalis O08 long, 0'08 broad; thorax 0'08 long, O08 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Dictyophimus tripus, Haeckel.

Dictyophimus tripus, Haeckel, 1862, Monogr. d. Radio!., p. 306, Taf. vi. fig. 1.

Shell with a slight collar stricture, separating two joints of slightly different size. Cephalis nearly
ellipsoidal, large, with a slender conical horn of the same length. Thorax truncate three-sided

1 Dictyophimus = Net goblet ;

1196 THE VOYAGE OF H.M.S. CHALLENGER.

pyramidal, with three strongly divergent ribs, which are prolonged into three slender conical feet of
about the same length. Pores irregular, roundish, of variable size.

Dimensions. — Cephalis 0'032 long, 0'028 broad ; thorax 0'34 long, 0'064 broad.

Habitat. — Mediterranean (Messina), Atlantic (Canary Islands), surface.

3. Dictyophimus plectaniscus, n. sp. (PL 61, figs. 8, 9).

Shell flat, pyramidal, smooth, with distinct collar stricture. Cephalis hemispherical, with a
conical horn of the same length and numerous small regular pores. Thorax flat, triangular,
pyramidal, with three widely divergent ribs, which are prolonged into three cylindrical feet of the
same length. Thoracic pores fifteen, very large, subregular, roundish, disposed in two transverse
girdles, the inner with six, the outer with nine pores ; five pores between every two ribs.

Dimensions. — Cephalis 0'04 long, 0'06 broad ; thorax 0'08 long, 018 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Dictyophimus craticula, Ehrenberg.

Dictyophimus craticula, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68,

Taf. v. figs. 4, 5.
Dictyophimus craticula, Butschli, 1882, Zeitschr. f. Wiss. Zool., vol. xxxvi. p. 515, Taf. xxxiii.

fig. 35.

Shell flat, pyramidal, very similar to the preceding species, but differing in the rudimentary horn,
which is smaller than half the cephalis, and in the length of the three cylindrical feet, which are
twice to three times as long as the shell. The nine inferior large pores of the thorax are twice to
three times as large as the six superior pores. The basal peristome is commonly thorny.
Dimensions. — Cephalis 0'04 long, 0'05 broad ; thorax 01 long, 0'2 broad.
Habitat. — Fossil in Barbados.

5. Dictyophimus pyramis, n. sp. (PI. 61, fig. 16).

Shell regular, pyramidal, with flat collar stricture. Eelative length of the two joints = 1:4,
breadth = 2 : 6. Cephalis hemispherical, with a stout pyramidal horn of the same length. Thorax
triangular pyramidal, with three prominent ribs, which are prolonged into three slender pyramidal
feet, half as long. Pores small and very numerous, subregular, circular.

Dimensions. — Cephalis 0'03 long, 0'05 broad ; thorax 01 long, 015 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

6. Dictyophimus challengeri, Haeckel.

Dictyophimus challengeri, Haeckel, 1878, Protistenreicfi, p. 47, fig. 35.

Shell campanulate, with sharp collar stricture. Eelative length of the joints = 1 : 3, breadth
= 1:4. Cephalis subspherical, with a stout pyramidal horn of twice the length, and numerous

REPORT ON THE RADIOLARIA. 1197

very small pores. Thorax nearly hemispherical, with three vaulted bosoms between the three decurrent
ribs, which are prolonged into three nearly parallel and vertical feet of about the same length. Pores
subregular, circular, of medium size. This species is very similar to Lychnodictyum challenyeri,
Haeckel, but differs in the smaller straight horn and the longer solid feet, which are not fenestrated.

Dimensions. — Cephalis 0'03 long, O04 broad ; thorax 0'09 long, 013 broad.

Habitat. — Tropical Atlantic, Station 347, surface.

7. Dictyophimus lasanum, n. sp. (PI. 61, fig. 5).

Shell nearly pear-shaped, with distinct collar stricture. Eelative length of the two joints =
1 : 3, breadth =1:3. Cephalis hemispherical, with a conical horn of the same length. Thorax
nearly spherical, on both poles truncate and constricted, with three decurrent curved ribs and
small regular circular pores. The prolongations of the ribs form three divergent pyramidal
straight feet, nearly as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'09 long, O09 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

8. Dictyophimus longipes, n. sp. (PL 61, fig. 3).

Shell three-sided pyramidal, with distinct collar stricture. Eelative length of the two joints = 1:4,
breadth = 2 : 6. Cephalis hemispherical, with a rudimentary pyramidal horn, scarcely one-fourth as
long ; and with small circular regular pores. Thorax with larger irregular pores, and three vaulted
bosoms between the three decurrent ribs, which are prolonged into three very long and slender
prismatic feet, S-shaped, curved, and twice to three times as long as the shell.

Dimensions. — Cephalis 0-02 long, 0-04 broad ; thorax 0'09 long, 0'13 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

9. Dictyophimus gracilipes, Bailey.

Dictyophimus gracilipes, Bailey, 1856, Amer. Journ. Sci. and Arts, vol. xxii. p. 4, pi. i. fig. 8.

Shell three-sided pyramidal, with a deep collar stricture. Eelative length of the two joints =
1:3, breadth = 1:4. Cephalis hemispherical, with a thin horn of the same length. Thorax with
three curved ribs, which are prolonged into three divergent angular feet of the same length. Pores
irregular roundish.

Dimensions. — Cephalis 0'02 long, 0-03 broad ; thorax 0'05 long, 0-08 broad.

Habitat. — North Pacific, Station 240, surface, Kamtschatka (Bailey).

10. Dictyophimus cortina, n. sp. (PI. 61, fig. 1).

Shell three-sided pyramidal, with distinct collar stricture. Eelative length of the two joints
= 1:3, breadth =1:4. Cephalis subspherical, with a pyramidal horn of half the length. Thorax

1198 THE VOYAGE OF H.M.S. CHALLENGER.

with much larger irregular roundish pores and three prominent ribs, which are prolonged into three
stout, club-shaped, strongly divergent feet of the same length. Mouth widely open, elegantly
coronate, with a circle of numerous small cilia.

Dimensions. — Cephalis O02 long, O03 broad; thorax 0'06 long, 0'08 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

11. Dictyophimus arabicus, Haeckel.

Lychnocanium arabicum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 296,
Taf. x. fig. 3.

Shell smooth, three-sided pyramidal, with deep collar stricture. Kelative length of the two joints
= 1:3, breadth = 1:4. Cephalis subspherical, with a slender horn of the same length. Thorax
with much larger, irregular roundish pores, and three widely divergent ribs, which are prolonged
into three slender, somewhat recurved feet of about the same length.

Dimensions. — Cephalis 0'02 long, 0'02 broad; thorax 0'07 long, 0'09 broad.

Habitat. — Indian Ocean, Zanzibar (Pullen), depth 2200 fathoms.

12. Dictyophimus platycephalus, n. sp. (PI. 60, figs. 4, 5).

Shell smooth, flat, three-sided pyramidal, with distinct collar stricture. Kelative length of the two
joints =1:3, breadth = 3:9. Cephalis flat, cap-shaped, three times as broad as long, with a slender
conical horn of the same length. Thorax flatly vaulted, with much larger, irregular roundish, double-
edged pores, and three widely divergent ribs, which are prolonged into three slender conical feet of
the same length. Central capsule in the cephalis flat, discoidal, with a discoidal nucleus of half
the size, and with four large pear-shaped ctecal sacs depending into the thorax, each of which
contains a large oil globule (fig. 4).

Dimensions. — Cephalis 0'02 long, 0'07 broad ; thorax 0'06 long, 018 broad.

Habitat. — North Atlantic, Canary Islands (Lanzerote), Haeckel, surface.

18. Dictyophimus brandtii, n. sp. (PI. 60, fig. 6).

Shell smooth, flat, three-sided pyramidal, with deep collar stricture, very similar to the preced-
ing species. Eelative length of the two joints = 1:3, breadth =2:7. Cephalis hemispherical, with a
slender conical horn of twice the length. Thorax flatly vaulted, with irregular polygonal pores and
thin bars ; and with three widely divergent ribs, which are prolonged into three slender prismatic
feet of thrice the length. In fig. 6 the shell is seen from the base and exhibits very distinctly
the collar septum with its four large meshes, two minor jugular and two major cardinal pores.

Dimensions. — Cephalis 0'03 long, 0-07 broad ; thorax 0'08 long, 0'2 broad.

Habitat. — North Pacific, Station 236, surface.

REPORT ON THE RADIOLARIA. 1199

14. Dictyophimus lucerna, Haeckel.

Lychnocanium lucerna, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 6 ; Abhandl. d. k. Akad. d.

Wise. Berlin, 1875, p. 80, Taf. viii. fig. 3.
Lychnocanium lucerna, Haeckel, 1862, Monogr. d. Radiol., p. 311.

Shell smooth, three-sided pyramidal, with slight collar stricture. Eelative length of the two
joints = 1:4, breadth = 1:4. Cephalis hemispherical, with a thick conical horn of twice the length.
Thorax with small regular, circular pores and three flat sides ; between these arise three rounded
ribs, which are prolonged into three short, conical, divergent feet, one-third as long as the thorax.

Dimension. — Cephalis 0'02 long, 0'025 broad ; thorax 0'08 long, 0'08 broad.

Habitat. — Fossil in Barbados.

15. Dictyophimus hamosus, Haeckel.

Lychnocanium hamosum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78,
Taf. vii. fig. 9.

Shell pear-shaped, rough, with deep collar stricture. Eelative length of the two joints = 1 :2,
breadth = 1:3. Cephalis subglobular, with a conical horn of twice the length. Thorax with small,
regular, circular pores, and with three prominent ribs, prolonged into three vertical prismatic feet,
which are about as long as the shell, parallel or a little convergent towards the distal end, with
recurved teeth or hooks at the lateral edges.

Dimensions. — Cephalis 0-02 long, 0'02 broad ; thorax 0'04 long, 0'06 broad.

Habitat. — Fossil in Barbados.

16. Dictyophimus tridentatus, Haeckel.

Lychnocanium tridentatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80,
Taf. vii. fig. 4.

Shell smooth, three-sided pyramidal, with deep collar stricture. Eelative length of the two
joints = 1:3, breadth =1:4. Cephalis subspherical, with a conical horn of the same length, and
some small accessory thorns. Thorax tetrahedral, with three smooth hyaline walls, bearing only a
single series of small pores on each side of the three prominent ribs, which are prolonged into three
strong prismatic curved feet of twice the length, with the convexity external. A group of small
pores and a strong triangular tooth at the base of each foot.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'06 long, 0'08 broad.

Habitat. — Fossil in Barbados.

Subgenus 2. Lamprotripus, Haeckel, 1881, Prodromus, p. 432.

Definition. — Shell spiny or thorny, with prominent spines on the edges of the three
thoracic ribs. (Commonly one larger and a few smaller horns or spines on the cephalis.)

1200 THE VOYAGE OF H.M.S. CHALLENGER.

17. .Dictyophimus triserratus, n. sp. (PI. 61, fig. 17).

Shell three-sided pyramidal, with slight collar stricture. Eelative length of the two joints =
1 : 3, breadth = 1:4. Cephalis small, subspherical, with a large pyramidal horn three times as long.
Thorax with much larger, irregular roundish, double-edged pores, and three prominent, serrate ribs,
which are prolonged into three pyramidal strongly divergent feet of the same length.

Dimensions. — Cephalis 0'02 long, 0'02 broad; thorax 0'06 long, O09 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

18. Dictyophimus bicornis, n. sp.

Shell thorny, with deep collar stricture. Eelative length of the two joints = 2:3, breadth = 2:3.
Cephalis nearly as large as the thorax, subglobular, with numerous small, circular pores, and two
divergent pyramidal horns of half the length (a major occipital and a minor frontal horn). Thorax
three-sided pyramidal, with larger irregular pores and three serrate ribs, which are prolonged into
three prismatic spiny feet of half the length. (Differs from the similar Dictyophimus sphccrocephalus,
PI, 57, fig. 10, mainly in the double horn and the spinulate feet.)

Dimensions. — Cephalis 0'05 long, 0'05 broad ; thorax 0'08 long, 0'07 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

19. Dictyophimus pocillum, Ehrenbcrg.

Dictyophimus pocillum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. v.
fig. 6.

Shell thorny, with distinct collar stricture. Relative length of the two joints =1:5, breadth = 1:5.
Cephalis nearly spherical, with numerous small conical spines. Thorax flat, three-sided pyramidal
with large, irregular, roundish pores, and three strong, widely divergent, spinulate ribs, which are
prolonged into three prismatic spinulate feet of the same length.

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax 015 long, 015 broad.

Habitat. — Fossil in Barbados.

20. Dictyophimus cienkowskii, n. sp. (PI. 60, fig. 1).

Lamprotripus sijuarrosus, Haeckel, 1881, Prodromus et Atlas.

Shell spiny, flatly pyramidal, with slight collar stricture. Relative length of the two joints = 1:3,
breadth =2:6. Cephalis flat, cap-shaped, three times as long as broad, with numerous bristle-
shaped spines three times as long. Thorax also spiny, with irregular, very large, polygonal meshes
and thin bars ; its three ribs prolonged into three very long and thin, widely divergent, prismatic
feet, bearing numerous long spines on the three edges.

Dimensions. — Cephalis 0'025 long, 0'05 broad; thorax 0'075 long, 015 broad.

Habitat. — North Pacific, Station 250, surface.

REPORT ON THE RADIOLARIA. 1201

21. Dictyophimus biitschlii, n. sp. (PL 60, fig. 2).

Lamprotripus Jiorridus, Haeckel, 1881, Prodromus et Atlas.

Shell spiny, flatly pyramidal, with deep collar stricture. Relative length of the two joints = 1:2,
breadth = 1:5. Cephalis subspherical, with numerous long, bristle-shaped spines and a larger ramified
horn. Thorax also spiny, flatly vaulted, with large, subregular, hexagonal meshes and thin bars ; its
three spiny ribs prolonged into three very long and thin, prismatic, widely divergent feet, twice to
four times as long as the thorax.

Dimensions. — Cephalis 0'04 long, 0'04 broad; thorax 0'08 long, 0'2 broad.

Habitat. — South Pacific, Station 284, surface.

22. Dictyophimus hertwigii, n. sp. (PL 60, fig. 3).

Lamprotripus spinosus, Haeckel, 1881, Prodromus et Atlas.

Shell spiny, flatly pyramidal, with sharp collar stricture. Relative length of the two joints = 1 : 2,
breadth = 1:5. Cephalis subspherical, with irregular roundish pores, numerous small spines and
a large, oblique, prismatic horn of the same length, bearing on its distal end a bunch of small
divergent spines. Thorax pyramidal, with larger irregular polygonal pores and thin bars ; its three
strong, widely divergent ribs spiny, straight, and prolonged into three prismatic slender feet of the
same length. Central capsule with three lobes depending into the thorax.

Dimensions. — Cephalis 0'04 long, 0'04 broad ; thorax 0'08' long, 0'2 broad.

Habitat. — Central Pacific, Stations 270 to 274, surface.

Genus 535. Tripocyrtis,1 n. gen.

Definition. — Sethopilida (vel Dicyrtida triradiata aperta) with three complete
thoracic ribs, prolonged into three latticed divergent feet on the peristome. Cephalis
with an apical horn.

The genus Tripocyrtis has been derived from the preceding Dictyophimus by com-
plete fenestration of the three basal feet, which throughout their whole length become
united by complete lattice- work. This genus is closely allied to Plectaniscus.

1. Tripocyrtis plagoniscus, n. sp. (PL 60, fig. 10).

Cephalis subspherical, with large, roundish meshes and a stout, three-sided pyramidal, irregularly
branched horn of twice the length. Thorax with a small number of large, irregular, polygonal
meshes and three stout curved ribs about as long as the cephalic horn.

Dimensions. — Cephalis O'OG long, OD7 broad ; thorax Oil long, 016 broad.

Habitat. — Central Pacific, Station 266, surface.

1 Tripocyrtis = Basket with a tripod ; r^'roi, xv^rif.

(ZOOL. CUALL. EXP. — PART XL. — 1886.) Rr 151

1202 THE VOYAGE OF H.M.S. CHALLENGER.

2. Tripocyrtis tripodiscus, n. sp.

Cephalis subspherical, with small, polygonal pores and a large, arborescent, vertical horn of thrice
the length, bearing numerous ramified branches. Thorax with three straight, widely divergent
ribs, of the same length as the horn, connected by a delicate, arachnoidal framework with irregular,
polygonal meshes.

Dimensions. — Cephalis 0'04 long, 05 broad ; thorax 012 long, 018 broad.

Habitat. — Central Pacific, Station 269, surface.

3. Tripocyrtis plectaniscus, n. sp. (PI. 60, fig. 9).

Cephalis subspherical, with small roundish pores, and a stout, three-sided pyramidal, denticulate
horn of the same length. Thorax with three little divergent and curved ribs, twice as long as the
horn, in the upper half with smaller, in the lower half with larger, polygonal, irregular meshes.

Dimensions. — Cephalis 0'05 long, 0'06 broad ; thorax 01 long, 012 broad.

Habitat. — Central Pacific, Station 264, surface.

Genus 536. Sethopilium,1 Haeckel, 1881, Prodromus, p. 431.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three complete
thoracic ribs, which are prolonged into three solid divergent feet on the peristome.
Cephalis smooth, without a horn.

The genus Sethopilium differs from its probable ancestral form Dictyophimus by the
complete loss of the cephalic horn, and of the collar septum between both joints,
which are only separated by the slight external collar stricture.

1. Sethopilium orthopus, n. sp. (PL 97, fig. 8).

Shell smooth, with sharp collar stricture. Eelative length of the two joints —5:4, breadth = 7:6.
Cephalis large, subspherical, with numerous regular circular pores, twice as broad as the bars.
Thorax with three stout, straight, widely divergent ribs, prolonged into three straight pointed feet
of the same length. Between every two ribs, in the centre of the collar stricture, a single large
triangular mesh, and beyond this three to six rows of smaller irregular meshes.

Dimensions. — Cephalis 0'05 long, 0-07 broad ; thorax 0'04 long, 0'06 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Sethopilium cyrtopus, n. sp.

Shell smooth, with sharp collar stricture. Eelative length of the two joints = 4: 5, breadth =
7:11. Cephalis hemispherical, with large irregular roundish pores, four times as broad as the bars.

1 Sethopilium = Small ienestrated hat ; aqfa, irihtw.

EEPORT ON THE RADIOLARIA. 1203

Thorax with three stout, curved, widely divergent ribs, prolonged into three cylindro-conical, curved
feet of twice the length, which are convex in the proximal half, concave in the distal half. Between
every two ribs, beyond the collar stricture, two large ovate meshes, and beyond this two rows of
smaller irregular meshes.

Dimensions. — Cephalis OD4 long, OD7 broad ; thorax 0'05 long, Oil broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Sethopilium macropus, n. sp. (PI. 97, fig. 9).

Shell smooth, with slight collar stricture. Eelative length of the two joints = 4:7, breadth = 6:13.
Cephalis hemispherical, with irregular double-contoured pores, about as broad as the bars. Thorax
with three very stout, curved, widely divergent ribs, prolonged into three curved, cylindrical, very
long feet, which are three to four tunes as long as the shell, and convex on the outside. Between
every two ribs, beyond the collar stricture, two large broad meshes, and beyond this two or three
rows of smaller meshes.

Dimensions. — Cephalis 0'04 long, 0'06 broad ; thorax 0'07 long, 013 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 537. Lithomelissa,1 Ehrenberg, 1847, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 54.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three free
lateral wings, or solid spines arising from the sides of the thorax. No terminal feet.
Cephalis with one or more horns.

The genus Lithomelissa, containing numerous and widely distributed forms, may like
Dictyophimus be regarded as one of the most primitive and ancient forms of Dicyrtida.
It differs from the latter by the lateral (not terminal) position of the three thoracic feet,
and may be derived either from Dictyophimus (by secondary development of intrapedal
network towards the mouth, on the inside of the three feet) or directly from Tripo-
spyris by similar formation of thoracic network beyond the collar stricture, outside the
base of the three divergent feet and pierced by the latter. As the species of this genus
are numerous, it may perhaps be better to divide it into two or three genera : Acromelissa,
with a single horn, Micromelissa, with two horns, and Sethomehssa, with three or more
horns.

Subgenus 1. Acromelissa, Haeckel, 1881, Prodromus, p. 431.
Definition. — Cephalis with a single occipital horn.

1 Lithomelissa •= Stone bee ; X/do?, ft&iavu.

1204 THE VOYAGE OF H.M.S. CHALLENGER.

1. Lithomelissa macroptera, Ehrenberg.

Lithomelissa macroptera, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p.78, Taf. iii.
figs. 9, 10.

Shell smooth, with distinct collar stricture, llelative length of the two joints = 4: 5, breadth
= 3:4. Cephalis ovate, with a stout, excentric, vertical, pyramidal horn of the same length. Thorax
little larger, ovate, truncate. Both joints with very small and scattered pores. Three divergent
ribs arise from the base of the cephalic horn, and are prolonged over the major part of the thorax ;
their under free part arises from the middle part of the thorax and is as long as the horn, straight,
pyramidal. Mouth truncate, little constricted.

Dimensions. — Cephalis 0'04 long, 0'03 broad; thorax 0'05 long, 0'04 broad.

Habitat. — Fossil in Barbados.

2. Lithomelissa ehrenbergii, Blitschli.

Lithomelissa ehrenbergii, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 517,

Taf. xxxiii. fig. 2 la, b.
Lithomelissa macroptera, var., Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78,

Taf. iii. fig. 8.
(?) Lophophxna capita, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. viii.

% 6.

(?) Loplwplixna galeata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. viii.
fig. 12.

Shell rough, with distinct collar stricture. Eelative length of the two joints = 4:2, breadth = 3:4.
Cephalis ovate, with a stout excentric, oblique, pyramidal horn of half the length. Thorax little
shorter, truncate, conical. Both joints with regular circular pores, of the same breadth as the bars.
Three divergent conical feet, as long as the cephalis, arise below the collar stricture. Mouth
truncate, not constricted.

Dimensions. — Cephalis 0'08 long, 0'06 broad ; thorax 004 long, 0'08 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; fossil in Barbados.

3. Lithomelissa macroceras, n. sp.

Shell spiny, with sharp collar stricture. Eelative length of the two joints = 5:7, breadth = 5:6.
Cephalis spherical, with a large pyramidal horn of twice the length. Thorax little longer, ovate,
truncate. Both joints with regular circular pores, three times as broad as the bars. Three divergent
pyramidal feet, twice as long as the cephalis, arise from the middle part of the thorax. Mouth
constricted, half as broad as the thorax.

Dimensions. — Cephalis 0-05 long, 0-05 broad ; thorax 0'07 long, 0'06 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Lithomelissa mitra, Biitschli.

Lithomelissa mitra, Biitschli, 1881, Zeitschr. f. wiss. Zool., p. 518, Taf. xxxiii. fig. 24.

Shell smooth, with distinct collar stricture. Eelative length of the two joints = 5:4, breadth = 4:5.
Cephalis ovate, with a slender, straight, vertical, pyramidal horn of the same length. Thorax ovate,

REPORT ON THE RADIOLARIA. 1205

truncate, of about the same size. Both joints with very small and numerous pores, as broad as
the bars. Three feet arising from the middle part of the thorax, very small, rudimentary,
pyramidal, about as long as broad. Mouth truncate, little constricted.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax O04 long, 0'05 broad.

Habitat. — Fossil in Barbados.

5. Lithomelissa pycnoptera, n. sp.

Shell rough, papillate, with slight collar stricture. Relative length of the two joints = 1 :3,
breadth = 1:3. Cephalis small, hemispherical, with very small pores and- a slender, straight, conical
horn of twice the length. Thorax subconical, with regular circular, hexagonally framed pores, as
broad as the bars. From its lower half arise three divergent, very strong feet, pyramidal, as long
as the thorax, and three times as long as broad.

Dimensions. — Cephalis 0'03 diameter, thorax 01 diameter.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

6. Lithomelissa microstoma, n. sp.

Shell papillate, with slight collar stricture. Relative length of the two joints = 1:5, breadth = 1 : 5.
Cephalis small, hemispherical, with a conical horn of twice the length. Thorax subspherical, with
subregular circular pores, three times as broad as the bars. From its middle part arise three
divergent, stout, conical feet, of half the length, and twice as long as broad. Mouth small, strongly
constricted, one-fourth to one-third as broad as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 015 diameter.

Habitat. — Fossil in Barbados.

7. Lithomelissa amphora, Stohr.

Lithomelissa amphora, Stohr, 1880, Palseontograph, vol. xxvi. p. 100, Taf. iii. fig. 11.

Shell smooth, with sharp collar stricture. Relative length of the two joints = 1:5, breadth = 2:4.
Cephalis small, hemispherical, with a cervical horn of the same length. Thorax ovate, with small
regular circular pores, twice as broad as the bars. From its upper half arise three divergent, slender,
conical feet, only one-fourth as long. Mouth constricted, with a hyaline peristome, half as broad as
the thorax.

Dimensions. — Cephalis 0'013 long, 0'026 broad ; thorax 0'063 long, 0'053 broad.

Habitat. — Fossil in tertiary rocks of Sicily ; Grotte (Stohr).

Subgenus 2. Micromelissa, Haeckel, 1881, Prodromus, p. 433 (sensu emendato).

Definition. — Cephalis with, two divergent horns, a superior occipital horn and an
inferior frontal horn.

1206 THE VOYAGE OF H.M.S. CHALLENGER.

8. Lithomelissa thoracites, Haeckel.

Litlwmelissa thoracites, Haeckel, 1862, Monogr. d. Radiol., p. 301, Taf. vi. figs. 2-8.
Lithomelissa tJwracites, R. Hertwig, 1879, Organism, d. Radiol., p. 76, Taf. viii. fig. 1.

Shell smooth, with deep collar stricture. Cephalis ovate, with two divergent, slender, conical
horns, of about half the length ; a major oblique occipital horn on the posterior face, and a minor,
nearly horizontal horn above the collar stricture, on the anterior face. Thorax about as large as
the cephalis, truncate, ovate. Pores of both joints irregular, roundish, of different sizes. From the
upper half of the thorax, below the collar stricture, there arise three slender, conical divergent feet,
about as long as the cephalis. Mouth truncate, wide open, not constricted. On the numerous
varieties of this common species compare my Monograph, on the structure of the ovate central
capsule (enclosed in the cephalis), Hertwig, loc. cit.

Dimensions. — Cephalis 0/05 to 0'06 long, 0'04 to 0'05 broad ; thorax 0'03 to 0;05 long, 0'05 to
0-07 broad.

Habitat. — -Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, surface.

9. Lithomelissa mediterranea, J. Miiller.

Lithomelissa mediterranea, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 45, Taf. vi.

fig. 11.
Lithomelissa meJiterranea, Haeckel, 1862, Monogr. d. Radiol., p. 302.

Shell smooth, with sharp collar stricture. Relative length of the two joints = 4:5, breadth = 4:5.
Cephalis campanulate, conical, with two divergent small conical horns, a major occipital subvertical
horn near the summit, and a minor sub-horizontal frontal horn near the collar stricture. Thorax
truncate, ovate, little larger than the cephalis. From its lower part there arise three short conical,
divergent feet, scarcely half as long as the cephalis (in Miiller's figure one of them is seen
shortened, opposite to the frontal horn). Pores irregular, roundish, much smaller in the cephalis
than in the thorax. Mouth wide open, not constricted.

Dimensions. — Cephalis 0'04 diameter, thorax O05 diameter.

Habitat. — Mediterranean (French shore), J. Miiller, surface.

10. Lithomelissa bicornis, Ehrenberg.

Lithomelissa bicornis, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. ii.
fig. 7.

Shell smooth, with deep collar stricture. Eelative length of the two joints = 1:3, breadth = 1:2.
Cephalis hemispherical, with two divergent, stout and straight, pyramidal horns ; a larger occipital
horn sub-vertical near the summit, and a smaller oblique frontal horn near the collar stricture.
Thorax subspherical, twice as large, with larger irregular, roundish pores. From its lower half there
arise three divergent curved pyramidal feet of about the same length. Mouth constricted, only one-
third as broad as the thorax.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'06 diameter.

Habitat. — Atlantic, Stations 348 to 353, surface.

EEPORT ON THE KADIOLARIA. 1207

11. Lithomelissa haeckelii, Biitschli.

Lifhomelissa haeckelii, Butschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 517, Taf. xxxiii.
tig. 23, a, 6.

Shell rough, with sharp collar stricture. Eelative length of the two joints = 6:5, breadth = 6:7.
Cephalis subspherical, large, with two divergent horns, a very large, oblique pyramidal occipital horn
on the summit, and a very small frontal horn on the middle of the forehead. Thorax campanulate,
little larger than the cephalis, with regular circular pores of twice the breadth. From the upper
part of the thorax, below the collar stricture, there arise three stout, divergent, angular, semi-lunar
feet, about as long as the shell. Mouth wide open, not constricted.

Dimensions. — Cephalis 0'06 long, 006 broad ; thorax 0'05 long, 0-07 broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms ; fossil in Barbados.

12. Lithomelissa butschlii, n. sp. (PL 56, fig. 1).

Shell smooth, with slight collar stricture. Eelative length of the two joints = 5:6, breadth = 4:5.
Cephalis ovate, large, with two small conical horns, which are opposed nearly horizontally, in the
upper part of the cephalis; an anterior frontal and a posterior occipital horn. Thorax ovate,
truncate, little larger. Pores of both joints irregular, roundish, of very different sizes. From the
middle part of the thorax there arise three short conical divergent feet. (In the figured specimen
there were some accessory thorns ; in another specimen, found afterwards, the surface was quite
smooth, but the two horns and the three feet much larger, half as long as the cephalis.)

Dimensions. — Cephalis 0-05 long, 0'04 broad ; 0'06 long, 0'05 broad.

Habitat. — Central Pacific, Stations 266 to 274, depth 2350 to 2925 fathoms.

Subgenus 3. Sethomelissa, Haeckel, 1881, Prodromus, p. 431.

Definition. — Cephalis with three, four, or more horns, a primary occipital, a secondary
frontal, and one or more accessory parietal horns.

13. Lithomelissa corythium, Ehrenberg.

Lithomelissa corythium, Ehrenberg, 1875, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 78, Taf. iii.
fig. 12.

Shell smooth, with slight collar stricture. Eelative length of the two joints = 4:3, breadth = 4:5.
Cephalis campanulate, with three short conical horns on the summit. Thorax flat and wide. From
its upper part below the collar stricture, there arise three divergent, pyramidal feet, fenestrated
at the base, about as long as the shell. Mouth wide open. (The specimen figured by Ehrenberg
was an incomplete one.)

Dimensions. — Cephalis 0'04 in diameter, thorax 0'03 long, O'Oo broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; fossil in Barbados.

1208 THE VOYAGE OF H.M.S. CHALLENGER.

14. Lithomelissa decacantha, n. sp. (PI. 56, fig. 2).

Sethomeliesa decacantha, Haeckel, 1881, Prodromus et Atlas.

Shell smooth, with deep collar stricture, and with ten prismatic spines of nearly equal size
and similar form. Eelative length and breadth of the two joints about equal. Cephalis ovate, in
the upper half hyaline, in the lower half with few scattered pores ; in the equator with four
prismatic horns of the same length, which diverge upwards ; three of them are placed in the same
meridional planes as the three wings and the three feet of the thorax (one occipital and two
parietal); the fourth (frontal) horn is opposed to the occipital. Thorax campanulate, three-edged,
with three vertical prominent feet (directed downward) and three horizontal wings, arising from
their knees. Mouth wide open, not constricted.

Dimensions. — Cephalis 0'05 diameter ; thorax 0'05 long, O'OG broad.

Habitat. — Equatorial Atlantic, Station 347, surface.

I

Genus 538. Psilomelissa,1 Haeckel, 1881, Prodromus, p. 431.

Definition. — Sethopilida (vel Dicyrtida triradiata aperta) with three free
lateral wings, or solid spines arising from the sides of the thorax. No terminal feet.
Cephalis smooth, without a horn.

The genus Psilomelissa has the same formation of the shell as the nearly allied
preceding genus Lithomelissa, and may be derived from it by reduction and loss of the
cephalic horn. The cephalis is quite bare.

1. Psilomelissa galeata, Haeckel.

Didyocephalus galeatus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 289, Taf. vii.
fig. 25.

Shell smooth, with sharp collar stricture. Eelative length of the two joints = 5:3, breadth = 4:5.
Cephalis ovate, with numerous irregular, roundish pores. Thorax truncate, conical, with a few small
pores. From its upper part (below the collar stricture) there arise three thin, bristle-shaped,
widely divergent wings, about as long as the cephalis. Mouth widely open.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 0'03 long, 0'05 broad.

Habitat. — Western Tropical Pacific, Stations 200 to 225, surface.

2. Psilomelissa phalacra, n. sp.

Shell smooth, with deep collar stricture. Eelative length of the two joints = 5:6, breadth = 4:4.
Cephalis ovate, hyaline, with few small pores only in the lower third. Thorax cylindrical, truncate,
with small irregular, roundish pores. From its upper third there arise below the stricture three club-

1 Psilomelissa = Smooth bee ; i^Xo'j, fti^i/ra».

REPORT ON THE RADIOLARIA. 1209

shaped, nearly horizontally divergent wings, as long as the thorax. The cephalis and the three feet
are similar to those of Peromelissa phalacra, (PL 57, fig. 11); but the cylindrical thorax with
irregularly scattered pores is completely different, and exhibits a truncate, wide open mouth.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 0'06 long, 0'04 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

3. Psilomelissa hertwigii, Haeckel.

Lithomelissa hertwigii, Butschli, 1882, Zeitschr. f. wiss. Zool., p. 517, Taf. xxxiii. fig. 22, a, b.

Shell rough, with obliterated collar stricture. Length of the two joints = 4:4, breadth = 5:5.
Cephalis hemispherical. Thorax little larger, cylindrical. From its upper half there arise three
very strong pyramidal divergent wings, about as long as the shell. Pores of both joints very small
and numerous, circular. Mouth truncate, wide open.

Dimensions. — Cephalis 0'04 long, 0-05 broad ; thorax 0'04 long, 0'05 broad.

Habitat. — Fossil in Barbados.

4. Psilomelissa calvata, n. sp. (PI. 56, fig. 3).

Shell smooth, with sharp collar stricture. Length of the two joints = 7:5, breadth = 5:6.
Cephalis ovate, large, with subregular, circular, double-contoured pores. Thorax smaller, ovate,
with very irregular, roundish pores of different sizes. From its upper third there arise three conical,
slender, widely divergent spines or wings of the same length. (In fig. 3 the cephalis with the
three wings is alone represented.)

Dimensions. — Cephalis 0'07 long, 0'05 broad ; thorax 0'05 long, 0'06 broad.

HaUtat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

5. Psilomelissa sphcerocephala, n. sp.

Shell rough, with deep collar stricture. Length of the two joints =1:2, breadth = 1:3.
Cephalis spherical. Thorax cap-shaped, flat and broad. From its upper half there arise three pyra-
midal wings, half as long, fenestrated at the base and nearly horizontally divergent. Mouth con-
stricted, half as broad as the thorax.

Dimensions. — Cephalis 0'03 diameter; thorax 0'06 long, 0'09 broad.

HaUtat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 539. Spongomelissa,1 n. gen.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three free
lateral wings, or solid spines arising from the sides of the thorax. No terminal feet.
Cephalis with one or more horns.

1 Spongomelissa = Spongy bee ; oTrc'/yos, ^««A/au*.

(ZOOL. CHALL. EXP. — PART XL. — 1886). Rr 152

1210 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Spongomelissa differs from its ancestral genus Lithomelissa only in the
development of spongy framework in the shell-wall — a very rare production in the
Cyrtoidea (compare Peripyramis, p. 1162, and Spongocyrtis, p. 1188).

1. Spongomelissa spongiosa, Haeckel.

Lithomelissa spongiosa, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. pp. 519, 539, Taf.
xxxiii. fig. 25, a, b, c.

Shell of dense spongy structure, with a deep collar stricture. The subspherical cephalis and the
truncate abdomen of nearly equal size, both with irregular delicate spongy framework. Mouth
wide open. Cephalis with a large vertical apical and a small oblique frontal horn. Thorax with
three very stout, three-sided prismatic widely divergent lateral wings, which are covered with
numerous irregularly ramified branches ; the spongy framework arises by communication of the
delicate branches.

Dimensions. — Cephalis 0'04 long, 0'05 broad, thorax O04 long, 0'06 broad.

Habitat. — Fossil in Barbados.

Genus 540. Clathrocanium,1 Ehrenberg, 1860, Monatsber. d. k. preuss.
Akad, d. Wiss. Berlin, p. 829.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three prominent
lateral ribs on the thorax, alternating with three large holes (or thoracic gates). Cephalis
with a horn.

The genus Clathrocanium is nearly allied to Dictyophimus and Lithomelissa, and,
together with these two genera, may be regarded as surviving representatives of the
oldest and most primitive forms of Dicyrtida. It differs from the latter mainly in the
incomplete fenestration of the shell, three large interradial holes remaining between the
three perradial thoracic ribs. It may therefore be derived either from Euscenium or
from Tripospyris by the development of a terminal lattice-band between the three feet.
Clathrocanium may be divided into two different subgenera : Clathrocanidium, with
simple horn and smooth mouth, and Clathrocorona, with fenestrated horn and coronated
mouth.

Subgenus 1. Clathrocanidium, Haeckel.
Definition — Horn of the cephalis simple, not fenestrated. Peristome smooth.

1 Clathrocanium = Basket of network ; xAijfca, navmii.

REPORT ON THE RADIOLARIA. 1211

1. Clathrocanium squarrosum, Ehrenberg.

Clathrocanium squarrosum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287,
Taf. vii. fig. 5.

Cephalis campanulate, with irregular roundish pores and a pyramidal horn of the same length,
bearing at the apex three short branches. Length of the two joints 2 : 3, breadth = 2:6. Thorax
with three simple, prismatic, thin ribs, which are twice as long as the cephalis, separated by large
triangular holes and connected only at the distal end by a small triangular ring of delicate lattice-
work. Peristome smooth, wide, as broad as the thorax.

Dimensions. — Cephalis 0'04, long, 0'04 broad ; thorax 0'06 long, 012 broad.

Habitat. — Western Tropical Pacific (Philippine Sea), depth 3300 fathoms.

2. Clathrocanium sphcerocephalum, n. sp. (PI. 64, fig. 1).

Cephalis spherical, with regular circular pores and a prismatic horn of the same length, with
three serrated edges. Length of the two joints = 2:3, breadth 2:4. Thorax with three broad,
triangular, latticed, divergent ribs, which are separated by three large ovate holes (about as large as
the cephalis), and connected at the distal end by a broad fenestrated circular ring of regular
lattice-work (about six pores in its height). Peristome smooth, constricted, half as broad as
the thorax.

Dimensions. — Cephalis 0'04 long, 0'04 broad ; thorax 0-06 long, 0'08 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Clathrocanium coarctatum, Ehrenberg.

ClathTocanium coarctatum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287,

Taf. vii. fig. 6.
Lyclmocanium fenestratum, Ehrenberg, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 767.

Cephalis spherical, thorny, with regular circular pores and a simple pyramidal horn of the same
length. Length of the two joints = 2:3, breadth = 2:5. Thorax with three simple, prismatic,
little prominent ribs, which are separated by three large ovate holes (twice as long as the cephalis),
and connected below the prominent distal end by a narrow circular ring of delicate lattice-work.
Peristome smooth, wide, little narrower than the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'06 long, 01 broad.

Habitat. — Western Tropical Pacific (Philippine Sea), depth 3300 fathoms.

4. Clathrocanium triomma, n. sp. (PL 64, fig. 3).

Cephalis spherical, thorny, with regular circular pores, and a slender prismatic horn of twice the
length, bearing at its apex three short recurved branches. Length of the two joints = 2:4, breadth
= 2:5. Thorax with three broad prismatic, fenestrated ribs, which are separated by three large sub-

1212 THE VOYAGE OF H.M.S. CHALLENGER.

circular holes, and below the prominent distal end by a broad, triangular, roundish ring of subregular
lattice-work (with square pores). Peristome smooth, about half as broad as the thorax

Dimensions. — Cephalis 0'04 long, 0'04 broad; thorax O08 long, 01 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subgenus 2. Clathrocorona, Haeckel, 1881, Prodromus, p. 431.

Definition. — Horn of the cephalis fenestrated. Peristome on the margin of the
basal mouth with a corona of spines.

5. Clathrocanium diadema, n. sp. (PL 64, fig. 2).

Clathrocarona diadema, Haeckel, 1881, Prodromus, p. 431.

Cephalis hemispherical, thorny, with irregular roundish pores, and a large prismatic horn of twice
the length, the three edges of which are denticulate and fenestrated, each with a series of square
pores. Length of the two joints = 1:3, breadth = 2:4. Thorax thorny, with three broad fenestrated
divergent ribs, which are separated by three large ovate holes (twice as long as the cephalis) and have
their prominent distal ends connected below by a broad circular ring of lattice-work (with irregular
polygonal small meshes). Peristome wide, two- thirds as broad as the thorax, with a circular
corona of small square pores and alternating prominent small teeth.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'07 long, 0'09 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

6. Clathrocanium regince, n. sp. (PI. 64, fig. 4).

Clathrocorona regince, Haeckel, 1881, Prodromus, p. 431.

Cephalis hemispherical, with irregular roundish pores and a prismatic club-shaped horn of twice
the length, the three edges of which are denticulate and fenestrated. Length of the two joints
= 1:3, breadth = 1:4. Thorax thorny, with three broad triangular, fenestrated and nodulated
ribs, which are separated by three large ovate holes (twice as long as the cephalis) and have their
prominent distal ends connected below by a circular ring of lattice-work. Peristome constricted,
as broad as the thorax, with a corona of short spines.

Dimensions. — Cephalis 0'03 long, 0'04 broad; thorax 0'08 long, 0'12 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 541. Lamprodiscus, Ehrenberg, 1860, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 831.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three divergent
lateral ribs in the wall of the flat, conical, discoidal, or pyramidal thorax. Cephalis with
a horn. Peristome smooth, without corona of spines.

1 Lamprodiscus = Splendid disk ;

REPORT ON THE RADIOLARIA. 1213

The genus Lamprodiscus, and the following nearly allied Lampromitra, differ from
all preceding Sethopilida in the complete connection of the three thoracic feet by lattice-
work, so that they are imbedded in the thorax -wall as prominent ribs and are not
prolonged beyond the margin as free feet. The shell is commonly very flat, conical or
pyramidal, sometimes nearly discoidal. The margin of Lamprodiscus is simple, smooth.

1. Lamprodiscus monoceros, Ehrenberg.

Lamprodiscus monoceros, Ehrenberg, 1872, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 295, Taf. vil
fig 2.

Shell smooth, with deep collar stricture. Length of the two joints = 1:5, breadth = 1:8
Cephalis spherical, hyaline, without pores, with an oblique conical horn of the same length.
Thorax flat, campanulate, nearly hemispherical, with convex lateral outlines, and regular hexagonal
meshes, increasing gradually in size towards the mouth. Bars very thin. Peristome smooth.

Dimensions. — Cephalis 0'02 diameter; thorax 01 long, 016 broad.

Habitat. — Western Tropical Pacific (Philippine Sea), Station 200, surface.

2. Lamprodiscus coscinodiscus, Ehrenberg.

Lamprodiscus coscinodiscus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 295,
Taf. vii. fig. 3.

Shell smooth, with sharp collar stricture. Thorax of the same form and structure as in the
preceding species, differing from it mainly in the structure of the smooth circular margin, which is
composed of a ring of very small square pores. Length of the two joints = 1:4, breadth = 1:8.
Cephalis with small hexagonal pores, without horn or with a short rudimentary horn. Lateral
outlines of the campanulate thorax in the upper part concave, in the lower convex.

Dimensions. — Cephalis 0'02 diameter ; thorax 0'08 long, 016 broad.

Habitat. — Tropical Pacific, Stations 206, 224, 266, &c., surface.

3. Lamprodiscus tricostatus, n. sp.

Shell smooth, with deep collar stricture. Length of the two joints =1:3, breadth = 1:7.
Cephalis spherical, with an oblique conical horn of twice the length and small circular pores.
Thorax flatly, conical, twice as broad as high, with straight lateral outline, and regular hexagonal
meshes, increasing gradually in size towards the mouth ; bars very thin. Peristome or margin of
the basal mouth circular, smooth. Very similar to Theopilium tricostatum (PL 70, fig. 6), but without
abdomen. Differs from the two preceding species mainly in the conical form of the thorax and
the less delicate network.

Dimensions. — Cephalis 0'03 diameter; thorax 01 long, 0'2 broad.

Habitat. — Cosmopolitan, Mediterranean, Atlantic, Indian Pacific ; surface.

1214 THE VOYAGE OF H.M.S. CHALLENGER.

4. Lamprodiscus Icevis, Haeckel.

Eucecryphalus laivis, R Hertwig, 1879, Organism, d. Radiol,, p. 77, Taf. viii. figs. 6, 6rt, 65.

Shell smooth, with distinct collar stricture. Length of the two joints = 1:3, breadth = 1:6.
Cephalis subspherical, with small circular pores and an oblique conical horn of twice the length.
Thorax flat, pyramidal, twice as broad as long, with three strong, straight divergent edges and
subregular roundish pores. Peristome smooth.

Dimensions. — Cephalis 0'025 diameter; thorax 0'08 long, O16 broad.

Habitat. — Mediterranean (Messina), E. Hertwig, surface.

Genus 542. Lampromitra, Haeckel,1 1881, Prodromus, p. 431.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three divergent
lateral ribs in the wall of the flat conical or pyramidal thorax. Cephalis commonly
with a horn. Peristome with a corona of spines.

The genus Lampromitra differs from the preceding and nearly allied Lamprodiscus
only in the development of a dentated peristome, or an elegant corona of teeth around
the wide open mouth. It bears therefore to the latter the same relation that
Clathrocorona does to Clathrocanium.

1. Lampromitra coronata, n. sp. (PL 60, fig. 7, 7a).

Shell flat, conical, with slight collar stricture. Length of the two joints = 1:2, breadth = 2:7.
Cephalis hemispherical, with a conical oblique horn of twice the length, and small subregular
hexagonal pores. Thorax with larger, subregular, hexagonal meshes, six to eight times as broad as
the bars. Peristome or basal margin of the thorax circular, with a marginal ring of smaller polygonal
meshes and a triple coronal of short spines ; two external rings of short conical centrifugal spines,
and an internal ring of thin centripetal rods (fig. 7 a). In fig. 7 the shell is seen from below and
exhibits very distinctly the internal cross of the collar septum, composed of the four divergent
cortinar bars ; between the latter descend the four pear-shaped lobes of the central capsule (each
containing an oil globule), whilst the apical part of the capsule (with the nucleus) is hidden in the
large cap-shaped cephalis.

Dimensions. — Cephalis 0'03 long, 0'07 broad ; thorax 0'06 long, 0'2 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Lampromitra quadricuspis (PL 58, fig. 7).

Shell flat, conical, with sharp collar stricture. Length of the two joints =1 : 3, breadth = 2 : 10.
Cephalis hemispherical, with subregular circular pores and an oblique, conical, occipital horn of twice

1 Larnpromitra= Splendid turban;

REPORT ON THE RADIOLARIA. 1215

the length, bearing three divergent lateral branches, which are directed upwards, and correspond
to the three thoracic ribs. Further down, near the collar stricture, a short divergent frontal
horn arises. Thorax with irregular roundish pores of different sizes, three to six times as broad as
the bars. Peristome with a simple coronal of short, conical, divergent spines, about as long as the
diameter of the cephalis.

Dimensions. — Cephalis 0'02 long, OD4 broad ; thorax O06 long, 0'2 broad.

Habitat. — North Atlantic, Canary Islands, surface.

3. Lampromitra furcata, n. sp. (PI. 58, fig. 8).

Shell flat, conical, with deep collar stricture, very similar in form and structure to the preced-
ing species ; differs from it in the shape of the peristome and the armature of the cephalis, which
bears a conical, forked, occipital horn of the same length, and a small rudimentary divergent frontal
horn. Length of the two joints = 1:2, breadth =1:6. The four pores of the collar septum (two
larger cardinal and two smaller jugular) exhibit in this species a peculiar asymmetry (fig. 8). The
peristome bears a simple coronal of spines as long as the diameter of the cephalis. The major part
of them is forked, some irregularly branched.

Dimensions. — Cephalis O02 long, 0'03 broad; thorax 0'06 long, 018 broad.

Habitat.— South Pacific, Station 298, depth 2225 fathoms.

4. Lampromitra pyramidalis, n. sp.

Shell flat, pyramidal, smooth, with slight collar stricture. Length of the two joints = 1:4,
breadth = 1:9. Cephalis subspherical, with an oblique pyramidal horn of twice the length, and
small circular pores. Thorax with three strong, divergent, straight ribs and three flat triangular
sides between them, with subregular hexagonal pores, increasing in size towards the mouth.
Peristome with a simple coronal of large and numerous divergent, conical spines, half as long as the
shell.

Dimensions. — Cephalis O02 long, 0'02 broad ; thorax 0'09 long, 018 broad.

Habitat. — South Atlantic, Station 325, depth 2650 fathoms.

5. Lampromitra huxleyi, Haeckel (PI. 59, fig. 1).

Eucecryplialus huxleyi, Haeckol, 1879, Natiirl. Schopfungsgesch., Edit. vii. Taf. xvi. fig. 9.

Shell flat, conical, spiny, with slight collar stricture. Length of the two joints = 1:3, breadth
= 1:8. Cephalis hemispherical, with a short conical horn of the same length. Thorax with
irregular polygonal pores. Peristome with three coronals of divergent bristle-shaped spines ; the
first directed obliquely upwards, the second outwards, and the third nearly vertically, downwards ;
the bristles of the latter are much longer, about as long as the height of the shell.

Dimensions.— Cephalis 0'02 long, 0-02 broad; thorax OD6 long, 016 broad.

Habitat. — Australia (east coast), Station 169, surface.

1216 THE VOYAGE OF H.M.S. CHALLENGEE.

6. Lampromitra schultzei, Haeckel.

Eucecryphalus schultzei, Haeckel, 1862, Monogr. cl. Radiol., p. 309, Taf. v, figs. 16-19.

Shell flat, conical, smooth, with slight collar stricture. Length of the two joints = 1:3, breadth
= 1:8. Cephalis hemispherical, with a small conical horn of half the length, and very small
roundish pores. Thorax with three strong, straight ribs and irregular polygonal pores, which are
much larger in the middle part than in the upper or lower part. Peristome with a double
coronal of short, conical, divergent spines; the superior obliquely ascending, the inferior vertically
descending. (Named in honour of the late Professor Max Schultze, the illustrious histologist.)

Dimensions. — Cephalis OD25 diameter; thorax 0'07 long, 0'2 broad.

Habitat. — Mediterranean, Messina, surface.

7. Lampromitra arborescens, n. sp, (PI. 60, fig. 8, Set).

Shell flat, pyramidal, spiny, with sharp collar stricture. Length of the two joints =1:3,
breadth = 2 : 10. Cephalis cap-shaped, with an oblique, slender, conical horn of twice the length,
and small circular pores. Thorax with three slight almost obliterated ribs and three vaulted sides
between them, with irregular roundish pores. The three ribs are distinct in the proximal, not in the
distal part. Peristome with a double coronal of smaller squarish pores and numerous divergent
spines ; the larger spines are irregularly branched and as long as the diameter of the cephalis.

Dimensions. — Cephalis 015 long, 0'03 broad ; thorax 0'04 long, 0-2 broad.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

8. Lampromitra dendrocorona, n. sp. (PI. 58, fig. 9).

Shell flat, conical, with smooth surface and deep collar stricture. Length of the two joints
= 1:4, breadth = 2 : 10. Cephalis hemispherical, with a slender occipital horn of three times the
length, and a small divergent frontal horn. Thorax with three strong, prominent, straight ribs and
irregular polygonal meshes, increasing in size towards the mouth. Peristome with a dense coronal of
numerous short conical spines and twenty-four to thirty larger arborescent spines, longer than the
diameter of the cephalis.

Dimensions. — Cephalis 0'02 long, 0'04 broad ; thorax 0'08 long, 0'2 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 543. Callimitra,1 Haeckel, Prodromus, 1881, p. 431.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three vertical
latticed wings, which stretch between the three divergent lateral ribs of the thorax and
the vertical horn of the cephalis. No frontal horn.

1 Callimitra = Beautiful turban ; xdiMi.li, ft<Vj«.

REPORT ON THE RADIOLARIA. 1217

The genus Callimitra, and the two following nearly allied genera, Clathromitra and
Clathrocorys, form together a peculiar small group, the Callimitrida, living in the
Central Pacific, and differing from the other Sethopilida in some remarkable points,
derived perhaps directly from the Archiscenida, Archiscenium and Pteroscenium, by
the development of thoracic network between the three cortinar feet. In the centre of
the collar septum, where these feet are united, there arises a vertical free columella,
prolonged over the top of the cephalis as a free horn, and this horn is connected with
the three thoracic ribs by three vertical fenestrated wings.

1. Callimitra carolotce, n. sp. (PL 63, figs. 1, 7, 8).

Cephalis campanulate, conical, with irregular, polygonal pores, and a thin bristle-shaped apical
horn of the same length. Length of the two joints = 3:6, breadth = 2 : 6. Thorax in the upper
half with irregular network, in the lower half with parallel transverse bars ; in each of its three
•sides descend two convergent pairs of stronger, parallel, curved ribs, not confluent at the peristome.
Each of the three vertical wings with eight stronger ribs, three arising from the cephalis, five from
each foot. Dedicated to my dear mother Charlotte Sethe.

Dimensions. — Cephalis 0'07 long, 0'05 broad; thorax 015 long, 0'15 broad.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

2. Callimitra annce, n. sp. (PI. 63, fig. 2).

Cephalis campanulate, conical, with irregular, polygonal pores, and a thin bristle-shaped horn of
the same length. Length of the two joints = 1:2, breadth = 1:3. Thor&x nearly in its whole
extent with parallel transverse bars, which are crossed by two convergent systems of parallel
beams ; in each of its three sides descend four convergent pairs of stronger, parallel, curved ribs, not
confluent at the peristome. Each of the three vertical wings with six stronger ribs, three arising
from the cephalis, three from each foot. Dedicated to my dear first wife Anna Sethe.

Dimensions. — Cephalis 0'05 long, 0'05 broad ; thorax 0'12 long, 0'18 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Callimitra agnescs, n. sp. (PI. 63, fig. 5).

Cephalis pear-shaped, with irregular, scpuare pores, and a slender bristle-shaped horn twice
as long. Length of the two joints = 1:3, breadth = 1:5. Thorax in its whole extent with
parallel transverse bars, which are crossed by two converging and crossed systems of parallel
beams ; in each of its three sides descend five convergent pairs of stronger, parallel, curved ribs, the
two or three upper of which are crossed at the peristome. Each of the three vertical wings with
five stronger ribs, three arising from the cephalis and the horn, two from each foot. Dedicated to
my dear second wife Agnes Huschke.

Dimensions. — Cephalis 0'05 long, 0'05 broad; thorax 0'15 long, 0'22 broad.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

(ZOOL. CHALL. EXP. PART XL. 1880.) Rr 153

1218 THE VOYAGE OF H.M.S. CHALLENGER.

4. Callimitra elisabethee, n. sp. (PI. 63, fig. 6).

Cephalis nearly hemispherical, with irregular, square pores, and a strong prismatic horn thrice
the length. Length of the two joints =2:7, breadth = 2:9. Thorax in the upper third with
irregular network, in the lower two-thirds with parallel transverse bars, which are crossed by two
convergent systems of parallel beams ; in each of its three sides descend three convergent pairs of
stronger, parallel, curved ribs ; the two ribs of the uppermost pair are united and confluent in a
single odd rib in the lower half of the thorax. Each of the three vertical wings with seven
stronger ribs, three arising from the cephalis and the horn, four from each foot. Dedicated to my
dear elder daughter Elizabeth Haeckel.

Dimensions. — Cephalis 0'04 long, 0-05 broad; thorax 0'15 long, 0'2 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Callimitra emmce, n. sp. (PL 63, figs. 3, 4").

Cephalis campanulate, with irregular, polygonal pores, and very thin bars (of the same shape
as in the thorax) and with a thin bristle-shaped horn twice the length. Length of the three
joints = 3:6, breadth = 2 : 9. Thorax in its whole extent with an arachnoidal network, similar to that
in the cephalis and the three wings, composed of very numerous parallel threads, which are crossed
by two crossed diagonal systems of parallel threads. In each of the three sides of the thorax
descend five convergent pairs of stronger ribs, the three upper of which are crossed and form
large rhomboidal meshes. Each of the three vertical wings with ten stronger ribs, four arising
from the cephalis and each horn, six from each foot. Dedicated to my dear younger daughter
Emma Haeckel.

Dimensions. — Cephalis 0'07 long, 0'06 broad ; thorax 015 long, 0'22 broad,

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 544. Clathromitra,1 Haeckel, 1881, Prodromus, p. 432.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three vertical
latticed wings, which stretch between the three divergent lateral ribs of the thorax and
the vertical horn of the cephalis. The front of the latter is armed with a large frontal
horn.

The genus Clathromitra differs from the preceding similar Callimitra in the develop-
ment of a free frontal or sternal horn, a prolongation of" an internal obliquely ascending
rod, opposite to the caudal foot. Therefore the shell in this genus possesses five divergent
free spines, two cephalic horns, and three thoracic feet. The lattice-work of the three
vertical wings is not so delicate as in Callimitra.

1 Clathromitra = Lattice-turban ;

REPORT ON THE RADIOLARIA. 1219

1. Clathromitra pterophormis, n. sp. (PL 57, fig. 8).

Cephalis very large, hemispherical, about as long and half as broad as the three-sided pyramidal
thorax ; both with irregular, polygonal meshes. Apical horn three to four times as long as the frontal
horn and the three basal feet. All five spines three-sided prismatic, with nearly smooth edges.
Three lateral wings half as broad as the cephalis.

Dimensions. — Cephalis 0'05 long, 01 broad ; thorax 0'05 long, 015 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Clathromitra pentacantha, n. sp.

Cephalis large, hemispherical, half as long as the three-sided pyramidal thorax ; both with irre-
gular, roundish meshes. Apical horn of about the same length as the frontal horn, and twice as
long as the three basal feet, All five spines three-sided prismatic, with denticulated edges. Three
lateral wings about as broad as the cephalis.

Dimensions. — Cephalis 0'04 long, 0'08 broad ; thorax 01 long, 0'2 broad

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 545. Clathrocorys,1 Haeckel, 1881, Prodromus, p. 432.

Definition. — Sethopilida (vel Dicyrtida triradiata aperta) with three prominent
lateral ribs on the thorax, alternating with three large holes (or thoracic gates). The
three ribs are connected with the central apical horn of the eephalis by three vertical
latticed wings,

The genus Clathrocorys differs from the two preceding nearly allied genera in the
incomplete fenestration of the thorax, the three perradial ribs of which are separated by
three large interradial holes. It has therefore the same relation to Callimitra that
Clathrocanium bears to Dictyophimus.

1. Clathrocorys murrayi, n. sp. (PI. 64, fig. 8).

Cephalis pear-shaped, with irregularly square pores. From the centre of its base there arise four
strong, prismatic, radial beams of nearly equal size, the vertical, straight, cephalic horn being little
longer than the three divergent, somewhat curved feet. In the three meridional planes (between the
horn and each foot) a few rather thick branches arise, which by communication of the ramules form
the three vertical latticed wings; each wing with two large meshes, three to five meshes of medium size,
and three to four parallel arachnoidal rows of small, square, distal meshes. The three walls of the flat
pyramidal thorax (between every two feet) are formed in the upper part by squarish network

1 Clathrocorys = Lattice-helmet ;

1220 THE VOYAGE OF H.M.S. CHALLENGER.

similar to that of the cephalis, in the middle part by a single row of arches separated by thin
threads, and in the lower part by a narrow band of arachnoidal network. Dedicated to Dr. John

Murray.

Dimensions. — Cephalis 0'05 long, 0'05 broad ; thorax 0'0'04 long, 015 broad ; apical distance of
every two feet 015, of each foot and the horn 017.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Clathrocorys teuscheri, n. sp. (PL 64, fig. 10).

Cephalis pear-shaped, with irregular, square pores. From the centre of its base there arise seven
prismatic, radial beams of equal strength, supporting the lattice-work of the wall ; the single verti-
cal beam is prolonged into the apical horn ; six others lie in the three meridian planes (between the
horn and each foot) ; three ascending end in the wall of the cephalis, three descending are prolonged
into the three strong feet, which are longer than the horn. In each meridional plane there arise four
thicker and several thinner bars, which by communication of their ramules form the three latticed
wings ; each wing with a single very large mesh, two meshes of medium size, and a narrow marginal
band of small, square pores. The three walls of the flat pyramidal thorax are formed in the upper
part by squarish network similar to that of the cephalis, in the lower part by a narrow band of
the same ; between them a large hole. Dedicated to Dr. Eeinhold Teuscher.

Dimensions. — Cephalis 0'05 long, 0'04 broad; thorax 0'06 long, 015 broad ; apical distance of
every two feet 0'2, of each foot and the horn 0'2.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Clathrocorys giltschii, n. sp. (PI. 64, fig. 9).

Cephalis pear-shaped, with irregular, polygonal pores. From the centre of its base there arise
seven prismatic, radial beams of different strength ; the single vertical beam bears six lateral branches
(parallel to the three ascending supporting beams), and is prolonged into the apical horn ; six others
lie in the three meridional planes (between the horn and each foot) ; three weaker ascending beams
end in the wall of the cephalis, three stronger descending are prolonged into the three large diver-
ging feet, which are twice as long as the cephalic horn. The network of the three wings and of the
three-sided pyramidal thorax is about the same as in the preceding species, but much more developed ;
the marginal bands with the squarish network are much broader, and an arachnoidal wicker-work of
very thin thread-like bars fills out the large meshes. Dedicated to Mr. Adolf Giltsch.

Dimensions.- — Cephalis 0'04 long, 0'04 broad; thorax 012 long, 0'2 broad; apical distance of
every two feet 0'24, of each foot and the horn 0'2.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 546. Eucecryphalus,1 Haeckel, 1860, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 836.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three free collar

1 Eiicecryphalus=Nice net-cap ; £<T, zi

REPORT ON THE RADIOLARIA. 1221

wings or solid spines arising from the collar stricture, and freely prominent between the
horned cephalis and the flat conical thorax.

The genus Eucecryphalus, according to the restricted definition here given, com-
prises only those Sethopilida in which the three primary cortinar beams are perfectly
free divergent collar wings, i.e., free spines arising outside the shell from the collar
stricture, between the cephalis and thorax. The type of this genus (which I formerly
united with other Sethopilida) remains Eucecryphalus gegenbauri.

Subgenus 1. Eucyrtomphalus, Haeckel, 1881, Prodromus, p. 431.

Definition. — Peristome or margin of the ba*al mouth of the thorax smooth, without
marginal spines.

1. Eucecryphalus corocalyptra, n. sp.

Shell flatly conical, with slight collar stricture. Length of the two joints =1:3, breadth = 1:6.
Cephalis subspherical, with an oblique conical horn twice its length. Thorax conical, twice as
broad as long, with regular hexagonal meshes and straight lateral outlines. From the collar stricture
there arise three slender conical spines, about as long as the thorax, divergent downwards. Similar
to Corocalyptra, agnescc (PL 59, fig. 3), but without lumbar stricture and abdomen. Peristome or
basal margin of the mouth of the thorax smooth, simple.

dimensions. — Cephalis 0'03 diameter; thorax 0'09 long, 018 broad.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, surface.

2. Eucecryphalus halicalyptra, n. sp.

Shell flat, campanulate, with distinct collar stricture. Length of the two joints = 1 : 4, breadth
= 2 : 10. Cephalis hemispherical, with two divergent conical horns, a major occipital and a minor
frontal horn. Thorax with subregular hexagonal meshea and concavo-convex lateral outlines, cam-
panulate. From the collar stricture there arise three divergent bristle-shaped spines, nearly horizontal,
about half as long as the thorax. Peristome smooth, with a marginal coronal of small square
pores.

Dimtnsions.-Z-Gephalis 0'02 long, 0'04 broad ; thorax 0'08 long, 0'2 broad.

Habitat. — Central Pacific, Stations 266 to 274, surface.

Subgenus 2. Eucecryphalium, Haeckel.

Definition. — Peristome or margin of the basal mouth of the thorax dentate, with'
a coronal of marginal spines.

1222 THE VOYAGE OF H.M.S. CHALLENGER.

3. Eucecryphalus cuvieri, n. sp.

Shell flatly conical, with slight collar stricture. Length of the two joints = 1:8, breadth = 2:10.
Cephalis hemispherical, with an oblique pyramidal horn twice as long. Thorax with straight
outlines and regular hexagonal meshes, increasing in size towards the mouth. From the collar
stricture there arise three stout conical spines, half as long as the thorax, and diverging downwards.
Peristome with a ring of small square pores and alternate conical divergent spines. Differs from
the similar Clathrocyclas alcmence (PL 59, fig. 6), mainly in the simple apical horn and the possession
of the three collar fundamental spines.

Dimensions. — Cephalis O02 long, 0'03 broad ; thorax 015 long, 0'2 broad.

Habitat. — Tropical Atlantic, Station 342, depth 1445 .fathoms.

4. Eucecryphalus mulleri, n. sp.

Shell flatly campanulate, of nearly the same structure as and similar form to that of the preceding
species. Differs from it mainly in the considerable size of the cephalic horn and the three collar spines,
which are bristle-shaped and longer than the shell. Length of the two joints =1:4, breadth =
2 : 8. The peristome bears a double marginal ring of divergent conical spines, the upper being
directed upwards, the lower downwards.

Dimensions — :Cephalis 0'02 long, O04 broad ; thorax 0'08 long, 016 broad.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

.5. Eucecryphalus gegenbauri, Haeckel.

Eucecryphalus gegenlauri, Haeckel, 1862, Monogr. d. Radiol., p. 308, Taf. r. figs. 12-15.
Eucecryphalus gegenbauri, R. Hertwig, 1879, Organism, d. Radiol., p. 76, Taf. viii. figs. 5,
:5a, 56.

Shell flatly conical, campanulate, with slight collar stricture. Length of the two joints = 1 : 4,
breadth = 1:8. Cephalis .hemispherical, with a conical horn of the same length, and very small
pores.' Thorax about twice as broad as high, with large, subregular, hexagonal meshes, increasing in
size downwards. In the upper half of the thorax the meshes are filled up by an extremely delicate
arachnoidal network. From the collar stricture there arise three divergent bristle-shaped spines half
as long as the thorax. Peristome with a double coronal of small square pores (the inner smaller and
more numerous than the outer), and with a single coronal of divergent marginal spines. This
cosmopolitan species is rather variable.

Dimensions.— Cephalis 0"02 to 0'03 diameter; thorax 01 to 012 long, 0'02 to 0'25 broad.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, surface.

EEPORT ON THE EADIOLARIA. 1223

6. Eucecryphalus campanella, Haeckel.

Pterocodon campanella, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xix.
fig. 2.

Shell campanulate, conical, with sharp collar stricture. Length of the two joints = 1:3,
breadth = 1:2. Cephalis hemispherical, with a short conical horn half as long, and very
small pores. Thorax campanulate, as broad as high,' with large roundish meshes, increasing in size
downwards. From the collar stricture arise three strong, divergent, somewhat curved spines, nearly
as long as the thorax. Peristome with a coronal of ten to twelve strong, conical, marginal spines,
which are nearly parallel, directed downwards, a little curved, and half as long as the thorax.
In the complete specimen examined by me, the apical horn, the three lateral wings and- twelve
terminal feet were well preserved.

Dimensions. — Cephalis 0'02 to 0'03 diameter; thorax 0'06 to 0'07 long and broad.

Habitat. — Fossil in Barbados.

Genus 547. Amphiplecta,1 Haeckel, 1881, Prodromus, p. 424.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta) with three internal
thoracic ribs, enveloped by the network of the thorax. Cephalis with a large apical
opening, surrounded by a coronal of spines.

The genus Amphiplecta (or Amphicryphalus) comprises some very peculiar forms of
Sethopilida, probably widely remote from the other genera of this subfamily, and derived
directly from the Plectanida (compare above, p. 921). The cortinar tripodium, composed
of three feet divergent downwards, and one apical horn ascending upwards (in some
species also a second frontal horn) is here enclosed in the cavity of a two-jointed shell,
which exhibits two large openings, a smaller apical hole in the top of the cephalis, and a
larger terminal mouth on the thorax. There is no trace of a sagittal ring.

1. Amphiplecta amphistoma, n. sp.

Cephalis subspherical, spiny, with sharp collar stricture on the base ; its apical opening central,
surrounded by a coronal of twelve to eighteen short spines. Length of the two joints =7:8,
breadth = 6:20. Thorax flatly conical, armed with bristle-shaped spines. Meshes of the network
in both joints subregular, hexagonal, six to eight times as broad as the bars. Basal mouth bristly.

Dimensions. — Cephalis O07 long, 0'06 broad ; thorax 0'08 long, 0'2 broad.

Habitat. — Central Pacific, Station 274, surface.

2. Amphiplecta acrostoma, n. sp. (PI. 97, fig. 10).

Cephalis subspherical, spiny, with distinct collar stricture on the base, its apical opening central,

surrounded by a coronal of six to nine divergent denticulate spines. Length of the two joints = 5:6,

1 Amphiplecta = Shell at both poles open, with framework around;

1224 THE VOYAGE OF H.M.S. CHALLENGER.

breadth = 4:15. Thorax flatly conical/ armed with denticulate spines. Meshes of both joints
irregular, polygonal, twice to six times as broad as the bars. Basal mouth armed with longer,
divergent, denticulate spines,

Dimensions. — Cephalis 0;05 long, 0-04 broad ; thorax 0'06 long, 0-15 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

3. Amphiplecta callistoma, n. sp. (PL 59, fig. 2).

Cephalis flat, cap-shaped, spiny, with obliterated collar stricture on the base ; its apical opening
excentric, oblique, surrounded by a coronal of ten to twenty bristle-shaped spines. Length of the
two joints = 4:5, breadth = 7 : 25. Thorax flatly conical, armed with long bristle-shaped spines.
Meshes of both joints irregular, hexagonal, twice to six times as broad as the bars. Basal mouth
with a double irregular coronal of small square pores, and of bristle-shaped divergent spines.

Dimensions — Cephalis 0'04 long, 0'07 broad; thorax 0-05 long, 0"25 broad.

Habitat. — Central Pacific, Station 271, surface.

•Genus 548. Lychnocanium,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 54.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta), with three solid
/terminal feet on the peristome. No thoracic ribs. Cephalis with a horn.

The genus Lychnocanium, very rich in common living and fossil forms, comprises those
Sethopilida in which the thorax bears three simple terminal feet around the mouth, but
no lateral ribs in its wall. It has therefore been probably derived from Dictyophimus by
reduction and loss of these three lateral ribs. The mouth is commonly more or less
constricted. The three feet surrounding it are sometimes divergent, straight or curved,
at other times parallel and vertical, straight, or curved and convergent. The central
capsule exhibited in some living species three or four distinct lobes, filling up the upper
half of the thorax.

Subgenus 1. Lychnocanella, Haeckel.

Definition. — Feet divergent, straight or scarcely curved ; their terminal distance
greater than their basal distance.

1. Lychnocanium lanterna, n. sp. (PI. 61f fig. 7).

, Shell conical, rough, with slight collar stricture. Length of the two joints = 1 : 3, breadth =
1 : 3. -Cephalis with a stout pyramidal 'horn of the same length. Thorax pear-shaped, twice as

1 Lychnocanium = Lantern-basket ;

REPORT ON THE RADIOLARIA. 1225

broad as the constricted mouth, with regular, circular pores of the same breadth as the bars. Three
feet pyramidal, little divergent, straight, about as long as the cephalis.

Dimensions. — Cephalis O'OS long, 0'03 broad ; thorax 0'09 long, 0'08 broad.

Habitat. — Central Pacific, Stations 263 to 268, depth 2650 to 2900 fathoms.

2. Lychnocanium continuum, Ehrenberg.

Lychnocanium continuum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. vii.
fig. 11.

Shell smooth, with distinct collar stricture. Length of the two joints = 1:3, breadth = 1:3.
Cephalis subspherical with a conical horn of the same length. Thorax pear-shaped, twice as broad
as the constricted mouth, nearly hyaline, with a very small number of scattered minute pores.
Three feet pyramidal, little divergent, straight, about as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'06 long, 0'06 broad.

Habitat. — Fossil in Barbados.

3. Lychnocanium pyriforme, n. sp. (PL 61, fig. 11).

Shell pear-shaped, rough, with sharp collar stricture. Length of the two joints = 1:4, breadth
= 1:5. Cephalis hemispherical, with a conical horn of the same length. Thorax inflated, foul-
times as broad as the constricted tubular mouth, with regular, circular pores. Three feet pyramidal,
straight, divergent, about as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'12 long, 0'15 broad.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, many Stations ; also fossil in Barbados.

4. Lychnocanium favosum, n. sp. (PI. 61, fig. 6).

Shell campanulate, rough, with slight collar stricture. Length of the two joints =1:5, breadth
= 1:6. Cephalis hemispherical, with a rudimentary pyramidal horn of half the length. Thorax
subglobular, three times as broad as the constricted mouth, with regular, circular pores, and an
elevated hexagonal framework between them. Three feet cylindrical, slender, straight, divergent,
twice to three times as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0'025 broad ; thorax O'l long, 012 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

5. Lychnocanium nodosum, n. sp. (PI. 61, fig. 14).

Shell campanulate, nodose, with deep collar stricture. Length of the two joints = 1 : 3, breadth
= 1:4. Cephalis • subglobular, with a rudimentary conical horn of half the length. Thorax
nearly hemispherical, twice as broad as the flat mouth, with regular, circular pores, and a variable

(ZOOL. CHALL. EXP. — PART XL. — 1886.) J£r 154

1220 THE VOYAGE OF H.M.S. CHALLENGER.

number of scattered, conical, fenestrated protuberances. Three feet very large, prismatic, straight,
divergent, twice as long as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0-09 long, 012 broad.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

6. Lychnocanium carinatum, Ehrenberg.

Lychnocanium carinatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf.
viii. fig. 5.

Shell campanulate, with deep collar stricture. Length of the two joints =1:3, breadth = 1:3.
Cephalis subglobular, with a slender horn of the same length. Thorax conical, twice as broad as
the flat mouth, with fifteen- to twenty prominent, longitudinal, divergent ribs, alternating with the
same number of rows of pores. Three feet slender, prismatic, straight, divergent, twice as long as
the thorax.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax O06 long, 0'06 broad.

Habitat. — Fossil in Barbados.

7.. Lychnocanium ventricosum, Ehrenberg.

Lychnocanium ventricosum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf.
vii. fig. 12;

Shell pear-shaped, rough, with deep collar stricture. Length of the two joints = 1:3, breadth
= 1:4 Cephalis subglobular, with a stout conical horn twice the length. Thorax conical,
three times as broad as the constricted mouth, with irregular, roundish pores of different sizes.
Three feet stout, conical, divergent, half as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0-03 broad ; thorax 0'07 long, 0'09 broad.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms ; fossil in Barbados.

8. Lychnocanium tribulus, Ehrenberg.

Lychnocanium tribulus, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 80, Taf. vil
fig. 1.

Shell pear-shaped, nodose, with distinct collar stricture. Length of the two joints =•!.:. 4
breadth = 1:4 Cephalis subglobular, with a conical horn twice the length. Thorax ovate,
twice as broad as the constricted mouth, with irregular, roundish pores of different sizes. Three
stout feet strongly divergent, pyramidal, about as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; 0'08 long, 0'08 broad.

Habitat. — Fossil in Barbados.

Subgenus 2. Lychnocanissa, Haeckel.

Definition. — Feet divergent, more or less curved ; their terminal distance greater
than their basal distance.

REPORT ON THE RADIOLARIA. 1227

9. Lychnocanium fortipes, n. sp. (PI. 61, fig. 12).

Shell inflated, rough, with distinct collar stricture. Length of the two joints = 1 : 5,
breadth = 1 : 6. Cephalis small, hemispherical, with a pyramidal horn of half the length.
Thorax subglobular, truncate, twice as broad as the constricted mouth, with large, regular, circular
pores and very thin bars. Three feet very stout, prismatic, twice as long as the thorax, widely
divergent, curved with convexity outwards, club-shaped at the distal end, with denticulate edges.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax O'l long, 0'12 broad.

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

10. Lychnocanium falciferum, Ehrenberg.

Lychnocanium falciferum, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 7; Abhandl. d. k. Akad.

d. Wiss. Berlin, p. 78, Taf. viii. fig. 4.
Lithomelissa falcifera, Haeckel, 1862, Monogr. d. Radiol., p. 303.

Shell inflated, rough, with deep collar stricture. Length of the two joints = 1:3, 'breadth = 1:3.
Cephalis small, with a conical horn of half the length. Thorax subglobular, truncate, three times as
broad as the constricted mouth, with small, regular, circular pores. Three feet widely divergent,
twice as long as the thorax, curved like a crescent, with strong convexity outwards.

Dimensions. — Cephalis 0'02 long, 0'02 broad; thorax 0'06 long, 0'06 broad.

Habitat. — Fossil in Barbados.

11. Lychnocanium tuber osum, n. sp. (PI. 61, fig. 13).

Shell conical, tuberculate, with deep collar stricture. Length of the two joints = 1 : 3,
breadth = 1 : 4. Cephalis subglobular, with a conical horn of the same length. Thorax inflated,
twice as broad as the flat mouth, with small, irregular, roundish pores and scattered fenestrated
tubercles. Three feet very large, angular, three times as long as the thorax, curved like a crescent,
with strong convexity outwards.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'08 long, 0'12 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

12. Lychnocanium hirundo, Ehrenberg.

Lychnocanium hirundo, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 60, Taf. vii.

fig. 8.

Lithornithium hirundo, Ehrenberg, 1854, Mikrogeol., Taf. xix. fig. 53.
Lithocampe hirundo, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 65.

Shell conical, tuberculate, with slight collar stricture. Length of the two joints = 1 : 3,
breadth = 1:4. Cephalis hemispherical, with a conical horn of -half the length. Thorax cam-

1228 THE VOYAGE OF H.M.S. CHALLENGER.

panulate, twice as broad as the flat mouth, with longitudinal, divergent ribs, alternating with rows
of small circular pores. Three feet divergent, striated, gradually lessening from a broad base, twice
as long as the thorax, curved like a crescent, with convexity outwards.

Dimensions. — Cephalis 0'02 long, 003 broad ; thorax O06 long, 0'08 broad.

Habitat. — Fossil in Tertiary rocks of Barbados and the Mediterranean (Sicily, Greece).

13. Lychnocanium fenestratum, n. sp. (PI. 61, fig. 10).

Shell pear-shaped, rough, with slight collar stricture. Length of the two joints = 1:4, breadth
= 1:3. Cephalis subglobular, with a very large prismatic horn, which is about as long as the
shell, with three denticulate, prominent, wing-like crests, which are pierced by a series of pores.
Thorax ovate, three times as broad as the constricted, prominent mouth, with subregular, circular
pores. Three feet arising somewhat above the mouth, prismatic, with denticulate edges, about as long
as the thorax, divergent, curved, with convexity outwards.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'08 long, 0'08 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

14. Lychnocanium sigmopodium, n. sp. (PI. 61, fig. 15).

? Lychnocanium tetrapodium, Ehrenberg, 1875, Abhandl. d. fc. Akad. d. Wiss. Berlin, p. 80, Taf.
vii. fig. 3.

Shell campanulate, rough, with distinct collar stricture. Length of the two joints = 1:4,
breadth =1:3. Cephalis subspherical, with a slender, pyramidal horn twice the length. Thorax
inflated, conical, with regular, circular pores and a wide open mouth of nearly the same breadth.
Three feet widely divergent, twice as long as the thorax, angular, S-shaped, or curved with
convexity inwards. (Lychnocanium tetrapodium of Ehrenberg is perhaps a variety of this species ?).

Dimensions. — Cephalis 0'02 long, 0'03 broad; thorax 0'08 long, 0'09 broad.

Habitat. — Cosmopolitan; Mediterranean, Atlantic, Pacific, many stations at various depths ;
also fossil in Barbados and Sicily.

15. Lychnocanium trichopus, Ehrenberg.

Lychnocanium trichopus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. vii. fig. 5.

Shell conical, smooth, with deep collar stricture. Length of the two joints =1:3, breadth
= 1:3. Cephalis subspherical, with a rudimentary conical horn of half the length. Thorax cam-
panulate, with regular, circular pores and wide open mouth of nearly the same breadth. Three feet
divergent, very slender, four to five times as long as the thorax, not broader than one pore, S-shaped,
or curved with convexity inwards in the distal half.

Dimensions. — Cephalis 0'02 long, O'OS broad ; thorax 0'07 long, 0'09 broad.

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1229

Subgenus 3. Lychnocanoma, Haeckel.

Definition. — Feet parallel, vertical, straight, or little curved ; divergent in the basal
half, often convergent in the distal half ; their terminal distance about equal to the basal
distance.

16. Lychnocanium tripodium, Ehrenberg.

Lychnocanium tripodium, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. viis
fig. 2.

Shell ovate, smooth, with distinct collar stricture. Length of the two joints = 1:4, breadth =
1 : 4. Cephalis subglobular, with a slender conical horn twice the length. Thorax inflated,
twice as broad as the constricted mouth, with small, regular, circular pores. Three feet slender,
prismatic, twice to three times as long as the thorax, nearly straight and parallel, vertical.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'07 long, 0'07 broad.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms ; also fossil in-
Barbados.

17. Lychnocanium cypselus, Ehrenberg.

Lychnocanium cypselus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. vii.
fig. 10.

Shell slender, ovate, with slight collar stricture. Length of the two joints = 1:4, breadth =1:3.
Cephalis subspherical, with a conical horn of the same length. Thorax ovate, truncate, three times
as broad as the narrow, constricted mouth, with small, regular, circular pores. Three feet slender,
somewhat shorter than the thorax, little curved, with convexity outwards, nearly parallel, vertical.
(In the specimen figured by Ehrenberg, the third foot was broken off.)

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'08 long, 0'06 broad.

Habitat. — Fossil in Barbados.

18. Lychnocanium ovatum, n. sp.

Shell ovate, rough, without external collar stricture. Length of the two joints = 1 : 6, breadth
= 1:5. Cephalis conical, with a stout conical horn of the same length. Thorax ovate, four times
as broad as the narrow constricted mouth, with small, regular, circular pores, separated by hexagonal
frames of twice the breadth. Three feet cylindrical, half as long as the thorax, and three times .
as long as broad, straight, parallel, vertical.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax, 0'12 long, 01 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

1230 THE VOYAGE OF H.M.S. CHALLENGER,

19. Lychnocanium crassipes, Ehrenberg.

Lychnocanium crassipes, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. vii.
fig. 7.

Shell campanulate, rough, with deep collar stricture. Length of the two joints = 1 : 3, breadth
= 1:4. Cephalis subspherical, with a thin conical horn of the same length. Thorax semi-ovate,
three times as broad as the narrow constricted mouth, with fifteen to twenty divergent, denticulate
ribs, alternating with the same number of rows of small, regular, circular pores. Three feet very stout,
as long as the thorax, cylindrical, nearly straight and parallel, vertical, at the distal end clavate,
spinulate or a little forked.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0-06 long, 0*08 broad.

Habitat. — Fossil in Barbados,

20. Lychnocanium clavigerum, n. sp. (PI. 61, fig. 4).

Shell campanulate, sulcate, with sharp collar stricture. Length of the two joints = 1:4,
breadth = 1:5. Cephalis subglobular, with a spindle-shaped papillate horn twice the length.
Thorax nearly spherical, truncate at both poles, three times as broad as the narrow, constricted,
somewhat tubular mouth, with fifteen to twenty elevated meridional ribs, alternating with the same
number of rows of circular pores. Three feet slender, cylindrical, twice as long as the thorax, in
the basal half divergent, in the distal half convergent, club-shaped, with a thickened papillate end.

.Dimensions. — Cephalis 0'02 long, 0025 broad ; thorax 0'08 long, O01 broad.

'Habitat. — Indian Ocean, Madagascar, surface (Eabbe).

.2.1. Lychnocanium jzudicum, n. sp. (PL 61, fig. 2).

. Shell, campanulate, with deep collar strictura Length of the two joints = 1 : 3, breadth =1 : 3.
Cephalis hemispherical, hyaline (without pores), with a short and thick club-shaped, spinulate horn
of the same length. Thorax subglobular, truncate at both poles, twice as broad as the constricted
mouth*, with small, irregular, roundish pores. Three feet somewhat shorter than the thorax, curved
like a crescent, with convexity outwards ; their distal ends club-shaped, spinulate, convergent towards
the central axis.

'Dimensions. — Cephalis 0'02 long, 0'025 broad; thorax 0'06 long, O'OT broad.

.Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus. 549. ..Lychnodictyum,1 Haeckel, 1881, Prodromus, p. 432.

Definition. — S ethopilida (vel Dicyrtida triradiata aperta), with three latticed
terminal feet on the peristome, without thoracic ribs. Cephalis originally with a .horn
(sometimes lost).

1 Lychnodictyum = Lantern with network;

REPORT ON THE RADIOLARIA. 1231

The genus Lychnodictyum differs from the preceding Lychnocanium, only in the
fenestration of the three terminal feet, and bears therefore to it the same relation- that
the ancestral Tripocyrtis does to Dictyophimus.

1. Lychnodictyum challengeri, Haeckel.

Dictyopodium challengeri, Wyville Thomson, 1877, Atlantic, voL i. p. 234, fig. 52.
Dictyophimus (vel Tripocyrtis) challengeri, Haeckel, 1878, Protistenreich, p. 47, fig. 35.

Shell campanulate, smooth, with sharp collar stricture. Length of the two joints = 1 : 3j
breadth = 1:4. Cephalis subspherical, with a large, oblique, pyramidal horn thrice the length.
Thorax with three inflated bosoms between the three decurrent ribs, which are prolonged into three
vertical, parallel, pyramidal, in the upper half fenestrated feet, as long as the thorax. Pores regular,
circular. Mouth constricted, flat, half as broad as the thorax.

Dimensions. — Cephalis 0'03 diameter; thorax O08 long, 012 broad.

Habitat. — Tropical Atlantic, Station 338,. depth 1990 fathoms.

2. Lychnodictyum wyvillei, n. sp.

Shell pyramidal, smooth, with obliterated collar stricture. Length of the two joints = 1 : 3,
breadth = 1:5. Cephalis subspherical, with a large, straight, pyramidal horn of twice the length.
Thorax nearly tetrahedral, inflated, with three rounded, decurrent ribs, which are prolonged into three
widely divergent, angular, curved feet, about as long as the shell, with pyramidal fenestrated base.
Pores regular, circular. Mouth constricted, flat, half as broad as the thorax.

Dimensions. — Cephalis 0'025 diameter; thorax 0'08 long, 0-12 broad.

Habitat. — Central Pacific, Stations 266 to 274, depth 2350 to 2925 fathoms.

3. Lychnodictyum scaphopodium, n. sp. (PI. 56, fig. 4).

Cephalis hemispherical, large, without horn, with irregular, small, roundish pores. Thorax a
little larger, campanulate, with three broad, shovel-shaped, fenestrated, vertical feet, and larger,
irregular pores. In the figured specimen the third (posterior) foot was broken off. In another speci-
men the three feet were somewhat longer and not so broad.

Dimensions. — Cephalis 0'03 long, 0'05 broad ; thorax 0~05 long, 0'06 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms;

4. Lychnodictyum sethopodium, n. sp.

Cephalis hemispherical, large, with a rudimentary conical horn, and very scarce small pores.
Thorax twice as broad and long as the cephalis, campanulate, with irregular, roundish pores, and
three slender, pyramidal, divergent feet twice the length, which in the upper half are fenestrated,
in the lower half solid.

Dimensions. — Cephalis 0'025 long, 0'045 broad ; thorax 0'05 long, 0'09 broad.

Habited. — South Atlantic, Station 330, surface.

1232 THE VOYAGE OF H.M.S. CHALLENGES.

Subfamily 2. SETHOPERIDA, Haeckel, 1881, Prodromus, p. 433.

Definition. — T ripocyrtida with the basal mouth of the shell fenestrated (vel
Dicyrtida triradiata clausa).

Genus 550. Sethopera,1 Haeckel, 1881, Prodromus, p. 433.

Definition. — S ethoperida (vel Dicyrtida triradiata clausa), with three divergent
ribs enclosed in the latticed wall of the thorax. Cephalis with a horn.

The genus Sethopera is probably the oldest form of the Sethoperida, and may
therefore be regarded as the common ancestral form of this subfamily. The thorax
exhibits three radial ribs, which are completely enclosed in its wall. Sethopera may be
derived either from Dictyophimus or from another of the Sethopilida (Lamprodiscus,
Clathrocanium) by development of a basal lattice-plate closing the mouth). There
are often wide holes or open spaces between the three radial ribs.

1. Sethopera tricostata, n. sp. (PI. 97, fig. 11).

Cephalis subspherical, spinulate, with a pyramidal horn of the same length. Length of the two
joints = 5 : 8, breadth = 5 : 8. Thorax also nearly spherical; in the upper half with three stout,
prismatic, convex, divergent ribs, and three large ovate holes between them; in the lower half with
numerous small and irregular pores, spinulate.

Dimensions. — Cephalis 0'05 diameter ; thorax 0'08 diameter.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Sethopera Oceania, Haeckel.

Lithopera Oceania, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. iv. fig. 21.

Cephalis hemispherical, with a small bristle-shaped horn of half the length (broken oft' in
Ehrenberg's figure). Length of the two joints = 3:4, breadth = 3:4. Thorax nearly spherical ;
in the upper half with three divergent ribs, separated by some larger, irregular pores ; in the lower
half with numerous small, irregular, roundish pores.

Dimensions. — Cephalis 0-03 long, 0'03 broad ; thorax 0'04 long, 0'04 broad.

Habitat. — North Atlantic, Station 354, surface ; Canary Islands and Azores.

3. Sethopera pyrum, Haeckel.

1 Lithopera pyrum, Ehrenberg, 1872, Abhandl. d. k. Akad.' d. Wiss. Berlin, p. 297.

Cephalis hemispherical, with a small conical horn of half the length. Length of the two
joints = 3 : 10, breadth = 3 : 1. Thorax pear-shaped, with rather large, regular, quincuncial pores ;

1 Sethopera = Sieve-pouch ;

REPORT ON THE RADIOLARIA. 1233

its upper half with three divergent ribs in the wall, half as broad as the subspherical lower half.
(The three ribs probably were overlooked by Ehrenberg.)

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax 01 long, O'OT broad.

Habitat. — North Pacific, Station 256, surface ; Californian Sea, 2600 fathoms, Ehrenberg.

4. Sethopera lagena, Haeckel.

Lithopera lagena, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii. fig. 4.

Cephalis pear-shaped, with a small conical horn of half the length. Length of the two
joints = 3:8, breadth = 3:6. Thorax smooth, pear-shaped, with irregular roundish pores ; in the
wall of its upper third three divergent thin ribs (sometimes wanting) ; the lower half inflated.
(Compare Sethocapsa lagena.)

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax 0'08 long, 0'06 broad.

Habitat. — Fossil in Barbados.

Genus 551. Lithopera,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — S ethoperida (vel Dicyrtida triradiata clausa), with three divergent
ribs enclosed in the cavity of the thorax. Cephalis with a horn.

The genus Lithopera is, like the preceding Sethopera, one of the most simple and
oldest forms of the Sethoperida, and exhibits three divergent thoracic ribs, which are
prolonged neither into lateral wings nor into basal feet. But whilst in Sethopera the
three ribs are enclosed in the lattice-work of the shell-wall, in Lithopera they lie freely
in its cavity, and are overgrown by the enveloping shell-wall, being inserted on its inner-
face with their distal ends. Lithopera may be derived directly from Lithomelissa, by
development of lattice-work closing the shell-mouth. Therefore the lower part of the
cephalis is hidden in the uppermost part of the thorax ; only its upper part is free.

1. Lithopera bacca, Ehrenberg.

Lithopera bacca, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. viii. fig. 1.

Cephalis spherical, with small, irregular pores and a bristle-shaped spine of half the length ; its
lower half hidden in the thorax. Length of the two joints = 1:6, breadth = 1:5. Thorax
ellipsoidal, smooth, with regular, hexagonal, small pores, and very thin, thread-like bars. From the
deep collar stricture there arise three internal, divergent bars, which are inserted at the uppermost
third of the thorax.

Dimensions. — Cephalis 0'02 diameter ; thorax 0'12 long, O'l broad.

Habitat. — Tropical Pacific, Stations 200, 224, 266, 271, &c., surface.

1 Lithopera = Stone-pouch ; A/0oj, aijja.

(ZOOL. CIIALL. EXP. — PART XL. — 1886.) Rr J55

1234 THE VOYAGE OF H.M.S. CHALLENGER.

2. Lithopera bursella, Ehrenberg.

Lithopera bursella, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. x. fig. 4.

Shell of about the same form and structure as in the nearly allied preceding species, but smaller,
of more slender form, with smaller pores and thinner bars. Length of the two joints = 1 : 5,
breadth = 1 : 3. In the specimen observed by me the three internal, divergent bars of the ellipsoidal
thorax (not seen by Ehrenberg) were as distinct as in the similar preceding and following species.

Dimensions. — Cephalis O02 diameter ; thorax 01 long, 0'06 broad.

Habitat. — Indian Ocean, Zanzibar (Pullen), Madagascar (Eabbe), surface.

3. Lithopera ananassa, n. sp. (PI. 57, fig. 3).

Shell of about the same form and structure as in the two preceding species, but larger and
more robust, and differing in the spiny surface. Length of the two joints =1:5, breadth = 1:4
Here also the lower half of the spherical cephalis is submerged in the ellipsoidal thorax, and from
the collar stricture arise three strong, internal, divergent beams. The bars of the hexagonal pores
•are much thicker than in the two preceding species.

Dimensions. — Cephalis 0'03 diameter; thorax 016 long, 012 broad.

Habitat. — Tropical Atlantic, Stations 347 to 352, surface.

4. Lithopera globosa, n. sp.

Cephalis spherical, very small, with two divergent conical horns of half the length ; its lower
half hidden in the thorax. Length of the two joints = 1:5, breadth =1:5. Thorax spherical, with
regular, circular, hexagonally-framed pores. From the collar stricture arise three radial internal
beams, horizontally diverging, and inserted at the inside of the thorax.

Dimensions. — Cephalis 0-03 diameter ; thorax 015 diameter.

Habitat. — Central Pacific, Stations 271, depth 2425 fathoms.

5. Lithopera gutta, Ehrenberg.

Lithopera gutta, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wis& Berlin, p. 297, Taf. viii. fig. 2,

Shell pear-shaped, with sharp collar stricture. Length of the two joints = 1 : 4, breadth =1 : 3,
Cephalis spherical, with a conical horn of the same length ; its lower half hidden in the uppermost
part of the ovate thorax, and connected with its wall by three internal, cortinar beams. Pores of the
thorax very irregular in form and size, partly lobed.

Dimensions. — Cephalis 0'02 diameter; thorax 0'08 long, 0'06 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms ; Philippine Sea (depth
3300 fathoms), Ehrenberg.

REPORT ON THE RADIOLARIA. 1235

Genus 552. Micromelissa,1 Haeckel, 1881, Prodromns, p. 433.

Definition. — S ethoperida (vel Dicyrtida triradiata elausa), with three divergent,
solid, lateral wings. Cephalis with a horn.

The genus Micromelissa differs from the two preceding genera in the free pro-
minence of the three cortinar ribs, forming three solid lateral wings. Beyond these
the thorax walls are convergent, and the basal mouth closed by a lattice-plate.
Therefore Micromelissa may have arisen from Lithomelissa simply by development of
this basal mouth -plate.

1. Micromelissa bombus n. sp. (PI. 57, fig. 14).

Shell smooth, with sharp collar stricture. Length of the two joints =1:4, breadth = 1:5.
Cephalis spherical, with an oblique conical horn of the same length. Thorax subspherical, in the
upper half with three conical, downwardly diverging wings, about as long as its radius. Pores very
small and scarce.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'09 long, 0"! broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Micromelissa vespa, n. sp.

Shell smooth, with deep collar stricture. Length of the two joists = 2 : 5, breadth = 2 : 3.
Cephalis spherical, with an oblique pyramidal horn twice the length. Thorax inversely ovate,
in the upper half with three, pyramidal wings, which are equal to its breadth, little curved and
diverging downwards. Pores very small and scarce.

Dimensions. — Cephalis 0'04 diameter ; thorax O'l long, 006 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Micromelissa apis, n. sp.

Shell rough, with deep collar stricture. Length of the two joints = 2:3, breadth = 2:4.
Cephalis subspherical, with a straight conical horn of half the length, and subregular, circular, double-
contoured pores, of the same breadth as the bars. Thorax little larger, subspherical, with irregular,
roundish pores, twice to four times as broad as the bars. From its lower half arise three short
conical wings, curved downwards, and half as long as the cephalis.

Dimensions. — Cephalis 0'04 long, 0'04 broad ; thorax 0'06 long, 0'08 broad.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

1 Micromelissa = Small bee ; fttx,i>6s, pieman..

1236 THE VOYAGE OF H.M,S. CHALLENGER.

4. Micromelissa microptera, Haeckel.

Lithometinsa microptera, Elirenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 2 ; Abhandl. d. k. Akad.

d. Wiss. Berlin, 1875, p. 78, Taf. iii. fig. 13.
Lithomelissa microptera, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 539, Taf. xxxiii.

fig. 26.

Shell smooth, with distinct collar stricture. Length of the two joints = 4 : 6, breadth = 3 : 5.
Cephalis ovate, with a straight sword-shaped horn of the same length and very small pores, some
larger ones above the stricture. Thorax little larger, ovate, nearly hyaline, with very few and small
scattered pores. From its uppermost part arise three short conical wings, scarcely half as long as the
cephalic horn, little curved and divergent downwards.

Dimensions. — Cephalis 0'04 long, O03 broad ; thorax 0'06 long, 005 broad.

Habitat. — Fossil in Barbados.

5. Micromelissa ventricosa-, HaeckeL

Lithomelissa ventricosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii.
fig. 11.

Shell rough, with slight collar stricture. Length of the two joints —1:7, breadth = 1:5.
Cephalis small, hemispherical, with a small conical horn of half the length, Thorax ovate, very
large, papillate, with irregular, roundish pores. From its basal part arise three short and stout
conical wings at great distances, shorter than the cephalis. (A transition-form to Sdhocapsa.)

Dimensions. — Cephalis O02 long, 0'022 broad ; thorax 014 long, O'll broad.

Habitat. — Fossil in Barbados.

Genus 553. Peromelissa,1 Haeckel, 1881, Prodromus, p. 433.

Definition. — Sethoperida (vel Dicyrtida triradiata clausa) with three divergent
solid lateral wings. Cephalis without horn.

The genus Peromelissa differs from the preceding ancestral form, Micromelissa,
only in the absence of the cephalic horn, which is lost by reduction.

1. Peromelissa phalacra, n. sp. (PI. 57, fig. 11).

Shell smooth, with two joints of nearly equal size and similar ovate form. Cephalis in the
upper half hyaline, without pores ; in the lower half with four remote, transverse rows of irregular,
roundish pores, decreasing in size towards the hemispherical summit. Thorax with twelve- transverse

1 Peromelusa=:Ponch-\)ee ;

REPORT ON THE RADIOLARIA. 1237

rows of pores, the upper six rows three to four times as large as the lower six rows. From its upper
half diverge almost horizontally three angular club-shaped wings, half as long as the shell

Dimensions. — Cephalis O05 long, 0'06 broad ; thorax 0'06 long, O05 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Peromelissa psilocrana, n. sp.

Shell smooth, very similar to the preceding species in size and form, but differing from it in the
disposition of the irregular, roundish pores, which are irregularly scattered, and in the form of the
three wings, which are slender, pyramidal, diverging downwards, and about as long as the entire shell.

Dimensions. — Cephalis 0'07 long, 0'06 broad ; thorax 0'07 long, 0'06 broad

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Peromelissa capita, Haeckel.

Lithomelissa capita, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii. fig. 14.

Shell rough, with two joints of nearly equal size and similar ovate form. Pores irregular;
roundish, everywhere scattered. From the upper half of the thorax arise three short conical wings,
which are little curved and diverge downwards (scarcely half as long as the breadth of the shell).

Dimensions. — Cephalis 0'07 long, 0'06 broad ; thorax 0'07 long, 0'06 broad.

Habitat. — Fossil in Barbados.

4. Peromelissa calva, n. sp. (PI. 57, fig. 12).

Shell rough, with two ovate joints of somewhat different sizes. Pores irregular, roundish, every-
where scattered. Thorax little larger than the oephalis ; from its upper half arise three short
conical wings, diverging downwardly or nearly horizontally.

Dimensions. — Cephalis 0'06 long, 0'04 broad ; thorax 0'7 long, 0'05 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 554. Sethomelissa,1 Haeckel, 1881, Prodromus, p. 431.

Definition. — S ethoperida (vel Dicyrtida triradiata clausa) with three divergent
latticed lateral wings. Cephalis with a horn (or a bunch of horns)..

The genus Sethomelissa differs from the nearly allied Micromelissa in the fenestra-
tion of the three lateral wings, and may be derived either from this genus by develop-
ment of lattice-work connecting the three wings with the shell, or perhaps from
Clathrocanium by closing the mouth.

1 Sethomelissa = Sieve-bee ; aii$a, fahiatct.

1238 THE VOYAGE OF H.M.S. CHALLENGER.

1. Sethomelissa hymenoptera, n. sp.

Cephalis subspherical, thorny, with a bunch of three divergent, larger apical spines. Thorax
;pear-shaped, with three broad, triangular, latticed wings, the superior edge of which is a horizontal
straight, and stout spine, nearly as long as the thorax. Pores irregular, roundish.

Dimensions. — Cephalis O03 diameter; thorax Oil long, 0'08 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

.
Genus 555. Tetrahedrina,1 Haeckel, 1881, Prodromus, p. 433.

Definition. — Sethoperida (vel Dicyrtida tr-iradiata clausa) with a three -sided
pyramidal thorax, the three edges of which are prolonged into three divergent, solid,
terminal feet. Cephalis with a horn.

The genus Tetrahedrina, and the two following nearly allied genera, are distin-
guished by the possession of three free, divergent, terminal feet, projecting over the
latticed mouth of the thorax. Tetrahedrina may be derived directly from Dictyo-
phimus, by development of a horizontal latticed mouth -plate from the middle part of the
feet, the lower part of which remains free. This genus, not noticed by Ehrenberg, is-
similar to his Lithochytris, and common in the Barbados deposits.

1. Tetrahedrina pyramidalis, n. sp.

Shell three-aided pyramidal, smooth, with slight collar stricture. Length of the two joints = 1 : 4,.
breadth = 1:4 Gephalis hemispherical, with small, sparsely disposed pores, and a pyramidal horn of
the same length. Thorax with subregular, circular pores and three sharp edges, prolonged into three
divergent pyramidal feet of the same length.

Dimensions. — Cephalis 0'03 diameter ; thorax 012 long, 012 broad.

Habitat. — Fossil in Barbados.

2. Tetrahedrina pyriformis, n. sp:

Shell pear-shaped, rough, with distinct collar stricture. Length of the two joints = 2:6,
breadth = 2:5. Cephalis subspherical, with a conical horn of the same length. Thorax with sub-
regular, circular pores, ovate, at the broad base with three pyramidal, widely divergent feet of the
same length. (Similar to Lyehnocanium tribulus, Ehreuberg, 1875, loc. tit., pi. vii. fig. 1, but with
the mouth closed by a lattice-plate.)

Dimensions. — Cephalis 0'04 diameter ; thorax 012 long, 01 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

1 Tetrahedrina =:Small tetrahedron ;

REPORT ON THE RABIOLARIA. 1239

3. Tetrahedrina quadricornis, Haeckel.

Lithochytris triangula, Bury, 1862, Polycystins of Barbados, pi. xix. figs. 4, 5, 6.

Shell pear-shaped, papillate, with slight collar stricture. Length of the two joints = 1:5,.
breadth =1:5. Cephalis subspherical, with a stout conical horn twice the length. Thorax with
irregular, roundish, lobulated pores, with three conical, stout, divergent feet at the base, of the same/
size and form as the cephalic horn.

Dimensions. — Cephalis 0'02 diameter ; thorax 01 long, O'l broad.

Habitat. — Fossil in Barbados.

Genus 556. Sethochytris,1 Haeekel, 1881, Prodromus, p. 433.

Definition. — S ethoperida (vel Dicyrtida triradiata clausa) with three terminal
latticed feet or hollow, fenestrated, divergent, basal apophyses of the thorax. Cephalis
with a horn.

The genus Sethochytris differs from the preceding Tetrahedrina in the fenestration of
the three basal feet, which form direct protrusions or evaginations of the three basal
Corners of the pyramidal shell. It may be derived from Sethopera by centrifugal growth
of the basal corners.

1. Sethochytris triconiscus, n. sp. (PI. 57, fig. 13).

Shell rough, with deep collar stricture. Length of the two joints = 1:8, breadth = 1:3.
Cephalis spherical, with an oblique pyramidal horn of the same length. Thorax campanulate,
conical ; its three basal corners prolonged into three divergent, slender, hollow, fenestrated cones,
twice as long as the thorax, and ending in a stout pyramidal spine.

Diinensions. — Cephalis 0'04 diameter, thorax 012 diameter, length of the feet 0'2.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Sethochytris Ijarbadensis, Haeckel.

Lithochytris barbadensis, Ehreriberg, 1875, Abhandl. d. t. Afead. d. Wiss. Berlin, p. 160,
Taf. v. fig. 2.

Shell smooth, with slight collar stricture. Length of the two joints = 1:6, breadth = 1:4.
Cephalis ovate, with a conical horn of half the length. Thorax conical ; its base prolonged into
three divergent, hollow, fenestrated cones, half as long as the thorax. Pores small, subregular.
circular.

Dimensions. — Cephalis 0'025 diameter, thorax 01 diameter, length of the feet 0'05.

Habitat — Fossil in Barbados.

1 Sethochytris = Sieve-pot ; a>iiu,

1240 THE VOYAGE OF H.M.S. CHALLENGER.

3. Sethochytris pyramis, n. sp.

Shell smooth, with slight collar stricture. Length of the two joints = 1:8, breadth = 1:5.
Cephalis ovate, with a conical horn of half the length. Thorax pyramidal, with three sharp edges ;
its base prolonged into three pyramidal, divergent, hollow, fenestrated feet, nearly as long as the
thorax. Pores regular, circular, doable-contoured.

Dimensions.— Cephalis 0-04 diameter ; thorax 0'2 diameter, length of the feet 015.

HaUtat. — Central Pacific, Station 265, depth 2900 fathoms ; also fossil in Barbados.

4. Sethochytris triangula, Haeckel.

Lithochytris triangula, Bury, 1862, Polycystins of Barbados, pi. xix. fig. 7.

Shell rough, with obliterated collar stricture (but distinct internal collar septum). Length of
the two joints = 1 : 6, breadth = 1:3. Cephalis subspherical, with a stout conical horn of the same
length. Thorax pear-shaped, inflated ; its base prolonged into three divergent, hollow, fenestrated
cones, about as long as the thorax. Pores regular, circular.

Dimensions. — Cephalis 0'03 diameter; thorax 0'09 diameter, length of the feet 01.

Habitat. — Fossil in Barbados.

Genus 557. Clathrolychnus,1 Haeckel, 1881, Prodromus, p. 431.

Definition. — S ethoperida (vel Dicyrtida triradiata clausa), with three vertical,
lateral latticed wings stretched between the apical horn and the three terminal feet.
The external lattice-work connecting the wings and closing the mouth forms an arachnoidal
mantle around the shell.

The genus Clathrolychnus may be. derived directly from Clathrocorys, by develop-
ment of an external arachnoidal mantle connecting the three wings and the three feet,
and enveloping the whole shell, closing at the same time the basal mouth of the thorax
by a fenestrated plate.

1. Clathrolychnus araneosus, n. sp. (PL 64, fig. 5).

Cephalis subspherical, with irregular, polygonal pores and a large pyramidal horn of twice the
length. Length of the two joints = 4 : 9, breadth ='5 : 12. Thorax with three large triangular
holes (twice as broad as the cephalis) between the three pyramidal, divergent feet, which at the
distal end are connected by a narrow band of network, composed of two or three rows of polygonal
pores. The entire pyramidal shell is enveloped by a very delicate web of irregular, polygonal

1 Clathrolychnus = Fenestrated lantern ;

REPORT ON THE RADIOLARIA. 1241

meshes, closing also the basal mouth. (In fig. 5 the greater part of the web is taken off to
demonstrate the large holes of the thorax). Only two feet are visible.

Dimensions. — Cephalis 0'04 long, 0'05 broad ; thorax 0'09 long, 0'12 broad.

Habitat. — Central Pacific, Station 274, surface.

2. Clathrolychnus periplectus, n. sp. (PL 64, fig. 6).

Cephalis subspherical, with subregular, circular pores and a pyramidal horn of the same length.
Length of the two joints =1:2, breadth =1:3. Thorax with three large elliptical holes between
the three pyramidal, divergent feet, which are connected at the distal end by a broad band of net-
work, composed of five to ten rows of polygonal pores. The entire pyramidal shell is enveloped by
a very delicate web, which on the sides is composed of subregular, square meshes, and on the closed
mouth of polygonal meshes. (In fig. 6 only a part of the web is represented.)

Dimensions. — 0'04 long, 0'05 broad ; thorax 0'08 long, O14 broad.

Habitat. — Central Pacific, Station 271, surface.

Family LXIII. ANTHOCYKTIDA, n. fam.

Sethophormida et Setlwphxnida, Haeckel, 1881, Prodromus, p. 432, 433.

Definition. — D icyrtida multiradiata. (Cyrtoidea with a two-jointed
shell, divided by a transverse constriction into cephalis and thorax, and bearing
numerous — four to nine or more — radial apophyses.)

The family Anthocyrtida, composed of the Sethophormida and Sethophaenida of
my Prodromus, comprises those Cy rto id e a in which the shell is two -jointed and
bears numerous radial apophyses. The two subfamilies differ in the shape of the
mouth, which in the Sethophormida is a simple, wide opening ; in the Sethophsenida
closed by a lattice-plate.

Numerous fossil and living forms of Anthocyrtida were described formerly by
Ehrenberg in his genera Carpocanium and Anthocyrtis. These, however, represent
only a small part of the whole family, which exhibits a great variety in the composition
of the lattice-work and in the number of radial beams. The number of species here
described amounts to one hundred and forty, and these are disposed in fourteen genera
(twelve Sethophormida and two Sethophasnida).

The Sethophormida may be again divided into two different groups or tribes, the
Sethamphorida and Carpocanida ; in the former the thorax bears numerous radial
ribs, enclosed in its wall ; in the latter these ribs have disappeared, and only a corona
of terminal feet is developed around the mouth. The shell of the former is usually
pyramidal, with a widely open mouth ; of the latter ovate, with a constricted mouth.
The mouth of the thorax becomes perfectly closed in the SethophaBnida.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 156

1242

THE VOYAGE OF H.M.S. CHALLENGER.

The majority of the Anthocyrtida may be derived from the Polyspyrida (Petalo-
spyris, &c.) by reduction of the cephalis and loss of the sagittal ring, as was suggested by
Biitschli (1882, loc. cit.). But another part may also have arisen from the Tripocyrtida,
by interpolation of secondary radial apophyses between the three primary perradial
apophyses. The cephalis in this family is developed in all possible degrees, from one of
a considerable size to one very much reduced. If it becomes perfectly lost, the Cyrto-
ealpida arise.

Synopsis of the Gene™ of Anthocyrtida.

L Subfamily

Sethophormida.
Terminal mouth of the
thorax a simple wide
opening.

II. Subfamily

Sethophsenida.
Terminal mouth closed
by a lattice-plate.

f Shell flat, campanulate or
nearly discoidal (cephalis
without horn),

Kadial ribs smooth (rarely
thorny) enclosed in the
wall of the thorax (cepha- •
lis commonly small, with-
out horns).

Shell ovate, with constricted
mouth (without horn),

Meshes of
the network
simple,

Shell

slender

pyramidal,

with straight

ribs.

Radial ribs thorny (rarely
smooth) prolonged into
free terminal feet (cepha- -I.
lis commonly large, with |

Meshes fenes-
trated by
secondary lat-
ticework,

Meshes closed
by spongy
framework, .

Shell not enveloped by arach-
noidal network,

one or more horns).

Shell enveloped by arachnoidal
[ network, .

"Feet

Six feet,

Cephalis

terminal,

wityimTf

Nine feet,

No ribs in

well-

W 1 1 1 M H 1 1 *

the thorax.
Peristome

developed, -
with an

separate
peristome.

Twelve or more
feet,

with free

apical horn.

terminal

Feet subterminal, outside the

feet.

constricted peristome,

Cephalis rudimentary, hidden in the upper

part of the thorax, without horn, .

Thorax with lateral apophyses (four to six or more wings), .
Thorax with terminal apophyses (four to six or more feet), .

558. Sethophormis,

559. Sefhamphora.

560. Setliopyramis.

561. Pledopyramis.

562. Spongopyramis.

563. Accunthocarys.

564. Arachnocorys.

565. Anthocyrtonm.

566. AntJwcyrtis.

567. Antboajriium.

568. Anthocyrtidium.

569. Carpocanium.

570. SeihopluKiia.

571. Clistophcena.

REPORT ON THE RADIOLARIA. 1243

Subfamily 1. SETHOPHORMIDA, Haeckel, 1881, Prodromus, p. 432.

Definition. — A nthocyrtida with the basal mouth of the shell open (vel Dicyrtida
multiradiata aperta).

Genus 558. Sethophormis, Haeckel,1 1881, Prodromus, p. 432.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) with numerous
radial ribs in the wall of the flat and broad, campanulate or nearly discoidal thorax.
Cephalis also flat and broad, cap-shaped, without horn.

The genus Sethophormis comprises a great number of widely distributed and large
Dicyrtida, all agreeing in the flat cap-shaped or nearly discoidal form of the thorax, which
has constantly a very delicate network, and is pierced by numerous radial beams. Four
of these are commonly primary and direct prolongations of the four cortinar rods in the
collar septum, whilst the others are secondary or interpolated ribs. Sethophormis may be
derived either from the triradial Lamprodiscus by multiplication of the ribs (or interpo-
lation of secondary ribs between the three primary), or from Halicalyptra by develop-
ment of transverse rods connecting its terminal feet, and forming a ribbed thorax.
Corresponding to the number of the ribs, we may distinguish as subgenera (separate
genera in my Prodromus, 1881, p. 432) Tetraphormis with four, Pen taphormis with five,
Hexaphormis with six, Octophormis with eight, Enneaphormis with nine, and Astro-
phormis with ten to twenty or more ribs. The cephalis bears no horn, and is usually
large, flat, cap-shaped or hemispherical.

Subgenus 1. Tetraphormis, Haeckel, 1881, Prodromus, p. 432.

Definition. — Thorax with four radial ribs, opposite in pairs in two meridional planes,
perpendicular to one another. Collar septum with four large pores.

1. Sethophormis cruciata, n. sp.

Cephalis very large, hemispherical, with irregular, delicate network of small square meshes.
Thorax flatly campanulate, with delicate, regular network of small hexagonal meshes. All bars
very thin, thread-like. Four stout radial thoracic ribs, crossed in pairs, lie in two meridional planes,
perpendicular to one another. Very similar to Sethophormis aurelia (PI. 55, figs. 3, 4), but not so
flat, and with only four thoracic ribs. Peristome or margin of the thoracic mouth smooth, circular.

Dimensions. — Cephalis 0'04 long, 0'08 broad ; thorax 0'12 long, 0-36 broad.

Habitat. — Central Pacific, Station 271, surface.

1 Sethophormis = Sieve-basket ; atiS

1244 THE VOYAGE OF H.M.S. CHALLENGER.

2. Sethophormis medusa, n. sp.

Cephalis very large, flat, cap-shaped, with irregular, delicate network of polygonal meshes.
Thorax flat, campanulate, nearly hemispherical, with delicate, irregular network of small polygonal
meshes. All bars very thin, thread-like. Four stout radial thoracic ribs, as in the preceding
species. Peristome denticulate.

Dimensions. — Cephalis 0'03 long, 0'09 broad; thorax 015 long, 0-25 broad.

Habitat. — North Pacific, Station 244, surface.

Subgenus 2. Pentaphormis, Haeckel, 1881, Prodromus, p. 432.

Definition. — Thorax with five radial ribs, one of the three primary ribs (-the odd
occipital rib) being simple, the two others (the paired lateral ribs) forked.

3. Sethophormis pentalactis, n. sp. (PI. 56, fig. 5).

Cephalis large, flat, hemispherical, with subregular, hexagonal pores. Thorax flat, campanulate,
nearly hemispherical ; also with subregular, hexagonal pores, and with five stout ribs. The three
primary ribs of the thorax are complete, and reach the peristome ; the two secondary ribs (as basal
branches of the two lateral ribs) are incomplete and absent in the distal half of the thorax. Peri-
stome denticulate, with an elegant marginal corona of small square pores and short conical spines.

Dimensions. — Cephalis 0'03 long, 0'06 broad ; thorax 01 long, 0'2 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

4. Sethophormis asteriscus, n. sp.

Cephalis large, flat, cap-shaped, with irregular polygonal pores. Thorax flat, campanulate, with
subregular, hexagonal pores, and five stout ribs. The marginal distance between the two anterior
(lateral) ribs is twice as great as the distance between every two other ribs (the postero-lateral ribs
being basal branches of the antero-lateral ribs). Peristome with a double corona of short, conical,
spines.

Dimensions. — Cephalis 0-02 long, 0'04 broad; thorax 0'06 long, 017 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Sethophormis astrodiscus, n. sp.

Cephalis small, flatly vaulted, cap-shaped, with irregular, polygonal pores. Thorax very flatly
vaulted, nearly discoidal, with subregular, hexagonal pores, and five stout ribs. The marginal dis-
tance between all five ribs is nearly equal. Peristome denticulate, with an elegant corona of small
square pores and short conical thorns.

Dimensions.— Cephalis O'OIS long, 0'035 broad ; thorax 0'05 long, 0'2 broad.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

REPORT ON THE RADIOLARIA. 1245

Subgenus 3. Hexaphormis, Haeckel, 1881, Prodromus, p. 432.

Definition. — Thorax with six radial ribs (three primary perradial and three second-
ary interradial beams).

6. Setho2)hormis hexalactis, n. sp. (PL 56, fig. 6).

Cephalis large, hemispherical, with irregular, polygonal pores. Thorax flatly campanulate, with1
subregular, hexagonal pores, and six stout radial ribs ; the lateral connected in pairs. (Fig. 6
exhibits the central part of the shell, seen from below.) In the subcircular collar septum the two
anterior (jugular) meshes are much smaller than the two posterior (cardinal) meshes. The odd
anterior (sternal) rib is opposite to the posterior (caudal) rib. The two paired ribs of each side
(antero-lateral or pectoral and postero-lateral or ventral ribs) diverge from one common point. In
the specimen figured the left half of the thorax exhibited the two regular ribs, and the right half
three, a posterior accessory branch being developed (transition to Octophormis). This specimen- might
indeed be called ffeptapkormis heptalactis.

Dimensions. — Cephalis 0'02 long, 0'05 broad; thorax 0'08 long, Q-22 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

7 . Sethophormis hexagonalis, u. sp.

Cephalis small, Hat, cap-shaped, with small, regular, hexagonal pores. Thorax flatly: conical^
nearly discoidal, with larger pores of the same form, and six stout, straight, prominent ribs.
These arise at equal distances from the six corners of the hexagonal base of the collar septum.
Peristome hexagonal, with a corona of short spines.

Dimensions. — Cephalis 0'015 long, 0'04 broad; thorax 0'06 long, 0'24 broad.

Habitat. — North Atlantic, Station 354, surface.

Subgenus 4. Octophormis, Haeckel.

Definition. — Thorax with eight radial ribs, four secondary interradial beams
being interpolated between the four primary perradial beams of Tetraphormis.

8. Sethophormis octalactis, n. sp.

Cephalis large, hemispherical, with irregular, polygonal pores. Thorax flatly campanulate, with
regular, hexagonal pores, and eight stout, regularly-disposed, radial ribs reaching the margin at
equal distances. Foxir of these correspond to the four primary ribs of Tetraphormis cruciata, and
exhibit at their base a larger pair of basal pores, surrounded by a semicircular ring (PL 70, fig. 5) ;
the other four are secondary, interpolated. Peristome circular, simple.

Dimensions.— Cephalis 0'03 long, 0'06 broad ; thorax 01 long, 0'22 broad.

Habitat. — Indian Ocean, Madagascar (Rabbe), surface.

1246 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 5. Enneaphormis, Haeckel, 1881, Prodromus, p. 432.

Definition. — Thorax with nine radial ribs, three of which are the primary beams,
the other six being secondary and interpolated.

9. Sethophormis rotuta,, n. sp. (PI. 57, fig. 9).

Enneatphormis rotula, Haeckel, 1881, Prodromus et Atlae, pi. Ivii. fig. 9.

Cephalis very large, flat, cap-shaped,, trilobed, with irregular, polygonal network. Horizontal
collar-ring stout, hexagonal, with three larger and three alternate smaller sides of half the length.
From the middle of the three larger sides arise three horizontal, centripetal, radial beams, which are
united in the centre of the collar-septum — the three primary cortinar beams. These are prolonged
outside into three centrifugal primary ribs of the thorax. Prom the six corners of the collar-ring
arise six other secondary, thoracic ribs, equal in size and similar in form to the three primary.
Each of these nine equal, straight ribs of the thorax is thickened towards the distal end, and bears
at equal distances five pairs of opposite (tangential) lateral branches. The opposite branches of the
neighbouring spines become united, and lie nearly horizontally in one plane, so that the Hat, dis-
coidal thorax is like a nine-angled wheel with nine equally distant spokes and five concentric, nine-
angled rings.

Dimensions. — Cephalis 012 diameter, thorax 0'36 diameter.

Habitat. — Central Pacific, Stations 270 to 274, depth 235.0 to 2925 fathoms.

10., Sethophormis triloba, n. sp.

Cephalis large, hemispherical, distinctly trilobed, with dense, irregular, polygonal network. From
the centre of its top diverge three stout arches or semilunar rods, which are curved downwards, and
unite with the three horizontal, radial beams of the collar-septum inside the collar-ring. These three
parietal arches of the cephalis are much stronger than in the similar preceding species (PL 57, fig. 9),
and between them are placed three vaulted bosoms of the cephalis. The collar-ring and the thorax
are of the same form as in the preceding, but possess only four concentric, nine-angled rings.

Dimensions.— Cephalis 0'05 long, 0'08 broad ; thorax 0'24 diameter.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

11. Sethophormis enncastrum, n. sp.

Cephalis very large, flat, cap-shaped, with hexagonal base, trilobed, of similar form and struc-
ture to the two preceding species. The flat, discoidal thorax has also the same form, with nine stout
ribs and five concentric, ,nine-angled rings ; its forty-five large meshes, however, are not so simple

REPORT ON THE RADIOLARIA. 1247

as these (PI. 57, fig. 9), but are subdivided into irregular, smaller meshes by interpolated radial
beams connecting the concentric rings.

Dimensions. — Cephalis O'l diameter, thorax 0'3 diameter.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

12. Sethophormis arachnium, n. sp.

Cephalis very large, flat, cap-shaped, trilobed, with hexagonal base, of the same structure as in
the three preceding species. The flat discoidal thorax is also similar, and has the same structure as
in the preceding species (PI. 57, fig. 9) ; but the number of concentric, nine-angled rings is raised
from five to eight, and in its outer part nine secondary radial beams are interpolated between the
nine primaries, so that the peristome has not nine but eighteen corners.

Dimensions. — Cephalis 0'08 diameter, thorax 0'4 diameter.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

13. Sethophormis enneactis, n. sp,

Cephalis small, hemispherical, with small, irregular, polygonal pores. Thorax flatly pyramidal,
nearly discoidal, with nine prominent, stout ribs, which are connected by numerous (twelve to six-
teen) horizontal, nine-angled rings. In the outer half of the thorax there are nine weaker secondary
ribs interpolated between the nine stronger primaries, and eighteen shorter and feebler tertiary ribs
between the former and the latter. Peristome denticulated, nine-angled.

Dimensions. — Cephalis 0'03 diameter, thorax 0'08 long, 0'24 broad..

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

14. Sethophormis eupilium, n. sp. (PL 56, fig. 9).

Sethopyramis eupilium, Haeckel, 1882, Atlas, pi. Ivi. fig. 9.
Craspedilium eupilium, Haeckel, 1878, Manuscript.

Cephalis very small, hemispherical, hyaline, without pores. Thorax flatly pyramidal, with nine
concave, triangular faces and nine little curved, stout, radial beams. Between these are interpolated
numerous incomplete secondary beams, which are absent in the apical part of the thorax. The radial
beams being connected by numerous (thirty to forty or more) horizontal, ring-like threads, a delicate,
arachnoidal network with small, quadrangular pores is produced. Peristome nine-angled, with a
peculiar vertical gallery, composed of four horizontal, parallel, nine-angled rings, which are con-
nected by numerous vertical, parallel bars, therefore with three transverse rows of square pores.
This peculiar species is very different from the preceding and may represent a separate genus,
Craspedilium,.

Dimensions. — Cephalis O'Ol diameter, thorax 01 long, 0'25 broad.

Habitat. — Central Pacific, Station 271, surface.

1248 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 6. Astrophormis, Haeckel.

Definition. — Thorax with a variable number of radial ribs (twelve to twenty or
more).

15. Sethophormis aurclia, n. sp. (PJ. 55, figs. 3, 4).

Leptarachnium aurelia, Haeckel, 1879, Manuscript et Atlas.

Cephalis large, nearly hemispherical, with irregular, delicate network of small square meshes.
Collar-septum with four large meshes, separated by a cross of four bars, opposite in pairs. Thorax
flatly campanulate, with delicate, subregular, hexagonal meshes, and twenty-four prominent radial
ribs ; four of these are primary or perradial (centrifugal prolongations of the four bars of the collar-
septum); four others are interradial or secondary, alternating with the former at angles of 45°;
sixteen others are adradial or tertiary, interpolated between the first and second more or less irre-
gularly. In some specimens the disposition of the twenty-four ribs was more regular, in others more
irregular, than in the specimen figured (figs. 3, 4). The central capsule (fig. 4) exhibits a flat, cap-
shaped part with the nucleus (enclosed in the cephalis), and four large, pear-shaped lobes protruded
through the four large collar holes (somewhat deformed in the preparation figured). The wall of the
thorax exhibits at the base four larger, nearly semicircular pores, bisected by the four primary
thoracic ribs. Peristome with twenty-four indentations (between the prominent distal ends of the
twenty-four ribs), often more distinct than in ttie specimen figured.

Dimensions. — Cephalis O03 long, O08 broad ; thorax 01 to 0'2 long, 0'4 to 0'6 broad.

Habitat. — Central Pacific, Station 263 to 274, depth 2350 to 2925 fathoms.

16. Sethophormis dodecaster, n. sp. .(PI. 56, fig. 12).

Cephalis small, flatly cap-shaped, with irregular, small, roundish pores. Thorax flatly conical,
nearly of the same shape as in -the preceding species, but. only with twelve prominent ribs; four
primary or perradial ribs (as prolongations of the four crossed cortinar bars), and eight adradial ribs
interpolated between the former, and arising at some distance from the collar ring. Peristome with
twelve prominent pointed lobes {supported by the distal ends of the twelve ribs), and with twelve
semicircular bosoms between them. (The specimen figured is young and not fully developed.)

Dimensions. — Cephalis 0'02 long, 0'04 broad ; thorax 01 long, 0'3 broad.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

,17. Sethophormis umbrella, n. sp. (PI. 70, figs. 4, 5).

Cephalis large, flatly cap-shaped, with irregular, small polygonal meshes. Thorax flat, umbrella-
shaped, with subregular, hexagonal meshes, and sixteen strong radial ribs. Four of these are per-
radial, and centrifugal prolongations of the four crossed collar beams ; four others are interradial, and

REPORT ON THE RADIOLARIA. 1249

arise, alternating with the former, directly from the horizontal collar ring ; eight ribs are adradial or
tertiary, and arise in pairs from the four large perradial basal arches of the thorax, which become
bisected by the four primary ribs. Peristome irregularly denticulate.

Dimensions. — Cephalis 0'02 long, 0'06 broad ; thorax 0'12 long, 0'32 broad.

Habitat. — North Pacific (off Japan), Stations 236 to 239, surface.

18. Sethophormis floscula, n. sp.

Cephalis small, hemispherical, with subregular, small hexagonal pores. Thorax flatly conical, with
larger hexagonal meshes and twenty-four ribs ; four of these are perradial and prolongations of the
four collar bars ; four interradial arise from the collar ring between the former, alternating with them.
Each of these eight main ribs gives off two more or less irregular, lateral branches (one at each side),
altogether sixteen. The thorax is similar to Cladarachnium ramosum (PL 55, fig- 5), whilst the
cephalis is quite different. Peristome with twenty-four prominent triangular lobes.

Dimensions. — Cephalis 0'02 long, O'OS broad ; thorax O'l long, 0'4 broad.

Habitat. — South Atlantic, Station 325, surface.

19. Sethophormis leptoscenium, n. sp.

Cephalis very small, spherical, with few small, circular pores. Thorax flatly conical or tent-
shaped, with concave lateral outlines, small hexagonal meshes, and numerous (thirty to forty or
more) strong, little curved, simple radial ribs. Peristome nearly circular, with a corona of small,
irregular, conical spines.

Dimensions. — Cephalis O'OIS diameter ; thorax 0'07 long, 0-26 broad.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

20. Sethophormis leptopilium, n. sp.

Cephalis very small, subspherical, hyaline, without pores. Thorax flatly conical or hat-shaped,
with concave lateral outlines, and a very delicate network of small square meshes (similar to
Litharachnium araneosum, PL 55, fig. 8). This is supported by thirty-two curved radial ribs, four
of which are primary, four secondary, and the other twenty-four interpolated. Peristome horizon-
tally expanded and little recurved, like the reflexed brim of a hat.

Dimensions. — Cephalis 0'12 diameter ; thorax 0~08 long, 0'24 broad.

Habitat. — South Pacific, Station 291, depth 2250 fathoms.

Genus 559. Sethamphora,1 n. gen.

Definition. — S ethophormida (vel Dicyrtida rnultiradiata aperta) with numerous
curved ribs in the wall of the ovate thorax, the small mouth of which is constricted.
Cephalis without horn.

1 Sethamphora = Sieve-pitcher ; aqUa, a^pojei/'j.
(ZOOL. CHALL. BXP. — PART XL. — 1886.) Er 157

1250 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Sethamphora differs from the preceding Sethophormis, and from the next
following ribbed Sethophormida, mainly in the small, more or less constricted mouth ;
therefore the thorax is more or less ovate, and its ribs curved, with the convexity external.
Sethophormis may be divided into two different subgenera, Dictyoprora and Cnjpto-
cephalus; in the former the cephalis is perfectly free and well developed, in the latter
it is more or less hidden in the uppermost part of the thorax (like Carpocanium).

Subgenus 1. Dictyoprora, Haeckel, 1881, Prodromus, p. 430.
Definition. — Cephalis large, perfectly free, not hidden in the thorax.

1. Sethamphora hexapleura, n. sp.

Shell ovate, smooth, with distinct collar stricture. Length of the two joints = 3: 11, bread th =
5:10. Cephalis large, free, hemispherical, with small circular pores. Thorax truncate, ovate, with
six strong curved ribs, and six large triangular meshes between them in the upper half ; five smaller
pores between every two ribs in the lower half (in three tiers); therefore, together, thirty-six
thoracic meshes. Mouth strongly constricted, smooth, only one-third as broad as the thorax.

Dimensions. — Cephalis 0'03 long, 0'05 broad ; thorax, Oil long, 01 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Sethamphora enneapleura, n. sp.

Shell subovate, smooth, with1 slight collar stricture. Length of the two joints = 3 : 9, breadth =
4 : 8. Cephalis large, hemispherical, free, with small circular pores. Thorax inflated, ovate, with
nine strong curved ribs, which are connected by five transverse circular rings at equal distances.
Forty-five rounded, squarish, large meshes between them, in five transverse and nine longitudinal
rows. Mouth constricted, smooth, half as broad as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'09 long, 0'08 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

3. Sethamphora dodecapleura, n. sp.

Shell urceolate, smooth, with sharp collar stricture. Length of the two joints = 3:9, breadth
= 5:9. Cephalis flat, cap-shaped, free, with twelve ribs, and very small pores between them.
Thorax thick -walled, inflated, with subcylindrical cavity, and twelve prominent sharp ribs, alternating
with twelve longitudinal rows of very small circular pores (eight pores in each row). Mouth con-
stricted, half as broad as the thorax.

Dimensions. — Cephalis 0'03 long, 0'05 broad ; thorax 0'09 long, 0'09 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

REPORT ON THE RADIOLARIA. 1251

V

4. Sethamphora mongolfieri, Haeckel.

Eucyrtidium mongolfieri, Ehrenberg, 1854, Mikrogeol., Taf. xxxiv. fig. 18; Abhandl. d. k.
Akad. d. Wiss. Berlin, 1875, p. 72, Taf. x. fig. 3.

Shell urceolate, smooth, with distinct collar stricture. Length of the two joints = 2:9, breadth
= 3:7. Cephalis campanulate, with eighteen ribs and small pores. Thorax nearly ellipsoidal, with
eighteen prominent ribs, and eighteen longitudinal rows of regular circular pores between them
(eight pores in each row ; therefore 144 pores altogether). Mouth constricted, only one-third as broad
as the thorax.

Dimensions. — Cephalis 0'02 long, 0'03 broad; thorax 0'09 long, 0'07 broad.

Habitat. — Fossil in Barbados.

5. Sethamphora costata, n. sp.

Shell urceolate, smooth, very similar to the preceding species ; also with eighteen longitudinal
ribs, but differing in the larger size of the cephalis and its pores, and in the more slender and ovate
form of the thorax. Length of the two joints = 5 : 10, breadth = 5 : 8. Pores of the cephalis more
numerous. Mouth half as broad as the thorax.

Dimensions. — Cephalis 0'05 long, 0'05 broad ; thorax O'l long, 0'08 broad.

Habitat. — Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

6. Sethamphora serrata, n. sp.

Shell ovate, spinulate, without external collar stricture. Length of the two joints = l:6,
breadth = 2:4. Cephalis flat, cap-shaped, with small circular pores. Thorax ovate, truncate,
with eighteen serrate longitudinal ribs, alternating with eighteen longitudinal rows of short and
broad rather oblong pores (twenty to thirty pores in each row). Mouth strongly constricted, only
one-fourth as broad as the thorax.

Dimensions. — Cephalis 0'02 long, 0-04 broad ; thorax 012 long, 0'08 broad,

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

7. Sethamphora ampulla, Haeckel.

Eucyrtidium ampulla, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 15; Abhandl. d. k. Akad.
d. Wiss. Berlin, 1875, p. 72, Taf. x. figs. 11, 12.

Shell broad, urceolate, spiny, with sharp collar stricture. Length of the two joints = 1:4,
breadth = 1 : 5. Cephalis subspherical, with few small pores (in figs. 12«. and 12J of Ehrenberg, loc. cit.,
broken off, so that the four pores of the cortinar septum appear). Thorax inflated, bottle-shaped, with
twenty prominent, sharply dentate ribs, alternating with twenty longitudinal rows of circular pores
(about eight pores in each row). Mouth flat, constricted, one-third as broad as the thorax.

Dimensions. — Cephalis 0'025 long, Q'03 broad ; thorax O'l long, 0'14 broad.

Habitat. — Fossil in Barbados.

1252 THE VOYAGE OF H.M.S. CHALLENGER.

8. Sethamphora aerostatica, Haeckel.

Podocyrtis aerostatica, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xvi.
fig. 4.

Shell broad, urceolate, smooth, with sharp collar stricture. Length of the two joints = 2:6,
breadth = 3:8. Cephalis hemispherical, large, with few pores (broken off in fig. 4a of Ehrenberg, so
that the six collar pores appear). Thorax inflated, bottle-shaped, with twenty-two to twenty-four
smooth prominent ribs, alternating with the same number of longitudinal rows of small circular pores.
Mouth very small, strongly constricted, scarcely as broad as the cephalis, with three short teeth.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 006 long, 0'08 broad.

Habitat. — Fossil in Barbados.

Subgenus 2. Cryptocephalus, Haeckel, 1881, Prodromus, p. 430.

Definition. — Cephalis more or less hidden in thorax, being partly enveloped by its
uppermost part.

9. Sethamphora microstoma, n. sp. (PL 57, fig. 5).

Cryptoprora microstoma, Haeckel, Atlas, pi. Ivii., fig. 5.

Shell ovate, smooth, without external collar stricture. Length of the two joints = 1:6, breadth =
2 : 4. Cephalis flat, cap-shaped, without ribs, with small circular pores. Thorax ovate, with twenty-
four prominent ribs, alternating with deep longitudinal furrows, each of which contains a series of
about fifteen small circular pores. Mouth very small, representing a short cylindrical tube, which
is only one-eighth as broad as the thorax.

Dimensions. — Cephalis 0'02 long, O04 broad ; thorax 012 long, 0'08 broad.

Habitat. — Western Tropical Pacific, Station 220, depth 1100 fathoms.

10. Sethamphora favosa, n. sp. (PI. 57, fig. 4).

Cryptocephalus favosus, Haeekel, 1881, Prodromus, p. 430.

Shell ovate, dimply. Length of the two joints =1:5, breadth = 1:5. Cephalis subspherical,
small, completely hidden in the thickened top of the thorax (but very distinct in the longitudinal
section). Thorax ovate, with, twenty-five to thirty longitudinal ribs, alternating with the same number
of longitudinal furrows, each of which contains ten to twelve circular, hexagonally framed pores.
In the smooth wall of the peristome only twelve triangular ribs are visible. Mouth constricted,
one-third as broad as the thorax.

Dimensions. — Cephalis 0'02 diameter ; thorax 01 long, 009 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

REPORT ON THE RADIOLARIA.. 1253

Genus 560. Sethopyramis,1 Haeckel, 1881, Prodromus, p. 432 (sensu emendate !)

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) with nume-
rous straight or slightly curved radial ribs in the wall of the pyramidal thorax. Net-
work simple. Cephalis commonly without horn.

The genus Sethopyramis and the four following genera form together a peculiar
small group (Sethopyramida), characterised by the slender pyramidal shell, in the wall
of which numerous (six to nine or more) radial ribs are enclosed. These ribs may be
regarded as the terminal feet of a Calpophcena or Halicalyptra, which become connected
by transverse bars. Sethopyramis may be derived also directly from Patagospyris by
loss of the primary sagittal ring and reduction of the cephalis.

Subgenus 1. Sestropyramis, Haeckel.

Definition. — Pyramidal shell with six radial main beams (sometimes also five or
seven, as individual varieties).

1. Sethopyramis scalaris, Haeckel..

Carnuidla scalaris, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii. fig. 1.

Shell smooth, slenderly pyramidal, hexagonal. Cephalis large, subglobular, hyaline, without
pores (or with very small and scarce pores). Thorax with six straight (or little curved) stout
longitudinal ribs or radial beams, which are connected by twenty to thirty complete, hexagonal,
horizontal rings. The large meshes so produced are regular, square, their length and breadth
equally and gradually increasing towards the mouth.

Dimensions. — Cephalis 0-04 diameter ; thorax (with twenty-four transverse rings) 0'4 long,
015 broad at the mouth.

Habitat. — Fossil in Barbados.

2. Sethopyramis hexalactis, n. sp.

Shell thorny, of the same form as, and similar structure to, the preceding species, but differing
in the spiny surface and the smaller subglobular cephalis, which bears small circular pores and an
oblique conical horn twice the length. The whole surface is covered with short conical thorns.

Dimensions.- — Cephalis 0'02 diameter ; thorax (with twenty transverse rings) 0'25 long, 01 broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Subgenus 2. Cephalopyramis, Haeckel, 1881, Prodromus, p. 432.

Definition. — Pyramidal shell with nine radial main beams (sometimes also eight or

ten, as individual varieties).

1 Sethopyramis = Sieve-pyramid ; oqfa,

THE VOYAGE OF H.M.S. CHALLENGER.

3. Seihopyramis enneactis, n. sp. (PI. 56, fig. 7).

Cephalopyramis enneactis, Haeckel, 1881, Prodromus et Atlas, pi. Ivi. fig. 7.

Shell smooth, slender, pyramidal. Cephalis large, ovate, with pointed apex, nearly hyaline,
with very few and small scattered pores. Thorax very slenderly pyramidal, with straight lateral
outlines, and nine stout and straight radial beams, which are connected by fifteen to twenty
horizontal complete rings. Meshes subregular, square, simple, without secondary network ; their
length and breadth equally increasing towards the mouth.

Dimensions. — Cephalis 0'05 long, 0'03 broad ; thorax (with twenty transverse rings) 0'24 long,
O'l broad at the mouth.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

4. Seihopyramis quadrata, n. sp. (PL 54, fig. 2).

Shell smooth, slenderly pyramidal, very similar in form and structure to the preceding species ;
differing from it in the rudimentary cephalis, which is very small, hemispherical, with few small
porules. The three internal cortinar bars of the collar stricture are present ; when they become
lost this species passes over into Bathrapyramis quadrata (PI. 54, fig. 1).

Dimensions. — Cephalis O'Ol long, 0'02 broad; thorax (with ten transverse rings) 015 long,
O'l broad at the mouth.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

5. Sethopyramis guadratella, HaeckeL

Cornutella, quadratella, Ehrenberg, 1875, Abhandl d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii.
fig. 2.

Litharachnium quadratella, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 540, Taf.
xxxiii. fig. 37.

Shell smooth, broadly pyramidal. Cephalis ovate, small, blunt, hyaline, with very few and small
pores (in the figure of Ehrenberg brdken off). Thorax broadly pyramidal, with straight lateral out-
lines, and nine stout and straight radial beams, which are connected by -eight to twelve horizontal
complete rings. Meshes in the upper half regular, square, in the lower half broad, rectangular (in
the tenth transverse row twice as broad as long).

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax (with ten transverse rings) 015 long,
015 broad.

Habitat. — Fossil in Barbados.

6. Sethopyramis trapezoides, .n. sp.

Shell smooth, broadly pyramidal. Cephalis large, ovate, hyaline, without pores; its collar
septum exhibits distinctly the four collar pores (two larger cardinal and two smaller jugular pores).

REPORT ON THE RAD10LARIA. 1255

*

Thorax broad, pyramidal, with slightly concave lateral outlines and nine (sometimes eight or ten)
curved ribs, which are connected by eighteen to twenty-four complete transverse rings. The large
meshes, so produced, have the form of a parallel trapezoid, and are in the eighth transverse row
three times as broad as long. (Differs from Bathropyramis trapezoides, PI. 54, fig. 3, mainly by the
possession of a well developed cephalis).

Dimensions. — Cephalis 0'04 long, O03 broad ; thorax (with eighteen rings) 0'32 long, 0'24 broad.

Habitat. — South Pacific, Station 285,, depth 2375 fathoms.

7. Sethopyramis spinosa, n. sp.

Shell thorny, slender, pyramidal. Cephalis small, subspherical, with few small pores and a
straight, vertical, conical horn twice the length. Thorax with nine straight ribs, which are con-
nected by sixteen to twenty complete transverse nine-angled rings. The large meshes so produced
are subregular, square. From each nodal point a short conical spine arises. (Differs from the
similar Bathropyramis spinosa, PI. 54, fig. 4, by the development of the cephalis and the simple
pointed, unforked spines.)

Dimensions. — Cephalis 0'03 diameter; thorax (with sixteen rings) 0'2 long, 0'12 broad.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

8. Sethopyramis hexagonalis, n. sp.

Shell papillate, slender, pyramidal. Cephalis small, hemispherical, with a straight conical
horn twice the length, and small circular pores. Thorax conical, with slightly convex outlines and
nine stout, somewhat curved ribs in zig-zag form, which are connected by ten to twelve interrupted
transverse bars. From each nodal point a small conical papilla arises. The large meshes so pro-
duced are regular, hexagonal, gradually increasing in size towards the mouth.

Dimensions. — Cephalis 0'03 diameter ; thorax (with twelve transverse rows of meshes) 018 long,
012 broad.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

9. Sethopyramis cyclomma, n. sp.

Shell thorny, slender, pyramidal Cephalis large, subspherical, with numerous very small
circular pores, and a small conical horn of the same length. Thorax similar in form and structure
to that of the preceding species ; but each hexagonal mesh is provided with a very thin circular
hyaline ring (Like a diaphragm), so that the openings are not hexagonal, but circular. From each
nodal point a short pointed conical or slightly forked spine arises.

Dimensions. — Cephalis 0'02 diameter ; thorax (with ten transverse rows of meshes) 018 long,
014 broad.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

1256 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 3. Actinopyramis, Haeckel.

Definition. — Pyramidal shell with twelve or more radial beams (commonly twelve to
twenty-four, sometimes forty or more).

10. Sethopyramis dodecalactis, n. sp.

Shell smooth, slender, pyramidal. Cephalis small, spherical, hyaline, with a short conical horn.
Thorax with twelve radial ribs in the upper half, between which twelve others are interpolated in
the lower half. These are connected by twenty to twenty-four complete transverse rings. The
meshes so produced are subregular, rectangular.

Dimensions. — Cephalis 0'03 diameter ; thorax 0'6 long, 0'2 broad.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

11. Sethopyramis bicornis, n. sp.

Shell spiny, slender, pyramidal. Cephalis small, spherical, hyaline, with two divergent conical
horns, the major (occipital) three times and the minor (frontal) twice as long. Thorax slender,
pyramidal, campanulate, thorny, with twenty to thirty radial beams, which are little curved, convex
in the upper, concave in the lower half, and connected by numerous interrupted transverse bars.
Meshes in the upper third rounded, in the lower two-thirds quadrangular, of very different sizes.
Surface covered with spinules.

Dimensions. — Gephalis O02 diameter ; thorax O9 long, 0-4 broad.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

12. Sethopyramis maxima, n. sp.

Shell smooth, slender, pyramidal. Cephalis small, spherical, with few small pores, and a stout,
vertical, conical horn twice the length. Thorax very prolonged, conical, with straight lateral out-
lines and numerous (twenty to fifty) radial beams (in the upper third twelve, in the middle third
twenty-four, in the lower third forty to fifty, by interpolation); they are connected by very numerous
interrupted transverse bars. Meshes subregular, quadrangular. Surface smooth.

Dimensions. — Cephalis 0'02 diameter ; thorax T05 long, 0'45 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 561. Plectopyramis,1 Haeckel, 1881, Prodromus, p. 432.

Definition, — S ethophormida (vel Dicyrtida multiradiata aperta) with numerous
straight or slightly curved radial ribs in the wall of the pyramidal thorax. Network
double, the large primary meshes being fenestrated by fine secondary network. Cephalis
commonly without horn.

1 Plectopyramis = Woven pyramid ; •^AEXTO'S, wt/ja^iV.

REPORT ON THE RADIOLARIA. 1257

The genus Plectopyramis differs from the preceding Sethopyramis, its ancestral form,
only in the peculiar double fenestration of the shell, the large primary meshes of which
are separated by strong bars, and filled up by a very delicate arachnoidal network, com-
posed of small pores and very thin threads between them. This double lattice-work
often exhibits a very remarkable regularity. As in the preceding genus, the number of
radial ribs is commonly six or nine, rarely twelve to twenty or more.

Subgenus 1. Hexapleuris, Haeckel.

Definition. — Pyramidal shell with six radial main beams (sometimes five or seven
in individual varieties).

1. Plectopyramis magnified, Haeckel.

folycystiiia magnified, Bury, 1862, Polyeystins of Barbados, pi. xi. fig.

Shell smooth, slender, pyramidal. Cephalis large, ovate, pointed, separated from the thorax
by a very deep collar stricture, with few irregular pores. Thorax with six strong and straight
radial beams, which are connected by about twenty horizontal, hexagonal rings. The large meshes
so produced are regular, square, and filled up by an extremely delicate secondary arachnoidal net-
work, composed of regular square pores (as in PL 54, figs. 7, 8).

Dimensions. — Cephalis 0'06 long, 0'04 broad ; thorax (with twenty transverse rings) 0'4 long,
012 broad.

Habitat. — Fossil in Barbados.

2. Plectopyramis hexapleura, n. sp.

Shell thorny, slender, pyramidal. Cephalis large, ovate, blunt, with deep collar stricture.
Thorax with six strong and straight radial beams, which are connected by numerous (twenty to
thirty) interrupted transverse bars. The large meshes so produced are irregular, quadrangular, and
filled up by irregular, delicate, secondary network, with small polygonal pores.

Dimensions. — Cephalis O'Oo long, O03 broad ; thorax 0'3 long, O'l broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Subgenus 2. Enneapleuris, Haeckel.

Definition. — Pyramidal shell with nine radial main beams (sometimes eight or ten
in individual varieties).

(ZOOL. CHALL. KXP. — PART XL. — 1886.) Rr 158

1258 THE VOYAGE OF H.M.S. CHALLENGER.

3. Plectopyramis dodecomma, n. sp. (PL 54, fig. 6).

Shell smooth, slenderly pyramidal, with straight outlines. Cephalis conical, obtuse, with thirty-six
small square pores (in nine divergent longitudinal rows, each of four pores). Collar septum (be-
tween cephalis and thorax) with four distinct collar pores. Thorax pyramidal, with nine very stout
and straight angular radial beams, which are connected by ten to fifteen broad horizontal nine-
angled rings. Each of the large regular, square meshes so produced contains a very delicate fenestra-
tion, with twelve regular, square pores, separated by two transverse and three longitudinal crossed
threads. A very regular and remarkable structure.

Dimensions. — Cephalis 003 long, OD2 broad ; thorax (with ten rings) 0'2 long, 015 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Plectopyramis quadratomma, n. sp.

Shell smooth, slenderly pyramidal. Cephalis large, ovate, hyaline, with few very small basal
pores and deep collar stricture. Thorax pyramidal, with straight outline, and nine very stout and
straight radial beams, which are connected by fifteen to twenty horizontal nine-angled rings. Each of
the large regular, square meshes so produced is filled up by a very delicate arachnoidal network,
with very numerous and small square pores (as in the similar Cindopyramis infundibulum, PL 54,
fig. 7, which differs in the loss of the cephalis).

Dimensions. — Cephalis 0'05 long, 0'03 broad; thorax (with fifteen rings) 0'32 long, 0'2 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

5. Plectopyramis trapezomma, n. sp. (PI. 54, fig. 8).

Shell smooth, broadly pyramidal, with concave lateral outlines. Cephalis hemispherical, small,
with numerous small, circular pores. Thorax pyramidal, with nine stout, concavely curved radial
beams, which are connected by twelve to sixteen horizontal nine-angled rings. The large meshes so
produced are in the upper half square, in the lower half parallel trapezoid (in the fifteenth ring
three times as broad as long), and filled up by a secondary arachnoidal network, with very numerous
and small square pores.

Dimensions. — Cephalis 0'015 long, 0'025 broad ; thorax (with fifteen rings) 0'22 long, 0'2 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

6. Plectopyramis poly gonomma, n. sp.

Shell smooth, pyramidal, very similar to the preceding species ; differing from it in the irregular
shape of the delicate polygonal (not tetragonal) secondary network, filling up the large rectangular
meshes. The cephalis is larger, hyaline, pear-shaped, pointed, without pores, with a deep collar
stricture. The nine radial beams of the thorax are less concave.

Dimensions. — Cephalis 0'04 long, 0'03 broad ; thorax (with fifteen rings) 0'3 long, 0'22 broad.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

REPORT ON THE RADIOLARIA. 1259

7. Plectopyramis heteromma, n. sp.

Shell smooth, slenderly pyramidal, with concave outlines. Cephalis very small, subspherical, with
a small oblique, conical horn, and very small, scarce circular pores. Thorax with nine stout con-
cavely curved radial beams, which are connected by numerous (thirty to fifty or more) interrupted
transverse bars. The large irregular meshes so produced are filled up by irregular, polygonal,
delicate lattice-work.

Dimensions. — Cephalis 0'02 long, 0'02 broad; thorax 0'6 long, 0'3 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

8. Plectopyramis serrata, n. sp.

Shell thorny, slenderly pyramidal, with straight outlines. Cephalis very small, spherical, with a
long oblique, conical horn, and very small circular pores. Thorax with nine stout, straight, regularly
serrate ribs or radial beams, which are connected by numerous (twenty to thirty or more) inter-
rupted transverse bars. The latter, being crossed by intercalated and interrupted irregular radial
beams, produce a subregular secondary network of rectangular meshes of different sizes.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax, 0'3 long, 0'2 broad.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

9. Plectopyramis fenestrata, Haeckel.

Pyramis fenestrata, Bury, 1862, Polycystins of Barbados, pi. xxi. fig. 8.

Shell thorny, broadly pyramidal, with straight outlines. Cephalis very small, spherical, hyaline.
Thorax with nine stout, spinulate, straight ribs or radial beams, which are connected by ten to fifteen
transverse bars, which in the upper half are complete rings, in the lower half interrupted, and
crossed by irregularly intercalated radial beams. Meshes therefore irregular, quadrangular. All
the bars are thorny.

Dimensions. — Cephalis O'Ol diameter ; thorax 0'2 long, 016 broad.

Habitat. — Tropical Atlantic.

10. Plectopyramis furcata, n. sp.

Shell spiny, slenderly pyramidal, with straight outlines. Cephalis small, spherical, with few
small pores. Thorax with nine stout and straight spinulate ribs, which are connected by a variable
number of irregular interrupted transverse bars ; the large quadrangular meshes so produced are
filled up by irregular delicate network. The entire surface of the thorax is covered with short
forked spines.

Dimensions. — Cephalis 0'02 diameter ; thorax 0'3 long, 0'2 broad.

Habitat. — Indian Ocean (Zanzibar), Pullen, depth 2200 fathoms.

1260 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 3. Polypleuris, Haeckel.

Definition. — Pyramidal shell with numerous (twelve or more) radial main beams
(commonly twelve to eighteen, sometimes twenty to thirty or more).

11. Plectopyramis poly pleura, n. sp. (PI. 56, fig. 8).

Shell smooth, slenderly conical, with straight outlines. Cephalis small, subspherical, with very
small dot-like pores, and an oblique conical horn twice the length. Thorax with numerous
(twenty to thirty) divergent longitudinal ribs; usually twelve of these radial beams appear as
stronger, primary main ribs, and twelve to eighteen other as secondary, feebler, interpolated ribs.
They are crossed by numerous (twenty to forty or more) horizontal rings. The large meshes so
produced are quadrangular, and partly filled up by a very delicate secondary network, with small
square pores.

Dimensions. — Cephalis 0'03 diameter; thorax 0'36 long, 0'24 long.

Habitat. — Central Pacific, Station 267, depth 2700 fathoms.

12. Plectopyramis lagena, n. sp.

Shell smooth, wine-bottle shaped, or slenderly conical-campanulate, with bent outlines, which are
concave in the upper, convex in the lower half. Cephalis very small, spherical, hyaline, without
pores. Thorax with twenty-four radial ribs, twelve stronger primary, alternating with twelve feebler
secondary. They are crossed by interrupted transverse bars. The irregular quadrangular meshes
so produced are filled up by a delicate, irregular, secondary network.

Dimensions. — Cephalis 0'02 diameter ; thorax 0'5 long, 0'3 broad.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

Genus 562. Spongopyramis,1 n. sp.

Definition.— -S ethophormida (vel Dicyrtida multiradiata aperta) with numerous
straight or slightly curved radial ribs in the wall of the pyramidal thorax. Network
spongy. Cephalis commonly without horn.

The genus Spongopyramis has arisen from Sethopyramis by development of an
irregular spongy framework around the lattice-shell, and is one of the small number of
Cyrtoidea in which the shell-wall exhibits a spongy structure. In both observed
species the cephalis is small, but evident.

1 Spongopyramis=Spongy pyramid ; ja-oyyof,

REPORT ON THE RADIOLARIA. 1261

1. Spongopyramis spongiosa, n. sp. (PI. 56, fig. 10).

Plectopyramis spongiosa, Haeckel, 1881, Prodromus et Atlas, loc. cit.

Shell partly or entirely enveloped by spongy framework, slender, pyramidal, with rather straight
outlines. Cephalis very small, ovate, hyaline. Thorax with nine very stout and nearly straight
ribs, which are connected by fifteen to twenty or more irregular, interrupted transverse bars. The
irregular quadrangular meshes so produced are filled up by an irregular secondary network, with
meshes of very different size and form. The dense spongy envelope, which in the specimen figured
covered only half the shell, was complete in another older specimen.

Dimensions. — Cephalis O015 long, O01 broad; thorax 0-4 long, 0'25 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Spongopyramis spongoplecta, n. sp.

Shell entirely enveloped by spongy framework, pyramidal, with straight outlines. Cephalis
ovate (twice as large as in the preceding species), with small circular pores. Thorax with twelve
stout and straight ribs, which are connected by twenty to twenty-five annular, transverse bars.
The subregular square meshes so produced are filled up by irregular, spongy network, which
envelops the whole shell more loosely than in Spongopyramis spongiosa.

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 0'5 long, 0'2 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 563. Acanthocorys,1 Haeckel, 1881, Prodromus, p. 432.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) with numerous
radial ribs in the wall of the pyramidal thorax, prolonged into divergent terminal feet.
Network simple. Cephalis commonly with several horns.

The genus Acanthocorys and the following nearly allied Arachnocorys possess a near
relation to the three preceding pyramidal genera, but differ from them in the terminal pro-
longation of the radial ribs, which are commonly spiny and form a corona of free feet
around the mouth of the thorax. The cephalis is usually much larger than in the three
preceding genera, and bears a variable number of radial horns. Therefore these two genera
are probably older and nearer to the common ancestral form of the Sethophormida
than the preceding genera. It may be derived directly from Dictyophimus by inter-
polation of three secondary (interradial) ribs between the three primary (perradial) ribs.

1 Acanthocorys = Spiny helmet ; a.x.a.ii6», wy/;.

1262 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 1. Acanthocorallium, Haeckel.

Definition. — Thorax with six divergent ribs or radial beams (three primary or perradial
alternating with three secondary or interradial).

1. Acanthocorys hexapodia, n. sp.

Cephalis large, ovate, with subregular hexagonal pores, and six strong, conical, simple, divergent
horns of the same length. Thorax flat, conical, smooth, with six large triangular basal holes, sepa-
rated by six strong, prismatic, smooth beams, which are connected only near the distal end by a
hexagonal ring of delicate, irregular network. "Collar septum with three meshes, separated by the
three centripetal prolongations of the three primary ribs.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 0'12 long, O24 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

2. Acanthocorys pristipodia, n. sp.

Cephalis large, hemispherical, with irregular, polygonal pores, and numerous (ten to twenty) bristle-
shaped, radiating horns, which are conical at the base, and twice as long. Thorax flatly campanulate,
thorny, with six strong, serrate or spinulate, divergent, radial ribs, prolonged into six free conical
feet of the same length. Meshes of the thorax irregular, polygonal, a corona of six larger ones at
the base. Collar septum with four meshes, shaped as in PI. 56, fig. 6.

Dimensions. — Cephalis 0'04 long, 0'06 broad ; thorax O08 long, 018 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

3. Acanthocorys macropodia, n. sp.

Cephalis small, subspherical, with irregular, roundish pores and numerous small, bristle-shaped
horns. Length of the two joints = 1:2, breadth = 1:6. Thorax sexangular, pyramidal, with six
very long and straight, widely divergent feet, which are prismatic and spiny, and three to five times
as long as the breadth of the shell. Only the upper third of the six ribs is connected by irregular,
roundish network, with six large triangular holes at the base. Collar septum with four meshes
which have the same relation to the six ribs as in Sethophormis hescalactis (PI. 56, fig. 6).

Dimensions. — Cephalis 0'025 diameter, thorax 0'05 long, 0'15 broad.

Habitat. — Central Pacific, Station 271, surface.

4. Acanthocorys btitschlii, Haeckel.

? Clathrocanium ehrenbergii, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvL pp. 514, 539,
Taf. xxxii. fig. 18, a, b.

Cephalis large, subspherical, with numerous small, circular pores and three to six divergent,
slender, apical horns. Thorax flatly conical, smooth, not much larger than the cephalis, with six

REPORT ON THE RADIOLARIA. 1263

large, triangular or ovate basal holes between the six ribs. Three of these ribs are primary or
perradial, and arise immediately from the collar septum, alternating with three secondary or inter-
radial ribs, which arise more outside. The specimen observed by me exhibited six apical horns,
and was more complete than that figured by Blitschli, the six ribs being prolonged over the con-
necting lattice-girdle into six short, divergent feet.

Dimensions. — Cephalis 0'06 long, O06 broad ; thorax 008 long, 01 broad.

Habitat. — Fossil in Barbados.

Subgenus 2. Acanthocoronium, Haeekel.

Definition. — Thorax with nine divergent ribs or radial beams, three of which are
primary or perradial, the other six secondary or interradial.

5. Acanthocorys umbellifera, Haeekel.

Arachnocorys umbellifera, Haeekel, 1862, Monogr. d. Radiol., p. 305, Taf. vi. fig. 12.

Cephalis large, ovate, with subregular, circular pores and numerous divergent, simple spines of
different lengths. Thorax flatly conical, with nine strong, divergent ribs, which in the distal half are
free, in the proximal half connected by numerous transverse beams, forming irregular polygonal
meshes. Dorsal face of the thorax armed with scattered ascending spines.

Dimensions. — Cephalis 0'05 long, 0'035 broad ; thorax 0'05 long, 0'12 broad.

Habitat. — Mediterranean (Messina) ; Atlantic, Station 354, surface.

6. Acanthocorys triloba, n. sp.

Cephalis large, campanulate, trilobed, with irregular, roundish pores, numerous spines, and a
large pyramidal horn on the top, which is connected by three constricted arches with the base of
the horizontal collar beams. From the latter arise as centrifugal prolongations three stout, curved,
primary ribs of the flatly vaulted thorax, and each of these gives off at the base two opposite, lateral,
secondary ribs. These nine ribs are spiny, and connected by irregular, arachnoidal network.

Dimensions. — Cephalis 0'05 long, 0'07 broad ; thorax 0'08 long, 018 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

7. Acanthocorys enneapodia, n. sp.

Cephalis large, ovate, with irregular roundish pores, and numerous divergent, ascending spines.
Thorax smooth, conical, little larger, with the same network, and nine larger, triangular holes at
the base ; with nine straight, equally-disposed ribs, which are prolonged into slender feet twice
the length. With these latter alternate nine shorter radial spines, arising from the truncate
peristome.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 0'05 long, 0'09 broad.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

1264 THE VOYAGE OF H.M.S. CHALLENGER.

8. Acanthocorys macroceras, n. sp. (PI. 97, fig. 12).

Cephalis large, hemispherical, spiny, with regular, circular pores, and a very large, cylindrical,
vertical horn five times as long as the whole shell. Thorax spiny, campanulate, with
irregular, roundish pores and nine strong, curved ribs, prolonged into nine slender, divergent feet
twice the length, which are curved, convex in the proximal half and concave in the distal half.

Dimensions. — Cephalis 005 long, 0'08 broad ; thorax 012 long, 0'2 broad.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

9. Acanthocorys fur cata, n. sp.

Cephalis large, subspherical, spiny, with irregular, roundish pores. Thorax flatly conical, thorny,
with irregular, polygonal pores, decreasing in size towards the mouth, and with nine straight
divergent ribs, which at the peristome are forked and prolonged into eighteen slender, very long,
bristle-shaped feet.

Dimensions. — Cephalis 0'045 diameter, thorax 0'07 long, 013 broad.

Habitat. — South Atlantic, Station 323, depth 1900 fathoms.

Subgenus 3. Acanthocorythium, Haeckel.

Definition. — Thorax with a variable number (ten to twenty or more) radial ribs,
prolonged into free terminal feet.

10. Acanthocorys dodecaster, n. sp.

Cephalis small, subspherical, with small circular pores and a large conical horn of twice the
length, and some accessory spines. Thorax thorny, flatly campanulate, with twelve stout curved ribs,
which at the peristome are prolonged into twelve slender, curved feet of twice the length ; four of
them are centrifugal prolongations of the four cortinar beams separating the four large meshes of the
collar septum ; eight other ribs are secondary, interpolated in pairs between the former. At the
base of the thorax are twelve large triangular holes between the ribs ; the other network is irregular,
with polygonal meshes.

Dimensions. — Cephalis 0'03 diameter, thorax 0'05 long, 012 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

11. Acanthocorys polyrjodia, n. sp.

Cephalis small, hemispherical, with small, roundish pores and divergent radial spines. Thorax
flatly conical, spiny, with twenty to twenty-four divergent, straight ribs, which in the proximal

REPORT ON THE RADIOLARIA. 1265

third are separated by the same number of large, triangular meshes, in the middle third connected
by irregular network, in the distal third free.

Dimensions. — Cephalis 0'02 long, O03 broad ; thorax 0'06 long, 015 broad.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

Genus 564. Arachnocorys,1 Haeckel, 1860, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 837.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) with numerous
radial ribs in the wall of the pyramidal thorax, prolonged into divergent terminal feet.
Network double, with an arachuoidal outer mantle around the inner lattice -shell.
Cephalis commonly with numerous horns.

The genus Arachnocorys has been derived from the preceding Acanthocorys, by
development of numerous external siliceous threads which connect the radial horns of
the cephalis with the secondary spines arising from the thoracic ribs. In this way
there becomes formed an outer arachnoidal framework, enveloping loosely, like a delicate
mantle, the inner primary lattice-shell.

Subgenus 1. Arachnocorallium, Haeckel.

Definition. — Thorax with six divergent ribs or radial beams (three primary or
perradial, alternating with three secondary or interradial).

1. Arachnocorys hexaptera, n. sp.

Arachnocorys circumtexta (juv. 1), K. Hertwig, 1879, Organism, d. Radiol., p. 79, Taf. viii.
fig. 2a.

Cephalis large, subspherical, with irregular, polygonal pores, and numerous bristle-shaped spines
twice the length ; on the centre of the top a single larger vertical horn. Thorax flatly conical, with
six strong and straight widely divergent ribs, which in the proximal half are separated by six large
holes, in the distal half connected by a broad ring of irregular network. From each rib arises a
perpendicular branch, and these branches are connected together, and with the spines of the cephalis,
by arachnoidal network.

Dimensions. — Cephalis 0'04 diameter, thorax 0'08 long, 0'24 broad.

Habitat. — Central Pacific, Station 266 ; Mediterranean, surface.

2. Arachnocorys discoides, n. sp.

Cephalis small, pyramidal, with irregular, roundish pores and numerous thin spines, on the top
a single larger vertical horn. Thorax very flat, nearly discoidal, with six strong and straight ribs,

1 Arachnocorys — helmet with a cobweb ; et^a^un, xo'ji/j.

(ZOOL. CHALL. EXP. — PAET XL. 1886.) Ef 159

1260 THE VOYAGE OF H.M.S. CHALLENGER.

which by communication of few larger and numerous smaller branches form an irregular network
with polygonal meshes. From each of the six ribs arise two or three larger, perpendicular branches
of half the length, and from the network numerous smaller spines. All these dorsal spines of the
shell are connected by a dense arachnoidal wicker-work.

Dimensions. — Cephalis 0'02 diameter, thorax 0'04 long, 0'3 broad.

Habitat. — Central Pacific, Station 271, surface.

Subgenus 2. Arachnocoronium, Haeckel.

Definition. — Thorax with nine divergent ribs or radial beams, three of which are
primary or perradial, the other six secondary or interradial. (Sometimes eight or ten
occur instead of the nine normal ribs.)

3. Arachnocorys circumtexta, Haeckel.

Arachnocorys circmntexta, Haeckel, 1862, Monogr. d. Radiol., p. 304, Taf. vi. figs. 9-11.
Arachnocorys circumtexta, R. Hertwig, 1879, Organism, d. Radio!., p. 78, Taf. viii. fig. 2.

Cephalis large, subspherical, with numerous roundish pores, and eight to ten slender, conical
horns twice the length. Thorax flatly conical, with nine strong, straight, widely divergent, conical
feet, each of which bears in the middle of its outer side a perpendicular ascending branch of half the
length. These branches and the horns of the cephalis are connected by very thin, parallel, arach-
noidal threads. Network of the thorax irregular, with nine larger triangular holes at the base.
Collar septum with numerous, irregular, roundish pores.

Dimensions. — Cephalis 0'04 to 0'05 diameter, thorax O08 to 012 long, 015 to 0'25 broad.

Habitat. — Mediterranean (Messina) ; Atlantic, Stations 347 to 354, surface.

4. Arachnocorys enneaptera, n. sp.

Cephalis large, campanulate, with irregular, polygonal pores, two larger stout pyramidal and
numerous slender, bristle- shaped horns. Thorax of the same structure as in the preceding species,
only the nine basal holes are of twice the size ; the lower network denser (as in Clathrocanium
diadema, PL 64, fig. 2). Collar septum with numerous, irregular, roundish pores.

Dimensions. — Cephalis 005 diameter, thorax 012 long, 0'22 broad.

Habitat. — Tropical Atlantic, Station 338, surface.

5. Arachnocorys araneosa, n. sp. (PL 56, fig. 11).

Cephalis large, subspherical, with circular, subregular, hexagonally framed pores, and twenty to
thirty slender, cylindrical, straight radial spines. Thorax flatly conical, nearly of the same shape as
in the two preceding species, but with nine longer ribs, and more irregular, broader network between
them. From the middle of each rib arises, nearly horizontally, a strong branch, which is directed

REPORT ON THE RADIOLARIA. 1267

outwards. These branches are connected with the spines of the cephalis as well as with the distal
half of the ribs, by dense and delicate arachnoidal network, composed of parallel, very thin, siliceous
threads (in fig. 11 only partially represented). Collar septum with numerous irregular, roundish
pores.

Dimensions. — Cephalis 0'04 diameter, thorax O'l long, 0'2 broad.

Habitat. — Central Pacific, Statioto 270 to 274, surface.

6. Arachnocorys arachnodiscus, n. sp.

Cephalis small, campanulate, conical, with a single very large conical central horn, and numerous
smaller accessory spines. Thorax in form and structure similar to that of the three preceding
species, but much flatter, being nearly diseoidal. The meshes of the network are smaller and more
numerous, irregularly polygonal, and the nine basal holes little larger. Collar septum with four large
meshes (as in PI. 60, fig. 6).

Dimensions. — Cephalis 0'25 long, 0'3 broad ; thorax 0-04 long, 0'24 broad.

Habitat. — North Pacific, Station 248, surface.

7. Arachnocorys trifida, n. sp.

Cephalis large, campanulate, with irregular, roundish pores and numerous ramified spines ; in the
centre of the top a larger pyramidal oblique horn of twice the length. Thorax cap-shaped, flatly
vaulted, with nine strong convex ribs, prolonged into slender free feet. Three of these nine ribs are
the centrifugal prolongations of the three cortinar bars (united in the centre of the collar stricture,
separating its three large cortinar meshes); the other six are diverging lateral branches of the former,
arising in pairs at both sides of its base. All nine ribs are connected by delicate arachnoidal net-
work with irregular polygonal meshes. From its surface arise thin bristles, and from the base of each
main rib a stout, perpendicular branch. All these dorsal spines are connected by irregular,
arachnoidal wicker-work, covering thorax and cephalis. (A remarkable primitive species ?)

Dimensions. — Cephalis 0'05 long, 0'06 broad ; thorax O07 long, 018 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Subgenus 3. Arachnocorythium, Haeckel.

Definition. — Thorax with a variable number of radial ribs (twelve to twenty or
more), prolonged into free terminal feet.

8. Arachnocorys polyptera, n. sp.

Cephalis large, subspherical, with irregular, roundish pores and numerous radial spines. Thorax
flatly conical, with numerous radial ribs (twenty to thirty), which are in the distal half free, in the
proximal half connected by delicate arachnoidal wicker-work, with polygonal, irregular meshes.
From its dorsal face arise numerous radial spines, which are connected together, and with the
cephalic spines, by very thin and numerous threads, parallel between every two spines. Similar to

1268 THE VOYAGE OF H.M.S. CHALLENGER,

Araclinocorys araneosa (PL 56, fig. 11), but differing in the structure of the cephalis, and in the greater
number of the ribs and spines.

Dimensions. — Cephalis O04 diameter, thorax 012 long, 0'24 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

Genus 565. Anthocyrtoma,1 n. gen.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) without thoracic
ribs, with six terminal feet around the mouth. Cephalis free, with an apical horn.

The genus Anthocyrtoma and the four following genera form together the peculiar
group of Carpocanida, comprising all those Sethophormida in which the original thoracic
ribs are lost, and only the terminal feet remain. Anthocyrtoma is the simplest form
of this group, possessing only six terminal feet, three primary perradial, and three alter-
nating, secondary, interradial. It may be directly derived either from Lychnocanium,
by interpolation of three interradial feet, or from Hexaspyris by loss of the sagittal
ring.

1. Anthocyrtoma serrulata, Haeckel.

Anthocyrtis serrulata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. vi.

fig. 7.

Shell pear-shaped, rough, with obliterated collar stricture. Length of the two joints =1:4,
breadth = 1:3. Cephalis ovate, with very small pores, and a stout conical horn of the same
length. Abdomen inflated, truncate, with larger, regular, circular pores, twice as broad as the con-
stricted mouth. Six feet vertical, parallel, serrate, all of the same size, about as long as the
cephalis.

Dimensions. — Cephalis 0-06 long, 0'05 broad ; thorax 0'2 long, 017 broad.

Habitat — Fossil in Barbados.

2. Anthocyrtoma alterna, n. sp.

Shell pear-shaped, smooth, with distinct collar stricture. Length of the two joints = 1:5,
breadth =1:6. Cephalis hemispherical, with a slender conical horn of twice the length.
Abdomen inflated, subglobular, with regular, circular, hexagonally framed pores, three times as broad
as the narrow, constricted mouth. Six feet conical, smooth, somewhat divergent, alternating, of
different sizes ; the three larger (perradial) half as long as the shell, and twice as long as the three
smaller (interradial). (Similar to Anthocyrtis ventricosa.)

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 015 long, 018 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

1 A nthocyrtoma= Flower-arch ; 0.1/60;,

REPORT ON THE RADIOLARIA. 1269

Genus 566. Anthocyrtis,1 Ehrenberg, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, 1847, p. 54.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) without
thoracic ribs, with nine terminal feet around the mouth. Cephalis free, with an apical
horn.

The genus Anthocyrtis (in the original definition of Ehrenberg) contained all Dicyrtida
without thoracic ribs, with terminal feet. We here restrict the definition to those Setho-
phormida in which the number of free terminal feet is constantly nine (three primary
perradial and three alternate pairs of secondary interradial feet). Anthocyrtis may be
derived either directly from Patagospyris by loss of the sagittal ring, or from Lychno-
canium by interpolation of three secondary feet.

Subgenus 1. Anthocyrtella, Haeckel.

Definition. — Feet of the peristome-corona divergent, their basal distance less than
their terminal distance.

1. Anthocyrtis mespilus, Ehrenberg.

Anthocyrtis mespilus, Ehrenberg, 1854, Taf. xxxvi. fig. 13 ; Abhandl. d. k. Akad. d. Wiss.
Berlin, 1875, p. 66, Taf. vi. fig. 4 (not 5).

Shell smooth, with distinct collar stricture. Length of the two joints = 1 : 5, breadth = 2:6.
Cephalis hemispherical, with a stout pyramidal horn of twice the length. Thorax nearly hemi-
spherical, with regular, circular, quincuncial pores. Mouth scarcely constricted, with nine divergent,
triangular, lamellar feet, about as long as the thorax.

Dimensions. — Cephalis 0'012 long, O02 broad ; thorax 005 long, 0'06 broad.

Habitat. — Fossil in Barbados.

2. Anthocyrtis fur cata, Ehrenberg.

Anthocyrtis furcata, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 64, Taf. vi.
fig. 2.

Shell smooth, with deep collar stricture. Length of the two joints = l:5, breadth = 2:6.
Cephalis hemispherical, with a short pyramidal horn of half the length. Thorax hemispherical,
with large, irregular, roundish pores. Mouth scarcely constricted, with nine divergent, curved,
slender feet, which are about as long as the shell, and forked at the distal end.

Dimensions. — Cephalis O'Ol long, 0'02 broad ; thorax 0'05 long, 0'06 broad.

Habitat. — Fossil in Barbados.

1 Anthocyrtis = Flower-basket ; eLv6o(, >

1270 THE VOYAGE OF H.M.S. CHALLENGER.

3. Anthocyrtis butomus, n. sp.

Shell thorny, with obliterated collar stricture. Length of the two joints = 2:6, breadth = 2:7.
Cephalis ovate, with very small and scarce pores, and a conical horn of the same length. Thorax
inflated, pear-shaped, with regular, circular, quincuncial pores. Mouth about half as broad, con-
stricted, with nine divergent, broad, nearly square, lamellar feet, half as long as the thorax (similar
to Anthocyrtis serrulata, Ehrenberg, loc. cit., Taf. vi. fig. 7).

Dimensions. — Cephalis 0'05 long, 0'04 broad; thorax 0'12 long, 0'14 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Anthocyrtis ventricosa, Ehrenberg.

Anthocyrtis ventricosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. viii.
fig. 1.

Shell thorny, with obliterated collar stricture. Length of the two joints = 1:7, breadth =
2 : 7. Cephalis hemispherical, hyaline, without pores, with a slender, conical horn, of about the
same length. Thorax inflated, pear-shaped or subspherical, with regular, circular, quincuncial pores.
Mouth only one-third as broad, much constricted, with nine divergent, slender, conical feet, about
one-fifth as long as the diameter of the shell (partly broken off in Ehrenberg's figure).

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'14 long, 0'14 broad.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms ; also fossil in Barbados.

Subgenus 2. Anthocyrtissa, Haeckel.

Definition. — Feet of the peristome-corona parallel, vertical ; their basal and terminal
distances equal.

5. Anthocyrtis ophirensis, Ehrenberg.

Anthocijrtis ophirensis, Ehrenberg, 1872, Abhandl. d. k, Akad. d. Wiss. Berlin, p. 285, Tnf. ix.
fig. 13.

Shell smooth, with slight collar stricture. Length of the two joints = 2:4, breadth=l:5.
Cephalis ovate, with irregular, roundish pores, and a pyramidal, excentric, vertical horn of the same
length. Thorax campanulate, with delicate network of large, regular, hexagonal pores. Mouth
scarcely constricted, with nine parallel, vertical, conical feet, about as long as the cephalis. (In the
specimen figured by Ehrenberg only seven feet are represented, two being broken off; two other
specimens of this species, captured by Eabbe, exhibited nine regularly disposed feet.)

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 0-08 long, O'l broad.

Habitat. — Indian Ocean, Zanzibar (Pullen) ; Madagascar (Eabbe), surface.

REPORT ON THE RADIOLARIA. 1271

(j. Anthocyrtis lauranthus, n. sp.

Shell smooth, with slight collar stricture. Length of the two joints = 1:3, breadth = 1:4.
Cephalis ovate, with large, roundish pores, and a conical horn of twice the length. Thorax inflated,
campanulate, with regular, circular, hexagonally framed pores. Mouth two-thirds as broad, little
constricted, with nine parallel, vertical, broad, lamellar, triangular feet, half as long as the cephalis.

Dimensions. — Cephalis 0'04 long, 0'03 broad; thorax 01 long, 012 broad.

Habitat. — Central Pacific, Station 266 to 270,' depth 2550 to 2925 fathoms.

7. Anthocyrtis grossularia, Ehrenberg.

Anthocyrtis grossularia, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 64, Taf. vi.
fig. 6.

Shell spiny, with deep collar stricture. Length of the two joints = 1:5, breadth = 1:4.
Cephalis subspherical, thorny, with a conical horn of the same length. Thorax ovate, spiny, with
numerous densely-crowded, subregular, circular pores. Mouth about half as broad, constricted,
with nine parallel, vertical, slender, conical feet, about as long as the cephalis.

Dimensions. — Cephalis 0'04 long, 0-05 broad ; thorax 0'2 long, 018 broad.

Habitat. — Fossil in Barbados.

8. Anthocyrtis subglobosa, n. sp.

Shell spiny, with deep collar stricture. Length of the two joints = 1:7, breadth = 1:7.
Cephalis subspherical, with a conical horn twice the length. Thorax nearly spherical, with
small and very numerous, regular, circular pores. Mouth only one-third as broad, constricted, with
nine parallel, vertical, square, lamellar feet, about twice as long as the cephalis.

Dimensions. — Cephalis 0'03 long, 0'035 broad; thorax 0'2 long, 0'2 broad.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

Subgenus 3. Anthocyrtura, Haeckel.

Definition. — Feet of the peristome-corona convergent, their basal distance greater
than their terminal distance.

9. Anthocyrtis enneaphylla, n. sp.

Shell smooth, with sharp collar stricture. Length of the two joints = 1 : 6, breadth = 1 : 5.
Cephalis subspherical, with a conical horn twice the length, nearly hyaline, with very small
and scarce pores. Thorax nearly spherical, with regular, circular, quincuncial pores. Mouth only

1272 THE VOYAGE OF H.M.S. CHALLENGEE.

half as broad, with nine broad, triangular feet, twice as long as the cephalis, and curved inwards,
convergent towards the main axis.

Dimensions. — Cephalis 0'02 long, 0'025 broad ; thorax Oil long, 012 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

10. Anthocyrtis ovata, n. sp. (PL 62, fig. 13).

Shell smooth, with slight collar stricture. Length of the two joints = 1:5, breadth = 1:3.
Cephalis ovate, with numerous small pores, and an excentric conical horn of the same length.
Thorax ovate, with regular, circular, quincuncial pores. Mouth nearly of the same breadth,
scarcely constricted, with nine triangular, widely-separated feet, about as long as the cephalis, and
convergent towards the main axis.

Dimensions. — Cephalis 0'035 long, 0'03 broad ; thorax 015 long, 01 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 567. Anthocyrtium,1 n. gen.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) without
thoracic ribs, with numerous terminal feet around the mouth (twelve to fifteen or
more). Cephalis free, with an apical horn.

The genus Anthocyrtium has been derived from the two preceding genera by further
multiplication of the terminal feet, the number of which is at least twelve to fifteen,
often twenty or more. It may be that some species have arisen directly from Pata-
gospyris by loss of the sagittal ring.

Subgenus 1. Anthocyrtarium, Haeckel.

Definition. — Feet of the peristome-corona divergent, their basal distance less than
their terminal distance.

1. Anthocyrtium chrysanthemum, n. sp. (PL 62, fig. 14).

Shell smooth, with distinct collar stricture. Length of the two joints = 3:7, breadth = 4:9.
Cephalis hemispherical, with small, circular pores, and a large, straight, cylindro-conical horn, about
as long as the shell. Thorax campanulate, hemispherical, with six to eight transverse rows of
squarish pores, increasing in size downwards. Mouth little constricted, with twelve to fifteen
divergent, curved, slender feet, about as long as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'07 long, 0'09 broad.

Habitat. — Central Pacific, Station 270 to 274, depth 2350 to 2925 fathoms.

1 Anthocyrtium- Flower-basket; &v6oi, xiifriou.

REPORT ON THE RADIOLARIA. 1273

2. Anthocyrtium centaurea, Haeckel.

Anthocyrtis mespilus, var. major, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66,
Taf. vL fig. 5.

Shell smooth, with sharp collar stricture. Length of the two joints = 2:6, breadth = 3:7.
Cephalis hemispherical, with irregular, roundish pores, and a very large pyramidal horn, longer than
the shell, with contorted edges. Thorax hemispherical, with six to eight transverse rows of regular,
circular pores of equal size. Mouth little constricted, with fifteen to twenty divergent, curved,
slender feet, about as long as the shell.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'06 long, 0'07 broad.

Habitat. — Fossil in Barbados.

3. Anthocyrtium anthemis, n. sp.

Shell papillate, with obliterated collar stricture. Length of the two joints = 1:3, breadth = 1:3.
Cephalis hemispherical, with very small and scarce pores, and a conical horn of the same length.
Thorax conical, as long as broad, with conical papillae, and eight to ten transverse rows of roundish
pores, gradually increasing in size downwards. Mouth scarcely constricted, with fifteen to twenty
divergent, straight, conical feet, half as long as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'09 long, O09 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Anthocyrtium collar e, Haeckel.
Anthocyrtis collaris, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 64, Taf. vi. fig. 8.

Shell rough, conical, with obliterated collar stricture. Length of the two joints = 3:5,
breadth = 4:7. Cephalis conical, with a pyramidal horn of the same length, and with two
transverse rows of rather oblong, narrow pores. Thorax truncate, conical, in the lower part thorny,
with six to eight transverse rows of regular, circular pores, increasing in size downwards.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'05 long, 0'07 broad.

Habitat. — Fossil in Barbados.

5. Anthocyrtium adonis, n. sp. (PI. 62 fig. 20).

Shell rough, with sharp collar stricture. Length of the two joints = 3 : 10, breadth =4 : 12.
Cephalis subspherical, with very small circular pores, and a very long, straight cylindrical, horn, twice
to three times as long as the shell. Thorax inflated, ovate, or subspherical, with small regular, circular,
hexagonally-framed pores. Mouth strongly constricted, half as broad as the thorax, with fifteen to

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 160

1274 THE VOYAGE OF H.M.S. CHALLENGER.

twenty divergent, broad, lamellar, rectangular feet, as long as the thorax, and so densely placed
that their margins come in contact with one another.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 01 long, 012 broad.

Habitat. — Central Pacific, Station 263 to 268, depth 2650 to 3000 fathoms.

6. Anthocyrtium anemone, n. sp.

Shell spiny, with sharp collar stricture. Length of the two joints = 1:5, breadth =1:4.
Cephalis subspherical, with a conical horn of half the length, hyaline, without pores. Thorax
spiny, pear-shaped, inflated, with small and numerous, regular, circular pores. Mouth constricted,
half as broad as the thorax, with twelve to fifteen divergent, slender, conical, denticulate feet, half
as long as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 014 long, 012 broad.

Habitat. — Tropical Atlantic, Station, 347, depth 2250 fathoms ; also fossil in Barbados.

Subgenus 2. Anthocyrtonium, Haeckel.

Definition. — Feet of the peristome-corona parallel, vertical ; their basal and apical
distances equal.

7. Anthocyrtium campanula, n. sp. (PI. 62, fig. 17).

Shell smooth, with deep collar stricture. Length of the two joints = 1:3, breadth = 1:3.
Cephalis spherical, with a conical horn of the same length. Thorax campanulate, thin-walled, with
delicate network of regular, hexagonal pores and thin bars. Mouth little constricted, with twenty
to twenty-four parallel, vertical, lanceolate feet, about as long as the cephalis.

Dimensions. — Cephalis 0'03 diameter, thorax 0'09 long, 01 broad.

Habitat. — South Pacific, Station 302, depth 1450 fathoms.

8. Anthocyrtium, reticulatum, Haeckel.

Tltyrsocyrtis reticulata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii.
fig. 10.

Shell rough, with sharp collar stricture. Length of the two joints = 1:2, breadth = 1:3.
Cephalis hemispherical, with a prismatic, denticulate horn of the same length, and small, irregular
pores. Thorax campanulate, thorny, thin-walled, with delicate network of irregular, polygonal pores.
Mouth little constricted, with twelve (or more) small, parallel, vertical, triangular feet, shorter than

the cephalis.

Dimensions. — Cephalis 0'015 long, 0'02 broad ; thorax 0'04 long, 0'06 broad.
Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1275

9. Anthocyrtium leptostylum, Haeckel.

Anthocyrtis leptostyla, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 64, Taf. vi.
fig. 1.

Shell thorny, with slight collar stricture. Length of the two joints = 1 : 5, breadth = 2 : 4.
Cephalis hemispherical, with small, scarce pores and a slender conical horn of the same length.
Thorax spiny, with regular, circular, quincuncial pores. Mouth constricted, half as broad, with
twelve to eighteen slender, parallel, vertical feet, about as long as the cephalis.

Dimensions. — Cephalis 0'02 long, 004 broad ; thorax 01 long, 0'08 broad.

Habitat. — Central Pacific, Stations 266 to 270, depth 2550 to 2925 fathoms ; also fossil in
Barbados.

10. Anthocyrtium hispidum, Haeckel.

Anthocyrtis hispida, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 64, Taf. viii.

fig. 2.
Anthocyrtis hispida, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 540, Taf. xxxiii.

fig. 30.

Shell thorny, with sharp collar stricture. Length of the two joints = 1:4, breadth = 2:5.
Cephalis hemispherical, hyaline, with few very small pores, or without any ; with a stout conical
horn of twice the length. Thorax spiny, with regular, circular, hexagonally-framed pores (half as
broad as the bars between them). Mouth wide open, scarcely constricted, with twelve to fifteen
parallel, vertical, broad, lamellar, rectangular feet, reaching nearly the length of the thorax.

Dimensions. — Cephalis 0'02 to 0'03 long, 0'03 to 0"05 broad ; thorax 0'07 to 0'09 long, 01 to
012 broad.

Habitat. — Central Pacific, Stations 263 to 265, depth 2650 to 3000 fathoms ; also fossil in
Barbados.

11. Anthocyrtium turris, n. sp.

Shell thorny, very similar to Calocydas turris, Ehrenberg (1875, loc. tit., Taf. xviii. fig. 7), but
without fenestrated abdomen. Collar stricture deep. Length of the two joints = 1 : 3,
breadth = 1 : 3. Cephalis subspherical, hyaline, without pores, with a stout conical horn of
twice the length. Thorax nearly spherical, spiny, with regular, circular, quincuiicial pores.
Mouth little constricted, with fifteen to twenty parallel, vertical, broad, lamellar, rectangular
feet, about as long as the thorax.

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax 01 long, 01 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

1276 THE VOYAGE OF H.M.S. CHALLENGER.

12. Anthocyrtium doronicum, n. sp. (PL 62, fig. 18).

Shell rough, with sharp collar stricture. Length of the two joints = 1:5, breadth = 1:3.
Cephalis hemispherical, with small, circular pores and a stout conical horn of twice the length.
Thorax campanulate, subcylindrical, with regular, circular, quincuncial pores, three to four times as
broad as the bars. Mouth scarcely constricted, with twenty-four to thirty vertical, nearly
parallel, little curved feet, which are about half as long as the shell, broad, lamellar, rectangular,
and in close contact with their edges.

Dimensions — Cephalis 0'025 long, 0'035 broad ; thorax 012 long, 01 broad.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

Subgenus 3. Anthocyrturium, Haeckel.

Definition. — Feet of the peristome-corona convergent, their basal distance greater
than their apical distance.

13. Anthocyrtium pyrum, n. sp. (PL 62, fig. 12).

Shell smooth, with obliterated collar stricture. Length of the two joints = 2:7, breadth = 3:8.
Cephalis hemispherical, with a small, bristle-shaped horn of half the length. Thorax inflated,
subglobose, with regular, circular, quincuncial pores and thin bars. Mouth constricted, only half
as broad, with fifteen to twenty small, triangular, convergent feet, shorter than the cephalis. (In
another specimen the feet were twice as long, stronger and more convergent, than in the one
figured.)

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'07 long, O'S broad.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

1 4. Anthocyrtium setosum, Haeckel.

Anthocyrtis setosa, Haeckel, 1862, Monogr. d. Eadiol., p. 311.
1 Lithopera setosa, Ehrenberg, 1854, Mikrogeol., Taf. xxxv. B., B. iv. fig. 23.

Shell spiny, with sharp collar stricture. Length of the two joints = 1:2, breadth = 1:3.
Cephalis hemispherical, with a conical horn of the same length and some accessory spines.
Thorax campanulate, with subregular, circular pores. Mouth little constricted, with twenty to
thirty small, triangular, convergent feet, about as long as the cephalis. (In Ehrenberg's incomplete
figure they are mostly broken off.)

Dimensions.— Cephalis 0'02 long, 0'02 broad ; thorax 0-04 long, 0'06 broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

REPORT ON THE RADIOLARIA. 1277

15. Anthocyrtium ehrenbergii, Haeckel.

Anthocyrtis ehreribergii, Stbhr, 1880, Palaeontogr., vol. xxvi. p. 100, Taf. iii. fig. 21, a, b.

Shell smooth, with obliterated collar stricture. Length of the two joints = 3 : 10.
breadth = 2:8. Cephalis subcylindrical, with an excentric, stout, pyramidal horn of the same
length. Thorax bottle-shaped, with small, regular, circular pores of equal size. Mouth little
constricted, with twenty to thirty small, triangular, convergent feet, about half as long as the
cephalis.

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 01 long, 0'08 broad.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte), Stb'hr.

16. Anthocyrtium zanguebaricum, Haeckel.

Anthocyrtis zanguebarica, Ehrenberg, 1872, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 285,
Taf. ix. fig. 12.

Shell smooth, with slight collar stricture. Length of the two joints = 3 : 10, breadth = 2 : 7.
Cephalis subspherical, with an excentric conical horn of the same length. Thorax slender, ovate
or bottle-shaped, with irregular, roundish pores increasing in size downwards. Mouth little con-
stricted, with twelve to fifteen small, triangular, convergent feet, about half as long as the cephalis.

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 01 long, 0'07 broad.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms, Pullen.

17. Anthocyrtium fans, Haeckel.

Antlwcyrtis Jicux, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 64, Taf. vi. fig. 3.

Shell rough, with obliterated collar stricture. Length of the two joints = 2 : 12, breadth = 3 : 10.
Cephalis conical, with a large, cylindrical horn, pyramidal at the base, about as long as the thorax.
Thorax subovate, truncate, papillate, with small, regular, circular, quincuncial pores of the same
breadth as the bars. Mouth constricted, two-thirds as broad as the thorax, with fifteen to twenty
strongly convergent, lamellar, rectangular or sword-shaped feet, nearly as long as the thorax.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 012 long, 01 broad.

Habitat. — Fossil in Barbados.

18. Anthocyrtium flosculus, n. sp. (PL 62, fig. 19).

Antliocyrtis flosculus, Haeckel, 1881, Prodromus et Atlas, pi. Ixii fig. 19.

Shell ribbed, with distinct collar stricture. Length of the two joints =1 : 4, breadth = 2 : 4.
Cephalis hemispherical, with small, circular pores and a large cylindrical horn, twice as long as
the thorax and half as broad at the base as the cephalis. Thorax subovate, truncate, with twenty-
four to thirty longitudinal ribs and alternating rows of circular pores. Mouth constricted, two-thirds

1278 THE VOYAGE OF H.M.S. CHALLENGER.

as broad as the thorax, with twenty-four to thirty slender, convergent feet, which are as long as
the entire shell, with their edges in close contact and their distal euds pointed.

Dimensions. — Cephalis O03 long, 0'05 broad ; thorax 012 long, 012 broad.

Habitat. —Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

Genus 568. Anthocyrtidium,1 Haeckel, 1881, Prodromus, p. 431.

Definition. — Sethophormida, (vel Dicyrtida multiradiata aperta) without
thoracic ribs, with numerous (twelve to fifteen or more) subterminal feet, which are
separated from the constricted mouth by a ring of lattice-work. Cephalis free, with
an apical horn.

The genus Anthocyrtidium has been derived from the preceding Anthocyrtium by
further growth and constriction of the peristome, which becomes separated from the
subterminal corona of feet by a more or less broad ring of lattice-work.

1. Anthocyrtidium cineraria, n. sp. (PI. 62, fig. 16).

Shell campanulate, smooth, with obliterated collar stricture. Length of the two joints = 5:11,
breadth = 3 : 13. Cephalis subcylindrical-ovate, with a conical straight horn of half the length.
Thorax hemispherical, inflated, nearly twice as broad as the constricted mouth. Pores subregular,
circular, double-contoured. Above the mouth, separated from it by two rows of pores, a corona
of twelve to fifteen short conical feet, which are directed downwards, slightly curved, and as long
as the cephalic horn.

Dimensions. — Cephalis 0'05 long, 0'03 broad ; thorax Oil long, 013 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Anthocyrtidium 'ligularia, n. sp. (PI. 62, fig. 15).

Shell campanulate, rough, with distinct collar stricture. Length of the two joints = 1:4,
breadth = 2:6. Cephalis hemispherical, with a slender, conical, slightly curved horn, about as long
as the shell. Thorax hemispherical, three times as broad as the cephalis, nearly twice as broad as
the constricted mouth, which is prolonged into a prominent smooth ring. Above the mouth,
separated from it by one row of pores, a corona of twelve to fifteen slender linear feet, ,which are
slightly curved, divergent, and emarginate at the truncated distal end.

Dimensions. — Cephalis 0'015.1ong, 0'03 broad; thorax 0'06 long, 0:09 broad.
Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

1 Anthocyrtidium ='Small flower-basket ; Autos, wfriJiw.

REPORT ON THE RADIOLARIA. 1279

3. Anthocyrtidium matricaria, n. sp.

Shell campanulate, rough, very similar to the preceding species, but differing in the straight,
large, pyramidal horn of the cephalis (as long as the shell), and in the longer feet, which are twelve
to fifteen in number, little curved at the distal end, pointed, and about as long as the shell. Length
of the two joints = 2:6, breadth = 3:8. Differs from the similar Anthocyrtium eentaurea, Ehrenberg
(1875, loc. cit, Taf. vi. fig. 5), mainly in the prominent ring of the peristome.

Dimensions. — Cephalis, 0'02 long, 0'03 broad ; thorax 0'06 long, 0'08 broad.

Habitat. — Fossil in Barbados.

Genus 569. Carpocanium,1 Ehrenberg, 1847, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 54.

Definition. — S ethophormida (vel Dicyrtida multiradiata aperta) without
thoracic ribs, with numerous terminal feet around the mouth (six to twelve or more).
Cephalis hidden in the thorax, without apical horn.

The genus Carpocanium, very common, and rich in numerous living and fossil
species, was formerly placed by me among the true Monocyrtida, since an external
constriction is not visible (Monogr., 1862, p. 290). Afterwards (in 1879) Eichard Hertwig
demonstrated that the cavity of the ovate shell, externally simple, is divided by an
internal transverse septum into two joints, the upper of which is the flat rudimentary
cephalis (Organism, d. Eadiol., p. 79 ; compare also Biitschli, 1882, loc. cit., p. 535).
Indeed this septum, with four central crossed cortinar beams, is a true collar septum,
and Carpocanium has been derived from Anthocyrtis or Desmospyris by reduction of
the cephalis, which is very flat and perfectly hidden in the uppermost part of the
thorax. The apical horn is lost. If the internal septum were to become lost, the genus
would pass over into Carpocanistrum.

Subgenus 1. Carpocanarium, Haeckel.

Definition. — Peristome-corona composed of six feet (three primary perradial alter-
nating with three secondary interradial).

1. Carpocanium caly codes, Stohr.

Carpocanium call/codes, Stohr, 1880, Palaeontogr., vol. xxvi. p. 96, Taf. iii. fig. 8.

Shell urceolate, smooth, nearly twice as long as broad, with hemispherical vaulted cephalis.
Length of the two joints = 3 : 16, breadth =5 : 10. Pores regular, circular, as broad as the bars,

1 Carpoeanium — Fruit-basket ; xacpirvs. natitov.

1280 THE VOYAGE OF H.M.S. CHALLENGER.

quincuncially disposed in about five longitudinal series at each side. Mouth constricted, half as
broad as the thorax. Peristome with six vertical, equilateral, triangular feet.

Dimensions. — Cephalis 0'015 long, 0'025 broad ; thorax O'OS long, 0'05 broad.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).

2. Carpocanium setosum, Haeckel.

Halicalyptra setosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 160, Taf. ii.
fig. 12.

Shell ovate, truncate at the mouth, thorny, exactly as long as broad. Length of the two
joints = 1:8, breadth = 3:9. Cephalis hidden, with very small pores. Thorax inflated, with
regular, circular pores, twice as broad as the bars, in about ten longitudinal series at each
side. Mouth constricted, half as broad as the thorax. Peristome with six vertical, parallel,
broad, lamellar, rectangular feet, separated by equal intervals, half as long as the shell.

Dimensions. — Cephalis O'Ol long, O'OS broad; thorax O'OS long, OD9 broad.

Habitat. — Fossil in Barbados.

3. Carpocanium laeve, Ehrenberg.

Carpocanium laeve, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287.

Shell subspherical, smooth, equal in length and breadth, with little vaulted, cap-shaped cephalis.
Length of the two joints = 1 : 6, breadth =4 : 7. Pores regular, circular, twice as broad as the
bars, in nine longitudinal rows. Mouth constricted, only one-third as broad as the thorax.
Peristome with six strong conical feet, which are slightly curved and convergent.

Dimensions. — Cephalis O'Ol long, 0'04 broad ; thorax 0-Q6 long, 0'07 broad.

Habitat. — Mediterranean (Greece) ; Tropical Atlantic, Station 348, depth 2450 fathoms.

4. Carpocanium lanceolatum, n. sp.

Shell subspherical, thorny, with perfectly hidden cephalis. Length of the two joints = 1:3,
breadth = 1:3. Pores regular, circular, hexagonally framed, half as broad as the bars, in about
sixteen longitudinal rows at each side. Mouth constricted, half as broad as the thorax. Peristome
with six large lanceolate, vertical, lamellar feet, half as long as the shell.

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax 0'09 long, 0'09 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

Subgenus 2. Carpocanidium, Haeckel.

Definition. — Peristome-corona composed of nine feet (three primary perradial and six
secondary interradial).

REPORT ON THE RADIOLARIA. 1281

5. Carpocanium diadema, Haeckel.

Carpofanimn diadema, Haeckel, 1862, Monogr. d. Radiol, p. 290, Taf. v. fig. 1.
Carpocanium diadema, R. Hertwig, 1879, Organism, d. Radiol., p. 79, Taf. viii. figs. 7, 7 a,

8, 8a, 86.

Shell ovate, with little vaulted cephalis. Length of the two joints =1 : 8, breadth = 3 : 6.
Pores regular, circular, in about twelve longitudinal rows, twice as broad as the bars. Mouth
constricted, half as broad as the thorax. Peristome with nine vertical, equilateral, triangular feet.

Dimensions. — Cephalis O'Ol long, 0'03 broad ; thorax 0'08 long, 006 broad.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific ; many stations, surface.

6. Carpocanium cylindricum, n. sp.

Shell cylindrical, with hemispherical, flatly vaulted cephalis. Length of the two joints = 1:4,
breadth = 3:3. Pores regular, circular, double-contoured, as broad as the bars, in about fifteen
longitudinal 'series. Mouth constricted, two-thirds as broad as the thorax. Peristome with nine
vertical, slender, triangular, pointed feet.

Dimensions. — Cephalis 0'02 long, O'OG broad ; thorax O08 long, 0'06 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

7. Carpocanium enneaphyllum, n. sp.

Shell slenderly ovate, at the mouth truncate, thorny, with hemispherical, vaulted cephalis. Length
of the two joints = 1:6, breadth = 2:4. Pores regular, circular, hexagonally framed, as broad as the
bars, in about thirteen longitudinal rows. Mouth constricted, about two-thirds as broad as the
thorax. Peristome with nine broad, lamellar, vertical, nearly square feet, half as long as the shell,
with small intervals.

Dimensions. — Cephalis 0'02 long, 0'04 broad ; thorax 012 long, 0'09 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

i

8. Carpocanium solitarium, Ehrenberg.

Carpocanium solitarium, Ehrenberg, 1854, Mifcrogeol., Taf. xxii. fig. 28.

Lithocampe solitaria, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 65.

Shell slenderly ovate, twice as long as broad, with hidden spherical cephalis, completely enclosed
in the summit of the thorax. Length of the two joints = 1:6, breadth = 1:4. Pores small, regular,
circular, as broad as the bars, in about eleven longitudinal rows. Mouth gradually constricted, half
as broad as the thorax. Peristome with nine ovate blunt feet, which are as long as the cephalis,
little curved and convergent.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'12 long, 0'07 broad.

Habitat. — Fossil in Tertiary rocks of Sicily (Caltanisetta).

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 161

1282 THE VOYAGE OF H.M.S. CHALLENGER.

9. Carpocanium gemmula, n. sp.

Shell subspherical, smooth, equal in length and breadth, with hemispherical vaulted cephalis.
Length of the two joints = 2 : 7, breadth = 4 : 9. Pores small, regular, circular, twice as broad as the
bars, in about twenty longitudinal rows. Mouth strongly constricted, only one-fourth as broad as
the thorax. Peristome with nine conical feet, which are twice as long as the cephalis, curved, and
so convergent that their distal ends come nearly in contact.

Dimensions. — Cephalis 0'02 long, 0'04 broad ; thorax 0'07 long, 0'09 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

10. Carpocanium microdon, Ehrenberg.

Carpocanium microdon, Ehrenberg, 1858, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 30.

Shell broad, ovate, rough, with perfectly hidden cephalis. Length of the two joints = 2:9,
breadth = 4:7. Pores very small and scarce, smaller than the bars between them, irregularly
scattered. Mouth constricted, one-third as broad as the thorax. Peristome with nine short,
triangular, pointed, convergent feet.

Dimensions. — Cephalis 0'02 long. 0'04 broad ; thorax 0'09 long, 0'07 broad.

Habitat . — Mediterranean (Crete), Atlantic (Canary Islands), Station 354, surface.

Subgenus 3. Carpocanobium, Haeckel.
Definition. — Peristome-coroua composed of twelve or more feet.

11. Carpocanium trepanium, n. sp. (PL 52, fig. 18).

Shell subcylindrical, with flatly vaulted cephalis. Length of the two joints = 1:6, breadth = 3:4.
Pores regular, hexagonal, four to six times as broad as the bars. Mouth little constricted, two-
thirds as broad as the thorax. Peristome with eighteen to twenty-four large, slender, triangular,
vertical feet.

Dimensions. — Cephalis 0-02 long, 0'06 broad ; thorax 012 long, 0'08 broad.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

12. Carpocanium hexagonale, n. sp. (PI. 52, fig. 15).

Shell broadly ovate or subconical, with vaulted, cap-shaped cephalis. Length of the two joints =
2 : 7, breadth = 5 : 9. Thorax subglobular, truncate. Pores subregular, hexagonal, three to four
times as broad as the bars. Mouth constricted, two-thirds as broad as the thorax. Peristome with
twenty to twenty-five small, triangular, vertical feet.

Dimensions. — Cephalis 0'02 long, 0'05 broad ; thorax 0'07 long, 0'09 broad.

Habitat. — Tropical Atlantic, Station 347, surface.

REPORT ON THE RADIOLARIA. 1283

13. Carpocanium petalospyris, n. sp. (PL 52, fig. 19).

Shell subspherical, smooth, with perfectly hidden cephalis. Length of the two joints = 1:6,
breadth = 3:6. Pores regular, circular, hexagonally framed, twice as broad as the bars, in about
sixteen longitudinal rows. Mouth slightly constricted, little narrower than the thorax. Peristome
with twenty to twenty-four vertical, broad, lamellar feet, which are nearly as long as the shell, at
the distal end truncate, and almost in contact at their edges.

Dimensions. — Cephalis 0'02 long, 005 broad ; thorax O'll long, 012 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

14. Carpocanium polypterum, Haeckel.

Cryptoprora polyptera, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. ix.

fig. 17.
Carpocanium macropterum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 302.

Shell campanulate-conical, smooth, with perfectly hidden cephalis. Length of the two joints =
1 : 6, breadth = 4:6. Pores regular, circular, twice as broad as the bars, in about sixteen longi-
tudinal rows. Mouth wide open, not constricted. Peristome with twenty to thirty vertical, slender,
conical feet, about as long as the shell.

Dimensions. — Cephalis O'Ol long, 0'04 broad ; thorax 0'06 long, 0'06 broad.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms (Pullen).

15. Carpocanium palmipes, n. sp.

Shell ovate, very thick-walled, smooth. Lower half of the subspherical cephalis hidden in the
summit of the thorax, upper half free, with few small pores. Length of the two joints = 3 : 10,
breadth =3 : 10. Thorax foveolate, with oblong dimples, each of which encloses a small, circular,
double-contoured pore, half as broad as the bars. Mouth little constricted, nearly as broad as the
thorax. Peristome prolonged into a solid, cylindrical tiibe, nearly as long and as broad as the
shell ; the upper half of the tube is solid, the lower divided into from twelve to fifteen vertical,
lamellar, pointed feet.

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax O'l long, O'l broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

16. Carpocanium peristomium, n. sp. (PL 52, figs. 16, 17).

Shell ovate, smooth, with perfectly hidden, flat cephalis (fig. 17). Length of the two
joints = 2 : 10, breadth = 5 : 9. Pores small and very numerous, regular, circular, as broad as the
bars, in about twenty longitudinal rows. Mouth little constricted. Peristome broad ; in the upper

1284 THE VOYAGE OF H.M.S. CHALLENGER.

half a hyaline, circular ring, in the lower half divided into from eighteen to twenty-four triangular,
curved, little convergent feet.

Dimensions. — Cephalis 0'02 long, 0'05 broad ; thorax 01 long, 0'09 broad.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific ; many stations, at various depths.

17. Carpocanium coronatum, Ehrenberg.

Carpocanium coronatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. v.

% 7.

Shell ovate, smooth, with perfectly hidden, subspherical cephalis. Length of the two
joints = 2 : 9, breadth = 2 : 8. Pores small and very numerous, twice as broad as the bars,
regular, circular, in about twenty longitudinal rows. Mouth little constricted, two-thirds as broad
as the thorax. Peristome with twenty-five to thirty short, bristle-shaped feet, which are slightly
curved, convergent, and in the upper half connected by a solid ring.

Dimensions. — Cephalis 0'02 long, 0'02 broad; thorax 0'09 long, 0'08 broad.

Habitat. — Fossil in Barbados.

18. Carpocanium dactylus, n. sp.

Shell slenderly ovate, twice as long as broad, with flat, perfectly hidden cephalis. Length
of the two joints = 1 : 12, breadth = 4 : 8. Pores subregular, circular, as broad as the bars,
in about twelve longitudinal rows, separated by prominent longitudinal ribs. Mouth con-
stricted, two-thirds as broad as the thorax. Peristome with twelve large, lanceolate, lamellar,
convergent feet.

Dimensions. — Cephalis O'Ol long, 0'04 broad; thorax 012 long, 0'08 broad.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

19. Carpocanium irregulare, n. sp. (PI. 52, fig. 14).

Shell irregular, roundish; subovate, with flat and oblique, perfectly hidden cephalis. Length of
the two joints = 1 : 10, breadth = 3 : 9. Pores irregularly scattered, roundish, about as broad as the
bars. Mouth wide open, not at all or little constricted. Peristome with twenty to thirty long,
lamellar, pointed feet, which are irregularly curved and convergent.

Dimensions. — Cephalis O'Ol to 0'02 long, 0'03 to 0'04 broad ; thorax 0'09 to Oil long, 0'08 to
0-09 broad.

Habitat. — Central Pacific, Station 263 to 274, surface, and at various depths.

20. Carpocanium verecundum, n. sp. (PI. 52, figs. 12, 13).

Shell ovate, smooth, with flat, perfectly hidden cephalis (fig. 12). Length of the two joints =
1 : 9, breadth = 4:9. Pores subregular, circular, twice as broad as the bars, in about eighteen,

REPORT ON THE RADIOLARIA. 1285

partly interrupted, longitudinal rows, separated by prominent crests. Mouth little constricted.
Peristome with twenty to twenty-four broad, lamellar, pointed feet, which are about as long as the
shell, little curved, and convergent.

Dimensions. — Cephalis O'Ol long, 0'04 broad ; thorax 0'09 long, 0'09 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

21. Carpocanium virgineum, n. sp. (PL 52, fig. 20).

Shell ovate, smooth, with flat, perfectly hidden cephalis. Length of the two joints = 1:8, breadth
= 3:9. Pores regular, circular, hexagonally framed, as broad as the bars, in about sixteen longi-
tudinal rows on each side. Mouth little constricted. Peristome with eighteen to twenty -four very
large, lamellar, pointed feet, which are longer than the shell, and so curved and convergent that
their distal points come nearly in contact.

Dimensions. — Cephalis O'Ol long, 0'03 broad ; thorax 0'08 long, 0'09 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subfamily 2. SETHOPH^NIDA, Haeckel, 1881, Prodromus, p. 433.

Definition. — A nthocyrtida with the basal mouth of the shell fenestrated
(vel Dicyrtida multiradiata clausa).

Genus 570. Sethophcena,1 Haeckel, 1881, Prodromus, p. 433.

Definition. — S ethophsenida (vel Dicyrtida multiradiata clausa) with lateral
apophyses. Cephalis with a horn.

The genus Sethophcena aud the following Clistophcena form together the small sub-
family of Sethophsenida, comprising those Dicyrtida in which the thorax bears numerous
radial appendages (four to six or more), and the mouth is closed by a lattice-plate. In
Sethophcena the apophyses are lateral wings, as in Micromelissa, from which it may be
derived by development of secondary wings, interpolated between the three primary
wings.

1. Sethophcena tetraptera, n. sp.

Shell smooth, with deep collar stricture. Length of the two joints = 3:10, breadth =
4 : 9. Cephalis subspherical, without horn. Thorax ovate, with rounded hemispherical base, and
subregular, hexagonal pores. From its upper half (below the collar stricture) arise four divergent,

1 Sethophoena= Sieve-shell ; oi$a, (pair*.

1286 THE VOYAGE OF H.M.S. CHALLENGER.

conical, straight wings, of half the length, opposite in pairs in two meridional planes, perpendicular
to one another (compare Tetralacorys, PL 65, figs. 4, 5).

Dimensions. — Cephalis 0'03 long, 0'04 broad; thorax 01 long, 0'09 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

2. Sethophcena hexaptera, n. sp. (PL 97, fig. 13).

Shell rough, pear-shaped, with distinct collar stricture. Length of the two joints = 1:4,
breadth = 2:4. Cephalis hemispherical, with a conical horn of the same length. Thorax innate,
inversely ovate, nearly pear-shaped, with subregular, circular pores. From its upper half arise, by a
broad base, six divergent, strong, conical wings, which are horn-like, curved downwards, and half as
long as the thorax.

Dimensions. — Cephalis 0'025 long, 0'04 broad ; thorax 0'09 long, 0'08 broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Sethophcena enneaptera, n. sp.

Shell rough, with sharp collar stricture. Length of the two joints = 1 : 6, breadth = 1 : 3.
Cephalis subspherical, with a stout conical horn of twice the length. Thorax inversely ovate, with
pointed, conical, basal part, and irregular, roundish pores. From its middle part arise, by a broad
triangular base, nine compressed, divergent wings, which are a little curved, slender, and about as
long as the thorax.

Dimensions. — Cephalis 0'025 long, 0'03 broad ; thorax 017 long, 01 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Sethophcena polyptera, n. sp.

Shell thorny, with slight collar stricture. Length of the two joints = 1 : 10, breadth = 3:8.
Cephalis flat, cap-shaped, without horn. Thorax pear-shaped, with hemispherical base and regular,
circular pores. From its lower half (beyond the equator) arises a corona of numerous short
conical wings (eighteen to twenty-four), which are a little curved, and divergent downwards, scarcely
one-third as long as the thorax.

Dimensions. — Cephalis 0'015 long, 0'04 broad ; thorax 015 long, 012 broad.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

Genus 571. Clistophcena, Haeckel, 1881, Prodromus, p. 433.

Definition. — S ethophsenida (vel Dicyrtida multiradiata clausa) with terminal
apophyses. Cephalis with a horn.

1 Clistophcena = Closed shell ; <fi)(u, (p tiiva,.

REPORT ON THE RADIOLARIA. 1287

The genus Clistoplicena agrees with the preceding Sethophcena in the mouth of the
thorax being closed by a lattice-plate. But the appendages of the thorax are terminal
feet, not lateral wings; their number is commonly six or nine, rarely more. Clistophcena
may be derived either from Tetrahedrina by interpolation of secondary feet between
the three primary, or from Sethamphora by development of a basal lattice -plate closing
the mouth.

1. Clistophcena rustiana, n. sp. (PI. 57, fig. 6).

Shell rough, with distinct collar stricture. Length of the two joints = 3 : 10, breadth = 4 : 11.
Cephalis hemispherical, with small, circular pores and a stout oblique horn three times the length,
which is three-sided prismatic, and at the top denticulate. Thorax subconical, inflate, with
regular, circular, quincuncial pores, increasing in size towards the base. Margin of the flat base,
with six divergent, stout feet of the same prismatic form as the cephalic horn, with denticulate
distal ends, about as long as the thorax. This elegant species is dedicated to Dr. Exist of Freiburg,
the discoverer of numerous fossil Eadiolaria in the Ldassic and Jurassic formations.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax O'l long, O'll broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Clistophcena hexolena, n. sp.

Shell smooth, with slight collar stricture. Length of the two joints = 1:4, breadth = 1:5.
Cephalis subspherical, small, with a large, vertical, cylindrical horn, about as long as the shell,
and small, circular pores. Thorax nearly three-sided pyramidal or tetrahedral, with three
rounded edges and subregular, circular pores. Margin of the flat base with six conical, divergent,
straight feet, somewhat shorter than the thorax. (Three on the corners, one on the middle of each
side of the triangular base.)

Dimensions.- — Cephalis O'OS diameter, thorax 0'12 long, 0'14 broad.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

3. Clistophcena pyramidalis, n. sp.

Shell smooth, with slight collar stricture. Length of the two joints = 2 : 8, breadth = 3 : 10.
Cephalis hemispherical, with a stout pyramidal horn of twice the length. Thorax six-sided
pyramidal, with regular, circular pores of equal size, and six prominent, straight edges, which are
prolonged into six divergent, pyramidal feet of half the length.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax O'OS long, 01 broad.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

1288 THE VOYAGE OF H.M.S. CHALLENGER.

4. Clistophcena armata, n. sp. (PL 57, fig. 7).

Shell spiny, with deep collar stricture. Length of the two joints = 4 : 18, breadth = 5 : 15.
Cephalis subspherical, with small, circular, hexagonally-framed pores, and a stout, three-sided
prismatic, cuspidate horn of the same length. Thorax pear-shaped, with regular, circular pores
and three pairs of stout pyramidal wings, placed in the three primary meridional planes of the
collar beams ; three of them lie in the upper, and three in the lower third of the thorax. Margin
of the flat Base with nine cylindrical, somewhat club-shaped, divergent feet.

Dimensions. — Cephalis 0'04 long, O05 broad ; thorax 0'18 long, 0'15 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

5. Clistophcena enneolena, n. sp.

Shell spiny, with sharp collar stricture. Length of the two joints = 4 : 20, breadth 5 : 16 .
Cephalis hemispherical, hyaline, with a stout conical horn of the same length and some small
accessory horns. Thorax ovate, spiny, with subregular, circular pores. Margin of the vaulted
base with nine divergent, conical feet, half as long as the thorax.

Dimensions. — Cephalis 0'04 long, 0'05 broad; thorax 0'2 long, 016 broad.

Habitat. — South Pacific, Station 296, depth 1825 fathoms.

6. Clistophcena polyolena, n. sp.

Shell smooth, conical, with obliterated collar stricture. Length of the two joints = 1:5,
breadth = 2:5. Cephalis hemispherical, with small, circular pores and two divergent conical
horns (a major occipital and a smaller frontal horn). Thorax obtusely conical, with regular,
hexagonal pores at the mantle, and circular pores in the basal plate, the margin of which bears
eighteen vertical, parallel, conical feet, as long as the cephalis.

Dimensions. — Cephalis 0'015 long, 0'025 broad ; thorax O'OS long, 0'08 broad.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

Family LXIV. — S ETHOCYRTIDA, n. fam.

Sethocorida et Sethocapsida, Haeckel, 1881, Prodromus, pp. 439, 433.

Definition. — D icyrtida eradiata. (Cyrtoidea with a two-jointed shell,
divided by a transverse constriction into cephalis and thorax, without radial apophyses).

The family Sethocyrtida, composed of the Sethocorida and Sethocapsida of my
Prodromus, comprises those Cyrtoidea in which the shell is two-jointed and bears no
radial apophyses. The two subfamilies differ in the shape of the mouth, which in the
Sethocorida is a simple wide opening, and in the Sethocapsida is closed by a lattice- plate.
The former are here divided into eight, the latter into three genera,

REPORT ON THE RADIOLARIA.

1289

Numerous living and fossil forms of Setliocyrtida were previously described by
Ehrenberg, partly in his genera Dictyocephalus and Lophophcena, partly (intermingled
with three-jointed and many-jointed forms) in the genera Eucyrtidium and Liihocampe.
A larger number of new forms has been found in the Radiolarian ooze collected by the
Challenger, and others fossil in Barbados. Many of these Sethocyrtida are common and
widely distributed. When a new third joint is formed on their basal mouth, they pass
over into Theocyrtida.

The cephalis is usually subspherical or hemispherical, and much smaller than the
thorax, the form of which exhibits all possible intermediate stages between flat, discoidal,
conical, cylindrical, and ovate forms. The wide open mouth becomes more and more
constricted, and finally closed in the Sethocapsida. The majority of the Sethocyrtida
may have been derived either from the Tripocyrtida, or from the Anthocyrtida by
reduction and loss of the radial apophyses.

Synopsis of the Genera of Sethocyrtida.

I. Subfamily

Sethocorida.
Terminal mouth of the \
thorax a simple wide
opening

II. Subfamily

Sethocapsida.
Terminal mouth closed
by a lattice-plate. !

Thorax conical or campanu-
late, gradually dilated.

Thorax discoidal, flatly ex-
panded.

Thorax cylindrical or ovate,
with truncate, constricted
or tubular mouth.

n i. v t .1-11 •

Cephalis free, not hidden in

the thorax.

Cephalis hidden in the ( ^ ,

, ., ., < .No horn,

upper part of the thorax. \

f Shell simple, without mantle, . 572. Sethoconus.

Shell double, with an arach-
noidal mantle,

( Cephalis very large, without
1 horn,

f Cephalis ( Mouth simple,

with a *
single horn. ( Mouth tubular,

Cephalis with two horns or a
bunch of horns,

[ Cephalis without horn,
One horn,

573. PeriararJtnium.

574. Sethocephalus.

575. SetJwcyrtis.

576. Sethocorys.

577. Loplwpluena.

578. Dictyocephalus.

579. Sethocapsa.

580. Dicolocapsa.

581. Crypiocapsa.

Subfamily 1. SETHOCORIDA, Haeckel, Prodromus, p. 430.

Definition. — S ethocyrtida with the basal mouth of the shell open (vel Dicyrtida
eradiata aperta).

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Kr 162

1290 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 572. Sethoconus,1 Haeckel, 1881, Prodromus, p. 430.

Definition. — S ethocorida (vel Dicyrtida eradiata aperta) with conical or
campanulate, gradually dilated thorax and wide open mouth. Cephalis with one or
more horns.

The genus Sethoconus is the oldest and simplest form of the Sethocorida, or of those
Dicyrtida in which the simple thorax bears no apophyses and has the mouth open and not
closed by a basal lattice-plate. Probably all those eradiate Sethocorida have been derived
either from triradiate Sethopilida (Lychnocanium) , or from multiradiate Sethophormida
(Sethophormis, Anthocyrtis ?) by loss of the radial ribs and feet. In Sethoconus the thorax
is more or less conical, sometimes more campanulate, commonly smooth, in some
species covered with spines. The cephalis is usually small, with rudimentary collar
septum, at other times large, with distinct cortinar septum. Correspondingly, the genus
may be divided into different groups, which here are enumerated as subgenera,

Subgenus 1. Conarachnium, Haeckel, 1881, Prodromus, p. 430
( = Ceratocyrtis, Biitschli), 1882, loc. cit., p. 536.

Definition. — Cephalis relatively large, with distinct collar septum and numerous
pores. Thorax smooth.

1. Sethoconus trochus, Haeckel.

Eucyrtidium trochus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293,

Taf. vii. fig. 17.
Conarachnium trochus, Haecksl, 1881, Prodromus, p. 430.

Cephalis ovate, relatively large, with a pyramidal horn of the same length, and three pairs of
large opposite pores, on each side of a vertical septum. Thorax wide, conical, about as long as
broad, with nearly straight outlines ; its pores regular, circular, hexagonally framed, of the same
size as the cephalic pores.

Dimensions. — Cephalis 0'03 long, O02 broad; thorax 0'06 long, 0-06 broad.
Habitat. — Tropical Pacific, Stations 200 to 281, surface.

2. Sethoconus cucullaris, Haeckel.

Cm-nutella cucullaris, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii.

fig. 7.
Ceratocyrtis cucullaris, Biitschli, 1882, Zeitschr. f. wiss. Zool., Bd. xxxvi. p. 536, Taf. xxxiii.

fig. 36, a. b.

Cephalis subspherical, thorny, relatively large, with a conical horn of the same length, and small
circular pores. Thorax wide, conical, enveloping the lower hidden half of the cephalis, about as

1 Sethoconus = Sieve-cone ; oySa, »ai/o{.

REPORT ON THE RADIOLARIA. 1291

long as broad, with slightly convex outlines ; its pores subregular, circular, half as broad as the
cephalis.

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 015 long, 014 broad.

Habitat. — Fossil in Barbados.

3. Sethoconus pileus, n. sp.

Cephalis subspherical, free, with distinct collar stricture, a conical oblique horn of the same
length, and small, irregular, roundish pores. Thorax flatly conical, about half as long as broad, with
straight outlines ; its pores subregular, hexagonal, half as broad as the cephalis, with very thin
bars.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'08 long, 016 broad.

Habitat. — Central Pacific, Stations 262 to 274, surface.

4. Sethoconus ampliatus, Haeckel.

Cornutella ampliata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii. fig. 5.
Ceratocyrtis ampliata, Biitschli, 1882, Zeitschr. f. wiss. Zool., Bd. xxxvi. p. 536.

Cephalis, hemispherical, thorny, with a conical horn of twice the length; it is separated from
the thorax by a complete internal collar septum, but without external collar stricture. Thorax
flatly conical, about half as long as broad, with straight outlines ; its pores subregular, hexagonal,
about as large as the cephalis, with thin bars.

Dimensions. — Cephalis 0'015 long, 0'03 broad ; thorax 0'08 long, 018 broad.

Habitat. — Fossil in Barbados.

5. Sethocdnus mitra, Haeckel.

Cornutella mitra, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii. fig. 8.
Ceratocyrtis mitra, Biitschli, 1882, Zeitschr. f. wiss. Zool., Bd. xxxvi. p. 536.

Cephalis ovate, with slight collar stricture (not distinct enough in Ehrenberg's figure), with
few large pores, and a conical stout horn of the same length. Thorax campanulate, conical, twice as
long as broad, with slightly convex outlines ; its pores subregular, roundish, increasing in size
towards the mouth, the largest as broad as the cephalis.

Dimensions. — Cephalis, 0'03 long, 0'02 broad ; thorax 012 long, 0'07 broad.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms ; fossil in Barbados.

6. Sethoconus rayianus, n. sp. (PI. 58, fig. 6)

Conarachnium rayianum, Haeckel, 1881, Prodromus, p. 430.

Cephalis ovate, with obliterated collar stricture (but distinct internal septum), with small,
irregular pores, and two to four divergent horns, which are longer than the cephalis, and two or
three of which are forked. Thorax tent-shaped, conical, two-thirds as long as broad, with slightly

1292 THE VOYAGE OF H.M.S. CHALLENGER.

concave outlines, and subregular, hexagonal pores, gradually increasing towards the mouth, the
largest half as broad as the cephalis. This elegant species is dedicated to Dr. Ray, the discoverer
of many rare Eadiolarians in the Challenger collection.

Dimensions. — Cephalis 0'03 long, 0'02 broad ; thorax 0'08 long, 012 broad.

Habitat. — Central Pacific, Stations 266 to 272, surface.

7. Sethoconus cervus, Haeckel.

1 Eucyrtidium cervus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 291, Taf. ix.

fig. 21.
Conarachnium cervus, Haeckel, 1881, Prodromus, p. 430.

Cephalis subspherical, with slight collar stricture, small circular pores, and two to four divergent
horns, one or two of which are forked. Thorax wide, conical, about as long as broad, with straight
outlines and irregular, polygonal pores, gradually increasing towards the mouth ; the largest as
broad as the cephalis.

Dimensions. — Cephalis 0'015 long, 0'02 broad ; thorax O'OS long, 0'08 broad.

Habitat. — Indian Ocean ; Maldive Islands, surface (Haeckel) ; Zanzibar, depth 2200 fathoms
(Pullen).

8. Sethoconus lophophcena, n. sp.

Conarachnium lophophcvna, Haeckel, 1881, Prodromus, p. 430.

Cephalis subspherical, with distinct collar stricture, small circular pores, and numerous (twelve
to sixteen) radial, bristle-shaped horns of different lengths. Thorax wide, conical, somewhat longer
than broad, with slightly convex outlines, and subregular, hexagonal pores, increasing gradually in
size towards the mouth ; the largest twice as broad as the cephalis.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'2 long, 016 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

9. Sethoconus larvatus, Haeckel.

Lophophasna larvata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. viii.

fig. 10.
Dictyoceplialus larvatus, Biitschli, 1882, Zeitschr. f. wiss. Zool., Bd. xxxvi. p. 535.

Cephalis subspherical, large, with sharp collar stricture, and numerous (five to ten or more)
radial, conical (partly forked) horns of different lengths. Thorax wide, conical, somewhat broader
than long, with straight outlines. Pores of both joints very irregular, roundish, of very different
sizes and form.

Dimensions. — Cephalis 0'04 long, 0'05 broad ; thorax 01 long, 012 broad.

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1293

10. Sethoconus nassa, Haeckel.

Eucyrtidium nassa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. ix. fig. 9.

Cephalis slenderly ovate, with sharp collar stricture, few scattered pores, and a very stout, pyra-
midal horn of the same length, which is surrounded at the base by three short, divergent, ascending
spines (perhaps the remnants of the three cortinar rods of Eiwecryplialus, &c. ?). Thorax slender,
conical, with straight outlines, and small, dense, regular, circular pores of equal size.

Dimensions. — Cephalis 0'04 long, 0'02 broad ; thorax 012 long, 0'08 broad.

Habitat. — Fossil in Barbados.

11. Sethoconus tabulatus, Haeckel.

Cydadophora tabulata, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 289,

Taf. iv. fig. 18.

Cephalis subspherical, with slight collar stricture, and numerous small, irregular pores, without
horn, or with a small conical horn. Thorax slenderly conical, with straight outlines, and large,
regular, hexagonal pores. Mouth truncate. (In the specimen I examined the thorax was longer
and more conically dilated ; the cephalis had a distinct small horn.)

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'08 long, 0'06 broad.

Habitat. — North Atlantic, Antilles, depth 1600 fathoms (Ehrenberg); Station 347, depth 2250
fathoms.

Subgenus 2. Cornutettium (vel Ceratar actinium), Haeckel, 1881, Prodromus, p. 430.

Definition. — Cephalis very small, rudimentary, hyaline, without distinct collar
septum, and without pores (or with scarce, rudimentary pores). Thorax smooth.

12. Sethoconus hexagonalis, Haeckel.

Cornutella troclms, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. ix. fig. 14.

Cephalis very small, subspherical, hyaline, without pores, with a rudimentary horn of half the
length. Thorax slenderly conical, or bottle-shaped, twice to three times as long as broad ; in the
lower half nearly cylindrical, with very thin, thread-like bars, and regular, hexagonal pores,
increasing in size towards the mouth.

Dimensions. — Cephalis O'OOS diameter, thorax 012 long, 0'05 broad.

Habitat. — Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).

13. Sethoconus verrucosus, Haeckel.

Cornutella verrucosa, Ehrenberg, 18
fig. 16.

Cephalis very small, subspherical, hyaline, without pores, with a rudimentary horn of half the

Cornutella verrucosa, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. is.
fig. 16.

1294 THE VOYAGE OF H.M.S. CHALLENGER.

length. Thorax slenderly conical, or bottle-shaped, with little convex outlines ; three to four times
as long as broad, papillate, with regular, circular pores, which are included by rhombic frames, and
increase in size towards the mouth.

Dimensions. — Cephalis 0'004 diameter, thorax 0'12 long, O035 broad.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms (Pullen).

14. Sethoconus orthoceras, n. sp. (PL 54, fig. 11).

Gornutella orthoceras, Haeekel, 1879, Atlas, loc. cit.

Cephalis very small, conical, hyaline, without pores, with a double internal stricture, and a very
short, rudimentary horn. Thorax slenderly conical, with undulate outlines, three to four times as
long as broad, with subregular, roundish pores, gradually increasing in size towards the mouth.

Dimensions. — Cephalis 0'02 long, O'Ol broad ; thorax 0'16 long, 0'04 to 0'08 broad.

Habitat.— South Atlantic, Station 325, surface.

15. Sethoconus profundus, Haeekel.

Gornutdla profunda, Ehrenberg, 1854, Mikrogeol., Taf. xxxv. B, Nr. B. iv. fig. 21.
Gornutella profunda, Bailey, 1856, Aincr. Jour., vol. xxii. pi. i. fig. 23.
Comutella profunda, Haeekel, 1862, Monogr. d. Eadiol., p. 284.

Cephalis very small, spherical, hyaline, without pores and internal stricture, with a very short,
rudimentary horn. Thorax slenderly conical, with straight outlines, three to four times as long as
broad, with subregular, circular pores, gradually increasing in size towards the mouth.

Dimensions. — Cephalis 0'004 to O'OOS diameter, thorax 0'08 to 0'12 long, 0'03 to 0'04 broad.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific ; at various depths.

16. Sethoconus trichostylus, Haeekel.

tCornutella trichostyla, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287,

Taf. vi fig. 2.

Cephalis very small, conical, hyaline, without pores, with a very long, bristle-shaped, spirally
twisted horn, longer than the whole shell. Thorax slenderly conical, with straight outlines, and
very small, regular, circular pores of nearly equal size, which are separated by broader bars and
spirally ascending oblique crests (according to the figure).

Dimensions. — Cephalis 0'004 long, 0-002 broad ; thorax 0'06 long, 0'04 broad.

Habitat. — North Pacific (California), depth 2600 fathoms.

17. Sethoconus lonqisetus, Haeekel.

Cornutella longjseta, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. ix.
fig. 15.

Cephalis very small, spherical, hyaline, without pores, with a very long, bristle-shaped horn,

REPORT ON THE RADIOLARIA. 1295

nearly as long as the shell. Thorax slenderly conical, rough, with straight outlines, and irregular,
roundish pores, gradually increasing in size towards the mouth.

Dimensions. — Cephalis O'Ol diameter, thorax 0'09 long, 0'03 broad.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms (Pullen).

18. Sethoconus gracilis, Haeckel.

Ewyrtidium gracile, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi.
fig. 15.

Cephalis small, subspherical, with few scarce pores, and a stout, pyramidal horn, of the same
length. Thorax slenderly conical, three to four times as long as broad, with straight outlines, and
very small and numerous circular pores of equal size.

Dimensions. — Cephalis 0'015 diameter, thorax 012 long, 0'04 broad.

Habitat. — Fossil in Barbados.

19. Sethoconus bimarginatus, n. sp. (PL 54, fig. 12).

Coniutella bimarginata, Haeckel, 1879, Atlas, loc. dt.

Cephalis very small, subspherical, hyaline, without pores, with a rudimentary, conical horn of the
same length. Thorax slenderly conical, three times as long as broad, with undulated, little convex
outlines, and irregular, roundish, double-contoured pores, arranged in nine longitudinal series,
markedly increasing in size towards the mouth.

Dimensions. — Cephalis O'Ol diameter, thorax 016 long, 0'05 broad.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

20. Sethoconus daihratus, Haeckel.

Cornutella clathrata, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 39a, b, c.

Cephalis very small, subspherical, hyaline, without pores, with a rudimentary horn of half the
length. Thorax slenderly conical, three to four times as long as broad, smooth, with curved axis and
small, regular, circular pores, nearly equal in size. This common species differs from all others of
the genus by the curvation of the axis of the shell, which is more or less crescentic, or curved like a
cowherd's horn ; it may, therefore, represent a peculiar genus, Sethodrepanum.

Dimensions. — Cephalis 0'003 to 0'006 diameter, thorax 0'08 to 016 long, 0'03 to 0'05 broad.

Habitat. — Cosmopolitan ; Atlantic, Pacific, many stations ; fossil in Barbados and Sicily.

Subgenus 3. Phlebarachnium, Haeckel (et Cladarachnium, Haeckel), 1881,

Prodromus, p. 430.

Definition. — Cephalis small, with very small pores, and internal collar septum.
Thorax spiny or thorny.

1296 THE VOYAGE OF H.M.S. CHALLENGE!!.

21. Sethoconus facetus, n. sp. (PI. 55, fig. 1).

Phlebarachnium facetum, Haeckel, 1881,'Prodromus, p. 430.

Cephalis small, hemispherical, with distinct collar septum, the same network as the thorax,
and numerous bristle-shaped horns of the same length. Thorax wide, conical, about as long as
broad, with slightly convex outlines ; its network extremely delicate, with very small and numerous,
regular, hexagonal pores, disposed in numerous divergent, longitudinal series, which are convoluted
somewhat spirally around the shell axis. Surface covered with thin, scattered, bristle-shaped spines,
about as long as the cephalis.

Dimensions. — Cephalis O02 diameter, thorax 02 long, 022 broad.

Habitat. — Central Pacific, Stations 271 to 274, surface.

22. Sethoconus anthocyrtis, n. sp. (PI. 62, fig. 21).

Anthocyrtis sethocomts, Haeckel, 1879, Atlas, loc. cit.

Cephalis small, subspherical, with very small pores and numerous radial, bristle-shaped spines
of the same length. Thorax wide, conical, about as long as broad, with parabolic outlines, its net-
work very delicate, with subregular, hexagonal meshes. Surface with scarce, bristle-shaped spines
(not represented in the figure). Mouth with a corona of numerous small, vertical spines.

Dimensions. — Cephalis 0'025 diameter, thorax 026 long, O24 broad.

Habitat. — North Pacific, Station 248, surface.

23. Sethoconus virgultus, n. sp.

Cladaraclinium virgultum, Haeekel, 1881, Prodromus, p. 430.

Cephalis and thorax nearly of the same form and stricture as in Sethocomis facetus, but larger
and wider, with the same delicate, hexagonal network (PI. 55, fig. 1) ; it differs from the latter by
the wider, more convex and campanulate form, but mainly by the armature of the surface, which is
densely covered with thin, arborescent, bristle-shaped spines, irregularly branched, and four to eight
times as large as the cephalis.

Dimensions. — Cephalis 0'02 diameter, thorax O32 long, 0'4 broad.

Habitat. — South Pacific, Station 288, surface.

24. Se,thoconus setosus, n. sp.

Phltbarachnium setosum, Haeckel, 1881, Prodromus, p. 430.

Cephalis small, subspherical, with distinct collar septum, and the same network as the thorax,
with numerous bristle-shaped horns of the same length. Thorax slenderly conical, twice as long as
broad, with irregular, polygonal pores of little different sizes, and very thin bars. Surface covered
with perpendicular, simple, bristle-shaped spines, about as long as the cephalis.

Dimensions. — Cephalis 0'02 diameter, thorax 012 long, 0'22 broad.

Habitat.— Central Pacific, Stations 266 to 272, surface.

REPORT ON THE RADIOLARIA. 1297

25. Sethoconus venosus, n. sp. (PL 55, fig. 2).

Pldeliaracliniiim venosum, Haeckel, 1881, Prodromus, p. 430, et Atlas, loc. cif.

Cephalis subspherical, with a stout prismatic horn twice the length, bearing three denticu-
late edges. The uppermost part of the thorax is supported by three diverging, radial beams
arising from the deep collar stricture. Thorax wide, conical, nearly twice as long as broad, with
slightly convex, thorny outlines ; its delicate network is composed of very irregular, polygonal
meshes of different sizes, separated by stronger bars, and of numerous very small polygonal pores
separated by very thin bars inside the former. The central capsule of the figured specimen
exhibited in the upper third of the thorax four large club-shaped lobes, which arose from a very
small sphere enclosed in the cephalis and containing the nucleus.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'4 long, 0'3 broad.

Habitat. — Central Pacific, Station 271, surface.

Genus 573. Periarachnium,1 Haeckel, 1881, Prodromus, p. 430.

Definition.— -S ethocorida (vel Dicyrtida eradiata aperta) with conical or cam-
panulate, gradually dilated thorax, and widely open mouth. Primary lattice - shell
enveloped by an external arachnoidal mantle. Cephalis with one or more horns.

The genus Periarachnium has been derived from those forms of the preceding
Sethoconus, in which the conical thorax is covered with simple spines (Phlebarachnium)
or branched spines (Cladarachnium). By communication of the branches of these
spines a second outer shell is formed, which, like an arachnoidal mantle, envelops the
inner primary shell.

1. Periarachnium periplectum, n. sp. (PL 55, fig. 11).

Cephalis hemispherical, separated from the thorax by a sharp collar stricture, from which
arise three internal, diverging beams supporting its upper third. Thorax campanulate, conical,
about as long as broad, with slightly convex outlines. The delicate lattice-work of the entire shell
is double ; the inner composed of subregular, hexagonal meshes ; the outer of larger, irregular,
polygonal meshes. The bars of the inner are much thicker than the thin threads of the outer.
Both shells are connected by numerous bristle-shaped beams. The central capsule of the figured
specimen exhibited in the upper part of the thorax three club-shaped lobes, which arose from
a sphere enclosed in the cephalis and containing the nucleus.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'15 long, 012 broad.

Habitat. — Central Pacific, Station 271, surface.

1 Periarachniurn = Shell enveloped by cobweb; »«{/, dactjcainy.
(ZOOL. CHALL. EXF. — PART XL. — 1886.) Rr 163

1298 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 574. Sethocephalus,1 Haeckel, 1881, Prodromus, p. 430.

Definition. — S ethocorida (vel Dicyrtida eradiata aperta) with discoidal, flatly
expanded thorax. Cephalis large, without horn.

'The genus Sethocephalus (formerly proposed under the name Platycryphalus)
contains some few and rare Sethocorida, distinguished by the very large cephalis, the
collar opening of which is wide open, not closed by cortinar beams, and surrounded by
a very flat, nearly discoidal thorax, like the brim of a hat. It is possible that this
peculiar genus has been derived from a Tricyrtid (TJieocalyptra ?) by loss of the
original cephalis, and that the apparent large cephalis is the original thorax.

1. Sethocephalus eucecryphalus, n. sp. (PI. 56, fig. 13).

Cephalis very large, campanulate-conical, with irregular, polygonal pores and thin bars. Thorax
short, scarcely broader than the cephalis, beyond the sharp collar stricture expanded like the brim of
a hat, with few rows of irregular, polygonal pores. (In the specimen figured the thorax was only
half as broad as in another specimen found afterwards.)

Dimensions. — Cephalis 012 long, 0'09 broad; thorax O02 long, 012 broad.

Habitat. — South Pacific, Station 285, surface.

2. Sethocephalus platycryphalus, u. sp.

Platycryphalus sethodiscus, Haeckel, 1881, Prodromus, p. 430.

Cephalis large, hemispherical, with irregular square pores and thin bars. Thorax flatly conical,
three to four times as broad as the cephalis, beyond the collar stricture expanded nearly discoidally,
with a delicate network of small, subregular, hexagonal pores. (Similar in general form to
Scthophormis aurelia, PI. 55, fig. 3, but without any trace of collar beams or radial ribs.)

Dimensions. — Cephalis 0'04 long, O08 broad ; thorax 0'04 long, 0'3 broad.

Habitat. — South Pacific, Station 289, surface.

Genus 575. Sethocyrtis,2 n. gen.

Definition. — Sethocorida (vel Dicyrtida eradiata aperta) with ovate or
subcylindrical thorax, the mouth of which is constricted, simple, without prominent
hyaline peristome. Cephalis with an apical horn.

1 Sethocephalus=S>ieve-hea<l ; aii6u,

2 Sethocyrtis - Sieve-basket ; aq0u, x

REPORT ON THE RADIOLARJA.-

The genus Sethocyrtis and the three following nearly allied genera differ from the
three preceding genera of Sethocorida in the form of the thorax, which is not gradually
dilated, conical, but cylindrical or ovate, with more or less constricted mouth.
Sethocyrtis may be derived from Anthocyrtis by loss of the terminal feet. Its mouth
is quite simple, without tubular or annular peristome.

1. Sethocyrtis oxy cephalis, n. sp. (PL 62, fig. 9).

Shell rough, subconical, with slight collar -stricture. Length of the two joints = 4 : 9, breadth =
3 : 8. Cephalis ovate, with a pyramidal horn of half the length. Thorax campanulate, with regular,
circular pores, twice as broad ' as those of the cephalis. Mouth constricted, scarcely half as broad
as the thorax.

Dimensions. — Cephalis 0'04 long, O03 broad ; thorax 0'09 long, 0'08 broad.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 3000 fathoms.

2. Sethocyrtis cancrina, Haeckel.

Eucyrtidium cancrinum, Ehrenberg, 1875, Abhandl. d. k, Akad. d. Wiss. Berlin, p. 70, Taf. x.

fig. 4.

Shell smooth, bottle-shaped, with obliterated collar stricture. Length of the two joints = 4 : 9,
breadth = 2:7. Cephalis subcylindrical, with a stout conical horn of the same length, and some-
times a smaller accessory horn at its base. Thorax ovate, truncate, with regular, circular, quin-
cuncial pores, twice as broad as those of the cephalis. Mouth little constricted, flat, nearly as broad
as the thorax.

Dimensions. — Cephalis 0'04 long, 0-02 broad ; thorax 0'09 long, 0'07 broad.

Habitat. — Fossil in Barbados.

3. Sethocyrtis diomedis, n. sp.

Shell thorny, pear-shaped, with slight collar stricture. Length of the two joints = 3 : 16, breadth
= 4 : 20. Cephalis hemispherical, with a conical horn of twice the length. Thorax inflate, ovate,
truncate at both poles, with regular, circular pores, twice as broad as those of the thorax. Mouth
constricted, flat, half as broad as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'12 to 016 long, 0'16 to 0'2 broad.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms,; also fossil in
Barbados.

4. Sethocyrtis menelai, 11. sp.

Shell spiny, pear-shaped, with sharp collar stricture. Length of the two joints = 3:15, breadth =
18. Cephalis subspherical, with a large, cylindro-conical horn, about as long as the whole shell.

1300 THE VOYAGE OF H.M.S. CHALLENGER.

Thorax inflate, subspherical, truncate, with large, irregular, roundish pores, four to six times as large
as those of the cephalis. Mouth constricted, flat, one-third as broad as the thorax.

Dimensions. — Cephalis 0'03 long, 0'04 broad; thorax 015 long, 018 broad.

Habitat. — Fossil in Barbados.

5. Sethocyrtis subacuta, Haeckel.

Eucyrtidium subacutum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293, Taf. vii.

fig. 18.

Shell smooth, pear-shaped, with sharp collar stricture. Length of the two joints = 1:4,
breadth = 1:3. Cephalis subspherical, with small, irregular pores and a rudimentary horn of half
the length. Thorax ovate, with large, subregular, hexagonal pores and thin bars between them.
Mouth constricted, flat, half as broad as the thorax, without prominent peristome.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'08 long, O'OG broad.

Habitat. — Philippine Sea, depth 3300 fathoms (Ehrenberg).

6. Sethocyrtis pleuracantha, Haeckel.

Eucyrtidium pleuracantkum, Elirenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293,

Taf. vii. fig. 21.

Shell smooth, bottle-shaped, with distinct collar stricture. Length of the two joints = 2:4
breadth = 1:3. Cephalis slenderly ovate, with an excentrie pyramidal horn of the- same length.
Thorax inflate, ovate, with irregular, roundish pores and thin bars between them. Mouth con-
stricted, flat, half as broad as the thorax, without prominent peristome.

Dimensions. — Cephalis 0'04 long, 0'02 broad; thorax 0'08'long, 0'06 broad.

Habitat. — Tropical Pacific, Stations 200, 225, 266, 274, &c,, at various depths.

7. Sethocyrtis agamemnonis, n. sp. (PI. 62, figs. 11, a, I).

Shell pear-shaped, rough, with sharp collar stricture. Length of the two joints = 2 : 10,
breadth = 3 : 8. Cephalis subspherical, with very small pores and a small, pyramidal horn of
half the length. Thorax inflate, ovate ; in the uppermost part (beyond the collar stricture) with
a ring of six to nine very large roundish pores, which are twice to four times as broad as the
other "irregular, roundish pores. (The shell is seen in fig. 11 from the apical pole, in fig. lla
with the cephalis, in fig. 116 without it, exhibiting the four central collar pores of the cortinar
septum.) Mouth truncate, without prominent peristome.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 01 long, 0'08 broad.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

REPORT ON THE RADIOLARIA. 1301

8. Sethocyrtis cassis, Haeckel.

Cornutella cassis, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 38.
Cyrtocalpis cassis, Haeckel, 1862, Monogr. d. Eadiol., p. 287.

Shell pear-shaped, smooth, with obliterated collar stricture. Length of the two joints = 4 : 13,
breadth = 3 : 12. Cephalis ovate, with a conical horn of half the length. Thorax inflate, ovate,
with subregular, circular, quincuucial pores, twice to three times as broad as the bars. Mouth con-
stricted, truncate, two-thirds as broad as the thorax, without prominent peristome.

JMmensions. — Cephalis 0'04 long, 0'03 broad ; thorax 013 long, 012 broad.

Habitat. — Fossil in Tertiary rocks of Sicily (Caltanisetta).

Genus 576. Sethocorys,1 Haeckel, 1881, Prodromus, p. 430.

Definition. — Se t hocorida (vel Dicyrtida eradiata aperta) with ovate or sub-
cylindrical thorax, the mouth of which is constricted and prolonged into a ring-like
peristome. Cephalis with an apical horn.

The genus Sethocorys differs from the preceding Sethocyrtis, its ancestral form,
in the form of the constricted mouth, which is prolonged into a prominent, hyaline,
tubular, or annular peristome.

1. Sethocorys achillis, n. sp. (PL 62, fig. 8).

Shell rough, pear-shaped, with distinct collar stricture. Length of the two joints = 4 : 8,
breadth = 3:8. Cephalis ovate, with a stout pyramidal horn of half the length. Thorax nearly
spherical, with regular, circular, quincuncial pores of the same breadth as the cephalic pores.
Mouth constricted, half as broad as the thorax, with a broad, smooth, striated peristome.

Dimensions. — Cephalis 0'04 long, 0'03 broad ; thorax 0'08 long, 0'08 broad.

Habitat. — Cosmopolitan ; Mediterranean (Corfu), Atlantic, Indian, Pacific ; many stations, at
various depths.

2. Sethocorys patrocli, n. sp.

Shell thorny, pear-shaped, with slight collar stricture. Lengtli of the two joints = 4 : 12,
breadth = 3 : 10. Cephalis ovate, with a pyramidal horn of twice the length. Thorax ovate,
truncate at both poles, with regular, circular pores, twice as broad as the cephalic pores. Mouth
constricted, half as broad as the thorax, with a broad, smooth, prominent peristome.

Dimensions. — Cephalis 0'04 long, 0'03 broad ; thorax 012 long, 01 broad.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 3000 fathoms.

1 Ketliocorys = Sieve-helmet ; tijta, xo'ji/f.

1302 THE VOYAGE OF H.M.S. CHALLENGER.

3. Sethocorys armadillo, Haeckel.

Eucyrtidium armadillo, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss Berlin i> 70

Taf. ix. fig. 10.

^

Shell slenderly ovate, smooth, with deep collar stricture. Length of the two joints = 3 : 10,
breadth = 4: 6. Cephalis ovate, at the apex thorny, with a conical horn of the same length.'
Thorax smooth, ovate, truncate, with small, regular, circular pores, disposed in from twelve to fifteen
transverse rows of the same breadth as the cephalic pores. Mouth constricted, half as broad as
the thorax, with a broad, hyaline, prominent peristome.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax O'l long, 0'06 broad.

Habitat. — Fossil in Barbados.

4. Sethocorys odysseus, n. sp. (PL 62, fig. 10).

SheU ovate, smooth, with obliterated collar stricture. Length of the two joints = 2 : 9,
breadth = 4 : 8. Cephalis hemispherical, with a slender, conical horn of the same length. Thorax
nearly spherical, with regular, circular pores, of the same breadth as the cephalic pores, quincun-
cially disposed. Mouth constricted, only one-third as broad as the thorax, with a broad, hyaline,
prominent peristome.

Dimensions. — Cephalis 0'02 long, 0'04 broad ; thorax 0'09 long, 0'08 broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Sethocorys amphora, Haeckel.

Lophophama amphora, Stohr, 1880, Paheontogr., vol. xxvi. p. 99, Taf. iii. fig. 11.

Shell ovate, mouth with distinct collar stricture. Length of the two joints = 1:5,
breadth = 2:4. Cephalis hemispherical, with a short conical horn of half the length. Thorax
ovate, truncate, with small, regular, circular, quincuncial pores. Mouth constricted, half as broad
as the thorax, with a narrow, prominent, hyaline peristome.

Dimensions. — Cephalis 0-015 long, 0'03 broad ; thorax 0'07 long, 0'06 broad.

Habitat. — Fossil in Tertiary rocks of Sicily ; Grotte (Stohr).

6. Sethocorys ajacis, n. sp.

Shell slenderly ovate, smooth, without external collar stricture, but with an internal septum.
Length of the two joints = 1 : 3, breadth = 1:2. Cephalis conical, with a large pyramidal horn of
twice the length, and sometimes with a smaller accessory horn at its base ; its pores scarce,
irregular. Thorax ovate, truncate, hyaline, in the greater part without pores, in the smaller part

REPORT ON THE RADIOLARIA. 1303

with from two to four transverse rows of small, circular pores only. Mouth constricted, with a
large cylindrical, tubular, hyaline peristome, half as long as the shell.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 0'09 long, 0'07 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Genus 577. Lophophcena,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 54.

Definition. — Sethocorida (vel Dicyrtida eradiata aperta) with ovate or sub-
cylindrical thorax, the mouth of which is either truncate or constricted. Cephalis armed
with several large horns.

The genus Lophophcena differs from the nearly allied Sethocorys and Dictyocephalus
only in the armature of the large cephalis, which bears a group of large horns, often
arranged in a corona of radial spines. Sometimes these spines are connected by
anastomosing branches (like Arachnocorys).

Subgenus 1. Lophophcenula, Haeckel.

Definition. — Horns of the cephalis simple, free, radial spines, neither branched nor
connected.

1 . Lophophcena galea, Ehrenberg.

Lophophcena galea orci, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 245.
Lophophcena apiculata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78,

Taf. viii. fig. 11.
1 Cornutella spiniceps, Ehrenberg, 1875J Abbandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. ii. fig. 6.

Shell with slight collar stricture. Length of the two joints = 5:4, breadth = 5:6. Cephalis
subglobular, with numerous bristle-shaped, radial spines, about as long as its radius. Thorax about
the same size, truncate, conical, smooth, with wide open mouth. Pores in both joints of equal size,
small, regular, circular.

Dimensions. — Cephalis 005 long, 0'05 broad ; thorax O04 long, 0'06 broad.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms ; also fossil in Barbados.

2. Lophophcena radians, Ehrenberg.

Lophophcena radians, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78,

Taf. viii. fig. 9.
? Lophophcena lynx, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. viii. fig. 13.

Shell with slight collar stricture. Length of the two joints = 4:6, breadth = 4:5. Cephalis
subglobular, with numerous, stout, conical, radial spines, about as long as its diameter. Thorax

1 Lophophcena = Shell with a top-knot ; xo'fpoj,

1304 THE VOYAGE OF H.M.S. CHALLENGER.

of about the same size, subcylindrical, smooth, truncate, with wide open mouth. Pores in both
joints of equal size, small, regular, circular.

Dimensions. — Cephalis 0'04 long, O04 broad ; thorax 0'06 long, 0'05 broad.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific ; also fossil in Barbados.

3. Lophophcena liothorax, n. sp.

Shell with distinct collar stricture. Length of the two joints = 4:10, breadth = 4:8. Cephalis
subglobular, with large, circular, hexagonally-framed pores, and with numerous stout, conical, radial
spines, about as long as its diameter. Thorax twice as long, ovate, smooth, truncate, with little con-
stricted mouth, and with irregular, roundish pores, of very different sizes.

Dimensions. — Cephalis 0'04 long, 0'04 broad ; thorax O'l long, 0'08 broad.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

4. Lophophcena echinocephala, n. sp.

Shell with deep collar stricture. Length of the two joints = 4:8, breadth = 4:9. Cephalis
subglobular, of the same ' shape as in the preceding species. Thorax thorny, inflate, nearly
spherical, with a constricted mouth of half the breadth, and with irregular, roundish, double-
contoured pores.

Dimensions. — Cephalis 0'04 long, 0'04 broad ; thorax 0'08 long, 0'09 broad.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

Subgenus 2. Lophophcenoma, Haeckel.
Definition. — Horns of the cephalis connected by anastomosing branches.

5. Lophophcena circumtexta, Haeckel.

Lophophcena radians, var., Ehrenberg, 1875, Abhandl. cl. k. Akad. d. Wiss. Berlin, p. 78,
Taf. viil figs. 7, 8.

Shell with slight collar stricture. Length of the two joints = 4:5, breadth = 4:5. Cephalis
sub^lobular, with numerous conical, radial spines, about as long as its diameter, and at equal
distances from the surface, connected by anastomosing branches. Thorax nearly cylindrical, smooth,
little dilated towards the truncate, wide open mouth. Pores subregular, circular.

Dimensions. — Cephalis 0'04 long, 0'04 broad ; thorax 0'05 long, 0'05 broad.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms ; also fossil in
Barbados.

REPORT ON THE RADIOLARIA. 1305

Genus 578. Dictyocephalus,1 Ehrenberg, 1860, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 830.

Definition. — Sethocorida (vel Dicyrtida eradiata aperta) with ovate or sub-
cylindrical thorax, the mouth of which is more or less constricted, either truncate or with
a ring-like peristome. Cephalis rounded, without horn.

The genus Dictyocephalus has originated probably from Sethocorys by reduction and
loss of the apical horn. The mouth is more or less constricted, either simple, truncate
(Dictyocryphalus) , or provided with a prominent, broad, hyaline, annular peristome
(Dictyoprora).

Subgenus 1. Dictyoprora, Haeckel, 1881, Prodromus, p. 430.

Definition. — -Mouth of the thorax constricted, with a prominent, ring-like or tubular,
hyaline peristome.

1. Dictyocephalus amphora, n. sp. (PL 62, fig. 4).

Shell smooth, thick-walled, subovate, with slight collar stricture. Length of the two joints =
5 : 9, breadth = 6:8. Cephalis large, obtusely conical, with numerous oblique pore-canals. Thorax
inflate, with six to eight transverse rows of roundish pores, increasing in size towards the base.
Mouth constricted, one-third as broad as the thorax, with an internal diaphragm and a narrow
hyaline peristome.

Dimensions.— Cephalis 0'05 long, 0'06 broad; thorax 0'09 long, 0'08 broad.

Habitat. — Central Pacific, Stations 265 to 272, depth 2425 to 2925 fathoms.

2. Dictyocephalus urceolus, n. sp.

lEucyrtidium Mongolfieri, Bury, 1862, Polycystins of Barbados, pi. v. fig. 2.

Shell smooth, thick-walled, urceolate, with obliterated collar stricture. Length of the two joints
= 5:12, breadth = 4 : 10. Cephalis campanulate, with numerous oblique pore-canals. Thorax
inflate, with five or six transverse rows of roundish pores of equal size. Mouth constricted,
nearly half as broad as the thorax, with a broad hyaline peristome.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 0'12 long, 01 broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

1 Dictyocephalus = Latticed head ; 8/*Tfo», xi?)a?i».
(ZOOL. CHALL. EXP. — PART xu — 1886.) Rr 164

1306 THE VOYAGE OF H.M.S. CHALLENGER.

3. Dictyocephalus excellens, Haeckel.

Eucyrtidium excellens, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. x.

fig. 2.

Shell annulate, thick-walled, urceolate, with slight collar stricture. Length of the two
joints = 5 : 10, breadth = 4 : 7. Cephalis large, ovate-conical, with numerous oblique pore-
canals. Thorax ovate, with ten to twelve transverse rows of regular, roundish pores, which are
separated by prominent annular ribs. Mouth constricted, about half as broad as the thorax, with
a broad hyaline peristome.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 01 long, 0'07 broad.

Habitat. — Fossil in Barbados.

4. Dictyocephalus ocellatus, Haeckel.

Dictyocephalus ocellatus, Haeckel, 1862, Monogr. d. KadioL, p. 297.

1 Eucyrtidium ocellatum, Ehrenberg, 1861, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 299.

Shell smooth, thick- walled, with deep collar stricture. Length of the two joints = 3 : 9,
breadth = 4 : 7. Cephalis subspherical, with numerous oblique pore-canals. Thorax inflate,
campauulate, hyaline, only with three or four remote transverse rows of circular, double-contoured
pores of equal size. Mouth constricted, one-third as broad as the thorax, with a narrow hyaline
annular peristome.

Dimensions. — Cephalis 0'03 long, 0'04 broad; thorax 0'09 long, 0'07 broad.

Habitat. — North Atlantic, Greenland ; Fseroe Channel (Gulf Stream), John Murray.

5. Dictyocephalus crassiceps, Haeckel.

Eucyrtidium crassiceps, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi.

fig. 4.

Shell smooth, thick-walled, with sharp collar stricture. Length of the two joints = 4 : 6,
breadth = 3:4. Cephalis ovate, in the upper part with scattered pores, in the lower part' with
one transverse row of pores. Thorax hyaline, subcylindrical, only with four or five remote
transverse rows of small, circular pores. Mouth constricted, half as broad as the thorax, with a
short hyaline peristome.

Dimensions. — Cephalis 0'04 long, 0'03 broad ; thorax 0'06 long, 0'04 broad.

Habitat. — Fossil in Barbados.

6. Dictyocephalus australis, n. sp. (PL 62, fig. l).

Shell smooth, thick- walled, with slight collar stricture. Length of the two joints = 2 : 9-,
breadth = 3:6. Cephalis hemispherical, with few small pores. Thorax subcylindrical, with large,

REPORT ON THE RADIOLAR1A. 1307

roundish, double-contoured pores, irregularly disposed. Mouth constricted, two-thirds as broad as
the thorax, with a broad, hyaline peristome.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'09 long, 0'06 broad.

Habitat. — East coast of Australia, Station 164, surface.

7. Dictyocephalus mediterraneus, n. sp. (PL 62, fig. 2).

Shell rough, thin-walled, with slight collar stricture. Length of the two joints = 3 : 10,
breadth = 4 : 8. Cephalis hemispherical, with small, circular pores. Thorax ovate, truncate, with
much larger circular pores of different sizes and thin bars between them. Mouth little constricted,
two-thirds as broad as the thorax, with a narrow, hyaline peristome.

Dimensions. — Cephalis 0'03 long, 0-04 broad ; thorax 01 long, 0'08 broad.

Habitat. — Mediterranean, Smyrna (Haeckel), surface.

8. Dictyocephalus papillosus, Haeckel.

Eucyrtidium papillosum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293, Taf. vii.

fig. 10.

Shell thin-walled, papillate, with obliterated collar stricture. Length of the two joints = 2:7,
breadth = 3:5. Cephalis hemispherical, with small, circular pores. Thorax slenderly ovate, with
larger, subregular, circular pores, separated by oblique series of conical papillae. Mouth with a
broad, hyaline peristome (the " third articulus " of Ehrenberg), separated by a stricture from the little
broader thorax.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'07 long, 0'05 broad.

Habitat. — Western Tropical Pacific (Philippine Sea), depth 3300 fathoms.

9. Dictyocephalus tabulatus, n. sp.

Shell thin-walled, papillate, with obliterated collar stricture. Length of the two joints = 2:10,
breadth = 3 : 7. Cephalis hemispherical, with small, circular pores. Thorax slenderly ovate,
truncate, with large, subregular, circular, hexagonally-framed pores. Mouth little constricted
nearly as broad as the thorax, with a broad, hyaline peristome.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 01 long, 0'07 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

10. Dictyocephalus reticulum, Haeckel.

Dictyocephalus reticulum, Haeckel, 1862, Monogr. d. Radiol., p. 297.

Eucyrtidium reticulum, Ehrenberg, 1861, Monatsber. d. k. preuss. Akad. d. "Wiss. Berlin, p. 300.

Shell thin-walled, smooth, with deep collar stricture. Length of the two joints = 2 : 8,
breadth = 3 : 5. Cephalis subspherical, with small, circular pores. Thorax campanulate, with

1308 THE VOYAGE OF H.M.S. CHALLENGER.

transverse rows of alternating square pores. Mouth little constricted, nearly as long as the thorax,
with a narrow, prominent peristome.

Dimensions. — Cephalis 0'02 long, 0'03 broad ; thorax 0'08 long, O05 broad.

Habitat. — Arctic Ocean, Greenland (Schaffner) ; Iceland (Krabbe).

11. Dictyocephalus ampulla, n. sp.

Shell thin- walled, smooth, with slight collar stricture. Length of the two joints = 1:4,
breadth = 1 : 3. Cephalis subspherical, without pores, hyaline. Thorax inflate, subspherical,
with scarce and small, widely-scattered, circular pores. Mouth constricted, only one-third as
broad as the thorax, with a narrow, prominent peristome.

Dimensions. — Cephalis 0'02 long, 0'02 broad ; thorax 0'08 long, 0'07 broad.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 2. Dictyocryphalus, Haeckel, 1881, Prodromus, p. 430.

Definition. — Mouth of the thorax flat or truncate, without prominent ring-like
peristome.

12. Dictyocephalus obtusus, Ehrenberg.

Dictyocephalus obtusus, Ehrenberg, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 830.
Lophophcena obtusa, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 40.

Cornutella obtusa, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 877.
Dictyocephalus obtusus, Haeckel, 1862, Monogr. d. Radiol., p. 296.

Shell smooth, thick-walled, with distinct collar stricture. Length of the two joints = 5:6
breadth = 4:5. Cephalis ovate, little smaller than the subcylindrical thorax. Pores subregular,
circular, of little different sizes. Mouth truncate, without ring-like peristome.

Dimensions. — Cephalis 0'05 long, 0'04 broad ; thorax 0'06 long, O05 broad.

Habitat. — Fossil in Tertiary rocks of Sicily (Caltanisetta), Grotte, &c.

13. Dictyocephalus globiceps, n. sp. (PL 62, fig. 7).

Shell rough, thin-walled, with distinct collar stricture. Length of the two joints = 6:8,
breadth = 6:7. Cephalis subspherical, large, with circular, double-contoured pores. Thorax
cylindrical, with irregular, roundish pores, the size of which, like the thickness of the wall,
decreases gradually towards the truncate mouth, which has no ring-like peristome.

Dimensions. — Cephalis O06 long, 0'06 broad ; thorax, 0'08 long, 0'07 broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

EEPOBT ON THE RADIOLARIA. 1309

14. Dictyocephalus cavea, n. sp.

Shell rough, thin-walled, with slight collar stricture. Length of the two joints = 3:10 =
breadth = 5:7. Cephalis hemispherical, thorny, with numerous regular, circular pores. Thorax
subcylindrical, with very large, circular, hexagonally-framed pores (hi nine longitudinal alternating
rows), three to five times as broad as the cephalic pores. Mouth truncate, wide open, without
ring-like peristome.

Dimensions. — Cephalis 0'06 long, O'l broad ; thorax O2 long, 0'14 broad.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

15. Dictyocephalus capita, Ehrenberg.

Dictyocephahis capita, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 289,

Taf. vii. fig. 24.

Shell smooth, thin-walled, with sharp collar stricture. Length of the two joints = 7:9,
breadth = 6:8. Cephalis ovate, with numerous irregular, roundish, densely - crowded pores.
Thorax ovate, with very few widely-scattered, irregular, roundish pores (broken off in Ehrenberg's
figure). Mouth truncate, little constricted, without ring-like peristome.

Dimensions. — Cephalis 0'07 long, 0'06 broad ; thorax 0'09 long, 0-08 broad.

Habitat. — Western Tropical Pacific (Philippine Sea) Station 206, depth 2100 fathoms.

16. Dictyocephalus hispidus, Ehrenberg.

Dictyocephalus hispidus, Ehrenberg, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin ; Abhandl.

d. k. Akad. d. Wiss. Berlin, 1872, p. 289, Taf. v. fig. 18.

Shell rough, thin-walled, with deep collar stricture. Length of the two joints = 3:4,
breadth = 3:5. Cephalis subspherical, spiny, with the same irregular, roundish pores as the
funnel-shaped or nearly ovate thorax. Mouth truncate, little narrower than the thorax, without
ring-like peristome.

Dimensions. — Cephalis 0'03 long, 0'03 broad ; thorax 0'04 long, 0'05 broad.

Habitat. — Tropical Atlantic, Mexican Gulf (Ehrenberg) ; Station 338, depth 1990 fathoms.

Subfamily 2. SETHOCAPSIDA, Haeckel, 1881, Prodromus, p. 433.

Definition. — Sethocyrtida with the basal mouth of the shell fenestrated (vel
Dicyrtida eradiata clausa).

1310 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 579. Sethocapsa,1 Haeckel, 1881, Prodromus, p. 433 (sensu emendate).

Definition. — S ethocapsida (vel Dicyrtida eradiata clausa) with a free cephali
bearing an apical horn.

The genus Sethocapsa and the two following genera represent together the small
subfamily of Sethocapsida, or those Dicyrtida in which the mouth of the thorax is
closed, and no radial apophyses are present. Sethocapsa may be derived either from
Lithopera by loss of the three radial rods, or from Sethocyrtis by closure of the mouth.

1. Sethocapsa pyriformis, n. sp. (PI. 57, fig. 2).

Shell rough, pear-shaped, with slight collar stricture. Length of the two joints = 3:10,
breadth = 3:8. Cephalis subspherieal, with numerous small pores, and a short pyramidal or
conical horn of half the length. Thorax ovate, with subregular, circular, quincuncial pores.

Dimensions. — Cephalis 0'03 diameter, thorax 01 long, 0'08 broad.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 3000 fathoms.

2. Sethocapsa lagena, Haeckel.

Lithopera lagena, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii. fig. 4.

Shell smooth, pear-shaped, with sharp colkr stricture. Length of the two joints = 3:8,
breadth = 3:6. Cephalis pear-shaped, with few scarce pores, and a small conical horn of half the
length. Thorax pear-shaped, with irregular, roundish pores. This species differs from the similar
Lithopera lagena almost only in the complete absence of the three internal radial collar beams
inside the thorax, and may be derived from it by their retrograde metamorphosis.

Dimensions. — Cephalis 0'03 diameter, thorax 0'08 long, 0'06 broad.

Habitat. — Fossil in Barbados.

3. Sethocapsa macroceros, n. sp.

Shell smooth, pear-shaped, with slight collar stricture. Length of the two joints = 2 : 11,
breadth = 2 : 9. Cephalis subspherieal, with small circular pores, and a very large, straight, pyra-
midal horn, of about the same length as the shell. Thorax ovate, with large, irregular, roundish pores,
which are surrounded by polygonal frames.

Dimensions. — Cephalis 0'02 diameter, thorax Oil long, 0'09 broad.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

1 Sethocapsa = Sieve-capsule ; uijfc, x.ii\f,».

REPORT ON THE RADIOLARIA. 1311

4. Sethocapsa nidus, Haeckel.

Lithapera nidus pendulus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii.

fig. 7.

Shell smooth, pear-shaped, with distinct collar stricture. Length of the two joints = 3:6,
breadth = 3:5. Cephalis subspherical, with a large, straight, pyramidal horn of twice the length,
and scarce small pores. Thorax ovate, also with very small and scarce pores.

Dimensions. — Cephalis 0'03 diameter, thorax 0'06 long, 0'05 broad.

Habitat. — Fossil in Barbados.

5. Sethocapsa bulla, n. sp.

Shell spiny, with slight collar stricture. Length of the two joints = 3 : 12, breadth = 4 : 12.
Cephalis hemispherical, with small, scarce pores, and a conical horn of the same length. Thorax
nearly spherical, with large, subregular, circular, quincuncial pores, twice as broad as the bars.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 012 long, 012 broad.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; fossil in Barbados.

6. Sethocapsa ampulla, n. sp.

Shell papillate, with slight collar stricture. Length of the two joints = 1:5, breadth = 1:5.
Cephalis hemispherical, hyaline, without pores, with a large pyramidal horn of twice the length.
Thorax nearly spherical, with large, irregular, roundish, lobulated pores.

Dimensions. — Cephalis 0'03 long, 0'04 broad ; thorax 015 long, 015 broad.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

7. Sethocapsa staurocephala, Haeckel.

1 Lithopera oxystauros, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii.

fig. 6.

ILithopera amblystauros, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iii.

fig- 5.

Shell smooth, with slight collar stricture. Length of the two joints =3 : 4, breadth = 3 : 4.
Cephalis large, ovate, with a conical horn of the same length, small scarce pores, and an internal
frontal septum, composed of two crossed beams, a vertical and a horizontal Thorax little larger
than the cephalis, ovate, with irregular, small and scarce pores. (The two figures of Ehrenberg are
either incomplete — in Lithopera amblystauros, the cephalic horn, and in Lithopera oxystauros, the
basal part of the thorax, being broken off — or they belong to different Botryodea).

Dimenswns.^Gephalis 0'03 diameter, thorax 0'04 diameter.

Habitat. — Fossil in Barbados.

1312 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 580. Dicolocapsa,1 Haeckel, 1881, Prodromus, p. 433 (sensu emendate).

Definition. — S ethocapsida (vel Dicyrtida eradiata clausa) with a free cephalis,
without apical horn.

The genus Dicolocapsa differs from the preceding Sethocapsa in the loss of the
apical horn, and therefore bears to it the same relation that Dictyocephalus does to
Sethocyrtis.

1. Dicolocapsa microcephala, n. sp. (PL 57, fig. 1).

Shell smooth, thin-walled, with distinct collar stricture. Cephalis small, subspherical, with
small, crowded pores. Length of the two joints = 1:3, breadth = 1 : 3. Thorax also nearly spherical,
three times as large as the cephalis, with small, irregularly scattered, circular pores, and much
broader bars.

Dimensions. — Cephalis 0'03 diameter, thorax 0'09 diameter.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Dicolocapsa megacephala, n. sp.

Shell smooth, thin-walled, with sharp collar stricture. Cephalis large, conical, obtuse. Length
of the two joints = 5:9, breadth = 6 : 8. Thorax ovate, truncate, with hemispherical base. Pores
of both joints equal, subregular, circular, about as broad as the bars.

Dimensions. — Cephalis 0'05 long, O06 broad ; thorax 0-09 long, O'OS broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Dicolocapsa platycephala, n. sp.

Shell papillate, thick-walled, with slight collar stricture. Cephalis flat, hemispherical, hyaline,
without pores (or with few small pores). Length of the two joints = 2 : 11, breadth = 4 : 9. Thorax
ovate, with small, regular, circular pores, half as broad as the bars.

Dimensions.^Cephalis 0-02 long, 0'04 broad ; thorax Oil long, 0'09 broad.

Habitat. — Fossil in Barbados.

Genus 581. Cryptocapsa,'2 Haeckel, 1881, Prodromus, p. 433.

Definition. — S ethocapsida (vel Dicyrtida eradiata clausa) with a cephalis
hidden in the thorax, without apical horn.

1 Dicolocapsa = Two-jointed capsule ; 8/xaXof, xii-^a.

2 Cryptocapsa = Hidden capsule ; xyjvro;, xxt^a.

REPORT ON THE RADIOLARIA. 1313

The genus Cryptocapsa differs from the preceding Dicolocapsa, its ancestral form,
in the peculiar shape of the cephalis, which is nearly perfectly enclosed in the upper part
of the inflated thorax. It has, therefore, to the latter the same relation as Carpocanium
bears to Anthocyrtis.

1. Cryptocapsa bacca, n. sp.

Cephalis spherical, with small circular pores enclosed in the upper part of the thorax, which is
ovate, smooth, and exhibits regular, circular pores, about as broad as the bars.
Dimensions. — Cephalis 0'03 diameter, thorax 0'15 long, 0'12 broad.
Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Cryptocapsa pila, n. sp.

Cephalis spherical, with few small pores,, enclosed in the upper part of the thorax, which is
pear-shaped, spiny, and exhibits subregular, hexagonal pores, three times as broad as the bars.
From each hexagon corner a small thorn arises.

Dimensions. — Cephalis 0'04 diameter, thorax 0'25 long, 0'17 broad.

Habitat. — Central Pacific, Station 269, depth 2900 fathoms.

Section III. TEICYETIDA, Haeckel, 1881, Prodromus, p. 426, 434.

Definition. — C yrtoidea trithalamia, with three-jointed shell, composed of cephalis,
thorax, and abdomen, with two separating transverse constrictions, an upper collar, and a
lower lumbar constriction.

Synopsis of the Families and Subfamilies of Tricyrtida.

Family LXV. ( Mouth open, . . . Theopilida.

Podocyrtida.
Three radial apophyses. ( Mouth closed, . Theoperida.

Family LXVI. ( Mouth open, . . Theophormida.

Phormocyrtida.
Numerous radial apophyses. ( Mouth closed, . Theophaenida.

Family LXVII. ( Mouth open, . . . Theocorida.

Theocyrtida.
No radial apophyses. ( Mouth closed, . Theocapsida.

(ZOOL. CHALL. EXP. — PAKT XL. — 1886.) Rr 165

1314 THE VOYAGE OF H.M.S. CHALLENGER.

Family LXV. PODOCYBTIDA, n. fern. (PI. 67, 68, 71-73).

Theopilida et Theoperida, Haeckel, 1881, Prodromus, p. 435, 436.

Definition. — Tricyrtida triradiata. (C yrtoi dea with a three-jointed shell,
divided by two transverse constrictions into cephalis, thorax, and abdomen, and bearing
three radial apophyses.)

The family Podocyrtida, composed of the Theopilida and Theoperida of my
Prodromus, comprises those Cyrtoidea in which the lattice-shell is three-jointed and
triradial, bearing three external apophyses. The two subfamilies differ in the shape of
the basal mouth, which in the Theopilida is a simple wide opening, in the Theoperida
closed by a lattice-plate. The latter are derived from the former by development of this
closing plate. The phylogenetic origin of the Podocyrtida may be found in the
Tripocyrtida, from which they are derived by development of an abdomen. But there
are also some forms, which may be derived directly from the Plectoidea, and the
origin of some other forms seems to be doubtful.

The Podocyrtida represent one of the largest groups of Cyrtoidea, very rich
in numerous species, which are partly very common and widely distributed. A large
number of living and fossil species has already been described and figured by Ehrenberg,
(1872, 1879, loc. cit.). These mainly belong to his genera Podocyrtis, Pterocanium,
Rhopalocanium, Lithornithium, &c., and many of them are very characteristic and
common forms, in which the triradial structure of the three-jointed shell is visible at
first view. We distinguish here twenty genera and one hundred and fifty species.
The majority have a shell with a simple wide open mouth (Theopilida, fourteen genera
and one hundred and eighteen species), in the minority the mouth is closed by lattice-
work (Theoperida, six genera and thirty-two species).

The three joints of the shell have in the majority of Podocyrtida such a proportion
that the cephalis is the smallest, the abdomen the largest, and the thorax between them
intermediate in size. The cephalis bears almost constantly an apical horn ; this is
rarely reduced or lost ; sometimes two or more horns are developed. The three radial
apophyses arise originally from the base of the cephalis, and may from this point run
along the shell-wall embedded in the lattice-plate of the thorax and the abdomen. They
leave the latter at very different points, and form either lateral wings or terminal feet,
sometimes both together. They are either solid or latticed, sometimes also branched,
and of very various shape. Often only the three terminal feet surrounding the mouth
have remained, whilst the ribs have disappeared.

Many species of this large family are very variable and connected with other
different species by numerous transitional forms ; the distinction of the genera described
is also often very difficult.

REPORT ON THE RADIOLARIA.

1315

of the Genera of Podocyrtida.

1

Wings arising from

the thorax,

Three wings of
the thorax •<

Three ribs enclosed
in the wall of the

solid.

thorax, .

,

No free ex-

ternal appen-

Wings arising free

dages on the

from the collar

abdomen.

stricture,

A. Three free

' Wings not prolonged

I. Subfamily
Theopilida.
(Podocyrtida

limbs or wings
on the thorax
(partly also
on the abdo-

Three wings of 1 ^to the cephalis,
the thorax J ,,,..

latticed ' WlDgs Prolonged
into the cephalis,

aperta.)

men).

-

Three ribs pro-

Ribs and feet solid,

Terminal mouth

longed into ^

of the shell a

three termi- "*

liibs and feet lat-

simple wide
opening.

Free appen-
dages on the <
abdomen.

nal feet.

Three free
wiugs on the

ticed,

' Wings and feet
solid, .

thorax. Nu- •>

merous termi-

Wings and feet

.

nal feet.

latticed, .

' Abdomen with three ribs and three feet,

B. Free appen-
dages not on
the thorax, .
only on the
abdomen.

Abdomen without lateral ribs,
with three terminal feet.

' Three feet solid,
simple, .

Three feet solid,
ramified,

Three feet latticed,

( Wings solid,
Three lateral wings onlv on the thorax. . 1

II. Subfamily

{

Wings latticed,

Theoperida.

(Podocyrtida

Three lateral wings beginning from the thorax

and prolonged into

clausa.)

the abdomen, ....

.

Terminal mouth
of the shell
closed by a
lattice-plate.

Three wings
only on the '
abdomen.

fNo horn on the
Shellspindle-shaped,with three I basal pole, .
lateral wings on the abdo--j
men. | Basal pole of the
[ shell with a horn,

Shell three-sided pyramidal, with three terminal-

l feet on the basal corners, .

.

582. Pterocorys.

583. Theopilium.

584. Coroccdyptra.

585. Dictyoceras.

586. Pteropilium.

587. Theopodium.

538. Pterocanium.

589. Pterocodon.

590. Dictyocodon.

591. Pleuropodium.

592. Podocyrtis.

593. Thyrsocyrtis.

594. Dictyopodium.

595. Lithornithium.

596. Sethornithium.

597. Theopera.

598. Rhopalocanium.

599. Rhopalatractus.

600. Lithochytris.

Subfamily 1. THEOPILIDA, Haeckel, Prodromus, p. 435.

Definition. — Podocyrtida with the terminal mouth of the shell open (vel
Tricyrtida triradiata aperta).

1316 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 582. Pterocorys,1 Haeckel, 1881, Prodromus, p. 435.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three simple,
free lateral wings arising from the sides of the thorax.

The genus Pterocorys, comprising numerous and some very common species, may
be one of the oldest and most primitive Theopilida, and is perhaps the common
ancestral form of all Tricyrtida. It exhibits three free lateral wings, arising from the
sides of the thorax, like Lithomelissa among the Dicyrtida, and may be derived directly
from this genus by development of an abdomen. The latter is commonly cylindrical or
ovate, with a wide open mouth, whilst the thorax is either campanulate or three- sided
and pyramidal.

Subgenus 1. Pterocyrtidium, Butschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi.

p. 531.

Definition. — Horn of the cephalis simple. Abdomen not prolonged into a narrow
tube.

1. Pterocorys campanula, n. sp. (PI. 71, fig. 3).

Shell campanulate, with two distinct strictures. Length of the three joints = 2:3:2,
breadth = 2 : 4 : 6. Cephalis subovate, with a pyramidal horn of the same length. Thorax sub-
conical, in the middle zone with three conical, horizontal wings, shorter than the cephalis, from
which three thin ribs are decurrent to the mouth. Abdomen short and much dilated, with wide,
truncate mouth. Pores nearly equal, small, subregular, circular.

Dimensions. — Length of the three joints, a 004, b O06, c 0'04 ; breadth, a 0:03, b 0'08, c 012.

Habitat. — Central Pacific, Stations 266 to 274, surface.

2. Pterocorys carinata, Haeckel.

Eucyrtidium carinatum, Haeckel, 1862, Monogr. d. Kadiol., p. 322, Taf. vii. figs. 4-7.

Shell subovate, with two distinct strictures. Length of the three joints = 1 : 2 : 3,
breadth = 1:3:4. Cephalis ovate, with a pyramidal horn of twice the length. Thorax cam-
panulate, with three decurrent crests, from which in the lower part three small conical wings arise,
shorter than the cephalis. Abdomen barrel-shaped, inflated, with wide, truncate mouth. Pores
everywhere equal, small, regular, circular, quincuncial.

Dimensions. — Length of the three joints, a 0'25, b 0'05, c 0'075 ; breadth, a 0'25, b 0'09, c 01.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific ; many stations, surface.

1 Pterocorys = Helmet with wings ; irrtfov, xo'jv;.

REPORT ON THE RADIOLARIA. 1317

3. Pterocorys sdbce, Haeckel.

Pterocanium sabce, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 299, Taf. x. fig. 17.

Shell campanulate or subconical, with two sharp strictures. Length of the three joints = 1:3:4,
breadth = 1:4:5. Cephalis subspherical, with a conical horn of the same length. Thorax sub-
conical, in the lower third with three small, conical, little curved wings, shorter than the cephalis.
Abdomen dilated towards the wide, truncate mouth. Pores subregular, circular, gradually increasing
in size from the collar towards the mouth.

Dimensions. — Length of the three joints, a 0'025, b 0'06, c 0'08 ; breadth, a 0'02, b 0'08,
c 0-09. •

Habitat. — Indian Ocean, Zanzibar, 2200 fathoms (Pullen).

4. Pterocorys columba, n. sp. (PI. 71, fig. 2).

Shell subovate, with two deep strictures. Length of the three joints = 2:5:4, breadth = 3:7:7.
Cephalis hemispherical, with a curved conical horn of the same length. Thorax inflate, in the
middle zone with three pyramidal downwardly divergent wings of nearly the same length.
Abdomen short, inflate, little constricted towards the wide, truncate mouth. Pores all nearly
equal, subregular, circular.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'04 ; breadth, a 0'03, b 0'07, c 0'07.

Habitat. — North Pacific, Station 237, surface.

5. Pterocorys falcifera, Haeckel.

Pterocanium falciferum, Stohr, 1880, Palseontogr., vol. xxvi. p. 107, Taf. iv. fig. 15.
? Pterocanium bibrachiatum, Stohr, 1880, Palseontogr., vol. xxvi. p. 106, Taf. iv. fig. 14.

Shell subovate, with two distinct strictures. Length of the three joints = 2 : 6 : 5
breadth = 3 : 9 : 10. Cephalis subspherical, with a conical horn of the same length. Thorax
hemispherical, thick-walled, rough, with three stout triangular wings, which are about as long as
the shell, and curved downwards, with upper convexity. Abdomen ovate, cylindrical, with wide,
truncate mouth. Pores irregular, roundish, large and small intermingled ; at the base of the
abdomen (below the lumbar girdle) a circle of somewhat oblong, quadrangular pores.

Dimensions. — Length of the three joints, a 0"02, b 0'06, c 0'05 ; breadth, a 0'03, b 0'09, c 01.

Habitat. — Fossil in Tertiary rocks of Sicily, Grotte (Stohr) ; Caltanisetta (Haeckel).

6. Pterocorys aquila, n. sp. (PI. 71, fig. 5).

Shell ovate, with two deep strictures. Length of the three joints = 1:4:4, breadth = 1:8:6.
Cephalis hemispherical, with a slender curved horn of three times the length. Thorax hemi-
spherical, campanulate, spiny, prolonged above the lumbar girdle into three stout, three-sided prismatic

1318 THE VOYAGE OF H.M.S. CHALLENGER.

wings, which are longer than the shell, fenestrated at the base, and S-shaped, curved. Abdomen
barrel-shaped, with wide, truncate mouth. Pores irregular, roundish, of very different sizes.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'08 ; breadth, a 0'03, b 016, c 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

7. Pterocorys hirundo, n. sp. (PI. 71, fig. 4).

Shell slender, ovate, with two deep strictures. Length of the three joints = 1:4:4,
breadth = 2 : 5 : 5. Cephalis hemispherical, with a large pyramidal horn longer than the half
shell. Thorax conical, spiny, prolonged above the lumbar girdle into three slender, triangular,
prismatic wings, which are about as long as the shell, and slightly curved downwards, with lower
convexity. Abdomen inflated, with wide, truncate mouth, Pores irregular, roundish, of very
different sizes.

Dimensions. — Length of the three joints, a 0'03, b 0'08, c 0'08 ; breadth, a 0'04, b 01, c 01.

Habitat. — Central Pacific, Station 272, depth '2600 fathoms.

8. Pterocorys barbadensis, Haeckel.

Pterocanium barbadense, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82,

Taf. xvii. fig. 6.
Pterocyrtidium barbadense, Biitschli, 1882, Zeitschr. f. wiss. Zool., Bd. xxxvi., Taf. xxxiii.

fig. 29, a, b.

Shell slender, smooth, with two slight strictures. Length of the three joints =1 : 3 : 4,
breadth = 2:4:4. Cephalis hemispherical, with a stout pyramidal horn of twice the length.
Thorax campanulate-conical, in the lower half with three divergent, angular wings, which are
slightly curved downwards, and as long as the thorax. Abdomen cylindrical, with wide, truncate
mouth. Pores small, subregular, circular.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'07 ; breadth, a 0'04 ; b 0'07, c 0'07.

Habitat. — Fossil in Barbados.

9. Pterocorys apis, Haeckel.

Pterocodon apis, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xix. fig. 3.

Shell slender, smooth, with two distinct strictures. Length of the three joints = 1:2:6,
breadth = 2:3:4. Cephali s hemispherical, with a curved, conical horn of three times the length.
Thorax very small, with three nearly horizontal, conical wings, which are slightly curved down-
wards, and twice as long as the thorax. Abdomen cylindrical, three times as long as the thorax,
with wide, truncate mouth. Pores small, subregular, circular. Differs from all other species
in the very small size of the thorax ; the abdomen is broken off in Ehrenberg's figure.

Dimensions. — Length of the three joints, a 015, b 0'02, c 0'06 ; breadth, a 0'02, b 0'03, c 0'04.

Habitat. — Cosmopolitan ; Atlantic, Pacific, many stations ; also fossil in Barbados.

REPORT ON THE RADIOLARIA. 1319

10. Pterocorys melitta, Haeckel.

Rhopalocanium ornatum, Bury, 1862, Polycystins of Barbados, Taf. vL fig. 4.

Shell slender, smooth, with two deep strictures. Length of the three joints = 1:1:3,
breadth = 1:2:2. Cephalis subspherical, with a pyramidal horn of twice the length. Thorax broad
and short, loaf-shaped, with three conical wings, which are horizontally expanded, and half as
long as the shell. Abdomen cylindrical, with wide, truncate mouth. Pores small, subregular,
circular.

Dimensions. — Length of the three joints, a 0'025, b Q'03, c 0'09 ; breadth, a 0'03, b 0'06, c 0'06.

Habitat. — Fossil in Barbados.

11. Pterocorys turgida, Haeckel.

Lychnocanium turgidum, Ehrenberg, 1885, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80,

Taf. vii. fig. 6.

Shell thick-walled, pear-shaped, smooth, with sharp collar stricture. The lumbar stricture is
not distinct externally, but is represented by a broad, internal, annular septum. Length of the three
joints = 1 : 6 : 3, breadth = 2 : 7 : 6. Cephalis hemispherical, with a stout pyramidal horn of the
same length. Thorax and abdomen together pear-shaped, inflated. Immediately above the lumbar
stricture three stout, conical, lateral wings, as long as the cephalis, arise. Mouth very small,
about as broad as the cephalis.

Dimensions. — Length of the three joints, a 0'02, b 012, c 0'06 ; breadth, a 0'03, b 013, c 012.

Habitat. — Fossil in Barbados.

Subgenus 2. Pterosyringium, Haeckel.

Definition. — Horn of the cephalis simple. Abdomen prolonged into a narrow
cylindrical tube.

12. Pterocorys tubulosa, n. sp. (PI. 68, fig. 6).

Pterosyringium tubulosum, Haeckel, 1879, Atlas, loc. cit.

Shell thick-walled, rough, with two slight strictures. Length of the three joints = 1 : 4 : 4,
breadth = 1:3:1. Cephalis hemispherical, with a conical horn of the same length. Thorax
ovate, in the upper half with three ribs, arising into short, triangular, slightly prominent wings.
Abdomen prolonged into a cylindrical, narrow tube of the same length as the thorax. Terminal
mouth very narrow. Pores subregular, circular.

Dimensions. — Length of the three joints, a 0'03, I 012, c 012 ; breadth, a 0'03, b 0'09, c 0'03.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

1320 THE VOYAGE OF H.M.S. CHALLENGER.

13. Pterocorys pipetta, n. sp.

Shell thin-walled, smooth, with two slight strictures. Length of the three joints =1:6:3,
breadth = 1:3:1. Cephalis ovate, with a conical horn of twice the length. Thorax ovate, in the
middle zone with three conical wings of the same length, curved slightly downwards (like those of
Pterocorys columba, PL 71, fig. 2). Abdomen constricted into a cylindrical tube half as long as the
thorax, with narrow mouth. Pores subregular, circular.

^mew*«»w— Length of the three joints, a 0'02, I 012, c 0'06 ; breadth, a 0'02, b 0'06, c 002.

Habitat. — Tropical Atlantic, Station '347, depth 2250 fathoms.

Subgenus 3. Pterocorythium, Haeckel.

Definition. — Horn of the cephalis. double or multiple. Abdomen not prolonged into
a narrow tube.

14. Pterocorys rhinoceros, n. sp. (PI. 71, fig. 1).

Shell very delicate and thin-walled, with two sharp strictures. Length of the three joints =
2 : 10 : 3, breadth, 3:11:9. Cephalis obtuse, conical, with two divergent, conical horns of equal
length. Thorax triangular, pyramidal ; from its three edges there arise on the middle joint three
conical descending wings (little larger than the horns), and from the base of each wing descend two
divergent crests, forming at the sides of the pyramid three rounded lobes. Abdomen short,
cylindrical, with wide, truncate mouth. Network of the whole shell very delicate, with very small
and numerous, regular, circular, hexagonally-framed pores.

Dimensions. — Length of the three joints, a 0'02, b 01, c 0'03 ; breadth, a 0'03, b Oil, c 0'09.

Habitat. — -Central Pacific, Stations 270 to 274, surface, and in various depths.

15. Pterocorys prismatica, n. sp.

Shell very delicate and thin-walled throughout, with fine fenestration similar to that of the
preceding species, but differing from it in the form of the abdomen, which is much larger, three-
sided and prismatic ; three edges of the prism decurrent from the bases of the three short wings.
Length of the three joints = 1:4:5, breadth = 2:6:6. No lobes at the thorax. Mouth wide
open, truncate, triangular.

Dimensions.— Length of the three joints, a 0'02, b 0'08, c 01 ; breadth, a 0'04, b 012, c 012.

Habitat. — South Pacific, Station 288, surface. .

16. Pterocorys tricornis, n. sp.

Shell spiny, with two deep strictures. Length of the three joints = 1:5:3, breadth = 1:7:5.
Cephalis subspherical, with three stout, pyramidal, divergent horns, which are three times as long,

REPORT ON THE RADIOLARIA. 1321

and bear three serrated edges. Thorax three-sided pyramidal, spiny ; its three edges prolonged
at the girdle into three stout, triangular, prismatic wings of the same length, little curved.
Abdomen short, cylindrical, with wide open, truncate mouth. Pores irregular, polygonal, roundish.

Dimensions. — Length of the three joints, a 0'02, b 01, c 0'06 ; breadth, a 0'03, b 014, c 01.

Habitat. — North Pacific, Station 244, surface.

17. Pterocorys zittelii, Haeckel.

Pterocyrtidium zittelii, Biitsclili, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. pp. 531, 540, Taf.

xxxiii. figs. 28, a, I).

Shell thin-walled, rough, with two slight strictures. Length of the three joints = 2:5:7,
breadth = 3:5:5. Cephalis hemispherical, armed with a very large, prismatic, vertical horn, which
is half as long as the shell, and at its base surrounded by several (three to five) shorter, upwardly
diverging horns. Thorax campauulate, in the upper half with three short, downwardly diverging,
conical wings. Abdomen subcylindrical, with wide, truncate mouth. Pores small, subregular,
circular.

Dimensions. — Length of the three joints, a 0'02, b O'Oo, c 0'07 ; breadth, a 0'03, b 0'05, c 0'05.

Habitat. — -Fossil in Barbados.

18. Pterocorys macroptera, n. sp.

Shell thin-walled, smooth, with two slight strictures. Length of the three joints =1:3:2,
breadth =1:4:3. Cephalis hemispherical, armed with two larger and six to eight smaller, conical,
divergent horns of different lengths. Thorax three-sided pyramidal ; its three edges prolonged into
three very large diverging wings, which are slender, three-sided, prismatic, and nearly twice as long
as the shell. Abdomen short, cylindrical, with wide, truncate mouth. Pores irregular, roundish,
in the middle part of the shell (on both sides of the girdle) much larger than in the upper and
lower part.

Dimensions. — Length of the three joints, a 0'03, b 0'09, c O'OG ; breadth, a 0'04, b 012, c 01.

Habitat. — South Atlantic, Station 335, surface.

Genus 583. TJieopilium,1 Haeckel, 1881, Prodromus, p. 435.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three lateral ribs
enclosed in the wall of the thorax, without free lateral or terminal appendages.

The genus Theopilium differs from all the other Theopilida in the absence of free
external appendages ; it has neither lateral wings nor terminal feet, but three divergent
ribs are enclosed in the wall of the thorax. It agrees in this character with the Dicyrtid
Lamprodiscus, and may be derived directly from this by development of an abdomen.

1 Theoj)Uium=T)i\'ine hat; Qios, irfatoy.
CHALL. EXP.— PART XL.— 1886.) Rr 166

1322 THE VOYAGE OF H.M.S. CHALLENGER.

1. Theopilium tricostatum, n. sp. (PI. 70, fig. 6).

Shell flatly conical, smooth. Length of the three joints = 1:4:2, breadth = 2:6:10. Cephalis
subspherical, with a thin oblique horn of the same length. Thorax with three stout ribs in its wall,
and with subregular, hexagonal pores increasing in size towards the girdle. Abdomen flatter than
the thorax, without ribs, nearly horizontal, with subregular, square pores, disposed in four to six
concentric, subcircular series of different sizes ; decreasing in size towards the wide open mouth.
Seen from the side, this species resembles Corocalyptra agnesce, (PI. 59, fig. 3).

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'04 ; breadth, a 0'03, b 012, c 0'2.

Habitat. — Central Pacific, Stations 260 to 274, surface.

2. Theopilium triradiatum, n. sp.

Shell flatly conical, smooth, in general of the same form as, and with similar feuestration to, the
preceding species, but different in the proportions. Length of the three joints = 1:4:2, breadth =
2:4:6. Cephalis hemispherical, with two divergent, thin horns of the same length. Thorax more
elevated, about as high as broad. The three divergent ribs are not limited to the thorax, but pro-
longed through the whole abdomen, the outline of which is a prolongation of that of the thorax.

Dimensions. — Length of the three joints, a 0'025, b 01, c 0'05 ; breadth, a 0'05, 6'0'l,.c 015.

Habitat. — Tropical Atlantic, Station 347, surface.

3. Theopilium cranoides, Haeckel.

Eucyrtidium cranoides, Haeckel, 1862, Monogr. d. Kadiol., p. 320, Taf. vii. figs. 1-3.

Shell campanulate-conical, smooth. Length of the three joints = 2 : 5 : 4, breadth = 3 : 9 : 10.
Cephalis ovate, with a straight, excentric, prismatic horn of the same length. ^ The campanulate
thorax is separated from it by no external collar stricture, but by an internal septum. From the
base of the horn arise three divergent radial ribs, running in the wall of the two first joints to the
lumbar stricture (loc. tit., Taf. vii. fig. 3). Abdomen short and wide, without ribs. Pores rather
large, regular, circular, quincuncial, in the cephalis smaller. Central capsule four-lobed.

Dimensions. — Length of the three joints, a 0'027, b 0'054, c 0'047 ; breadth, a 0'03, b 0'0'J,
c 01.

Habitat. — Mediterranean (Messina), surface.

Genus 584. Corocalyptra,1 n. gen.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three simple,
free, lateral wings, arising from the collar stricture between cephalis and thorax.

The genus Corocalyptra comprises a small number of very elegant hat-shaped
Tricyrtida, which resemble greatly Eiicecryphalus among the Dicyrtida. As in the

1 Corocalyptra = Coif or Lood of a girl ; xoji),

REPORT ON THE RADIOLARIA. 1323

latter, three free, radial spines, or simple wings, corresponding to the three basal feet of
Cortina, arise from the collar stricture between the small hemispherical cephalis and the
large, flatly conical thorax. Corocalyptra differs from Eucecryphalus, its ancestral
form, in the development of a flat and broad abdomen, which is a prolongation of the
thorax, and may be compared to the brim of a hat.

1. Corocalyptra agnesce, n. sp. (PI. 59, fig. 3).

Shell flatly conical or hat-shaped. Length of the three joints = 1:4:2, breadth = 2:8:12.
Cephalis hemispherical, with an oblique, small, conical horn of the same length. From the slight
collar stricture arise three slender, conical feet of equal length, twice as long as the apical horn,
nearly horizontally divergent. Lateral outline of the conical thorax straight, of the flatter abdomen
convex ; the smooth margin of the abdomen turned inwards. Network delicate, with subregular,
hexagonal pores.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'04 ; breadth, a 0'03, b 015, c O24.

Halitat. — Central Pacific, Station 270, surface.

2. Corocalyptra elisabethce, n. sp. (PI. 59, fig. 10).

Shell flatly conical, hat-shaped, very similar to the preceding species, but with different propor-
tions. Length of the three joints = 1:4:2; breadth = 1:7:10. Cephalis very small, with an
oblique horn of the same length. The three feet are of different sizes, the caudal odd foot being twice
as long as the two lateral, which are equal to the horn. Lateral outline of the campanulate
thorax convex, of the flatter abdomen less convex. Margin of the mouth flat.

Dimensions. — Length of the three joints, a 0'015, b 0'06, c 0'03 ; breadth a 0'02, b 014, c 0'2.

Habitat. — Tropical Atlantic, Station 347, surface.

3. Corocalyptra emmce, n. sp. (PI. 59, fig. 4).

Shell nearly conical, hat-shaped. Length of the three joints = 1:3:1, breadth = 1:5:7.
Cephalis hemispherical, with a straight horn of the same length. Feet of the collar larger than in
the preceding species, the two lateral smaller being directed upwards, the larger odd caudal down-
wards. Thorax slightly campanulate ; its hexagonal meshes two to four times as large as those of
the short, convex abdomen, which is turned inwards.

Dimensions.— Length of the three joints, a 0'02, b 0'09, c 0'03 ; breadth, a 01)25, b 013, c 017.

Habitat. — Central Pacific, Station 272, surface.

4. Corocalyptra maryarethce, n. sp.

Shell nearly conical, hat-shaped, very similar to the preceding species, but with much more
delicate hexagonal network, with thread-like bars. Length of the three joints = 1:7:2, breadth =

1324 THE VOYAGE OF H.M.S. CHALLENGER.

1:10:12. Cephalis hemispherical, with six bristle-shaped spines of half the length of the shell ;
three horns divergent upwards, and three alternating feet divergent downwards. Thorax nearly
conical. Abdomen flatter.

Dimensions. — Length of the three joints, a 0'015, b O'l, c O03 ; breadth, a 0-02, b 0'15, c 0'18.

Habitat. — North Pacific, Station 236, surface.

5. Corocalyptra ludovicce, n. sp.

Shell flatly campanulate or hat-shaped. Length of the three joints = 1:4:3, breadth = 2:7:10.
Cephalis hemispherical, with six bristle-shaped spines, about one-fourth to one-third as long as the
shell ; three horns diverging upwards, and three alternate feet diverging downwards. Thorax
nearly conical Abdomen much larger than in all preceding species, inflated, with convex, lateral
outline; its mouth-edge curved inwards. The network is much finer than in the similar Corocalyptra
cmmce (PL 59, fig. 4), and the abdomen is relatively twice as long and broad.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'06 ; breadth, « 0'04, b 014, c 0'2.

Habitat. — Central Pacific, Station 271, surface.

Genus 585. Dictyoceras,1 Haeckel, 1862, Monogr. d. Radiol., p. 333

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three latticed
free lateral wings on the sides of the thorax, which are not prolonged into the
cephalis.

The genus Dictyoceras and the following Pteropilium agree with the two preceding
genera in the possession of three lateral wings on the sides of the thorax ; but whilst
these in the latter are simple solid spines, they are in the former vertical fenestrated
plates. Dictyoceras may be derived from Pterocorys by development of a vertical
lattice-plate between the thorax and the three free lateral spines arising from it.

1. Dictyoceras insectum, n. sp. (PL 71, figs. G, 7).

Shell with two distinct strictures. Length of the three joints =1 : 3 : 2, breadth = 2 : 4 : 3.
Cephalis hemispherical, with a slender pyramidal horn of twice the length. Thorax subspherical,
in the upper half with three divergent lattice-wings of the same length, each of which represents a
slender, fenestrated, three-sided pyramid. Abdomen subovate, with wide, truncate mouth (in the
figured specimen broken off). Pores circular, small, of different sizes.

Dimensions. — Length of the three joints, a 0'025, b 0'055, c 0'04 ; breadth, a 0'035, I 0'08,
c 0-06.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

1 ZH'ttyoc<Tas = Reticulated horn ; ^IxTvov, r.t^ot:.

REPORT ON THE RADIOLARIA. 1325

2. Dictyoceras formica, n. sp. (PI. 71, fig. 8).

Shell with obliterate collar, but deep lumbar stricture. Length of the three joints = 1:2:3,
breadth = 2:5:4. Cephalis conical, with an oblique curved horn of the same length. Thorax
with three vaulted swellings between the three prominent, diverging lattice-wings, the apex of
which is prolonged downwards into a solid curved spine, half as long as the inflated abdomen.
Mouth little constricted. Pores irregular, roundish, of different sizes.

Dimension. — Length of the three joints, a 0'02, I 0'04, c 0'06 ; breadth, a 0'03, I 01, c 0"09.

Habitat. — North Atlantic, Station 353, surface.

3. Dictyoceras melitta, n. sp. (PI. 71, fig. 9).

Shell with two deep strictures. Length of the three joints = 1:3:4, breadth = 1:6:5.
Cephalis subspherical, with two conical divergent horns of the same length. Thorax three-sided
pyramidal, the three edges prolonged into three lattice-wings of the same form, with short, terminal
spines. Abdomen inflated, subovate, with constricted mouth. Pores small, regular, circular, of
equal size, with very thin bars.

Dimensions. — Length of the three joints, a 0'03, b 0'09, c 012 ; breadth, a 0'04, b 018, c 015.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

4. Dictyoceras bombus, n. sp. (PI. 71, fig. 10).

Shell with deep collar, but evanescent lumbar stricture. Length of the three joints =1 : 5 : 3,
breadth = 1:6:7. Cephalis subspherical, with a conical horn of the same length. Thorax cam-
panulate, with three short and broad, triangular lattice-wings, the upper edge of which is nearly
horizontal, the lower nearly vertical and decurrent from the height of the collar to the lumbar
stricture. Abdomen inflated, with constricted mouth of half the breadth. Pores small, subregular,
circular, of nearly equal size.

Dimensions. — Length of the three joints, a Oi)2, b 01, c 0'06 ; breadth, « 0'025, b 012, c 014.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Dictyoceras virchouni, Hacckel.

Didyoctras vircliowii, Haeckel, 1862, Monogr. d. Radiol., p. 333, Taf. viii. figs. 1-5.
Lithornithium dictyoceras, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, I860,

p. 840.

Shell with two distinct strictures. Length of the three joints = 1:3:4, breadth = 1:5:6,
Cephalis subspherical, with an oblique curved horn of the same length. Thorax conical, with three
broad, triangular lattice-wings different in size and direction, two of which are directed outwards,
the third downwards — each terminated by a strong spine. Abdomen oblique, inflated, with wide
open, truncate mouth. On the shell surface some few conical spines are scattered. Pores irregular,

1326 THE VOYAGE OF H.M.S. CHALLENGED.

roundish, of different sizes. On the peculiar symmetry of this remarkable form, compare the
detailed description in my Monograph.

Dimensions. — Length of the three joints, a 0'02, J 0'06, c 0'08 ; breadth, a 0'02, b 01, c 012.

Habitat. — Mediterranean, Messina, surface.

Gemi3 586. Pteropilium,1 Haeckel, 1881, Prodromus, p. 435.

Definition. — Theopilida (vel Tricyrtida triradiata aperta) with three latticed
free lateral wings on the sides of the thorax, prolonged into the horn of the cephalis in
the form of three vertical, free cephalic wings.

The genus Pteropilium differs from the preceding closely allied Dictyoceras in the
development of three free, vertical, latticed cephalic wings, expanded between the apical
horn of the cephalis and the three wings of the thorax ; they may be direct prolongations
of the latter. Pteropilium, however, may also be derived directly from the Dicyrtida
Callimitra or Clathrocorys by development of an abdomen. All these interesting
forms are closely allied to the Plectoidea.

Subgenus 1. Clathropilium, Haeckel, 1881, Prodromus, p. 435.

Definition. — Thorax completely latticed, without three larger lateral holes between
the three wings.

1. Pteropilium stratiotes, n. sp. (PI. 70, figs. 9, 10).

Shell thin-walled, with two deep strictures. Length of the three joints = 1:5:4,
breadth = 2 : 6 : 9. Cephalis hemispherical, with a vertical, straight, prismatic horn of three
times the length. Thorax inflated, oblique, with three slender, nearly straight, widely divergent
ribs, beginning from the collar stricture and united in its centre with the centripetal prolongation
of the horn. The basal half of the three ribs is enclosed in the thorax wall, whilst the distal half
lies outside it, and is connected with its lower half only by two divergent, reticulated wings. The
upper edge of the ribs is connected with the occipital horn by a vertical, loosely reticulated,
triangular wing. Abdomen half as long as the thorax, also of irregular and oblique form, with
knee-shaped outline and a wide, truncate mouth. Network with irregular polygonal, for the most
part quadrangular, meshes, separated by thin bars and forming irregular transverse rows. Some
stronger, vein-like ribs ramify in the wall, diverging towards the mouth.

Dimensions. — Length of the three joints, a 0'03, b 01, c 0'08 ; breadth, a 0'04, b 012, c 018.

Habitat. — Central Pacific, Station 271, surface.

1 Pteropilium = Small hat with wings ;

REPORT ON THE RADIOLARIA. 1327

2. Pteropilium, hoplites, n. sp.

Shell in the general form and in the irregular, quadrangular fenestration similar to the
preceding species, but more heavy and with different proportions. Length of the three joints =
1:6:4, breadth = 2:6:8. Cephalis twice as broad as in Pteropilium stratiotes. Thorax more
slender and subovate. Abdomen truncate, conical, gradually dilated, with straight, non-geniculate
outline. Network coarser, with larger square meshes and thicker bars.

Dimensions. — Length of the three joints, a O03, b 012, c 0'08 ; breadth, a 0'05, b 012, c 016.

Habitat.— Central Pacific, Station 272, depth 2600 fathoms.

3. Pteropilium eques, n. sp.

Shell in the general form and in the irregular, quadrangular fenestration similar to those of the two
preceding species, but more slender and with different proportions. Length of the three joints =
1:3:2, breadth = 2:4:4. Cephalis flatter. Thorax subconical, also flatter. Abdomen short,
cylindrical, with straight outline. Network looser than in the two preceding species, with larger
square meshes and thinner bars.

Dimensions. — Length of the three joints, a 0'03, b 0'08, c 0'06 ; breadth a 0'06, 6 012, c 012.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Subgenus 2. Arachnopilium, Haeckel, 1881, Prodromus, p. 435.
Definition. — Thorax with three large lateral holes between the three latticed wings.

4. Pteropilium, dathrocanium, n. sp. (PI. 64, fig. 7).

Arachnopilium dathrocanium, Haeckel, Prodromns, 1881, p. 435.

Shell very delicate, with two deep strictures. Length of the three joints = 2:4:2,
breadth = 2:10:5. Cephalis subspherical, with circular, polygonally-framed pores, and a central,
three-sided pyramidal, apical horn of twice the length. Thorax three-sided pyramidal, with
three large, ovate holes between three prominent latticed wings. From its surface arises a very
delicate, arachnoidal network with irregular, polygonal meshes, enveloping also the entire cephalis.
Abdomen wide and short, as long as the cephalis, and half as broad as the distance of the wings,
twice as broad as the constricted mouth.

Dimensions. — Length of the three joints, a 0'04, b 0'08, c 0'04 ; breadth, a 0'05, b 0'2, c 01.

Habitat.— Central Pacific, Station 271, depth 2425 fathoms.

1328 THE VOYAGE OF H.M.S. CHALLENGER.

Genus. 587. Theopodium,1 Haeckel, 1881, Prodromus, p. 435.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three divergent
solid ribs, which lie in the wall of the thorax and the abdomen, and are prolonged
into three solid terminal feet.

The genus Theopodium and the following closely allied Pterocanium differ from
the preceding four genera in the development of the three radial rods or the primary
cortinar spines, which are not free lateral wings, but longitudinal ribs enclosed in the
wall of the thorax and abdomen, and prolonged over the basal mouth into three
free terminal feet. These are solid in TJieopodiiim, which, therefore, corresponds to
Lychnocanium among the Dicyrtida.

1. TJieopodium tricostatum, n. sp. (PI. 97, fig. 14).

Shell three-sided pyramidal, thorny, with two distinct strictures. Length of the three
joints = 1:2:2, breadth = 1:3:4. Cephalis hemispherical, with a stout conical horn of the same
length. Thorax with regular, circular, hexagonally-framed pores. Abdomen with irregular,
roundish pores of very different sizes. From the middle part of the thorax arise the three
prominent, wing-like edges of the pyramid, which are prolonged over its wide mouth into three
stout, pyramidal, divergent feet about as long as the thorax, with dentate, lamellar edges.

Dimensions. — Length of the three joints, a 0'02, 6 0'07, c 0'06 ; breadth, a 0'04, & O09, c 012.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Theopodium, pyramidale, n. sp.

Shell three-sided pyramidal, rough, without external strictures, but with two broad internal
girdles. Length of the three joints = 1:2:6, breadth = 2:4:8. Cephalis with a thick horn of
the same length, conical. Thorax with very small, regular, circular pores. Abdomen with
irregular, roundish pores of very different sizes. From the collar stricture arise the three recti-
linear edges of the pyramid, which are prolonged over its wide-open mouth into three stout,
divergent, pyramidal feet, about as long as the thorax.

Dimensions. — Length of the three joints, a 0'02, & 0'04, c 012 ; breadth, a 0'04, & 0'075, c 015.

Habitat. — Fossil in Barbados.

Genus 588. Pterocanium^ Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three divergent
ribs, which run along the thorax and abdomen, and are prolonged into three latticed
terminal feet.

1 Theopodium = Divine foot ; iio;, is-itiiov.

2 Pterocanium = Basket with wings ; TTSJO'I/, nation.

REPORT ON THE RADIOLARIA. 1329

The genus Pterocanium differs from the preceding Theopodium in the fencstration of
the three terminal feet, which are basal prolongations of the three radial ribs, enclosed in
the wall of the thorax and the abdomen. Often also these ribs are partly or wholly
fenestrated. It corresponds to Lychnodictyum among the Dicyrtida, and may be
derived from this by development of an abdomen. The latter forms sometimes three
concave bays, at other times three convex lobes between the three latticed feet.

Subgenus 1. Pterocanarium, Haeckel.

Definition. — Free basal edge of the abdomen between the three feet concave, forming
three shallower or deeper bays between them.

1. Pterocanium proserpinoe, Ehrenberg.

Pterocanium proserpince, Ehrenberg, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, 1872,

p. 299, Taf. xi. fig. 22.
Pterocanium proserpince, Haeckel, 1862, Monogr. d. Radiol., p. 332.

Shell campanulate, rough. Length of the three joints = 1:4:2, breadth 1:5:6. Cephalis
subspherical, with a triangular-pyramidal vertical horn of thrice the length. Thorax hemispherical,
without prominent swellings. Abdomen shorter, with three concave basal bays. Pores in the
thorax and abdomen nearly equal, subregular, circular. Feet from the girdle (or the lumbar
stricture) little divergent, nearly straight.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'04 ; breadth, « O3, b 01, c 012.

Habitat. — Mediterranean, Candia, Spratt, depth 1100 fathoms.

2. Pterocanium gravidum, n. sp., (PI. 73, fig. 3).

Shell campanulate, nearly three-sided pyramidal, smooth. Length of the three joints = 1:4:3,
breadth = 1:6:10. Cephalis subspherical, with a pyramidal straight horn of twice the length,
Thorax hemispherical, without prominent swellings. Abdomen shorter, with three concave basal
bays ; its network prolonged to the ends of the feet. Pores in the thorax and abdomen of nearly
equal size, irregular, roundish. Feet from the girdle strongly divergent, with convex back.

Dimensions. — Length of the three joints, a 0'015, b 0'075, c 0'06 ; breadth, a 0'02, b 012, c 0'2.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

3. Pterocanium orcinum, n. sp. (PI. 73, ng. 2).

Shell campanulate, nearly three-sided pyramidal, covered with conical spines. Length of the
three joints = 1:4:3, breadth = 1:5:6. Cephalis hemispherical, with a conical horn of the
same length. Thorax without prominent swellings, with subregular, circular pores. Abdomen

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 167

1330 THE VOYAGE OF H.M.S. CHALLENGER.

shorter, with three concave basal edges and irregular, polygonal pores. Feet from the girdle
strongly divergent, nearly straight.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 006 ; breadth, a 0'03, b 01, c 012.

Habitat. — Central Pacific, Station 263 to 274, depth 2350 to 2925 fathoms.

4. Pterocanium contiguum, Ehrenberg.

Pterocanium contiguum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, Taf. xvii. fig. 7.

Shell three-sided pyramidal, smooth. Length of the three joints =1 : 3 : 2, breadth = 1 : 4: 6.
Cephalis small, subspherical, with a large conical horn three times the length. Thorax and
abdomen with small, regular, circular pores of equal size, densely crowded together, with
thin bars. Abdomen shorter, with three concave basal edges. Feet very thick, straight, from
the girdle strongly divergent.

Dimensions. — Length of the three joints, a O'OIS, b 0'05, c 0'025 ; breadth a 0'02, b 0'08, c 012.

Habitat. — Fossil in Barbados.

5. Pterocanium pyramis, n. sp. (PL 68, fig. 7).

Shell three-sided pyramidal, smooth. Length of .the three joints =1:4:3, breadth = 2 : 4:6,
Cephalis hemispherical, with a conical horn of the same length. Thorax campanulate, with fifteen
to twenty prominent longitudinal ribs, separating as many rows of regular, circular pores. Abdomen
shorter, with three concave basal bays, and irregular, roundish pores. Feet very strong, pyramidal,
straight, gradually divergent from the girdle.

Dimensions. — Length of the three joints, a 0'025, b 0'08, c 0'06 ; breadth, a 0'04, b 0'08, c 012.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

6. Pterocanium virgineum, n. sp. (PI. 73, fig. 6).

Shell nearly three-sided pyramidal, smooth. Length of the three joints = 1:4:8, breadth
2:6:9. Cephalis hemispherical, with a conical straight horn three times the length. Thorax
campanulate, with three slight swellings between the three knee-shaped ribs, and with regular
circular pores. Abdomen longer, with three concave basal bays, and with very small and
numerous pores (much smaller than those of the thorax). At both sides of the three prominent
abdominal crests, two rows of larger, nearly square pores occur. Feet slender, nearly straight,
divergent.

Dimensions. — Length of the three joints, a 015, b O06, c 012 ; breadth, a 0'03, b 0'09, c 014.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

7. Pterocanium prcetextum, Haeckel.

Lychnocanium prcetextum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. lierlin, p. 297, Taf. x.

fig. 2.

Shell nearly three-sided prismatic, smooth. Length of the three joints = 1 : 2 : 1, breadth =
1:4:4. Cephalis subspherical, with a straight, conical horn of three times the length. Thorax

REPORT ON THE RADIOLARIA. 1331

campanulate with three slight swellings between the three knee-shaped ribs, and with regular, circular
pores. Abdomen smaller, with three deep concave basal bays, and with irregular, roundish pores.
Feet longer than the shell, slender, pyramidal, straight, parallel.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'02 ; breadth, a 0'02, I O'OT, c 0'07.

Habitat. — Indian Ocean, Ceylon (Haeckel) ; Zanzibar (Pullen).

8. Pterocanium depressum, Haeckel.

Lychnocanium depressum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf. x.

fig. 1.

Shell (including the feet) nearly three-sided prismatic, rough. Length of the three joints =
1:2:1, breadth = 1:6:6. Cephalis subspherical, with a conical horn of the same length. Thorax
a very flat and broad triangular pyramid, three times as broad as long. Abdomen smaller, with
three deep, parabolic, concave bays. Pores irregular, roundish. Feet longer than the shell, slender,
pyramidal, straight, parallel.

Dimensions. — Length of the three joints, a 0'02, I 0'04, c 0'02 ; breadth, a 0'025, b 012, c 012.

Habitat. — Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).

9. Pterocanium campanella, Haeckel.

Lychnocanium campanella, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 297, Taf.

viii. fig. 12.
Podocyrtis campanella, Ehrenberg, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 769.

Shell campanulate, smooth, with three high fenestrated crests and deep collar stricture. Length
of the three joints — I : 3 : 1, breadth = 1 : 4 : 3. Cephalis subspherical, with a slender horn 'of the
same length. Thorax inflated, campauulate, with three vaulted swellings between the three curved
ribs. Abdomen short, with three semicircular bays between the three feet. Pores of the whole
shell regular, circular, small, and numerous. Feet broad, triangular, shorter than the thorax, with
convex back and convergent ends.

Dimensions. — Length of the three joints, a 0'015, b 0'06, c 0'2 ; breadth, a 0'02, b 0'08, c 0'07.

Habitat. — Western Tropical Pacific, Philippine Sea, 3300 fathoms (Brooke).

10. Pterocanium tricolpum, n. sp. (PI. 73, fig. 1).

Shell nearly three-sided prismatic, smooth, with three high fenestrated crests and two deep
strictures. Length of the three joints = 1:3:2, breadth =1:5:5. Cephalis subspherical, with an
oblique, conical horn of the same length. Thorax inflated, with three highly vaulted bosoms between
the three high crests, and with subregular, circular pores. Abdomen shorter, with three concave
(or nearly rectangular, square) basal bays between the three feet, and with irregular, roundish pores,
three to four pairs of larger pores occurring at the sides of the base of the feet. Feet nearly as long as
the shell, with fenestrated bases, nearly straight and parallel ; somewhat convergent, with convex back.
(Often the concave bays between the three feet are not square, as in the specimen figured, but semi-

1332 THE VOYAGE OF H.M.S. CHALLENGER.

circular.) The ends of the feet are sometimes strongly convergent. The vaultings of the three
swellings and the reticulation are also variable ; the whole form is often irregular.

Dimensions. — Length of the three joints, a 0'02, I 0'06, c O04 ; breadth, a 0-025, b 01, c 01.

Habitat. — Cosmopolitan ; Atlantic, Pacific ; many stations, surface.

Subgenus 2. Pterocanidium, Haeckel.

Definition. — Free basal edge of the abdomen between the three feet convex, forming
three rounded or semicircular prominent lobes between them.

11. Pterocanium eucolpum, n. sp. (PI. 73, fig. 4).

Dictyopodium eucolpum, Haeckel, 1881, Prodromus et Atlas.

i

Shell about triangular-prismatic, with two deep strictures, smooth. Length of the three joints
= 1:3:3, breadth = 1:3:4. Cephalis subspherical, with a conical, oblique horn of the same
length. Thorax inflated, with three hemispherical swellings between the three high crests, and with
subregular, hexagonal pores. Abdomen longer, with much smaller, irregular, roundish pores, forming
three broad, convex lobes between the three feet. (In the figured specimen the lobes were not fully
developed, and extremely thin below the line parallel to the edge. In another specimen, found
afterwards in the same locality, the three lobes were much larger, semicircular, and reached almost
to the basal plane of the ends of the feet by reason of their convexity.) Feet strong, with slightly
convex back, divergent.

Dimensions. — Length of the three joints, a 0'03, b 0'09, c 01 ; breadth, a 0'03, I 0'09, c 012.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

12. Pterocanium bicorne, n. sp. (PI. 73, fig. 5).

Didyopodium bicorne, Haeckel, 1881, Prodromus et Atlas.

Shell nearly three-sided pyramidal, slender, smooth. Length of the three joints = 1:2:2,
breadth = 1:4:4. Cephalis hemispherical, with two oblique, conical horns of nearly equal length.
Thorax nearly hemispherical, with slightly prominent crests, and with subregular, hexagonal pores.
Abdomen of about the same length, with much smaller, irregular, roundish pores, forming three
convex, nearly circular lobes between the three large divergent feet. These are slender, three-sided
pyramidal, longer than the shell, fenestrated at the thickened base, with some rows of larger pores ;
their back is slightly concave.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'04 ; breadth, a 0'02, b 0'08, c 0'09.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

REPORT ON THE RADIOLARIA.

1333

13. Pterocanium trilobum, Haeckel.

Dictyopodium trilobum, Haeckol, 1882, Monogr. d. Radiol., p. 340, Taf. viii. figs. 6-10.

Shell three-sided pyramidal, nearly tetrahedral, covered with conical spines. Length of the
three joints = 1 : 4 : 2, breadth = 1 : 6 : 10. Cephalis hemispherical, with a large conical horn (as
long as the thorax). Thorax tetrahedral, with little prominent crests. Abdomen forming three
semicircular, convex lobes between the. three feet, half as long as the thorax, with the same irregular,
roundish pores. Feet slender, about as long as the shell, triangular, with convex back, strongly
divergent, fenestrated at the inflated and thickened base. (Compare the special description of the
living form and its soft body in my Monograph.)

Dimensions. — Length of the three joints, a 0'02, b O'OS, c 0'04; breadth, a 0'03, b 012, c 0'2.

Habitat. — Mediterranean, Messina, surface.

Genus 589. Pterocodon,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — T li e o p i 1 i d a (vel Tricyrtida triradiata aperta) with three solid
free lateral wings on the thorax, and numerous solid terminal feet around the mouth
of the abdomen.

The genus Pterocodon differs from the closely allied Pterocorys, its ancestral form,
in the development of numerous solid feet around the terminal mouth, similar to the
terminal corona of Calocydas.

1. Pterocodon campana, Ehrenberg.

Pterocodon campana, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 10.

Pterocodon campana, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xix. fig. 1.

Shell slender, campanulate, subconical, with two distinct strictures. Length of the three joints
= 1 :2 :4, breadth = 2 : 3 : 5. Cephalis hemispherical, with a conical horn of twice the length.
Thorax hemispherical, in the upper part with three divergent, conical horns, as long as the cephalis,
and curved downwards. Abdomen with four transverse rows of large circular pores, increasing in
size towards the mouth ; the largest (undermost), five times as broad as the circular thoracic pores.
Mouth not constricted, with a corona of twelve to fifteen divergent, conical feet.

Dimensions. — Length of the three joints, a 0'015, I 0'03, c 0'06 ; breadth, a 0'02, I 0'05, c 0'08.

Habitat. — Fossil in Barbados.

2. Pterocodon ornatus, n. sp. (PI. 70, fig. 11).

Shell nearly ovate, with two deep strictures. Length of the three joints = 1:3:5, breadth
= 1:5:7. Cephalis hemispherical, with a Large oblique horn reaching half the length of the

1 Pterocodon = Bell with wings ; tm'^n, x.ului.

1334 THE VOYAGE OF H.M.S. CHALLENGER.

shell ; three edges of the horn wing-shaped and dentated. Thorax hemispherical, in the middle
zone with three conical wings, which are half as long as the thorax, and curved downwards.
Pores hexagonal, roundish, twice as hroad in the inflated abdomen' as in the thorax. Mouth
constricted, with a corona of from fifteen to eighteen conical, divergent, curved feet, similar to the
thoracic wings.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c O'l ; "breadth, a 0'025, b O'l, c 0'14.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Pterocodon favosus, n. sp.

Shell ovate, with two slight 'strictures. Length of the three joints = 1:2:2, breadth = 2:4:4.
Cephalis hemispherical, with a conical horn of twice the length. Three wings of the thorax equal
to those of the preceding species. Pores regular, circular, hexagonally framed, of equal size in
the thorax and abdomen. Mouth constricted, with a corona of nine straight, conical, nearly
vertical feet.

Dimensions. — Length of the three joints, a 0'0025, b 0'05, c 0'05 ; breadth, a 0'05, b 0'09, c 01.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 590. Dictyocodon,1 Haeckel, 1881, Prodromus, p. 435.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three latticed
free lateral wings on the thorax, and numerous latticed terminal feet around the mouth
of the abdomen.

The genus Dictyocodon, one of the most elegant among the NASSELLARIA, differs
from the preceding Pterocodon in the fenestration of the three lateral wings of the
thorax, and the numerous terminal feet of the abdomen. It may be derived from
Dictyoceras by development of regular lattice-feet around the terminal mouth.

Subgenus 1. Dictyocodella, Haeckel.
Definition. — The three lateral lattice-wings arise from the thorax alone.

1. Dictyocodon annasethe, n. sp. (PL 71, fig. 11).

Shell with two deep strictures. Length of the three joints = 2:5:4, breadth =1:5:6.
Cephalis subspherical, with a very large, three-sided prismatic horn of three times the length,
bearing at the base some smaller accessory spines. Thorax nearly conical, with three large, inflated,
triangular lattice-wings, the upper edge of which (the cortinar rod) descends obliquely, and is larger

1 Dictyocodon = Net-bell ; lixrvov, tabu*.

REPORT ON THE RADIOLARIA. 1335

than the thorax, ending in a spine. Abdomen inflated, subcylindrical, divided at the wide open mouth
by nine deep incisions into nine large triangular feet. Network in the thorax and wings composed
of small, regular, hexagonal pores, in the abdomen of three transverse rows of irregular, very large
pores, which are surrounded and separated by bands of very small pores ; in each foot one large
pore and a marginal series of very small" pores occur. I dedicate this wonderful species to the
memory of my dear wife, Anna Sethe.

Dimensions. — Length of the three joints, a O04, b 01, c 0'08 ; breadth, a 0'03, I 01, c 012.

Habitat. — Indian Ocean ; Cocos Islands (Rabbe), surface.

2. Dictyocodon carolotce, n. sp. (PI. 71, fig. 14).

Shell with two deep strictures. Length of the three joints = 1 : 3 : 1, breadth = 2 : 5 ! 6.
Cephalis hemispherical, with an oblique pyramidal horn of twice the length. Thorax subconical,
in the upper half with three divergent, triangular wings of half the length, the upper edge of which
is nearly horizontal, little curved. Abdomen nearly cylindrical ; divided at the wide open mouth
by nine deep incisions into nine triangular, vertical feet, about as large as the wings. Network very
delicate, with regular, small, circular pores of equal size and very thin bars. I dedicate this elegant
species to my dear mother, Charlotte Sethe.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 014 ; breadth, a 0'04, b 01, c 012.

Habitat. — Cape of Good Hope (Bleek), surface.

Subgenus 2. Dictyocodoma, Haeckel.
Definition. — The three lateral wings are prolonged from the thorax to the abdomen.

3. Dictyocodon palladius, n. sp. (PI. 71, figs. 12, 13).

Shell with distinct collar, but evanescent lumbar stricture. Length of the three joints =1:2:7,
breadth = 1:3:8. Cephalis very small, with a large pyramidal horn of twice the length, bearing
at its base some small, often branched, accessory spines. Thorax three-sided pyramidal, without
external boundary prolonged into the large, inflated, gradually dilated abdomen. The internal boundary
between the two is marked by a fenestrated, horizontal ring (not indicated in the figure). Three
prominent, triangular, fenestrated wings arise from the base of the cephalic horn, and are prolonged
nearly through the whole shell almost to the edge of the mouth ; in its lower half they form three
elevated fenestrated apophyses, the upper edge of which is nearly horizontal Mouth divided by
about twenty incisions into as many triangular, vertical, fenestrated feet. The network of the
whole shell is very delicate, like fine gauze, composed of very small, regular, hexagonal pores.

Dimensions. — Length of the three joints, a 0'03, b 0'055, c 0'21 ; breadth, a OD3, b 0'09, c 0'25.

Habitat. — Central Pacific, Station 271, surface.

1336 THE VOYAGE OF H.M.S. CHALLENGER.

4. Dictyocodon prometheus, n. sp.

Shell tower-shaped, very similar to the preceding species in form and fenestration, but more
slender and different in the longer and three-sided prismatic abdomen. Length of the three joints
= 1:1:8, breadth = 1:3:7. Cephalis with two large divergent horns of three times the length,
which are united by interior prolongations with the basal central point, from which arise the upper
edges of the three divergent wings ; the ends of the latter are directed downwards. Mouth with a
corona of about thirty irregular, triangular feet.

Dimensions. — Length of the three joints, a O03, b 0'03, c 0'25 ; breadth, « 0'03, b 0'08, c O2.

Habitat. — Tropical Atlantic, Station 347, surface.

Genus 591. Pleuropodium,1 Haeckel, 1881, Prodromus, p. 436.

Definition. — Theopilida (vel Tricyrtida triradiata aperta) without ribs in the
thorax, but with three ribs enclosed in the abdomen, which are prolonged into three
terminal feet.

The genus Pleuropodium, formerly confounded with Theopodium and Pterocanium,
differs from these two closely allied ancestral genera in the localisation of the three lateral
ribs, which have disappeared in the thorax and become limited to the abdomen. It is
therefore intermediate between the former and the following Podocyrtis.

1. Pleuropodium charybdeum, Haeckel.

Pterocanium chanjbdf.um, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 43, Taf. vi.

figs. 7-10.
Podocyrtis charybdea, J. Miiller, 1856, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 492.

Shell campanulate, armed with scattered, bristle-shaped spines, with sharp collar and slight
lumbar stricture. Length of the three joints =1:3:1, breadth = 1:4:5. Cephalis cupola-
shaped, with a large prismatic, somewhat curved horn, half as long as the shell. Thorax hemi-
spherical, spiny. Abdomen short and wide, three-sided prismatic, with three stout longitudinal ribs,
which are prolonged into three slender, prismatic, nearly vertical, slightly curved feet, about as
long as the shell. Pores irregular, roundish, of variable size.

Dimensions. — Length of the three joints, a 0'02, b O'OG, c 0'03 ; breadth, a 0'03, b OOS, c O'l.

Habitat. — Mediterranean (Messina, Nice, &c.), surface.

2. Pleuropodium cortina, n. sp.

Shell campanulate, smooth, with two distinct strictures. Length of the three joints = 1:4:2,
breadth = 1:3:4. Cephalis subspherical, with a small, pyramidal, straight horn of the same length.

1 Pleuropodium = Shell with ribs and feet ; wXeJ/;a, voliw.

REPORT ON THE RADIOLARIA. 1337

Thorax pear-shaped, with regular, circular, hexagonally-framed pores. Abdomen three-sided
pyramidal, with irregular, roundish pores and three prominent, stout, prismatic ribs, which are
prolonged into three straight, divergent feet of the same length.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'04 ; breadth, a 0'025, b 0'06,c 0'08.

Habitat. — North Atlantic, Station 354, surface.

Genus 592. Podocyrtis? Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 54.

Definition. — Theopilida (vel Tricyrtida triradiata aperta) with three simple,
terminal feet on the mouth of the abdomen, without lateral ribs or wings. Apex with a
horn, which usually is simple.

The genus Podocyrtis, and the two following closely allied genera, differ from all the
preceding Theopilida in the absence of lateral ribs or wings, and the possession of three
free terminal feet, which arise directly from the peristome, or from the margin of the
abdominal mouth. They may be derived from Pleuropodium by reduction and loss of the
three piercing lateral ribs, the terminal free prolongations of which only remain. The genus
Podocyrtis is one of the largest and most common among all C y r t o i d e a, being rich
mainly in fossil forms. Ehrenberg in his Polycystins of Barbados (1875, loc. cit.,
p. 80) enumerated not less than thirty-one species. Some of these are yet living, and
occur in the Pacific Radiolarian ooze collected by the Challenger. Other new forms
are to be added, so that the number of species described in the following pages amounts
to forty-five. Many of these are cosmopolitan, or at least common and widely distributed.
To facilitate study we may divide this large genus into four subgenera : in two of these
the terminal feet are divergent, or nearly parallel ; in the two others convergent. In
each of these two groups the pores of the thorax and the abdomen are either nearly
equal in size and form, or distinctly different, the abdominal pores being often much
larger than the thoracic. The small cephalis bears constantly an apical horn, which is
usually simple, rarely branched.

Subgenus 1. Podocyrtarium, Haeckel.

Definition. — Feet divergent (the distance between their ends being greater than
that between their bases). Pores of the thorax and abdomen nearly equal in size and
similar in form.

1 Podocyrtis = Basket with feet ; vavf, *vp!f.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 168

1338 THE VOYAGE OF H.M.S. CHALLENGES.

1. Podocyrtis tnpodiscus, n. sp. (PL 72, fig. 4).

Shell nearly conical, gradually dilated from the apical to the basal part, with two slight
strictures. Surface a little rough. Length of the three joints = 1 : 2:4, breadth = 2:4:6. Pores
subregular, circular, quincuncially disposed, of nearly equal size in the conical thorax and the
subspherical abdomen. Cephalis hemispherical, with smaller pores and a spindle-shaped spiny
horn of twice the length. Feet cylindrical, as long as the abdomen, little divergent, their ends
curved outwards and thickened into a papillate knob.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c O08 ; breadth, a 0'03, I 0'07, c Oil.

Habitat. — Central Pacific, Station 265 to 272, depth 2425 to 2925 fathoms.

2. Podocyrtis attenuata, Ehrenberg.

Podocyrtis attenuata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xvi. fig. 5.

Shell nearly conical, gradually dilated from the apical to the basal part, with two slight
strictures. Surface a little rough. Length of the three joints = 2 : 3 : 4, breadth = 2: 4: 5. Pores
subregular, circular, equal, quincuncial. Cephalis subspherical, with a conical horn of twice the
length. Feet cylindrical, as long as the abdomen, little divergent (sometimes as in the specimen
figured, nearly parallel).

Dimensions. — Length of the three joints, a 0'015, b 0'03, c 0'04 ; breadth, a 0'02, b 0'04, c 0'05.

Habitat. — Fossil in Barbados.

3. Podocyrtis thyrsoceras, n. sp.

Shell slender, conical, smooth, very similar to Thyrsocyrtis rhizodon, Ehrenberg (1875, Abhandl.
d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii. fig. 1), with two slight strictures, nearly of the same
form and fenestration as in the preceding smaller species. Length of the three joints = 1:2: 3,
breadth = 1 : 3:4. Cephalis subspherical, with a large cylindrical straight horn, which reaches the
length of the abdomen, and is papillate in the distal half. Feet cylindrical, divergent, nearly as
long as the whole shell, broadened and spinulated at the distal end.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c OD6 ; breadth, a O02, b 0'06, c 0'08.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

4. Podocyrtis conica, n. sp.

Shell conical, without external strictures, but with two internal septal rings , Surface papillate.
Length of the three joints = 2:3: 8, breadth = 3:6: 10. Pores equal, subregular, circular,
quincuncial. Cephalis hemispherical, with a thick conical horn of the same length. Feet conical,
about as long as the thorax, divergent in the direction of the outline of the conical shell.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 0'08 ; breadth, a 00'3, b 0'06, c 01.

Habitat. — Cosmopolitan, Central Pacific, Stations 263 to 274 ; Tropical Atlantic, Station 348,
in depths between 2350 and 2925 fathoms ; also fossil in Barbados.

EEPORT ON THE RADIOLARIA. 1339

5. Podocyrtis corythceola, n. sp. (PL 72, fig. 2).

Shell ovate conical, with two deep strictures, and with rough surface. Length of the three joints
= 2 : 5:8, breadth = 3 : 8:10. Cephalis hemispherical, thorny, with a strong oblique horn three
times the length, which is armed with nine to twelve conical spines. Pores small, circular, of
irregular size and distribution. Feet spindle-shaped, divergent, as long as the inflated abdomen.

Dimensions. — Length of the three feet, a 0'02, b O05, c 0'08 ; breadth, a O03, b 0'08, c 01.

Habitat. — Indian Ocean, Maldive Islands (Haeckel), surface.

6. Podocyrtis surena, n. sp. (PL 72, fig. 10).

Shell thin-walled, tower-shaped, smooth, with two deep strictures. Length of the three joints
= 2 : 5 : 10, breadth = 3 : 10 : 11. Cephalis subspherical, with a bent conical horn, as long as the
hemispherical thorax. Abdomen cylindrical. Pores subregular, circular, quincuncially disposed, and
slightly larger in the abdomen. Feet with a thickened calf, nearly perpendicular, as long as the
thorax ; their distal ends little divergent, and forming a knob beset with small roundish tubercles.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 01 ; breadth, a 0'035, b 01, c Oil.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

7. Podocyrtis conulus, n. sp.

Shell elongate, conical, rough, without external strictures, but with two internal septal rings.
Length of the three joints = 3:4:15, breadth = 5:7:12. Cephalis hemispherical, with a thick
pyramidal horn of the same length. Feet also pyramidal, divergent, of the same size as the horn.
Pores irregular, roundish, of variable size. Abdomen very long.

Dimensions. — Length of the three joints, a 0'03, b 0'04, c 015 ; breadth, a 0'05, b 0'07, c 012.

Habitat. — Tropical Atlantic, Station 342, depth 1445 fathoms ; also fossil in Barbados.

8. Podocyrtis tridactyla, n. sp.

Shell conical, with two slight strictures, smooth. Length of the three joints = 2:6:5, breadth
= 4:5:6. Cephalis hemispherical, with a pyramidal horn of twice the length. Pores irregular,
polygonal, of variable size. Feet as long as the abdomen, constricted in the middle, trilobed at the
distal end ; the middle lobe twice as large as the lateral lobes.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'05 ; breadth, a 0'04, b 0'05, c 0'06.

Habitat. — Indian Ocean, Madagascar, Eabbe.

Subgenus 2. Podocyrtecium, Haeckel.

Definition. — Feet divergent (the distance between their ends being greater than that
between their bases). Pores of the thorax and abdomen of different form or size.

1340 THE VOYAGE OF H.M.S. CHALLENGER.

9. Podocyrtis prismatica, n. sp. (PI. 72, fig. 1).

Shell conical, rough, with two distinct strictures. Length of the three joints = 1:1:3, breadth
= 1:2:5. Cephalis subspherical, with a curved conical horn of twice the length. Thorax and
abdomen together nearly hemispherical. Pores small, regular, circular, quincuncial, twice as large in
the abdomen as in the thorax. Feet very large, twice as long as the whole shell, divergent, bent
outwards, prismatic, with strong prominent edges.

Dimensions. — Length of the three joints, a 0'02, I 0'02, c O'OG ; breadth, « OD2, b 0'04, c 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

10. Podocyrtis brevipes, Ehrenberg.

Podocyrtis brevipes, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xvi.
fig. 6.

Shell conical, smooth, with two slight strictures. Length of the three joints = 2:3:6, breadth
= 2:5:9. Cephalis subspherical, with a conical horn of the same length. Pores regular, circular,
quincuncial, three times as broad in the abdomen as in the thorax. Feet short, triangular, divergent,
as long as the horn. (The specimen figured by Ehrenberg was incomplete, one foot and the horn
being broken off.)

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 0'06 ; breadth, a 0'02, I O'Oo, c 0'09.

Habitat. — Fossil in Barbados.

11. Podocyrtis divergens, n. sp. (PL 72, fig. 6).

Shell slender, subconical, thick-walled, with two distinct strictures. Length of the three joints
= 2:5:7, breadth = 4 : 8 : 10. Cephalis hemispherical, with a large, oblique, prismatic horn three
times the length, and a small divergent by-horn at its base. Thorax hemispherical, rough, with
regular, circular, quincuncial pores. Abdomen cylindrical, thorny, with larger circular pores of
subregular disposition, two to three times as broad as those of the thorax. Feet conical, horn-like,
bent, as long as the abdomen ; strongly divergent in the distal half.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'07 ; breadth, a 0'04, b O'OS, c 01.

Habitat. — Western Tropical Pacific, Station 220, depth 1100 fathoms.

12. Podocyrtis collaris, Ehrenberg.

Podocyrtis collaris, ELrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xvi. fig. 1.

Shell conical, with slight collar and deeper lumbar stricture. Length of the three joints =
1:4:4, breadth = 1:4:8. Cephalis hemispherical, with a small oblique horn of the same length.
Pores regular, circular, quincuncial, four to six times as broad in the inflated abdomen as in the
conical thorax. Feet short and slightly divergent, little longer than the cephalis.

Dimensions.— Length of the three joints, a 0'02, b 0'07, c O'OS ; breadth, a 0'03, b O'OS, c 016.

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1341

13. Podocyrtis ventricosa, Ehrenberg.

Podocyrtis ventricosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xvi.

fig. 3.

Shell conical, with two deep strictures, thorny. Length of the three joints = 1:2:5, breadth =
1:4:8. Cephalis subspherical, with a small conical horn of the same length. Pores regular
circular, quincuncial, four to six times as broad in the inflated abdomen as in the hemispherical
thorax. (Pores much larger and less numerous than in the similar preceding species.) Feet broad
and stout, triangular, divergent, as long as the thorax.

Dimensions. — Length of the three joints, a O02, b 004, c 01 ; breadth, a 0'025, b 0'07, c 016.

Habitat. — Fossil in Barbados.

14. Podocyrtis flosculata, n. sp. (PI. 72, fig. 9).

Shell conical, rough, as broad as long, with distinct collar, but obliterated lumbar stricture.
Length of the three joints =1:2:4, breadth = 2:4:7. Cephalis hemispherical, with a thick
conical horn of the same length. Thorax truncate, conical, with small, circular, quincuncial pores.
Abdomen inflated, with very large and remarkable regular, quincuncial pores ; their inner edge
circular, the outer six-lobed, the six lobes elegantly alternating with six short conical spines. Feet
very coarse, equilateral triangular, half as broad as the thorax, little divergent.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'04, b 0'08, c 014.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

15. Podocyrtis centriscus, Ehrenberg,

Podocyrtis centriscus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xiv.

fig. 2.

Shell conical, rough, about as high as broad, with two obliterated strictures. Length of the
three joints = 1:2:4, breadth = 1:4:7. Cephalis small, hemispherical, with a stout conical horn.
Pores of the inflated abdomen irregular, roundish, very large, three occurring in the course of its
length, five times as broad as the small, very numerous, regular, circular pores of the conical thorax.
Feet S-shaped, as long as the abdomen, with the blunt end curved outwards.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'02, b 0'08, c 014.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms ; fossil in Barbados.

16. Podocyrtis magnified, n. sp. (PI. 72, fig. 5).

Shell conical, spiny, a little longer than broad, with two distinct strictures. Length of the three
joints = 1:2:5, breadth = 2:4:7. Cephalis hemispherical, with a large conical horn, which is as
long as the abdomen, nearly scaly, and covered with short, simple, and bifid spines. Pores
regular, circular, quincuncially disposed, four times as broad in the inflated abdomen as in the

1342 THE VOYAGE OF H.M.S. CHALLENGEE.

conical thorax. Spines of the former twice as large as those of the latter. Feet very long and
slender, cylindrical, S-shaped, bent outwards at the thickened distal end, with a spindle-shaped
papillate knob.

Dimensions. — Length of the three joints, a 0'03, b 0'04, c 01 ; breadth, a 0'04, b 0'08, c 014.

Habitat. — Canary Islands, Lanzerote, Haeckel, surface.

17. Podocyrtis princeps, Ehrenberg.

Podocyrtis princeps, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xiii.

fig. 1.

Podocyrtis princeps, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 540, Taf. xxxiii.
fig. 32.

Shell conical, with two distinct strictures. Length of three joints =1:2:5, breadth = 1:4:7.
Cephalis subspherical, with a large cylindrical, vertical horn, longer than the whole shell. Pores
regular, circular, quincuncial, in the inflated spiny abdomen very large (four to five in the course of
its length), five times as broad as in the smooth conical thorax. Feet about as long as the shell,
slightly bent, S-shaped, cylindrical.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 01 ; breadth, a 0'03, b 0'08, c 014.

Habitat.— Tropical Atlantic, Station 348, depth 2450 fathoms ; fossil in Barbados.

18. Podocyrtis euceros, Ehrenberg.

Podocyrtis euceros, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xv. fig. 1.

Shell conical, campanulate, with two deep strictures. Length of the three joints = 1:3:6,
breadth = 2:5:7. Cephalis hemispherical, with a large, cylindrical horn, nearly as long as the
shell. Pores regular, circular, hexagonally framed, quincuncial, four times as broad in the papillated,
inflated abdomen as in the hemispherical, smooth thorax. Feet short and broad, triangular, divergent,
about as long as the thorax. (In the specimen figured by Ehrenberg, two feet were broken off).

Dimensions. — Length of the three joints, a 0'016, b 0'05, c 01 ; breadth, a 0'03, b 0'08, c 012.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, and Pacific Oceans, at many stations,
and in various depths ; fossil in Barbados.

19. Podocyrtis cristata, n. sp. (PI. 72, fig. 7).

Shell conical-campanulate, thorny, with two deep strictures. Length of the three joints =
1:2:5, breadth = 2:4:7. Cephalis subspherical, with a large, oblique, little bent, conical horn, as
long as the abdomen. Thorax hemispherical, papillate, with small, regular, circular pores.
Abdomen inflated, with very large, circular pores, (three to four in its length), six times as broad as
those of the thorax, and separated by hexagonal, serrated crests. Feet cylindrical, stout, S-shaped,
slightly divergent, with a spherical papillate knob at the distal end.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 01 ; breadth, a 0'035, b 0'07, c 014.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

REPORT ON THE RADIOLARIA. 1343

20. Podocyrtis schomburgkii, Ehrenberg.

Podocyrtis schomburgkii, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 22; Abhandl. d. k. Akad.

d. Wiss. Berlin, 1875, p. 82, Taf. xiv. fig. 7.

Shell ovate-conical, with two distinct strictures. Length of the three joints = 2:5:10,
breadth = 3 : 8 : 12. Cephalis hemispherical, with a large, straight, conical horn as long as the
abdomen. Thorax campanulate, smooth, with small, regular, circular pores. Abdomen inflated,
papillate, with very large, regular, hexagonal pores (three to four in the course of its length), five
times as broad as their bars and as the pores of the thorax. Feet as long as the abdomen, nearly
parallel, slightly bent outwards at the conical distal end.

Dimensions. — Length of the three joints, a O02, b 0'05, c 01 ; breadth, a 0'03, b 0'08, c 012.

Habitat. — Fossil in Barbados.

21. Podocyrtis hexagonalis, n. sp.

Shell nearly ovate, slender, everywhere covered with a regular network of high, hexagonal, denti-
culated crests, separating the circular, funnel-shaped pores, which are twice as large in the sub-
spherical abdomen as in the hemispherical thorax, between both of which are two deep strictures.
Length of the three joints = 1:3:6, breadth = 2:5:6. Cephalis hemispherical, with a long and thin
cylindrical, vertical horn, as long as the abdomen. Feet of the same length and form, nearly
straight, slightly divergent.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 012 ; breadth, a 0'04, b O'Oll,
c 013.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

22. Podocyrtis ovata, n. sp.

Shell nearly ovate, papillate, without external strictures. Length of the three joints = 1:2:3,
breadth = 2:4:5. Cephalis hemispherical, with a pyramidal horn half as long as the shell. Pores
regular, circular, hexagonally framed, three times as broad in the inflated abdomen as in the conical
thorax. Feet pyramidal, little bent, divergent, about as long as the thorax.

Dimensions. — Length of the three joints, a 0'025, b 0'05, c 0'08 ; breadth, a 0'05, b 0'095, e 012.

Habitat. — Mediterranean, Corfu, Haeckel, surface.

23. Podocyrtis urceolata, n. sp.

? Podocyrtis mitra, Bury, 1862, Polycystins of Barbados, pi. v. fig. 3.

Shell nearly ovate, smooth, with two deep strictures. Length of the three joints = 1:2:6,
breadth = 2:4:5. Cephalis subspherical, with a stout, conical horn of the same length. Thorax
flat, hemispherical, with four to six transverse rows of small circular pores. Abdomen urceolate,

1344 THE VOYAGE OF H.M.S. CHALLENGER.

with four to five transverse rows of very large, subregular, hexagonal pores. Feet short and thick,
bent outwards, as long as the thorax.

Dimensions. — Length of the three joints, a 0'025, b 0'05, c 015 ; breadth, a 0'05, b 01, c 013.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; fossil in Barbados.

24. Podocyrtis ehrenbergii, Haeckel.

Podocyrtis ampMacantha, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf.

xvii. fig. 3.

Shell slender, ovate, smooth, with deep collar, but evanescent lumbar stricture. Length of the
three joints = 1:3:2, breadth = 1:3:3. Cephalis subspherical, with a large conical horn, as long
as the campanulate thorax. Abdomen nearly cylindrical. Pores irregular, roundish, two to four
times as large in the abdomen as in the thorax. Feet conical, slender, divergent, nearly as long as
the shell. (In the imperfect specimen figured by Ehrenberg, two spines were broken off.)

Dimensions. — Length of the three joints, a 0'02, I 0'06, c 0'04 ; breadth, a 0'02, b 0'06, c 0'06.

Habitat. — North Pacific, Station 253, depth 3125 fathoms ; fossil in Barbados.

25. Podocyrtis argulus, Ehrenberg.

Podocyrtis argulus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80, Taf. xvi. fig. 2.

Shell slender, ovate, or subconical, with two deep strictures. Length of the three joints =
1:2:4, breadth = 1:3:4. Cephalis hemispherical, with a small conical horn of the same length
(broken off in the figure of Ehrenberg). Pores regular, circular, three times as broad in the inflated
abdomen as in the campanulate thorax. Feet spindle-shaped, slender, divergent, about as long as
the thorax.

Dimensions. — Length of the three joints, a 0'025, b 0'05, c 01 ; breadth, a 0'03, b 0'07, c 01.

Habitat. — Tropical Atlantic, Station 247, depth 2530 fathoms ; also fossil in Barbados.

Subgenus 3. Podocyrtidium, Haeckel.

Definition. — Feet convergent (the distance between their ends being smaller than
that between their bases). Pores of the thorax and abdomen nearly equal in size and
similar in form.

26. Podocyrtis papalis, Ehrenberg.

Podocyrtis papalis, Ehrenberg, Mikrogeol., Taf. xxxvi. fig. 23 ; Abhandl. d. k. Akad. d.
Wiss. Berlin, 1875, p. 82, Taf. xv. fig. 6.

Shell ovate, smooth, without external stricture. Length of the three joints = 1:3:1,
breadth = 1:3:3. Cephalis ovate, with a stout pyramidal horn of twice the length. Thorax and

REPORT ON THE RADIOLARIA. 1345

abdomen with about thirty longitudinal, divergent ribs, separating the same number of longitudinal
rows of regular, circular pores, the size of which increases gradually towards the base. Feet shovel-
shaped (broad, triangular, with convex outer and concave inner side, the obtuse end being curved
inwards), about as long as the short abdomen, only slightly convergent.

Dimensions. — Length of the three joints, a 0'04, b 012, c O04; breadth, a 0'04, b 012, c Oil.

Habitat. — Fossil in Barbados.

27. Podocyrtis costata, n. sp.

Shell ovate, smooth, of the same form and structure as Podocyrtis papalis, but with two
distinct strictures and different proportions. Length of the three joints =1:3:6, breadth
= 2:4:6. About thirty longitudinal ribs regularly alternating with rows of circular, regular
pores. Feet as in Podocyrtis papalis.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 012 ; breadth, a 0'04, b 0'08, c 012.

Habitat. — Central Pacific, Stations 266 to 272, depth 2425 to 2925 fathoms.

28. Podocyrtis mitrella, Ehrenberg.

Podocyrtis mitrella, Ehrenberg, 1875, Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 82, Taf. xv. fig. 3.

Shell ovate, smooth, nearly of the same form and structure as Podocyrtis papalis, but different
in the proportions of the joints, in the much smaller, regular pores, and in the great breadth of the
shovel-shaped, blunt, about semicircular feet. Length of the three joints = 2:9:4, breadth =
3:10:3. Cephalis subspherical, with a thick pyramidal horn of the same length. Slight collar, but
no lumbar stricture.

Dimensions. — Length of the three joints, a 0'02, b 0'09, c 0'04 ; breadth, a 0'03, b 01, c 0'03.

Habitat. — Fossil in Barbados.

29. Podocyrtis mitra, Ehrenberg.

Podocyrtis mitra, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 20; Abhandl. d. k. Akad. d. Wiss.
Berlin, 1875, p. 82, Taf. xv. fig. 4.

Shell ovate, conical, smooth, with two slight strictures. Length of the three joints = 1:2:3,
breadth = 1:3:4. Cephalis with the horn (of equal length) conical. Pores regular, circular, in
about twenty longitudinal rows, slightly increasing in size in the middle part of the abdomen. Feet
shovel-shaped, blunt, slightly divergent, only as long as the cephalis.

Dimensions. — Length of the three joints, a 0'025, b 0'5, c 0-7 ; breadth, a 0'03, 6 0'075, c 01.

Habitat. — Cosmopolitan; Mediterranean (Gibraltar), Canaiy Islands, Central Pacific, Stations
265 to 274, in different depths ; also fossil in Barbados.

(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 169

1346 THE VOYAGE OF H.M.S. CHALLENGER.

i

30. Podocyrtis argus, Ehrenberg.

Podocyrtis argus, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xvi. fig. 9.

Shell ovate, with two distinct strictures, smooth. Length of the three joints =1:3:4,
breadth = 1:4:5. Cephalis subconical, with a conical horn of the same length. Thorax cam-
panulate. Abdomen inflated. Pores subregular, roundish, of nearly equal breadth, quincuncial.
Feet shovel-shaped, triangular, nearly vertical, only as long as the cephalis.

Dimensions. — Length of the three joints, a 0'02, I 0'06, c 0'08 ; breadth, a 0'025, I 008, c 01.

Habitat. — Tropical Atlantic, Station 347, surface ; fossil in Barbados.

31. Podocyrtis eulophos, Ehrenberg.

Podocyrtis eulopJios, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xiv. fig. 6.

Shell subconical, slender, with two slight strictures, smooth. Length of the three joints =
1:2:6, breadth = 2:4:6. Cephalis hemispherical, with a large, spindle-shaped, angular horn of
twice the length. Thorax hemispherical. Abdomen truncate, conical. Pores subregular, roundish,
in about twenty longitudinal rows, their breadth gradually increasing towards the base. Feet
shovel-shaped, blunt, nearly vertical, only as long as the cephalis.

Dimensions. — Length of the three joints, a 0'025, b 0'05, c 016 ; breadth, a 0'05, b O'OS, c 014.

Habitat. — Fossil in Barbados.

32. Podocyrtis favosa, n. sp.

Shell ovate, with two slight strictures, and with honeycomb-like surface. Length of the three
joints =1:5:2, breadth = 2:6:5. Cephalis hemispherical, with a pyramidal horn of twice the
length. Thorax hemispherical. Pores regular, circular, hexagonally framed, funnel-shaped, with
high, prominent crests between them. Feet shovel-shaped, little convergent, triangular, as long as
the abdomen.

Dimensions. — Length of the three joints, a 0-02, b 01, c 0'04 ; breadth, a 0'04, b 012, c Oil.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

33. Podocyrtis fusiformis, n. sp.

Shell slender, nearly spindle-shaped, diminishing gradually from the broadest middle part
(immediately above the lumbar septum) towards the two poles. Length of the three joints =
1:5:8, breadth = 2:6:5. Cephalis subspherical, with a large conical horn three times the length.
Thorax and abdomen with twenty-four to thirty denticulated, longitudinal ribs, separating the same
number of longitudinal rows of regular, circular pores. Instead of the lumbar stricture, a broad,
internal septum occurs. Feet slender, straight, as long as the abdomen, only slightly convergent.

Dimensions. — Length of the three joints, a 0'03, b 01, c 016 ; breadth, a 0'05, b 012, c 01.

Habitat. — Indian Ocean, Madagascar (Eabbe) surface.

EEPORT ON THE RADIOLARIA. 1347

Subgenus 4. Podocyrtonium, Haeckel.

Definition. — Feet convergent (the distance between their ends being smaller than
that between their bases). Pores of the thorax and abdomen different in size or form.

34. Podocyrtis pedicellaria, n. sp. (PL 72, fig. 8).

Shell conical, ovate, -with two very slight strictures. Length of the three joints = 2:3:8,
breadth = 2:4:8. Cephalis conical, with a pyramidal horn of the same length. Pores subregular,
circular, quincuncially disposed, two to three tunes as broad in the smooth abdomen as in the
rough, spinulate thorax. Feet as long as the thorax, shovel-shaped (broad, triangular, with convex
outer and concave inner side, the free ends being curved inwards), only slightly convergent.

Dimensions. — Length of the three joints, a 0'04, b 0'05, c 016 ; breadth, a 0'05, I 0'09, c 016.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

35. Podocyrtis sinuosa, Ehrenberg.

Podocyrtis sinuosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xv. fig. 5.
Podocyrtis sinuosa, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 540, Taf. xxxiii. fig. 33.

Shell slender, conical, with slight collar, but without lumbar stricture. Length of the three
joints = 1:2:4, breadth = 1:2:4. Cephalis subspherical (in the figure of Ehrenberg broken off),
with a pyramidal horn of the same length. Pores subregular, circular, four times as broad in the
abdomen as in the thorax. Feet shovel-shaped, as long as the thorax.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 012 ; breadth, a 0'03, b 0'06, c 012.

Habitat. — Fossil in Barbados.

36. Podocyrtis floribunda, n. sp.

Shell ovate, conical, with two very slight strictures. Length of the three joints =2 : 3 : 6,
breadth = 2:4:7. Between twenty-four to thirty longitudinal, denticulated ribs lie the same
number of subregular pores, which are flower-like, lobed, or rosette-shaped, and two to three tunes
as large in the abdomen as in the thorax. Feet shovel-shaped (as in the similar Podocyrtis
pedicellaria (PL 72, fig. 8).

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 012 ; breadth, a 0'04, b 0'08, c 014.

Habitat. — Tropical Atlantic, Station 342, depth 1445 fathoms ; also fossil in Barbados.

37. Podocyrtis scaphopodia, n. sp.

Shell conical, rough, with two slight strictures. Length of the three joints =2:3:5, breadth
= 2:4:8. Cephalis subspherical, with a pyramidal horn of twice the length. Pores subregular,

1348 THE VOYAGE OF H.M.S. CHALLENGER.

circular, quincuncial, four times as large in the abdomen as in the thorax. Feet short and broad,
triangular, shovel-shaped, with convergent ends. This species is similar to Podocyrtis brevipes, but
differs in the form and size of the horn and of the feet.

Dimensions. — Length of the three joints, a 0'02, I 0'03, c 0'05 ; breadth, a 0'02, b 0'04, c 0'08.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

38. Podocyrtis lithoconus, n. sp. (PL 72, fig. 3).

Shell conical, thick-walled, smooth, with two slight strictures. Length of the three joints =
2:3:6, breadth = 2:4:7. Cephalis hemispherical, with a spindle-shaped horn of the same length.
Pores subregular, circular, two to four times as broad in the abdomen as in the thorax. Feet
triangular, shovel-shaped, nearly vertical, as long as the cephalis.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 012 ; breadth, a 0'04, b 0'08, c 014.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

39. Podocyrtis ampla, Ehrenberg.

Podocyrtis ampla, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80,Taf. xvi. fig. 7.

Shell conical, thick-walled, with distinct collar, but without lumbar stricture. Length of the
three joints = 1:4:5, breadth = 1:6:7. Cephalis hemispherical, with a large conical horn, as long
as the thorax. Pores regular, circular, quincuncial, three times as broad in the rough abdomen as
in the smooth thorax. Feet very small, shovel-shaped, only as long as the cephalis.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 01 ; breadth, a 0"03, I 012, c 014.

Habitat. — North Atlantic (Florida) ; also fossil in Barbados.

40. Podocyrtis nana, Ehrenberg.

Podocyrtis nana, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xvii. fig. 2.

Shell conical, thorny, with two distinct strictures. Length of the three joints = 1:3:3,
breadth = 2:5:6. Cephalis hemispherical, with a large cylindrical horn, nearly as long as the
shell. Pores in the abdomen irregular, roundish, two to four times as broad as the regular,
circular, quincuncial pores of the thorax. Feet very small, shovel-shaped, scarcely as long as the
cephalis.

Dimensions. — Length of the three joints, a O'Ol, b 0'03, c OD3 ; breadth, a 002, b 0'05, c 0'06.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms ; also fossil in Barbados.

41. Podocyrtis lycea, Haeckel.

Thyrsocyrtis lycea, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii. fig. 3.

Shell ovate, conical, with two deep strictures. Length of the three joints = 2:5:8, breadth
= 3:8:9, Cephalis hemispherical, with a large conical horn, which is spinulate, scaly, and as

REPORT ON THE RADIOLARIA. 1349

long as the abdomen. Pores subregular, circular, two to four times as broad in the smooth abdomen
as in the spiny thorax. Feet very short and broad, shovel-shaped, scarcely as long as the
cephalis.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 008 ; breadth, a 0'03, b 0'08, c 0'09.

Habitat. — Fossil in Barbados.

42. Podocyrtis bromia, Haeckel.

Thyrsocyrtis bromia, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii.
fig. 2.

Shell ovate, thorny, with two distinct strictures. Length of the three joints = 2:5:5, breadth
= 3:8:9. Cephalis subspherical, with a large conical horn, which is half as long as the shell, and
spirally dentated in the distal half. Thorax conical, spinulate, with regular, circular, quincuncial
pores. Abdomen tuberculate, with a small number of very large irregular pores. Feet short,
shovel-shaped, nearly vertical, as long as the cephalis.

Dimensions. — Length of the three joints, a 0*02, I 0'05, c 0'05 ; breadth, a 0'03, 1 0'08, c 0'09.

Habitat. — Fossil in Barbados.

43. Podocyrtis sphcerogaster, n. sp.

Shell inversely ovate, with two deep strictures. Length of the three joints = 1 : 2 : 6, breadth
= 2:4:7. Cephalis hemispherical, with a slender, slightly bent horn, as long as the abdomen.
Thorax hemispherical, spinulate. Abdomen nearly spherical, with much constricted mouth. Pores
subregular, circular, hexagonally framed. Feet slender, cylindro-conical, about as long as the
shell, with outer convexity, distinctly convergent.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 012 ; breadth, a O04, b 0'08, c 014.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

44. Podocyrtis tripus, Haeckel.

Podocyrtis bicornis, Ehrenberg, 1875, Abhandl. d. k. A.kad. d. Wiss. Berlin, p. 80, Taf. xvi.

fig. 8.
\Podocyrtis dipus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xii. fig. 11.

Shell conical, rough, with two deep strictures. Length of the three joints = 1:2:4; breadth
= 1:3:5. Cephalis subspherical, with a large, oblique, conical horn (sometimes with a small acces-
sory horn at its base), Thorax hemispherical, with subregular, circular, small, quincuncial pores.
Abdomen campanulate, with a small number (about twenty) of very large, irregular, polygonal pores.
Feet conical, small, as long as the thorax, slightly convergent or nearly vertical.

Dimensions. — Length of the three joints, a 0'02, 6 0'04, c 0'08 ; breadth, a 0'03, b 0'06, c 01.

Habitat. — Fossil in Barbados.

1350 THE VOYAGE OF H.M.S. CHALLENGER.

45. Podocyrtis triacantha, Ehrenberg.

Podocyrtis triacantha, Ehrenberg, 1875, Abhaudl. d. k. Akad. d. Wiss. Berlin, Taf. xiii. fig. 4.

Shell conical, rough, with two distinct strictures. Length of the three joints =1:2:4; breadth
= 2:4:6. Cephalis hemispherical, with a very large conical horn, nearly as long as the whole
shell Thorax campanulate, densely spinulate, with very small, regular, circular, quincuncial pores.
Thorax inflated, with very large, irregular, roundish, pores (three to four in the course of its length),
five to ten times as broad as those of the thorax. Feet slender and thin, subcylindrical, as long as
the abdomen, divergent in the proximal half, convergent and curved inwards in the distal half.
Dime'nsions.- Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'04, b 0'08, c 012.
Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

Genus 593. Thyrsocyrtis,^ Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 54.

Definition. — Th eopilida (vel Tricyrtida triradiata aperta) with three branched
terminal feet on the mouth of the abdomen, without lateral ribs or wings. Apex with a
horn, which usually bears lateral spines.

The genus Thyrsocyrtis differs from the preceding Podocyrtis, its ancestral form, in
the ramification of the three terminal feet, which in the latter genus remain simple.

1. Thyrsocyrtis rhizodon, Ehrenberg.

Thyrsocyrtis rhizodon, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, Taf. xii. fig. 1.

Shell slender, conical, smooth, with two distinct strictures. Length of the three joints =
1:2:3, breadth = 1:3:4. Cephalis hemispherical, with a large cylindrical horn, reaching half the
length of the shell, and papillate in the distal half. Pores nearly equal, regular, circular, quin-
cuncially disposed, small Feet divergent, about half as long as the shell, broadened and forked at
the distal end. (The fork incision is often much deeper, as in the figure given by Ehrenberg.)

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'06 ; breadth, a 0'03, b 0'06, c 0'08.

Habitat. — Fossil in Barbados.

2. Thyrsocyrtis arborescens, n. sp. (PL 68, fig. 9).

Shell nearly ovate, thorny, with a deep collar, but without lumbar stricture. Length of the
three joints = 1:2:4, breadth = 2 : 3:4. Cephalis hemispherical, with a stout scaly or branched
horn, half as long as the shell. Pores irregular, roundish, small, separated by spinulated crests,
of slightly different sizes. Feet divergent, cylindrical, and as long as the thorax in the proximal half,

1 Thyrsocyrtis — Basket with a thyrsus or apical rod ;

REPORT ON THE RADIOLARIA. 1351

irregularly branched or arborescent in the distal half, with ten to thirty blunt, thickened or
papillate, terminal branches.

Dimensions. — Length of three joints, a O02, b 0'04, c O08 ; breadth, a 0'04, b 0'06, c O08.

Habitat. — Central Pacific, Station 268, depth, 2900 fathoms.

3. Thyrsocyrtis furcata, n. sp.

Shell ovate, thorny, with two slight strictures. Length of the three joints = 1:1:3, breadth =
1:2:3. Cephalis hemispherical, with a pyramidal smooth horn of twice the length. Pores of the
thorax and abdomen nearly equal, regular, circular, quincuncial. Feet very broad, forked, about as
long as the abdomen, much divergent ; the outer fork-branch as long as the simple basal half of the
foot, and twice as long as the inner or axial branch.

Dimensions. — Length of the three joints, a 0'03, b 0'03, c 0'09 ; breadth, a 0'04, b 0'06, c 0'09.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

4. Thyrsocyrtis rhizopus, Haeckel.

Podocyrtis rhizodon, Ehrenberg, 1875, Abhandl. d. k. Akad. d. "VViss. Berlin, p. 82, Taf. xv. fig. 2.

Shell pear-shaped, smooth, with two slight strictures. Length of the three joints — 1:2:4,
breadth = 1:3:5. Cephalis ovate, with a stout, sword-shaped horn of the same length. Pores
regular, circular, twice as broad in the inflated abdomen as in the truncate, conical thorax. Feet
cylindrical, parallel, vertical, straight, divided at the distal end into two short fork -branches.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'02, b 0'06, c 01.

Habitat. — Fossil in Barbados.

5. Thyrsocyrtis rhizopodium, n. sp. (PI. 68, fig. 8).

Shell campanulate-conical, with deep collar, but without lumbar stricture. Length of the
three joints = 3 : 4 : 10, breadth = 4 : 10 : 15. Cephalis subspherical, with a small conical horn of
the same length. Pores regular, circular, quincuucial, three to four times as large in the inflated
abdomen as in the truncate, conical thorax. Feet cylindrical, slightly divergent, about as long as
the abdomen, S-shaped, bent outwards, irregularly branched in the distal half, with tuberculate
terminal branches.

Dimensions. — Length of the three joints, a 0'03, b 0'04, c 01 ; breadth, a 0'04, b 01, c 015.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

6. Thyrsocyrtis radicata, Haeckel.

Podocyrtis radicata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xiii.
fig. 5.

Shell campanulate-conical, with two distinct strictures. Length of the three joints = 1:2:4,
breadth = 1:4:6. Cephalis subspherical, with a small conical horn of half the length. Pores regular,

1352 THE VOYAGE OF H.M.S. CHALLENGER.

circular, quincuncial, four to five times as broad in the inflated, rough abdomen as in the campanu-
late, smooth thorax. Feet cylindrical, nearly as long as the whole shell, S-shaped, bent outwards,
dilated and hand-shaped at the distal end, divided by three to five incisions in some irregular
finger-like branches.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth a 0'03, b 0'08, c 012.

Habitat. — Fossil in Barbados.

7. Thyrsocyrtis trifida, n. sp.

Shell campanulate-conical, thorny, with two slight strictures. Length of the three joints =
1:2:3, breadth = 1:3:5. Cephalis subspherical, with a short pyramidal horn of the same length.
Pores regular, circular, hexagonally framed, twice as broad in the inflated spiny abdomen as in the
rough, campanulate thorax. Feet very large, as long as the shell, cylindrical in the proximal
simple half, in the distal half broadened and cleft into three large, irregularly lobed branches,
two shorter lateral, and one longer abaxial branch ; the latter forms the prolongation of the
proximal half. The outer straight edges of the three diverging feet correspond to the edges of a
three-sided pyramid.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c O09 ; breadth, a 0'03, b 0'09, c 015.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Genus 594. Dictyopodium,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — T heopilida (vel Tricyrtida triradiata aperta) with three latticed
terminal feet on the mouth of the abdomen, without lateral ribs or wings. Apex with
a horn.

The genus Dictyopodium differs from the two preceding ancestral genera in the
fenestration of the three terminal feet, which in Podocyrtis are simple, in Thyrsocyrtis
branched, but not latticed.

1. Dictyopodium eurylophus, Ehrenberg.

Dictopodium eurylophus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68,

Taf. xix. fig. 4.

Shell campanulate-conical, thorny, with two deep strictures. Length of the three joints =
1:2:3, breadth = 1:3:4. Cephalis hemispherical, with a stout angular horn of twice the length,
which at the apex is broadened and divided into some spines. Pores in the hemispherical thorax
and in the truncate, conical abdomen of nearly equal size, small, subregular, circular (in the

1 Dictyopodium = Shell with latticed feet ; linrvoa,

REPORT ON THE RADIOLARIA. 1353

abdomen sometimes more irregular and unequal). Feet as long as the abdomen, arising from it
with triangular base, diverging, fenestrated throughout the entire length.

Dimensions. — Length of the three joints, a 0'03, b O06, c O08 ; breadth, a 0'03, b 0'08, c 01.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms; fossil in Barbados.

2. Dictyopodium oxylophus, Ehrenberg.

Dictyopodium oxylophus, Ehreuberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68,
Taf. xix. fig. 5.

Shell subconical, smooth, with two slight strictures. Length of the three joints = 2 : 5 : 7,
breadth = 3:8:10. Cephalis subspherical, with a small, conical, smooth horn of the same length.
Pores irregular, polygonal, roundish, slightly larger in the abdomen than in the thorax. Feet as long
as the thorax, arising from it with triangular base, diverging, fenestrated throughout the entire length.
(The figures of this and the preceding species given by Ehrenberg are incomplete, having been
drawn from spoiled specimens. In perfect specimens all the three feet are present and diverge
in both species in the direction of the conical outline. The main difference between the two
species is connected with the pores, which in Dictyopodium oxylophus are larger and more irregular,
the two strictures are here not so deep.)

Dimensions. — Length of the three joints, a 0'02, b 0-05, c 0'07 ; breadth, a 0'03, b 0'08, c 01.

Habitat. — Fossil in Barbados.

3. Dictyopodium scaphopodium, n. sp. (PI. 73, fig. 8).

Shell campanulate, conical, with two deep strictures. Length of the three joints = 1:2:6,
breadth = 1:4:8. Cephalis hemispherical, with a conical, smooth horn of twice the length.
Thorax hemispherical, rough, with small, regular, circular pores. Abdomen inflated and papillate,
with very large, polygonal or roundish pores (eight to ten times as broad as the thoracic pores)
Feet divergent, nearly as long as the shell, S-shaped, bent outwards, solid and cylindrical in the
proximal half, shovel-shaped and fenestrated in the distal half.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 012 ; breadth, a 0-025, b O'OS, c 016.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

4. Dictyopodium cothurnatum, Haeckel.

Podocyrtis cothurnata, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. B. 21 ; Abhandl. d. k. Akad.

d. Wiss. Berlin, 1875, p. 82, Taf. xiv. fig. 1.
Anthocyrtis cothurnata, Haeckel, 1862, Monogr. d. Radiol., p. 310.

Shell subconical, rough, with two deep strictures. Length of the three joints = 1:2:3,
breadth = 1:3:5. Cephalis hemispherical, with a very large cylindrical, vertical horn, about as
long as the whole shell. Thorax conical, rough, with small, regular, circular pores. Abdomen
inflated, with very large, roundish pores (four to five in the course of its length), six to eight times

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Er 170

1354 THE VOYAGE OF H.M.S. CHALLENGER.

as large as the thoracic pores. Feet nearly vertical, only slightly divergent, S-shaped, bent, as
long as the abdomen, cylindrical ; at the distal end shovel-shaped and fenestrated (often much
more than in Ehrenberg's figure).

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 01 ; breadth, a 0'03, b 0'09, c 015.

Habitat. — Fossil in Barbados.

5. Dictyopodium thyrsolophus, n. sp. (PL 73, fig. 7).

Shell subconical, rough, with two slight strictures. Length of the three joints = 1:2:4,
breadth = 1:3:6. Cephalis hemispherical, with an elegant horn, which is half as long as the shell,
spindle-shaped and scaly on the distal third. Thorax hemispherical, with small, regular,
circular pores. Abdomen inflated, papillate, with regular, circular pores, three times as large as
the thoracic pores (five to six in the course of its length). Feet slightly divergent, cylindrical, about
as long as the shell, shovel-shaped and fenestrated (with a prominent middle rib) at the distal end.

Dimensions. — Length of the three joints, a O'OS, b 0'06, c 012 ; breadth, a 0'04, b 01, c 018.

HaUtat. — Central Pacific, Station 268, depth 2900 fathoms.

Subfamily 2. THEQPERIDA, Haeckel, 1881, Prodromus, p. 436.

Definition. — P odocyrtida with the basal mouth of the shell fenestrated (vel
Tricyrtida triradiata clausa).

Genus 595. Lithornithium? Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 54.

Definition. — T heoperida (vel Tricyrtida triradiata clausa) with three solid lateral
wings on the thorax.

The genus Lithornithium has an ovate or spindle-shaped shell, with two distinct
strictures, and tapering towards both poles. The abdomen is simple, whilst the
c.ephalis bears an apical horn, and the thorax three free, lateral, solid, divergent wings.
It may be derived from Pterocorys by development of a terminal lattice-plate closing
the mouth.

1. Lithornithium ciconia, n. sp. (PI. 67, fig. 3).

Shell nearly spindle-shaped, with two indistinct strictures. Length of the three joints =
1:2:4, breadth =1:3:3. Cephalis ovate, with a large pyramidal spine of twice the length.
Thorax three-sided pyramidal with three pyramidal wings of the same length, the broad triangular
bases of which occiipy the whole length of the thoracic edges. Abdomen inversely ovate (in the

1 Litfiornithium=Si\iceo\w bird ; X/tfo;, i

REPORT ON THE RADIOLARIA. 1355

I

figured specimen broken off, in another specimen, found afterwards, completely closed at the distal
end). Pores very small, regular, circular, of equal size.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'02, I 0'06, c 0'06.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

2. Lithornithium falco, n. sp. (PI. 67, fig. 1).

Shell nearly ovate, with two sharp strictures. Length of the three joints = 1:3:4, breadth =
1:4:3. Cephalis hemispherical, with a conical spine of the same length. Thorax subspherical,
with three conical wings of half the length, little curved, arising with broad triangular base from
the upper half of the thorax. Abdomen inversely conical. Pores irregular, roundish, of different
sizes.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'07 ; breadth, a 0'03, b 0'08, c 0'06.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Lithornithium trochilus, n. sp. (PI. 67, fig. 4).

t

Shell nearly spindle-shaped, with two deep strictures. Length of the three joints = 1:2:3,
breadth = 1:3:2. Cephalis hemispherical, with a thin curved horn of the same length. Cephalis
subovate, with three thin curved wings of half the length, arising with broad base from its upper
half. Abdomen ovate. Pores subregular, circular, of slightly different sizes.

Dimensions. — Length of the three joints, a 0'015, b 0'5, c 0-06 ; breadth, a 0'02, b 0-05, c 0'04.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

4. Lithornithium foveolatum, Ehrenberg.

Liihamithium foveolatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf.
iv. fig. 7.

Shell subovate, with two distinct strictures. Length of the three joints = 2:4:3, breadth =
3:5:4. Cephalis hemispherical, with a short conical spine of the same length. Thorax sub-
spherical, with three broad triangular wings of half the length arising from its lower half. Abdomen
subconical. Pores small, regular, circular, of nearly equal size.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'03 ; breadth, a 0'03, b 0'05, c 0'04.

Habitat. — Fossil in Barbados.

5. Lithornithium fringilla, n. sp. (PI. 67, fig. 2).

Shell ovate, with two slight strictures. Length of the three joints = 4:7:4, breadth = 3:7:5.
Cephalis ovate, with a pyramidal spine of the same length Thorax subconical, with three stout

1356 THE VOYAGE OF H.M.S. CHALLENGER.

conical, curved wings of half the length, arising from its lower third (immediately above the girdle).
Abdomen inversely campanulate. Pores subregular, circular, of equal size.

Dimensions. — Length of the three joints, a 0'04, I 0'07, c 0'04 ; breadth, a 0'03, b 0'07, c 0'05.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Lithornithium hirundo, Ehrenberg.

Lithocampe hirundo, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 65.
Lithornithium hirundo, Ehrenberg, 1854, Mikrogeol., Taf. xix. fig. 53.

Shell nearly ovate, with two deep strictures. Length of the three joints = 2:6:4, breadth =
2:7:5. Cephalis hemispherical, with an oblique, conical horn of twice the length. Thorax
hemispherical, with three long, angular, little divergent wings of twice the length, which are S-shaped,
curved, and arise from its lower third, immediately above the girdle. Abdomen inversely conical.
Pores irregular, roundish, of different sizes. In the figure of Ehrenberg the abdomen is broken off;
in a specimen from Caltanisetta, with somewhat shorter and broader wings, I found it complete.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'04; breadth, a 0'02, b 0'07, c 0'05.

Habitat. — Fossil in Tertiary rocks of the Mediterranean (^Egina, Greece ; Caltanisetta, Sicily).

Genus 596. Sethornithium,1 Haeckel, 1881, Prodromus, p. 436.

Definition. — T heoperida (vel Tricyrtida triradiata clausa) with three latticed
lateral wings on the thorax.

The genus Sethornithium differs from the preceding Lithornithium, its ancestral
form, only in the fenestration of the three thoracic wings, and bears therefore to it the
same relation that Dictyoceras exhibits to Pterocorys.

1. Sethornithium dictyopterum, n. sp.

Shell ovate, with two slight strictures. Length of the three joints = 2:4:3, breadth = 1:5:4.
Cephalis ovate, with a pyramidal horn of twice the length. From the middle part of the thorax
arise three broad, triangular, latticed wings of about the same length, the distal end of each of which
is curved downwards. Abdomen inversely conical. Pores regular, circular. (Similar to Lithornithium
fringilla, PI. 67, fig. 2, but with much larger wings, which in the greater part are fenestrated.)

Dimensions. — Length of the three joints, a 0'04, b 0'08, c 0'06 ; breadth, a 0'02, b O'l, c 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

1 Sethornithium** Latticed bird; eqia,

REPOKT ON THE RADIOLARIA. 1357

Genus 597. Theopera,1 Haeckel, 1881, Prodromus, p. 436.

Definition. — T heoperida (vel Tricyrtida triradiata clausa) with three lateral
wings, beginning from the sides of the thorax and prolonged into the sides of the
abdomen.

The genus Theopera differs from the two preceding genera in the greater extension
of the three lateral wings, which are prolonged from their original base, the thorax, into
the inversely conical abdomen. It has therefore an intermediate position between the
preceding and the following genera. It differs from the similar Pterocanium and
Theopodium in the closure of the constricted and fenestrated mouth.

1. Theopera prismatica, n. sp. (PI. 67, fig. 7).

Rhopalocanium prismaticum, Haeckel, 1 879, Atlas, pL Ixvii. fig. 7.

Shell three-sided prismatic, with three broad and long hyaline wings, which are prolonged from
the collar stricture almost to the basal end, with three parallel edges. Length of the three joints
= 2:8:10, breadth = 3:9:8. Cephalis hemispherical, with a conical horn of the same length.
Thorax subspherical ; abdomen inversely ovate ; pores of both small, regular, circular, of equal size.

Dimensions. — Length of the three joints* a 0'02, I 0'08, c O'l ; breadth, a 0-03, b 0'09, c 0'08.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

2. Theopera pyramis, Haeckel.

Rliopalocanium sp., Bury, 1862, Polycystins of Barbados, pi. xvii. fig. 8.

Shell three-sided pyramidal, with three broad and long hyaline wings, which are prolonged from
the collar stricture almost to the basal end, with three diverging edges. Length of the three joints
= 3:8:11, breadth = 4 : 8 : 9. Cephalis subspherical, with a conical horn of the same length.
Thorax hemispherical ; abdomen inversely campanulate. Pores in the abdomen twice to three
times as broad as in the thorax, subregular, circular. Differs from the preceding species mainly in
the broader pyramidal form and the divergence of the wings.

Dimensions. — Length of the three joints, a 0'03, 6 0'08, c Oil ; breadth, a 0'04, 6 0'08, c 0'09.

Habitat. — Fossil in Barbados.

3. Theopera fusiformis (PI. 67, fig. 5).

Shell nearly spindle-shaped, rough, with two slight strictures. Length of the three joints =
2:3:6, breadth = 2:5:4. Cephalis hemispherical, large, with an oblique conical horn of the same
length. Thorax hemispherical ; abdomen inversely conical. ^Pores irregular, roundish, of very

1 Theopera - Divine pouch ; 616;,

1358 THE VOYAGE OF H.M.S. CHALLENGER.

different sizes,. Three wings short, broad, diverging, triangular, and striated, embracing at the base
the lumbar stricture, the lower third of the thorax and the upper third of the abdomen.

Dimensions. — Length of the three joints, a 0'04, b 0'06, c 012 ; breadth, a 0'045, b 01, c 0'08.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

4. Theopera luscinia, Haeckel.

Lithornithium luscinia, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 78, Taf. iv.
fig. 9.

Shell slenderly ovate, with distinct collar, but indistinct lumbar strictures. Length of the three
joints = 1:3:6, breadth = 1:5:5. Cephalis hemispherical, with a slender cylindrical horn of three
times the length, bearing a spindle-shaped spinulate top (like a fir-cone). Pores subregular, circular,
twice as broad in the abdomen as in the thorax. Three wings arising with broad triangular base,
embracing the lower third of the thorax and the upper third of the abdomen, prolonged into three
slender diverging spines, as long as the shell.

Dimensions. — Length of the three joints a O'OIS, b 0'05, c 01 ; breadth, a 0-02, b O'OY, c 0'07.

Habitat. — Fossil in Barbados.

5. Theopera chytropus, n. sp. (PL 67, fig. 6).

*

Shell slender, ovate, with distinct collar, but indistinct lumbar stricture. Length of the three
joints = 1:2:5, breadth =1:3:3. Cephalis hemispherical, with a conical horn of the same
length. Pores in the thorax and abdomen of similar shape, irregular, roundish. Three wings with
broad triangular base attached at the upper half of the shell, in the lower half free, diverging, with
a spinulate knob at the distal end.

Dimensions. — Length of the three joints, a 0'025, b 0'06, c 015 ; breadth, a 0'03, b OD9, c 0'09.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

6. Theopera cortina, n. sp. (PI. 67, fig. 8).

Shell slender, ovate, with distinct collar, but indistinct lumbar stricture. Length of the three
joints =1:2:6, breadth 1:4:4. Cephalis subspherical, with an elegant pyramidal horn of three
times the length, bearing an ovate, spinulate knob. Pores subregular, circular, two or three times
as large in the abdomen as in the thorax. The three wings are slightly elevated small ribs on the
thorax, arise with broad, triangular, striated bases in the upper half of the abdomen, and are pro-
longed into three slender diverging feet, which are as long as the shell, and bear a spinulate, ovate
knob at the distal end.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 013 ; breadth, a Q-Q3, b 0'08, c 0'08.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

REPORT ON THE RADIOLARIA. 1359

Genus 598. Rhopalocanium,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 54.

Definition. — T heoperida (vel Tricyrtida triradiata clausa) with three lateral
wings on the sides of the inversely conical abdomen, which bears no vertical terminal
horn on the basal apex.

The genus Rhopalocanium, and the closely allied Rhopalatractus which follows,
differ from the preceding Theopera, their probable ancestral form, in the origin of the
three lateral wings from the inversely conical abdomen, the thorax bearing no wings.
The upper part of the wing bases, which arose formerly from the thorax, is here reduced
and lost.

1. Rhopalocanium lasanum, n. sp. (PI. 67, fig. 10).

Shell subovate, with two distinct strictures. Length of the three joints =1:2:3, breadth =
1:3:4. Cephalis hemispherical, with a conical, dimpled horn of twice the length. Thorax sub-
conical, abdomen campanulate, both with irregular, circular pores. Three wings cylindrical, divergent,
about as long as the shell, striated, with an ovate, dimpled knob at the distal end, their broad
triangular base being attached to the upper half of the abdomen. (Form rather variable.)

Dimensions. — Length of the three joints, a O02, b 0'07, c 0'09 ; breadth, a 0'03, b 0'09, c 012.

Habitat. — Central Pacific, Stations 263 to 268, depth 2650 to 3000 fathoms.

2. Rhopalocanium ornatum, Ehrenberg.

Rliopalor.anium ornatum, Ehrenberg, 1854, Mikrogeol.,Taf. xxxvi. fig. 9; Abhandl. d. k. Akad. d.
Wiss. Berlin, 1875, p. 82, Taf. xvii. fig. 8.

Shell nearly spindle-shaped, with two distinct strictures. Length of the three joints = 1:3:6,
breadth = 1:4:3. Cephalis hemispherical, with a stout, cylindrical horn of twice the length,
bearing a dimpled cone. Thorax ovate, campanulate. Abdomen inversely conical. Pores sub-
regular, circular, twice as large in the thorax as in the abdomen. Three wings compressed, slender,
divergent, slightly longer than the abdomen, bearing an ovate, dimpled cone at their distal end,
with the broad, triangular, striated base attached to the upper third of the abdomen.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c'0'12 ; breadth, a 0'025, b 0'08, c 0'07.

Habitat. — Fossil in Barbados.

3. Rhopalocanium cortinium, n. sp.

Shell slender, ovate, nearly of the same form as, and with similar fenestration to that of Theo-
pera mrtina, (PI. 67, fig. 8). It differs from the latter mainly by the absence of the three thoracic
ribs, characteristic of Theopera. Length of the three joints =1:2:6, breadth =1:4:4. The

1 Rhopalocanium = Basket with clubs ; g&roXw, xanfon.

1360 THE VOYAGE OF H.M.S. CHALLENGER.

three wings arise by a broad, triangular, striated base from the upper half of the abdomen, below
the lumbar stricture. The cephalic horn and the three divergent wings are shorter, and at the
distal end not so much thickened as in Theopera cortina.

Dimensions. — Length of the three joints, a 0'025, 1 0'045, c 012 ; breadth, a 0'03, b 0'07, c 008.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

4. Rhopalocanium pythia, n. sp.

Rhopalocanium ornaturn, Bury, 1862, Polycystins of Barbados, pi. vi. fig. 1.

Shell nearly ovate, with two deep strictures. Length of the three joints = 1:4:8, breadth =
1:4:4. Cephalis subspherical, with a conical horn of three times the length. Thorax inflated,
abdomen inversely campanulate and prolonged into a short, conical, latticed tube. Pores sub-
regular, circular. Three wings slender, as long as the abdomen, arising by a broader base from the
uppermost part of the abdomen, their thickened end being curved inwards.

Dimensions. — Length of the three joints, a 0'02, b 0'07, c 015 ; breadth, a 0'03, b 0'08, c 0'07.

Habitat. — Fossil in Barbados.

5. Rhopalocanium delphicum, n. sp. (PL 67, fig. 9).

Shell nearly spindle-shaped, with two deep strictures. Length of the three joints = 1:2:4,
breadth =1:3:3. Cephalis hemispherical, with a slender, conical, curved horn, as long as the
hemispherical thorax. Abdomen inversely campanulate, prolonged into a short, conical, latticed tube.
Pores subregular, circular. Three wings arising by a narrow base from the uppermost part of the
abdomen, slender, cylindrical, S-shaped, curved, divergent, with a thick scaly appendix like a fir-
cone at the distal end.

Dimensions. — Length of the three joints, a 0'025, b 0'07, c 014 ; breadth, a 0'03, b 0"09, c O'OS.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 599. Rhopalatractus,1 Haeckel, 1881, Prodromus, p. 437.

Definition. — T heoperida (vel Tricyrtida triradiata clausa) with three lateral
wings on the sides of the inversely conical abdomen, which bears a vertical terminal
horn on the basal apex.

The genus Rhopalatractus, one of the most remarkable forms of Tricyrtida, differs
from the preceding Rhopalocanium, its ancestral form, in the production of a vertical,
basal horn, which descends from the basal apex of the inversely conical abdomen, and
is opposed to the upper apical horn of the cephalis. The shell becomes here, therefore,
exquisitely spindle-shaped.

1 Rliopalatractut = Spindle with clubs ;

REPORT ON THE RADIOLARIA. 1361

1. Rhopalatractus pentacanthus, n. sp. (PI. 68, fig. 11).

Shell very thick-walled, with two sharp strictures. Length of the three joints = 1:6:8,
breadth = 1:6:7. Cephalis hemispherical, with conical cavity, and a conical horn of twice the
length. Thorax subspherical, separated from the abdomen by a deep lumbar stricture, with small,
regular, circular, hexagonally-framed pores. Abdomen three-sided prismatic, with three strong,
prominent, wing-shaped edges, which are slightly divergent towards the base, and prolonged into
three pyramidal feet about as long as the thorax. Pores of the abdomen disposed in longitudinal
rows, which are separated by denticulate crests. Abdominal base inversely pyramidal, and prolonged
into a very large, cylindrical, basal, axial spine, nearly as long as the whole shell.

Dimensions. — Length of the three joints, a 0'02, b 012, c 015 ; breadth, a 0'03, b Oil, c 014.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Rhopalatractus foveolatus, n. sp. (PI. 68, fig. 10).

Shell slenderly ovate, thick-walled, with rough, dimpled surface. Length of the three joints =
1:3:5, breadth = 2:4:4. Cephalis hemispherical, with spherical cavity, and a thick, conical
spine of the same length. Thorax subspherical, with subregular, circular pores. Abdomen
inversely conical, with larger, irregular, roundish pores, prolonged at the distal end into a
cylindrical, axial, basal spine of about half its length. From the middle part of the abdomen arise
three lateral, conical feet, which are slightly curved and divergent downwardly, scarcely as long
as the basal spine. All five spines are dimpled.

Dimensions. — Length of the three joints, a 0'02, I 0'06, c 01 ; breadth a 0'04, b 0'08, c 0'08.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Rhopalatractus fusiformis, n. sp.

Shell slender, spindle-shaped, nearly of the same form as in the preceding species. Length of
the three joints = 1:2:6, breadth = 1:2:2. Cephalis subspherical, with a cylindrical horn three
times the length. Pores subregular, circular, of equal breadth in the thorax and in the abdomen,
which is prolonged into a cylindrical, axial, basal spine of the same length. From the upper third
of the abdomen arise, from a broad triangular base, three conical wings of half the length, divergent
and slightly curved inwards.

Dimensions. — Length of the three joints, a 0'025, b O'Oo, c 015 ; breadth, a 0'03, b 0'06, c 0'06.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

4. Rhopalatractus fenestratus, n. sp. (PL 68, fig. 12).

Dictyatractus fenestratus, Haeckel, 1881, Prodromus et Atlas.

Shell nearly spindle-shaped, with two distinct strictures. Lengtli of the three joints =1:3:6,
breadth = 1:4:4. Cephalis hemispherical, with a large, club-shaped horn, nearly as long as , the
abdomen, sulcated by longitudinal ribs, which are elegantly denticulate in the distal half. Thorax

(ZOOL. CHALL. BXP. — PART XL. 1886.) Rr 171

1362 THE VOYAGE OF H.M.S. CHALLENGER.

subspherical. Abdomen subovate, prolonged into a pyramidal, axial, basal spine, half as long as the
thorax. Pores subregular, circular. From the upper half of the abdomen arise three stout, lateral,
divergent wings of about the same length, which are curved inwards and fenestrated both at the
broad triangular base and at the thickened, three-edged distal end.

Dimensions. — Length of the three joints, a O02, b 0'06, c 012 ; breadth, a 0'03, b 0'08, c 0'08.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 600. Lithochytris,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 54.

Definition. — T heoperida (vel Tricyrtida triradiata clausa) with a three-sided
pyramidal abdomen, the triangular base of which is prolonged at the three corners into
three terminal feet.

The genus Lithochytris differs from all the other Theoperida in the absence of
lateral wings and the possession of three divergent, terminal feet, which arise from the
three corners of the three-sided pyramidal abdomen. It repeats, therefore, among the
Tricyrtida, that characteristic formation which Sethochytris and Tetrahedrina represent
among the Dicyrtida. Some species may be derived from Pterocanium, other species
from Podocyrtis, by the development of a lattice-plate closing the terminal mouth.

Subgenus 1. Lithochytrodes, Haeckel.

Three feet of the abdomen solid, not fenestrated, representing external apophyses
of the triangular shell-base.

1. Lithochytris cortina, n. sp. (PI. 67, fig. 12).

Shell three-sided pyramidal, without external strictures, but with two internal girdles. Length
of the three joints = 2 : 2 : 5, breadth = 3 : 4 : 6. Cephalis large, truncate-pyramidal, with nine deep
divergent ribs (and nine longitudinal rows of pores between them), and with a stout pyramidal horn
of half the length. The three prominent edges of the thorax and abdomen are prolonged over the
base of the pyramid into three very stout, solid, subovate feet, about as long as the thorax.

Dimensions. — Length of the three joints, a 0'04, b 0'04, c 01 ; breadth, a 0-06, b 0'08, c 012.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Lithochytris pyriformis, n. sp. (PL 67, fig. 13).

Shell pyramidal, nearly pear-shaped, with two distinct strictures. Length of the three joints =
1:1:3, breadth =1:2:3. Cephalis large, pear-shaped, with a short pyramidal .horn of half the

-1 Lithochytris =Pot of silex;

REPORT ON THE RADIOLARTA. 1363

length. Thorax and abdomen rounded, without prominent edges. Three basal feet pyramidal, solid,
nearly vertical, as long as the thorax. Pores irregular, roundish, in the abdomen large, twice to three
times as broad as in the thorax.

Dimensions. — Length of the three joints, a 0'03, b O03, c 0'08 ; breadth, a 0-04, b 0'06, c 0'09.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

3. Lithochytris tripodium, Ehrenberg.

Lithochytris tripodium, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iv.
fig. 11.

Shell pyramidal, nearly pear-shaped, with two distinct strictures. Length of the three joints =
1:2:4, breadth = 1:2:5. Cephalis with a horn of the same length, conical. Thorax and abdomen
rounded, without prominent edges. Three basal feet conical, solid, strongly divergent, shorter than
the thorax. Pores subregular, circular, twice as broad in the abdomen as in the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0-03, b 0'05, c 01.

Habitat. — Fossil in Barbados.

Subgenus 2. Lithochytridium, Haeckel.

Definition. — Three feet of the abdomen hollow and fenestrated, representing direct
protuberances or corner prolongations of the triangular shell-base.

4. Lithochytris galeata, n. sp. (PI. 67, fig. 16).

Shell pyramidal, with two sharp strictures. Length of the three joints = 1:1:4, breadth =
1:2:4. Cephalis subspherical, with an oblique pyramidal horn of the same length. Thorax some-
what larger. Abdomen inflated, with three sharp, prominent edges, which are prolonged over the
shell-base into three pyramidal, hollow, and fenestrated feet, longer than the thorax. Pores
subregular, circular, twice as broad in the abdomen as in the thorax.

Dimensions. — Length of the three joints, a 0'025, b 0'025, c 01 ; breadth, a 0'025, b 0'05, c 01.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

5. Lithochytris pileata, Ehrenberg.

Lithochytris pileata, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 76, Taf. v.
fig. 3.

Shell three-sided pyramidal, with deep collar, but indistinct lumbar stricture. Length of the
three joints = 2 : 2 : 9, breadth = 3 : 5 : 10. Cephalis with a conical horn of the same length, pear-
shaped. Thorax very short and broad. Abdomen inflated, with three sharp, prominent edges, which

1364 THE VOYAGE OF H.M.S. CHALLENGER.

are prolonged over the shell-base into three pyramidal, hollow and fenestrated feet, the lower edge
of which is horizontal. Pores regular, circular, of equal size in the thorax and abdomen.

Dimensions. — Length of the three joints, a 0'02, b 0'02, c 0'09 ; breadth, a 0'03, I 0'05, c 01.

Habitat. — Fossil in Barbados.

6. Lithochytris lucerna, n. sp. (PI. 67, fig. 14).

Shell three-sided pyramidal, with two indistinct strictures. Length of the three joints = 1:2:5,
breadth = 2:3:8. Cephalis small, with a horn of the same length, conical. Thorax with sub-
spherical cavity. Abdomen with three rounded, prominent edges, which are prolonged over the
shell-base into three conical, hollow, and fenestrated feet, twice as long as the thorax, with a thick,
pyramidal, terminal spine. Pores subregular, circular, of equal size in the thorax and abdomen.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 01 ; breadth, a 0'04, b 0'06, c 016.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

7. Lithochytris lanterna, n. sp. (PI. 67, fig. 11).

Shell three-sided pyramidal, with two distinct strictures. Length of the three joints = 1:2:4,
breadth = 1:3:6. Cephalis small, with a pyramidal slender horn of twice the length. Thorax
with subspherical cavity. Abdomen with three sharp prominent edges, which are prolonged over
the convex shell-base into three slender, prismatic, hollow, fenestrated feet, strongly divergent, twice
as long as the thorax (seen in fig. 11 from the vaulted base). Pores circular, twice as broad in the
abdomen as in the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'02, b 0'06, c 012.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

8. Lithochytris pyramidalis, Ehrenberg.

Lithochytris pyramidalis, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. v.
fig. 1.

Shell three-sided pyramidal, without external strictures, but with two internal transverse
girdles. Length of the three joints = 1:2:6, breadth = 2:4:8. Cephalis with a short horn of
half the length, conical. Cavity of the thorax subspherical. Abdomen with three rounded edges,
prolonged over the concave base into three pyramidal, hollow, and fenestrated feet, twice as long as
the thorax. Pores large, irregular, roundish.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 012 ; breadth, a 0'04, b 0'08, c 016.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms ; fossil in Barbados.

9. Lithochytris pteropus, n. sp. (PI. 67, fig. 15).

Shell three-sided pyramidal, with two indistinct strictures, but with two broad, internal girdles.
Length of the three joints = 2:2:6, breadth = 2:3:9. Cephalis with a small horn of half the

REPORT ON THE RADIOLARIA. 1365

length, pear-shaped. Thorax broader than long. Abdomen with three prominent, rounded edges,
prolonged over the concave base into three conical, hollow, and fenestrated feet, twice as long as the
thorax. Pores small, circular, irregular, in longitudinal series along the edges.

Dimensions. — Length of the three joints, a 0'04, b 0'04, c 012 ; breadth, a 0'04, b 0'06, c 018.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

10. Lithochytris vespertilio, Ehrenberg.

Litfiochytris vespertilio, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 76, Taf. iv.
fig. 10.

Shell three-sided pyramidal, with two indistinct strictures. Length of the three joints =1:2:5,
breadth = 2:3:10. Cephalis with a short horn of half the length, conical. Thorax inflated.
Abdomen without prominent edges, divided in the lower half into three large, conical, hollow, and
fenestrated feet, twice as long as the thorax. Pores small, irregular, roundish.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 01 ; breadth, a 0'04, b 0'06, c 0'2.

Habitat. — Fossil in Barbados.

Family LXVI. PHORMOCYRTIDA, n. fam.

Theophormida et Theoplicenida, Haeckel, 1881, Prodromus, pp. 436, 437.

Definition. — Tricyrtida multiradiata. (Cyrtoidea with a three-jointed
shell, divided by two transverse constrictions into cephalis, thorax, and abdomen, with
numerous, four to nine or more, radial apophyses.)

The family Phormocyrtida, composed of the Theophormida and Theophsenida
of my Prodromus, comprises those Cyrtoidea in which the lattice-shell is three-
jointed, and bears numerous radial appendages (usually six or nine, sometimes more,
rarely less, four or five). The two subfamilies differ in the shape of the terminal mouth,
which is in the Theophormida a simple wide opening, in the Theophsenida closed by a
lattice-plate. The phylogenetic origin of the Phormocyrtida may be found either in the
Podocyrtida or in the Anthocyrtida ; they may be derived either from the former by
interpolation of interradial, secondary apophyses between the three primary perradial
apophyses ; or from the latter by development of an abdomen.

The radial apophyses are originally radial ribs, which arise from the base of the
cephalis on the collar stricture, run along the thorax and abdomen, and are often pro-
longed into terminal feet. Whilst in some forms the radial ribs are completely
preserved in both joints, they are in other forms only partly visible (in the abdomen),
and very often only their free terminal prolongations are preserved in the form of a corona
of feet around the mouth of the thorax. This corona is either simple or double. Some-
times also a corona is developed on the lumbar stricture, between the thorax and abdomen.

1366

THE VOYAGE OF H.M.S. CHALLENGER.

These apophyses exhibit a remarkable variety in the great subfamily Theophormida, with
open mouth. In the small subfamily Theophsenida, however, the apophyses appear as
six or nine simple lateral wings on the abdomen.

The Theophormida are richly represented not only in the present seas, but also as
fossils in Barbados, and numerous remarkable forms have been already described by
Ehrenberg, in his genera Calocyclas and Cydadophora. Many Phormocyrtida belong
to the most elegant and admirable forms of Radiolaria.

I. Subfamily

Theophormida.
Terminal mouth of the
abdomen a simple
wide opening.

II. Subfamily

Theophsenida.

Synopsis of the Genera of Phormocyrtida.

'

Abdomen flat, dilated, with

Eadial ribs
enclosed in
the wall of

Eadial ribs in
the thorax and •<
the abdomen.

a wide open mouth,

Abdomen ovate or cylin-
drical, with constricted

the shell,

mouth, .

either the

thorax

f Peristome with free ter-

or the

Kadial ribs in rainal feet,

abdomen.

the abdomen -

only. Peristome smooth, without

[ free feet,

'

' Abdomen cylindrical or

No radial

Terminal

ovate, not dilated,

ribs in the

.

shell-wall.

corona simple.

Abdomen dilated, truncate,

Peristome

<

conical or discoidal,

with a

corona of

j

[Both coronas terminal,

terminal

Corona of feet

feet.

double.

One corona terminal, the

'

other lumbar,

Terminal mouth of the ab-
domen closed by a lattice-
plate.

Six lateral wings, .
Nine lateral wings, .

601. TheopJiormis.

602. Phormocyrtis.

603. Alacorys.

604. Cycladophora.

605. Calocydas.

606. Clathrocyclas.

607. Lamprocydas.

608. Diplocydas.

609. Hexalatractus.

610. Theqphama.

Subfamily 1. THEOPHORMIDA, Haeckel, 1881, Prodromus, p. 436.

Definition. — P hormocyrtida with the basal mouth of the shell open (vel
Tricyrtida multiradiata aperta).

Genus 601. Theophormis,1 Haeckel, 1881, Prodromus, p. 436.

Definition. — T heophormida (vel Tricyrtida multiradiata aperta) with numerous
radial ribs enclosed in the wall of the thorax and of the flat dilated abdomen ; mouth
of the latter wide open.

1 Theophormis - Divine basket ; feo;,

REPORT ON THE RADIOLARIA. 1367

The genus Theophormis commences the series of the Theophormida, or the multi-
radiate Podocyrtida, as their oldest and simplest form. The three-jointed shell is flat,
campanulate or hat-shaped, and pierced by four or more radial ribs, four of which are
primary or perradial, the others secondary or interradial. Theophormis may be derived
from the similar Sethophormis by development of a lumbar constriction, and a third
joint or abdomen.

1. Theophormis callipilium, n. sp. (PI. 70, figs. 1—3).

Shell flat, hat-shaped, with two sharp annular strictures. Cephalis large, flatly cap-shaped, with
small, irregular, square meshes (fig. 3). The collar septum (fig. 2) is composed (as in the following
species) of four crossed, thin, horizontal beams, each of which is inserted at the collar stricture by
a three forked branch. From the centre of the collar stricture (in the common nodal point of the
four beams) there arises a vertical, axial rod, which is inserted at the flat top of the cephalis by five
branches (one central and four lateral). Length of the three joints = 1:3:2, breadth = 2:6:11.
Thorax flat, campanulate, with four primary perradial ribs (prolongations of the four cortinar beams),
and numerous (twenty to thirty) interpolated secondary ribs ; four of these are interradial (mid-
way between the four primary ribs), and bisect the four large, semicircular, perradial meshes at the
base of the thorax. Network of the thorax and abdomen subregular, with hexagonal meshes and
thin bars. Abdomen flatly expanded, somewhat curved, like the brim of a hat, half as broad in
the anterior (frontal) part as in the posterior (occipital) part, which is about as broad as the radius
of the thorax. The twenty to thirty radial ribs of the abdomen are prolongations of the thoracic
ribs, and are somewhat prominent at the margin of the peristome, which appears therefore elegantly
indented.

Dimensions. — Length of the three joints, a O02 to 0'03, b 0'06 to 008, c 0'03 to 0'06 ; breadth,
a 0-05 to 0-08, b O2 to 0'3, c 04 to 0'5.

Habitat. — Central Pacific, Station 271, surface.

2. Theophormis medusa, n. sp.

Shell flatly campanulate, with two distinct, annular strictures. Length of the three joints =
1:2:1, breadth = 2:5:8. Cephalis large, hemispherical. Thorax flatly conical, with four crossed
ribs, opposite in pairs in two meridional planes, perpendicular one to another, and prolonged into the
flat, nearly discoidal abdomen, which is half as broad as the thorax. The wall of the abdomen is
pierced by eight radial ribs ; four secondary ribs being interpolated between the four primary. Net-
work of the entire shell very delicate, with regular, hexagonal meshes, and very thin bars. Peristome
circular, not dentate.

Dimensions. — Length of the three joints, a 0'03, b 0'07, c 0'04 ; breadth, a 0'06, b 016, c 0'24.

Habitat. — Central Pacific, Station 266, surface.

3. Theophonnis cruciata, n. sp.

Shell flat, campanulate, with two distinct annular strictures. Cephalis flat, cap-shaped, with
irregular, square meshes. Thorax flat, conical, with hexagonal meshes. Abdomen flatly expanded,

1368 THE VOYAGE OF H.M.S. CHALLENGER.

of half the breadth, with larger hexagonal meshes. Thorax and abdomen pierced by four stout
radial ribs, lying opposite in pairs in two diameters, perpendicular one to another. No secondary or
interradial ribs are interpolated between the four primary. Mouth truncate, circular.

Dimensions. — Length of the three joints, a 0'02, 5 0'08, c 0'04 ; breadth, a 0'05, I 018, c 0'25.

Habitat. — Central Pacific, Station 274, surface.

4. Theophormis senaria, n. sp.

Shell flat, hat-shaped, similar to Theophormis callipilium (PI. 70, figs. 1-3), but with a different
number and arrangement of the piercing radial ribs. The cephalis and its collar septum exhibit the
same formation as in Sethophormis hexalactis, described above (p. 1245, PI. 56, fig. 6.) The caudal
and sternal ribs, which are opposed in the sagittal plane, are simple, whilst the two lateral ribs are
forked. In the flat abdomen there are six secondary or interradial ribs, interpolated between the six
primary or perradial ribs of the thorax. Delicate network with regular, hexagonal meshes.

Dimensions. — Length of the three joints, a 0'035, & 0'075, c O025 ; breadth, a 0'07, 0'2, c 0'3.

Habitat. — Central Pacific, Station 272, surface.

Genus 602. Phormocyrtis,1 n. gen.

Definition. — T heophormida (vel Tricyrtida multiradiata aperta) with numerous
radial ribs enclosed in the wall of the thorax, and of the ovate or cylindrical abdomen ;
mouth of the latter constricted.

The genus Phormocyrtis differs from the preceding Theophormis in the ovate or
cylindrical form of the abdomen, the mouth of which is more or less constricted. The
former exhibits, therefore, the same relation to the latter that Sethamphora bears to
Sethophormis among the Dicyrtida. Phormocyrtis may be derived directly either
from Sethamphora by development of an abdomen, or from Pterocorys or Theopilium
by multiplication of the three radial ribs.

1. Phormocyrtis carinata, n. sp.

Shell ovate, with two slight strictures. Length of the three joints = 1:2:3, breadth = 1:3:4.
Cephalis hemispherical, with a stout pyramidal horn of twice the length, and few very small
pores. Pores in the campanulate thorax and the inflated abdomen regular, circular, small, and
numerous. Six stout prominent ribs, beginning from the collar stricture, arise along the thorax
and abdomen, and reach the constricted mouth, which is half as broad as the abdomen. (This
species is very similar to Pterocorys carinata, from which it differs in the six complete radial ribs of
the shell-wall.)

Dimensions. — Length of the three joints, a 0'03, & 0'06, c 0'09 ; breadth, a 0'03, I 0'09, c 012.

Halitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

1 Phormocyrtis = Plaited basket;

REPORT ON THE RADIOLARIA. 1369

2. Phormocyrtis fastosa, Ilaeckel.

Eucyrtidium faslosum, Ehrenberg, 1872 Abhandl. d. k. Akad. d. "Wiss. Berlin, p. 291, Taf. ix.
fig. 19. "

Shell ovate, with two distinct strictures. Length of the three joints = 1:3:3, breadth = 1:5:6.
Cephalis ovate, with a stout pyramidal horn of the same length, and numerous rather large pores.
Pores in the campanulate thorax and the inflated abdomen much smaller, very numerous, regular,
hexagonal. Along these two joints arise nine delicate, divergent ribs ; these extend almost to the
wide mouth, which is slightly constricted.

Dimensions. — Length of the three joints, a 0'03, 1 O09, c 0'08 ; breadth, a 0'02, b 01, c 012.

Habitat. — Indian Ocean (Zanzibar), depth 2200 fathoms, Pullen.

3. Phormocyrtis costata, n. sp. (PI. 69, fig. 6).

Shell smooth, with sharp collar, but indistinct lumbar stricture. Length of the three joints =
2:5:5, breadth = 2:6:6. Cephalis conical, with a stout pyramidal horn of twice the length.
Thorax and abdomen together nearly cylindrical, constricted towards both poles, with thirty to forty
longitudinal ribs, which are nearly parallel, vertical in the middle part, and convergent towards both
poles ; alternate with the same number of longitudinal rows of regular, circular pores. Mouth with
a broad, hyaline, only slightly constricted peristoine.

Dimensions. — Length of the three joints, a 0'04, b 01, c 01 ; breadth, a 0'04, b 012, c 012.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Phormocyrtis embolum, Haeckel.

Eucyrtidium embolum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. x. fig. 5.

Shell smooth, with sharp collar, but indistinct lumbar stricture. Length of the three joints =
3 : 7 : 10, breadth = 3 : 9 : 7. Cephalis subspherical, with a pyramidal horn of the same length.
Thorax campanulate ; abdomen inversely truncate, conical ; both with sixteen to twenty longitudinal
ribs, and alternate longitudinal rows of small circular pores, converging towards the two poles.
Mouth truncate, with broad hyaline peristome.

Dimensions. — Length of the three joints, a 0-03, b 0'07, c 01 ; breadth, a 0'03, b 0'09, c 0'07.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms ; fossil in Barbados.

5. Phormocyrtis quadrata, n. sp.

Shell ovate, papillate, with two slight strictures. Length of the three joints = 2:3:13,
breadth = 4 : 6 : 11. Cephalis hemispherical, small, with two divergent, pyramidal horns of twice
the length. Along the hemispherical thorax and the ovate inflated abdomen run twenty-four to
thirty curved ribs, converging towards the two poles, and alternate with the same number of longi-

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rrl72

1370 THE VOYAGE OF H.M.S. CHALLENGER.

tudinal rows of circular, regular pores, disposed in ten to twelve transverse rows. Each pore with
a square, elevated frame. Mouth constricted, only one-third as broad as the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 013 ; breadth, a 0'04, b 0'06, c Oil.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

6. Phormocyrtis longicornis, n. sp. (PI. 69, fig. 15).

Theocorys longicornis, Hacckel, 1881, Prodromus et Atlas, loc. cit.

Shell slender, ovate, rough, with two slight strictures. Length of the three joints = 3:8:12,
breadth = 4 : 10 : 11. Cephalis hemispherical, with a very large, cylindrical horn, about as long
as the shell. Thorax hemispherical, with regular, circular, hexagonally-framed pores. Abdomen
subcylindrical, with twenty to twenty-four nearly parallel undulate ribs, and alternate longitudinal
rows of regular, circular pores. Mouth constricted, circular, about half as broad as the thorax.

Dimensions. — Length of the three joints, a 0'03, b 0'08, c 012 ; breadth, a 0'04, b 01, c Oil.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

Genus 603. Alacorys,1 Haeckel, 1881, Prodromus, p. 436.

Definition. — T heophormida (vel Tricyrtida multiradiata aperta) with numerous
radial ribs in the abdomen, which are prolonged over the mouth into free feet.

The genus Alacorys and the following Cydadophora differ from the preceding two
genera in the formation of the radial ribs, which arise from the lumbar stricture, and lie
in the wall of the abdomen, but are absent on the thorax. The shell is usually large,
more or less pyramidal or conical, with a wide open terminal mouth. The latter is in
Cydadophora simply truncate, whilst in Alacorys it is surrounded by from four to
twelve or more terminal feet, prolongations of the abdominal ribs. According to the
different number of these (four, five, six, or more) some subgenera may be distinguished,
as Tetralacorys, Pentalacorys, Hexalacorys, &c.

Subgenus 1. Tetralacorys, Haeckel, 1881, Prodromus, p. 436.

Definition. — Peristome armed with four feet, opposite in two meridian planes, which
are perpendicular to one another.

1. Alacorys lutheri, n. sp. (PL 65, fig. 4).

Shell papillate, with distinct collar stricture. Length of the three joints = 3:6:6, breadth =
3 : 8 : 10. Cephalis subpherical, with a pyramidal horn of the same length. Thorax tuberculate,

1 A lacorys = Wing-helmet.

REPORT ON THE EADIOLAR1A. 1371

nearly hemispherical, with circular pores of very different sizes. From the margin of its wide open
mouth descend four stout perradial ribs, which are forked at the distal end, and by communication
of their fork-branches form, the four large, pentagonal holes of the abdomen. From the middle of
the lower margin of the holes descend four parallel, vertical, slender feet, about as long as the shell.
This species is dedicated to the memory of the great Reformer, Martin Luther.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c O06 ; breadth, a 0'03, b 0'08, c 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Alacorys tetracantha, Haeckel.

Podoeyrtis tetracantha, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xiii.

fig. 2.

1 Podoeyrtis parvipes, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xiv.
fig. 5.

Shell rough, with distinct collar stricture. Length of the three joints =1:3:5, breadth =
1:4:6. Cephalis subspherical, with a rudimentary conical horn. Thorax campanulate, with irregular,
roundish pores of different sizes. Abdomen inflated, with a small number of very large irregular
holes, intermingled with smaller roundish holes. From the margin of the wide open mouth descend,
nearly vertically, four strong vertical feet, which are about as long as the shell, and slightly curved,
with convex outlines. Podoeyrtis parvipes of Ehrenberg seems to be only a mutilated specimen of
this species.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c O09 ; breadth, a 0'03, b 0'08, c 013.

Habitat. — Fossil in Barbados.

Subgenus 2. Pentalacorys, Haeckel, 1881, Prodromus, p. 436.

Definition. — Peristome armed with five feet, one of which is odd and occipital,
the other four paired and lateral.

3. Alacorys pentacantha, Haeckel.

fodocyrtis pentacantha, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82, Taf. xvii.
fig. 1.

Shell rough, with slight collar stricture. Length of the three joints = 1:2:3, breadth =
1:4:6. Cephalis subspherical, with a rudimentary conical horn. Thorax campanulate, with
subregular, circular, quincuncial pores. Abdomen wider, campanulate, with a small number of very
large and irregular, roundish holes. From the peristome descend five stout conical feet, which are
slightly curved and divergent, nearly as long as the shell.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'06 ; breadth, a 0'025, b 0'08, c Oil.

Habitat. — Fossil in Barbados.

1372 THE VOYAGE OF H.M.S. CHALLENGER.

4. Alacorys bismarckii, n. sp. (PI. 65, fig. 3).

Shell spiny, with distinct collar stricture. Length of the three joints =1:4:5, breadth =
2 : 7 : 10. Cephalis hemispherical, with a very stout, dimpled, conical horn of the same length.
Thorax campanulate, spiny, with regular, circular pores. Abdomen wider, campanulate, with larger
conical spines, and a small number of irregular, roundish, very large holes. From the peristome
descend, nearly vertically, five very large cylindrical feet, nearly twice as long as the shell ; they are
S-shaped, curved, spinulate in the distal half, and armed at the proximal base with two stout
conical spines, the smaller of which is directed inwards, the larger curved upwards. Dedicated to
Prince Otto von Bismarck, the Reconstructor of the German Empire.

Dimensions — Length of the three joints, a 0'02, b 0'08, c 01; breadth, a 0'04, b 014, c 0'2.

Habitat. — Western Tropical Pacific (north of New Guinea), Station 220, depth 1100 fathoms.

Subgenus 3. Hexalacorys, Haeckel, 1881, Prodromus, p. 436.

Definition. — Peristome armed with six feet, three of which are primary or perradial
(Podocyrtis), the three other alternate, secondary or interradial.

5. Alacorys friderici, n. sp. (PI. 65, fig. 1).

Shell conical, rough, with sharp collar stricture. Cephalis subspherical, with a large, oblique,
prismatic horn, twice the length. Thorax campanulate, with regular, circular pores (six to
eight in its length). Abdomen wider, campanulate, with a small number of very large pores (three
to four in the course of its length). Peristome with six very large divergent feet, which are about
as long as the shell, cylindrical, irregularly curved. The specimen figured was observed living,
with expanded pseudopodia. The central capsule exhibited four large pear-shaped lobes, filling
up the shell-cavity ; each contained an oil-globule in the thoracic part. The undivided cephalic
part of the capsule enclosed a nucleus, from which four lobes protruded through the four collar
pores into the thorax. Dedicated to Frederick the Great, the Royal Philosopher of Potsdam.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 0'08 ; breadth, a 0'04, b 0'09, c 014.

Habitat. — North Atlantic, Canary Islands, Lanzerote (Haeckel), surface.

6. Alacorys guilelmi, n. sp. (PL 65, fig. 2).

Shell thorny, with distinct collar stricture. Length of the three joints = 1 : 3:4, breadth =
2:5:8. Cephalis hemispherical, with a rudimentary conical horn. Thorax hemispherical, spiny,
with regular, circular pores. Abdomen wider, campanulate, papillate, with a small number of
very large circular holes. Peristome with six diverging feet, which are about as long as the shell,
at the base conical, thickened, and at the distal end curved inwards, with a spinulate knob. Dedi-
cated to the German Emperor, Wilhelm.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'08 ; breadth, a 0'03, b 01, c 016.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

REPORT ON THE RADIOLARIA. 1373

7. Alacorys hexacantha, n. sp.

Shell thorny, with slight collar stricture. Length of the three joints = 2:5:7, breadth =
4:10: 14. Cephalis flat, cap-shaped, with a rudimentary conical horn. Thorax campanulate,
with regular, circular pores. Abdomen wider, campanulate, with a small number of very large
polygonal pores. Peristome with six large divergent feet, which are longer than the shell, cylin-
drical, and slightly curved, in the proximal half convex, in the distal half concave.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'07 ; breadth, a 0'04, b 01. c 0'14.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

8. Alacorys hexapleura, n. sp.

Shell spiny, with distinct collar stricture. Length of the three joints =2 : 10 : 8, breadth =
3 : 11 : 10. Cephalis hemispherical, large, hyaline, and thick- walled, with a very stout, conical horn
of the same length. Thorax pear-shaped, with numerous, regular, circular pores and conical spines,
the size of which increases gradually towards the deep, lumbar stricture. Abdomen truncate,
conical, with irregular, roundish pores, and six very strong, straight, divergent ribs, prolonged into
six short, conical feet.

Dimensions.— Length of the three joints, a 0'04, 6 0'2, c 016 ; breadth, a 0'06, 6 0'22, c 0'2.

Habitat. — Fossil in Barbados.

Subgenus 4. Octalacorys, Haeckel.

Definition. — Peristome armed with eight feet, four of which are primary or
perradial (corresponding to those of Tetralacorys), the other four alternate, secondary,
or interradial.

9. Alacorys aculeata, Haeckel.

Podocyrtis aculeata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 80,

Taf. xiii. fig. 3.
Podocyrtis aculeata, Biitschli, 1882, Zeitsehr. f. wiss. Zool., vol. xxxvi. p. 540, Taf. xxxiii. fig. 34.

Shell spiny, with deep collar stricture. Length of the three joints = 2:5:8, breadth = 2:7:10.
Cephalis subspherical, with a slender, conical horn of twice the length. Thorax campanulate,
thorny, with regular, circular pores. Abdomen wider, campanulate, with a small number of very
large, regular, hexagonal meshes, and stout spines in the nodal points. Peristome with eight strong
conical feet, which are nearly parallel, little curved (convex at the outside), and sometimes all of
the same size (equal to the length of the shell) ; at other times different, four larger alternating with
four smaller feet.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'08 ; breadth, a 0'025, b 0'07, c 01.

Habitat. — Fossil in Barbados.

1374 THE VOYAGE OF H.M.S. CHALLENGER.

10. Alacorys octacantha, n. sp.

Shell spiny, with deep collar stricture. Length of the three joints = 2:8:6, breadth = 3:7:7.
Cephalis ovate, with a short, conical horn. Thorax pear-shaped, spiny, with regular, circular pores,
similar to Cydadophora erinaceus, Ehrenberg (1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68,
Taf. xviii. fig. 2). Abdomen truncate, conical, with irregular, roundish pores, and eight stout,
straight, thorny, divergent ribs of equal size, which are prolonged into eight free, conical, spiny
feet of the same length.

Dimensions. — Length of the three joints, a 0'04, b 016, c 012 ; breadth, a 0'06, b 014, c 014.

Habitat, — Central Pacific, Station 265, depth 2900 fathoms.

Subgenus 5. Ennealacorys, Haeckel.

Definition. — Peristome armed with nine feet, three of which are primary or
perradial, the other six secondary or interradial.

11. Alacorys enneacantha, n. sp.

Shell papillate, with slight collar stricture. Length of the three joints = 2:4:8, breadth =
3:6:9. - Cephalis hemispherical, with a stout, conical horn of twice the length. Thorax cam-
panulate, with subregular, circular pores, and small, conical papillae. Thorax wider, campanulate,
with circular pores, and conical papillae of three times the size. Peristome with nine widely
divergent, little curved, conical feet, about as long as the shell. Similar to Podocyrtis vcntricosa,
Ehrenberg (1875, loc. cit., Taf. xvi. fig. 3), different mainly in the feet.

Dimensions. — Length of the three joints, a 0'02, I 0'04, c O'OS ; breadth, a 0'03, 5 0'06, c 0'09.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

12. Alacorys gigas, n. sp.

Shell thorny, with distinct collar stricture. Length of the three joints = 1:4:2, breadth =
1:5:4. Cephalis ovate, with a short, conical horn of about half the length. Thorax campanulate,
thorny, with small, regular, circular pores, very similar to Cydadoplwra gigas, Ehrenberg (loc. cit.,
1875, p. 68, Taf. xviii. fig. 1). Abdomen truncate, conical, smooth, with irregular, roundish pores,
and nine stout and straight, little divergent ribs, which are prolonged into nine cylindrical, pointed
feet of the same length.

Dimensions. — Length of the three joints, a O'Oo, b 0'2, c 01 ; breadth, a 0'05, b 0'25, c 0'2.

Habitat. — Fossil in Barbados.

Subgenus 6. Polyalacorys, Haeckel.

Definition. — Peristome with numerous (ten to twenty or more) prominent feet,
three or four of which are primary and perradial, the others secondary and iuterradial.

REPORT ON THE RADIOLARIA. 1375

13. Alacorys dodecantha, n. sp.

IPodocyrtis scJwmburgldi, var., Bury, 1862, Polycystins of Barbados, Taf. xii. fig. 3.

Shell smooth, with slight collar stricture. Length of the three joints = 1:3:4, breadth =
1:4:7. Cephalis ovate, with a conical horn of the same length. Thorax campanulate, with
regular, circular pores. From its margin arise twelve stout, little curved, radial beams, which are
widely divergent, and connected in the middle part by a transverse circular ring, so that the
abdomen exhibits twelve large triangular holes, and at the peristome, alternating with these, twelve
free conical feet of the same length.

Dimensions. — Length of the three joints, a 0'04, b 0'09, c Oil ; breadth, a 0'03, b 012, c 0'22.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms ; also fossil in Barbados.

14. Alacorys car cinus, n. sp. (PI. 74, fig. 9).

Calocydas carcimts, Haeckel, 1879, Atlas, loc. dt.

Podocyrtis schomburgkii, var., Bury, 1862, Polycystins of Barbados, pi. i. fig. 2 ; pi. xii. fig. 4.

Shell rough, with distinct collar stricture. Length of the three joints = 1:4:4, breadth =
2:6:6. Cephalis hemispherical, with a large, cylindrical, bent spine of three times the length.
Thorax inflated, campanulate, with large, regular, circular pores. Abdomen truncate, conical, with
three to four transverse rows of regular, square pores, produced by eighteen divergent, straight ribs,
which are connected by three to four horizontal rings. Distal end of the ribs prolonged into
eighteen slender, conical feet, which are about as long as the thorax and slightly curved inwards.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'08 ; breadth, a 0'05, b 012, c 012.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms ; also fossil in
Barbados.

15. Alacorys polyacantha, n. sp.

Shell spiny, with deep collar stricture. Length of the three joints = 3 : 9 : 10, breadth =
4 : 12 : 16. Cephalis hemispherical, with a stout conical horn of the same length. Thorax
campanulate, with regular, circular pores and conical spines, increasing in size towards the deep
lumbar stricture. Abdomen truncate, conical, with twenty to thirty divergent, straight ribs, which
are connected by four to six transverse rings, and prolonged into free conical feet of half the
length. Therefore four to six transverse rings of regular, square pores occur.

Dimensions. — Length of the three joints, a 0'03, b OD9, c 01 ; breadth, a 0'04, b 012, c 016.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

16. Alacorys ornata, Haeckel.

Cryptoprora ornata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. v. fig. 8.

Shell ovate, smooth, without external strictures, but with two internal annular septa. Length
of the three joints = 3:5:4, breadth = 3:6:5. Cephalis subspherical, partly enclosed by the
uppermost part of the thorax, without horn, or with a small rudimentary horn. Pores subregular,

1376 THE VOYAGE OF H.M.S. CHALLENGER.

circular, half as broad in the cephalis as in the two other joints. Thorax cauipanulate. Abdomen
truncate, with eighteen to twenty-four parallel, vertical, longitudinal ribs, which are prolonged into
slender, free, conical feet of the same length. (This remarkable species may be derived from
Carpocanium by apposition of a third joint.)

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'04 ; breadth, a 0'03, b 006, c 0'05.

Habitat. — Fossil in Barbados.

Genus 604. Cycladophora,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 54.

Definition. — T heophormida (vel Tricyrtida multiradiata aperta) with four to
six or more radial ribs in the abdomen, the terminal mouth of which is truncate, with-
out feet.

The genus Cycladophora differs from the preceding Alacorys, its probable ancestral
genus, in the absence of free terminal feet, the radial ribs of the abdomen being con-
nected by transverse beams throughout their whole length. The number of the
regularly disposed ribs (four to six or more) may also here be used for the distinction of
different subgeuera.

Subgenus 1. Lampterium, Haeckel, 1881, Prodromus, p. 434.

Definition. — Abdomen with four radial ribs, opposite in pairs in two meridian
planes, perpendicular one to another.

1. Cycladophora gcetheana, n. sp. (PI. 65, fig. 5).

Shell shaped like a lantern, with two sharp strictures. Length of the three joints = 1:2:12,
breadth = 1:4:7. Cephalis hemispherical, with a slender pyramidal horn of three times the length.
Thorax twice as large, thorny, hemispherical, with regular, circular pores. Abdomen very long,
nearly four-sided prismatic, with four superior smaller, and four inferior larger holes ; the former
separated by four short, divergent, perradial, the latter by four long, parallel, vertical, interradial
bars. Mouth square, four-lobed. Dedicated to Wolfgang Goethe.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'24 ; breadth, a 0'03, b 0'07, c 01 to
014.

Habitat. — Central Pacific, Stations 265 to 269, depth 2550 to 2900 fathoms.

2. Cycladophora tetrapleura, n. sp.

Shell very similar to the preceding species, but differing in the following characters : Cephalis
conical, with a horn of the same length. Thorax campanulate. Four ribs of the abdomen not

1 Cycladophora = Bearing a female robe ; xt/xXa

REPORT ON THE RADIOLARIA. 1377

parallel and vertical, but more or less divergent. Length of the three joints = 1:2:8, breadth =
1:2:4. Whole shell slender, pyramidal. Mouth square, four-lobed.

Dimensions. — Length of the three joints, a 0'03, b O06, c 0'24 ; breadth, a O03, b 0'06, c 012.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

3. Cycladophora lanterna, n. sp.

Shell very similar to the two preceding species, but differing in the following characters.
Cephalis subspherical, with a thick, pyramidal horn of the same breadth, and three times the
length. Thorax hemispherical, with circular, hexagonally-framed pores. Abdomen ovate, with
four convex ribs, and twelve large holes, four superior smaller pentagonal, four intermediate very
large, ovate, and four inferior, small, triangular holes. Mouth little constricted, nearly circular.

Dimensions. — Length of the three joints, a 0'025, b 0'05, c 0'22 ; breadth, a 0'025, b 0'08, c Oil.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Subgenus 2, Lamptidium, Haeckel.

Definition. — Abdomen with six radial ribs (three primary or perradial, and three
alternate, secondary or interradial).

4. Cycladophora hexapleura, n. sp.

Lanterna chinensis, Bury, 1862, Polycystins of Barbados, pi. xiii. fig. 7.

Shell shaped like a lantern, with six sides and two sharp strictures. Length of the three
joints = 1:2:8, breadth = 1:2:4. Cephalis hemispherical, with a conical spine of the same
length. Thorax twice as large, hemispherical, with regular, circular pores. Abdomen nearly six-
sided prismatic, with six descending, little curved ribs, and eighteen large holes between them ; six
superior holes interradial, ovate, six intermediate holes very large, perradial, ovate, six inferior
holes triangular, interradial. Mouth six-lobed.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 016 ; breadth, a 0-03, b 0'06, c 01.

Habitat. — Fossil in Barbados.

5. Cycladophora pyramidalis, n. sp.

Podoeyrtis sp., Bury, 1862, Polycystins of Barbados, pi. xii. fig. 2.

Shell slender, pyramidal, with six sides and two slight strictures. Length of the three joints =
1:4: 12, breadth = 1:4:8. Cephalis subspherical, with a conical horn of twice the length.
Thorax conical, with regular, circular pores. Abdomen truncate, pyramidal, with six strong,
divergent, straight ribs, which are connected by five to six transverse, hexagonal rings ; therefore

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 173

1378 THE VOYAGE OF H.M.S. CHALLENGER.

six longitudinal rows of large, roundish, quadrangular meshes (four to five meshes in each row).
Mouth hexagonal.

Dimensions. — Length of the three joints, a 0'025, b 01, c 0'3 ; breadth, a 0'03, b 01, c 0'2.

Habitat. — Fossil in Barbados.

6. Cycladophora spinosa, n. sp.

Shell spiny, with two deep strictures. Length of the three joints = 1:4:3, breadth = 1:5:4.
Cephalis subspherical, with a stout conical horn of the same length. Thorax ovate, with regular,
circular pores, and numerous conical spines. Abdomen truncate, conical, with irregular, roundish
pores, and six strong, divergent ribs. Mouth circular.

Dimensions. — Length of the three joints, a 0'03, b 012, c 009 ; breadth, a 0'03, b 015, c 012.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; fossil in Barbados.

Subgenus 3. Lamptonium, Haeckel.

Definition. — Abdomen with nine radial ribs (three primary or perradial, and six
secondary or interradial).

7. Cycladophora enneapleura, n. sp.

Shell spiny, with two sharp strictures. Length of the three joints =1:5:3, breadth = 2:7:4.
Cephalis hemispherical, with a conical horn of twice the length. Thorax campanulate, with regular,
circular pores, and conical thorax. Abdomen cylindrical, with nine straight, parallel ribs, and
irregular, roundish pores. Mouth circular. (Similar to Clydadophora gigas, Ehrenberg, 1875,
loc. cit., Taf. xviii. fig. 1, but differing in the possession of nine abdominal ribs.)

Dimensions. — Length of the three joints, a 0'03, b 015, c 01 ; breadth, a 0'06, b 0'2, c 012.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

8. Cycladophora nonagona, n. sp.

Shell spiny, with two distinct strictures. Length of the three joints = 3 : 10 : 7, breadth =
2:9:8. Cephalis pear-shaped, with a stout pyramidal horn of the same length. Thorax pear-
shaped, with regular, circular pores, and conical horns, increasing in size towards the base.
Abdomen truncate, pyramidal, with nine straight, spinulate ribs, and nine even faces between
them, with irregular, roundish pores. Mouth nonagonal.

Dimensions. — Length of the three joints, a 0'06, b 0'2, c 014 ; breadth, a 0'05, b 018, c 016.

Habitat. — Fossil in Barbados.

REPOET ON THE RADIOLARIA. 1379

Subgenus 4. Cyclampterium, Haeckel.

Definition. — Abdomen truncate, conical or campanulate, with numerous (ten to
twenty or more) divergent ribs. Mouth wide open, truncate.

9. Cycladophora pantheon, n. sp. (PI. 68, fig. 3).

Shell dome-shaped, with slight collar and deep lumbar stricture. Length of the three joints =
1:6:5, breadth = 1:7:8. Cephalis small, with a conical horn of the same length. Thorax
cupola-shaped, with large, regular, circular pores, and numerous pyramidal tubercles. Abdomen
with twelve (sometimes eleven or thirteen) slender, divergent ribs, which are connected at equal
distances by four to six horizontal rings, and so produce twelve longitudinal rows of large, regular,
square meshes.

Dimensions. — Length of the three joints, a 0'02, b 012, c 01 ; breadth, a 0'03, b 014, c 015.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

10. Cycladophora dodecapleura, n. sp.

Shell cupola-shaped, with two deep strictures. Length of the three joints = 2 : 5:6, breadth =
2:7: 10. Cephalis hemispherical, with a conical horn of twice the length. Thorax subspherical,
truncate at both poles, thorny, with regular, circular pores. Abdomen in the upper half with
a coronal of twelve large ovate holes, separated by twelve divergent, slender ribs, in the lower
half with curved, convergent prolongations of the twelve ribs, and numerous small, irregular,
roundish pores.

Dimensions. — Length of the three joints, a O'OIS, b 0'05, c 0'06 ; breadth, a 0'02, b 0'07, c 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

11. Cycladophora campanula, n. sp.

Shell campanulate, with two slight strictures. Length of the three joints =2:4:5, breadth
= 2 : 6 : 10. Cephalis ovate, with a conical horn of the same length. Thorax campanulate, rough,
with regular, circular pores. Abdomen dilated, with fifteen to twenty slender, divergent, little
curved ribs, which are connected by two or three horizontal rings, and from two or three trans-
verse rows of large, roundish, square pores.

Dimensions. — Length of the three joints, a 0'04, b 0'08, c 01 ; breadth, a 0'04, b 012, c 0'2.

Habitat. — North Atlantic, Bermuda, surface ; also fossil in Barbados.

12. Cycladophora spatiosa, Ehrenberg.

Cycladophora spatiosa, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. xviii.
figs. 5, 6.

Shell campanulate, with two slight strictures. Length of the three joints = 2:6:9, breadth =
3 : 8 : 14. Cephalis subspherical, with a conical horn of the same length. Thorax campanulate,

1380 THE VOYAGE OF H.M.S. CHALLENGER.

smooth, with regular, circular pores. Abdomen truncate, conical, with sixteen to twenty-four
divergent ribs, which are straight or slightly curved, and connected by from four to six transverse,
circular rings. The large regular meshes, so produced, form sixteen to twenty-four longitudinal
series, and are rounded in the upper, square in the lower transverse rows.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'09; breadth, a 0'03, b 0'08, c 014.

Habitat. — Fossil in Barbados.

13. Cycladophora favosa, n. sp. (PL 62, figs. 5, 6).

Shell dome-shaped, without collar stricture, but with a deep lumbar stricture. Cephalis flat,
cap-shaped, without horn, or with a rudimentary conical horn, with small circular pores. Length
of the three joints = 1:4:3, breadth = 2:5:4. Thorax subspherical, rough, with regular, circular,
hexagonally-framed pores. Abdomen truncate, conical, with eighteen to twenty-four prominent
ribs ; between every two ribs only two or three ovate pores occur. Mouth circular, with eighteen
to twenty -four teeth. The shape of the abdomen is rather variable (figs. 5, 6).

Dimensions. — Length of the three joints, a 0'02, b O08, c O06 ; breadth, a 0"04, b O09, c 0'07.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 5. Cyclamptidium, Haeckel.

Definition. — Abdomen nearly cylindrical or prismatic, with numerous (ten to
twenty or more) straight, vertical, parallel ribs. Mouth wide open, truncate.

14. Cycladophora fenestrata, n. sp. (PL 68, fig. 2).

Shell rough, with two slight strictures. Length of the three joints = 1:5:5, breadth = 1:6:5.
Cephalis conical, with a conical, dimpled horn of twice the length. Thorax nearly spherical, with
regular, circular pores, and small conical spines. Abdomen cylindrical, with eighteen stout,
parallel, vertical ribs, which are connected by six to eight horizontal, circular rings ; therefore
regular transverse and longitudinal rows of square or circular pores occur. Mouth truncate,
circular.

Dimensions. — Length of the three joints, a 0'02, b 01, c 01 ; breadth, a 0'03, b 012, c 01.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

15. Cycladophora stiligera, Ehrenberg.

Cycladophora stiligera, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. xviii.
fig. 3.

Shell smooth, with two distinct strictures. Length of the three joints = 2 : 7 : 8, breadth =
2:9:7. Cephalis subspherical, with a conical horn of twice the length. Thorax subspherical,
smooth, with regular, circular pores. Abdomen cylindrical, with twelve parallel, vertical ribs, which

REPORT ON THE RADIOLARIA. 1381

are connected by three to four broad, horizontal rings ; therefore subregular, transverse, and longi-
tudinal rows of roundish pores are present. Mouth truncate, circular.

Dimensions. — Length of the three joints, a 0'02, b O'OT, c 008 ; breadth, a 0'02, b 0'09, c 0'07.

Habitat. — Fossil in Barbados.

Genus 605. Calocyclas,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 54.

Definition. — T heophormida (vel Tricyrtida multiradiata aperta) with a simple
corona of terminal feet around the truncate mouth. Abdomen not dilated, cylindrical
or ovate. No ribs in the shell-wall.

The genus Calocyclas, and the three following closely allied genera, differ from the
four preceding genera of Theophormida in the absence of radial or longitudinal ribs
in the wall of the thorax and abdomen. These are completely reduced, and their
terminal prolongations only remain, forming a simple or double corona around the
mouth of the abdomen. They correspond therefore to Carpocanium and Anthocyrtis
among' the Dicyrtida. In Calocyclas the corona is simple. The mouth is not dilated,
but often constricted, and the abdomen is cylindrical or ovate, not conical. The teeth
of the corona are usually vertical or convergent.

Subgenus 1. Calocycletta, Haeckel.
Definition. — Thorax and abdomen smooth, without spines or thorns.

1. Calocyclas veneris, n. sp. (PI. 74, fig. 5).

Shell smooth, with two distinct strictures. Length of the three joints = 1:2:2, breadth =
1:4:3. Cephalis ovate, with a large, triangular, prismatic horn of three times the length. Thorax
hemispherical ; abdomen cylindrical ; both with regular, circular pores of equal size. Mouth truncate,
with a corona of nine to twelve vertical, lamellar feet, which are as long as the abdomen,
rectangular, twice as broad as their distance apart, and truncate at the end.

Dimensions. — Length of the three joints, a 0'03 to 0'04, b 0'06 to 0'08, c 0'04 to 0'06 ; breadth,
a 0-03 to 0-04, b 0'09 to Oil, c 0'08 to 01.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, many stations ; surface, and in various depths.

2. Calocyclas virginis, n. sp. (PL 74, fig. 4).

Shell smooth, with distinct collar, but indistinct lumbar stricture. Length of the three joints =
1:2:1, breadth = 1:4:3. Cephalis ovate, with a slender, conical horn, little shorter than the

1 Calocyclas = Beautiful female robe ;

1382 THE VOYAGE OF H.M.S. CHALLENGEE.

shell. Thorax suhspherical. Abdomen nearly cylindrical, little contracted towards the peristome.
Pores regular, circular, twice as broad in the thorax as in the abdomen, where they are separated by
slight longitudinal ribs. Corona of the peristome composed of sixteen to twenty-four vertical,
lamellar feet, which are longer than the abdomen, rectangular, and truncate at the end.

Dimensions.— Length of the three joints, a 0'04, b 0'08, c 0'05 ; breadth, a 0'03, 6 Oil, c O09.

Habitat. — Central Pacific, Station 225, depth 4475 fathoms.

3. Calocyclas minervce, n. sp.

Shell smooth, with two deep strictures, similar to Cycladophora stiligera. Length of the three
joints = 1:4:3, breadth = 1:4:3. Cephalis subspherical, with a large, conical horn of three times
the length. Thorax subspherical, with small, regular, circular pores. Abdomen cylindrical, with
truncate mouth and few irregular pores of different sizes, commonly arranged in three or four
subregular, transverse rows, with large intervening distances. Peristome with a corona of twelve
to twenty vertical, lamellar feet, which are about as long as the abdomen, and truncate at the end
(in Ehrenberg's figure these are broken off).

Dimensions. — Length of the three joints, a 002, b 0'08, c 0'06 ; breadth, a 0'02, b 0'09, c 0*07.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Calocyclas amicce, n. sp. (PI. 74, fig. 2).

Shell smooth, with two slight strictures. Length of the three joints = 2 : 4 : 5, breadth = 2:5:5.
Cephalis subspherical, with a pyramidal horn of the same length. Thorax campanulate-conical ;
abdomen nearly cylindrical ; both with small, subregular, circular pores. Peristome with a corona
of twelve to fifteen small, triangular feet, only as large as the thickness of the shell-wall, and
separated by distances of twice the size.

Dimensions.- — Length of the three joints, a 0'04, b 0'08, c 01 ; breadth, a 0'04, b 01, c 01.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

5. Calocyclas sacerdotis, n. sp.

Shell smooth, with two deep strictures. Length of the three joints = 1:3:4, breadth = 1 r 3 : 3.
Cephalis ovate, with a pyramidal horn of three times the length. Thorax campanulate, conical ;
abdomen twice the length, cylindrical ; both with small, regular, circular pores. Peristome somewhat
constricted, with a corona of nine to twelve conical feet, which are as long as the cephalis, and
with the ends curved inwards, protecting the mouth.

Dimensions. — Length of the three joints, a 0'03, b OD8, c 012 ; breadth, a 0'03, b 0'09, e 0'09.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

6. Calocyclas vestalis, n. sp. (PI. 74, fig. 3).

Shell smooth, with two deep strictures. Length of the three joints = 1:2:3, breadth = 1:3:3.
Cephalis subspherical, with a pyramidal horn of twice the length. Thorax campanulate ; abdomen

REPORT ON THE RADIOLARIA. 1383

nearly cylindrical ; both with regular, hexagonal pores, three times as broad as the bars. Peristome
constricted, half as broad as the abdomen, with a corona of nine conical, vertical feet as long as the
cephalis.

Dimensions. — Length of the three joints, a 0'03, b 0'07, c 01 ; breadth, a 0'035, b 01, c 01.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Subgenus 2. Calocyclissa, Haeckel.
Definition. — Thorax spiny or thorny ; abdomen smooth.

7. Calocyclas turris, Ehrenberg.

Calocyclas turris, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. xviii.
fig. 7.

Shell with two sharp strictures. Length of the three joints = 1:4:4, breadth =1:5:4
Cephalis hemispherical, with a stout conical horn of the same length. Thorax subspherical, thorny
with small, regular, circular, quincuncial pores. Abdomen cylindrical, smooth, nearly hyaline, with
very scarce, irregular, widely scattered pores. Peristome with a corona of fifteen to twenty broad,
lamellar, vertical, truncate feet, about as long as the abdomen.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'08 ; breadth, a 0'03, b 01, c 0'08.

Habitat. — Fossil in Barbados.

8. Calocyclas hyalogaster, n. sp.

Shell with two sharp strictures. Length of the three joints =1:4:6, breadth = 1:4:3.
Cephalis subspherical, with a conical horn of twice the length. Thorax subspherical, thorny, with
regular, circular pores. Abdomen cylindrical, smooth, quite hyaline, without any pores. Peristome
with a corona of twelve broad, lamellar, vertical, truncate feet, half as long as the abdomen.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 012; breadth, a 0'02, b 0'08, c 0'06.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

9. Calocyclas erinaceus, Haeckel.

Cycladophora erinaceiis, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68,
Taf. xviii. fig. 2.

Shell with two sharp strictures. Length of the three joints = 2:9:5, breadth = 3:9:5.
Cephalis subspherical, rough, with a short and broad conical horn of half the length. Thorax ovate,
densely covered with conical spines as long as the horn, and with regular, circular, quincuncial pores.
Abdomen cylindrical, smooth, with irregular roundish pores of different sizes. Peristome with
twelve to fifteen vertical, broad, lamellar, truncate feet half as long as the abdomen (in Ehrenberg's
figure these are broken off).

Dimensions. — Length of the three joints, a 0'04, b 018, c 01 ; breadth, a 0'06, b 018, c 01.

Habitat. — Fossil in Barbados.

1384 THE VOYAGE OF H.M.S. CHALLENGER.

10. Calocyclas gigas, Haeckel.

Cycladophora gigas, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf. xviii.
fig. 1.

Shell with two sharp strictures. Length of the three joints = 2:5:3, breadth = 2:6:4.
Cephalis subspherical, rough, with a short and broad conical horn of half the length. Thorax
subspherical, campanulate, thorny, with subregular, circular pores (smaller and more numerous than
in the preceding). Abdomen cylindrical, smooth, with a small number of sparsely disposed,
roundish, irregularly scattered pores. Peristome with twenty to thirty short, lamellar, truncate,
vertical feet about half as long as the cephalis.

Dimensions. — Length of the three joints, a 0'06, b 015, c 0'09 ; breadth, a 0'06, I 018, c 012.

Habitat. — Fossil in Barbados.

Subgenus 3. Calocycloma, Haeckel.
Definition. — Thorax smooth ; abdomen spiny or thorny.

11. Calocyclas casta, n. sp. (PL 73, fig. 10).

Shell ovate, with two sharp strictures. Length of the three joints = 1:2:8, breadth = 2:4:8.
Cephalis hemispherical, with a strong pyramidal horn of twice the length. Thorax campanulate,
smooth, with small, regular, circular pores. Abdomen inflated, subspherical, covered with large
conical spines, and large intervening circular pores (four times as broad as the thoracic pores).
Mouth constricted, only one-third as broad as the abdomen, with a peristome of nine to twelve
conical vertical feet as long as the abdominal spines. (In the specimen figured they were broken off'.)

Dimensions. — Length of the three joints, a 0'03, b O04, c 015 ; breadth, a 0'04, b 0'08, c 015.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

12. Calocyclas pudica, n. sp.

Shell ovate, with two distinct strictures. Length of the three joints =1:3:8, breadth = 1:4:6.
Cephalis subspherical, with a conical horn of three times the length. Thorax and abdomen nearly
of the same shape as in the preceding species, but more slender, and the regular, circular pores of
the abdomen only twice as broad as the thoracic pores. Conical spines of the abdomen only half
as large, but more numerous. Peristome constricted, half as broad as the abdomen, with sixteen to
twenty short, conical, vertical feet as long as the cephalis.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 016 ; breadth, a 0'025, b 0'08, c 012.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 4. Calocycloma, Haeckel.
Definition. — Thorax and abdomen spiny or thorny.

REPORT ON THE RADIOLARTA. 1385

13. Calocyclas parthenia, n. sp. (PI. 74, fig. 1).

Shell nearly ovate, with thorny surface, and two slight strictures. Length of the three joints =
1:2:4, breadth = 2:4:5. Cephalis hemispherical, armed with numerous short, conical thorns,
and with a pyramidal, very large, vertical horn as long as the thorax, and on the basal half as broad
as the cephalis. Thorax hemispherical, separated by a slight stricture from the broader, barrel-
shaped abdomen, which is a little constricted at the mouth. Teeth of the coronal about twenty,
triangular, short, little divergent. Pores circular, somewhat irregular in size, three to four times
as broad as the bars, in all three joints nearly of the same shape.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c Oil ; breadth, a 0'05, I 01, c 012.

Habitat. — Indian Ocean, Cocos Islands, surface (Eabbe).

14. Calocyclas aspasia, n. sp.

Shell ovate, conical, with two deep strictures. Length of the three joints =1:3:4, breadth =
1:4:5. Cephalis subspherical, with a conical horn of twice the length. Thorax and abdomen
nearly of the same shape as in the preceding species, but covered with longer conical spines, less
numerous, and twice as long as the diameter of the subregular, circular pores. Mouth more con-
stricted, and armed with a coronal of twelve to sixteen broad, lamellar feet, as long as the cephalis,
and similar to those of Calocyclas puella (PI. 74, fig. 5).

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'08 ; breadth, a 0'03, b 0'08, c 01.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

15. Calocyclas monumentum, n. sp. (PI. 73, fig. 9).

Shell nearly conical, with two very deep strictures, everywhere covered with long, bristle-shaped,
divergent spines, about as long as the thorax. Length of the three joints = 1:2:2, breadth =
1:4:6. Cephalis nearly spherical, with a very large, three-sided pyramidal horn of twice the
length. Thorax and abdomen of similar form, campanulate, with a lower cylindrical, and an
upper truncate, conical part. Pores irregular, roundish, in the smaller thorax of slightly different
sizes, in the larger abdomen three to four transverse rows of larger pores (six to eight in each row)
are separated by numerous much smaller pores. Peristome wide open, with a coronal of twelve
large, triangular, vertical feet, nearly as long as the abdomen ; in the base of each foot a large,
roundish, triangular pore.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 0'6 ; breadth, a 0'04, b 012, c 018.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 606. Clathrocyclas,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — The oph or mi da (vel Tricyrtida multiradiata aperta) with a simple
corona of terminal feet around the dilated mouth. Abdomen dilated, truncate-conical,
or discoidal. No ribs in the shell-wall.

1 Clathrocyclas = Fenestrated female robe ; n^t^a, *"***;•

(ZOOL. CHALL. EXP. — PABT XL. — 1886.) Rr 174

1386 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Clathrocydas differs from the preceding closely allied Calocyclas in the
dilated mouth and the flatter form of the abdomen, which is usually truncate, conical, or
nearly discoidal. The conical thorax is often separated from the flat abdomen by an
elegant ribbon of small quadrangular pores. The feet or teeth of the terminal corona are
divergent, or even horizontally expanded, whilst in Calocyclas they are usually vertical
or somewhat convergent.

Subgenus 1. Clathrocyclia, Haeckel.

Definition. — Shell highly conical, often ovate or slenderly campanulate. Cephalis
commonly with a single horn.

1. Clathrocydas principessa, n. sp. (PI. 74, fig. 7).

Shell ovate, with two distinct strictures. Length of the three joints =1:2:1, breadth =
1:2:2. Cephalis hemispherical, large, with a pyramidal, occipital horn of the same length.
Thorax subspherical, with irregular, circular pores, about as broad as the bars. Abdomen short,
widely open with a single transverse row of circular pores, and a coronal of twelve triangular,
divergent feet, as long as the abdomen.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 0*03 ; breadth, a 0'04, I OD8, c 0'09.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Clathrocydas basilea, (PI. 74, fig. 6).

Shell campanulate, with two deep strictures. Length of the three joints = 2:5:3, breadth =
3:7:9. Cephalis hemispherical, with an ovate, oblique horn of the same length. Thorax hemi-
spherical, with subregular, circular pores of the same breadth as the bars. Abdomen short, with
two transverse rows of the same pores, and with a coronal of sixteen to twenty ovate, divergent
feet, as long as the horn.

Dimensions. — Length of the three joints, a 0'02. b 0'05, c 0'03 ; breadth, a 0'035, b 0'07, c 0'09.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

3. Clathrocydas jimbriata, Haeckel.

1 Halicalyptra fimlriata, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. ii.
fig. 11.

Shell campanulate, with two deep strictures. Length of the three joints = 1 : 3 : 1, breadth =
1:3:5. Cephalis hemispherical, with a conical horn of twice the length. Thorax hemispherical, in
the upper half hyaline, without pores, in the lower half with four to six transverse rows of sub-
regular, circular pores. Abdomen short, suddenly dilated, with one or two transverse rows of larger

REPORT ON THE RADIOLARIA. 1387

ovate pores (six to eight in one row), and with a coronal of twelve to fifteen divergent, slender,
curved feet, as long as the cephalis. (In the figure of Ehrenberg, seen half from below, the
cephalis is not represented.)

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'02 ; breadth, a 0'02, b 0'06, c 01.

Habitat. — Fossil in Barbados.

4. Clathrocyclas collaris, n. sp. (PI. 74, fig. 8).

Shell subconical, with two indistinct strictures. Length of the three joints = 1:1:2, breadth =
1:2:3. Cephalis hemispherical, with a triangular prismatic horn three times the length. Thorax
truncate, conical, with a single transverse row of circular pores, each of which is placed in the lower
end of an oblong, lanceolate, longitudinal furrow ; collar composed of fifteen to twenty such furrows.
Abdomen inflated, with four to six transverse rows of circular pores, and with a coronal of nine
triangular, divergent feet, longer than the collar.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 0'06 ; breadth, a 0'03, b 0'06, c 0'09.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

5. Clathrocyclas puella, Haeckel.

Podocyrtis puella sinensis, Ehrenberg, 1875, Abhandl. d. k. Akad. d. "VViss. Berlin, p. 82,
Taf. xiv. fig. 3.

Shell subconical, with two indistinct strictures. Length of the three joints = 1:1:2, breadth

= 1:2:3. Cephalis hemispherical, with a pyramidal horn of twice the length. Pores siibregular,

circular, quincuncial, in the dilated abdomen (with four to five transverse rows), twice to three times

as large as in the short thorax (with two to three rows). Coronal of the wide peristome with fifteen

to twenty short, triangular, divergent feet, about as long as the cephalis.

Dimensions. — Length of the three joints, a 0'02, b 0'02, c 0'04 ; breadth, a 0'02, b 0'04, c 0'06.

Habitat. — Fossil in Barbados.

6. Clathrocyclas domina, Haeekel.

Podocyrtis domina sinensis, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 82,
Taf. xiv. fig. 4.

Shell subconical, with two slight strictures. Length of the three joints = 1:2:4, breadth =
1:3:4. Cephalis ovate, with a conical horn of the same length (and sometimes with some little
accessory thorns at its base). Pores subregular, circular, quincuncial, in the dilated abdomen (with
six to eight transverse rows), twice to four times as large as in the hemispherical thorax (with four
to six rows). Coronal of the wide persistome with nine to twelve short, triangular, divergent feet,
half as long as the cephalis (in Ehrenberg's figure incomplete).

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'02, b 0'06, c O'OS.

Habitat. — Central Pacific, Stations 263 to 268, depth 2650 to 3000 fathoms ; also fossil in
Barbados.

1388 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 2. Clathrocycloma, Haeckel.

Definition. — Shell flatly conical, often widely campanulate, or nearly discoidal.
Cephalis commonly with two or more horns

7. Clathrocyclas alcmence, n. sp. (PL 59, fig. 6).

Shell conical, with two indistinct strictures. Length of the three joints = 2 : 10 : 1, breadth =
2 : 12 : 14. Cephalis hemispherical, with two divergent, pyramidal horns ; frontal horn as long as
the cephalis, occipital horn of twice the length. Thorax conical, with large hexagonal meshes,
increasing gradually in size towards the short abdomen, which is represented only by a single
circular girdle of small, square, abdominal pores. Coronal of the peristome with twenty to thirty
triangular, divergent, nearly horizontal feet, as long as the cephalis.

Dimensions. — Length of the three joints, a O02, b 01, c O'Ol ; breadth, a 0'02, I 012, e 014.

Habitat — Central Pacific, Station 272, depth 2600 fathoms.

8. Clathrocyclas europce, n. sp. (PL 59, figs. 11, 12).

Shell conical, almost of the same form as the preceding nearly allied species, differing from it
in the concave (not straight) outline of the flatter conical thorax, in the more rounded form of its
pores, and in the subspherical form of the cephalis, bearing only a single conical horn of the
same length. Length of the three joints = 2:8:1, breadth = 2 : 12 : 14. In fig. 11 the cephalis
is broken off, so that the four cortinar pores are visible (two smaller jugular and two larger cardinal
pores, separated by two eoracal beams).

Dimensions. — Length of the three joints, a 0"02, b 0'08, c O'Ol ; breadth, a 0'02, b 012, c 014.

Habitat. — Mediterranean, Corfu (Haeckel), surface.

9. Clathrocyclas semeles, n. sp. (PL 58, fig. 5).

Shell conical-campanulate, with two distinct strictures. Length of the three joints = 2:8: 1,
breadth = 2:8:10. Cephalis hemispherical, with three divergent, conical horns (the caudal horn,
directed downwards, much longer than the occipital and frontal horns). Pores of the thorax large,
roundish. Abdomen (as in the two preceding species) with only a single circle of forty to fifty
small square pores. Coronal with about the same number of short, triangular, almost horizontally
divergent feet.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c O'Ol; breadth, a 0'02, b 0'08, c 01.

Habitat. — Central Pacific, Station 271, surface.

10. Clathrocyclas danaes, n. sp. (PL 59, figs. 13, 14).

Shell flatly conical, with straight outline (as in Clathrocyclas alcmence, PI. 59, fig. 6). -Length of
the three joints =1:5:1, breadth = 2:8:1. Cephalis hemispherical, with a single, short, conical,

REPORT ON THE RADIOLARIA. 1389

oblique horn (broken off in the specimen figured). Pores of the thorax polygonal, increasing
gradually in size towards the girdle (in three to four circles.) Abdomen nearly horizontally
expanded, with two rows of pores, the inner with very small and numerous square pores, the outer
with twenty to thirty much larger quadrangular pores. Coronal of the peristome with the same
number of short, divergent feet, alternating with the larger pores.

Dimensions. — Length of the three joints, a 0'02, b 01, c 0'02; breadth, a 0'04, b 015, c 0'2.

Habitat. — North Atlantic, Canary Islands (Lanzerote), Station 354, surface.

11. Clathrocyclas jonis, n. sp. (PI. 59, fig. 9).

Shell campanulate, with two slight strictures. Length of the three joints = 1:5:2, breadth =
1:6:8. Cephalis small, hemispherical, with two divergent, conical horns of nearly equal length.
Pores of the thorax polygonal, increasing in size towards the girdle ; in the upper half filled up by
an extremely fine and delicate cobweb-like network. Abdomen with two rows of pores, of the
same shape as in the preceding species, also with equal coronal.

Dimensions. — Length of the three joints, a 0'02, b 01, c 0'03 ; breadth, a 0'02, b 012, c 016.

Habitat. — Central Pacific, Station 274, surface.

12. Clathrocyclas latonce, n. sp. (PI. 59, fig. 7).

Shell campanulate, very similar to the preceding species, but flatter and different in the larger
cephalis, bearing only a single oblique horn. All the polygonal pores of the thorax are filled out by
delicate cobweb-like network. Length of the three joints = 1:3:1, breadth = 1:4:6. Abdomen
with three circular rows of quadrangular pores ; first very small and numerous, second of median
size, third very large. Coronal with thirty to forty short triangular feet.

Dimensions. — Length of the three joints, a 0'03, b 0'08, c 0'03 ; breadth, a 0'03, b 012, c 018.

Habitat. — Tropical Atlantic, Station 325, surface.

13. Clathrocyclas coscinodiscus, n. sp. (PI. 58, figs. 3, 4).

Shell flatly campanulate, with two distinct strictures. Length of the three joints = 1:5:2,
bread th = l : 8 : 10. Cephalis hemispherical, with two divergent, pyramidal horns of the same
length. Thorax with concave outline, with numerous hexagonal pores, gradually increasing in size
towards the girdle, except the outermost row (inside the girdle), which is composed of very small,
square pores. Abdomen (outside the girdle) with three rows of pores ; first with small, second
with median, third with large pores. Coronal with eighty to one hundred short, divergent feet.

Dimensions.— Length of the three joints, a 0'02, b 01, c 0'03 ; breadth, a 0'025, b 016, c 0'2.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

1390 THE VOYAGE OF H.M.S. CHALLENGER.

14. Clathrocyclas cassiopeice, n. sp. (PI. 59, fig. 5).

Shell flatly campanulate, with two slight strictures. Length of the three joints = 2:4:3, breadth
= 2:6:8. Cepbalis ovate, thorny, with a pyramidal horn of the same length, and several smaller
accessory horns. Thorax smooth, with irregular, polygonal pores of nearly equal size. Abdomen
spiny, with three to four irregular rows of similar pores. Coronal with sixty to ninety or more
irregularly and obliquely divergent feet, little larger than the abdominal spines.

Dimensions. — Length of the three joints, a 0'04, b 0'08, c 0'06 ; breadth, a 0'03, b 012, c 016.

Habitat. — Indian Ocean, Madagascar, Eabbe, surface.

Genus 607. Lamprocyclas,1 Haeckel, 1881, Prodromus, p. 434.

Definition — T heophormida (vel Tricyrtida multiradiata aperta) with a double
corona of solid terminal feet around the mouth. No ribs in the shell-wall.

The genus Lamprocyclas differs from Calocyclas, its ancestral form, in the duplica-
tion of the terminal corona. Usually the feet or teeth of the lower corona are
convergent and curved inwards, whilst the teeth of the upper corona are divergent and.
curved outwards. Sometimes above the latter a third corona begins to be developed.
The whole shell is more or less conical, very thick -walled, with a large and stout apical
horn.

Subgenus 1. Lamprocydia, Haeckel.
Definition. — Feet of the peristome simple, not branched.

1. Lamprocyclas nuptialis, n. sp. (PI. 74, fig. 15).

Shell campanulate, nearly smooth, with two slight strictures. Length of the three joints =
1:2:2, breadth = 1:3:4. Cephalis ovate, with a very large, three-sided prismatic horn, nearly as
long as the shell. Thorax and abdomen gradually dilated, with regular, circular, double-edged
pores. Outer coronal of the peristome with twelve to fifteen divergent feet, inner with as
many subvertical, triangular, little curved feet, about as long as the cephalis.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c OD6 ; breadth, a 0'03, b 0'09, c 012.

Habitat. — Central Pacific, Station 2*71, depth 2425 fathoms.

2. Lamprocyclas maritalis, n. sp. (PI. 74, figs. 13, 14).

Shell campanulate, very similar to the preceding species in form and fenestration, but not so
slender and with different peristome. Length of the three joints = 4:5:6, breadth = 4 : 10 : 13.
Cephalis subspherical, with a very stout, pyramidal horn of twice the length, the edges of which are

1 Lamprocydas = Splendid female robe ; Kctftngos, xi/xAaj.

REPORT ON THE RADIOLARIA. 1391

spirally convoluted. Outer coronal of the peristome with twelve to fifteen short, divergent feet,
inner with as many convergent, longer feet.

Dimensions. — Length of the three joints, a 0'04, b 005, c 0'06 ; breadth, a 0'04, b 01, c 013.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Lamprocyclas deflorata, n. sp. (PL 74, fig. 10).

Shell ovate, smooth, with deep collar, but indistinct lumbar stricture ; very similar to the two
preceding species, but with different horn and peristome. Length of the three joints = 3:5:8,
breadth = 3 : 10 : 13. Cephalis subspherical, with a pyramidal horn of twice the length, the three
faces of which are deeply concave. Thoracic pores half as large as the abdominal, both subregular,
double-edged. Outer coronal of the wide peristome with nine short, triangular, subvertical feet,
inner with nine larger, horizontal feet, lying in the plane of the wide mouth.

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'08 ; breadth, a 0'03, b 01, c 013.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

4. Lamprocyclas saltatricis, n. sp. (PL 74, fig. 16).

Shell conical, rough, with two slight strictures. Length of the three joints = 2:2:3, breadth =
1:4:6. Cephalis ovate, with a large, prismatic horn, half as long as the shell. Pores subregular,
circular, not double-edged, three times as broad in the inflated abdomen as in the hemispherical
thorax. Outer coronal of the wide peristome with twelve to fifteen divergent feet, inner with
fifteen to twenty conical feet, which are curved inwards nearly horizontally.

Dimensions. — Length of the three joints, a 0'04, b 0'05, c 0'07 ; breadth, a 0'025, b 01, c 015.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

5. Lamprocyclas regince, n. sp. (PL 74, figs. 11, 12).

Shell campanulate, with two slight strictures. Length of the three joints = 2:3:3, breadth =
2:5:6. Cephalis subcylindrical, with about fifteen longitudinal rows of circular pores, separated
by prominent, parallel crests, and with a very large sword-like horn, nearly as long as the shell.
Thorax hemispherical, smooth, with elegant, circular, hexagonally-framed pores. Abdomen dilated,
with similar but larger pores, armed with hook-shaped spines. The two inferior rows of these
hooks form the double coronal of the peristome ; the feet of the outer are curved downwards, of
the inner inwards.

Dimensions. — Length of the three joints, a 0'04, b 0'06, c 0'06 ; breadth, a 0'04, b 01, c 012.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

6. Lamprocyclas cegles, Haeckel.

Podocyrtis cegles, Ehrenberg, 1854, Mikrogeol., Taf. xxxv. B. B iv. fig. 18.

Shell campanulate, conical, thorny, with two deep strictures. Length of the three joints =
3:5:5, breadth = 3:8:11. Cephalis ovate, with a stout, three-sided prismatic horn of twice the

1392 THE VOYAGE OF H.M.S. CHALLENGER.

length. Pores subregular, circular, twice as broad in the inflated abdomen as in the campanulate
thorax, and four times as broad as in the cephalis. Outer coronal of the wide peristome with
fifteen to twenty conical, divergent feet, inner coronal with a smaller number of vertical, parallel,
divergent feet.

Dimensions. — Length of the three joints, a O03, I 0'05, c 0'05; breadth, a 0'03, b 0'08, c Oil.

Habitat. — North Atlantic, depth 1400 fathoms (Berrymann).

Subgenus 2. Lamprocycloma, Haeckel.
Definition. — Feet of the peristome forked or branched.

7. Lamprocydas bajaderce, n. sp.

Shell campanulate, very similar to the preceding species, but with stronger spines on the
abdomen and with different peristome. Length of the three joints = 2:2:3, breadth = 2:6:8.
Cephalis equal to that of Lamprocydas maritalis (PI. 74, figs. 13, 14). Outer coronal of the
peristome with fifteen to twenty divergent, pyramidal feet, half as long as the horn ; inner coronal
with as many longer, vertical feet, which are irregularly forked or branched.

Dimensions. — Length of the three joints, a 0'04, b 0'04, c 0'06 ; breadth, a 0'04, b 012, c 016.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

Genus 608. Diplocyclas,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — T heophormida (vel Tricyrtida multiradiata aperta) with a double
corona of radial solid feet, an upper around the lumbar stricture, a lower around the
mouth. No ribs in the shell- wall.

The genus Diplocyclas differs from all the other Theophormida in the possession of a
double coronal of radial teeth, an upper between thorax and abdomen, and a lower around
the terminal mouth of the latter; it may be regarded as an Anthocyrtis, which has
formed an abdomen, and repeated the terminal armature. The cephalis bears a single or
double apical horn.

1. Diplocyclas bicorona, n. sp. (PL 59, fig. 8).

Shell slender, campanulate. Length of the three joints =1:3:2, breadth = 1:4:4. Cephalis

subspherical, with two divergent horns ; the occipital of the same length and forked, the frontal

shorter and simple. Thorax campanulate, with six to eight transverse rows of double-edged

roundish pores of increasing size. Abdomen cylindrical, with three transverse rows of large poly-

1 Diplocyclas = Female robe with a double girdle ; 3<VXo'os, xt/xA«j.

EEPORT ON THE RADIOLARIA. 1393

gonal pores, and a terminal row of very small square pores. Lumbar and terminal coronals of similar
shape, each with twenty to thirty short divergent feet.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 004; breadth, a 0'025, b 0'08, c 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Diplocyclas bicincta, n. sp.

Shell campanulate, in general of the same form as, and similar fenestration to, the preceding species
but not so slender, and with different proportions. Length of the three joints = 1:4:2, breadth =
2:5:5. Cephalis hemispherical, with a single, conical, simple horn. Pores of the thorax hexa-
gonal, of increasing size (in eight to ten transverse rows). Abdomen with smaller square pores (in
four to six rows). The two coronals of the same shape as in PL 59, fig. 8.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'04 ; breadth, a (V04, I 01, c 01.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

3. Didocyclas bizonalis, n. sp.

Shell snbconical, with indistinct collar and distinct lumbar stricture. Length of the three
joints =1:2:3, breadth = 1:3:4. Cephalis hemispherical, with two divergent conical horns of
equal size. Thorax conical, with small, irregular, roundish, double-edged pores, and a terminal
corona of about nine very large pores. Abdomen truncate, conical, with three to four transverse
rows of roundish, quadrangular, very large pores. Lumbar and terminal coronals of similar shape,
each with twelve to fifteen triangular divergent feet.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'06 ; breadth, a 0'02, b 0'06, c 0'08.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

%

Subfamily 2. THEOPH^NIDA, Haeckel, 1881, Prodromus, p. 437.

Definition. — Phor m ocy rtida with the basal mouth of the shell fenestrated
(vel Tricyrtida multiradiata clausa).

Genus 609. Hexalatractus,1 n. gen.

Definition. — T heophasnida (vel Tricyrtida multiradiata clausa) with six lateral
wings on the abdomen.

The genus Hexalatractus, and the following genus Theophcena, represent together
the small subfamily Theophaenida, or those Tricyrtida in which the terminal mouth of
the shell is closed by lattice-work, and six or nine lateral apophyses indicate a multi-
radiate structure. The shell is more or less ovate or spindle-shaped, tapering towards

1 Hexalatract us = Spindle with six wings ; e|«x«, akjaxTOf.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr ] 75

1394 THE VOYAGE OF H.M.S. CHALLENGER.

both poles, and resembles greatly the triradiate Rhopalocanium. It may be derived
from the latter by interpolation of three secondary or interradial wings between the
three primary or perradial apophyses.

1. Hexalatractus sexalatus, n. sp.

Shell ovate, smooth, with two distinct strictures. Length of the three joints = 3:6:9, breadth
= 4:9:8. Cephalis subspherical, with a pyramidal horn of twice the length. Thorax campanu-
late ; abdomen inversely conical ; both with subregular, circular pores. Six divergent wings arise,
beginning from the collar stricture, from the upper half of the shell, with broad triangular base ;
they are little curved downwards, with the convexity outside, and gradually tapering towards the
distal end ; the latter lies in the same horizontal plane as the basal apex of the abdomen.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c O09 ; breadth, a 0'04, I 0'09, c 0-08.

Habitat. — Central Pacific, Stations 263, depth 2650 fathoms.

2. Hexalatractus fusiformis, n. sp. (PI. 68, fig. 13).

Shell rough, nearly spindle-shaped, with sharp collar and slight lumbar stricture. Length of the
three joints = 2:5:12, breadth = 3:8:7. Cephalis hemispherical, with a conical horn of the same
length. Thorax hemispherical, with regular, circular, hexagonally-framed pores. Abdomen
inversely conical, with irregular, roundish pores. From the upper half of the abdomen arise, with
broad triangular base, six divergent wings, which are nearly straight, and slightly fenestrated at
the base ; their conical distal ends do not reach the horizontal plane, in which the basal apex of
the abdomen lies.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 012 ; breadth, a 0'03, b 0'08, c 0'07.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 610. Theophcena,1 Haeckel, 1881, Prodromus, p. 437.

Definition. — Theophsenida (vel Tricyrtida multiradiata clausa) with nine
lateral wings on the abdomen.

The genus Theophcena, differs from the preceding six-radiate Hexalatractus in the
possession of nine lateral wings, and may be derived from the triradiate Rhopalocanium
by interpolation of six secondary wings between the three primary apophyses.

1. TJieophcena corona, n. sp. (PI. 70, fig. 12).

Shell rough, nearly spindle-shaped, with two sharp strictures. Length of the three joints =
4:9: 16, breadth = 5 : 12 : 10. Cephalis hemispherical, very thick-walled, with a conical horn of

1 Theophcena, = Divine shell ; Ms, /fecinct.

REPORT ON THE RADIOLARIA. 1395

the same length; both covered with numerous small dimples and spinules. Thorax campanulate •
abdomen inversely conical ; both with regular, circular pores. Thorax with nine thin curved ribs,
which in the upper half of the abdomen arise as nine large feet, which are strongly compressed and
curved (with the convexity outwards) ; their distal ends form nine ovate spinulate cones, and lie in
the same horizontal plane as the basal apex of the abdomen.

Dimensions. — Length of the three joints, a 004, b 0'09, c 016 ; breadth, a 0'05, J 012, c 01.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

2. TJieophcena nonaria, n. sp.

Shell thorny, ovate, with two slight strictures. Length of the three joints = 1:4:5, breadth
= 1:5:4. Cephalis subspherical, with a conical horn of half the length. Thorax subspherical,
with regular, circular pores and conical spines. Abdomen ovate, smooth, with irregular, roundish
pores. In the upper half of the thorax descend nine straight, little divergent ribs, which in the
lower half become free, and represent nine slender, conical wings ; their distal ends do not reach the
horizontal plane in which the basal end of the abdomen lies.

Dimensions.- — Length of the three joints, a 0'03, b 012, c 015; breadth, a 0'03, b 014, c 012.

Habitat. — South of Australia, Station 160, surface.

Family LXV1I. THEOCYRTIDA, n. fam.

Tlieocorida et Theocapsida, Haeckel, 1881, Prodromus, pp. 434, 436.

Definition. — T ricyrtida eradiata. Cyrtoidea with a three-jointed shell,
divided by two transverse constrictions into cephalis, thorax, and abdomen, without
radial apophyses.

The family Theocyrtida, composed of the Theocorida and Theocapsida of my
Prodromus, comprises those Cyrtoidea in which the lattice-shell is three-jointed,
and bears no external radial apophyses. The two subfamilies differ in the shape of the
terminal mouth, which in the Theocorida is a simple wide opening, in the Theocapsida
closed by a lattice-plate. The phylogenetic origin of the Theocyrtida may be found
either in the Podocyrtida or in the Sethocyrtida ; they may have been derived from the
former by reduction and loss of the three primary apophyses, or from the latter by
development of an abdomen.

The number of species in this group is very large, and many belong to the most
common and widely distributed Cyrtoidea. A great number of living and fossil
species have already been described by Ehrenberg, the majority being disposed in his
genera Lithocampe and Eucyrtidium.

The number of genera, however, is comparatively small, and their distinction
difficult, since the form of the shell presents no striking differences.

1396

THE VOYAGE OF H.M.S. CHALLENGER.

It exhibits all possible passages, from a flatly expanded or nearly discoidal form
with a wide open mouth, to a conical or cylindrical, and by constriction of the terminal
mouth to an ovate or spindle-shaped form. By complete closure of the mouth the Theo-
capsida arise. In some genera remarkable traces of the original triradial structure are
preserved. The most interesting of these forms is Axocorys, with an internal axial
columella, which bears a number of verticils, each with three radial branches.

Synopsis of the Genera of Theocyrtida.

I. Subfamily

Theocorida.
Terminal mouth of
the abdomen a
simple wide open-
ing.

Abdomen gra-
dually dilated

Abdomen f with h .
flatly ex- I

panded, dis- 1 ,T ,
. , ', No horn,

COlufu

611. Tlieocalyptra.
612. Cecryphalium.

towards the •

L

wide open
mouth.

Abdomen j One horn, . . .

613. Theoconus.

• 1 "\

( Two or more horns, .

614. Lophoeonus.

f Thorax and abdomen of

Abdomen

A single apical equal breadth,

615. Tbeocyrtis.

cylindrical, of

horn on the •{

nearly equal

cephalis. | Thorax much broader than

breadth

[ the tubular abdomen, .

616. Theosyringium.

throughout its *

whole length.

Two horns or a bunch of horns on the

Mouth trun-

cephalis,

617. Lopltocyrtis.

cate.

__ No horn on the cephalis, ....

618. Tricolocampe.

{Shell-cavity without an in-

ternal columella, .

619. Theocorys.

Abdomen

ovate or in-

Shell-cavity with an axial

versely conical, j

columella,

620. Axocorys.

Mouth more or '

less con-

Two horns or a bunch of horns on the

stricted.

cephalis,

621. Lophocorys.

I

No horn on the cephalis, ....

622. Theocampe.

II. Subfamily

Theocapsida,

Terminal mouth
closed by a lat-
tice-plate.

No latticed septum between
thorax and abdomen.

An apical horn,
No horn on the cephalis, .
A complete latticed septum between thorax and abdomen,

623. Theocapsa.

624. Tricolocapsa.

625. Phrenocodon.

Subfamily 1. THEOCORIDA, Haeckel, 1881, Prodromus, p. 434.

Definition. — T heocyrtida with the basal mouth of the shell open (vel Tricyrtida
eradiata aperta).

REPORT ON THE RADIOLARIA. 1397

Genus 611. Theocalyptra,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with discoidal or flatly
expanded abdomen. Cephalis with a single apical horn, or with two divergent horns.

The genus Theocalyptra, and the following closely allied genus Cecryphalium,
differ from all the other Theocorida in the flattened form of the cap-shaped or nearly
discoidal shell. The abdomen specially is quite flat, often horizontally expanded, and
like the marginal brim of a flat hat. They may be derived from the Dicyrtida Setho-
cephalus by the development of an abdomen, or from Corocalyptra by loss of the
collar wings. The network is usually very delicate, as in the latter. The cephalis of
Theocalyptra bears one or two horns.

1. Theocalyptra veneris, n. sp.

Shell flatly campanulate, very delicate and fragile, very similar to Hucephryphaliis agnesce
(PI. 59, fig. 3), but without collar spines. Length of the three joints = 1:4:2, breadth = 1:7:9.
Cephalis hemispherical, with a single bristle-shaped horn of twice the length. Thorax sub-
conical, separated from the natter abdomen by a deep stricture, with thin bars, and large, subregular,
hexagonal meshes, increasing in size towards the smooth mouth-edge.

Dimensions. — Length of the three joints, a 0'02, b 0'07, c 0'04 ; breadth, a 0'025, b 015, c 01.

Habitat. — Cosmopolitan ; Atlantic, Indian Pacific, many stations, surface.

2. Theocalyptra orci, Haeckel.

Halicalyptra orci, Ehrenberg, 1872, Abhandl. d. k Akad. d. Wiss. Berlin, p. 293, Taf. x.
figs. 9, 10.

Shell flatly campanulate, very similar to the preceding species in general' form and fenestration,
but flatter and smaller, with different proportions. Length of the three joints = 7:2:1, breadth =
1:6:8. Cephalis hemispherical, very small, with two divergent, bristle-shaped horns of the same
length. Abdomen nearly horizontally expanded.

Dimensions. — Length of the three joints, a 0'015, b 0'04, c O'Ol ; breadth, a 0'02, b 012, c 016.

Habitat. — Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).

3. Theocalyptra discoides, Haeckel.

Cycladophora discoides, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 68, Taf.

xviii. fig. 4.

Shell flatly campanulate, similar to the two preceding species, but not so delicate, with thicker
bars, and roundish, not hexagonal meshes. Length of the three joints = 1:2:2, breadth = 3:6:9.

1 Theocalyptra = Divine veil ; ifo;,

1398 THE VOYAGE OF H.M.S. CHALLENGER.

Cephalis large, trilobed, with a short, oblique horn of half the length. Thorax campanulate, conical,
separated from the abdomen by a circle of smaller pores and a deep stricture. Abdomen flat, dis-
coidal, with three circles of larger pores.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'04 ; breadth, a 0'06, b 012, c 018.

Habitat. — Fossil in Barbados.

4. Theocalyptra cornuta, Haeckel.

Carpocanium cornutum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 287, Taf. ii.

fig. 9.

Halicalyptra cornuta, Bailey, 1856, Amer. Journ. Sci. and Arts, vol. xxii. p. 5, pi. i. figs. 13, 14.
Lophophcena cornuta, Haeckel, 1862, Monogr. d. Radiol., p. 299.

Shell campanulate-conical, with two sharp strictures. Length of the three joints =1:3:1,
breadth = 1:4:5. Cephalis subspherical, with two stout, pyramidal, divergent horns of twice the
length. Thorax campanulate, with eight to ten transverse rows of roundish or nearly square pores,
increasing in size towards the abdomen, which is flatly expanded, nearly discoidal, separated by a
circle of smaller pores ; the last circle of pores (on the margin) is larger.

Dimensions. — Length of the three joints, a 0'025, b 0'09, c 0'03 ; breadth, a 0'03, b 012, c 016.

Habitat. — Arctic Ocean, Kamtschatka (Bailey), Greenland (Ehrenberg).

Genus 612. Cecryphalium,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with diseoidal or flatly
expanded abdomen. Cephalis without horn.

The genus Cecryphalium has the same flat, conical, or nearly discoidal shell as the
preceding Theocalyptra, its ancestral genus, but differs from it in the complete absence
of horns on the cephalis.

1. Cecryphalium lamprodiscus, n. sp. (PI. 58, fig. 2).

Shell flatly conical, with two slight strictures. Length of the three joints = 1:3:2, breadth =
1 : 7 : 11. Cephalis roundish, very small. Thorax conical, with straight lateral outline ; its pores
irregular, polygonal, increasing in size towards the girdle. Abdomen little flatter than the thorax,
forming its direct prolongation, with five to six circular, concentric rows of pores ; the first row
formed by sixty to eighty very large, oblongish, quadrangular pores, the second row by very small,
the third again by larger pores ; the outmost rows by very small and numerous pores.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'04 ; breadth, a 0'02, b 014, c 0'22.

Habitat. — Central Pacific, Station 272, surface.

1 Cecryphalium — Net-cap ; xexjixpi A«H<.

REPORT ON THE RADIOLARIA. 1399

2. Cecryphalium sestrodiscus, n. sp. (PI. 58, fig. 1).

Shell very flat, subconical, nearly discoidal, with two distinct strictures. Length of the three
joints = 1:2:1, breadth = 1 : 8 : 10. Cephalis kidney-shaped, very small. Thorax flat, campanu-
late, with curved lateral outline ; its pores irregular, polygonal, increasing in size towards the girdle.
Abdomen horizontally expanded, like the brim of a hat, with five to six concentric, circular rows of
pores, the pores of the inner rows twice to three times as large as those of the outer rows. (The
inner circle of large, oblongish, quadrangular pores, characteristic of the preceding species, is here
divided into three concentric rings by two circular hoops.)

Dimensions. — Length of the three joints, a, 0"02, I 0'04, c 0'02 ; breadth, a 0'02, b 015, c 0'2.

Habitat.' — Central Pacific, Station 274, surface.

Genus 613. Theoconus,1 n. gen.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with conical abdomen,
gradually dilated towards the wide open mouth. Cephalis with a single horn.

The genus Theoconus, and the following closely allied Lophoconus, differ from the
other Theocorida in the conical or campanulate form of the shell ; the abdomen is a
truncated cone, gradually dilated towards the terminal mouth. The latter is usually
truncated, widely open, sometimes with a slightly constricted peristome. The cephalis of
Theoconus bears a single apical horn.

Subgenus 1. Theocorax, Haeckel.

Definition. — Pores of the thorax and of the abdomen of nearly equal size and
similar form.

1. Theoconus zancleus, Haeckel.

Eucyrtidivm zandeum, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 41, Taf. vi.

figs. 1-3.
Eucyrtidium zandenm, Haeckel, 1862, Monogr. d. Radiol., p. 321.

Shell bell-shaped, nearly conical, smooth. Length of the three joints = 1:3:4, breadth = 1:4:6.
Cephalis nearly spherical, with a stout, straight, pyramidal horn of the same length. Thorax hemi-
spherical. Abdomen gradually increasing in breadth towards the wide truncated mouth. Pores
in all three joints nearly of the same shape, circular, regular, four times as broad as the thin bars.

Dimensions. — Length of the three joints, a 0'027, b 0'08, c 01 ; breadth, a 0'03, b 012, c 018.

Habitat. — Mediterranean (Messina, Naples, Nice, &c.).

' Theoconus = Divine cone; 6i6;,xaa<n.

1400 THE VOYAGE OF H.M.S. CHALLENGER.

2. Theoconus cegceus, Haeckel.

Eucyrtidium cegcuum, Ehrenberg, 1858, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 31 ;

Mikrogeol., 1854, Taf. xxxv. a, xix. a, fig. 5.
Eucyrtidium cegceum, Haeckel, 1862, Monogr. d. Eadiol., p. 329.

Shell flatly bell-shaped, nearly conical. Length of the three joints = 2:5:3; breadth =1:7:8.
Cephalis ovate, with a stout, straight, pyramidal horn of the same length. Thorax flat, bell-shaped.
Abdomen with increasing breadth towards the wide truncated mouth. Pores in all three joints
nearly of the same shape, regular, circular, three times as broad as the bars.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 003; breadth, a 0'016, 6 0'07, c O'OS.

Habitat. — Mediterranean (Coast of Greece and Sicily), surface.

3. Theoconus zanguebaricus, Haeckel.

Eucyrtidium zanguebaricum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293,
Taf. ix. fig. 22.

Shell bell-shaped. Length of the three joints = 1:2:1, breadth = 1:3:4. Cephalis ovate,
with a straight, pyramidal horn of half the length. Thorax hemispherical, without collar stricture,
but with evident girdle stricture. Abdomen dilated towards the wide truncated mouth. Pores
regular, hexagonal, of nearly equal size and form, four to six times as broad as the thin bars.

Dimensions. — Length of the three joints, a 0'03, b O06, c 0'03 ; breadth, a 0'024, b 0'09, c Oil.

Habitat. — Indian Ocean (off Zanzibar), Pullen, depth 2200 fathoms.

4. Theoconus campanulatus, Haeekel.

? Eucyrtidium campanulatum, Ehrenberg, 1858, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 241.
Eucyrtidium campanulatum, Haeckel, 1862, Monogr. d. Eadiol., p. 329.

Shell bell-shaped, smooth. Length of the three joints = 2:3:7, breadth = 3 : 7 : 10. Cephalis
small, spherical, with a short, conical, oblique horn of the same length. Thorax hemispherical, with
an external girdle stricture, prolonged into the truncated, barrel-shaped abdomen, which is a little
constricted at the very wide mouth. Pores small and very numerous, regular, circular, twice to
three times as broad as the bars.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 0'07 ; breadth, a 0'03, b 0'07, c 01.

Habitat. — North Atlantic, Station 352, surface.

5. Theoconus orthoconus, n. sp.

Shell perfectly conical, smooth. Length of the three joints =1:2:3, breadth =1:2:4.
Cephalis hemispherical, with a strong, straight, conical horn of the same length. Thorax conical,
without external girdle stricture, prolonged into the truncated, conical abdomen, which is gradually

EEPOET ON THE RADIOLARIA. 1401

*

dilated into a very wide mouth. Pores small, of nearly equal size and similar form, of the same
breadth as the bars.

Dimensions. — Length of the three joints, a O03, b O'OG, c 0'09 ; breadth, a 003, b 0'06, c 012.

Habitat. — Cosmopolitan ; Atlantic, Pacific ; many stations, at different depths.

Subgenus 2. Theocorbis, Haeckel.

Definition. — Pores of the thorax and of the abdomen of different sizes or dissimilar
forms.

6. Theoconus jovis, n. sp. (PL 69, fig. 4).

Shell bell-shaped, nearly conical Length of the three joints = 5 : 6 : 7, breadth = 4 : 10: 14.
Cephalis nearly cylindrical, large, little curved, with a very large, oblique, pyramidal horn, as long
as the two first joints together. Thorax and the broader abdomen irregularly bell-shaped, dilated
towards the wide mouth. Pores circular, somewhat irregularly disposed, gradually increasing in size
towards the mouth.

Dimensions. — Length of the three joints, a 0-05, b 0'06, c 0'07 ; breadth, a 0'04, b 01, c 014.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

7. Theoconus junonis, n. sp, (PL 69, fig. 7).

Shell nearly conical. Length of the three joints = 4 : 5 : 8, breadth = 3 : 8 : 11. Cephalis ovate,
with a large apical opening at the base of the vertical compressed horn, which has about the same
length. Thorax and the broader abdomen together conical, gradually dilated towards the wide
mouth. Thorax with a bosom-like protuberance on one side. Pores circular, gradually increasing
in size.

Dimensions. — Length of the three joints, a 0'04, b 0'05, c 0'08 ; breadth, a 0'03, b Q'08, c Oil.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

8. Theoconus longicornis, n. sp.

Shell conical, thorny. Length of the three joints = 1:2:4, breadth =1:3:6. Cephalis
nearly spherical, with a very large, cylindrical, perpendicular, straight horn, once and a half to
twice as long as the whole shell. Thorax conical. Abdomen nearly hemispherical, with wide open
mouth. Pores circular, four to six times as broad in the thick-walled spiny abdomen as in the
thin-walled rough thorax.

Dimensions.- — Length of the three joints, a 0'03, b 0'06, c 012 ; breadth, a 0'03, b 0'09, c 018.

Habitat. — -Tropical Atlantic, Station 347, depth 2250 fathoms ; also fossil in Barbados.

(ZOOL. CHALL. BXP. — PART XL. — 1886.) Jfr 176

1402 THE VOYAGE OF H.M.S. CHALLENGER.

9. Theoeonus ampullaceus, HaeckeL

Lithocampe ampullacea, Ehrenberg, 1875, Abhandl, d. k. Akad. d. Wiss. Berlin, p. 66, Taf. iv.

fig. 1.
Theocorys ampullacea, Haeckel, 1881, Prodromus, p. 434.

Shell bell-shaped, nearly conical, thorny. Length of the three joints = 3 :4 : 10 ; breadth =
4:8:15. Cephalis subspherical, with a stout lateral horn of the same length. Thorax hemi-
spherical, rough. Abdomen subspherical, widely truncated at both poles, spiny. Pores regular,
circular, three to four times as broad in the thick-walled abdomen as in the thin-walled thorax.
(Differs from the similar preceding species in the smaller horn and the two deeper strictures of the
shell.)

Dimensions. — Length of the three joints, a 0'03, b O04, c 01 ; breadth, a 0'04, b 0'08, c 015.

Habitat. — Fossil in Barbados.

10. Theoeonus amplus, Haeckel.

1, Podocyriis ampla, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wisa. Berlin, p. 80, Taf. xvi. fig, 7.
1 Podocyrtis ampla, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 539, Taf. xxxiii. fig. 16.
'\Eucyrtidium arnplum, Ehrenberg, 1873, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 248.

Shell conical, smooth, with two broad internal annular septa. Length of the three joints =
1:3:4, breadth =1:4:5, Cephalis subspherical, with a very large, straight, conical horn of the same
breadth, which is as long as the conical thorax. Pores regular, circular, twice as broad in the
truncate, gradually dilated abdomen as in the thorax.

Dimensions. — Length of the three joints, a 0'03, b 0'09, c 012 ; breadth, a 0'03, b 012, e 015.

Habitat. — Fossil in Barbados.

1 1 . Theoeonus ariadnes, n. sp.

Shell conical, nearly bell-shaped, smooth. Length of the three joints = I ' 2 : 3, breadth = 1:3:5.
Cephalis subspherical, with a conical spine of about the same length. Thorax hemispherical, thiii-
walled. Abdomen conical, slightly constricted at the wide open mouth. Pores regular, circular,
twice as large in the thick-walled abdomen as in the thin-walled thorax.

Dimensions. — Length of the three joints, a 0-018 to 0'022, b 0'03 to 0'035, c O'OG to O'O1? ;
breadth, a Q'015 to 0'02, b 0'04 to 0'06, c 0'07 to 0'09.

Habitat. — Cosmopolitan ; Atlantic, Indian, and Pacific Oceans, common, surface.

12. Theoeonus dionysius, Haeckel.

Thyrsocyrtis dionysia, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii.

fig. 6.

Thyrsocyrtis jacchia, , Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii.
fig. 7.

Shell bell-shaped, smooth. Length of the three joints = 1:3:5, breadth = 1:4:5. Cephalis
subspherical, with a conical, irregularly denticulate horn of twice or thrice the length. Thorax

REPORT ON THE RADIOLARIA. 1403

inflated, nearly spherical, truncate at both poles, separated by a deep stricture from the cephalis, as
well as from the conical abdomen, which is dilated gradually towards the wide mouth. Pores in
the thorax subregular, circular, in the abdomen twice to four times larger, and irregular.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 01 ; breadth, a 0'02, b 0'08, c 01.

Habitat. — Fossil in Barbados.

13. Theoconus laterna, n. sp.

Shell conical, smooth. Length of the three joints = 1:2:4, breadth = 1:2:4. Cephalis
small, ovate, with a strong, pyramidal, vertical horn three times the length. Thorax hemispherical,
with subregular, circular, hexagonally-framed pores. Abdomen truncate, conical, with only fifteen
to twenty very large, irregular, polygonal pores, which are separated by very thick bars of the same
breadth as the horn.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 012 ; breadth, a 0'03, b 0'07, c 012.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

14. Theoconus ficus, Haeckel.

Eucyrtidimn ficus, Ehrenberg, 1875, Abhandl. d, k. Akad. d. Wiss. Berlin, p. 70, Taf. xi

fig. 19.
Theocorys ficus, Haeckel, 1881, Prodromus, p. 434.

Shell conical, pear-shaped, smooth. Length of the three joints = 1 : 5 : 20, breadth= 2 : 10 : 25.
Cephalis very small, ovate, with a conical, straight horn three tunes the length. Thorax quite
conical, with solid wall, without pores. Abdomen very large, nearly spherical, truncate at both
poles, little constricted at the very wide mouth ; its pores subregular, circular, about three times as
broad as the bars. (This species is intermediate between the genera Theoconus and Theocorys.)

Dimensions. — Length of the three joints, a O'Ol, b 0'05, c 0'2 ; breadth, a 0'02, b 01, c 0'25.

Habitat. — Fossil in Barbados.

Genus 614. Lophoconus,1 n. geru

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with conical abdomen
gradually dilated towards the wide open mouth. Cephalis with two or more horns or
a corona of horns.

The genus Lophoconus has the same conical shell with truncate mouth as Theoconvs,
and differs from it only in the armature of the cephalis, bearing either two large diver-
gent horns (usually a larger occipital and a smaller frontal horn), or a bunch or
corona of numerous divergent horns.

1 Lophoconus = Cone with a crest ; x«'<po?, xav

1404 THE VOYAGE OF H.M.S. CHALLENGER.

I. Lophoconus antilope, Haeckel.

Eucyrtidium antilope, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291, Taf. ix.
fig. 18.

Shell conical, smooth, with two slight strictures. Length of the three joints = 1:3:8, breadth
= 2:4: 8. Cephalis hemispherical, with two divergent, pyramidal horns of twice the length. Thorax
campanulate. Ahdomen gradually dilated towards the wide open mouth. Pores very small and
numerous, regular, hexagonal.

Dimensions. — Length of the three joints, a O'OIS, I 0'05, c 012 ; breadth, a O025, 5 0'07, c 012.

Habitat. — Indian Ocean ; between Aden and Socotra (Haeckel) ; Zanzibar (Pullen).

2. Lophoconus hexagonalis, n. sp.

Shell campanulate, conical, spiny, with two sharp strictures. Length of the three joints =
1 : 2:4, breadth = 1:3:6. Cephalis hemispherical, with numerous conical spines of different
sizes, the largest of twice the length. Thorax campanulate, with smaller spines. Abdomen inflated,
dilated towards the wide mouth. Pores large, three or four times as broad as the bars, subregular,
hexagonal.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'09 ; breadth, a 0'03, I 0'07, c 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Lophoconus cornutella, n. sp.

Shell slender, conical, smooth, without external strictures, but with two internal, annular septa.
Length of the three joints = 1:2:6, breadth = 1:2:4. Cephalis ovate, with two stout, divergent,
conical horns of three times the length. Thorax and abdomen together conical, gradually dilated
towards the wide truncate mouth. Pores regular, circular, quincuncial.

Dimensions. — Length of the three joints, a 0'03, 6 O'OS, c 012 ; breadth, a 0'02, 6 0'04, c O'OS.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

4. Lophoconus apiculatus., Haeckel.

Eucyrtidium apiculatum, Ehrenberg, 1875, AbhandL d. k. Akad. d. "VViss. Berlin, p. 70,
Taf. x. fig. 10.

Shell campanulate, conical, thorny, with two distinct strictures. Length of the three joints =
1:2:2, breadth = 1 : 3 : 4. Cephalis subspherical, with a bunch of eight to twelve divergent, conical
horns, the largest of which are longer than the cephalis. The regular, circular pores are in the
campanulate thorax scarcely half as broad as in the truncate, gradually dilated abdomen.

Dimensions. — Length of the three joints, a 0'02, 6 0'04, c 0'04 ; breadth," a 0'025, 6 0'06, c 0'08.

Habitat. — Fossil in Barbados.

EEPORT ON THE RADIOLARIA. 1405

5. Lophoconus cervus, Haeckel.

1 Eucyrtidium cervus, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291,
Taf. ix. fig. 21.

Shell conical, smooth, without external stricture, but with two internal annular septa. Length
of the three joints = 1:2:4, breadth = 1:3:6. Cepbalis campanulate, with two to six divergent,
partly ramified horns. Pores in the thorax regular, circular, in the abdomen three to four times
as large, regular, hexagonal.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'08 ; breadth, a 0'02, b 0'06, c 012.

Habitat. — Indian Ocean, Cocos Islands (Rabbe), surface (? Zanzibar, 2200 fathoms, Pullen).

6. Lophoconus rhinoceros, n. sp. (PI. 69, fig. 2).

Shell campanulate, conical, rough, with two sharp strictures. Length of the three joints =
1:2:3, breadth = 1:3:4. Cephalis subspherical, with numerous very small pores, and two stout,
divergent, pyramidal horns, the major of which is longer, the minor shorter, than the cephalis.
Thorax campanulate, with small, regular, circular pores. Abdomen inflated, with thickened margin
at the wide open mouth, and with irregular, roundish pores, twice to four times 'as broad as those
of the thorax.

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'09 ; breadth, a 0'04, b 0'09, c 012.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Genus 615. Theocyrtis,1 n. gen.

Definition. — Theocorida (vel Tricyrtida eradiata aperta) with cylindrical
abdomen, and wide open truncate mouth. Cephalis with a single horn.

The genus Theocyrtis and the three following closely allied genera differ from the
other Theocorida in the cylindrical form of the slender abdomen, which is of equal breadth
nearly throughout its whole length. The terminal mouth is wide open, usually truncate,
and of the same breadth ; sometimes slightly constricted. The cephalis of Theocyrtis
bears a single horn.

Subgenus 1. Theocorypha, Haeckel.

Definition. — Pores of the thorax and abdomen of nearly equal size and similar form.
1. Theocyrtis trachelius, Haeckel.

Eucyrtidium trachelius, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293, Taf.

vii. fig. 8.

Shell thin-walled and very fragile, smooth. Length of the three joints = 2:8:7, breadth =•
2:9:8. Cephalis subspherical, with a straight, conical horn of the same length, separated by a

1 Theocyrtis= Divine basket ; 6ios, xvari's.

1406 THE VOYAGE OF H.M.S. CHALLENGER.

slender neck from the inflated, subspherical thorax. Abdomen cylindrical, with a wide open,
truncate mouth. Pores subregular, hexagonal, of equal size, four to six times as broad as the
thin, thread-like bars.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'07 ; breadth, a 0'02, b 0'09, c 0'08.

Habitat. — Tropical Pacific, many Stations (200, 224, 271, &e.), surface, and in various depths.

2. Theocyrtis barbadensis, Haeckel.

Eucyrtidium barbadense, Ehienberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. ix. fig. 7.

Shell thin-walled, smooth. Length of the three joints = 2 :4:5, breadth, 2 : 5 : 4. Cephalis
ovate or conical, with a strong, conical horn, without external stricture, dilated into the campanulate
thorax. Abdomen cylindrical, with a wide open, truncate mouth. Pores subregular, circular,
quincuncially disposed, of about the same breadth as the bars.

Dimensions. — Length of the three joints, a 0'04, b 0'08, c 01 ; breadth, a 0'04, b 01, c 0-08.

Habitat. — Fossil in the Tertiary rocks of Barbados.

3. Theocyrtis cylindrica, HaeckeL

Eucyrtidium cylindricum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. x. fig. 1.

Shell elongate, cylindrical, straight, smooth. Length of the three joints = 1 : 2 : 6, breadth =
1:3:3. Cephalis hemispherical, with a thick, pyramidal horn of the same length (the edges of
the horn giving to it the appearance of being composed of two converging spines). Thorax truncated,
conical. Abdomen perfectly cylindrical, much elongated. Pores subregular, circular, twice as
broad as the bars, quincuncially disposed. Mouth wide open, truncate.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 012 ; breadth, a 0'03, b O'OG, c O'OG.

Habitat. — Tropical Pacific, Station 266, depth 2750 fathoms ; fossil in Barbados.

4. TJieocyrtis elegans, Haeckel.

Eucyrtidium elegans, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi. fig. 12.
1 Eucyrtidium pusillurn, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72,
Taf. xi. fig. 6.

Shell slender, cylindrical, straight, smooth. Length of the three joints =1:2:7, breadth =
1:3:3. Cephalis subconical, with a small conical horn. Thorax campanulate, conical.
Abdomen cylindrical, very slender. Pores subregular, circular, small, disposed in transverse rows,
three in the thorax, six to eight in the abdomen. Mouth wide open, truncate.

Dimensions. — Length of the three joints, a O'Ol, b 0'02, c 0'07 ; breadth, a 0'015, b 0'03, c 0'03.

Habitat. — Fossil in Barbados and Sicily.

REPORT ON THE RADIOLARIA, 1407

5. Theocyrtis paupera, Haeckel.

Eucyrtidium pauperum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi.
fig. 13.

Shell slender, cylindrical, smooth. Length of the three joints = 1:2:6, breadth = 1:3:3.
Cephalis hemispherical, with a stout conical horn of twice the length. Thorax truncate, conical
Abdomen cylindrical. Pores very small, regular, circular, disposed in transverse rows, one or two
in the thorax, three to five in the abdomen. (Distance between the rows twice as great as in the
preceding nearly related species.) Mouth wide open, truncate.

Dimensions. — Length of the three joints, a O'Ol, b 002, c O06 ; breadth, a 0'015, b 0'03,

c 0-03.

Habitat. — Western Tropical Pacific, Station 225, depth 44*75 fathoms ; also fossil in Barbados

and Sicily.

6. Theocyrtis microtheca, Haeckel.

Eucyrtidium microtheca, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi.

fig. 10.
Eucyrtidium hillaby, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi.

fig. 8.

Shell cylindrical, a little rough. Length of the three joints = 1:3:4, breadth = 1:3:3.
Cephalis subspherical, with a small conical horn. Thorax hemispherical or campanulate. Abdomen
cylindrical, with wide open truncate mouth. Pores subregular, circular, quincuncially disposed, of
medium size, rudimentary or wanting in the cephalis.

Dimensions. — Length of the three joints, a 0'015 to 0'02, b 0'03 to 0'05, c 0'05 to 0'08 ; breadth,
a, 0'02 to 0-025, b 0'05 to O'OG, c O'Oo to 0'06.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms; also fossil in Barbados.

Subgenus 2. Theocorusca, Haeckel.
Definition. — Pores of the thorax and the abdomen of different sizes or forms.

7. Theocyrtis macroceros, n. sp. (PL 69, fig. 13).

Shell almost cylindrical, smooth. Length of the three joints =1:2:5, breadth = 2:3:4.
Cephalis hemispherical, with a very large cylindrical horn, once or twice as long as the shell.
Thorax truncate, hemispherical. Abdomen cylindrical, only slightly contracted towards both ends.
Two girdle strictures deep. Pores small, subregular, circular, more irregular and twice to three times
as large in the abdomen as in the thorax, disposed in transverse rows, five to six in the thorax,
eight to ten in the abdomen.

Dimensions. — Length of the three joints, a 0'02 to 0'03, b 0'04 to 0-05, c 01 to 012 ; breadth,
a, 0-04, b 0-07, c 0'08.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms ; also fossil in Barbados.

1408 THE VOYAGE OF H.M.S. CHALLENGEK.

8. Theocyrtis ptychodes, n. sp. (PI. 69, fig. 8).

Shell almost cylindrical, smooth. Length of the three joints =1:3:3, breadth — 2:4:4.
Cephalis hemispherical, with a large, conical, curved horn of twice the length. Thorax very large,
inflated, campanulate, thick-walled. Abdomen cylindrical, with a thin folded wall (like a petticoat),
the thickness of which decreases gradually towards the wide truncate mouth. Pores subregular,
circular, and quincuncially disposed in the two first joints, irregular arid larger in the abdomen,
forming longitudinal series between the folds.

Dimensions. — Length of the three joints, a 0'04, & 01, c Oil ; breadth, a 0-05, I 012, c 012.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

9. Theocyrtis aspera, Haeckel.

Eucyrtidium asperwn, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. viii.
fig. 15.

Shell almost cylindrical, with rough or thorny surface. Length of the three joints = 1:3:5,
breadth = 1:5:5. Cephalis subspherical, small, with a short conical horn. Thorax hemispherical,
inflated. Abdomen cylindrical, with wide truncate mouth. Pores in the thorax subregular, circular,
quincuncially disposed, in the abdomen irregular roundish, two to four times as large.

Dimensions. — Length of the three joints, a 0'015 to 0'02, b 0'06 to 0'07, c 0'08 to 01 ; breadth,
a 0-02, b 01, c 01.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms ; fossil in Barbados.

10. Theocyrtis proserpince, n. sp.

Shell almost cylindrical, smooth. Length of the three joints = 3:6:9, breadth = 2:8:7.
Cephalis subspherical, with a stout conical horn. Thorax campanulate. Abdomen cylindrical.
Pores regular, circular, quincuncially disposed, double-edged in the thorax, and three to four times
as large as in the cephalis and the abdomen.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 0'09 ; breadth, a 0'02, b 0'08, c 0'07.

Habitat. — North Pacific, Stations 244 to 253, depth 2050 to 3125 fathoms.

11. Theocyrtis oenophila, Haeckel.

Tlryrsocyrtis oenopliila, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii.
fig. 8.

Shell in the apical half conical, in the lower cylindrical. Length of the three joints = 2:5:6,
breadth = 3:8:7. Cephalis subspherical, with a large prismatic horn, which is bulbous at the
base, and armed with three teeth at the distal apex. Thorax conical, constricted at the base,
with subregular, circular, quincuncial pores. Abdomen cylindrical, with a coronal of nine large

REPORT ON THE RADIOLARIA. 1409

roundish pores beyond the lumbar stricture, and two to four succeeding transverse rows of irregular,
roundish, smaller pores. Mouth widely open, truncated.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'06 ; breadth, a 0'03, b 0'08, c 0'07.

Habitat. — Fossil in Barbados.

Genus 616. Theosyringium, Haeckel,1 1881, Prodromus, p. 434.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with cylindrical
abdomen, which is much narrower than the inflated thorax, and forms a slender, narrow
tube, with truncated mouth. Cephalis with a single horn.

The genus Theosyringium differs from the closely allied Theocyrtis, its ancestral
form, in the wide inflated thorax, which is much broader than the narrow tubular
abdomen. The mouth of the latter is small and truncate.

1. Theosyringium tibia, n. sp. (PI. 68, fig. 4).

Shell rough, very slender, with two distinct strictures. Length of the three joints = 1 : 3:4,
breadth = 1:2:1. Cephalis ovate, with a conical horn of the same length. Thorax ellipsoidal.
Abdomen cylindrical, as long as the two former joints together. Pores subregular, circular.

Dimensions. — Length of the three joints, a 0'03, b O09, c 012 ; breadth, a 0'03, b 0'06, c 0'02.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

2. Theosyringium pipetta n. sp. (PI. 68, fig. 5).

Shell rough, inflated, with two sharp strictures. Length of the three joints = 2 : 7:9, breadth =
2:7:2. Cephalis conical, with a slender horn of half the length. Thorax subglobose. Abdomen
cylindrical, as long as the two former joints together. Pores subregular, circular.

Dimensions. — Length of the three joints, a 0'02, b 0'07, c 0'09 ; breadth, a 0'02, b 0'07, c 0'02.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Theosyringium siphonium, n. sp.

Shell rough, inflated, with two deep strictures. Length of the three joints = 1:3:3, breadth =
1:2:1. Cephalis subspherical, with a stout pyramidal horn of twice the length. Thorax broad
ovate. Abdomen slender, inversely conical, as long as the thorax, and one-third as broad as
the base. Pores subregular, circular, hexagonally framed. (Similar to Husyringium conosiphon,
PI. 78, fig. 10) but only with two strictures and three joints.)

Dimensions. — Length of the three joints, a 0'03, b 01, c 01 ; breadth, a 0'03, b 0'07, c 0'025.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

1 Theosyringium— Divine tube; 610;, ev^ly/ion.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 177

1410 THE VOYAGE OF H.M.S. CHALLENGER.

4. Theosyringium tubulus, Haeckel.

Eucyrtidium tubulus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72,
Taf. xi. fig. 6.

Shell smooth, slenderly spindle-shaped, with two slight strictures. Length of the three joints =
2:10:8, breadth = 3 : 6 : 3. Cephalis hemispherical, hyaline, with a stout, pyramidal horn of
the same length. Thorax spindle-shaped. Abdomen inversely conical, half as long as the thorax
prolonged into a slender, cylindrical tube. Pores subregular, circular.

Dimensions. — Length of the three joints, a, 0'02, b 01, c Q'08 ; breadth, a 0'03, 1 0'06, c 0'03.

Habitat. — Fossil in Barbados.

Genus 617. Lophocyrtis,1 n. gen.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with cylindrical
abdomen, and wide open truncate mouth. Cephalis with two horns, or a bunch of
horns.

The genus Lophocyrtis differs from its ancestral form Theocyrtis only in the
armature of the cephalis, bearing instead of a single horn either two divergent
horns, or a bunch, or coronal of numerous spines. The slender abdomen is in both
genera cylindrical, with wide open mouth.

1. Lophocyrtis holothuria, n. sp.

Shell smooth, slender, with two distinct strictures. Length of the three joints = 1:2:4,
breadth = 2:4:3. Cephalis hemispherical, with a bunch of five divergent, conical horns, the
middle of which is larger and vertical, nearly as long as the thorax. Thorax campanulate, half as
long as the cylindrical abdomen. Mouth truncate. Pores regular, circular, quincuncial. (Similar
to Theocyrtis cylindrica, but with different cephalis and thorax.)

Dimensions. — Length of the three joints, a O'OS, b OD5, c 01 ; breadth, a 0'04, b 0'07, c 0'06.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Lophocyrtis stephanophora, Haeckel.

Eucyrtidium stephanophorum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72,
Taf. viii. fig. 14.

Shell smooth, slender, with deep collar and indistinct lumbar stricture. Length of the three
joints = 1:2:4, breadth = 1:3:3. Cephalis subspherical, with very small circular pores, and a
corona of three to nine short conical spines. Thorax campanulate, with regular, circular pores,
which are half or one-third as broad as those of the cylindrical abdomen.

Dimensions. — Length of the three joints, a 0-025, b 0'05, c 0'09 ; breadth, a 0'025, b 0'06, c 0'06.

Habitat. — Fossil in Barbados.

1 Lophocyrtis =Za,sket \rith a crest ;

REPORT ON THE RADIOLARIA. 1411

3. Lophocyrtis synapta, n. sp.

Shell spiny, with two sharp strictures. Length of the three joints = 5 : 10 : 6, breadth =
4:9:7. Cephalis large, ovate, with numerous (twenty to thirty or more) conical, radially
divergent spines of different sizes, the largest about as long as the cephalis. Thorax subconical,
with numerous short, conical, divergent spines, which are directed downwards. Abdomen smooth,
cylindrical. The irregular, polygonal pores are separated by thin bars, and in the thorax are twice
to four times as broad as in the first and last joints.

Dimensions. — Length of the three joints, a 0'05, b 01, c 0'06 ; breadth, a 0'04, b 0'09, c 0'07.

Habitat. — Indian Ocean, Maldive Islands (Haeckel), surface.

4. Lophocyrtis coronata, Haeckel.

Eucyrtidium coronation, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. x. fig. 9.

Shell smooth, cylindrical, with two deep strictures. Length of the three joints = 4:3:4,
breadth = 4:5:4. Cephalis subspherical, large, of about the same size and form as the thorax,
with a coronal of four to eight short, conical spines on the apex. Pores in the two first joints
irregular, roundish, twice to four times as broad as the small, circular pores of the cylindrical
abdomen, which are disposed in four to eight transverse rows.

Dimensions. — Length of the three joints, a 0'04, I 0'03, c 0'04 ; breadth, a 0'04, b 0'05, c 0'04.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms ; fossil in Barbados.

5. Lophocyrtis biaurita, Haeckel.

Eucyrtidium liauritum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,

Taf. x. fig. 8.
Eucyrtidium Nauritum, Biitschli, 1882, Zeitschr. f. wiss. Zool., p. 540, Taf. xxxiii. fig. 38, a-f.

Shell smooth, with two distinct strictures. Length of the three joints = 1:6:3, breadth =
2:5:4. Cephalis small, hemispherical, hyaline, with two large, divergent, curved horns of three
times the length. Thorax ovate, with few small, widely scattered pores. Abdomen cylindrical,
without pores.

Dimensions. — Length of the three joints, a 0'015, b 0'06, c 0'03 ; breadth, a 0'02, b 0'05, c 0'04.

Habitat. — Fossil in P>arbados.

Genus 618. Tricolocampe,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — T heocorida (vel Tricyrtida eradiata aperta), with cylindrical
abdomen, and wide open truncate mouth. Cephalis without horn.

The genus Tricolocampe differs from its ancestral genus, Theocyrtis, in the loss of
the cephalic horn ; it has the same cylindrical form of the slender abdomen, and a wide

1 Tricolocampe = Caterpillar with three joints ; T^I'S, x.ahov,

1412 THE VOYAGE OF H.M.S. CHALLENGER.

open terminal mouth of the same breadth. The whole shell is more or less cylindrical,
(sometimes conical in the upper part), with two distinct external strictures, or internal
annular septa.

Subgenus 1. Tricolocampium, Haeckel.

Definition. — Pores of the thorax and of the abdomen of nearly equal size and
similar form.

1. Tricolocampe cylindrica, n. sp. (PL 66, fig. 21).

Shell nearly cylindrical, smooth. Length of the three joints = 2 : 3 : 15, breadth = 3:4:5.
Cephalis hemispherical, with numerous very small pores. Thorax and abdomen cylindrical, of
about equal breadth, with equal, circular pores, disposed regularly in transverse rows, three to four
rows in the thorax, ten to twelve in the abdomen. Mouth wide open, not constricted.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c O'l 5 ; breadth, a 0'03, b 0'04, c 0'05.

Habitat. — Central Pacific, Stations 265 to 274, depth 2350 to 2925 fathoms.

2. Tricolocampe pupa, Haeckel.

Eucyrtidium pupa, Ehrenberg, 1872, AbliandL d. k. Akad. d. Wiss. Berlin, p. 293,
Taf. vii. fig. 16.

Shell nearly cylindrical, smooth. Length of the three joints =. 2 : 2 : 8, breadth = 2 : 3 : 3.
Cephalis subspherical, with four larger pores. Thorax, and abdomen cylindrical, of about equal
breadth, with equal, very small pores, disposed regularly in transverse rows, two rows in the
thorax, eight to ten in the abdomen. Mouth wide open, a little constricted.

Dimensions. — Length of the three joints, a 0'02, 6 O02, c 0'08 ; breadth, a 0'02, b 0'03, c 0'03.

Habitat. — Tropical Pacific (Philippine Sea), Station 206, depth 2100 fathoms.

3. Tricolocampe poly zona, n. sp. (PL 66, fig. 19).

Shell nearly cylindrical, thick-walled. Length of the three joints = 4:4: 12, breadth = 8:9:9.
Cephalis obtuse, conical. Thorax barrel-shaped. Abdomen in the middle part a little constricted.
Pores very numerous, subregular, disposed regularly in transverse rows, six to eight in the cephalis,
eight to ten in the thorax, twelve to fifteen in the abdomen. Mouth rather constricted, only half
as broad as the abdomen.

Dimensions. — Length of the three joints, a 0'04, b 0'04, c 012 ; breadth, a 0'08, b 0'09, c 0'09.

Habitat. — Central Pacific, Stations 266 to 272, depth 2425 to 2925 fathoms; also fossil in the
Nicobars and in Barbados.

EEPORT ON THE RADIOLARIA. 1413

4. Tricolocampe stenozona, n. sp. (PI. 66, fig. 20).

Shell nearly cylindrical, thin- walled. Length of the three joints = 5:4:9, breadth = 6:8:9.
Form of the three joints and disposition of their pores nearly equal to the preceding species ; but
the proportion of the joints is different, the shell more delicate, and the mouth more widely open, and
nearly as broad as the abdomen.

Dimensions. — Length of the three joints, a 0'05, I 0'04, c 0'09 ; breadth, a 0'06, I 0'08, c 0'09.

Habitat. — North Pacific, Station 256, depth 2950 fathoms.

5. Tricolocampe amphizona, n. sp. (PI. 66, fig. 17).

Shell mitre-shaped, very thick-walled. Length of the three joints =2:1:1, breadth nearly
uniform. Cephalis obtuse, conical, as long as the two other cylindrical joints together (probably
composed of several united joints). Pores subregular, disposed in transverse rows, six to eight in
the cephalis, two in the .thorax, and two in the abdomen. Mouth widely open.

Dimensions. — Length of the three joints, a 0'04, b 0'02, c 0'02 ; breadth, a 0'04, b 0'05, c 0'05.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

6. Tricolocampe panthera, Haeekel.

Eueyrtidium panthera, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi.
fig. 18.

Shell mitre-shaped or nearly cylindrical, thick-walled. Length of the three joints = 1:2:3,
breadth = 1 : 2 : 2. Cephalis subspherical. Thorax campanulate. Abdomen cylindrical. Pores in
all three joints irregular, roundish, of different sizes, irregularly disposed. Mouth widely open,
truncated, not constricted.

Dimensions. — Length of the three joints, a 0'015 to 0'02, b 0'04 to 0'05, c 0'06 to 0'08 ; breadth
about a 0'02, b and c 0'05.

Habitat. — Cosmopolitan ; Atlantic, Pacific ; also fossil in Barbados.

Subgenus 2. Tricolocamptra, Haeekel.
Definition. — Pores of the thorax and the abdomen of different sizes or forms.

7. Tricolocampe urnula, n. sp. (PL 66, fig. 22).

Shell cylindrical, with obtuse conical apex, smooth. Length of the three joints = 2:3:10, breadth
= 2:3:6. Cephalis subspherical. Thorax barrel- shaped. Abdomen cylindrical with slightly, con-
stricted wide mouth. Pores irregular, roundish, three to four times as broad in the abdomen
as in the thorax, irregularly disposed.

Dimensions. Length of the three joints, a 0'02, b 0'03, c O'l ; breadth, a 0'025, b 0'035, c 0'06.

Habitat. Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

1414 THE VOYAGE OF H.M.S. CHALLENGER.

8. Tricolocampe doliolum, n. sp.

Shell cylindrical, with hemispherical apex, rough. Length of the three joints = 1:3:5, breadth
= 1:2:3. Cephalis spherical. Thorax and abdomen cylindrical, of nearly equal breadth. Mouth
widely open, not constricted. Pores irregular, roundish, in the abdomen three to four times as
large as in the thorax, disposed in oblique rows.

Dimensions. — Length of the three joints, a 0'03, b 0'09, c 0-16 ; breadth, a 0'03, b 0'05, c 0'09.

Habitat. — Fossil in Barbados.

9. Tricolocampe cingulata, n. sp.

Shell subcylindrical, with obtuse conical apex, thick-walled. Length of the three joints =
2 : 3 : 11, breadth = 3:7:8. Cephalis hemispherical, not separated externally from the short conical
thorax, but with internal collar septum. Abdomen cylindrical, with wide open, non-constricted
mouth. Pores in the thorax narrow, obliquely ascending, in the abdomen twice as large, circular,
arranged in ten to twelve regular transverse rows, separated by slight strictures. Lumbar septum
nearly complete.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 01 to 012; breadth, a 0'03, b 0'07,
c 0-08.

Habitat. — Fossil in Barbados, and in Tertiary rocks of Sicily ; living in the depths of the Atlantic
and Central Pacific, Station 348, depth 2450 fathoms ; Station 268, depth 2900 fathoms.

10. Tricolocampe arcta, Haeckel.

? Eucyrtidium arctum, Ehrenberg, 1858, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 33.
1 Lithocampe arcta, Haeckel, 1862, Monogr. d. Radiol., p. 317.

Shell subcylindrical, with obtuse conical apex. Length of the three joints =1:2:4, breadth =
1:2:2. Cephalis subspherical. Thorax campanulate, separated by a deep collar, but a slight
lumbar stricture. Abdomen cylindrical, with wide truncate mouth. Pores in the thorax narrow,
obliquely ascending, in the abdomen half as large, very small, and densely disposed in six to eight
regular transverse rows.

Dimensions. — Length of the three joints, a 0'022, I 0'045, c 0'09 ; breadth, a 0'026, b 0405, c 0'05.

Habitat. — Central Pacific, Station 266 to 274, depth 2350 to 2925 fathoms.

Genus 619. Theocorys,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with ovate abdomen,
broader than the constricted mouth. Cephalis with a single horn.

The genus TJieocorys and the two following closely allied genera, united formerly
with Eucyrtidium, differ from the preceding Theocorida in the constriction of the

1 17ieocor2/s=Divine helmet ; hoi,

REPORT ON THE RADIOLARIA. 1415

peristome, so that the inflated abdomen is broader than the terminal mouth. They
represent, therefore, the transition to the Theocapsida, with closed mouth. The
abdomen is commonly more or less ovate or barrel-shaped, sometimes inversely conical.
The cephalis of Theocorys bears a single apical horn,

Subgenus 1. Theocoronium, Haeckel.

Definition. — Pores of the thorax and of the abdomen of nearly equal size and
similar form.

1. Theocorys turgidula, Haeckel.

Eucyrtidium turgidulum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293, Taf. vii.
fig. 13.

Shell slender, ovate, with two deep strictures, very fragile and thin-walled. Length of the
three joints = 2:5:7, breadth = 2:6:6. Cephalis subspherical, with a pyramidal horn of the same
length. Thorax nearly spherical. Abdomen ovate, twice as broad as the constricted mouth.
Pores very numerous, regular hexagonal, three to four times as broad as the bars.

Dimensions. — Length of the three joints, a 0'015, b 0'005, c 0'07 ; breadth, a 0'02, b 0'06,
c 0-06.

Habitat. — Tropical Pacific (Philippine Sea), Stations 206 and 224, surface.

2. Theocorys veneris, n. sp. (PL 69, fig. 5).

Shell inversely ovate, with two deep strictures, smooth. Length of the three joints = 2:5:6,
breadth = 3:7:6. Cephalis hemispherical, with a slender conical horn of twice the length.
Thorax nearly spherical. Abdomen ovate, twice as broad as the constricted mouth. Pores regular,
circular, twice as broad as the bars, quincuncially disposed.

Dimensions. — Length of the three joints, a 0'02, b G"05, c 0'06 ; breadth, a 0'03, b 0'07, c 0'06.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific ; many Stations, surface.

3. Theocorys cretica, Haeckel.

Eucyrtidium cretieum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291, Taf. xi.
fig. 23.

Shell ovate, thin-walled, smooth, with two deep strictures. Length of the three joints =
2:4:4, breadth = 3 : 6 : 6. Cephalis hemispherical, with a conical horn of the same length.
Thorax and abdomen nearly hemispherical, inflated, united by the opposite bases of the hemispheres.
Constricted mouth only one-third as broad as the abdomen. Pores very small and numerous,
regular, circular, of the same breadth as the bars, quincuncially disposed.

Dimensions. — Length of the three joints, a O2, b 004, c 0'04 ; breadth, a 0'03, b 0'06, c 0'06.

Habitat. — Mediterranean, Crete, Corfu, surface.

1416 THE VOYAGE OF H.M.S. CHALLENGER.

4. Theocorys ovata, n. sp. (PL 69, fig. 16).

Shell quite ovate, thick-walled, smooth, without external strictures. Length of the three joints
= 2:2:9, breadth = 3:5:7. Cephalis conical, with a thick conical horn of the same length.
Thorax and abdomen gradually dilated towards the base, and then hemispherical, constricted.
Mouth scarcely one-third as broad as the abdomen, prolonged into a short tube. Pores regular,
circular, disposed in transverse rows, two to three in the cephalis, two to three in the thorax, eight
to ten in the abdomen.

»

Dimensions. — Length of the three joints, a 0'02, b 002, c 0'09 ; breadth, a O03, b 0'05, c 0'07.
Habitat. — Central Pacific, Stations 263 to 268, depth 2650 to 3000 fathoms.

5. Theocorys plutonis, n. sp. (PL 69, fig. 1).

Shell ovate, thick-walled, smooth, with two slight strictures. Length of the three joints =
2:5:4, breadth =4:7:6. Cephalis hemispherical, with a conical, oblique horn of the same
length. Thorax and abdomen only slightly inflated, gradually decreasing towards the wide, little
constricted mouth. Pores subregular, circular, much larger in the abdomen and the lower half of
the thorax than in the upper half and the cephalis.

Dimensions. — Length of the three joints, a OD2, b 0'05, c 0'04 ; breadth, a 0'04, b 0'07, c 0'06.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

6. Theocorys scolopax, Haeckel.

Eucyrtidium scolopax, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wise. Berlin, p. 72,
Taf. is. fig. 5.

Shell slender, inversely ovate, smooth. Length of the three joints = 1:3:3, breadth = 1:4:4.
Cephalis subspherical, with a long, slightly curved horn, half as long as the whole shell. Thorax
campanulate. Abdomen inversely ovate, twice as broad as the constricted mouth (incomplete in
Ehrenberg's figure).

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'06 ; breadth, a 0'02, b 0'08, c 0'08.

Habitat. — Fossil in Barbados.

Subgenus 2. Theocorythium, Haeckel.

Definition. — Pores of the thorax arid of the abdomen of different sizes or dissimilar
forms.

7. Theocorys diance, n. sp. (PL 69, fig. 11).

Shell almost ovate, with two deep strictures. Length of the three joints =3:6:8, breadth =
3:9:8. Cephalis subspherical, with a slender, pyramidal horn of three times the length. Thorax

REPORT ON THE RADIOLARIA. 1417

conical, constricted at the base. Abdomen bottle-shaped. Pores in the thorax irregular,
polygonal, in the abdomen subregular, circular, quincuncially disposed.

Dimensions. — Length of the three joints, a 0'03, 6 0'06, c 0'08 ; breadth, a 0'03, b 0'09, c 0'08.

Habitat. — North Pacific, Station 253, surface.

8. Theocorys hyaloihorax, n. sp.

Shell slender, ovate, with two deep strictures. Length of the three joints = 6:9:8, breadth =
7 : 12 : 11. Cephalis subspherical, with numerous densely-placed circular pores, and with a
pyramidal, slender horn of the same length. Thorax hemispherical, hyaline, without any pores.
Abdomen ovate, twice as broad as the constricted mouth, with two to four widely distant,
transverse rows of small, circular pores.

Dimensions. — Length of the three joints, a 0'024, I 0-036, c 0'032 ; breadth, a 0'028, b 0'048,
c 0-044.

Habitat. — Tropical Pacific, Station 225, depth 4475 fathoms.

9. Theocorys bachabunda, Haeckel.

Thyrsoeyrtis bacliabunda, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84
Taf. xii. fig. 4.

Shell inversely ovate, with two distinct strictures. Length of the three joints = 2:5:9,
breadth = 3:9:8. Cephalis subspherical, small, with a large cylindrical horn, which is half as
long as the whole shell, and armed with spines at the conical apex. Thorax conical, inflated, with
small, subregular, circular, quincuncial pores. Abdomen inversely ovate, with irregular, roundish,
pores of larger and smaller sizes mixed, gradually lessening towards the constricted mouth.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'09 ; breadth, a 0'03, b 0'09, c 0'08.

Habitat. — Fossil in Barbados.

10. Theocorys attenuata, Haeckel.

Eucyrtidium attenuatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. xi. fig. 16.

Shell inversely ovate, with distinct collar, but indistinct lumbar stricture. Length of the
three joints = 2:5:5, breadth = 2:7:6. Cephalis hemispherical, with a short, oblique, conical
horn. Thorax inflated, campanulate, with small, regular, circular, quincuncial pores. Abdomen
inversely conical, with irregular pores of larger and smaller sizes mixed, gradually lessening towards
the truncated mouth.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'05 ; a 0'025, b 0'07, c 0'06.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

11. Theocorys obliqua, n. sp. (PI. 69, fig. 10).

Shell inversely ovate, with distinct collar, but indistinct lumbar stricture. Length of the
three joints = 3:7:4, breadth = 4:9:8. Cephalis hemispherical, with a stout, pyramidal, oblique

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 178

1418 THE VOYAGE OF H.M.S. CHALLENGER.

horn of the same length. Thorax and abdomen together ovate, gradually lessening towards the
constricted mouth, which is only half as broad. Pores irregular, roundish, in the thorax twice to
four times as broad as in the abdomen. Both joints are separated by an oblique, internal, lumbar
septum, which in some specimens observed was more oblique than in that figured; some specimens
had a very irregular form.

Dimensions. — Length of the three joints, a 0'025 to 0'03, 1 0'06 to 0'07, c 0'03 to O04 ; breadth,
a 0-04, b 0'09, c 0'08.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms ; also fossil in Barbados.

12. Theocorys alauda, Haeckel.

Eucyrtidium alauda, Ehrenberg, 1875, Adhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. ix. fig. 4.

Shell nearly spindle-shaped, decreasing from the thicker middle towards both ends. Length of
the three joints = 1:3:8, breadth = 1:4:5. Cephalis subspherical, with a strong, conical horn
of three times the length. Thorax campanulate, with numerous regular, circular, quincuncial
pores. Abdomen inversely ovate, slender, twice as broad as the truncated mouth, with irregular,
roundish pores, three to four times as large as those of the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 016 ; breadth, a 0'03, b 0'08, c 01.

Habitat. — Fossil in Barbados and in Tertiary rocks of Sicily.

13. Theocorys apollinis, n. sp. (PL 69, figs. 3).

Shell ovate, with two deep strictures. Length of the three joints = 2 : 3 : 5, breadth = 2 : 5 : 7.
Cephalis subspherical, with a large, straight, cylindrical horn, about as long as the whole shell (in
the specimen figured this is broken off). Thorax truncate, conical. Abdomen subglobose, truncate
on both poles, twice as broad as the constricted mouth. Pores quincuncial, subregular, circular,
twice as broad in the abdomen as in the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c O'Oo ; breadth, a 0'02, b 0'05, c 0'07.

Habitat. — South Atlantic, Station 332, surface.

14. Theocorys sphcerophila, Haeckel.

Eucyrtidium splicer ophilum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72,
Taf. viii. fig. 16.

Shell almost ovate, rough, with two slight strictures. Length of the three joints = 2 : 7: 10,
breadth = 3 : 8 : 12. Cephalis subspherical, with a strong, conical horn of the same length. Thorax
nearly spherical, with subregular, circular pores of different sizes. Abdomen ovate, truncate at
both poles, nearly twice as broad as the constricted mouth, with very large, subregular, hexagonal
pores, four to six times as broad as the bars, in three to four transverse, and ten to twelve longi-
tudinal rows.

Dimensions. — Length of the three joints, a 0'02, b 0'07, c 01 ; breadth, a 0'03, b 0'08, c 012.

Habitat. — Central Pacific, Station 26C, depth 2750 fathoms ; fossil in Barbados.

REPORT ON THE RADIOLARIA. 1419

15. Theocorys tuberculata, n. sp.

Shell almost ovate, tuberculate, with deep collar, but slight lumbar stricture. Length of the
three joints =2 : 5 : 12, breadth = 3: 8 : 11. Cephalis hemispherical, with a cylindrical horn of
twice the length. Thorax hemispherical, with regular, circular, double-edged, quincuncial pores,
between which conical tubercles occur. Abdomen truncate, ovate, twice as broad as the constricted
mouth, with regular, circular, hexagonally-framed pores, three to four times as broad as those of
the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 012 ; breadth, 0'03, b O08, c Oil.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms ; fossil in Barbados.

16. Theocorys martis, n. sp.

Shell slender, ovate, with two deep strictures. Length of the three joints = 3 : 6 : 18, breadth
= 4:8:12. Cephalis small, hemispherical, with a very large, sword-shaped broad horn, nearly as
long as the whole shell. Thorax hemispherical, honey-comb like, with regular, circular, hexagon-
ally-framed pores. Abdomen ovate, with irregular, roundish, very large pores, four to six times as
broad as the bars, and as the pores of the thorax. Constricted mouth half as broad as the
abdomen.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 018 ; breadth, a 0'04, b 0'08, c 012.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

17. Theocorys mercurii, n. sp.

Shell ovate, conical, with two slight strictures. Length of the three joints = 1:3:7, breadth
= 2:4:7. Cephalis hemispherical, with a broad pyramidal horn of the same length. Thorax
campanulate, with longitudinal series of small, regular, circular pores, separated by divergent crests.
Abdomen nearly spherical, one and a half times as broad as the( constricted mouth, which is pro-
longed into a thin, solid, cylindrical peristome. Pores of the abdomen regular, circular, hexa-
gonally framed, three to four times as broad as the bars, and as the pores of the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 015 ; breadth, a 0-04, b 0'09, c 015.

Habitat. — South Atlantic, Station 338, depth 1990 fathoms.

18. Theocorys minervce, n. sp. (PI. 69, fig. 14).

Shell ovate, conical, with two deep strictures. Length of the three joints = 1:3:4, breadth =
1:4:5. Cephalis subspherical, with a large pyramidal horn as long as the thorax, and with
small, circular pores. Thorax rough, with regular, quincuncial, circular pores, three to four times
as large as those of the cephalis. Abdomen barrel-shaped, with irregular, roundish pores of very
different sizes, six very large pores immediately beyond the lumbar stricture, and four to five rows

&

1420 THE VOYAGE OF H.M.S. CHALLENGER.

of pores, which are twice to four times as large as those of the thorax. Mouth truncated, with
thickened margin, two-thirds as broad as the abdomen.

Dimensions. — Length of the three joints, a 0'04, 6 012, c 016; breadth, a 0'04, & 016, c 0'2.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 620. Axocorys,1 Haeckel, 1881, Prodromus, p. 434.

Definition. — Theocorida (vel Tricyrtida eradiata aperta), with ovate abdomen,
including an internal vertical axial rod, which bears three divergent radial spines or
verticils of three branches, and is prolonged into an apical horn.

The genus Axocorys contains only a single but very remarkable species, and may,
perhaps, represent a peculiar group, which has closer relations to the Plectoidea than
to the other Tricyrtida. The pyriform three-jointed shell has neither lateral nor
terminal free appendages, but possesses a very large apical horn, and an inner pro-
longation of this, an axial rod, which bears some triradiate verticils of branched spines.
The original ancestral forms of this remarkable genus are probably Plagoniscus and
Plectaniscus (pp. 912 and 924).

1. Axocorys macroceros, n. sp. (PI. 68, figs. 1, la).

Shell pear-shaped, with two distinct strictures. Length of the three joints = 2 : 3 : 16, breadth
= 3:6:16. Cephalis hemispherical, with few small pores. From its apex arises vertically a
very long three-sided prismatic horn with denticulate edges, three to four times as long as the
shell. An inner thin prolongation of the horn descends vertically nearly to the mouth, and bears
on its basal end three verticils of branched spines, each verticil with three divergent forked spines
(fig. la). Pores regular, circular, in the subspherical abdomen three times as large as in the hemi-
spherical thorax. The constricted mouth is scarcely broader than the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 016 ; breadth a 0'03, 6 0'06, c 016.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 621. Lophocorys,2 Haeckel, 1881, Prodromus, p. 434.

Definition. — T he'ocorida (vel Tricyrtida eradiata aperta), with ovate abdomen,
broader than the constricted mouth. Cephalis with two divergent horns, or with a
bunch of horns.

1 .4zocon/s = Holniet with an internal axis; «!<e, xfyvs.

2 Lophocorys = Helmet with a top crest ; *o<pof, KO^VS-

REPORT ON THE RADIOLARIA. 1421

The genus Lophocorys differs from its ancestral form, Theocorys, only in the
armature of the cephalis, bearing either two divergent horns, or a corona of several
radial horns. In two , species there are four horns on the apex, a larger vertical
(occipital) horn being surrounded by three smaller, upwards divergent horns.

1. Lophocorys astrocephala, n. sp. (PI. 69, fig. 9).

Shell smooth, inversely ovate, with deep collar and slight lumbar stricture. Length of the
three joints = 3 : 7 : 6, breadth =4 : 11 : 10. Cephalis subspherical, stellate, densely covered with
numerous (ten to twenty or more) divergent, large, slenderly conical horns, the longest of which reach
the length of the shell. Thorax campanulate, with small, regular, circular pores. Abdomen taper-
ing towards the constricted mouth, in the upper half with the same pores, in the lower half with
smaller, scarce pores, or nearly hyaline.

Dimensions. — Length of the three joints, a 0'03, b 0'07, c 0'06 ; breadth, a 0'04, b Oil, c 01.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Lophocorys acanthocephala, Haeckel.

Eucyrtidium acanthocepludum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. ix. fig. 8.

Shell rough, bottle-shaped, with two slight strictures. Length of the three joints = 5 : 11 : 7,
breadth = 4 : 12 : 10. Cephalis conical, with a large pyramidal horn of the same length, and three
smaller divergent accessory horns at the base of the three edges of the latter. Thorax campanulate,
nearly as long as the tapering abdomen (which in the figure of Ehrenberg is broken off). Pores
regular, circular, quincunciaL

Dimensions. — Length of the three joints, a 0'05, b Oil, c 0'07 ; breadth, a 0'04, b 012, c 01.

Habitat. — Fossil in Barbados.

3. Lophocorys bicornis, Haeckel.

Eucyrtidium Ucorne, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. xi. fig. 7.

Shell smooth, almost spindle-shaped, with two slight strictures. Length of the three joints =
2 : 8 : 3, breadth = 3:5:4. Cephalis hemispherical, with two stout, pyramidal, divergent horns of
twice the length. Thorax ovate, with seven to eleven transverse rows of small, regular, circular
pores (often very scarce in the upper half). Abdomen with two to four transverse rows of the same
pores. Mouth constricted, half as broad as the thorax.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'03 ; breadth, a 0'03, b 0'05, c 0'04.

Habitat. — Fossil in Barbados.

1422 THE VOYAGE OF H.M.S. CHALLENGER.

4. Lophocorys quadricornis, n. sp.

Shell rough, slenderly ovate, with two distinct strictures. Length of the three joints = 2:4:2,
breadth = 2:4:3. Cephalis ovate, with four very stout, three-sided prismatic horns ; the largest
is as long as the thorax and vertical upon the apex, the three smaller are as long as the cephalis
and diverge upwards from the base of the former. Thorax ovate, with large, irregular, roundish
pores, which are three to four times as broad as the small, circular pores of the first and the third
joint. Constricted mouth half as broad as the thorax.

Dimensions. — Length of the three joints, a 0'045, b 0'085, c 0'04 ; breadth, a 0'035, I 0-075, c 0'06.

Habitat.— South Atlantic, Station 332, depth 2200 fathoms.

5. Lophocorys bovicornis, n. sp. (PI. 69, fig. 12).

Shell rough, subovate, with two deep strictures. Length of the three joints =1:2:3, breadth =
1:3:4. Cephalis subspherical, with two divergent, curved horns of different lengths. Thorax cam-
panulate, with small, circular pores. Abdomen subspherical, truncate at both poles, twice as
broad as the constricted mouth, thorny, with very large, circular pores, four to six times as broad as
those of the smaller thorax.

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 0'09 ; breadth, a 0'04, b 0'09, c 012.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

Genus 622. Theocampe,1 n. gen.

Definition. — T heocorida (vel Tricyrtida eradiata aperta) with ovate abdomen,
broader than the constricted mouth. Cephalis without horn.

The genus Theocampe differs from the two preceding genera in the absence of horns
on the cephalis, and may, therefore be derived from Theocorys by reduction of the
apical horn. It bears to the latter the same relation as Tricolocampe does to Theocyrtis.

Subgenus 1. Theocampana, Haeckel.

Definition. — Pores of the thorax and the abdomen of nearly equal size and similar
form.

1. Theocampe ehrenbergii, Haeckel.

Dictyomitra ehrenbergii, Zittel, 1876, Zeitschr. d. deutseh. geol. Gesellsch., p. 82, Taf. ii.
fig. 5.

Shell ovate, smooth. Length of the three joints = 2: 3 : 13, breadth = 4: 7: 12. Cephalis
hemispherical. Thorax truncate, conical. Abdomen inflated, nearly spherical, twice as broad as
the constricted mouth. Pores of nearly equal size and form, small, regular, circular.

1 Theocampe = Divine caterpillar ; 6 ids,

REPORT ON THE RADIOLARIA. 1423

Dimensions.. — Length of the three joints, a 0-014, b Q'018, c 0'076 ; breadth, a 0'023, b 0'044,
c 0-073.

Habitat. — Fossil in the chalk of Northern Germany ; Brunswick (Zittel).

2. Theocampe pirum, Haeckel.

Eucyrtidium pirum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. x. fig. 14.
Eucyrtidium excellens, Biitschli, 1882, Zettschr. f. wiss. Zool., vol. xxxvi. p. 540, Taf. xxxiii.
fig. 31.

Shell ovate, smooth. Length of the three joints = 3 : 5 : 15, breadth = 6 : 10 : 16. Cephalis
hemispherical. Thorax truncate conical. Abdomen inflated, subspherical, three times as broad as
the constricted mouth. Pores of nearly equal size, regular, circular, in the thorax alternating, in
the abdomen disposed in five to six transverse, widely distant rows.

Dimensions. — Length of the three joints, a 0'015, b 0'025, c 0'075 ; breadth, a 0'03, b 0'05, c 0'08.

Habitat. — Fossil in the Tertiary rocks of Barbados.

3. Theocampe stenostoma, n. sp. (PL 66, fig. 23).

Shell about ovate, smooth. Length of the three joints = 3:4: 3, breadth = 6:8:9. Cephalis
hemispherical, large. Thorax and abdomen short, barrel-shaped. Both strictures deep. Abdomen
three times as broad as the constricted mouth. Pores of equal size, regular, circular, disposed in
oblique rows.

Dimensions. — Length of the three joints, a 0'03, b 0'04, c 0'03 ; breadth, a 0'06, b 0'08, c 0'09.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Theocampe nucula, HaeckeL

Eucyrtidium nucula, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 29, Taf. vii.
fig. 19.

Shell nearly ovate, rough. Length of the three joints = 3 : 5': 3, breadth =4 : 7 : 6. Cephalis
hemispherical, large. Thorax and abdomen inflated. Both strictures deep. Thorax broader than
the short abdomen, and twice as broad as the constricted mouth. Pores of equal size, regular,
circular, regularly disposed in transverse rows : three in the cephalis, six in the thorax, and three
in the abdomen.

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'03 ; breadth, a 0'04, b 0'07, c 0'06.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms ; also fossil in Barbados.

5. Theocampe cryptoprora, Haeckel.

Eucyrtidium cryptoprora, Ehrenberg, 1872, AbhandL d. k. Akad. d. Wiss. Berlin, p. 291,
Taf. vii. fig. 14.

Shell ovate, thin-walled, smooth, without external strictures, but with two distinct internal
annular septa. Length of the three joints = 2:7:4, breadth = 3:7:6. Cephalis, large, subspherical,

1424 THE VOYAGE OF H.M.S. CHALLENGER.

hyaline ; its lower half hidden in the upper part of the campanulate thorax. Mouth little con-
stricted, nearly as broad as the truncate abdomen. All pores equal, small, regular, circular.

Dimensions. — Length of the three joints, a 0-025, b 0'07, c 0'04 ; breadth, a 0'03, b 0'07, c 0'06.

Habitat. — Tropical Pacific, Stations 225 to 265, in various depths.

6. Theocampe ovulum, n. sp.

Shell perfectly ovate, thick-walled, smooth, without external strictures, but with two broad,
internal septa. Length of the three joints = 2 : 3 : 10, breadth = 3 : 6 : 8. Cephalis and thorax
together obtuse, conical, with obliquely ascending pores. Abdomen inflated, twice as broad as the
constricted mouth, with ten to twelve transverse rows of pores. All pores equal, small, regular,
circular.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 01 ; breadth, a 0'03, b 0'06, c 008.

Habitat. — Fossil in Tertiary rocks of Barbados and Sicily.

7. Theocampe cassis, Haeckel.

Eucyrtidium cassis, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291,
Taf. vii. fig. 20.

Shell bottle-shaped, thin-walled, with slight collar, but deep lumbar stricture. Length of the
three joints = 3:8:6, breadth = 2:7:7. Cephalis ovate. Thorax campanulate. Abdomen
inflated, twice as broad as the constricted mouth. Pores equal, regular, circular, disposed in
quincuncial rows.

Dimensions. — Length of the three joints, a 0'03, b 0'08, c 0-06 ; breadth, a 0'02, b 0'07, c 0'07.

Habitat. — Tropical Pacific (Philippines), Station 206, depth 2100 fathoms.

Subgenus 2. Theocamptra, Haeckel.

Definition. — Pores of the thorax and the abdomen of different sizes or dissimilar
forms.

8. Theocampe sphcerothorax, n. sp. (PL 66, fig. 25).

Shell almost ovate, rough. Length of the three joints = 2:5:10, breadth = 3:8:8. Cephalis
hemispherical. Thorax nearly spherical, truncate. Abdomen ovate, twice as broad as the
constricted mouth. Pores subregular, circular, quincuncially disposed, in the abdomen twice as
broad as in the thorax, and four times as broad as in the cephalis.

Dimensions. — Length of the three joints, a 0-025, b 0'05, c 01 ; breadth, a 0'03, b 0'08, c 0'08.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

REPORT ON THE RADIOLARIA. 1425

9. Theocampe versipellis, Haeckel.

Euc.yrlidium versipellis, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 72,
Taf. xi. fig. 14.

Shell slenderly ovate, rough. Length of the three joints = 3:5:13, breadth = 4:8:9. Cephalis
subspherical, without pores. Thorax hemispherical. Abdomen inflated, twice as broad as the
constricted mouth. Pores subregular, circular, quincuncially disposed, in the abdomen three
times as broad as in the thorax.

Dimensions. — Length of the three joints, a 0'025, b 0'05, c 013 ; breadth, 0'04, b 0'08, c 0'09.

Habitat. — Fossil in Barbados.

10. T/ieocampe megalopora, Haeckel.

Eucyrtidium megaloporum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291,
Taf. vii. fig. 19.

Shell almost ovate, with two distinct strictures. Length of the three joints = 2:6:3, breadth =
3:6:4. Cephalis hemispherical. Thorax ovate, inflated. Abdomen inversely ovate, two to three
times as broad as the constricted mouth. Pores subregular, circular, quincuncially disposed, twice
as broad in the large thorax as in the smaller abdomen.

Dimensions. — Length of the three joints, a 0'02, b O06, c 0'03 ; breadth, a 0'03, 6 O06, c 0'04.

Habitat. — Central Pacific, Station 267, depth 2700 fathoms.

11. Theocampe collaris, n. sp. (PL 66, fig. 18).

Shell almost ovate, with two distinct strictures. Length of the three joints = 3:3:6, breadth =
4:5:7. Cephalis obtuse conical, with five or six transverse rows of small pores. Thorax truncate
conical, with longitudinal furrows, each of which contains a single pore. Abdomen inflated, with
five or six distant, transverse rows of small, circular pores.

Dimensions. — Length of the three joints, a 0'03, b 0'03, c 0'06 ; breadth, a 0'04, b 0'05, c 0'07.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

12. Theocampe gemmata, Haeekel.

Eucyrtidium gemmatum, Ehrenberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. x. fig. 6.

Shell slenderly ovate, smooth, with two internal annular septa. Length of the three joints =
1:1:4, breadth =1:2:3. Cephalis campanulate, nearly as large as the truncate, conical thorax,
both with small, irregular, obliquely descending pores. Abdomen broader, twice as broad as the
constricted mouth, with numerous longitudinal ribs, alternating with single rows of small, circular
pores. (This and the following allied species approach to Cydadophora, by the abdominal ribs.)

Dimensions. — Length of the three joints, a 0'02, b 0'02, c 0'07 ; breadth, a 0'025, b 0'035,
c 0-045.

Habitat. — Fossil in Barbados.

(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 179

1426 THE VOYAGE OF H.M.S. CHALLENGER.

13. Theocampe costata, n. sp. (PL 66, fig. 24).

Shell almost ovate, with two sharp strictures. Length of the three joints = 2:4:8, breadth =
3:5:7. Cephalis hemispherical. Thorax twice as large, also hemispherical, both with regular,
circular, quincuncial pores. Abdomen broader, with numerous longitudinal ribs, alternating with
longitudinal rows of larger pores. Mouth constricted, half as broad as the thorax.

Dimensions. — Length of the three joints, a 0'02, & 0'04, c 0'08 ; breadth, a 0'03, & 0'05, c 0'07.

Habitat. — Indian Ocean, Sunda Straits (Eabbe), surface.

14. Theocampe cryptocephala, Haeckel.

Eucyrtidium cryptocepTialum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. xi. fig. 11.

Shell ovate, rough, with two distinct strictures. Length of the three joints = 1:2:4, breadth =
1:4:5. Cephalis subspherical, its lower half hidden in the campanulate thorax. Abdomen
subspherical, twice as broad as the constricted mouth. Pores subregular, circular, quincuncial,
twice as broad in the abdomen as in the thorax.

Dimensions. — Length of the three joints, a 0'02, I 0'04, c 0'07 ; breadth, a 0'025, & O07, c 0'09.

Habitat. — Fossil in Barbados.

Subfamily 2. THEOCAPSIDA, Haeekel, 1881, Prodromus, p. 436.

Definition. — T heocyrtida with the basal mouth of the shell fenestrated (vel
Trieyrtida eradiata clausa).

Genus 623. Theocapsa,1 Haeckel, 1881, Prodromus, p. 436.

Definition. — Theocapsida (vel Trieyrtida eradiata clausa), with an apical horn,
and a terminal lattice-plate on the mouth.

The genus Theocapsa, and the two following genera, represent together the small
subfamily of Theocapsida, or of those Trieyrtida in which the mouth is closed by a lattice-
plate, and external radial appendages are wanting. Theocapsa may be derived from
Theocorys by fenestration of the constricted mouth.

Subgenus 1. TJieocapsetta, Haeckel.

Definition. — Thorax of about the same size as the abdomen, or somewhat larger ;
pores of both nearly equal in size and similar in form.

1 Theocapsa = Divine capsule ; 6tos, KOL^/O..

REPORT ON THE RADIOLARIA. 1427

1. Theocapsa aristotelis, n, sp. (PI. 66, fig. 6).

Shell subovate, smooth, with two distinct strictures. Length of the three joints = 2:6:7,
breadth = 3:8:8. Cephalis hemispherical, with a conical, slender horn of about the same length.
Thorax and abdomen nearly equal in size, thin-walled, smooth, with small, regular, circular pores of
equal size. Basal pole rounded.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'07 ; breadth, a O03, b O08, c O08.

Habitat. — Mediterranean (Gibraltar), Atlantic (Canary Islands), surface.

2. Theocapsa plinii, n. sp.

Shell subovate, smooth, with two indistinct strictures. Length of the three joints = 2 : 5: 6,
breadth = 3:7:7. Cephalis hemispherical, with a pyramidal, thick horn of about the same length.
Thorax and abdomen of nearly equal size, thick-walled, rough, with large, regular, circular, double-
edged pores of equal size (twice as large and half as numerous as in the similar preceding species).

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'06 ; breadth, a O03, b 0'07, c 0'07.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

3. Theocapsa democriti, n. sp. (PI. 66, fig. 8).

Shell slender, ovate, spiny, with two distinct strictures. Length of the three joints = 3:5:6,
breadth = 4:7:7. Cephalis ovate, with numerous slender horns of the same length. Thorax and
abdomen with small, irregular, roundish pores of nearly equal size, armed with scattered slender
spines, half as long as the cephalic horns. Basal pole hemispherical, rounded.

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'06 ; breadth, a 0'04, b 0'07, c 0'07.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Theocapsa galeni, n. sp.

Shell broadly ovate, spiny, with two deep strictures. Length of the three joints = 2:7:6, breadth
= 3:8:7. Cephalis hemispherical, with two conical, divergent horns of the same length. Thorax
and abdomen with large, irregular, roundish pores of nearly equal size, armed with numerous short
spines, not larger than the pores. Basal pole conical, pointed.

Dimensions. — Length of the three joints, a 0'02, b 0'07, c 0'06 ; breadth, a 0'03, b 0'08, c 0'07.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

Subgenus 2. Thcocapsilla, Haeckel.

Definition. — Thorax of about the same size as the abdomen, or somewhat larger ;
pores of the two different in size or form.

1428 THE VOYAGE OF H.M.S. CHALLENGER.

4

5. Theocapsa wottonis, n. sp. (PI. 66, fig. 11).

Shell subovate, rough, with two deep strictures. Length of the three joints = 3:7:5, breadth =
3:9:8. Cephalis subspherical, with regular, circular, hexagonally-framed pores, and with a stout
pyramidal horn of the same length. Thorax conical, with subregular, circular, double-edged pores.
Abdomen hemispherical, smaller and thinner walled, with irregular, somewhat oblong pores. Basal
pole rounded.

Dimensions. — Length of the three joints, a O03, b 0'07, c 0'05 ; breadth, a 0'03, b 0'09, c 0'08.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

6. Theocapsa gessneri, n. sp.

Shell broadly ovate, with two deep strictures. Length of the three joints = 3:9:5, breadth =
4 : 10 : 4. Cephalis hemispherical, with a slender, conical horn of the same length. Thorax sub-
spherical, with small, regular, circular pores. Abdomen inversely conical, with few large, somewhat
oblong pores. Basal pole acute.

Dimensions. — Length of the three joints, a 0'03, b 0'09, c 0'05 ; breadth, a 0'04, b 01, c 0'04.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

7. Theocapsa aldrovandi, n. sp.

Shell slender, inversely ovate, with two slight strictures. Length of the three joints = 3 : 8 : 14,
breadth = 4 : 11 : 8. Cephalis subglobular, with a conical horn of the same length. Thorax also
subglobular, papillate, with regular, circular, hexagonally-framed pores. Abdomen inversely conical,
slender, with very small and numerous, subregular, circular pores. Basal pole ovate, pointed.

Dimensions.— Length of the three joints, a 0'03, b 0'08, c 014; breadth, a 0'04, b Oil, c 0'08.

Habitat. — Western Tropical Pacific, Station 225, -depth 4475 fathoms.

8. Theocapsa malpighii, n. sp. (PI. 66, fig. 15).

Shell inversely ovate, with two distinct strictures. Length of the three joints = 3 : 8 : 11,
breadth = 4:9:8. Cephalis hemispherical, with a conical horn of the same length. Thorax hemi-
spherical, thorny, with very small circular pores, surrounded by large, regular, hexagonal frames.
Abdomen inversely campanulate, with larger circular pores, and longitudinal ribs. Basal pole blunt,
conical.

Dimensions. — Length of the three joints, a 0'03, b 0'08, c Oil ; breadth, a 0'04, b 0'09, c 0'08.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Subgerms 3. Theocapsomma, Haeckel.

Definition. — Thorax much smaller than the abdomen, pores of the two nearly equal
in size and similar in form.

REPORT ON THE RADIOLARIA. 1429

9. Theocapsa linncei, n. sp. (PI. 66, fig. 13).

Shell slender, subcylindrical, rough, with two slight strictures. Length of the three joints =
1:3:6, breadth = 1:4:4. Cephalis hemispherical, with a pyramidal horn of twice the length
(sometimes, as in the specimen figured, one or two small accessory horns occur at its base). Thorax
hemispherical, thick-walled. Abdomen nearly cylindrical, twice as long as the thorax, thin-walled,
with a hemispherical, rounded basal pole. The specimen figured is an abnormal one, with some
deformities on the irregular abdomen ; in numerous other specimens the abdomen is cylindrical,
regular. Pores of the thorax and abdomen equal, very small and numerous, regular, circular, three
to four times as broad as the bars.

Dimensions. — Length of the three joints, a 0'02, b 005 to 0'06, c 01 to 012 ; breadth, a 0'03,
b 0-06 to 0-07, c O'OY to 0'08.

Habitat. — Cosmopolitan; Atlantic, Indian, and Pacific Oceans; many Stations at various depths.

10. Theocapsa forskalii, n. sp. (PL 66, fig. 9).

Shell slender, subcylindrical, smooth, with two slight strictures. Length of the three joints =
1:1:3, breadth = 1:2:2. Cephalis hemispherical, with a conical horn of half the length.
Abdomen three times as long as the thorax, of the same breadth, with the same irregular, roundish
pores, large and small intermingled. Basal pole rounded.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 0'09 ; breadth, a 0'03, b 0'06, c 0'06.

Habitat. — North Atlantic, Canary Islands, Station 353, depth 2965 fathoms.

11. Theocapsa ivolffii, n. sp. (PL 66, fig. 14).

Shell slender, spindle-shaped, very thick-walled, rough, without external strictures, but with
two broad internal girdles. Length of the three joints = 2 : 3 : 15, breadth = 4 : 5 : 7. Cephalis
with a short horn of the same length, conical. Abdomen five times as long as the thorax, with
the same subregular, circular pores. Basal pole inversely conical, with some larger, elongate pores.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 015 ; breadth, a 0'04, b 0'05, c 0'07.

Habitat. — Mediterranean, Crete, depth 1620 fathoms (Spratt).

12. Theocapsa pallasii, n. sp.

Shell subovate, thorny, with two slight strictures. Length of the three joints = 1:2:3,
breadth = 1:2:3. Cephalis ovate, with a pyramidal horn of the same length. Thorax and
abdomen with subregular, circular pores of medium size. Basal pole hemispherical. (Differs from
TJieocapsa mulleri, PI. 66, fig. 7, mainly in the larger number and smaller size of the regular, quin-
cuncial pores.)

Dimensions. — Length of the three joints, a 0'03, b 0'06, c 0'09 ; breadth, a 0'03, b 0'06, c 0'09.

Habitat. — Tropical Atlantic, Station 342, depth 1445 fathoms.

1430 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 4. Theocapsura, Haeckel.

Definition. — Thorax much smaller than the abdomen, pores of the two different in
size or form.

13. Theocapsa lamarckii, n. sp. (PI. 66, fig. 16).

Shell slenderly ovate, rough, with two distinct strictures. Length of the three joints = 1:2:7,
breadth = 1:4:5. Cephalis subspherical, with a conical horn of twice the length. Thorax
conical, with regular, circular pores. Abdomen three times longer, with subregular. hexagonal
pores of twice the size. Basal pole hemispherical, with very large, irregular, roundish pores.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 014 ; breadth, a 0'03, b 0408, c 01.

Habitat. — Indian Ocean, Madagascar (Rabbe), surface.

14. Theocapsa cuvieri, n. sp. (PI. 66, fig. 10).

Shell slenderly spindle-shaped, thorny, with two slight strictures. Length of the three joints =
1:3:6, breadth = 1:3:3. Cephalis subspherical, with a conical horn of the same length.
Thorax conical, spiny, with regular, circular, double-edged pores. Abdomen thinner-walled,
inversely conical, with irregular, roundish pores. Basal pole acute, with a bunch of larger spines.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 012 ; breadth, a 0'02, b 0'05, c 0'06.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

15. Theocapsa baerii, n. sp.

•

Shell slenderly spindle-shaped, smooth, with two indistinct strictures. Length of the three
joints = 1:2:8, breadth =2:3:4. Cephalis hemispherical, with a thick, conical horn of the same
length. Abdomen four times as long as the thorax. Pores in the thorax small and numerous,
regular, circular, in the abdomen twice as large, and irregularly roundish. Basal pole inversely
conical, acute. (Differs from Theocapsa wolffii, PI. 66, fig. 14, mainly in the shape of the pores.)

Dimensions. — Length of the three joints, a 0'015, b 0'03, c 012 ; breadth, a 0'03, I 0'04, c 0'06.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

16. Theocapsa rathkei, n. sp.

Shell slenderly conical, with two slight strictures. Length of the three joints =1:2:10,
breadth = 2:4:15. Cephalis small, with a large, conical horn of three times the length. Thorax
small, thorny, with small, irregular, roundish pores. Abdomen very large, as long and as broad as
the thorax, with irregular, polygonal or roundish, very large' pores, the margin of which is finely
denticulate. Basal pole truncate, rounded.

Dimensions. — Length of the three joints, a 0'02, b 0'05, c 0'2 ; breadth, a 0'04, b 0'08, c 0'3.

Habitat. — Fossil in Barbados.

REPORT ON THE KADIOLARIA. 1431

17. Theocapsa schwannii, n. sp.

Shell slenderly ovate, or pear-shaped, with two distinct strictures. Length of the three joints =
1:2:7, breadth = 2:4:7. Cephalis subspherical, small, with a stout, pyramidal horn of three
times the length. Cavity of the thorax subspherical, its thick wall with small, regular, circular,
hexagonally-framed pores. Abdomen very thick-walled, with crested bars, and very large,
irregular, roundish pores. Basal pole rounded, truncate.

Dimensions. — Length of the three joints, a O02, b 0'04, c 014 ; breadth, a 0'04, b 0'08, c 014.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

18. Theocapsa mulleri, n. sp. (PI. 66, fig. 7).

Shell slenderly ovate, or pear-shaped, spiny, with two indistinct strictures. Length of the three
joints = 1 : 2 : 3, breadth = 1 : 2 : 3. Cephalis ovate, with a stout, pyramidal horn of the same
length, and with a variable number of smaller accessory horns. Pores irregular, roundish, three
to four times as broad in the inflated abdomen as in the thorax. Basal pole hemispherical, spiny.

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'09 ; breadth, a 0'03, b 0'07, c 0'09.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

19. Theocapsa sarsii, n. sp.

Shell pear-shaped, with two indistinct strictures. Length of the three joints = 1 : 1 : 3, breadth
= 1:2:4. Cephalis with a thick horn of the same length, conical. Abdomen subspherical, very
thick-walled, its pores regular, circular, twice as broad as the bars, and three times as broad as
those of the thorax. Basal pole flat, rounded.

Dimensions. — Length of the three joints, a 0'04, b 0'05, c 012 ; breadth, a 0-05, b Oil, c 015.

Habitat. — Fossil in Barbados.

20. Theocapsa darwinii, n. sp. (PL 66, fig. 12).

Shell pear-shaped, with two distinct strictures. Length of three joints =1:1:5, breadth =
1:2:5. Cephalis hemispherical, with a conical horn of twice the length. Thorax campanulate,
with small, regular, circular pores. Abdomen broad, ovate, with larger, regular, circular, hexagon-
ally-franied pores. Basal pole hemispherical.

Dimensions— Length of the three joints, a 0'03, b 0'04, c 0'2 ; breadth, a 0'04, 6 0'08, c 0'2.

Habitat. — Central Pacific, Stations 263 to 274, depth 2350 to 2925 fathoms.

Genus 624. Tricolocapsa,1 Haeckel.

Definition. — T heocapsida (vel Tricyrtida eradiata clausa) without apical horn,
with a terminal lattice-plate on the mouth.

1 Tricoloeapsa = Three-jointed capsule ; r^ixa^tm, xa^a.

1432 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Tricolocapsa differs from the preceding Theocapsa in the loss of the
apical horn, and exhibits therefore to it the same relation that Theocampe bears
to Theocorys. In some species (PL 66, figs. 1, 3) a small tube begins to be
developed on the cephalis, and these may perhaps be separated as a peculiar genus,
Tricolopera.

Subgenus 1. Tricolocapsula, Haeckel.
Definition. — Thorax of about the same size as the abdomen, or larger.

1. Tricolocapsa theophrasti, n. sp. (PL 66, fig. 1).

Shell slenderly ovate, with two slight strictures. Length of the three joints = 2:8:5, breadth
= 3:7:5. Cephalis hemispherical, with a larger, tube-like, cervical pore at the collar stricture.
Thorax very thick-walled, with irregular, roundish, double-edged pores, smaller than the bars
between them. Abdomen smaller, inversely campanulate-conical, with very irregular pores.
Basal pole acute.

Dimensions. — Length of the three joints, a 0'02, I 0'08, c 0'05 ; breadth, a 0'03, I 0'07, c 0'05.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Tricolocapsa dioscoridis, n. sp. (PL 66, fig. 3).

Shell short and broad, with two deep strictures. Length of the three joints = 3:5:4, breadth =
4:7:5. Cephalis hemispherical, with a larger, tube-like, cervical pore above the collar
stricture. Thorax very broad, with irregular, large and spare, roundish pores. Abdomen much
smaller, inversely conical, wifii smaller pores. Basal pole obtuse.

Dimensions. — Length of the three joints, a 0'03, b 0'05, c 0'04 ; breadth, a 0'04, b 0'07, c 0'05.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Tricolocapsa linncei, n. sp. (PL 66, fig. 5).

Shell short and broad, with two deep strictures. Length of the three joints = 1:4:2, breadth
= 1:4:2. Cephalis hemispherical. Thorax thick-walled, inflated, with subregular, circular, double-
edged pores. Abdomen much smaller, thin-walled, with irregular, polygonal pores. Basal pole
hemispherical, rounded.

Dimensions. — Length of the three joints, a 0'02, b 0'08, c 0'05 ; breadth, a 0'03, b 0'08, c 0"05.

Habitat. — South Pacific, .Station 295, depth 1500 fathoms.

REPORT ON THE RADIOLARIA. 1433

4. Tricolocapsa decandollei, n. sp. (PI. 66, fig. 4).

Shell subovate, with two sharp strictures. Length of the three joints = 2:2:2, breadth =
3:4: 3'5. Cephalis campanulate. Thorax broader, ring-shaped. Abdomen inversely hemispheri-
cal. All three joints of the same length, thick-walled, with the same regular and peculiar reticula-
tion, the small circular pores being surrounded by square, elevated frames.

Dimensions. — Length of the three joints, a 0'07, b 0'07, c 0'07 ; breadth, a 010, b 014, c 012.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 2. Tricolocapsium, Haeckel.
Definition. — Thorax much smaller than the abdomen.

5. Tricolocapsa brownii, n. sp.

Shell ovate, very thick- walled, with two indistinct strictures. Length of the three joints =
2 : 4 : 7, breadth = 3 : 7 : 10. Cephalis flat, hemispherical. Thorax truncate, conical. Abdomen
inflated, inversely hemispherical. Pores regular, circular, of the same breadth as the bars, hexagonally-
framed, twice as large in the abdomen as in the thorax. Basal pole rounded.

Dimensions. — Length of the three joints, a 0'02, b 0'04, c 0'07 ; breadth, a 0'03, b 0'07, c 01.

Habitat. — Fossil in Barbados.

6. Tricolocapsa schleidenii, n. sp. (PI. 66, fig. 2).

Shell subconical, with two deep strictures. Length of the three joints = 2:3:6, breadth =
3:5:6. Cephalis subspherical. Pores subregular, circular, arranged in transverse girdles, three
in the broad thorax, six in the subglobular abdomen. Basal pole rounded.

Dimensions. — Length of the three joints, a 0'02, b 0'03, c 0'06 ; breadth, a 0'03, b 0'05, c 0'06.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Genus 625. Phrenocodon,1 n. gen.

Definition. — T heocapsida (vel Tricyrtida eradiata clausa) with an apical horn,
and a lattice-plate between thorax and abdomen.

The genus Phrenocodon differs from the two preceding genera in the remarkable
circumstance, that the basal lattice-plate closes not the terminal mouth itself, but the

1 Phrenocodon = Bell with diaphragm; @t>>i>/, x,u^uu.
(ZOOL. CHALL. EXP. — PAET XL. — 1886.) Rr 180

1434 THE VOYAGE OF H.M.S. CHALLENGER.

constricted opening between thorax and abdomen. It may therefore be regarded as a
Sethocapsa, which has developed a third, open, abdominal joint. The cephalis bears
an apical horn.

1. Phrenocodon clathrostomium, n. sp. (PI. 70, figs. 7, 8).

Shell campanulate-conical, with two deep strictures. Length of the three joints = 2:6:3,
breadth = 3 : 10 : 14. Cephalis hemispherical, with an oblique curved horn of the same length.
Thorax subconical, with polygonal, roundish pores, increasing in size towards the girdle. A perfect
fenestrated diaphragm, with irregular, roundish pores of very different sizes, separates the thorax
from the abdomen. The latter is composed of three parallel, circular rings, which are connected
by fifteen to twenty radial beams. As the middle ring is larger than the two others, the beams
between the large quadrangular pores are divergent in the upper, convergent in the lower girdle.
Short prolongations of the divergent beams form a coronal around the middle ring (compare fig. 7
profile, fig. 8 from below).

Dimensions. — Length of the three joints, a 0'02, 6 0'06, c 0'03 ; breadth, a 0'03, b 01, c 014.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Phrenocodon diaphragma, n. sp.

Shell campanulate-conical, very similar to that of the preceding species, but with abdomen and pro-
portions different. Length of the three joints = 1:3:2, breadth = 1:4:4. Abdomen cylindrical,
with two or three transverse rows of large quadrangular meshes (fifteen to twenty in each row),
without the characteristic inflexion of the preceding species, and without the coronal.

Dimensions. — Length of the three joints, a 0'02, b 0'06, c 0'034 ; breadth, a 0'02, b 0'08, c 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Section IV. STICHOCYRTIDA, Haeckel, 1862, Monogr. d. Radiol.,
p. 280, 312 (Pis. 75-80).

Stichocyrtida et Tetracyrtida, Haeckel, 1881, Prodromus, p. 437, 438.

Definition. — Cy rtoidea polythalamia, with annulated shell, divided by three to
six or more transverse, horizontal constrictions, into four to seven or more annular
joints. (The first joint represents the cephalis, the second the thorax, the third the
abdomen, all the following joints together a post-abdomen.)

REPOET ON THE RADIOLAEJA. 1435

Synopsis of the three Families and six Subfamilies of Stichocyrtida.

Family LXVIII. \ Mouth open, .... Stichopilida.

Podooampida.

Three radial apophyses. J Mouth closed, .... Stichoperida.

Family LXIX. \ Mouth open, ..... Stichophormida.

Phormocampida.

Numerous radial apophyses. J Mouth closed, ..... Stichophaenida.

Family LXX. ~\ Mouth open, ..... Stichocorida.

Lithocampida.

No radial apophyses. , j Mouth closed, . ... Stichocapsida,

Family LXVIII. PODOCAMPIDA, n. fam.

Artopilida et Artoperida, Stichopilida et Stichoperida, Haeckel, 1881, Prodromus, p. 437-439.

Definition. — S tichocyrtida triradiata. (Cyrtoidea with an annulated
shell, divided by three or more transverse constrictions into four or more annular joints,
and bearing three radial apophyses).

The family Podocampida comprises those Cyrtoideain which the lattice-
shell is composed of numerous (four to eight or more) annular joints, and bears three
external radial apophyses. It may be divided into two subfamilies, differing in the
shape of the terminal mouth. This is a simple wide opening in the Stichopilida (and
the united Artopilida), closed by a lattice-plate in the Stichoperida (and the united
Artoperida). The phylogenetic origin of the Podocampida may be found in the
Podocyrtida (p. 1314).

Very few forms only of the Podocampida were hitherto known, viz., Stichopilium
(Pterocodon) davisianum, and three fossil species from Barbados, figured by Ehrenberg ;
Artopera loxia (united by him with Lithornithium), and two species of Pteropilium
(sphinx and bombus, both united by him with the three-jointed Pterocanium). In
general, the triradiate Stichocyrtida are much rarer and much poorer in specific forms
than the triradiate Tricyrtida, their ancestors. We have observed altogether only
forty -four species, thirty Stichopilida, and fourteen Stichoperida ; the former are dis-
posed among seven, the latter among three genera.

The three radial apophyses appear either as lateral ribs or prominent wings in the
thorax (PI. 77, fig. 8—12), or as three terminal feet around the mouth (PI. 97, fig. 15).
Sometimes the ribs are replaced by three radial combs, or rows of spines, and these may
be united by three divergent beams, forming three vaulted bridges with numerous
bows (PL 75, figs. 10, 11). The lateral wings or ribs, as well as the terminal feet, are
either solid or fenestrated.

1436

L Subfamily

Stichopilida.
Mouth of the ter-
minal joint a simple
wide opening.

THE VOYAGE OF H.M.S. CHALLENGER.
Synopsis of the Genera of Podocampida.

Three lateral appen-
dices or wings (no
terminal feet).

Three terminal ap-
pendices or feet
at the peristome
(all with cephalic
horn).

Lateral wings are
latticed.

With horn,
"Without horn,

Three lateral ribs or f „ ...
crests prolonged I Feet solld'

Feet latticed,

into the three ter-
minal feet.

No lateral ribs.
Three terminal
feet free.

Feet solid,
Feet latticed,

II. Subfamily

Stiehoperida
Mouth of the terminal

joint closed by a

lattice-plate.

Last joint rounded, f Th ,ateral goM ribs (or rows o{ ines)
without a verti-
ine j
ith |

cal basal
(cephalis

spine
with

Three 1&teral latticed wi (or rows of
wings)>

Last joint conical, ("

pointed, with a] Three lateral solid ribs (cephalis with

vertical basal j an apical horn),

spine.

626. Stichopilium.

627. Artopilium.

628. Pteropilium.

629. Stichocampe,

630. Stichopterium.

631. Podocampe.

632. Stichopodium.

633. Stichopera.

634. Cyrt opera.

635. Artopera.

Subfamily 1. STICHOPILIDA, Haeckel, 1881, Prodromus, p. 439.

Definition. — Podocampida with the terminal mouth of the shell open (vel
Stichocyrtida triradiata aperta).

Genus 626. Stichopilium,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichopilida (vel Stichocyrtida triradiata aperta) with three solid
lateral ribs or wings, without terminal feet. Cephalis with a horn.

The genus Stichopilium is the most primitive among all Stichocyrtida, and repre-
sents perhaps the common ancestral form of this family. The shell is composed of
four or more joints (sometimes ten to twelve), has a wide open terminal mouth, and
three lateral solid wings or ribs (sometimes a little latticed on the base). Stichopilium
may be derived from Theopilium or Pterocorys by addition of new terminal joints.

Subgenus 1. Triacartus, Haeckel, 1881, Prodromus, p. 437.
Definition. — Shell with three annular strictures, and four distinct joints.

1 Stichopilium =Hat with a row of joints; <rr/xo?j «-iX/o».

REPORT ON THE RADIOLARIA. 1437

I Stichopilium cortina, n. sp.

Shell ovate, with three sharp strictures. Length of the four joints = 2:6:3: 4. Cephalis sub-
spherical, with a slender pyramidal horn of twice the length. The three edges of the horn are
prolonged into three strong divergent ribs, along the three first joints, and into three free conical
lateral spines, directed downwards, on the end of the third joint. The fourth joint is sub-
cylindrical ; its circular, terminal mouth half as broad as the third joint, which is the broadest.
Pores small, regular, hexagonal, with thin bars.

Dimensions. — Length of the shell (with four joints) 015, breadth 0'08. Length of the single
joints, a 0'02, b 0'06, c 003, d 0'04.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Stichopilium costatum, n. sp.

Shell conical, or nearly pyramidal, with three distinct strictures. Length of the four* joints =
3:5:8:4. Cephalis subconical, with a stout pyramidal horn of the same length. Thorax cam-
panulate, with six longitudinal ribs, from three of which in the middle arise three horizontal, conical,
free spines or wings, about as long as the cephalis. The third large prismatic joint bears twelve
parallel ribs, six new ribs being intercalated between the six former. Fourth joint short, cylin-
drical, without ribs, the wide open mouth not constricted, nearly as broad as the third joint, which
is the broadest. Pores small, irregular, polygonal, or roundish.

Dimensions. — Length of the shell (with four joints) 0'2, breadth 012. Length of the single
joints, a 0'03, b 0'05, c 0'08, d 0'04.

Habitat. — North Pacific, Station 244 (off Japan), depth 2900 fathoms.

3. Stichopilium bicorne, n. sp. (PL 77, fig. 9).

Shell conical, with three slight strictures. Length of the four joints = 4 : 14 : 5 : 3. Cephalis
large, conical, with two stout pyramidal, divergent horns of twice the length. Prom its base (in the
middle of the collar stricture) arise three internal, downwardly divergent ribs, which are prolonged
on the outside of the upper half of the thorax into three stout, pyramidal, lateral spines (similar to
the horns). The fourth joint, with wide open mouth, was the broadest, but not fully developed in
the single specimen observed. Pores subregular, hexagonal, with thin bars.

Dimensions. — Length of the shell (with four joints) 0'02, breadth 0'09. Length of the single
joints, a 0'02, b 0'07, c 0'025, d 0'015.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Stichopilium davisianum, Haeckel.

Pterocodon davisianus, Ehrenberg, 1872, Abhandl.d. k. Akad. d.Wiss. Berlin, p. 298, Taf. iifig. 10.
Cydadophora <te>m'aMa,Elirenberg, 187 2, Abhandl.d. k. Akad. d. Wiss. Berlin, p. 289, Taf. ii. fig.ll.
Emyrtidium davisianum, Haeckel, 1862, Monogr. d. Radiol., p. 328.
Pterocanium davisianum, Haeckel, 1862, Monogr. d. Radiol., p. 332.

Shell campanulate, conical, with three slight strictures. Length of the four joints = 2:3:4:3.
Cephalis hemispherical, with few small pores and a short conical horn. Thorax campanulate, with

1438 THE VOYAGE OF H.M.S. CHALLENGER.

larger circular pores, and three recurved, divergent, lateral wings of the same length. Third and
fourth joints each with three transverse rows of very large hexagonal pores. The similar form
described by Ehrenberg as Cydadophora davisiana, is either a mutilated specimen, or belongs to
Lithostrobus.

Dimensions. — Length of the shell (with four joints) 012, breadth 0'08. Length of the single
joints, a 0'02, 6 0'03, c 0-04, d 0'03.

Habitat. — North Atlantic, Greenland, depth 1000 to 1500 fathoms.

5. Stichopilium campanulatum, n. sp. (PI. 77, fig. 11).

Shell campanulate, with three slight strictures. Length of the four joints = 3:5:5:4. Cephalis
subovate, with an internal rod-cross, and a stout pyramidal horn of the same length. From
the middle of the collar stricture arise three divergent collar beams, which descend in the upper
half of the campanulate thorax as three divergent ribs, and are prolonged into three free horizontal
spines. (In the specimen figured these three wings are very short ; in another specimen, found after-
wards, there were three solid, pyramidal, horizontal spines, as long as the cephalic horn.) The third
joint is the broadest, of about the same length as the fourth. (The annular septum between the
two latter is by a mistake not figured). Pores subregular, circular, hexagonally framed.

Dimensions. — Length of the shell (with four joints) 017, breadth 012. Length of the single
joints, a 0'03, b 0'05, c 0'05, d 0'04.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Stichopilium triserratum, n. sp.

Shell slenderly campanulate, with three deep strictures. Length of the four joints = 2:4:6:3.
Cephalis hemispherical, with a stout pyramidal horn three times the length.. The three edges of the
horn are prolonged into three strong prominent ribs along the three first joints ; each rib bears a
series of stout, irregular, triangular teeth. The fourth joint is without ribs ; its constricted mouth
is half as broad as the third (broadest) joint. Pores subregular, circular.

Dimensions. — Length of the shell (with four joints) 015, breadth 0'08. Length of the single
joints, a 0'02, b 0'04, c 0'06, d 0'03.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 2. Stichopilidium, Haeckel.
Definition. — Shell with four or more annular strictures and five or more joints.

7. Stichopilium macropterum, Haeckel.

Rliopalocanmm varietas, Bury, 1862, Polycystins of Barbados, pi. xvii. fig. 7.

Shell slenderly conical, with five deep strictures. Length of the six joints = 2:5:4:3:3:6.
Cephalis hemispherical, with a stout conical horn of twice the length. Thorax campanulate, with

BEPOET ON THE KADIOLARIA. 1439

•

three large, triangular, widely divergent wings or ribbed solid spines, nearly as long as the shell.
The breadth of the joints increases gradually ; the last joint is the broadest, with wide open mouth.
Pores subregular, circular.

Dimensions. — Length of the shell (with six joints) 0'23, breadth 01. Length of the single
joints, a 0'02, b 0'05, c 0'04, d 0'03, e 0'03,/0'06.

Habitat. — Fossil in Barbados.

8. Stichopilium pectinatum, n. sp.

Shell slenderly conical, with nine sharp strictures. All ten joints have nearly equal length, and
increase gradually in breadth ; the last joint is the broadest, and twice as long as each of the others,
with wide open mouth. Cephalis subspherical, with a conical horn of the same length. Each joint
(excepting the first and the last) bears three lateral, nearly horizontal spines, and the bases of all the
spines are connected by three longitudinal, divergent ribs. Pores subregular, hexagonal. (Similar
to Stichopcra pectinata, PL 75, fig. 11.)

Dimensions. — Length of the shell (with ten joints) 0'32, breadth 01.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

9. Stichopilium thoracopterum, n. sp.

Shell slenderly ovate, twice as long as broad, with eleven slight annular strictures. The twelve
joints (excepting the second) are of nearly equal length, or alternately longer and shorter. The eighth
joint is the broadest, one and a half times as broad as the slightly constricted mouth. Cephalis
small, hemispherical, with a pyramidal horn of twice the length. Thorax (or second joint) cam-
panulate, twice to three times as long as each of the eleven other joints, with three longitudinal ribs,
prolonged into three divergent, slender, free spines. Pores small, regular, hexagonal.

Dimensions. — Length of the shell (with twelve joints) 0'22, breadth Oil. Length of each
joint (on an average) 0'015 to 0'0l7, thorax 0'035.

Habitat. — South Pacific, Station 296, depth 1825 fathoms.

Genus 627. Artopilium,1 Haeckel, 1881, Prodromus, p. 437.

Definition. — S tichopilida (vel Stichocyrtida triradiata aperta) with three
latticed lateral ribs or wings, without terminal feet. Cephalis with a horn.

The genus Artopilium (including also the genera Trictenartus, Pterocorythiiim,
Stichopterygium, and Clathropyrgus of my Prodromus) has a shell of the same form as
the preceding Stichopilium, but it differs in the fenestration of the three lateral ribs
or wings, which in the latter are solid. The limit between the two genera is often not

1 Artopilium — Loaf-hat; (Zfroj,

1440 THE VOYAGE OF H.M.S. CHALLENGER.

sharp. Artopilium may be also derived from the three-jointed Dictyoceras by addition
of new terminal joints.

Subgenus 1. Trictenartus, Haeckel, 1881, Prodromus, p. 437.
Definition. — Shell with three annular strictures and four joints.

1. Artopilium elegans, n. sp. (PI. 75, fig. 1).

Shell three-sided pyramidal, with three annular strictures. Length of the four joints = 1:2:9: 3.
Cephalis small, hemispherical, with two large, prismatic, divergent horns of three times the length.
The three prominent edges of the second and third joints are finely latticed and dentated, and at the
basal end of the third joint are prolonged into three stout, free, pointed, pyramidal, divergent wings,
about as long as the horns. The fourth joint is only as long as the second, three-sided prismatic,
its wide triangular mouth is armed with six parallel, vertical, slender teeth (two between every three
wings). Network very delicate and regular, in the first and second joints with circular, in the third
and fourth joints with small hexagonal meshes.

Dimensions. — Length of the shell (with four joints) 0'3, breadth of the third joint 0'3, of the
fourth 0-2. Length of the single joints, a 0'02, b 0'04, c 018, d 0'06.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

2. Artopilium longicorne, n. sp. (PI. 77, fig. 10).

Shell subovate, with three internal annular septa. Length of the four joints = 2:3:2:6.
Cephalis hemispherical, with a very large three-sided prismatic horn, nearly as long as the shell.
Along the three following joints arise three broad, triangular, latticed wings, about as long as the
shell. The fourth joint is the broadest, and twice as broad as the constricted mouth. Pores in the
two upper joints regular, circular, in the two lower and the three wings hexagonal.

Dimensions. — Length of the shell (with four joints) 013, breadth 0'09. Length of the single
joints, a 0'02, I 0'03, c 0"02, d 0'06.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

3. Artopilium cyrtopterum, n. sp. (PI. 77, fig. 12).

Shell subovate, with three sharp strictures. Length of the four joints = 1:2:3:3. Cephalis
subspherical, with a stout, pyramidal horn of twice the length. Along the second and third joints
arise three broad, triangular, latticed wings, about half as long as the shell. The third joint is the
broadest, and twice as broad as the constricted mouth. Pores subregular, circular.

Dimensions. — Length of the shell (with four joints) 018, breadth 01. Length of the single
joints, a 0'02, b 0'04, c 0'06, d 0'06.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

REPORT ON THE RADIOLARIA. 1441

Subgenus 2. Clathropyrgus, Haeckel, 1881, Prodromus, p. 439.
Definition. — Shell with four or more annular strictures, and five or more joints.

4. Artopilium trifenestra, n. sp. (PI. 75, fig. 7).

Clathropyrgus trifenestra, Haeckel, 1881, Prodromus et Atlas (loc. eit.).

Shell tower-shaped, nearly cylindrical, with nine deep strictures. The ten joints are of different
lengths and breadths. The third and fourth joints are the longest, twice as long as the first, fifth,
sixth, eighth, and ninth joints. The third, seventh, and tenth joints are the broadest, and nearly
twice as broad as the second and ninth joints. The mouth of the last joint is dilated. The second
joint bears three divergent ribs, and the third joint (as prolongations of these) three broad,
triangular, lattice-wings, and between the latter three large, ovate openings or windows, recalling
those in Clathrocanium (PL 64). Cephalis subspherical, with a pyramidal horn of twice the length.
Pores subregular, circular, hexagonally framed.

Dimensions. — Length of the shell (with ten joints) 0-28, of the first and ninth joints 0'02, of the
third and fourth joints 0-04 ; breadth of the third and seventh joints 0'08, of the second and ninth
joints 0'04.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

5. Artopilium trigonopterum, n. sp.

Shell in the upper half eampanulate-conical, in the lower half cylindrical, with seven internal
septa. The four middle joints are equal in length, each about twice as long as each of the two
first and of the two last joints. Cephalis hemispherical, with a conical horn of the same length.
Along the first three joints arise three broad, triangular, lattice-wings. Pores small, regular, hexa-
gonal, in the wings and the two first joints circular. The five lower joints are of equal breadth.

Dimensions. — Length of the shell (with eight joints) 0'2, breadth O'l. Length of the four
middle joints, each about 0'034, of the two first and the two last, each 0'0l7.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

6. Artopilium cornutella, n. sp.

Shell slenderly conical, without external strictures, but with twelve to fifteen internal annular
septa. All thirteen to sixteen joints are nearly equal or slightly different in length, but increase
gradually in breadth. Along the whole shell arise three narrow, divergent lattice-wings, increasing
in height towards the wide open mouth. Pores subregular, square, in three to four transverse
rows on each joint, half as large in the three wings as in the joints. Cephalis small, subspherical,
with a conical horn of twice the length. (In the specimen described the axis of the slender cone
was straight, in another incomplete specimen curved ; this may perhaps be a separate species,
Artopilium curvatum.)

(ZOOL. CHALL. EXP.— PART XL. — 1886.) Rr 181

1442 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Length of the shell (with sixteen joints) 0'3, basal breadth 012. Length of
each single joint (on an average), 0'02.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

7. Artopilium stichopterygium, n. sp. (PI. 75, fig. 8).

Stichopterygium tanypterum, Haeckel, 1881, Prodromus, p. 439, et Atlas.

Shell slenderly ovate, subconical, with five deep strictures. The four lower joints are nearly
equal in length, each about twice as long as each of the first two joints. The fourth and fifth joints
are the broadest. Along the whole shell arise three broad, triangular wings, which envelop
the long, slender, pyramidal horn of the cephalis. In the delicate and loose lattice-work of each
wing is a longitudinal series of six large, ovate apertures, one on each joint. The small pores of the
shell are irregular, polygonal, or roundish.

Dimensions. — Length of the shell (with six joints) 017, breadth 0'08. Length of each of the
four lower joints 0'03, of each of the two upper joints 0'015.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

8. Artopilium anomalum, Haeckel.

Eucyrtidium anomalum, Haeckel, 1862, Monogr. d. Eadiol., p. 323, Taf. vii. figs. 11-13.
Lithocampe anomala, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 839.
Stichopterygium anomalum, Haeckel, 1881, Prodromus, p. 439.

Shell five-jointed, with four internal septa, of a peculiar, irregular, and abnormal form.
Cephalis small, hemispherical, with an oblique, curved horn. Thorax inflated, campanulate, with
three large, latticed, and carinated protuberances. The third joint (the first abdominal joint) nearly
as large as the thorax, two to three times as long as the two last joints, the septa of which are
connected in a peculiar manner by a common nodal point on one side. Pores subregular, circular.
(Compare the detailed description of this remarkable species — perhaps the type of a peculiar genus,
Stichopterygium — in my Monograph, loc. cit.)

Dimensions — Length of the shell (with five joints) 015, breadth 01.

Habitat. — Mediterranean (Messina), surface.

Genus 628. Pteropilium,1 n. gen.

Definition. — S tichopilida (vel Stichocyrtida triradiata aperta) with three
latticed external ribs or wings, without terminal feet. No horn upon the cephalis.

The genus Pteropilium (confounded by Ehrenberg with Pterocaniu-m) differs
from this three-jointed form by addition of new terminal joints. The shell-form is in
general the same as in the preceding species, from which it may be derived by
phylogenetic loss of the cephalic horn.

1 Pteropilium= Winged hat ; TTSJOU,

REPORT ON THE RADIOLARIA. 1443

1. Pteropilium sphinx, Haeckel.

Pterocanium sphinx, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 255,
Taf. xvii. fig. 5.

Shell slenderly conical, with three slight strictures. Each of the two last joints as long as
the two first joints together. Cephalis hemispherical. Third joint with three prominent, divergent
ribs, which are prolonged along the fourth joint into three latticed, triangular wings, ending in
a free, strong, conical spine. Pores subregular, circular, twice as broad in the fourth joint
as in the third, and three times as broad as in the second joint.

Dimensions. — Length of the shell (with four joints) O'lo, of the single joints, a 0-02, b O03,
c 0-05, d 0-05 ; breadth of the third joint 0'09, of the fourth joint 0"06.

Habitat. — Fossil in Barbados.

2. Pteropilium bombus, Haeckel.

Pterocanium bombus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 82,
Taf. xvii. fig. 4.

Shell broadly conical, with three deep strictures. Length and breadth of the four joints,
gradually increasing giving the proportion 2:4:5:6. Cephalis hemispherical, second joint with
three prominent ribs, which are prolonged along the third and fourth joints into three slender,
triangular pointed wings, with few pores at the base. Pores of the shell subregular, circular.

Dimensions. — Length of the shell (with four joints) 0'17, of the single joints, a 0'02, b 0'04,
c 0-05, d 0'06 ; basal breadth Oil.

Habitat. — Fossil in Barbados.

3. Pteropilium pyramis, n. sp.

Shell three-sided, pyramidal, with five deep strictures. Length and breadth of the six joints
gradually increasing towards the wide mouth. Cephalis subconical. Along the four first joints
arise three slender, divergent ribs, which at the fifth joint become three free, triangular, latticed
wings, with long, descending, terminal spines. The sixth joint is free, without wings. Pores
irregular, roundish.

Dimensions.— Length of the shell (with six joints) 0'2, basal breadth 0'2.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Genus 629. Stichocampe* Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichopilida (vel Stichocyrtida triradiata aperta) with three solid
lateral ribs or wings, which are prolonged into three solid terminal feet. Cephaiis with
a horn.

i Stichocampe = Caterpillar with a row of joints; ern'xof,

1444 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Stichocampe, together with the three following genera, represent a
peculiar small group among the Stichocyrtida, differing from all other members of this
family in the possession of three free terminal feet around the open mouth. In the
two genera, Stichocampe and Stichopterium, these three feet are the terminal prolonga-
tions of three lateral ribs or crests, while in the two genera developed later, Podocampe
and Stichopodium, the three original ribs are lost, and only the three free feet
remain. Stichocampe (the most primitive of these four genera) may be derived from
Theopodium by addition of new joints.

1. Stichocampe divergens, n. sp.

Shell spiny, broadly pyramidal, with six deep strictures. Seven joints gradually increasing in
breadth and length, the seventh twice as broad as the fourth. Pores subregular, circular, hexagon-
ally framed. The prominent edges of the pyramis are prolonged over the wide mouth into three
slender, straight, divergent feet, half as long as the shell

Dimensions. — Length of the shell (with seven joints) 0'3, of the last joint O06, of the fourth
0-03 ; breadth 0'25.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Stichocampe convergens, n. sp.

Shell smooth, slenderly pyramidal, with eight distinct strictures. All nine joints nearly equal in
length. Pores regular, circular, forming three or four transverse rows in each joint. The smooth
edges of the pyramis are prolonged over the wide mouth into three slender, slightly curved, and
convergent feet, twice as long as one joint.

Dimensions. — Length of the shell (with nine joints) 0'25, of each joint, about 0'35 ; breadth Oil.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

Genus 630. Stichopterium,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichopilida (vel Stichocyrtida triradiata aperta), with three
lateral ribs or wings, which are prolonged into three latticed, terminal feet. Cephalis
with a horn.

The genus Stichopterium has in general the same shell-formation as the nearly
allied Stichocampe, but differs from this ancestral form in the fenestration of the three
terminal feet. It corresponds, therefore, to Pterocanium among the Tricyrtida.

1 Stichopterium = Row-wing ; arix»s , »W j<o».

REPORT ON THE EADIOLARIA. 1445

1. Stichopterium pterocanium, n. sp.

Shell campanulate, with three distinct strictures. Length of the four joints = 2:3:4:3.
Cephalis subspherical, with a conical horn of twice the length. Pores regular, hexagonal, with thin
bars. From the collar stricture arise three divergent ribs, which in the fourth joint become
latticed and prolonged over its mouth into three slender, pyramidal, latticed, divergent feet, nearly as
long as the shell. (Similar to Pterocanium bicorne, PL 73, fig. 5, but with four distinct strictures.)

Dimensions. — Length of the shell (with four joints) O12, breadth O'l. Length of the single
joints, a 0'02, b 0'03, c 0'04, d 0'03.

Habitat. — South Pacific (off Patagonia), Station 304, surface.

2. Stichopterium virgineum, n. sp.

Shell three-sided, pyramidal, with four sharp strictures. Length of the five joints =
1:4:3:2:1. Cephalis hemispherical, with a pyramidal horn three times the length. Pores
subregular, circular, in the second campanulate joint twice or three times as broad as in the four
other joints. From the base of the cephalic horn arise three divergent ribs, which descend over the
whole shell, and in the fourth joint become latticed and prolonged over the wide mouth of the fifth
joint into three latticed, pyramidal feet, as long as the second joint. (Similar in general form to
Pterocanium virgineum, PI. 73, fig. 6.)

Dimensions. — Length of the shell (with five joints) 0'22, breadth 016. Length of the single
joints, a 0'02, b 0'08, c 0'06, d 0'04, e 0'02.

Habitat. — Central Pacific, Station 281, surface.

3. Stichopterium dictyopodium, n. sp.

Shell subovate, with five internal annular septa. The third and the fourth joints are about
twice as long as the two first and the two last joints. The fifth joint is the broadest. Pores
small and numerous, regular, circular. The three first joints are without ribs. From the third
stricture arise three divergent, triangular, latticed wings, which descend along the three last joints,
and are prolonged over the wide mouth as three slender, fenestrated, divergent feet, two-thirds as
long as the shell.

Dimensions. — Length of the shell (with six joints) 0'18, breadth 0'12. Length of the two
middle joints 0'04, of the four others 0'02 to 0'03.

Habitat. — South Pacific, Station 288, surface.

Genus 631. Podocampe,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S t i c h o p i 1 i d a (vel Stichocyrtida triradiata aperta), without lateral
ribs or wings, but with three free, solid, terminal feet. Cephalis with a horn.

1 Podocampe = Caterpillar with feet ;

1446 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Podocampe is next allied to Stichocampe, and has also three solid, free
feet around the mouth, but it has lost the three lateral ribs of the latter. It corre-
sponds to Podocyrtis among the Tricyrtida, and may be derived from this by
addition of new terminal joints.

1. Podocampe tripodiscus, n. sp.

Shell ovate, with three annular septa. The fourth joint is the broadest, and as long as the
three other joints together. Cephalis hemispherical, with a pyramidal horn of twice the length.
Mouth constricted, with three convergent, curved, triangular feet, half as long as the last joint.
Pores subregular, circular. (Similar to Podocyrtis pedicellaria, PL 72, fig. 8, but larger, with more
slender feet, and four joints instead of three.)

Dimensions. — Length of the shell (with four joints) 0'2, of the last joint 01 ; breadth 012.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Podocampe trictenota, n. sp. (PI. 97, fig. 15).

Shell slenderly ovate, nearly spindle-shaped, with three annular septa. The third joint is the
broadest, somewhat longer than the second and third joints, and three times as long as the hemi-
spherical cephalis, which bears a strong pyramidal horn of twice the length. Along the two first
joints arise three divergent, dentate crests, each with four to six strong pyramidal teeth. Mouth
strongly constricted, only as broad as the cephalis, with three conical, vertical, parallel feet, as long
as the cephalis. Pores regular, circular, hexagonally framed.

Dimensions. — Length of the shell (with four joints) 014, of the third joint 0'06, of the last 0'04;
breadth 0'08.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Podocampe conica, n. sp.

Shell conical, with five distinct strictures. Six joints gradually increasing in length and
breadth. The sixth joint is the broadest, and twice as long as the fifth joint, three times as long
as the fourth. Cephalis conical, with a stout, conical horn of the same length. Mouth little con-
stricted, with three divergent, conical feet, half as long as the shell. Pores subregular, circular.
(Similar to Podocyrtis lithoconus, PL 72, fig. 3, but with six joints instead of three, and with
divergent, slender feet.)

Dimensions. — Length of the shell (with six joints) 018, of the last joint O'OG; breadth 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Podocampe cornuta, n. sp.

Shell slenderly conical, with seven distinct strictures. Eight joints of nearly equal length,
gradually increasing in breadth. Along the three last joints arise three prominent crests, which are

REPORT ON THE RADIOLAR1A. 1447

prolonged over the wide mouth into three divergent, conical feet, half as long as the shell. Cephalis
hemispherical, with a conical, slender, curved horn, three times the length. Pores subregular,
hexagonal.

Dimensions. — Length of the shell (with eight joints) 016, of each single joint (on an average)
0-02; basal breadth 0'07.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 632. Stichopodium,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S t i c h o p i 1 i d a (vel Stichocyrtida triradiata aperta) without lateral
ribs or wings, but with three free latticed terminal feet. Cephalis with a horn.

The genus Stichopodium differs from the preceding genus Podocampe in the fenes-
tration of the three free terminal feet. It agrees in this character with the genus
Stichopterium, and may be derived either from this by loss of the lateral ribs, or
from the three-jointed Pterocanium by addition of new shell-joints.

1. Stichopodium dictyopodium, n. sp. (PL 75, fig. 6).

Shell subcylindrical, in the upper third conical, with six or seven internal annular septa. All
seven or eight joints are about equal in length, except the small hemispherical cephalis, which is
scarcely half as long, and bears an oblique, conical horn of the same length. Pores small and
numerous, regular, circular, quincuncial. The last joint with wide open mouth, and a peristome of
three large, triangular, latticed, shovel-shaped, vertical feet.

Dimensions. — Length of the shell (with seven joints) 0'2, breadth O'll. Length of each single
joint about 0'03, of the feet 0'03.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subfamily 2. STICHOPERIDA, Haeckel, Prodromus, p. 439.

Definition. — P odocampida with the terminal mouth of the shell fenestrated
(vel Stichocyrtida triradiata clausa).

Genus 633. Stichopera* Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichoperida (vel Stichocyrtida triradiata clausa) with three
solid lateral ribs, or three longitudinal combs of spines. Cephalis with a horn.

1 Stichopodium = Row-foot ; OTI'XOS, •x-^ioi/. * Stichopera = Row-pouch ;

1448 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Stichopera, and the two following genera, represent the small subfamily
of Stichoperida, or those triradiate Stichocyrtida in which the terminal mouth is closed
by lattice-work. In Stichopera the three radial appendages are either solid lateral ribs
or longitudinal combs of spines ; the closed basal part of the shell is rounded, not
pointed. It may be derived either from Stichopilium by closure of the mouth, or from
Lithornithium by increase of the number of the joints.

Subgenus 1. Stichoperina, Haeckel.
Definition. — Shell with three solid radial ribs, or longitudinal dentate crests.

1. Stichopera ovata, n. sp.

Shell ovate, with three distinct strictures. Length of the four joints = 2:3:4:6. The fourth
joint is the broadest, and twice as long as the second, with hemispherical basal pole. Cephalis
hemispherical, with a conical horn of twice the length. Along the second and third joints descend
three prominent divergent ribs, which disappear in the middle zone of the fourth joint. Pores
regular, circular.

Dimensions. — Length of the shell (with four joints) 015, breadth O'l. Length of the single
joint, a 0-02, 6 0"03, c 0'04, d 0'06.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Stichopera lagena, n. sp.

Shell bottle-shaped, with six sharp strictures ; the upper half is slender, conical, and composed
of six joints of nearly equal length, the lower half is formed only by the last subspherical joint.
Cephalis subspherical, with a pyramidal horn of the same length. From its base arise three
divergent ribs, which attain the greatest height in the fourth joint, and disappear in the sixth joint.
(Similar to Stichophcena ritteriana, PI. 75, fig. 12, but only with three ribs and seven joints.) Pores
regular, hexagonal.

Dimensions. — Length of the shell (with seven joints) 0'25. Length of each joint O02 to 0-025,
of the last joint 012 ; breadth 014.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Stichopera serrata, n. sp.

Shell bottle-shaped, with eight deep strictures. The first eight joints are little different in
length, and form together a slender cone, while the last joint is four times as long (half as long as
this cone), and subspherical. Cephalis conical, with a slender, prismatic horn of three times the
length. Along the whole shell arise three divergent, serrate ribs, which disappear towards the
hemispherical, basal pole. Pores subregular, hexagonal.

REPORT ON THE RADIOLARIA. 1449

Dimensions. — Length of the shell (with nine joints) 0'21, breadth 0'08 ; length of each joint
0-016 to 0-019, of the last joint 0'07.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

Subgenus 2. Sticholagena, Haeckel.

Definition. — Shell with three radial combs or longitudinal rows of isolated spines
(instead of the three radial ribs).

4. Stichopera pectinata, n. sp. (PI. 75, fig. 11).

Shell club-shaped, with nine sharp strictures. The nine upper joints increase gradually in
length and breadth, and are together three times as long as the inflated, inversely campanulate and
rounded last joint. Each joint (excepting the first and the last) bears three thin, bristle-shaped
spines, which are directed obliquely upwards. Cephalis subspherical, with a slender, conical horn
of twice the length. Pores subregular, in the upper half circular, in the lower hexagonal.

Dimensions. — Length of the shell (with ten joints) 0'22, breadth 0'09 ; length of the eighth
and ninth joints 0'02, of the last joint 0'075.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

5. Stichopera clavata, n. sp.

Shell club-shaped, with eight sharp strictures, very similar in form and structure to that of
the preceding species, but differing from it in the club-like form of the inflated last joint, which
is nearly half as long as the shell ; its lower half is broader than the upper (the reverse being the
case in the preceding species). The lateral spines of the three combs are not directed upwards,
but downwards. Cephalis with a curved, conical horn of the same length.

Dimensions. — Length of the shell (with nine joints) 0'2, breadth 0-08 ; length of the eighth
joint 0-02, of the last joint 0'09.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

6. Stichopera verticillata, n. sp.

Shell club-shaped, with ten sharp strictures, similar in form and structure to that of the two
preceding species, but differing from them in the ovate form of the slender last joint, which is one-
third as long as the whole shell, and five times as long as the preceding joint. The lateral spines
of the three combs are directed nearly horizontally, and are much more numerous, each joint
(excepting the first and last) bears six to twelve spines (two, three, or four in each radius). They
form together about thirty horizontal verticils, each with three spines. Cephalis with a curved,
conical horn of three times the length.

(ZOOL. CHALL. EXP. — PAET XL. 1886.) Kr 182

1450 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Length of the shell (with eleven joints) 0'28, breadth 0'09 ; length of the tenth
joint 0'02, of the last joint 01.

Habitat. — Central Pacific, Station 2*71, depth 2425 fathoms.

Genus 634. Cyrtopera,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichoperida (vel Stichocyrtida triradiata clausa) with three
latticed lateral wings, or three longitudinal rows of lattice-wings. Cephalis with
a horn.

The genus Cyrtopera differs from the preceding Stichopera in the fenestration of
the three lateral wings, and bears therefore to it the same relation that Sethornithium
exhibits to Lithornithium among the Tricyrtida.

Subgenus 1. Artopera, Haeckel, 1881, Prodromus, p. 438.
Definition. — Shell with three annular strictures and four joints.

1. Cyrtopera thoracoptera, n. sp. (PL 75, fig. 3).

Artopera thoracoptera, Haeckel, 1881, Prodromus et Atlas (loo cit.).

Shell inflated, with three very deep strictures. Length of the four joints = 2:7:8:6. Cephalis
hemispherical, with a slender, prismatic horn, half as long as the shell. Thorax subspherical, in
its middle third with three latticed, triangular wings of half the length. Abdomen with' inflated
third, and inversely hemispherical fourth joint ; the third is the broadest. Pores subregular,
hexagonal, with thin bars.

Dimensions. — Length of the shell (with four joints) O23. Breadth of the third (broadest) joint

013. Length of the single joints, a 0'02, b 0'07, c 0'08, d 0'06.
Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Cyrtopera ornithoptera, n. sp.

Shell broadly ovate, with three slight strictures. Length of the four joints = 1:2:3:4.
Cephalis hemispherical, with a slender, pyramidal horn of three times the length. Along the
second and third joints arise with broad base three latticed, triangular wings, nearly as long as the
whole shell. Abdomen inflated. The fourth joint is the broadest and longest, with hemispherical
basal pole. Pores subregular, hexagonal. (Similar to Artopilium longicorne, PI. 77, fig. 10, but
with more closely reticulated network, and perfectly closed mouth.)

Dimensions. — Length of the shell (with four joints) 0'2. Breadth of the fourth (broadest) joint

014. Length of the single joints, a 0'02, I 0'04, c 0'06, d 0'08.
Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

• J Cyrtopera = Basket-pouch ;

REPORT ON THE RADIOLARIA. 1451

3. Cyrtopera gasteroptera, n. sp.

Shell slenderly ovate, with three distinct strictures. Length of the four joints = 2:6:7:6.
Cephalis subspherical, with a stout pyramidal horn of the same length. The three following joints
have nearly equal length ; the third is the broadest. The thorax exhibits three divergent solid
ribs ; as prolongations of these, three descending latticed wings, of about the same length, arise from
the third joint, with broad triangular base. The fourth joint is inversely conical, blunt. Pores
irregular, roundish. (Similar to Hexalatractus fusiformis, PL 68, fig. 13, but with three wings and
four joints.)

Dimensions. — Length of the shell (with four joints) 0'21. Breadth of the third (broadest) joint
Oil. Length of the single joints, a 0'02, & 0'06, c 0'07, d 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 2. Cyrtolagena, Haeckel, 1879, Atlas (PI. 75).
Definition. — Shell with four or more annular strictures, and five or more joints.

4. Cyrtopera laguncula, n. sp. (PI. 75, fig. 10).

Cyrtolagena laguncula, Haeckel, 1879, Manuscript et Atlas (loc. cit.).

Shell bottle-shaped, with seven sharp strictures ; the upper part is slender, conical, composed of
seven joints of nearly equal length ; the lower part is only formed by the spherical last joint.
Cephalis subspherical, with a slender curved horn of three times the length. Along the whole shell
arise three longitudinal combs or rows of ascending spines (three on each joint, fifteen on the last).
These are connected by three divergent longitudinal rods, so that three elegant fenestrated ribs are
formed (each rib with one series of large square meshes). Pores in the seven upper joints regular,
circular, in the last polygonal, irregular and larger.

Dimensions. — Length of the shell (with eight joints) 017, of the last joint 0'08 ; breadth 0-08.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

5. Cyrtopera lagenella, n. sp.

Shell bottle-shaped, with twelve sharp strictures, very similar in form and structure to the pre-
ceding species; but instead of the three simple fenestrated ribs there arise here, along the shell, three
series of short, triangular, latticed wings. The four first and the last joints are without wings. The
hemispherical cephalis bears a curved conical horn, as long as the subspherical last joint. The
twelve joints of the upper conical part are nearly equal in length, with regular, small, hexagonal pores.
The last inflated joint is one-third as long as the shell, and has larger, irregular, polygonal pores.

Dimensions. — Length of the shell (with thirteen joints) (V25, of the last joint 0'08 ; breadth 01.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

1452 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 635. Artopera? Haeckel, 1881, Prodromus, p. 438.

Definition. — S tichoperida with three solid lateral ribs or wings, and with a
vertical basal spine on the end of the pointed last joint. Cephalis with a horn.

The genus Artopera differs from its ancestral genus, Stichopera, in the development of
a vertical terminal spine on the end of the last joint, and bears therefore to it the same
relation that Rhopalatractus exhibits to Rhopalocanium among the Tricyrtida.

1. Artopera loxia, Haeckel.

• Lithornifhium loxia, Ehrenberg, 1854, Mikrogeol., Taf. xxxvi. fig. 8; Abhandl. d. k. Akad. d.

"Wiss. Berlin, 1875, p. 78, Taf. iv. fig. 8.

Shell spindle-shaped, with three deep strictures. Length of the four joints = 2:5:5:4.
Cephalis subspherical, hyaline, without pores, with a thick conical horn of the same length. From
the two following joints, which are nearly equal in size and of campanulate form, arise, with broad
base, three divergent, slender, triangular wings. The fourth joint is smaller, inversely conical, and
bears on the basal pole a strong, three-sided pyramidal, vertical spine, half as long as the shell.
Pores subregular, circular.

Dimensions. — Length of the shell (with four joints) 018, breadth 0'07. Length of the single
joints, a 0"02, I 0'055, c 0-055, d 0'05.

Habitat. — Fossil in Barbados.

2. Artopera motacilla, n. sp.

Shell spindle-shaped, with three distinct strictures. Length of the four joints = 1:2:3:2.
Cephalis subspherical, with a conical horn of twice the length. From the second joint arise three
longitudinal, smooth, divergent ribs, which are prolonged over the third joint, and terminate at the
third stricture in three short, conical teeth. The fourth is inversely conical, and bears on the
basal pole a strong, vertical, cylindrical spine, nearly half as long as the shell. Pores subregular,
circular, hexagonally framed. (Similar to Ehopalatradus pentacanthus, PL 68, fig. 11, but differing
in the presence of three sharp strictures, and a large, conical, basal joint).

Dimensions. — Length of the shell (with four joints) 018. Breadth of third (broadest) joint 0'09.
Length of the single joint, a 0'02, b 0'04, c 0'06, d 0'04.

Habitat. — Western Tropical Pacific (Philippine Sea), Station 198, depth 2150 fathoms.

3. Artopera fusiformis, n. sp.

Shell spindle-shaped, with three distinct strictures. Length of the four joints = 2:3:5:5.
Cephalis conical, with a strong, conical horn of the same length. Along the three first joints arise

1 Artopera = Bread-pouch; oJjrof, irti(>ec.

REPORT ON THE RADIOLARIA. 1453

three divergent, irregularly dentate ribs, which at the second joint bear stronger, pyramidal teeth,
also at the third stricture a strong, terminal tooth. Fourth joint without ribs, inversely conical,
with a strong, conical, terminal spine of half the length on the basal pole. Pores subregular, circular,
double-edged.

Dimensions. — Length of the shell (with four joints) 015. Breadth of the third (broadest) joint
0-08. Length of the single joint,, a 0'02, b O03, c 0'05, d 0'05.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Family LXIX. PHORMOCAMPIDA, n. fam.

Artophormida et Ariopliienida, Stichophormida et Stichophaenida, Haeckel, 1881, Prodromus, pp. 438, 439.

Definition. — S tichocyrtida multiradiata. (Cyrtoidea with an annulated
shell, divided by three or more transverse constrictions into four or more annular
joints, with numerous, four to nine or more, radial apophyses.)

The family Phormocampida comprises those Cyrtoidea in which the
lattice-shell is composed of numerous (four to eight or more) annular joints, and bears
numerous (four to eight or more) radial apophyses. We divide it into two
subfamilies, differing in the shape of the terminal mouth. This is a simple
wide opening in the Stichophormida (and the united Artophormida), closed by a lattice-
plate in the Stichophsenida (and the united Artophsenida). The phylogenetic origin of
the Phormocampida may be found in the Phormocyrtida.

Three fossil forms only of Phormocampida were hitherto known, two of which were
described by Stohr as Eucyrtidium acutatum and Lithocampe jimbriata, the third by
Ehrenberg as Eucyrtidium barbadense ; the latter belongs to Artophormis, the two
former to Oyrtophormis. All the other Phormocampida here described, forming
together thirty -one species, are new; twenty -two of them belong to the Stichophor-
mida, and nine to the Stichophsenida. The latter are disposed in two, the former in
four genera.

The number of the radial apophyses is sometimes six or nine, sometimes twelve or
more, usually a multiple of three. They are either lateral ribs or wings (PI. 75,
figs. 2, 5, 12), or terminal feet (PI. 77, figs. 13 to 18). Usually they are solid,
not latticed, and not strongly developed. The majority of Phormocampida have pro-
bably been derived from Phormocyrtida by growth of the abdomen, which becomes
annulated by transverse constrictions. Some forms, however, may be derived
from similar Podocampida, by interpolation of three to six or more secondary apophyses
between the three primary or perradial apophyses.

1454 THE VOYAGE OF H.M.S. CHALLENGER.

Synopsis of the Genera of Phormocampida.

\ Lateral ribs prolonged into the
Shell conical or pyra- j terminal feet> ' ' 636' Stichophormis.

I. Subfamily

Stichophormida.
Mouth of the terminal
joint open, simple.

II. Subfamily

Stichophaenida.
Mouth of the terminal •
joint closed by a
lattice-plate.

i jjjm- ,
midal. Mouth wide NQ ^^ ^s ^ f

'

_
open, not constricted. [ ^^ _ _ _ ' ^ Phormocampe.

„, ,, . ,, f Lateral ribs prolonged into the

bhell ovate or spindle- • i * t

t

v spine- • i * t CQO 4 .» T. •

, , T., ,f terminal feet, .... 638. Artopliormis.
shaped. Mouth more I

or less constricted. j ^ ^^ ^ Feet ^ ^

[ minal, ..... 639. Cyrtophormis.

Six radial ribs or wings, .... . 640. Artoplieena,

Nine radial ribs or wings, ..... ..641. Stichophsena.

Subfamily 1. STICHOPHORMIDA, Haeckel, 1881, Prodromus, p. 439.

Definition. — P hormocampida with the terminal mouth of the shell open (vel
Stichocyrtida multiradiata aperta).

Genus 636. Stichophormis,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichophormida (vel Stichocyrtida multiradiata aperta) with
conical or pyramidal shell, bearing in its wall numerous lateral ribs, which are prolonged
into terminal feet. Mouth not constricted.

The genus Stichophormis and the three following genera represent together the sub-
family of Stichophormida, or of those multiradiate Stichocyrtida in which the mouth
remains open ; they may be derived therefore either from the Theophormida by in-
creasing the number of the shell-joints, or from the Stichopilida by the interpolation
of new radial ribs between the three primary ribs. Stichophormis may have been
derived in the former way from Theophormis.

Subgemis 1. Stichophormium, Haeckel.

Definition. — Shell with six prominent longitudinal ribs, which are prolonged into six
(sometimes five or seven) divergent free feet over the mouth.

1 . Stichophormis pyramidalis, n. sp.

Shell slenderly pyramidal, with three annular septa, and six prominent radial ribs, which arise
from the collar-septum, and are prolonged on the mouth into six free, divergent, pyramidal feet,

1 Stiehophormis = Row-basket ;

REPOET ON THE RADIOLARIA. 1455

about as long as the shell. Length of the four joints = 2:3:5:8. Cephalis subspherical, with a
stout, pyramidal horn of twice the length. Pores regular, circular.

Dimensions.— Length of the shell (with four joints) 0'18, basal breadth 0'08. Length of the
single joints, a O02, b 0'03, c 0'05, d O08.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

2. Stichophormis lucerna, n. sp.

Shell slenderly pyramidal, with three annular septa and six prominent radial ribs, which arise
from the second stricture, and are prolonged over the mouth into six free, divergent, cylindrical
feet, half as long as the shell. Length of the four joints = 1 : 2 : 3 : 15. Cephalis hemispherical,
with a prismatic horn of the same length. Pores in the first and second joints very small and
scarce, in the third campanulate joint circular, hexagonally framed, in the colossal fourth joint very
large, polygonal (each about as large as the third joint).

Dimensions. — Length of the shell (with four joints) 0'4, basal breadth 0'2. Length of the
single joints a 0'02, b 0'04, c 0'06, d 0'3.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Stichophormis cornutella, n. sp. (PI. 75, fig. 9).

Shell slenderly conical, with nine annular strictures and six longitudinal divergent ribs, which
arise in the middle of the shell (from the sixth or seventh stricture), and are prolonged over the
wide mouth into six slender bristle-shaped feet, about half as long as the shell. The bases of the
feet are connected by arcades of lattice-work. All ten joints have nearly the same length and
regular hexagonal pores (in the first and second joints circular). Cephalis hemispherical, with a
very large curved horn, nearly half as long as the shell, and on one side decurrent to the fourth or
fifth joint.

Dimensions. — Length of the shell (with ten joints) 0'16, of each single joint about 0'016 ; basal
breadth 0'07.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

Subgenus 2. Stichophormiscus, Haeckel.

Definition. — Shell with nine prominent radial ribs, which are prolonged over the
mouth into nine (sometimes eight or ten) divergent free feet.

4. Stichophormis novena, n. sp. (PI. 79, fig. 9).

Shell slenderly conical, very similar to the preceding, but with eleven annular strictures and nine
divergent ribs, which arise from the tenth or eleventh stricture, and are prolonged over the wide
mouth into nine bristle-shaped feet, half as long as the shell. The length of the twelve joints
increases gradually; the tenth is twice as long as the sixth. Pores regular, circular. Cephalis

1456 THE VOYAGE OF H.M.S. CHALLENGER.

hemispherical, with a curved conical horn of twice the length. (In the somewhat mutilated specimen
figured, the horn and the nine feet were broken off, but were well preserved in another specimen,
found afterwards.)

Dimensions. — Length of the shell (with twelve joints) 0'22, eighth joint 0'02, fourth joint O'Ol ;
basal breadth 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

5. Stichophormis radiata, n. sp.

Shell slender, conical, with fourteen annular strictures, and nine radial ribs ; three primary ribs
arise from the third stricture, the other six (secondary) ribs from the ninth stricture ; all are pro-
longed over the mouth into nine slender bristle-shaped feet, about twice as long as one joint. All
joints have nearly the same length. Cephalis subspherical, with a straight, conical horn three times
the length. Pores regular, hexagonal. <

Dimensions. — Length of the shell (with fifteen joints) 0'24, of each joint, about 0'016 ; basal
breadth 012.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

Genus 637. Phormocampe, n. gen.

Definition. — S tichophormida (vel Stichocyrtida multiradiata aperta), with
conical or pyramidal shell, without lateral ribs. Mouth dilated, with a corona of terminal
feet.

The genus Phormocampe may be derived from the preceding Stichophormis by
loss of the lateral ribs, whilst the terminal feet remain. It bears therefore to the latter
the same relation that Calocyclas exhibits to Theophormis among the Tricyrtida.

Subgenus 1. Anthocorys, Haeckel, 1881, Prodromus, p. 437.

Definition. — Shell with three transverse strictures or annular septa, and with four
distinct joints.

1. Phormocampe campanula, n. sp. (PI. 77, fig. 13).

Anthocorys campanula, Haeckel, 1881, Prodromus et Atlas (loc. cit.).

Shell campanulate, with three internal, annular septa. Length of the four joints = 5:2:8:3.
Cephalis three-sided, pyramidal, slender, bearing a pyramidal horn of the same length, with three
dentate edges. Thorax very small, hemispherical. Third joint very large, campanulate. Fourth
joint of the same breadth, but only one-third as long. Pores subregular, circular. Peristome with a
coronal of twelve to fifteen conical, divergent feet, as long as the last joint.

1 Phormocampe— Latticed caterpillar ;

REPORT ON THE RADIOLARIA. 1457

Dimensions. — Length of the shell (with four joints) 018, breadth 009. Length of the single
joints, a 0'05, 6 O02, c 0-08, d 0'03.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Phormocampe lamprocyclas, n. sp. (PI. 77, fig. 16).

Shell conical, with three internal annular septa. Length of the four joints = 1:1:3:4.
Cephalis subspherical, as large as the thorax, with a stout, pyramidal horn of three times the length,
bearing at the apex a spinulate knob. The fourth joint is the broadest, and has large, circular,
hexagonally-framed pores, two to three times as broad as the circular pores of the three first
joints. Peristome with a double coronal of short, conical, divergent feet, nine on each coronal.

Dimensions. — Length of the shell (with four joints) 016, breadth Oil. Length of the single
joints, a 0'02, b 0-02, c O'Oo, d 0'07.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Phormocampe eucalyptra, n. sp. (PI. 77, fig. 14).

Shell flatly conical, somewhat broader than long, with four internal annular septa. The four
joints increase gradually in length and breadth. Pores subregular, hexagonal. Cephalis hemi-
spherical, with two small, divergent horns. Peristome with a coronal of thirty to forty short, conical,
divergent feet.

Dimensions. — Length of the shell 014, breadth 017. Length of the single joints, a 0'02,
b 0-03, c 0-04, d O05.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

5. Phormocampe metalis, n. sp.

•

Shell spiny, with three broad internal annular septa. Three of the four joints are nearly
equal in length, each being three times as long as the first. Cephalis subspherical, with a conical
horn of twice the length. The second and third joints are together nearly ellipsoidal, and are
not separated externally. The fourth joint is separated from them by a deep stricture, one and a
half times as broad, and flatly conical. Pores subregular, circular, hexagonally framed. Peristome
with a coronal of twenty to thirty strong, conical, divergent feet.

Dimensions. — Length of the shell 0'22, basal breadth 016. Length of the single joint, a 0-02,
b 0-06, c 0-06, d OD8.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

Subgenus 2. Gyrtocorys, Haeckel, 1881, Prodromus, p. 438.
Definition. — Shell with four or more transverse strictures, and five or more joints.

(ZOOL. CHALL. EXP. — PART XL. — 1886.) El 183

1458 THE VOYAGE OF H.M.S. CHALLENGEK.

5. Phormocampe mitra, n. sp.

Shell broadly campanulate, conical, about as broad as long, with five internal annular septa.
Length of the six joints gradually increasing. Cephalis flat, cap-shaped, with a short, bristle-
shaped, conical horn. Pores small and numerous, regular, hexagonal, with thin bars. Peristome
with a coronal of forty to fifty divergent, bristle-shaped feet, about as long as the last joint.

Dimensions. — Length of the shell (with six joints) 016, of the last joint 0'05 ; breadth 018.

Habitat. — North Pacific, Station 235 (off Japan), surface.

6. Phormocampe conus, n. sp.

Shell slenderly conical, three times as long as broad, with thirteen distinct strictures. Length
of the fourteen joints nearly equal Breadth gradually increasing towards the mouth. Cephalis
hemispherical, with a slender, conical, curved horn of three times the length. Pores small and
numerous, regular, circular. Peristome with a coronal of twenty to thirty slightly divergent, bristle-
shaped feet, twice as long as the last joint.

Dimensions. — Length of the shell (with fourteen joints) 0'22, of each joint (on an average)
0-016 ; basal breadth 0'08.

Habitat. — South Pacific, Station 297, surface.

Genus 638. Artophormis,i Haeckel, 1881, Prodromus, p. 438.

/

Definition. — S tichophormida (vel Stichocyrtida multiradiata aperta) with
ovate or spindle-shaped shell, bearing in its wall numerous lateral ribs, which are
prolonged into terminal feet. Mouth constricted.

The genus Artophormis and the following Cyrtojjhormis differ from the two
preceding genera in the ovate form of the shell, which tapers in breadth* towards
the constricted mouth. It differs from the similar Alacorys in the greater number
of the shell-joints, this being four or more.

1. Artophormis horrida, n. sp. (PI. 75, fig. 2).

Shell slenderly ovate, spiny, with three deep strictures, twice as long as broad. Length of the
four joints = 2:5:6:7. Whole surface covered with strong, conical spines. Six prominent,
longitudinal ribs, decurrent from the cephalis to the mouth, are armed with larger spines, which in
the upper joints are directed upwards, in the lower downwards. The six ribs are prolonged over
the constricted mouth into six stout, conical feet. Cephalis subspherical, with a conical horn and
some smaller spines. Pores circular, of very different sizes.

1 Artopkormis = Bread-basket ;

REPORT ON THE RADIOLAEJA. 1459

Dimensions. — Length of the shell (with four joints) 0'2, breadth Ol. Length of the single
joints, a 0'02, b 0'05, c 0'06, d 0'07.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

2. Artophormis costata, n. sp.

Shell spindle-shaped, rough, with six distinct strictures, three times as long as broad. The
length of the seven joints increases gradually ; the last joint is twice as long as the fifth. Six
prominent, radial ribs arise from the third stricture, and are prolonged into six slender, convergent,
conical feet, as long as the sixth joint. Cephalis hemispherical, with a pyramidal horn of twice
the length. Pores regular, circular.

Dimensions. — Length of the shell (with seven joints) 0'24, breadth 0'08. Length of the last
joint 0'05.

Habitat. — -South Pacific, Station 295, depth 1500 fathoms.

3. Artophormis barbadensis, Haeckel.

Calocyclas barbadensis, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66,
Taf. xviii. fig. 8.

Shell slenderly ovate, smooth, with three sharp strictures, twice as long as broad. Length of
the four joints = 1:2:3:2. Nine prominent longitudinal ribs arise from the third joint, and are
prolonged into nine slender, conical, little convergent feet. Cephalis hemispherical, with a conical
horn of the same length. Pores subregular, circular, twice as large in the third joint as in the
second ; the fourth joint bears above a circle of nine very large pores (alternate with the nine
ribs), and below two or three circles of smaller pores (eighteen to twenty-seven in the circum-
ference). Mouth somewhat constricted. The figure of Ehrenberg is incomplete, the horn of the
cephalis and the nine feet being broken off.

Dimensions. — Length of the shell (with four joints) 0'16, breadth 0'08. Length of the single
joints, a 0'02, b 0'04, c 0'06, d 0'04.

Habitat. — Fossil in Barbados.

Genus 639. Cyrtophormis,1 n. gen.

Definition. — S t i cho ph or mida (vel Stichocyrtida multiradiata aperta) with
ovate or spindle-shaped shell, without lateral ribs. Mouth constricted, with a corona
of terminal feet.

The genus Cyrtophormis may be derived from the preceding Artophormis by
reduction of the lateral ribs, whilst the terminal feet (as their free prolongations)
remain, and form a corona around the mouth. Sometimes also each constriction bears

1 Cyrtophormis = Plaited-baeket ; XI/JTO?,

1460 THE VOYAGE OF H.M.S. CHALLENGER.

a corona of spines. It corresponds to Calocyclas among the Tricyrtida and Anthocyrtis
among the Dicyrtida.

Subgenus 1. Cyrtophormium, Haeckel.

Definition. — Shell with six (sometimes five or seven) feet on the peristome
(three perradial alternate with three interradial).

1. Cyrtophormis armata, n. sp. (PL 78, fig. 17).

Shell spiny, spindle-shaped, with three annular septa. Length of the four joints = 3:4:5:6.
The third joint is the broadest, being twice as broad as the constricted mouth. Pores irregular,
roundish. Cephalis conical, armed with a bunch of strong, conical spines, and distinguished by
double-contoured pores. Peristome with six (sometimes five or seven) triangular, vertical, parallel,
or slightly divergent feet.

Dimensions. — Length of the shell (with four joints) 018, breadth 0'09. Length of the single
joints, a G'03, & 0'04, c 0'05, d 0'06.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Cyrtophormis ovata, n. sp.

Shell rough, ovate, very thick-walled, with three distinct strictures. Length of the four
joints — 1 : 1 : 2 : 3. The fourth joint is the broadest, inversely hemispherical, and three times as
broad as the constricted mouth. Pores regular, circular, hexagonally framed. Cephalis hemi-
spherical, with a pyramidal horn of the same length. Peristome with a coronal of six short,
conical, curved, outwardly convex teeth.

Dimensions. — Length of the shell (with four joints) 0'2, breadth 014. Length of the single
joints, a 0'02, b 003, c 0'06, d 0'0&.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

Subgenus 2. Cyrtophormiscus. Haeckel.

Definition. — Shell with nine (sometimes eight or ten) feet on the peristome
(three perradial alternate with six interradial).

3. Cyrtophormis cingulata, n. sp. (PI. 78, fig. 18).

Shell spiny, spindle-shaped, with three internal annular septa, and three external girdles of
spines. The second and third joints are of nearly equal length, twice as broad as the first, and
half as broad as the fourth joint. The third joint is the broadest, and twice as broad as the con-
stricted mouth. Pores subregular, circular. Cephalis hemispherical, with a large apical horn, and

REPORT ON THE RADIOLARIA. 1461

a coronal of six strong ascending spines. Peristoine beyond the stricture of the mouth somewhat
dilated, with nine triangular, divergent teeth (broken off in the specimen figured).

Dimensions. — Length of the shell (with four joints) 0'18, breadth 0'09. Length of the single
joints, a 0'02, I 0'04, c 0'04, d 0'08.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

4. Cyrtophormis aculeata, n. sp.

Shell spiny, slenderly ovate, with five distinct strictures, each with a girdle of spines. The three
middle joints are of nearly equal length, each half as long as the second, and one-third as long as
the sixth joint. The fifth joint is the broadest, twice as broad as the constricted mouth. Pores
regular, circular. Cephalis conical, with a bunch of strong, divergent spines. Peristome with nine
strong, conical, vertical, parallel teeth.

Dimensions. — Length of the shell (with six joints) 0P18, breadth 0'08. Length of the first joint
0-02, the second 0'04, the three following 0'02, the sixth 0'06.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

5. Cyrtophormis acutata, Haeckel.

Eucyrtidium acutatum, Stohr, 1880, Palasontogr., vol. zxvi. p. 105, Taf. iv. fig. 11.

Shell rough, spindle-shaped, with six annular strictures. The third, fourth, and seventh joints
are equal in length, three times as long as the first and the fifth joints. The fourth joint is the
broadest, four times as broad as the constricted mouth. Pores irregular, roundish. Cephalis small,
subspherical, with a short conical horn. Peristome with nine (?) irregular, triangular, little
convergent teeth.

Dimensions. — Length of the shell (with seven joints) 0'22, breadth Oil. Length of the third,
fourth, and seventh joints 0'04.

Habitat. — Fossil in Tertiary rocks of Sicily ; Grotte (Stohr).

Subgenus 3. Acanthocyrtis, Haeckel.
Definition. — Shell with numerous (twelve to twenty or more) terminal feet.

6. Cyrtophormis cylindrica, n. sp. (PL 77, fig. 17).

Shell rough, subcyliudrical, with three annular septa. The fourth cylindrical joint is four times
as long as the second and the third joints. These three joints are nearly equal in breadth. Pores
small and numerous, almost square, in regular, transverse rows ; two to three in the first joint, five to
six in the second and in the third, fourteen to sixteen in the fourth joint. Cephalis flat, cap-shaped,
with a short, pyramidal horn. Peristome half as broad as the shell, hyaline, with a coronal of
numerous, very delicate, vertical feet.

1462 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Length of the shell (with four joints) O2, breadth, O08. Length of the single
joints, a 0'02, I 0"03, c 0'03, d 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

7. Cyrtophormis corona, ru sp. (PL 77, fig. 15).

Shell smooth, conical, ovate, with three deep strictures, about twice as long as broad. The
fourth joint is the broadest, inflated, and three times as long as the second and the third joints.
Pores small and numerous, circular, in regular, transverse rows ; two in the first joint, four in the
second and third, and ten in the fourth joint. Cephalis hemispherical, with a stout, pyramidal horn.
Peristome two-thirds as broad as the fourth joint, with twelve to fifteen triangular, convergent teeth.

Dimensions. — Length of the shell (with four joints) 016, breadth 0'08. Length of the single
joints, a O'Ol, b 0'03, c 0'03, d 0'09.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

8. Cyrtophormis cornuta, n. sp. (PL 77, fig. 18).

Shell thorny, spindle-shaped, with three distinct strictures. Length of the four joints =
2:4:3:5. The third joint is the broadest. Pores circular, of different sizes, in the three first
joints double-contoured. Cephalis subspherical, with a large, conical horn of three times the
length. The fourth joint is inversely conical, three times as broad as the constricted mouth.
Peristome with a coronal of numerous (ten to twenty) irregular, thin, partly forked teeth.

Dimensions. — Length of the shell (with four joints) 014, breadth 0'07. Length of the single
joints, a 0'02, b 0'04, c 0'03, d 0'05.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

9. Cyrtophormis Jimbriata, Haeckel.

Lithocampe fimbriata, Stohr, 1880, Pataeontogr., vol. xxvi. p. 103, pi. iv. fig. 3.

Shell rough, spindle-shaped, with six annular septa. The fifth joint is the longest, twice as
long as each of the three preceding joints, and four times as long as the sixth. The fourth joint is
the broadest, three times as broad as the constricted mouth. Pores small, regular, circular.
Cephalis small, subspherical, with a small, conical horn (broken off in the specimen figured).
Peristome with an irregular, double coronal of ten to twenty vertical teeth.

Dimensions. — Length of the shell (with seven joints) 0'25, breadth 01. Length of the fifth
joint 0'06, of each of the three preceding 0~03.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; fossil in Sicily (Grotte, Caltanisetta).

10. Cyrtophormis turrita, n. sp.

Shell smooth, nearly conical, twice as long as broad, with twelve sharp strictures. The thirteen
joints increase gradually in length and breadth. The last joint is much longer than any of

REPORT ON THE RADIOLARIA. 1463

the others, twice as long as the eleventh, and twice as broad as the ninth joint. The constricted mouth
on its lower surface is only one-third as broad. Cephalis small, hemispherical, with a short, conical
horn. Peristome with a coronal of twenty to thirty delicate, partly confluent, vertical teeth.

Dimensions. — Length of the shell (with thirteen joints) 0'26, breadth 012.

Habitat. — South-Eastern Pacific, Station 299 (off Valparaiso), depth 2160 fathoms.

11. Cyrtophormis turricula, n. sp. (PL 75, fig. 5).

Shell smooth, slender, tower-shaped, with fourteen distinct strictures. The ten first joints are
nearly equal in length. The twelfth joint is the largest, three to four times as long as each of the
preceding, and broader than all the others, twice as broad as the suddenly constricted mouth. Pores
small and numerous, regular, circular, quincuncial. Cephalis small, subspherical, with a pyramidal
horn of three times the length. Peristome with a coronal of twenty to thirty very delicate, partly
confluent, short, vertical teeth.

Dimension^. — Length of the shell (with fifteen joints) 0'3, breadth 01. Length of the twelfth
joint 0-05.

Habitat. — South-Eastern Pacific, Station 298 (off Valparaiso), depth 2225 fathoms.

Subfamily 2. STICHOPH^NIDA, Haeckel, 1881, Prodromus, p. 439.

Definition. — P hormocampida with the terminal mouth of the shell fenestrated
(vel Stichocyrtida multiradiata clausa).

Genus 640. Artophcena,'1- Haeckel, 1881, Prodromus, p. 438.

Definition. — Stichophaenida (vel Stichocyrtida multiradiata clausa) with six
radial ribs or wings.

The genus Artophcena and the following genus Stichophcena represent together the
small subfamily of Stichophcenida, or of those Cyrtoidea in which the multiradiate
shell is composed of numerous (four or more) joints, and closed at the end by a lattice-
plate. The number of the lateral, solid, or latticed appendages is six in Artophcena,
nine in Stichophcena. They may have been derived either from the Stichophormida
by closure of the terminal mouth, or from the Stichoperida by intercalation of three
or six interradial appendages.

1. Artophcena cerostatica, n. sp. (PL 75, fig. 4).

Shell four-jointed, with three sharp strictures and internal septa. The fourth joint is sub-
spherical, longer than the three first joints together, and twice as broad as these. The second joint is

1 Artopluena = Bread-shell; oSjrof, q>a.hct..

1464 THE VOYAGE OF H.M.S. CHALLENGER.

twice as long as the first and the third, and armed with six divergent, stout, pyramidal, radial spines
or wings of the same length. Cephalis flat, cap-shaped, with an oblique pyramidal horn of twice
the length. Pores regular, circular, hexagonally framed.

Dimensions. — Length of the shell (with four joints) 0'18, breadth 012. Length of the single
joints, a 0'02, & 0'04, c 0'02, d O'l.

Habitat.— Central Pacific, Station 265, depth 2900 fathoms.

2. Artophcena senaria, n. sp.

Shell pear-shaped, with five distinct strictures. Length of the four middle joints little different.
The fifth joint is the broadest. From the first stricture there arise six radial ribs, which at the
fourth are prominent as six short, conical, divergent spines. The last joint is inversely hemi-
spherical, twice as long as the preceding. Cephalis hemispherical, with a conical horn of the same
length. Pores regular, circular.

Dimensions. — Length of the shell (with six joints) 0-14, breadth 0'09 ; of each joint 0'02, of the
last 0-04.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

3. Artophcena hexalatractus, n. sp.

Shell spindle-shaped, with three sharp strictures, and six triangular, latticed, divergent wings,
which arise from the collar stricture and descend along the two middle joints. Their terminal
points fall into the same plane as the basal end of the fourth inversely conical joint. Length of
the four joints = 1:2:4:2. Cephalis hemispherical, with a conical horn of the same length.
(Similar to Theophcena hexaptera, PI. 68, fig. 13, but with three distinct internal annular septa,
corresponding to the three external strictures.)

Dimensions. — Length of the shell (with four joints) 0'18, breadth 0'08. Length of the four
single joints, a 0'02, & 0'04, c 0'08, d 0'04.

Habitat. — South Pacific (off Juan Fernandez), Station 300, depth 1375 fathoms.

4. Artophcena hexapodiscus, n. sp.

Shell ovate, without external strictures, but with five internal annular septa. Length of the
six joints = 1:2:3:4:3:6. Cephalis hemispherical, with a stout conical horn of twice the
length. The last joint is the broadest, inversely hemispherical. From the fourth and fifth joints
arise six divergent ribs, which are prolonged over the fifth stricture into six triangular, divergent,
fenestrated feet, about as long as the last joint. Pores in the upper half of the shell regular,
circular, in the lower half irregular, roundish.

Dimensions. — Length of the shell (with six joints) 0'2, breadth 0'12. Length of the single
joints, a O'Olo, & 0'025, c 0'03, d 0'04, e 0'03,/0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

REPORT ON THE RADIOLARIA. 1465

Genus 641. Stichophcena,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichophsenida (vel Stichocyrtida multiradiata clausa) with nine
radial ribs or wings.

The genus Stichophcena differs from the preceding Artophcena in the typical number
of the radial lateral appendages, being nine in the former, six in the latter. Usually these
are simple ribs enclosed in the shell-wall, more rarely prominent wings.

Subgenus 1. Stichophcenidium, Haeckel.
Definition. — Last joint of the shell rounded, without basal spines.

1. Stichophcena ritteriana, n. sp. (PL 75, fig. 12).

Shell pear-shaped, twice as long as broad, with seven internal annular septa. The upper half is
slenderly conical, composed of seven joints of nearly equal length, gradually increasing in breadth.
The lower half is formed only by the eighth joint, which is very large, subglobose, inflated, and as
long as the seven other joints together. The spherical cephalis bears a conical horn of the same
length. From the thorax arise at equal distances nine radial ribs hi the form of thin, triangular
lamellae, which attain their greatest height in the sixth joint, and form nine elegant, denticulate
crests in the eighth joint. Pores small and numerous, subregular, circular. This beautiful species
is dedicated to my honourable friend, Dr. Paul von Bitter, the magnanimous philanthropist and
liberal protector of free science, who founded in the University of Jena the first professorial chair
of Darwinism and phylogeny.

Dimensions. — Length of the shell (with eight joints) 0'24, breadth 012. Length of each of the
first seven joints O'Olo ; diameter of the subspherical last joint O12.

Habitat. — South Pacific, Station 300 (off Juan Fernandez), depth 1375 fathoms.

2. Stichophcena darwiniana, n. sp.

Shell pear-shaped, twice as long as broad, with six distinct strictures. The last joint is the
broadest and twice as long as the sixth, three times as long as each of the five preceding joints.
The hemispherical cephalis bears a conical horn of twice the length. From the third joint arise
nine radial ribs, which reach the sixth joint, but are not developed in the last hemispherical joint.
Pores irregular, roundish.

Dimensions. — Length of the shell (with seven joints) 0'2, breadth O'l. Length of five first
joints, each Q'018 to 0'022, of the sixth 0'03, of the seventh joint 0'06.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

1 Stichoph(Bna = Row-shell; inixor, (fixina.

(ZOOL. CHALL. EXP. PABT XL. — 1886.) Rr 184

1466 THE VOYAGE OF H.M.S. CHALLENGED

3. Stichophcena gcetheana, n. sp.

Shell ovate, one and a half times as long as broad, rough, with five internal annular septa. The
six joints gradually increase in length and breadth. The last joint is the broadest, and half as long
as the five others together. The hemispherical cephalis bears a pyramidal horn of twice the length.
From the thorax arise nine radial ribs, which attain their greatest height in the fourth joint and
reach the fifth joint, but are not developed in the last ovate joint. Pores subregular, circular.

Dimensions. — Length of the shell (with six joints) 0'22, breadth 014. Length of the single
joints, a 0'02, b 0'025, c 003, d 0'035, e 0'04, / 0'7.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 2. Stichophcenoma, Haeckel.

Definition. — Last joint of the shell pointed, armed with a polar, basal spine, or a
bunch of spines.

4. Stichophcena nonaria, n. sp. (PI. 76, fig. 6).

Shell nearly spindle-shaped, with five or six distinct strictures. The third joint is the broadest
and longest, and twice as long as the second and the fifth joints. Along the second or third middle
joint (beginning from the second or third) descend nine prominent longitudinal ribs. Cephalis
hemispherical, with two short, conical, divergent horns. Last joint inversely conical, armed with
several strong, conical, divergent spines,

Dimensions. — Length of the shell (with seven joints) 0'23, of the third joint 0'05, of the last
0-04; breadth 01.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

5. Stichophcena novena, n. sp. (PL 76, fig. 7).

Shell nearly spindle-shaped, with eight or nine deep strictures. The third joint is the broadest,
campanulate, in its lower half with nine prominent ribs, which disappear beyond the third stricture.
The following joints are alternately longer and shorter, and decrease gradually in breadth. Thorax
hemispherical. Cephalis small, hemispherical, with a conical horn of the same length. Last
joint also hemispherical, scarcely larger than the cephalis, with a bunch of conical, divergent
spines.

Dimensions. — Length of the shell (with nine joints) 0'25, of the third joint 0'05, of the last 0'02;
breadth 01.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

REPORT ON THE RADIOLARIA. 1467

Family LXX. LITHOCAMPIDA, n. fam.

Artocorida et Artocapsida, Stichocorida et Stichocapsida, Haeckel, 1881, Prodromus, pp. 437-439.

Definition. — S tichocyrtida eradiata. (Cyrtoidea with an annulated
shell, divided by three or more transverse constrictions into four or more annular
joints, without radial apophyses.)

The family Lithocampida comprises those Cyrtoidea in which the
lattice-shell is composed of numerous (four to eight or more) annular joints, and bears
no radial apophyses. It may be divided into two subfamilies, differing in the shape
of the terminal mouth. This is a simple wide opening in the Stichocorida (and the
united Artocorida), closed by a lattice-plate in the Stichocapsida (and the allied
Artocapsida). The phylogenetic origin of the Lithocampida may be found in the
Theocyrtida.

The number of species of Lithocampida is very great, and amounts here to more
than one hundred and sixty, whilst the total number of Stichocyrtida is about two
hundred and forty. They represent, therefore, two-thirds of the whole group, whilst
one-third is composed of the Podocampida and Phormocampida. Ehrenberg has
already described between forty and fifty species in his genera Eucyrtidium and Litho-
campe; the majority of these were fossils from Barbados.

This large number of species may be easily increased by accurate researches on the
great masses of Lithocampida, which are found in the Radiolarian ooze of the
Challenger, and as fossils in Barbados. The variety in the number, size, and proportion
of the shell-joints and of the lattice-pores is very great, and permits us to distinguish a
far greater number of species than are here described. Many species are cosmopolitan,
and belong to the most common forms of Radiolaria.

This large number of species requires to be disposed in different genera, but
the distinction of these latter is a rather difficult task, since the exterior of the shell, as
well as its internal structure, offers no striking differences (compare Pis. 78 to 80). In
my Monograph (1862, pp. 312 to 319) I have already pointed out the difficulty of
distinguishing between Lithocampe and Eucyrtidium. The general form of the shell
exhibits a continuous series of transformations, from a flat, conical, or nearly discoidal
form, through cylindrical to ovate, or spindle-shaped shells, the wide open terminal
mouth becoming more or less constricted, and finally (in the Stichocapsida) closed.
The absence .or presence of an apical horn may further serve for the distinction of
genera. A peculiar small group is represented by the Spirocampida (Spirocyrtis,
Spirocampe, PL 76, figs. 11 to 17), the transverse latticed girdles separating the single
joints, which are usually parallel and horizontal, becoming here partly connected, so
that they form a descending spiral.

1468

THE VOYAGE OF H.M.S. CHALLENGER.

Synopsis of the Genera of Lithocampida.

Conical, gradu- J

With horn, .

642. Lithostrobus.

Shell conical

ally dilated. |

No horn,

643. Dictyomitra.

or cylindrical
Mouth of the
last joint wide "

Conical above, (
cylindrical 1

V>plnw

With horn, .

644. Stichocorys.

All annular

open, not dis-

uciu w»

I. Subfamily

septa or
transverse
strictures of
the shell

tinctly con-
stricted.

Cylindrical or (
subcylin- <
dricaL (

With horn, .
No horn,

645. Artostrobus.
646. Lithomitra.

Stichocorida.
Terminal mouth .
of the last shell-

separated,
parallel, not
connected

Cephalis with J

Last joint not
tubular, .

647. Eucyrtidium.

joint a simple
wide opening.

by a spiral
line.

Shell ovate or
spindle-shaped.

a horn.

I

Last joint a long
tube,

648. Eusyringiurn.

Mouth of the
last joint con-
stricted.

Cephalis with- J

Cephalis with
tube.

649. Siphocampe.

out horn. |

Cephalis without

I

tube,

650. Lithocampe.

Annular septa or transverse strictures of the (

With horn, .

651. Spiroeyrtig.

shell all or partly obliquely descending and <

connected spirally.

No horn,

652. Spirocampe.

II. Subfamily
Stichocapsida.

Last joint rounded, without a vertical basal 1

With horn, .

653. Cyrtocapsa.

Terminal mouth ;

spine.

No horn,

654. Stichocapsa.

closed by a

lattice-plate.

Last joint conical, pointed, with a vertical, basal f
spine. \

Cephalis with horn,

655. Artocapsa.

Subfamily 1. STICHOCORIDA, Haeckel, 1881, Prodromus, p. 438.

Definition. — L ithocampida with the terminal mouth of the shell open (vel
Stichocyrtida eradiata aperta).

Genus 642. Lithostrobus,1 Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.

Definition. — Stichocorida (vel Stichocyrtida eradiata aperta), with conical
shell, gradually dilated towards the wide open mouth. Cephalis with a horn.

The genus Lithostrobus is probably the most primitive among the Lithocampida,
and comprises those forms of this family in which the slender, conical shell is gradually
dilated towards the wide, terminal mouth, each joint being broader than the preceding.

1 Lithostrobus = Cone of silex; X/0of, orjo'/Sof.

REPORT ON THE RADIOLARIA. 1469

It may be derived from Theoconus by increase in the number of the joints. Some species
are distinguished by a curved axis, which gives them a horn -like appearance; these may
be separated as a peculiar genus, Cornustrobus.

Subgenus 1. Conostrobus, Haeckel.

Definition. — Shell regularly conical, with straight axis ; all joints nearly equal in
length, gradually increasing in breadth.

1. Lithostrobus monostichus, n. sp.

Shell slenderly conical, smooth, with straight axis, and eight to ten deep strictures. All joints
nearly of the same length, gradually increasing in breadth ; the eighth joint twice as broad as the
fourth. In each joint only a single transverse series of small, circular, regular pores. Horn of
the cephalis conical, straight, of twice the length. (Similar to Lithostrobus tetrastichus, PI. 80,
fig. 6, but in each joint there is only a single series of pores.)

Dimensions. — Length of the shell (with ten joints) 0'2, of each joint 0'02 ; breadth of the
fourth joint 0'03, of the eight 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Liihostrobus distichus, n. sp.

Shell conical, papillate, with straight axis, and four to six deep strictures. All joints nearly of
the same length, the fifth twice as broad as the second. In each joint two transverse rows of large,
circular pores. Horn of the cephalis stout, straight, conical, of the same length.

Dimensions. — Length of the shell (with six joints) 0-18, of each joint 0'03 ; breadth of the
second joint 0'04, of the fifth 0'08.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Lithostrobus tristichus, Haeckel.

Lithostrobus cuspidatus, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.
Eucyrtidium cuspidatum, Bailey, 1856, Amer. Journ. Sci. and Arts, vol. xxii. p. 5, pi. i. fig. 12.

Shell slenderly conical, smooth, with straight axis, and eight to ten deep strictures. All joints
nearly of the same length, the eighth joint twice as broad as the third. In each joint three trans-
verse rows of pores. Horn of the cephalis bristle-shaped, strongly curved, about as long as the
shell. (Ehrenberg confounds this species with Lithostrobus cuspidatus).

Dimensions. — Length of the shell (with eight joints) 016, of each joint 0'02 ; breadth of the
fourth joint 0'04, of the eighth O'OS.

Habitat. — North Pacific, Kamtschatka (Bailey); Station 241, depth 2300 fathoms.

1470 THE VOYAGE OF H.M.S. CHALLENGER.

4. Lithostrobus tetrastichus, n. sp. (PI. 80, fig. 6).

Shell slenderly conical, smooth, with straight axis and six to eight deep strictures. All joints
nearly of the same length, the eighth joint twice as broad as the second. In each joint four trans-
verse rows of regular, circular pores with very thin bars. Horn of the cephalis conical, strong,
curved, about as long as two joints.

Dimensions. — Length of the shell (with eight joints) 012, of each joint 0'015 ; breadth of the
second joint 0'02, of the eighth 0'04.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Lithostrobus pentastichus, n. sp.

Shell slenderly conical, smooth, with straight axis, and six to eight slight strictures. All joints
nearly of the same length, the sixth twice as broad as the third. In each joint five transverse
rows of small circular pores. Horn of the cephalis pyramidal, of twice the length. (Similar to
Eucyrtidium cienkowskii, PL 80, fig. 9, but regularly conical, with all the joints equal in length.)

Dimensions. — Length of the shell (with eight joints) 0'2, of each joint 0'025 ; breadth of the
third joint 0'04, of the sixth 0'08.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

6. Lithostrobus hexastichus, n. sp. (PL 80, fig. 15).

Shell campanulate-conical, smooth, with straight axis, and six to eight slight strictures. All
joints nearly of the same length, the sixth joint twice as broad as the second. In each joint six
transverse rows of subregular, hexagonal pores, with thin bars. Horn of the cephalis conical,
straight, of about the same length. (The specimen figured is a somewhat irregular one ; other
specimens found afterwards were perfectly conical and regular, with joints of equal length).

Dimensions. — Length of the shell (with six joints) 0'16, of each joint 0'027.

Habitat. — Central Pacific, Station 270 to 274, depth 2350 to 2925 fathoms.

Subgenus 2. Cornustrobus, Haeckel.

Definition. — Shell horn-shaped, conical, with curved axis ; all joints nearly equal in
length, gradually increasing in breadth.

7. Lithostrobus cyrtoceras, n. sp. (PL 80, fig. 2).

Shell horn-shaped, conical, with curved axis, smooth, with six to eight deep strictures. All
joints nearly of the same length, gradually increasing in breadth ; the sixth joint twice as broad as
the second. In each joitft about four transverse series of regular circular pores. Horn of the
cephalis conical, slightly curved, of the same length.

REPORT ON THE RADIOLARIA. 1471

Dimensions. — Length of the curved axis of the shell (with eight joints) 0'24, length of each
joint 0'03 ; breadth of the second joint 0'04, of the sixth 0'08.
Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

8. Lithostrobus leptoceras, n. sp.

Shell horn-shaped, slenderly conical, with curved axis (like a quadrant of a circle), smooth, with
twelve to fourteen slight strictures. All joints nearly of the same length, the tenth twice as broad
as the second. In each joint only a single transverse row of small circular pores. Horn of the
cephalis curved, bristle-shaped, half as long as the shell.

Dimensions. — Length of the curved axis of the shell (with twelve joints) 018, length of each
joint 015 ; breadth of the second joint 0'02, of the tenth 0'04.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

9. Lithostrobus caloceras, n. sp. (PL 80, fig. 4).

Shell horn-shaped, conical, with curved axis, smooth, with six to eight deep strictures. All
joints nearly of the same length, the sixth twice as broad as the third. On each joint a single
circle of very large roundish pores, separated by two to four series of smaller pores. Horn of the
cephalis conical, curved, of twice the length.

Dimensions — Length of the curved axis of the shell (with six joints) 012, length of each joint
0-02 ; breadth of the third joint 0'04, of the sixth 0'08.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

10. Lithostrobus macroceras, n. sp.

Shell horn-shaped, slenderly conical, with curved, nearly semicircular axis, without external
strictures, but with twelve to twenty internal septal rings. All joints nearly of the same length,
the twelfth twice as broad as the third. On each joint three to four transverse rows of subregular,
small, hexagonal pores. Horn of the cephalis conical, curved, of twice the length.

Dimensions. — Length of the curved axis of the shell (with sixteen joints) 0-32, length of each
joint 0-02 ; breadth of the third joint 0'02, of the twelfth 0'04.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Subgenus 3. Cyrtostrobus, Haeckel.

»
Definition — Shell conical (often more campanulate or irregular), with straight axis ;

joints of different lengths. Cephalis not lobate.

1472 THE VOYAGE OF H.M.S. CHALLENGER.

11. Lithostrobus conulus, n. sp. (PI. 80, fig. l).

Shell slenderly conical, smooth, with straight axis, and seven to ten distinct strictures. Joints of
different lengths ; the fourth and fifth about twice as long as the preceding and following joints, the
former with four to five, the latter with two to three transverse rows of large irregular pores ; the
seventh joint twice as broad as the third. Horn of the cephalis short, pyramidal.

Dimensions. — Length of the shell (with eight joints) 014, length of the fifth joint 0'03 ;
breadth 0'06.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

12. Lithostrobus picus, Biitschli.

Lithostrobus picus, Biitschli, 1882, Zeitschr. f. wiss. ZooL, vol. xxxvi. p. 529.
Euc,yrtidium picus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi.
fig. 1.

Shell slenderly conical, smooth, with straight axis, and six to eight slight strictures. Joints of
different lengths, the second twice as long as each of the three following, and four times as long as
each of the last joints; the sixth joint one and a-half times as broad as the second. Small circular
pores in regular transverse rows; six rows in the first and the second, three rows in the third, fourth,
and fifth, a single row in each of the last joints. Horn of the cephalis cylindrical, half as long as
the shell.

Dimensions. — Length of the shell (with eight joints) 012, length of the second joint 0'03 ;
breadth 0'04.

Habitat. — Fossil in Barbados.

13. Lithostrobus argus, Biitschli.

Lithostrobus argus, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi p. 529.

Eucyrtidium argus, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. ix. fig. 1.

Shell conical, thorny, with straight axis, and five to seven slight strictures. Joints of different
lengths, each of the three first twice as long as each of the following. Pores large, roundish, in trans-
verse rows ; three rows in the first and the second joints (which in the figure of Ehrenberg are not
separated), two rows in the third joint, a single row in each of the following joints. Horn of the
cephalis large, conical, curved, half as long as the shell.

Dimensions. — Length of the shell (with seven joints) 0'2, length of the fourth joint (and each
following) 0-02 ; breadth 01.

Habitat. — Fossil in Barbados.

14. Lithostrobus acuminatus, Haeckel.

Eucyrtidium acuminatum, Bury, 1862, Polycystins of Barbados, pi. i. fig- 1-

Shell slenderly conical, smooth, with straight axis, and four to six deep strictures. Joints gradu-
ally increasing in length. Pores in regular, transverse rows, commonly three rows in the first, four

REPORT ON THE RADIOLARIA. 1473

in the second, five in the third, six in the fourth, seven in the fifth, &c. (sometimes the increase of
the number is more or less irregular). Horn of the cephalis strong, conical, straight, about as long
as the fourth or sixth joint.

Dimensions. — Length of the shell (with six joints) 0'2 ; length of the fourth joint 0'04, breadth
0-06.

Habitat. — Fossil in Barbados.

15. Lithostrobus cuspidatus, Haeckel.

Eucyrtidium cuspidatum, Ehrenberg, 1872, Abhandl d. k. Akad. d. Wiss. Berlin, p. 291, Taf. ii.
fig. 15.

Shell, slender, conical, smooth, with straight axis, and ten to twelve distinct strictures. Joints
gradually increasing slightly in length, the tenth twice as long as the third. Pores circular, in regular
transverse rows ; commonly two rows in the first, three in the second, four in the third, seven in
the eighth and following joints. Horn of the cephalis long, bristle-shaped, curved. This species
called Eucyrtidium cuspidatum by Ehrenberg, differs from Lithostrobus tristichus (compare above), to
which Bailey had given the same name.

Dimensions. — Length of the shell (with ten joints) 0'2 ; length of the tenth joint 0'03, breadth
0-06.

Habitat. — North Atlantic (Greenland, Ehrenberg); Station 348, depth 2450 fathoms.

16. Lithostrobus cornutella, Biitschli.

Liihostrdbus cornutella, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.
Eucyrtidium cornutella, Ehrenberg, 1872, Abhandl d. k. Akad. d. Wiss. Berlin, p. 291, Taf. ii.
fig. 14.

Shell slender, conical, smooth, with straight axis, and seven to nine slight strictures. Joints
gradually increasing slightly in length, the sixth or seventh about twice as long as the third. Pores
circular, in regular transverse rows ; two or three in the three or four first joints, three or four in
the following, four or five in the last joints. Horn of the cephalis thin, bristle-shaped, curved.

Dimensions. — Length of the shell (with eight joints) 01 ; length of the eighth joint 0-01, breadth
0-04.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific ; many stations, surface.

17. Lithostrobus tornatus, Haeckel.

Eucyrtidium tornatum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 292, Taf. ix.
fig. 20.

Shell campanulate-conical, smooth, with straight axis, and four to six deep strictures. Joints
broad, gradually increasing in length, the fifth twice as long as the second. Pores small, circular,
in regular transverse rows ; in the second and third joints three or four rows, in the fifth seven rows,
&c. Horn of the cephalis small, double or forked.

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 185

1474 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Length of the shell (with five joints) 01 ; length of the fifth joint 0'04, breadth
0-08.

Habitat. — Indian Ocean, Zanzibar, depth 2200 fathoms (Pullen).

18. Lithostrobus seriatus, n. sp. (PI. 79, fig. 15).

%

Shell slender, conical, smooth, with straight axis, and four or five deep strictures. Joints little
different in length, increasing towards the inflated last joint, which is twice as long as the pre-
ceding. On each joint four or five transverse rows of small circular pores. Horn small, bristle-
shaped, oblique. This common species is rather variable.

Dimensions. — Length of the shell (with five joints) 014 ; length of the fifth joint 0'05, breadth
0-06.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

19. Lithostrobus cornutus, n. sp. (PI. 77, fig. 6).

Shell slender, conical, subcampanulate, smooth, with three or four deep strictures. Joints of
different lengths, the third and the fourth twice as long as the second, four times as long as the
first. Transverse rows of small circular pores ; three in the first joint, five in the second, eight in
the third and in the fourth. Horn large, pyramidal, about as long as the third joint.

Dimensions. — Length of the shell (with four joints) 012 ; length of the third joint 0'04, breadth
0-06.

Habitat. — Central Pacific, Station 265 to 268, depth 2700 to 2900 fathoms.

20. Lithostrobus microporus, Biitschli.

Lithostrobus microporus, Biitsclili, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.
Eucyrtidium microporum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291, Taf.
xi. fig. 20.

Shell slender, conical, smooth, very similar to the preceding species, differs mainly in the more
slender form and the smaller pores. The first joint has four, the second eight, the third ten trans-
verse rows of pores. Horn conical, as long as the cephalis. The third joint in this and the pre-
ceding species is campanulate, and large.

Dimensions. — Length of the shell (with four joints) Oil ; length of the third joint 0'05, breadth
0-04.

Habitat. — Fossil in Barbados.

21. Lithostrobus quadratus, n. sp.

Shell broad, conical, smooth, with straight axis, and six to eight deep strictures. Joints of
different lengths, usually alternately longer and shorter. The seventh joint five times as broad
as long, twice as long as the sixth and the fourth ; six transverse rows of pores in the seventh, three

REPORT ON THE RADIOLARIA. 1475

in the sixth joint. Horn small, conical. This species differs from all others in the subregular
square form of the small pores.

Dimensions. — Length of the shell (with seven joints) 0'15 ; length of the seventh joint 0'024,
breadth 012.

Habitat — Central Pacific, Station 27l to 274, depth 2350 to 2750 fathoms.

22. Lithostrobus hexagonalis, n. sp. (PI. 79, fig. 20).

Shell broad, conical, smooth, with straight axis, and five to eight prominent girdles between six
and nine constricted broad joints. The first and the third joints are half as long as the second, the
fourth, and each of the following joints. The sixth joint is five times as broad as long. Pores sub-
regular, hexagonal, in regular transverse rows ; three to four rows in the first and the second joints,
six to eight in the third, the fourth, and each following joint. Cephalis with some small spines,
and a larger, oblique, curved horn.

Dimensions. — Length of the shell (with six joints) 0'2 ; length of the sixth joint 0'04, breadth
0-2.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subgenus 4. Botryostrobus, Haeckel.

Definition. — Shell conical, with straight axis, joints of different lengths. Cephalis
lobate, with some irregular constrictions. (Perhaps derived from Botryodea?).

23. Lithostrobus botryocyrtis, n. sp. (PI. 79, figs. 18, 19).

Shell slender, conical, smooth, with straight axis, and three deep strictures. Joints of different
lengths. The length of the fourth joint equals two-thirds of its breadth, and of the length of the
three preceding joints together. Each of the latter bears three transverse rows of small, quadrangular
pores, the fourth joint has six rows. The cephalis is irregularly lobate, with four to six prominent
lobes, and two small divergent horns (fig. 19).

Dimensions. — Length of the shell (with four joints) O'l ; length of the fourth joint 0'04,
breadth 0'06.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

24. Lithostrobus lithobotrys, n. sp. (PI. 79, fig. 17).

Shell slender, conical, smooth, with straight axis, and four deep strictures. Joints of different
lengths, gradually increasing towards the mouth, the length of the fifth joint equals half its breadth,
and one-third of the length of the whole shell. The single joints bear each four or five transverse
rows of small, roundish pores. Cephalis irregularly lobate, with four to six prominent lobes, and
the same number of small, conical horns.

1476 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions.- — Length of the shell (with five joints) 012 ; length of the fifth joint 0-04,
breadth 0'08.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 643. Dictyomitra,1 Zittel, 1876, Zeitschr. d. deutsch. geol. Gesellsch., p. 80.

Definition. — S tichocorida (vel Stichocyrtida eradiata aperta), with conical
shell gradually dilated towards the wide open month. Cephalis without horn.

The genus Dictyomitra agrees with the preceding Lithostrobus in the slender,
conical form of the multiarticulate shell, but differs from it in the absence of a horn on
the cephalis ; the horn is here completely lost.

Subgenus 1. Dictyomitrella, Haeckel.
Definition, — Shell smooth, with joints nearly equal in length.

1. Dictyomitra articulata, Haeckel.

Eucyrtidium articulatum, Ehrenberg, 1875, Abhaudl. d. k. Akad. d. "VViss. Berlin, p. 70,
Taf. XL figs. 2, 3.

Shell slender, conical, smooth, with six to eight deep strictures. All joints nearly equal in
length, gradually increasing in breadth, the eighth four times as broad as long, and twice as broad
as the fourth joint. In each joint three to four transverse series of small, regular, circular pores.

Dimensions. — Length of the shell (with eight joints) 0'12, of each joint O'OIS ; breadth of the
fourth joint 0'04, of the eighth joint '0'08.

Habitat. — Fossil in Barbados.

2. Dictyomitra macilenta, Haeckel.

Eucyrtidium macilentum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291,
Taf. vii. fig. 15.

Shell slender, conical, smooth, with five to seven deep strictures. All joints nearly equal in
length, gradually increasing in breadth, the sixth joint three times as broad as long, and twice as
broad as the second. In each joint only two transverse series of small, regular, circular pores.

Dimensions. — Length of the shell (with seven joints) 0'08, of each joint 0'012 ; breadth of the
sixth joint 0'036, of the second O'OIS.

Habitat. — Western Tropical Pacific, Stations 200 to 225, in various depths.

1 Dictyomitra, — Net-cap; S/XTBO*,

REPORT ON THE RADIOLARIA. 1477

3. Dictyomitra conica, n. sp.

Shell widely conical, with six to eight prominent strictures. All joints nearly equal in length,
gradually increasing in breadth, the eighth five times as broad as long, and twice as broad as the
third. In each joint three to four transverse rows of regular, hexagonal pores. (Similar to
Lithostrobus hexagonalis, PI. 79, fig. 20, but more slender, and without cephalic horn.)

Dimensions. — Length of the shell (with seven joints) 0'16, of each joint 0'022 ; breadth of the
sixth 0-08.

Habitat.— South Pacific, Station 295, depth 1500 fathoms.

Subgenus 2. Dictyomitrissa, Haeckel.
Definition. — Shell smooth, with joints of very different lengths.

4. Dictyomitra polypora, Zittel.

Dictyomitra polypora, Zittel, 1876, Zeitschr. d. deutsch, geol. Gesellsch., p. 80, Taf. ii. fig. 1.

Shell slender, conical, rough, with six to nine deep strictures. Breadth and length of the joints
gradually increasing, so that the eighth joint is twice as long and broad as the third. Pores regular,
circular, in transverse rows, four rows in each joint, in the last joint five to six rows.

Dimensions. — Length of the shell (with eight joints) 0'24 ; length of the eighth joint 0'04,
breadth 01 ; length of the third joint 0'02, breadth 0'05.

Habitat. — Fossil in secondary rocks of Northern Germany (chalk of Brunswick, &c.), Zittel.

5. Dictyomitra eurythorax, n. sp. (PI. 77, fig. 4).

Lithocampium eurythorax, Haeckel, 1881, Prodromus, p. 437, et Atlas, pL Ixxvii fig. 4.

Shell campanulate, conical, rough, with three deep strictures. Cephalis small, hemispherical.
Thorax large, inflated, hemispherical, with six transverse rows of pores. Abdomen with two broader
joints, together as long as the thorax, each with three to four rows of pores.

Dimensions. — Length of the shell (with four joints) 0'14, of the thorax 0'06 ; breadth of the
thorax 0'08, of the, last joint O'l.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

6. Dictyomitra microcephala , Haeckel.

Eucyrtidium microcephalwn, Ehrenberg, 1858, Monatsber d. k. preuss. Akad. d. Wiss. Berlin,
1>. 32; AbhandL d. k. Akad. d, Wiss. Berlin, 1872, p. 291, Taf. xi. fig. 24.

Shell broadly conical, smooth, with six to eight distinct strictures. -Breadth of the joints gradu-
ally increasing, length unequal. The three first joints short, only one-half or one-third as long as

1478 THE VOYAGE OF H.M.S. CHALLENGER.

each of the following joints ; in each of the former three to four transverse rows, in each of the
latter six to eight transverse rows of small, regular, circular pores.

Dimensions. — Length of the shell (with six joints) 0'09, of the three first joints 0'03, of the three
.following 0'06; breadth of the sixth joint 0'08, of the fourth 0'04

Habitat. — Mediterranean (Candia) Spratt, depth 1620 fathoms.

7. Dictyomitra demersissima, Haeckel.

Eucyrtidium demersissimum, Ehreiiberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 291,
Taf. vii. fig. 11.

Shell slender, conical, smooth, with four internal septal rings (without external strictures).
Breadth of the five joints gradually increasing, length unequal ; the third joint the longest, twice as
long as the second, and longer than any of the following. Pores very small and numerous, in longi-
tudinal rows.

Dimensions. — Length of the shell (with five joints) 0'09, of the second joint O'OIS, of the third
0'03; breadth of the second joint O03, of the third 0'05.

Habitat. — Tropical Pacific, Philippine Sea, depth 3300 fathoms.

Subgenus 3. Dictyomitroma, Haeckel.

Definition — Shell with longitudinal ribs and furrows between them, with joints of
different lengths.

8. Dictyomitra costata, n. sp.

Shell slender, conical, with prominent longitudinal ribs, and six to eight deep strictures. Length
of the majority of joints nearly equal, the two or three first joints shorter, the last a little longer.
In each joint only a single transverse series of pores at the distal end (one pore in each furrow).
(Similar to Siphocampe tubulosa, PL 79> fig. 13, but conical, and without cephalic tube.)

Dimensions. — Length of the shell (with eight joints) 016, of each middle joint 0'03, of the first
0-02; breadth of the last joint 0'06.

Habitat. — Central Pacific, Station 295, depth 1500 fathoms.

9. Dictyomitra multicostata, Zittel.

Dictyomitra multicostata, Zittel, 1876, Zeitschr. d. deutsch. geol. Gesellscb., p. 81, Taf. ii.
figs. 2-4.

Shell slender, conical, with prominent longitudinal ribs, and eight to ten deep strictures. Length
and breadth of the joints gradually increasing, the eighth joint twice as long and broad as the fourth
joint. Pores regular, circular, one series in each longitudinal furrow, three to four pores on each
joint.

REPORT ON THE RADIOLARIA. 1479

Dimensions. — Length of the shell (with eight joints) 0'2, of the fourth joint 0'02, of the eighth
joint 0-04; breadth of the fourth joint 0'04, of the eighth 0'08.

Habitat. — Fossil in secondary rocks of North Germany (chalk of Brunswick, &c.), Zittel.

Genus 644. Stichocorys,1 Haeckel, 1881, Prodromus, p. 438 (sensu emendato).

Definition. — S tichoeorida (vel Stichocyrtida eradiata aperta) with a middle
constriction of the shell, the upper half of which is conical, the lower cylindrical. Mouth
truncate. Cephalis with a horn.

The genus Stichocorys is intermediate between the two preceding and the two
following genera; the upper half of the shell with the three first joints is conical, the lower
half with the fourth and the following joints cylindrical, of equal breadth. The third joint
of the shell (or the abdomen of Theoconus) is constantly the largest, being broader than
all the other joints. Stichocorys is a very common and characteristic form, and may
be derived from Theoconus by development of a post-abdomen.

1. Stichocorys wolffii, n. sp. (PI. 80, fig. 10).

Shell in the upper half (with three joints) thorny, in the lower half (with two joints) smooth.
Pores of the former double-contoured, in subregular, transverse rows. Pores of the latter smaller,
simple, scarcely scattered. Cephalis with a pyramidal horn of the same length. Thorax with pro-
minent, longitudinal divergent ribs. Dedicated to Caspar Friedrich Wolff (Halle, 1759).

Dimensions. — Length of the shell (with five joints) 016; breadth of the third joint 0'08, of the
fourth 0'05.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Stichocorys pander i, n. sp. (PL 80, fig. 7).

Shell in the upper conical half (with three joints) spiny, in the lower subcylindrical half (with
three joints) smooth. Pores small, circular, irregularly scattered, simple. Cephalis with a conical
horn of the same length. No longitudinal ribs. Dedicated to Christian Pander (Wiirzburg, 1817.)

Dimensions. — Length of the shell (with six joints) 018; breadth of the third joint 0'08, of the
fourth 0'05.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Stichocorys baerii, n. sp. (PI. 80, fig. 8).

Shell in the upper conical half (with three joints) spiny, in the lower cylindrical half (with three
joints) sulcate, with prominent longitudinal ribs, alternating with longitudinal rows of small pores.

1 Stichocorys - Row-helmet ;

1480 THE VOYAGE OF H.M.S. CHALLENGER.

Pores of the upper half smaller, quincuncially disposed. Cephalis with a stout pyramidal horn of
the same length. Dedicated to Carl Ernst Baer (Konigsberg, 1828).

Dimensions. — Length of the shell (with six joints) 0'2 ; breadth of the third joint 0'09, of the
fourth 0-07.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Stichocorys okenii, n. sp. (PL 80, fig. 5).

Shell smooth, without spines or ribs; the upper conical half (with three joints) about the
same length as the lower subcylindrical half (witli three joints). Pores subregular, circular, in the
inflated third joint twice as large as in the five other joints. At the lumbar stricture (between
the second and third joints) a coronal of nine very large pores. Cephalis with a curved horn of half
the length. Dedicated to Lorenz Oken (Jena, 1806).

Dimensions. — Length of the shell (with six joints) 0-2; breadth of the third joint 0~09, of the
fourth 0-07.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Stichocorys huschkei, n. sp. (PI. 80, fig. 3).

Shell in the upper conical half (with three joints) thorny, in the lower cylindrical half (with
five joints) smooth, roundish. Pores irregularly scattered, always double-contoured, in the second
joint three times as large as in the third. At the third stricture (between the third and fourth
joints) a coronal of larger pores. Cephalis with a small, conical horn of half the length. No
longitudinal ribs. Dedicated to Emil Huschke (Jena, 1832).

Dimensions. — Length of the shell (with eight joints) 0'18 ; breadth of the third joint 0'08, of the
fourth joint 0'07.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

6. Stichocorys rathkei, n. sp.

Shell spiny, everywhere covered with short conical spines. The upper conical part of the
shell (with three joints) half as long as the lower cylindrical part (with six joints). Pores
irregular, roundish, in the thorax twice to three times as large as in the eight other joints. Cephalis
with a pyramidal horn of the same length. No longitudinal ribs. Dedicated to Heinrich
Kathke (Konigsberg, 1839).

Dimensions. — Length of the shell (with nine joints) 0-24 ; breadth of the third joint 0'08, of the
fourth joint 0'06.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

7. Stichocorys millleri, n. sp.

Shell in the upper conical part (with three joints) spiny, in the lower cylindrical part (with
seven joints) smooth. Pores in the former irregularly scattered, roundish, in the latter circular,

REPORT ON THE RADIOLARIA. 1481

regularly disposed in longitudinal series, alternate, with prominent ribs. The upper conical part of
the shell is about half as long as the lower cylindrical part. Cephalis with a large, pyramidal horn
of three times the length. Dedicated to Johannes Miiller (Berlin, 1858).

Dimensions. — Length of the shell (with ten joints) 0-22 ; breadth of the third joint 0'09, of the
fourth joint 0'06.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

Genus 645. Artostrobus, n. gen.

Definition. — S tichocorida (vel Stichocyrtida eradiata aperta) with cylindrical
shell, the upper pole of which is rounded, the lower truncate. Cephalis with a horn.

The genus Artostrobus and the following Dictyomitra differ from all the other
Stichocorida in the cylindrical or nearly cylindrical form of the shell, all the joints of
which are nearly equal in breadth, and are very short, often with a single transverse
row of pores only. The first joint or cephalis is usually different from the following,
often hemispherical or cap-shaped joints. The last joint is truncate, and has a wide
open mouth. Since the constrictions between the single joints are often very slight,
some species are very similar to the Dicyrtide Sethocorys.

Subgenus 1. Artostrobulus, Haeckel.

Definition. — A single transverse row of small, circular pores on each joint.
(Sometimes on the uppermost joints two or three rows.)

1. Artostrobus annulatus, Haeckel.

Cornutella annulata, Bailey, 1856, Amer. Journ. Sci. and Arts, voL xxii. pL i. fig. 5a, 5b.
Eucyrtidium annulatum, Haeckel, 1862, Monogr. d. Radio!, p. 327.

Shell slender, cylindrical, smooth, without external strictures, but with ten to twenty internal
annular septa. On each joint only a single transverse row of small pores. Cephalis hemi-
spherical, with a single or double small horn. Each joint about four times as broad as long.

Dimensions. — Length of the shell (with twenty joints) 0'2 ; length of each joint O'Ol, breadth

0-04.

Habitat. — Arctic Ocean, Kamtschatka (Bailey) ; Greenland (Ehrenberg).

1 Artostrobus = Bread-cone ; eZjrof, <rr£<fy3oj.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 186

1482 THE VOYAGE OF H.M.S. CHALLENGER.

2. Artostrobus elegans, Haeckel.

? Eucyrtidium elegans, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,

pL xi. fig. 12.
? Eucyrtidium pauperum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72,

pi. xi. fig. 13.

Shell cylindrical, smooth, with eight to ten internal annular septa. Cephalis subspherical,
with a short, conical horn. Thorax campanulate, with two transverse rows of pores. Abdomen
with six to eight equal joints, each with a single row of pores. (May be described, perhaps, better
as Theoeyrtis elegans. Eucyrtidium pauperum, Ehrenberg, loc. tit., may be a variety of this species.)

Dimensions. — Length of the shell (with nine joints) 01; length of each abdominal joint O'Ol,
breadth O03.

Habitat. — Fossil in Barbados.

Subgenus 2. Artostrobium, Haeckel.

Definition. — All (or the majority) of the joints of the shell with several transverse
rows of pores, in variable number.

3. Artostrobus auritus, Haeckel.

Lithocampe aurita, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 84.
Lithocampe auricula, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 71.
Eucyrtidium auritum, Ehrenberg, 1854, MikrogeoL, Taf. xxii. fig. 25.
Eucyrtidium auritum, Stohr, 1880, Pakeontogr., vol. xxvi. p. 104, Taf. iv. fig. 7.

Shell subcylindrical, with five sharp strictures. All six joints nearly equal in length ; each
with four or five transverse rows of small pores. Cephalis small, flat, hemispherical, with two or
three small, conical, oblique horns. Mouth of the sixth joint a little constricted.

Dimensions. — Length of the shell (with six joints) O12; length of each joint (on an average)
0-02, breadth 0'04 to 0'05.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte, Caltanisetta).

4. Artostrobus biseriatus, n. sp.

Shell cylindrical, smooth, with ten to twelve deep strictures. All joints nearly equal in
size ; each with two transverse rows of small circular pores. Cephalis hemispherical, with a long,
bristle-shaped, curved horn.

Dimensions. — Length of the shell (with twelve joints) 0'24 ; length of each joint 0'02, breadth
0-04.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

REPORT ON THE RADIOLARIA. 1483

5. Artostrobus articulatus, n. sp. (PL 79, fig. 16).

Shell subcylindrical, with elegant longitudinal ribs and five sharp strictures. All six joints
nearly equal in length, each with three or four transverse rows of small circular pores. The
middle joints twice as broad as long. Cephalis hemispherical, with a conical, oblique horn.

Dimensions. — Length of the shell (with six joints) 0'16 ; length of a single joint 0'02 to O03,
breadth O04 to 0'05.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

Genus 646. Lithomitra,1 Butschli/1882, Zeitschr. f. wiss. Zool., p. 529.

Definition. — S tichocorida (vel Stichocyrtida eradiata aperta) with cylindrical
shell, the upper pole of which is rounded, the lower truncate. Cephalis without horn.

The genus Lithomitra differs from the preceding genus Artostrobus in the absence
of a cephalic horn, and therefore bears to it the same relation as Dictyomitra does to
Lithostrobus. In many species the joints are very short, and bear only a single trans-
verse row of pores, and since the constrictions between the joints are often very slight,
Lithomitra becomes very similar to the Dicyrtide Dictyocephalus.

Subgenus 1. Lithomitrella, Haeckel.

Definition. — A single transverse row of small circular pores on each joint. (Some-
times on the uppermost joints two or three rows.)

1. Lithomitra pachyderma, Biitschli.

Lithomitra pachyderma, Biitschli, 1882, Zeitschr. f. wiss. Zool., vol. xxxvi. p. 529.
Eucyrtidium pachyderma, Ehrenberg, 1875, AbhandL d k. Akad. d. Wiss. Berlin, p. 72, Taf.

xi. fig. 21.
Eucyrtidium imbricatum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. xi.

fig. 22.

Shell thick-walled, subcylindrical, with longitudinal ribs, slightly dilated in the middle, with ten
to twelve subequal joints. On the lower edge of each joint a single row of small circular pores.
No external strictures. This and the following species (though separated by Ehrenberg as four
different species) may be united.

Dimensions. — Length of the shell (with ten joints) Oil ; length of each joint O'Ol to 0'012,
breadth 0'04.

Habitat. — Fossil in Barbados.

1 Lithomitra= Stone-cap;

1484 THE VOYAGE OF H.M.S. CHALLENGER.

2. Lithomitra acephala, Biitschli.

Lithomitra acephala, Biitschli, 1882, Zeitschr. f. wi?s. Zool., vol. xxxvi. p, 529.

Eucyrtidium acepfialum, Ehienberg, 1875, AbhandL d. k. Akad. d. Wiss. Berlin, p. 70, Taf.

xi. fig. 5.
Eucyrtidium obstipum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. xi.

fig. 17.

Shell nearly cylindrical, smooth, thick-walled, with twelve to sixteen subequal joints. On each
joint a single row of small circular pores. No external strictures. Scarcely differing from the pre-
ceding species ; the joints are broader and shorter, the cephalis is larger (by union of some joints 1),
and the ribs of the surface less distinct.

Dimensions. — Length of the shell (with .twelve joints) O'l ; length of each joint O'OOG to 0'009,
breadth 0'04.

Habitat. — Fossil in Barbados.

3. Lithomitra lineata, HaeckeL

Lithocampe lineata, Ehrenberg (partim), 1838, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 130; Mikrogeol., 1854, Taf. xxii. fig. 26.
Lithocampe lineata, Haeckel, 1862, Monogr. d. Eadiol., p. 316.
Eucyrtidium lineatum, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 43 ;

Mikrogeol., 1854, Taf. xxxvi. fig. 16; Abhandl. d. k. Akad. d. Wiss. Berlin, 1875, p. 72,

Taf. xi. fig. 9.
Dictyomitra lineata, Stb'hr, 1880, Palaeontogr., vol. xxvi. p. 101, Taf. iii. fig. 22.

Shell subcylindrical, smooth, with longitudinal ribs, and four to eight slight transverse strictures.
Cephalis small, subspherical, with few small pores. Thorax broader, with two or three transverse
rows of pores. Each succeeding (abdominal) joint with a single transverse row of small pores.
Variable and nearly related to the two preceding species (compare my Monograph, loc. cit.~).

Dimensions. — Length of the shell (with six to eight joints) 0'06 to 0'08; length of each joint
(on an average) O'Ol, breadth 0'03.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, in various depths; many
stations ; fossil in Secondary and Tertiary rocks of many places.

4. Lithomitra nodosaria, n. sp. (PL 79, fig. 1).

Shell subcylindrical, with longitudinal ribs, and five to eight transverse strictures, and promi-
nent girdles between them. On each girdle (at the lowermost edge of each joint) a single transverse
row of circular pores. The three or four uppermost joints are united, and represent a conical
cephalis.

Dimensions. — Length of the shell (with six joints) O'l; length of each joint O'Ol to 0'15,
breadth 0'04 to 0'05.

Habitat. — Central Pacific, Station 263 to 274, depth 2350 to 2925 fathoms.

REPORT ON THE RADIOLARIA. 1485

5. Lithomitra eruca, n. sp. (PI. 79, fig. 3).

Shell subcylindrical, diminishing slightly towards both ends, with ten to fifteen slight strictures.
On each joint a single transverse row of circular pores, descending obliquely in the wall. The two
or three first joints form together a roundish cephalis. Usually each joint is three times as broad
as long.

Dimensions. — Length of the shell (with twelve joints) 0'2 ; length of each joint (on an average)
0-016, breadth 0'05.

Habitat. — Central Pacific, Station 265 to 268, depth 2700 to 2900 fathoms; fossil in Barbados.

6. Lithomitra chrysalis, n. sp. (PI. 79, fig. 4).

Shell subcylindrical, diminishing slightly towards both ends, with elegant longitudinal ribs, and
with five to eight slight strictures. Each of the upper joints with two (or sometimes three) trans-
verse rows of small pores ; each of the lower joints with only a single row.

Dimensions. — Length of the shell (with six joints) Oil ; length of each joint O'Ol to 0'015,
breadth 0'04 to 0'05.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Subgenus 2. Lithomitrissa, Haeckel.

Definition. — All (or the majority) of the joints of the shell with several trauverse
rows of pores, in variable number.

7. Lithomitra cylindrica, n. sp.

Shell cylindrical, smooth, with twelve to sixteen internal septal rings (without external stric-
tures). On each joint two transverse rows of small, regular, circular pores. The hemispherical
cephalis also has two rows of pores. Each joint is twice as broad as long.

Dimensions. — Length of the shell (with sixteen joints) 0'3; length of each joint 0-02, breadth
0-04.

Habitat. — South Pacific, Station 297, depth 1775 fathoms.

8. Lithomitra costata, Haeckel.

Dictijomitra costata, Stohr, 1880, Palaeontogr., vol. xxvi. p. 101, Taf. iii. fig. 23.

Shell with longitudinal ribs, in the upper half conical, in the lower half cylindrical, with six to
eight slight strictures. Small, circular pores in regular transverse rows ; three rows in each upper
joint, two rows in each lower joint (the last joints sometimes confluent).

1486 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Length of the shell (with eight joints) 015 ; length of each joint 0'017 to 0-023,
breadth 0'04 to 0'05.

Habitat. — Fossil in Tertiary rocks of Sicily ; Grotte (Stohr), Caltanisetta (Haeckel).

9. Lithomitra punctata, Haeckel.

Lithocampe punctata, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 84.

Eucyrtidium punctatum, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 24.
Dictyomitra punctata, Stohr, 1880, Palseontogr., vol. xxvi. p. 101, Taf. iii. fig. 24.

Shell subcylindrical, smooth, with four to six distinct strictures. Cephalis small, subspherical.
Thorax campanulate-conical. Abdomen cylindrical, with three to four equal joints. In each joint
five to six transverse rows of small, circular pores, quincuncially disposed.

Dimensions. — Length of the shell (with five joints) O'l ; length of each joint (except the first)
0-02, breadth 0'05.

Habitat. — Fossil in Tertiary rocks of Sicily ; Caltanisetta (Ehrenberg), Grotte (Stohr).

10. Lithomitra seriolata, Haeckel.

Eucyrtidium seriolatum, Ehrenberg, 1858, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 33.
Lithocampe seriolata, Haeckel, Monogr. d. RadioL, p. 316.

Shell subcylindrical, smooth, with four to six sharp strictures. Cephalis small, hemispherical.
Thorax conical. Abdomen cylindrical, with three to five different joints of alternate sizes. Small
circular pores in transverse rows ; three or four rows in the third and fifth joints, seven or eight
rows in the second, fourth, and sixth joints.

Dimensions. — Length of the shell (with six joints) O'l ; length of the second and fourth joints
0-03, of the third and fifth joints 0'015.

Habitat. — Mediterranean, Crete (Ehrenberg), Corfu (Haeckel).

11. Lithomitra hyperborea, Haeckel.

Eucyrtidium hyperboreum, Bailey, 1856, Amer. Journ. Sci. and Arts, vol. xxii., pi. i. fig. 10.
Lithocampe hyperborea, Haeckel, 1862, Monogr. d. Radiol., p. 315.

Shell cylindrical, with prominent longitudinal ribs and six deep strictures. Cephalis hemi-
spherical. On each joint three to four transverse rows of small, obsolete pores. Each joint is
about twice as broad as long.

Dimensions. — Length of the shell (with six joints) 0'12 ; length of each joint 0'02, breadth 0'04.

Habitat. — Arctic and Northern Pacific, Karntschatka (Bailey).

REPORT ON THE RADIOLARIA. 1487

12. Lithomitra australis, Haeckel.

Lithocampe australis, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 187.
Lithocampe australis, Haeckel, 1862, Monogr. d. RadioL, p. 315.

Eucyrtidium australe, Elirenberg, ] 847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 43 ;
Mikrogeol., 1854, Taf. xxxv., A 21, fig. 18.

Shell subcylindrical, smooth, with five deep strictures. The two middle joints somewhat
larger than the two proximal and the two distal joints. Pores small, circular, in regular, transverse
rows ; two rows in the first and the sixth joints, five rows in the second and the fifth, seven or
eight rows in the third and fourth joints. The two latter are twice as broad as long.

Dimensions. — Length of the shell (with six joints) 014 ; length of the four smaller joints
0-017, of the two larger joints 0'035 ; breadth 0'06.

Habitat. — Antarctic Sea (lat. 78° 10' S., long. 162° W.) Eoss.

13. Lithomitra eminens, Haeckel.

Lithocampe &>ninetis, Stohr, 1880, Palseontogr., vol. xxvi. p. 102, Taf. iv. fig. 2.

Shell subcylindrical, rough, with seven slight strictures. The two or three middle joints half
as long as the two preceding and the two following joints. Cephalis small, subspherical. Pores
small, in subregular, transverse rows, on the fifth and sixth joints only two rows, on the second,
third, seventh, and eighth joints four to five rows.

Dimensions. — Length of the shell (with eight joints) 0'27 ; length of the fifth and sixth joints
017, of the others 0'03 to 0'04 ; breadth 0'08.

Habitat. — Fossil in Tertiary rocks of Sicily, Grotte (Stohr).

14. Lithomitra infundibulum, n. sp. (PL 79, fig. 5).

Shell in the upper half subconical, in the lower half subcylindrical, rough, with four slight
strictures. Cephalis hemispherical. Thorax conical. Abdomen subcylindrical, three-jointed.
Pores of the second, third, and fourth joints funnel-shaped, with very small inner, and larger
double-contoured outer aperture ; on the thorax twelve transverse rows, on the third and fourth
joints five rows. Fifth joint with irregular, polygonal pores.

Dimensions. — Length of the shell (with five joints) 0'2 ; length of the thorax 0'06, breadth
0'08 ; length of each abdominal joint 0'04, breadth 0'08.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 647. Eucyrtidium,1 Ehrenberg, 1847, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 54.

Definition. — S ticliocorida (vel Stichocyrtida eradiata aperta) with ovate or
spindle-shaped shell, the mouth of which is constricted, but not prolonged into a tube.
Gephalis with a solid horn.

1 Eucyrtidium=rNice small basket; tv, xt/£n'S<o».

1488 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Eucyrtidium (as here stated in the definition) and the three following
nearly allied genera differ from the preceding Stichocorida in the more or less con-
stricted mouth, and the consequent ovate or spindle-form of the multiarticulate shell.
The middle joints of the latter are broader than the upper and the lower joints. In
the earlier definition given in my Monograph (1862, pp. 312 to 320), the genus had a
much wider sense ; but the very large number of species since detected requires a more
strict definition. Ehrenberg confounded in his genus Eucyrtidium a large number of very
different Cyrtoidea. In his last works (1872, 1875) he described not less than one
hundred and eleven species, fifty-five fossil and fifty-six living (eight fossil species
being yet living). But, in reality, these one hundred and three species belong to
twenty or twenty -two very different genera of C y r t o i d e a.

Subgenus 1. Eucyrtis, Haeckel, 1881, Prodromus, p. 438.

Definition. — All joints of the shell nearly of the same length (excepting often the
first). Surface smooth or rough, without spines.

1. Eucyrtidium acuminatum, Ehrenberg.

Eucyrtidium acuminatum, Ehrenberg, 1847, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,

p. 43 ; Mikrogeol, 1854, Taf. xxii. fig. 27.

Eucyrtidium acuminatum, Stohr, 1880, Palseontogr., vol. xxvi. p. 104, Taf. iv. fig. 6.
Eucyrtidium acuminatum, Haeckel, 1862, Monogr. d. Eadiol., p. 326.
Lithocampe actiminata, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 84.

Shell smooth, slender, nearly spindle-shaped, without external strictures, but with eight to nine
internal septal rings. All joints (except the first) nearly of the same length (or the upper some-
what longer). The fifth joint is the broadest. Cephalis small, subspherical, with a short, conical
horn. Pores very small and numerous, regular, hexagonal, four to six on the length of each joint.

Dimensions. — Length of the shell (with eight joints) 0'14 ; length of each joint about 0'02 ;
greatest breadth, in the fifth joint, 0'07.

Habitat. — Fossil in Tertiary rocks of Sicily (Caltanisetta, Grotte, &c.).

2. Eucyrtidium tropezianum, Haeckel.

Lithocampe tropeziana, J. Miiller, 1858, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 42, Taf. vii.

figs. 4, 5, 6.
Lithocampe tropeziana, Haeckel, 1862, Monogr. d. Radiol., p. 326.

Shell smooth, slender, nearly spindle-shaped, without external strictures, but with seven or eight
internal septal rings. All joints of the same length. The fifth and sixth joints are the broadest.
Cephalis hemispherical, with a pyramidal horn of the same length. Pores very small and
numerous, regular, circular, hexagonally framed, five to six in the length of each joint. (Very near
to the preceding species, but more regular, and with different pores.)

REPORT ON THE RADIOLARIA. 1489

Dimensions. — Length of the shell (with eight joints) 016, length of each joint 0'02 ; greatest
breadth (in the fifth joint) O'OT.

Habitat. — Mediterranean, French shore, St. Tropez (J. Miiller), surface.

3. Eucyrtidium hexagonatum, n. sp. (PI. 80, fig. 11).

Shell smooth, ovate, with six to seven internal septal rings. All joints (except the first) nearly
of the same length ; the sixth joint is the broadest. The seventh and eighth joints (broken off in
the specimen figured) gradually decrease toward the constricted mouth, which is as broad as the
septum between the third and fourth joints. Cephalis and thorax together pear-shaped, with circular
pores, sharp lumbar stricture, and a stout, pyramidal horn of the same length. The five or six
abdominal joints with regular, hexagonal pores, six or seven in course of the length of each joint.

Dimensions. — Length of the shell (with eight joints) 0'2, length of each joint 0'025 to 0'03 ;
greatest breadth (in the sixth joint)*01.

Habitat. — Central Pacific, Stations 266 to 272, depth 2425 to 2925 fathoms.

4. Eucyrtidium fusiforme, n. sp.

Shell smooth, slender, spindle-shaped, without external strictures, but with ten to twelve
internal septal rings. All joints of the same length ; the sixth joint is the broadest. Cephalis
conical, with a pyramidal horn of the same length. Pores regular, circular, four or five in course
of the length of each joint. (Differs from all other species of the genus in the regular, slender,
spindle form ; the constricted mouth of the last joint is half as broad as the sixth joint.)

Dimensions. — Length of the shell (with twelve joints) 0-24, length of each joint 0-02 ; greatest
breadth (on the sixth joint) 0-06, of the mouth O03.

Habitat. — Indian Ocean, Maldive Islands (Haeckel, 1882), surface.

5. Eucyrtidium doliolum, n. sp.

Shell smooth, barrel-shaped, or nearly spindle-shaped, with eight or nine distinct strictures. All
joints (except the first) of the same length ; the fourth joint is the broadest. Cephalis small, sub-
spherical, with two short, divergent, conical horns. Pores regular, circular, hexagonally framed,
three to four in course of the length of each joint.

Dimensions. — Length of the shell (with ten joints) 0'2, length of each joint 0'022 ; greatest
breadth (in the fourth joint) 0'08.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Subgenus 2. Stichocyrtis, Haeckel, 1881, Prodromus, p. 438.

Definition. — All joints of the shell nearly of the same length (excepting often the
first). Surface spiny.

(ZOOL. CHALL. EXP.— PAKT XL. — 1886.) Rr 187

1490 THE VOYAGE OF H.M.S. CHALLENGER.

6. Eucyrtidium spinosum, n. sp.

Shell spiny, slender, ovate, without external strictures, but with seven or eight internal septal
rings. Conical spines of different lengths are scattered over the whole surface. All joints have
nearly the same length ; the sixth is the broadest. Cephalis conical, with one large and two or
three smaller conical horns. Mouth constricted, half as broad as the shell. Pores irregular,
roundish, double-edged, three to four on the length of each joint.

Dimensions. — Length of the shell (with eight joints) 016, length of each joint 0'02; greatest
breadth (on the sixth joint) 0'06.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

7. Eucyrtidium chrysalidium, n. sp.

Shell spiny, spindle-shaped, with four to five slight strictures, above each stricture a circle or
girdle of conical spines (as in the similar Cyrtophormis cingulata, PL 78, fig. 18). All joints (except
the first) have the same length. Cephalis subspherical, with a bunch of divergent spines. Mouth
constricted, only one-third as broad as the third joint, which is the broadest. Pores subregular,
circular, four to five on the length of each joint.

Dimensions. — Length of the shell (with six joints) 018, length of each joint 0'032; greatest
breadth 0-08.

Habitat. — South Pacific, Station 302, depth 1450 fathoms.

Subgenus 3. Artocyrtis, Haeckel.

Definition. — Joints of the shell of very different lengths. Surface smooth or rough,
without spines.

8. Eucyrtidium profundissimum, Ehrenberg.

Eucyrtidium profundissimum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293,
Taf. vii. fig. 12.

Shell smooth, campanulate, ovate, with three internal septal rings. Four joints of different
lengths. Cephalis subspherical, with a small bristle-shaped horn. Thorax campanulate, nearly twice
as long as each of the two following joints, which are nearly equal in breadth. Terminal mouth
wide open, little constricted. Pores very small and numerous, regular, hexagonal.

Dimensions. — Length of the shell (with four joints) 012 ; length of the thorax 0'05, breadth
0-07.

Habitat — Pacific ; many Stations (Stations 206, 225, 253, 265, &c.), in depths between 2000
and 4000 fathoms.

REPORT ON THE RADIOLARIA. 1491

9. Eucyrtidium anthophorum, Haeckel.

Thyrsocyrtis anthophora, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 84, Taf. xii.
fig. 9.

Shell smooth, slender, ovate, with three slight strictures. Four joints of different lengths.
Cephalis subspherical, with a stout, club-shaped, spinulate or branched horn of the same length.
Second campanulate and third subcylindrical joint about equal in size. Fourth joint only half as
long, with slightly constricted mouth (broken off in Ehrenberg's figure). Pores small and
numerous, regular, circular, quincuncial.

Dimensions. — Length of the shell (with four joints) 012 ; length of the second and of the
third joints 0'04, breadth 0'05 to 0'06.

Habitat. — Fossil in Barbados.

10. Eucyrtidium hertwigii, n. sp. (PI. 80, fig. 12).

Shell smooth, ovate, truncate, with three distinct strictures. Four joints of different lengths.
Cephalis campanulate, with an internal rod-cross, and a stout pyramidal horn of the same length.
Second joint campanulate. Third joint larger, subcylindrical, with a variable number of irregular,
longitudinal ribs, some of which are prolonged into the second and fourth joints. The latter is
only half as long, and slightly constricted towards the mouth. Pores small and numerous,
subregular, circular.

Dimensions. — Length of the shell (with four joints) 0'22. Length of the single joints, a 0'03,
b 0-06, c 0-08, d 0'05 ; breadth, a 0'03, b 01, c 012, d Oil.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

11. Eucyrtidium lagena, Haeckel.

Eucyrtidium lagena, Haeckel, 1862, Monogr. d. Radiol., p. 325, Taf. iv. fig. 11.
Liihocampe lagena, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 839.

Shell smooth, bottle-shaped, with three distinct strictures. Four joints of different sizes.
Cephalis small, spherical, with a bristle-shaped horn of the same length. Second joint conical,
third subcylindrical, fourth inflated, with slightly constricted mouth ; their lengths about equal.
Pores subregular, hexagonal, large, with thin bars.

Dimensions. — Length of the shell (with four joints) 016 ; length of each of the three lower
joints about 0'05, breadth 0'05 to 0'064.

Habitat. — Mediterranean (Messina).

12. Eucyrtidium teuscheri, n. sp. (PI. 77, fig. 5).

Shell smooth, bottle-shaped, with three distinct strictures. Four joints of different lengths.
The third joint four times as long as each of the two first joints, and longer than the fourth, which

1492 THE VOYAGE OF H.M.S. CHALLENGER.

is little constricted towards the mouth. The greatest breadth is in the middle of the shell.
Cephalis hemispherical, with a small, conical horn of the same length. Pores large, circular, of
variable sizes. Dedicated to Dr. Eeinhold Teuscher.

Dimensions. — Length of the shell (with four joints) 016. Length of the single joints, a G'015,
b 0-02, c 0-07, d 0-055 ; breadth, a 0'03, I 0-05, c 0'08, d 0-06.

Habitat. — Central Pacific, Stations 266 to 274, depth 2350 to 2925 fathoms.

13. Eucyrtidium biitschlii, n. sp. (PI. 77, fig. 7).

Shell rough, slender, ovate, truncate, with three distinct strictures. Four joints of different
lengths ; the third is the largest, inflated, subspherical. Fourth joint subcylindrical, little constricted
towards the truncate mouth. Cephalis hemispherical, with a small, conical horn. Pores circular,
much larger in the third joint than in the three others.

Dimensions. — Length of the shell (with four joints) 016. Length of the single joints, a 0'02,
b 0-03, c 0-06, d 0'05 ; breadth, a 0'03, b 0'07, c 0'09, d 0'07.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

14. Eucyrtidium galathea, Ehrenberg.

Eiicyrtidium galathece, Ehrenberg, 1854, Monatsber. d. k. preuss. Akacl. d. Wiss. Berlin, p. 242.

Shell smooth, campanulate, with three deep strictures. Four joints of different lengths ; the
fourth joint is the broadest, twice as long as the third and the second, three times as long as the
hemispherical cephalis, which bears a stout, pyramidal, oblique horn of twice the length. Mouth
little constricted. Pores regular, circular, in transverse rows, three rows in each of the three first
joints, five or six rows in the last joint.

Dimensions. — Length of the shell (with four joints) 012 ; length of the fourth joint 0'05,
breadth 0'07.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

15. Eucyrtidium galea, Haeckel.

Eucyrtidium galea, Haeckel, 1862, Monogr. d. Eadiol., p. 324, Taf. vii. figs. 8-10.
Litliocampe galea, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 838.

Shell smooth, helmet-shaped, with four sharp strictures. Five joints of different lengths.
Cephalis small, spherical, with a thin pyramidal horn of the same length. Second joint conical,
about as long as the third, longer than the fourth and the fifth joints. The third joint is the
broadest. Pores regular, circular, small and numerous.

Dimensions. — Length of the shell (with five joints) 018 ; length of the second and the third
joints 0-05, of the fourth 0'03 ; breadth 0'08 to 01.

Habitat. — Mediterranean (Messina), surface.

REPORT ON THE RADIOLARIA. 1493

16. Eucyrtidium eruca, Ehrenberg.

Eucyrtidium eruca, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70, Taf. x. fig. 13.

Shell smooth, slender, ovate, or nearly spindle-shaped, with four sharp strictures. Five joints
of different lengths, the third and fourth nearly equal, twice as long as the fifth, one and a half times
as long as the second ; the fourth joint is the broadest. Mouth little constricted. Cephalis sub-
spherical, with a small, conical horn. Pores small and numerous, subregular, circular.

Dimensions. — Length of the shell (with five joints) 012 to 014 ; length of the third and the
fourth joints, 0'03 to 0'04, breadth 0'04 to 0'05.

Habitat. — Cosmopolitan ; Atlantic, Pacific, in different depths ; also fossil in Barbados and
Sicily.

17. Eucyrtidium montiparum, Ehrenberg.

Eucyrtidium montiparum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72,
Taf. ix. fig. 11.

Shell rough, nearly spindle-shaped, with five deep strictures. Six joints of different lengths,
the third and fourth nearly equal, longer than the fifth and the sixth joints ; the fourth joint is
the broadest. Mouth slightly constricted. Cephalis very small, hemispherical, hyaline, with a
short, conical horn. Pores subregular, circular, twice as broad as in the similar smaller preceding
species.

Dimensions. — Length of the shell (with six joints) 0'2 ; length of the third and the fourth joints
0-05, breadth 0'07 to 0'08.

Habitat. — Fossil in Barbados.

18. Eucyrtidium cienkowskii, n. sp. (PI. 80, fig. 9).

Shell smooth, subconical, with five distinct strictures. Six joints of different lengths ; the third
joint conical, one and a half to two times as long as each of the other joints ; the fifth joint is the
broadest. Mouth wide, very slightly constricted. Cephalis hemispherical, with an oblique pyra-
midal horn of the same length. Pores regular, circular, in dense transverse rows ; five to six rows
in each of the three last joints, eight to nine rows in the third joint.

Dimensions. — Length of the shell (with six joints) 016, length of the third joint 0'04, of each
following joint 0'02 ; greatest breadth (in the fifth joint) 0'08.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

19. Eucyrtidium elongatum, Stohr.

Eucyrtidium elongatum, Stohr, 1880, Palseontogr., vol. xxvi. p. 105, Taf. iv. fig. 10.

Shell rough, slender, nearly spindle-shaped, variable in size and form, with six to seven distinct
strictures. Seven to eight joints of different lengths, often alternately longer and shorter. The second

1494 THE VOYAGE OF H.M.S. CHALLENGER.

and the last joints are the longest, the third is the broadest. Mouth slightly constricted (broken
off in Stb'hr's figure). Cephalis small, subspherical, with a small, oblique, curved horn. Pores
irregular.

Dimensions. — Length of the shell (with seven joints) 0'2 ; length of the single joints, between
0-02 and 0'04, breadth 0'06 to 0'08.

Habitat. — Fossil in Sicily (Grotte, Caltanisetta).

20. Eucyrtidium stohrii, n. sp.

Shell smooth, spindle-shaped, gradually diminishing towards both ends, with eight to ten distinct
strictures. Nine to eleven joints of different lengths ; the two or three middle joints — fifth, sixth,
and seventh — longer and broader than the other joints ; the broadest is the fifth joint, which is twice
to three times as long as the first and last joints. Cephalis subspherical, with a conical horn of
the same length. Terminal mouth strongly constricted, one-half or one-third as broad as the fifth
joint. Pores small, regular, circular.

Dimensions. — Length of the shell (with ten joints) 0'22 ; length of the largest (fifth joint) 0'03,
breadth 0'09.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

21. Eucyrtidium scalarium, n. sp.

Shell smooth, slender, ovate, with nine to ten deep strictures, and ten to eleven separate
step-like joints of different lengths. The sixth joint is the longest, twice as long as the fourth, and
three times as long as the third and the last joint ; the seventh and eighth joints are the broadest,
one and a half times as broad as the wide mouth. Cephalis hemispherical, with a short pyramidal
horn of the same length. Pores small and numerous, subregular, square, in regular transverse rows ;
six rows in the sixth joint, three rows in the last joint. (Somewhat similar to Spirocyrtis scalaris,
PI. 76, fig. 14, but ovate, not conical and not spiral.)

Dimensions. — Length of the shell (with eleven joints) 0'22, breadth Oil ; length of the last
joint O'Ol, of the sixth 0'03.

Habitat. — North Atlantic, Station 64, surface.

Subgenus 4. Acanthocyrtis, Haeckel, 1881, Prodromus, p. 437.
Definition. — Joints of the shell of very different lengths. Surface spiny.

22. Eucyrtidium tricinctum, n. sp. (PL 78, fig. 13).

Shell spiny, spindle-shaped, with three distinct strictures. Four joints of different lengths, the
first and third half as long as the second and fourth ; the third joint is the broadest, four times as

REPORT ON THE RADIOLARIA. 1495

broad as the strongly constricted mouth. Spines irregularly scattered over the lower half of the
shell, increasing in size towards the mouth. Pores subregular, circular.

Dimensions. — Length of the shell (with four joints) 0'25. Length of the single joints, a, 0'03
b 0-08, c 0-04, d D'09 ; breadth (of the third joint) 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

23. Eucyrtidium armatum, n. sp. (PI. 78, fig. 14).

Shell spiny, spindle-shaped, with three distinct strictures. Four joints of different lengths, the
second and third joints of the same length, shorter than the fourth joint ; the third joint is the
broadest, four times as broad as the strongly constricted mouth. The latter, as well as the conical
cephalis, is armed with an irregular bunch of strong conical spines, while numerous smaller spines
are scattered over the whole surface. Pores irregular, roundish, double-contoured.

Dimensions. — Length of the shell (with four joints) 0'2. Length of the single joints, a 0'02, b 0'05,
e 0'05, d 0-08 ; breadth (of the third joint) 01.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

24. Eucyrtidium conostoma, n. sp. (PI. 78, fig. 16).

Shell spiny, spindle-shaped, with four distinct strictures. Five joints of different lengths, having
the proportion = 1 : 2 : 3 : 6 : 10. The fourth joint is the broadest, inflated, twice as broad as long.
Cephalis small, with a conical horn of the same length. Fifth joint inversely conical, with a narrow
mouth, broader than the cephalis. Short conical spines are scattered over the whole surface. Pores
subregular, circular.

Dimensions. — Length of the shell (with five joints) 0'22. Length of the single joints, a O'Ol,
b 0-02, c 0-03, d 0'06, e 01 ; breadth (of the fourth joint) 0'09.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

25. Eucyrtidium ehrenbergii, n. sp. (PI. 78, fig. 15).

Shell spiny, spindle-shaped, with four distinct strictures (the first and the fourth are by a mis-
take not distinctly figured). Five joints of different lengths, having the proportion = 2:3:4:2:5.
The third joint is the broadest, twice as broad as long, and twice as broad as the constricted
mouth. Whole surface covered with strong spines. Pores irregular, roundish.

Dimensions. — Length of the shell (with five joints) 016. Length of the single joints, a 0'02,
b 0-03, c 0-04, d 0'02, e 0'05 ; breadth (in the third joint) 0'08.

Habitat. — Western Tropical Pacific, Station 220, depth 1100 fathoms.

26. Eucyrtidium ovatum, n. sp.

Shell spiny, inversely ovate, with five sharp strictures. Six joints of different lengths, having the
proportion = 1:3:2:1:1:3. The third joint is the broadest, three times as broad as the con-

1496 THE VOYAGE OF H.M.S. CHALLENGER.

stricted mouth. Cephalis with a stout pyramidal horn of the same length. Whole surface spiny.
Pores irregular, roundish.

Dimensions. — Length of the shell (with six joints) 0'22. Length of the single joints, a 0'02,
I 0-06, c 0-04, d 0-02, e 0'02,/0'06 ; breadth (in the third joint) Oil.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

Genus 648. Eusyringium,1 Haeckel, 1881, Prodromus, p. 437.

Definition. — S tichocorida (vel Stichocyrtida eradiata aperta) with ovate or
spindle-shaped shell, the mouth of which is constricted, and prolonged into a terminal
cylindrical tube. Cephalis with a solid horn.

The genus Eusyringium differs from the preceding closely allied genus Eucyrtidium
in the peculiar formation of the last shell-joint, representing a narrow, cylindrical,
fenestrated tube. It exhibits, therefore, to the latter the same relation as
Theosyringium bears to Theocorys.

Subgenus 1. Eusyringartus, Haeckel.

Definition. — Shell with three strictures and four joints ; the third joint is the
largest, inflated, and much broader than the three others.

1. Eusyringium conosiphon, n. sp. (PI. 78, fig. 10).

Shell with four joints, very thick-walled, rough. Cephalis hemispherical, with a very stout,
smooth, three-sided pyramidal horn of the same length and breadth. Thorax hemispherical.
Third joint subspherical, three times as long, and twice as broad as the thorax, and of the same
length as the slender, inversely conical fourth joint. Pores in the three first joints subregular,
circular, in the fourth joint irregular.

Dimensions. — Length of the shell (with four joints) 0'25. Length of the single joint a 0'02,
I 0-03, c 01, d 01; breadth 012.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Eusyringium pachy siphon, n. sp. (PI. 78, fig. 11).

Shell with four joints, very thick-walled, rough. Cephalis conical, with a thick, dimpled,
conical horn of the same length. Thorax hemispherical. Third joint inflated, subspherical, and
fourth joint slender, inversely conical, as in the similar preceding species. Differs from the latter

1 Eusyringium = Nice small tube ; if, o

REPORT ON THE RADIOLARIA. 1497

mainly in the form of the cephalic horn, and the cylindrical tube of the last joint. Pores sub-
regular, circular.

Dimensions. — Length of the shell (with four joints) 0'3. Length of the single joints, a 0'03,
b 0-03, c 012, d 012 ; breadth 015.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Eusyringium macrosiphon, n. sp. (PL 78, fig. 12).

Shell with four joints, thick- walled, rough. Cephalis subspherical, with a large, dimpled, conical
horn of twice the length. The three following joints nearly of the same shape as in the two
similar preceding species. It differs from these in the smaller size, the larger cephalic horn, and
the longer tube of the fourth joint, which is twice as long as the subspherical third joint (in the
figure the lower half is broken off). Pores subregular, circular.

Dimensions. — Length of the shell (with four joints) 0'3. Length of the single joints, a 0'03,
b 0-03, c 0-08, d 016 ; breadth 0'09.

tf.— Central Pacific, Station 266, depth 2750 fathoms.

4. Eusyringium leptosiphon, n. sp.

Shell with four joints, thin-walled, smooth. Cephalis subspherical, with a large, dimpled, slender,
conical horn of three times the length. Thorax hemispherical. Third joint ovate, four times as
long as the thorax, and of the same length as the thin, cylindrical tube of the fourth joint. Differs
from the three preceding species in the more slender form and the thinness of the tube. Pores
irregular, roundish.

Dimensions. — Length of the shell (with four joints) 0-33. Length of the single joints, a 0'02,
b 0-03, c 013, dO-15; breadth 01.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

5. Eusyringium sipho, Haeckel.

Eucyrtidium sipho, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 72, Taf. ix. fig. 2.

Shell with four joints, thick-walled, smooth. Cephalis subspherical, hyaline, without pores,
with a thick, conical horn of twice the length. Thorax hemispherical. Third joint ovate, four
times as long as the thorax, and of the same length as the thin, cylindrical fourth joint. Pores
subregular, circular, in the fourth joint twice as broad as in the third, and three times as broad as
in the second joint.

Dimensions. — Length of the shell (with four joints) 0'22. Length of the single joints, a 0'02,
b 0-02, c 0-09, d 0'09 ; breadth 0'08.

Habitat. — Fossil in Barbados.

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 188

1498 THE VOYAGE OF H.M.S. CHALLENGER.

6. Eusyringium fistuligerum, Haeckel.

Eucyrtidium fistuligerum, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 70,
Taf. ix. fig. 3.

Shell with four joints, thin-walled, smooth. Cephalis subspherical, with numerous very small pores,
and a stout, pyramidal horn of the same length. Thorax hemispherical. Third joint subspherical,
four times as long as the thorax, and of the same length as the slender, inversely conical or cylindrical,
fourth joint. Pores irregular, roundish or circular, in the fourth joint twice as broad as in the two
preceding joints.

Dimensions. — Length of the shell (with four joints) 0'2. Length of the single joints, a O02,
I 0-02, c 0-08, d 0-08 ; breadth 0'09.

Habitat. — Fossil in Barbados.

Subgenus 2. Eusyringoma, Haeckel.

Definition. — Shell with four or more strictures, and five or more joints ; the last joint
is strongly constricted, and forms a narrow cylindrical tube.

7. Eusyringium lagenoides, Haeckel.

Eucyrtidium lagenoides, Stohr, 1880, Palseontogr., vol. xxvi. p. 104, Taf. iv. fig. 8.

Shell with five joints, and four sharp strictures, nearly spindle-shaped. The third joint is twice
as long as the second and the fourth. Cephalis small, cap-shaped, with a thin conical horu of the
same length. The fifth joint is in Stohr's figure broken off, but well conserved in a specimen from
Caltanisetta, and represents a slender cylindrical tube, with few pores, half as long as the shell.
Pores small, subregular, circular, quincuncial.

Dimensions — Length of the shell (with five joints) 0'24, breadth 0'08 ; length of the third
joint 0-06, of the second and the fourth 0'03, of the fifth 01 ; breadth of the basal tube 0'027.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte, Caltauisetta).

8. Eusyringium rhaphanus, Haeckel.

Eucyrtidium rhaphanus, Stohr, 1880, Palaeontogr., vol. xxvi. p. 106, Taf. iv. fig. 12.

Shell with six or seven joints of very different lengths, in the upper half campanulate, in the
lower cylindrical. The second and the two last joints are the longest. Cephalis small, subspherical,
with a short conical horn. The last joint is a narrow cylindrical tube of variable length, scarcely one-
fourth as broad as the preceding joints. Pores in the upper joints regular, circulai, in the lower
irregular, roundish.

Dimensions. — Length of the shell (with seven joints) 0'2, breadth 01; length of the second and
last joints 0'03 to 0'04 ; breadth of the basal tube 0-025.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte).

REPORT ON THE RADIOLABIA. 1499

9. Eusyringium siphonostoma, n. sp. (PI. 80, fig. 14).

Shell with eight joints, in the upper half slender, conical, in the lower half cylindrical. The
single joints are separated by seven internal annular septa. The third and the seventh joints are
the largest, twice as long as the three intercalated joints. Cephalis small, cap-shaped, with a
conical horn of twice the length. The last joint (broken off in the specimen figured) is a narrow
cylindrical tube, one-third as long and one-third as broad as the shell. Pores regular, circular, quin-
cunciaL

Dimensions. — Length of the shell (with eight joints) 0'24, breadth 0'08 ; length of the single
joints 0-02 to 0'04 ; breadth of the basal tube 0'03.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

10. Eusyringium cannostoma, n. sp. (PI. 80, fig. 13).

Shell with nine or ten joints, slender ovate. The single joints are separated by eight or nine
internal annular septa. The third joint is the longest, about twice or three times as long as each
following joint. Cephalis hemispherical, with a curved, conical horn of the same length. The last
joint is a narrow, cylindrical tube, about as long as the third joint, but only one-fourth as broad.
Pores small, regular, circular, quincuncially disposed, and hexagonally framed.

Dimensions. — Length of the shell (with ten joints) 0'22, breadth 0'08 ; length of the third joint
0-04, of the other joints O'Ol to 0'02, of the basal tube 0'04 ; breadth of the latter 0'02.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 649. Siphocampe,1 Haeckel, 1881, Prodromus, p. 438.

Definition. — S tichocorida (vel Stichocyrtida eradiata aperta) with ovate or
spindle-shaped shell, the mouth of which is constricted, but not prolonged into a tube.
Cephalis with an oblique, open, apical tube.

The genus Siphocampe differs from the closely allied genera Lithocampe and
Eucyrtidium in a very remarkable character, viz., the development of a hollow
cylindrical tube on the cephalis. This probably serves for the emission of a bunch of
pseudopodia. It has the same position and the same oblique direction on the cephalis
as the solid apical horn of Eucyrtidium

Subgenus 1. Siphocampula, Haeckel.
Definition. — All joints of the shell (excepting the first) are nearly equal in length.

1 Siphocampe— Caterpillar with a tube; atQuy, xdft.^»i.

1500 THE VOYAGE OF H.M.S. CHALLENGER.

1. Siphocampe tubulosa, n. sp. (PI. 79, fig. 13).

Shell slender, nearly spindle-shaped, with eight deep transverse strictures, and elegant
longitudinal ribs. Nine joints slightly different in length and shape. Cephalis flat, cap-shaped,
with three or four transverse rows of small pores, and a cylindrical, oblique tubule of twice the
length. Each successive joint with a single transverse row of regular, circular pores at its lower
edge, separated by divergent, longitudinal ribs. Last joint shorter, with a hyaline annular
peristome of the same length. Mouth half as broad as the middle part of the shell.

Dimensions. — Length of the shell (with nine joints) 0'24 ; length of each joint (on an
average) 0'02 to 0'03 ; breadth 0'08.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Siphocampe annulosa, n. sp. (PI. 79, fig. 10).

Shell slender, subcylindrical, with nine slight transverse strictures, and interrupted longitudinal
ribs. Ten joints nearly equal in length and shape, excepting the two first, which together form a
hemispherical cephalothorax, with six to eight transverse rows of pores. Tubule of the cephalis
short and wide, truncate, conical. Each of the eight abdominal joints with a single transverse
row of small pores. Mouth constricted, without tubulose peristome, half as broad as the shell.

Dimensions. — Length of the shell (with ten joints) 018 ; length of each joint (on an average)
0-02, breadth 0-07.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

3. Siphocampe caminosa, n. sp. (PI. 79, fig. 12).

Shell slender, subcylindrical, with six deep tranverse strictures. Seven joints nearly equal in
length and breadth. Cephalis hemispherical, with an oblique, cylindrical tubule of twice the length
(in the figure the greater part is broken away). Small circular pores in transverse rows and in
variable number ; usually three rows in the first and the last joint, five rows in the fourth joint, four
rows in each of the other joints. Mouth constricted, with a short tubulose peristome, only one-
third as broad as the shell.

Dimensions. — Length of the shell (with seven joints) 0'18 ; length of each joint (on an
average) 0'025, breadth 0'055.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Siphocampe erucosa, n. sp. (PI. 79, fig. 11).

Shell slender, nearly spindle-shaped, with five slight transverse strictures. Six joints nearly
equal in length. The two first joints are united, and form together a hemispherical cephalothorax,
with a short, oblique, cylindrical tubule. Pores regular, circular, double-contoured, in regular,
transverse rows ; two rows in the first and the last joints, four rows in each of the four middle
joints. Mouth constricted, without peristome, only one-third as broad as the shell.

REPORT ON THE RADIOLARIA. 1501

Dimensions. — Length of the shell (with six joints) 014 ; length of each joint (on an average)
0-02, breadth 0'07.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

Subgenus 2. Siphocampium, Haeckel, 1881, Prodromus, p. 437.
Definition. — The joints of the shell are very different in length.

5. Siphocampe quadrantalis, n. sp.

Shell nearly spindle-shaped, with three deep strictures. Four joints of very different lengths.
Cephalis subspherical, with an oblique cylindrical tubule of twice the length, and with few small
pores. Thorax ovate, half as long as the shell, with twelve transverse rows of small pores.
Abdomen with two short joints, each of which has two transverse rows of pores. Mouth con-
stricted, one-third as broad as the thorax.

Dimensions. — Length of the shell (with four joints) 018 ; length of the thorax 01, breadth
0-08.

Habitat. — Western Tropical Pacific ; North Coast of New Guinea, Station 220, depth 1100
fathoms.

6. Siphocampe spiralis, n. sp. (PI. 79, fig. 14).

Shell nearly spindle-shaped, with eight slight strictures. Nine joints of very different lengths.
Cephalis subspherical, with an oblique cylindrical tubule of the same length, and numerous small
pores. Thorax conical, one-fourth as long as the shell, with eight transverse rows of small pores.
Abdomen with numerous prominent, spirally convoluted ribs, and spiral rows of pores between
them. The first abdominal joint is from two to three times as long as each of the six following joints.
Abdominal pores larger, roundish, disposed in eleven transverse rows. Four rows in the first
abdominal joint, one row in each of the five following, and two rows hi the last joint. Mouth
slightly constricted, two-thirds as broad as the shell.

Dimensions. — Length of the shell (with nine joints) 017, cephalis 0'02, thorax 0'04, abdomen
Oil ; breadth 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms ; also fossil in Barbados.

Genus 650. Lithocampe,1 Ehrenberg, 1838, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 128 (sensu emendato).

Definition. — S tichocorida (vel Stichocyrtida eradiata aperta) with ovate or
spindle-shaped shell, the mouth of which is constricted, but not prolonged into a tube.
Cephalis without horn and tube.

1 Lithocampe = Stone-caterpillar ; *i'$o;, axft-rrn.

1502 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Lithocampe is the oldest of all " Polycystina," being founded by Ehren-
berg in 1838 upon Lithocampe radicula. Afterwards numerous other species, which
belong to very different genera, were described by him. In 1862 I attempted to give
a more strict definition of this genus in my Monograph (p. 312 to 315), and separated
it from the closely allied and often confounded Eucyrtidium by the absence of a
cephalic horn. The great number of species afterwards discovered leads to the stricter
definition given above.

Subgenus 1. Lithocampula, Haeckel.

Definition. — All joints of the shell (except often the first) are equal or nearly
equal in length.

1. Lithocampe eupora, Haeckel.

Eucyrtidium euporum, Ehrenberg, 1872, Abhandl. d. k. Akacl. d. Wiss. Berlin, p. 291, Taf. iv. iig. 30.

Shell smooth, ovate or subconical, with three deep strictures. Four joints equal in length,
gradually increasing in breadth, each with three transverse rows of regular, circular, hexagonally-
framed pores ; the fourth joint is the broadest. Mouth little constricted, of the same breadth as
the third joint.

Dimensions. — Length of the shell (with four joints) 0'08 ; length of each joint 0'02, greatest
breadth 0'06.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms; North Atlantic, depth 3600
fathoms (Morse).

2. Lithocampe platycephala, Haeckel.

Eucyrtidium platycephalum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, pp. 145,
293, Taf. iii. fig. 16.

Shell smooth, subconical or slenderly ovate, with three slight strictures. Four joints equal in
length, slightly increasing in breadth towards the mouth. The hemispherical cephalis with longi-
tudinal ribs and irregular pores, each of the three other joints with four transverse rows of regular,
circular pores. Mouth strongly constricted, half as broad as the third and fourth joints.

Dimensions. — Length of the shell (with four joints) 012 ; length of each joint O'OS, greatest
breadth 0'06.

Habitat. — North Atlantic, depth 3600 fathoms (Morse).

3. Lithocampe nereidum, Haeckel.

Lithocampe nereidum, Haeckel, 1862, Monogr. d. Eadiol., p. 319.

Eucyrtidium nereidum, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. "Wiss. Berlin, p. 242 ;
Mikrogeol., Taf. xxxv. B, 6, fig. 22.

Shell smooth, slenderly ovate, with four deep strictures. Five joints equal in length, the fourth
being the broadest. Each joint with three transverse rows of small, regular, circular pores (some-

REPORT ON THE RADIOLARIA. 1503

times in the fourth joint there are four rows). Mouth constricted, half as broad as the fourth joint.
(In Ehrenberg's figure all five joints are delineated, but the greater part of the hemispherical
cephalis is broken oft'.)

Dimensions. — Length of the shell (with five joints) 01, of each joint 0'02 ; breadth of the fourth
joint 0-05.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Lithocampe radicula, Ehrenberg.

Lithocampe radicula, Ehrenberg, 1838, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 130, Taf. iv.
fig. 11.; Mikrogeol., 1854, Taf. xxii. fig. 23ce.

Shell smooth, spindle-shaped, with five sharp strictures. Six joints equal in length, each with
four transverse rows of regular, circular, double-edged pores. The third and fourth joints are the
broadest, and equal. The constricted mouth is not broader than the hemispherical cephalis, scarcely
one-fourth as broad as the third and the fourth joints. This remarkable species is the oldest
known skeleton of a Radiolarian, a figure of it being given in 1838, loc. cit. (compare my Mono-
graph, 1862, p. 3, 4, 331). But this figure of Ehrenberg is not quite accurate, and differs from
other figures of the same species, which he afterwards (1854) published in his Mikrogeologie (loc.
tit.}. The best of these is fig. 23a in pi. xxii., and is identical with the typical form (common in
Barbados), and according to this I have here framed my description. The sixth joint possesses a
distinct (though small) terminal mouth ; when this becomes closed, the species passes over into
Stichocapsa radicula.

Dimensions. — Length of the shell (with six joints) 018, length of each joint (on an average)
0'03 ; breadth of the third and fourth joints O'OS, of the second and fifth 0-06 of the terminal mouth
and the cephalis 0'03.

Habitat. — Fossil in Tertiary rocks of Barbados.

5. Lithocampe ventricosa, Haeckel.

Dictyomitra ventricosa, Stohr, 1880, Palseontogr., vol. xxvi. p. 102, Taf. iii. fig. 25,

Shell ovate, with six slight strictures. Seven joints nearly equal in length, each with four (or
sometimes three or five) transverse rows of small, regular, circular pores, in the last joint the pores
are larger. The fourth and fifth joints are the broadest, and are twice as broad as the constricted
mouth.

Dimensions. — Length of the shell (with seven joints) 013 to 014 ; length of each joint 0-0l7 to
0'02, greatest breadth 0'083, mouth 0'04.

Habitat. — Fossil in Tertiary rocks of Sicily ; Grotte, Caltanisetta.

6. Lithocampe fusiformis, n. sp.

Shell smooth, spindle-shaped, decreasing uniformly towards the two blunt poles, with eight or nine
sharp strictures, and nine or ten joints of equal lengths, each with four transverse rows of regular,

1504 THE VOYAGE OF H.M.S. CHALLENGER.

hexagonal pores. The fourth and fifth joints are the broadest. The constricted mouth is twice as
broad as the hemispherical cephalis, half as broad as the fourth joint.

Dimensions. — Length of the shell (with ten joints) 0'2, of each joint O02 ; breadth of the fourth
joint 0-06, mouth 0'03.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Subgenus 2. Lithocampium, Haeckel, 1881, Prodromus, p. 437.
Definition. — The joints of the shell are very different in length.

7. Lithocampe ovata, n. sp. (PL 77, fig. 1).

Shell smooth, urceolate or ovate, with three sharp strictures. Four joints of different lengths,
having the proportion 1:2:2:6. The fourth joint is inflated and the broadest. The mouth is con-
stricted, short, tubular, of the same breadth as the hemispherical cephalis. Pores small, circular,
in regular transverse rows ; four rows in the first, four in the second, two in the third, and five in
the fourth joint. The middle stricture is crossed by longitudinal ribs.

Dimensions. — Length of the shell (with four joints) O'll. Length of the single joints, a O'Ol,
I 0-02, c 0-02, d 0-06 ; greatest breadth 0-055.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

8. Lithocampe aquilonaris, Haeckel.

Lithocampe aquilonaris, Haeckel, 1862, Monogr. d. Radiol., p. 317.

Eucyrtidium aquilonare, Bailey, 1856, Amer. Journ. Sci. and Arts, vol. xxii. p. 4, pi. i. fig. 9.

Shell smooth, subconical, with three distinct strictures. Four joints of different lengths, having
the proportion 3:1:3:4. The fourth joint is the broadest, suddenly constricted, with a short tubular
mouth of half the breadth. Pores subregular, circular, in transverse rows ; three rows in the first
joint, two in the second, four in the third, and three in the fourth joint.

Dimensions. — Length of the shell (with four joints) Oil. Length of the single joints, a 0'03,
6 O'Ol, c 0-03, d 0-04; breadth 0'06.

Habitat. — North Pacific, Kamtschatka (Bailey), Station 241, depth 2300 fathoms.

9. Lithocampe quadrarticulata, Haeckel.

Lithocampe quadrarticulata, Haeckel, 1862, Monogr. d. Radiol., p. 319.

Eucyrtidium quadrarticulatum, Ehrenborg, 1861, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 299.

Shell smooth, spindle-shaped, with three deep strictures. Four joints of different lengths =
1:3:4:3. The third joint is the broadest, being twice as broad as the constricted mouth of the
fourth joint. Pores small, regular, circular, in transverse rows ; two being in the first, three in the
second, four in the third, three in the fourth joint.

REPORT ON THE 'RADIOLARIA. 1505

Dimensions. — Length of the shell (with four joints') Oil. Length of the single joints, a 0'015,
I 0-03, c 0-04, d 0-025 ; greatest breadth 0'05.

Habitat. — North Atlantic (Greenland, depth 1600 fathoms, Ehrenberg), Station 64, surface.

10. Lithocampe multiseriata, Haeckel.

Eucyrtidium multiseriatum, Ehrenberg, 1872, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
page 293, Taf. vii. fig. 9.

Shell smooth, spindle-shaped, or slenderly ovate, with three sharp strictures. Four joints of
different lengths = 3:4:5:10. The third and fourth joints nearly equal in breadth, and twice as
broad as the hemispherical cephalis. The truncate mouth is slightly constricted. Pores very small
and numerous, in regular transverse rows. Three or four rows in the first, five or six in the second,
seven or eight in the third, and fifteen to twenty in the fourth joint.

Dimensions. — Length of the shell (with four joints) Oil. Length of the single joints, a 0'015,
b 0-02, c 0-025, d O'Oo ; breadth 0'045.

Habitat. — Tropical Pacific (Philippine Sea, Ehrenberg), Stations 206, 224, 266, in various
depths.

11. Liihocarmpe diploconus, n; sp. (PL 77, fig. 3).

Shell rough, doubly conical, with three distinct strictures. Four joints of different lengths =
2:5:5:8. The third joint is the broadest. The three first joints form together a broad cone, and
the fourth an inverse truncate cone ; the latter is distinguished by convergent longitudinal ribs.
Pores regular, circular, alternating with the ribs in the fourth joint. Truncate mouth hyaline, half
as broad as the third joint.

Dimensions. — Length of the shell (with four joints) 0'2. Length of the single joints, a 0'02, b 0-05,
c 0'05, d 0'08 ; breadth (in the middle part) 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

12. Lithocampe diaphana, Haeckel.

Eucyrtidium diaphanum, Ehrenberg, 1872, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 309.

Shell smooth, hyaline, spindle-shaped, decreasing uniformly towards both poles, with three
distinct strictures. Four joints of different lengths ; the second and third equal in breadth, twice as
broad and three times as long as the first and the • fourth. Pores very small and scarce, in
transverse interrupted rows, commonly two rows in the first, two or three in the second, three
or four in the third, and only one in the last joint. Mouth constricted, two-thirds as broad as
the fourth joint.

Dimensions. — Length of the shell (with four joints) 013. Length of the single joints, a 0-015,
b 0'05, c 0-05, d 0'015 ; breadth (in the middle part) 0'06, mouth 0'02.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 189

1506 THE VOYAGE OF H.M.S. CHALLENGER.

13. Lithocampe hispida, Haeckel.

Lithocampe hispida, Haeckel, 1862, Monogr. d. Eadiol., p. 318.

Eucyrtidium hispidum, Ehrenberg, 1861, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 298 ;
Abhandl. d. k. Akad. d. Wiss. Berlin, 1872, p. 291, Taf. ii. fig. 19.

Shell thorny, slenderly ovate, or nearly spindle-shaped, with four sharp strictures. Five joints
of different lengths = 3:3:4:6:4. The fourth joint is the broadest, and nearly twice as broad as
the constricted mouth. Pores small, circular, separated by longitudinal, spiny ribs, regularly dis-
posed in transverse rows ; three rows in the first and second, four rows in the third and fifth, six
rows in the fourth joint.

Dimensions. — Length of the shell (with five joints) 01. Length of the single joints, a 0'015,
& 0-015, c 0-02, d 0-03, e 0'02 ; greatest breadth 0'05.

Habitat. — Arctic Ocean (in different depths), Ehrenberg.

14. Lithocampe tumidula, Haeckel.

Lithocampe tumidula, Haeckel, 1862, Monogr. d. Radiol., p. 318.

Eucyrtidium tumidulum, Bailey, 1856, Amer. Journ. Soi. and Arts, vol. xxii. p. 5, pi. i. fig. 11.

Eucyrtidium tumidulum, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 293,

Taf. ii. fig. 12.

1 Eucyrtidium increscens, Ehrenberg, 1861, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 299.
? Lithocampe increscens, Haeckel, 1862, Monogr. d. Eadiol., p. 318.

Shell smooth, nearly spindle-shaped, with four sharp strictures, very similar to the preceding in
size and form. It differs in the smooth surface, the absence of longitudinal ribs, and the unequal
size of the pores, which form four transverse series in each joint, and are much larger in the
broadest (fourth) joint. Proportion of the five joints := 2 : 2 : 3 : 5 : 4.

Dimensions. — Length of the shell (with five joints) 01. Length of the single joints, a 0'012,
b 0-012, c 0-02, d 0'03, e 0-025 ; greatest breadth 0'05.

Habitat. — Cosmopolitan ; Atlantic, Pacific ; many stations, in different depths.

15. Lithocampe heteropora, Haeckel.

Lithocampe heteropora, Haeckel, 1862, Monogr. d. Radiol., p. 317.

Eucyrtidium heteroporum, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 242.

Shell smooth, subconical, obtuse, with four distinct strictures. Five joints of different lengths =
2:4:3:3:2. The fourth joint is the broadest. Mouth slightly constricted. Pores regular,
circular, in the second joint much 1'arger than in the four others, disposed in transverse series ;
two rows in the first and fifth, three rows in the second, four rows in the third and fourth joints.

Dimensions. — Length of the shell (with five joints) 014. Length of the single joints, a 0-02,
b 0-04, c 0-03, d 0'03, e 0'02 ; greatest breadth 0'07.

Habitat. — North Atlantic (depth 2000 fathoms, Ehrenberg), Canary Islands, surface, Haeckel.

REPORT ON THE RADIOLARIA. 1507

16. Lithocampe meta, Stohr.

Lithocampe meta, Stohr, 1880, Palsontogr., vol. xxvi. p. 103, Taf. iv. fig. 4.

Shell rough, subconical, obtuse, with four slight strictures. Five joints of different lengths =
2:4:5:4:2. The fourth joint is the broadest, and three times as broad as the constricted mouth.
Pores, small, regular, circular, quincuncially disposed, equal in size ; two transverse rows in the
first and fifth, five rows in the second and fourth, six rows in the third joint.

Dimensions. — Length of the shell (with five joints) 014. Length of the single joints, a 0'017,
b 0-033, c 0-04, d 0'033, e O'OlV ; greatest breadth 0-083.

Habitat. — Fossil in Tertiary rocks of Sicily, Grotte (Stohr), Caltanisetta (Haeckel).

17. Lithocampe urceolata, n. sp. (PI. 77, fig. 2).

Shell rough, wide, urceolate, without external strictures, but with four internal septal rings
(not visible in the figure), each of which contains an internal circle of horizontal pores. Five joints
of different lengths = 2:3:6:4:2. The third joint is the broadest, and three times as broad as the
constricted mouth. Pores of very different sizes, irregular, roundish, with prominent polygonal
frames. A very remarkable species.

Dimensions. — Length of the shell (with five joints) 017. Length of the single joints, a 0'02,
b 0-03, c 0-06, d 0'04, e 0'02 ; greatest breadth 013.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

18. Lithocampe clava, Ehrenberg.

Lithocampe clava, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 66, Taf. iv. fig. 2.

Shell smooth, club-shaped, or slenderly ovate, with five internal septal rings. Six joints of very
different lengths = 5:2:3:4:5:18. The sixth joint is the broadest, and as long as the five others
together. Pores small, circular, in the basal half of the last joint irregular and larger. Constricted
mouth as broad as the subspherical, hyaline cephalis.

Dimensions. — Length of the shell (with six joints) 015. Length of the single joints, a 0'02,
b 0-011, c 0-013, d 0-016, e 0-02,/0'07.
Habitat. — Fossil in Barbados.

19. Lithocampe hexacola, n. sp. (PI. 79, fig. 7).

Shell smooth, nearly spindle-shaped, without external strictures, but with five internal septal
rings. Six joints of different lengths = 4:8:5:5:5:10. The fourth joint is the broadest, and four
times as broad as the constricted mouth. Pores subregular hexagonal, or irregular polygonal, with
thin bars.

Dimensions. — Length of the shell (with six joints) 018, greatest breadth 0'09. Length of the
six joints, a 0'02, I 0'04, c, d, and e each 0'025, / 0'05.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

1508 THE VOYAGE OF H.M.S. CHALLENGER.

20. Lithocampe heptacola, n. sp. (PL 79, fig. 8).

Shell smooth, subcylindrical, constricted at both poles, with six distinct strictures. Seven
joints of different lengths, the five abdominal joints nearly equal, each half as long as the hemi-
spherical, vaulted thorax, and twice as long as the subspherical, small cephalis. Mouth constricted,
with a short, tubular, hyaline peristome (like an eighth joint without pores), about one-third as broad as
each of the four middle joints. Pores subregular hexagonal, or irregular polygonal, with thin bars.

Dimensions. — Length of the shell (with seven joints) 0'24, greatest breadth 0'09. Length of
the cephalis 0'02, thorax 0'06, each of the four following joints 0'03, of the last joint 0'04.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

21. Lithocampe octocola, n. sp. (PL 79, fig. 6).

Shell smooth, subcylindrical, thick-walled, constricted at both poles, without distinct, external
strictures, but with seven internal septal rings. Eight joints of different lengths ; four joints (the
second to the fifth) being about twice as long as the four others (the first and the three last).
The constricted mouth only one-third as broad as the four middle joints. Pores small and
numerous, subregular, circular.

Dimensions. — Length of the shell (with eight joints) 019, breadth 0'09. Length of the second
to the fifth joints, each 0'03 ; length of the four other joints, each about 0'016.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

22. Lithocampe polycola, n. sp.

Shell smooth, subcylindrical, constricted at both poles, with twelve to fifteen distinct strictures.
Fourteen to sixteen joints of- different lengths. Cephalis flat, cap-shaped, hyaline, without pores.
Thorax nearly hemispherical, with three transverse rows of small circular pores. Each following
joint (each abdominal joint) only with a single row of small pores. The constricted mouth of the
last joint only one-third as broad as the middle part of .the shell. (Very similar to Lithomitra
eruca, PL 79, fig. 3.)

Dimensions. — Length of the shell (with sixteen joints) 0'3, breadth 0'08. Length of the
cephalis 0'02, thorax 0'06, each of the following joints 0'015, last joint 0-025.

Habitat. — Tropical Pacific, Station 224, depth 1850 fathoms.

Genus 651. Spirocyrtis,1 Haeckel, 1881, Prodromus, p. 438.

Definition. — Stich ocor id a (vel Stichocyrtida eradiata aperta) with spirally-
arranged constrictions on the shell. Cephalis with a horn.

The genus Spirocyrtis and the following closely allied genus Spirocampe differ from
the other Stichocorida (and also from nearly all C y r t o i d e a) in a very remarkable

1 Spirocyrtis = Spiral basket ; axtioa, nvfri's.

REPORT ON THE RADIOLARIA. 1509

•

character. The annular constrictions of the multiarticulate shell and the corresponding
internal annular septa are here not separated, and do not lie in parallel, transverse planes
(as usually happens), but they are all or partly connected in the form of an ascending spiral,
so that the joints are not perfectly separated. An irregularity or asymmetry of growth
on the different sides of the shell is probably the cause of this strange, spiral structure.

Subgenus 1. Spirocyrtidium, Haeckel.

Definition. — Shell conical, gradually dilating towards the wide open terminal
mouth.

1. Spirocyrtis scalaris, n. sp. (PI. 76, fig. 14).

Shell conical, gradually dilating towards the wide open mouth, with ten to twelve spiral
convolutions, which correspond to the same number of short and broad chambers or joints,
gradually increasing in breadth ; all joints form together a spirally winding staircase. The length
or height of the single joints or stairs is about equal, and each bears four or five transverse rows of
small, square pores. Cephalis flat, cap-shaped, with two or three short divergent horns.

Dimensions. — Length of the shell (with ten joints or turnings) 016, length of each joint (on
an average) O'OIG ; breadth of the third joint 0'04, of the fifth joint 0'07, of the tenth joint 01.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

2. Spirocyrtis cornutella, n. sp. (PI. 76, fig. 13).

Shell conical, gradually dilating towards the wide mouth, similar to the preceding, but
differing in the curved axis, and the broader and shorter joints, each of which bears only two
or three transverse rows of square pores. The turnings of the staircase are not so sharp, nor
so distinct, as in the preceding species. Cephalis with a single short horn.

Dimensions. — Length of the shell (with eight joints) 01 ; breadth of the fourth joint 0'05, of
the eighth joint 0'08.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

Subgenus 2. Spirocyrtoma, Haeckel.

Definition. — Shell ovate, or nearly spindle-shaped, more or less tapering towards the
narrower, somewhat constricted mouth.

3. Spirocyrtis holospira, n. sp. (PI. 76, fig. 16).

Shell subovate, twice as long as broad, without external strictures, but with an internal regularly
descending spiral septum, which separates seven to nine broad joints of nearly equal lengths ; the

1510 THE VOYAGE OF H.M.S. CHALLENGER.

9

first and second joints together are conical, and about as long as each of the following joints. Cephalis
small, hemispherical, with a thick pyramidal horn of the same length. The fifth joint is the
broadest, the truncate mouth is slightly constricted (in the specimen figured it is broken off).
Pores regular, circular, quincunciaL

Dimensions.— Length of the shell (with eight joints) 0'2, breadth O'l ; length of each joint,
about 0'03.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Spirocyrtis hemispira, n. sp.

Shell slender, nearly spindle-shaped, three times as long as broad, without external strictures,
but with ten to eleven internal septa. The five or six upper of these are perfectly separate, com-
plete parallel rings ; the five or six lower are spirally connected. The eleven or twelve joints
gradually taper in length and breadth, from the broadest middle towards the two constricted ends
of the shelL The middle (fifth or sixth) joint is the broadest, and is three to four times as
broad as the constricted mouth. Cephalis small, hemispherical, with a conical horn of the same
length. Pores regular, circular, hexagonally framed.

Dimensions. — Length of the shell (with twelve joints) 0'25, breadth 0'09 ; length of the middle
joint 0-03.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

5. Spirocyrtis merospira, n. sp. (PI. 76, fig. 15).

Shell ovate, with six to eight slight strictures, twice as long as broad. The three or four upper
joints are perfectly separated by annular septa, the three or four lower joints connected by an
internal spiral septum. The spiral line is often more or less irregular or interrupted (as is also the
case in the specimen figured). Mouth rather wide. Pores small, subregular, circular. A rather
variable species.

Dimensions. — Length of the shell (with eight joints) 0'2, breadth O'l.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

6. Spirocyrtis diplospira, n. sp. (PL 76, fig. 17).

Shell slender, ovate, with seven to eight slight strictures. All eight or nine joints are con-
nected by an internal double spiral septum, the first spiral beginning from the ventral side, the
second from the dorsal side of the collar stricture. Length and breadth of the single joints
rather variable and irregular ; the broadest joint is commonly the fifth. Mouth more or less con-
stricted. Pores subregular, circular. This remarkable species differs from all other Cyrtoidea
by the double spiral septum of the joints.

Dimensions. — Length of the shell (with eight joints) 0'2, breadth O'l.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

REPORT ON THE RADIOLARIA. 1511

Genus 652. Spirocampe? Haeckel, 1881, Prodromus, p. 438.

Definition. — S tichocorida (vel Stiehoeyrtida eradiata aperta) with spirally
arranged constrictions on the shell. Cephalis without horn.

The genus Spirocampe has the same peculiar spiral structure of the shell as the pre-
ceding Spirocyrtis, and differs from it only in the absence of a cephalic horn. It exhibits,
therefore, the same relation to the latter as the similar Lithocampe bears to
Eucyrtidium.

1. Spirocampe callispira, n. sp. (PI. 76, fig. 11).

Shell ovate, smooth, with six joints, connected in the form of a complete winding staircase. All
the windings are nearly at equal distances ; each bears one row of large roundish pores, enclosed by
two rows of smaller pores. Cephalis hemispherical, of about the same breadth as the constricted,
short tubular mouth.

Dimensions. — Length of the shell (with six joints) 015, breadth 0'09 ; mouth 0'03 diameter.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

2. Spirocampe allospira, n. sp. (PL 76, fig. 12).

Shell subcylindrical, or nearly spindle-shaped, smooth, very thick-walled, with eight joints
alternately longer and shorter, and connected in the form of an irregular spiral. The distance
between the windings is very variable. Pores small, regular, circular. Cephalis hemispherical, of
about the same size as the short tubular mouth.

Dimensions. — Length of the shell (with eight joints) 0'2, breadth 0'08 ; mouth 0'03 diameter.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

3. Spirocampe polyspira, n. sp.

Shell cylindrical, rough, with twelve joints nearly equal in length, connected in the form of a
regular, complete spiral. All windings are at the same distance. Pores regular, circular, three rows on
each turning. Cephalis flat, cap-shaped, half as broad as the slightly constricted, not tubular mouth.

Dimensions. — Length of the shell (with twelve joints) 0'24, breadth 0'07 ; mouth O'Oo diameter.

Habitat. — Central Pacific, Station 27l, depth 2425 fathoms.

Subfamily 2. STICHOCAPSIDA, Haeckel, 1881, Prodromus, p. 439.

Definition. — L ithocampida with the terminal mouth of the shell fenestrated
(vel Stiehoeyrtida eradiata clausa).

1 Spirocampe = Spiral caterpillar ;

1512 THE VOYAGE OF H.M.S. CHALLENGER.

.

Genus 653. Cyrtocapsa,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — Stichocap sida (vel Stichocyrtida eradiata * clausa) with an apical
horn on the cephalis, without basal terminal spine.

The genus Cyrtocapsa and the two following genera represent together the small sub-
family of Stichocapsida, or of those Cyrtoidea in which the many-jointed shell bears
no radial appendages, and the terminal mouth is closed by a lattice-plate. They have been
derived from the Stichocorida by development of such a closing plate. Cyrtocapsa bears
an apical horn on the cephalis, and may be derived therefore directly from Eucyrtidium.

Subgenus 1. Cyrtocapsella, Haeckel.

Definition. — Shell with three annular strictures (or internal septa) and four distinct
joints.

1. Cyrtocapsa tetrapera, n. sp. (PI. 78, fig. 5).

Shell rough, pear-shaped, with three deep strictures. The three first joints are of equal lengths,
and each half as long as the hemispherical fourth joint. Cephalis subspherical, with an oblique
conical horn of the same length. The third joint is the broadest, three times as broad as long.
Pores regular, circular.

Dimensions. — Length of the shell (with four joints) 015, breadth 0'09 ; length of each of the
three first joints 0'03, of the last 0'06.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Cyrtocapsa compacta, n. sp. (PI. 77, fig. 8).

Eucyrtidium compadum, Haeckel, 1878, Atlas, loc. cit.

Shell rough, pear-shaped, with three slight strictures. The hemispherical cephalis bears a thick
pyramidal spine of the same length, and is half as long as the second and the third joints, one-
third as long as the hemispherical fourth joint. The third joint is the broadest, three times as
broad as- long. Pores subregular, circular. In the centre of the basal pole is one larger pore, the
remnant of the constricted mouth of Ewyrtidium.

Dimensions. — Length of the shell (with four joints) 016, breadth 012. Length of the single
joints, a 0'02, b 0"04, c 0'04, d 0'06.

Habitat. — Western Tropical Pacific, Station 206, depth 2100 fathoms.

1 Oyrtocapsa= Basket-capsule ; xvfrc;, x*^*.

REPORT ON THE RADIOLARIA. 1513

3. Cyrtocapsa inftata, n. sp.

Shell spiny, pear-shaped, with three deep strictures. The inflated third joint is twice as long
as the second and fourth joints, and three times as long as the hemispherical cephalis, which bears a
large conical horn of three tunes the length. Fourth joint flat, vaulted, inversely cap-shaped. The
third joint is the broadest, being twice as broad as long. Pores regular, circular, double-contoured.

Dimensions. — Length of the shell 014, breadth Oil. Length of the single joints, a 0'02, 1 0'03,
c 0-06, d 0-03.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

4. Cyrtocapsa pyrum, n. sp. (PI. 78, fig. 8).

Shell thorny, pear-shaped, without external strictures, but with three internal annular septa.
Length of the four joints = 2:5:6:7. The fourth joint is the broadest, being about twice as broad
as long, and hemispherical. The small subspherical cephalis bears a stout conical horn of the
same length. Pores large, regular, circular.

Dimensions. — Length of the shell (with four joints) 0'2, breadth 012. Length of the single
joints, a 0'02, b 0'05, c 0'06, d 0'07.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

5. Cyrtocapsa cornuta, n. sp. (PI. 78, fig. 9).

Shell rough, very thick-walled, nearly pear-shaped, with three annular strictures ; the second of
which is very sharp, the first and third slight. Length of the four joints = 3:4:5:6. The third
joint is the broadest, being about twice as broad as long ; the fourth joint is hemispherical. Cephalis
subspherical, with a large, conical, curved horn of twice the length. Pores regular, circular, hexa-
gonally framed.

Dimensions. — Length of the shell (with four joints) 018, breadth 012. Length of the single
joints, a 0'03, b 0'04, c O'Oo, d 0"06.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

6. Cyrtocapsa diploconus, n. sp. (PI. 78, fig. 6).

Shell rough, doubly conical, with three annular septa. Length of the four joints = 3:4:4:8.
The third joint is the broadest, two and a half times as broad as long ; the fourth is inversely conical,
acute. Cephalis hemispherical, with a pyramidal horn of the same length. Pores irregular, roundish.

Dimensions. — Length of the shell (with four joints) 019, breadth 01. Length of the single
joints, a 0'03, b 0'04, c 0'04, d 0'08.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

(ZOOL. CHALL. EXP. — PABT XL. — 1886.) El 190

1514 THE VOYAGE OF H.M.S. CHALLENGER.

7. Cyrtocapsa fusulus, n. sp. (PL 78, fig. 7).

Shell smooth, spindle-shaped, with three distinct strictures. Length of the four joints =
1:1:4:3. The third joint is the broadest, somewhat longer than broad. The fourth joint is
inversely conical Cephalis hemispherical, with a coronal of large, ovate pores, and a pyramidal,
sulcate, oblique horn of twice the length. Pores regular, circular.

Dimensions. — Length of the shell (with four joints) 018, breadth 0-07. Length of the single
joints, a 0'02, b 0'02, c 0'08, d 0'06.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

Subgenus 2. Cyrtocapsoma, Haeckel.
Definition. — Shell with four or more annular septa, and five or more joints.

8. Cyrtocapsa incrassata, Haeckel.

Eucyrtidium incrassatum, Stohr, 1880, Palaeontogr., vol. xxvi. p. 105, Taf. iv. fig. 9.

Shell rough, spindle-shaped, with four annular septa. Length of the five joints = 2:3:4:4:4.
The third joint is the broadest, nearly three times as broad as long. The fourth joint is inversely
conical, acute. Cephalis small, spherical, with two short, conical, divergent horns. Pores small,
regular, circular.

Dimensions. — Length of the shell (with five joints) 017, breadth Oil. Length of the single
joints, a 0'015, b 0'035, c 0'04, d 0'04, e 0'04.

Habitat. — Fossil in Tertiary rocks of Sicily, Grotte.

9. Cyrtocapsa costata, n. sp.

Shell smooth, spindle-shaped, twice as long as broad, with numerous longitudinal ribs, and
four annular septa. Length of the five joints = 1:4:3:2:8. The third joint is the broadest.
Fourth joint inversely conical, acute. Cephalis small, hemispherical, with a small conical horn.
Pores regular, circular.

Dimensions. — Length of the shell (with five joints) 018, breadth 0'09. Length of the single
joints, a O'Ol, b 0'04, c 0'03, d 0'02, e 0'08.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

10. Cyrtocapsa colatractus, n. sp.

Shell smooth, spindle-shaped, with eight internal annular septa (without external stricture).
All nine joints are nearly equal in length, the first somewhat shorter, the last longer. The fourth
joint is the broadest, four times as broad as long. Last joint inversely conical, blunt. Cephalis
subspherical, with a conical horn of the same length. Pores small and numerous, regular,
circular.

REPORT ON THE RADIOLARIA. 1515

Dimensions. — Length of the shell (with nine joints) 0'22, breadth O'l ; length of the cephalis
0-015, of the last joint, 0-03, of each of the seven other joints, 0'022 to 0'028.
Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

11. Cyrtocapsa chrysalidium, n. sp. (PI. 76, fig. 9).

Shell rough, nearly spindle-shaped, with seven distinct strictures. Length of the eight joints =
4:6:11:8:5:5:4:3. The third and fourth joints are the broadest. The last joint is small,
inversely cap-shaped. Cephalis subspherical, with an oblique, dentate horn of the same length.
Pores very numerous, subregular, circular.

Dimensions. — Length of the shell (with eight joints) 0'23, breadth O'l. Length of the single
joints, a 0'02, 6 0'03, c 0'055, d 0'04, e 0'025, / 0'025, g 0'02, h 0'015.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 654. Stichocapsa,1 Haeckel, 1881, Prodromus, p. 439.

Definition. — S tichocapsida (vel Stichocyrtida eradiata clausa) without apical
horn, and without basal spine.

The genus Stichocapsa differs from the preceding Cyrtocapsa in the absence of
an apical horn, and bears therefore to it the same relation as Lithocampe does to
Eucyrtidium. It may be derived either from Cyrtocapsa by loss of the horn, or from
Eucyrtidium by closure of the terminal mouth.

1. Stichocapsa tetracola, n. sp. (PI. 78, fig. 1).

Shell smooth, spindle-shaped, half as broad as long, with three slight strictures. Length of the
four joints = 3:4:4:11. The fourth joint is the broadest, inversely conical, with acute basal pole.
Pores subregularly square in the second and third joints, more irregular in the fourth joint.

Dimensions. — Length of the shell (with four joints) O'll. Length of the single joints, a 0'015,
J 0-02, c 0-02, d 0-055 ; breadth 0'055.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

2. Stichocapsa quadrigata, n. sp. (PI. 78, fig. 3).

Shell smooth, pear-shaped, half as broad as long, with three deep strictures. Length of the
four joints = 3:8:8:5. The second joint is the broadest. The fourth joint is scarcely larger
than the hemispherical cephalis, inversely conical, with blunt basal pole. Pores subregular, square,
in transverse rows, in the second and third joints of equal size, in the fourth smaller.

Dimensions. — Length of the shell (with four joints) 012. Length of the single joints, a O'Olo,
b 0-04, c 0-04, d 0-025; breadth 0'06.

Habitat. — Central Pacific, Station 270, depth 2925 fathoms.

1 Stichocapsa = Jointed capsule ;

1516 THE VOYAGE OF H.M.S. CHALLENGER.

3. Stichocapsa tricincta, n. sp. (PI. 78, fig. 2).

Shell smooth, spindle-shaped, twice as long as broad, with three deep strictures. Length of the
four joints = 2 : 5 : 5 : 10. The third joint is the broadest. Fourth joint inversely conical, with acute
basal pole. Cephalis small, subconical. Pores irregular, roundish, of very different sizes.

Dimensions. — Length of the shell Oil. Length of the single joints, a O'Ol, 6 0'025, c 0'025,
d 0-05 ; breadth 0-055.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

4. Stichocapsa subglobosa, n. sp.

Shell thorny, broad, pear-shaped, nearly spherical, almost as broad as long, with three internal
septal rings. Length of the four joints = 1:2:7:2. Cephalis small, subspherical. Thorax flat,
conical. Third joint very large, inflated, about twice as broad as the second and fourth joints. The
latter is flat, cap-shaped, with rounded basal pole. Pores regular, circular, hexagonally framed, in
the third joint twice as broad as in the second and fourth joints.

Dimensions. — Length of the shell 0'24. Length of the single joints, a 0'02, 5 0'04, c 014, d 0'04 ;
breadth 0'2.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

5. Stichocapsa compressa, Haeckel.

Lithocampe compressa, Stohr, 1880, Palasontogr., vol. xxvi. p. 103, Taf. iv. fig. 5.

Shell rough, broad, pear-shaped, almost as broad as long, with three internal septal rings.
Length of the four joints = 1:2:3:2. Cephalis very small, spherical. Thorax conical. The
third joint is the broadest, strongly inflated. The fourth joint (in the figure of Stohr broken off) is
in a well preserved specimen inversely hemispherical, with rounded basal pole. Pores very small,
regular, circular.

Dimensions. — Length of the shell 01. Length of the single joints, a 0'013, & 0'027, c 0'04,
d 0-022 ; breadth 0'08.

Habitat. — Fossil in Tertiary racks of Sicily ; Grotte, Caltanisetta.

6. Stichocapsa pyriformis, n. sp.

Shell rough, pear-shaped, about twice as long as broad, with three internal septal rings.
Length of the four joints = 2:5:2:9. Cephalis small, spherical, hyaline. Thorax conical. Third
joint very short and broad ; the fourth joint is the broadest, half as long as the shell, with an
inversely hemispherical basal pole. Pores subregular, circular, small and numerous, larger in the
basal third.

Dimensions. — Length of the shell 018. Length of the single joints, a 0-02, & 0'05, c 0'02, d 0'09 ;
breadth 01.

Habitat. — Fossil in Barbados.

REPORT ON THE RADIOLARIA. 1517

7. Stichocapsa monstrosa, n. sp. (PI. 78, fig. 4).

Shell tuberculate, twice as long as broad, irregular, horn-shaped or inversely conical, with
curved axis, and with three internal septal rings. Length of the four joints = 2:7:3:4.
Cephalis subspherical, with small, circular pores. The thorax is the broadest joint, half as long as
the shell. The fourth joint is small, inversely conical, with a blunt, curved, basal pole. Pores
irregular, roundish, partly double-contoured.

Dimensions. — Length of the shell (with four joints) 016. Length of the single joints, a 0'02,
5 0-07, c 0-03, d 0-04 ; breadth 0'08.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

8. Stichocapsa pentacola, n. sp. (PL 76, fig. 1).

Shell smooth, slender, pear-shaped, twice as long as broad, with four sharp strictures. Length
of the five joints =1:1:1:2:3. The three first joints are nearly equal in length, but increase in
breadth. The fifth joint is the broadest, nearly spherical, with rounded basal pole. Pores irregular,
roundish.

Dimensions. — Length of the shell (with five joints) 013. Length of the single joints, a 0'0l7,
b 0-017, c 0-017, d 0-028, e 0'05 ; breadth 0'07.

Habitat. — Central Pacific, Station 273, depth 2350 fathoms.

9. Stichocapsa hexacola, n. sp. (PI. 76, fig. 2).

Shell rough, slender, pear-shaped, twice as long as broad, with five internal septal rings. The
five first joints are nearly equal in length. The sixth joint is the broadest, half as long as the shell,
with a rounded, hemispherical basal pole. Pores small and numerous, subregular, circular, larger
in the inflated basal third.

Dimensions. — Length of the shell (with six joints) 0'2. Length of each of the first five joints
0-02, of the sixth joint 01 ; breadth 01.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms ; also fossil in Barbados.

10. Stichocapsa compacta, n. sp. (PI. 76, fig. 3).

Shell rough very thick-walled, slender, pear-shaped, twice as long as broad, without external
stricture, but with eight internal septal rings. The eight first joints, gradually increasing in
breadth, are nearly equal in length. The eighth joint is the broadest, and one-third as long as the
shell, inversely hemispherical. Pores small, circular, in the last joint larger.

Dimensions. — Length of the shell (with nine joints) 0'25. Length of each of the eight first joints
about 0-02, of the ninth joint 0'08 ; breadth 013.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms ; also fossil in Barbados.

1518 THE VOYAGE OF H.M.S. CHALLENGER.

11. Stichocapsa radicula, Haeckel.

Lithocampe radicula, Ehrenberg, 1838 (partim); Mikrogeol., 1854, Taf. xxii. fig. 23&. ?

Shell smooth, spindle-shaped, decreasing from the broader middle towards the two rounded
poles, with four or five slight strictures. All five or six joints nearly equal in length, the middle
(third and fourth) are the broadest. Pores subregular, circular. (To this species those forms of
Lithocampe radicula, Ehrenberg, must be referred, in which the basal opening is perfectly closed by
lattice-work. The other forms in which the basal mouth remains open, and which are connected
with the former by transitional forms, constitute the true type of the genus Lithocampe (page 1503).

Dimensions. — Length of the shell (with six joints) 0'12 to 0'15, breadth 0'06 to 0'07.

Habitat. — Fossil in Barbados.

12. Stichocapsa subligata, Haeckel.

Lithocampe subligata, Stb'hr, 1880, Palaeontogr., vol. xxvi. p. 102, Taf. iv. fig. 1.

Shell rough, subcylindrical, irregular, with seven slight strictures. All eight joints of slightly
different lengths, the third joint is the broadest ; the seventh joint is much broader than the sixth
and the eighth joints. The latter is inversely hemispherical. Cephalis very small, spherical.
Pores regular, circular, very small and numerous.

Dimensions. — Length of the shell (with eight joints) 0'24 ; length of the single joints (on an
average) 0'025 to 0-035, breadth 0'08.

Habitat. — Fossil in Tertiary rocks of Sicily (Grotte).

13. Stichocapsa paniscus, n. sp. (PI. 76, fig. 4).

Shell smooth, cylindrical, with a blunt, conical cephalis, and a hemispherical last joint, without
external strictures, but with seven or eight internal septa. Eight or nine joints nearly equal in
length, the second and the last somewhat longer. Pores circular, of unequal sizes.

Dimensions. — Length of the shell (with seven joints) 016 ; length of each joint (on an
average) 0'02 to 0'03, breadth 0'07.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

14. Stichocapsa cylindrica, n. sp.

Shell rough, cylindrical, four times as long as broad, with hemispherical cephalis and last joint,
without external stricture, but with ten or eleven internal septa. All eleven or twelve joints are
nearly equal in length, and are three times as broad as long. Only the flat cephalis is shorter, and
the vaulted last joint longer than each of the nine or ten other joints. Pores regular, circular.

Dimensions. — Length of the shell (with twelve joints) 0'24 ; length of each joint (on an
average) 0'02, breadth 0-06.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

REPORT ON THE RADIOLARIA. 1519

\

Genus 655. Artocapsa,1 Haeckel, 1881, Prodromus, p. 438.

Definition. — S tichocapsida (vel Stichocyrtida eradiata clausa) with an apical
horn on the cephalis, and a basal terminal spine on the last joint.

The genus Artocapsa differs from Cyrtocapsa, its ancestral form, by the development
of a vertical terminal spine, or a bunch of spines, on the base of the last joint, and
bears therefore to it the same relation as Rhopalatractus does to Rhopalocanium.

1. Artocapsa fusiformis, n. sp. (PI. 76, fig. 5).

Shell spindle-shaped, rough, with five slight strictures, decreasing uniformly from the broader
middle towards both poles, with a strong, pyramidal, terminal spine at each pole. Length of the
six joints = 2:5:3:3:2:5. Cephalis hemispherical, hyaline, without pores, its horn half as large
as the basal spine. Pores small and numerous, subregular, circular.

Dimensions. — Length of the shell (with six joints) 0'2, breadth 0'09. Length of the single
joints, a 0'02, 6 0'05, c 0'03, d 0'03, e 0'02, / 0'05.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Artocapsa spinosa, n. sp. (PI. 76, fig. 10).

Shell spindle-shaped, spiny, with five distinct strictures. Length of the six joints =
2:3:2:5:4:4. The fourth joint is the broadest, and much larger than the five other joints.
The first and the lact joints are- similar in size and form, hemispherical, armed with some larger,
irregular, conical spines. Pores irregular, roundish, of variable sizes.

Dimensions. — Length of the shell (with six joints) 0'2, breadth 0'09. Length of the single
joints, a 0'02, b 0'03, c 0-02, d 0'05, e 0'04, / 0'04.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

3. Artocapsa infraculeata, Haeckel.

Eucyrtidium infraculeatum, Stohr, 1880, Palseontogr., voL xxvi. p. 106, Taf. iv. fig. 13.

Shell subcylindrical, rough, with five annular septa. Length of the six joints = 2:3:4:4:4:3.
The third, fourth, and fifth joints are nearly equal in length and breadth, whilst the second and
sixth are cupola-shaped. The cephalis is very small, subspherical (regarded by Stohr as a " large
pore "), and bears a short conical horn. The last joint bears a bunch of basal spines.

Dimensions. — Length of the shell (with six joints) 0'2, breadth 0'09. Length of the cephalis
0'02, second and sixth joints 0'03, third, fourth, and fifth joints 0'04.

Habitat. — Fossil in Tertiary rocks of Sicily ; Grotte (Stohr), Caltanisetta ^Haeckel).

1 Artocapsa = Bread-shaped capsule ; Anas, xa-vj-c*.

1520 THE VOYAGE OF H.M.S. CHALLENGER.

4. Artocapsa quadricamera, n. sp.

Shell spindle-shaped, smooth, with three sharp strictures. Length of the four joints = 2:3:4:8.
The third joint is the broadest. The fourth joint is inversely conical, nearly as long as the three
other joints together, and bears a strong, conical, basal spine, of half the length. The cephalis is
small, subspherical, and bears a conical horn of the same length. Pores subregular, circular.

Dimensions. — Length of the shell (with four joints) 017, breadth 0'08. Length of the single
joints, a 0'02, b 0'03, c 0'04, d 0'08.

Habitat. — Fossil in Barbados.

5. Artocapsa armata, n. sp.

Shell slender, inversely ovate, spiny, with six deep strictures. Length of the seven joints =
2:4:6:5:4:3:2. The third joint is the broadest, inflated, and much larger than the four follow-
ing, which gradually decrease in size. The small, hemispherical cephalis bears a stout pyramidal
horn of twice the length. The last hemispherical joint is armed with a bunch of stout spines, one
of which is much the larger, and as long as the third joint. Pores irregular, roundish.

Dimensions. — Length of the shell (with seven joints) O26, breadth 012. Length of the single
joints, a 0'02, b 0'04, c 0'06, d 0'05, e 0'04, / 0'03, g 0'02.

Habitat. — Western Tropical Pacific, Station 225, depth 4575 fathoms.

6. Artocapsa octocamera, n. sp.

Shell subcylindrical, smooth, with seven internal annular septa. Five joints (the third to the
seventh) are nearly equal in size, while the second and eighth are cupola-shaped, somewhat longer.
The cephalis is smaller, with a conical horn of the same length. The last joint bears a bunch of
divergent, conical spines, of different lengths. Pores small, regular, circular.

Dimensions. — Length of the shell (with eight joints) 016, breadth 0'08. Length of the cephalis
0'016, second and eighth joints 0'033, each of the five other joints 0'022.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

7. Artocapsa elegans, n. sp. (PI. 76, fig. 8).

Shell spindle-shaped, smooth, with eight internal, broad, annular septa. The second and third
joints are the largest, the fourth and fifth of medium size, while the cephalis and the four last joints
are nearly equal in length, and much shorter. The third joint is the largest. The subspherical cephalis
bears a bristle-shaped horn of the same length, while the last joint is armed with a bunch of conical
spines. Pores small, in the upper half of the shell regular, hexagonal, in the lower half irregular.

Dimensions. — Length of the shell (with nine joints) 0'2, breadth 0'09. Length of the first and
the four last joints, each 0'014 ; of the fourth and fifth, each 0'02 ; of the third 0'04, second 0'05.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

REPORT OX THE RADIOLARIA. 1521

Legion IV. PH^EODARIA,
vel Cannopylea, vel Pansolenia (Pis. 99-128).

Phceodaria, Haeckel, 1879.
Tripylea, Hertwig, 1879.
Cannopylm, Haeckel, 1881.
Pansolenia, Haeckel, 1878.

Definition. — Radiolaria with a double membrane surrounding the central capsule,
which bears on one pole of the main axis a peculiar astropyle, or a tubular main-opening,
in the centre of a circular radiate operculum. Usually (but not constantly) a pair of
small, lateral, accessory openings (or parapylse) on the opposite pole of the main axis.
Extracapsulum constantly with a phseodium, or with a voluminous aggregation of peculiar
dark pigment bodies (phseodella) covering the astropyle of the central capsule. Skeleton
siliceous or silicated, always extracapsular, very rarely wanting. Fundamental form
very variable, originally monaxon, often dipleuric or bilateral.

The legion PH.EODARIA, or CANNOPYLEA, in the extent here defined, was constituted
by me in 1878, in my Protistenreich (p. 102) under the name PANSOLENIA. This
name was given on the supposition that the skeleton of these interesting Radiolaria is
always composed of hollow tubules, in contrast to that of the other Radiolaria, where it is
never tubular. But I was soon convinced that this supposition was erroneous, that in a
great part of the PANSOLENIA the skeleton is not composed of hollow tubules but of
solid bars, and that a constant, very characteristic, and never failing mark of this group
is to be found in the peculiar phseodium, a voluminous, constant, extracapsular pigment
body. Therefore, in 1879, I changed the name into PHCEODARIA, and having discovered
in the collection of the Challenger an astonishing number of new and wonderful types
of this group, I described, in a preliminary note on it, four different orders and ten families
with thirty-eight genera (Ueber die Phseodarien, eine neue Gruppe kieselschaliger mariner
Rhizopoden ; in Sitzungsberichte der Jenaischen Gesellschaft fur Medicin and Natur-
wissenschaft. Sitzung vom, 12th December 1879).

In the same year (1879), Richard Hertwig, in his excellent work entitled Der Organ-
ismus der Radiolarien, published the first accurate description of the intimate structure
of the soft body of the PANSOLENIA, and mainly of their central capsule ; and having
always observed, in the few representatives examined by him, three openings in
the capsule (one main-opening and two accessory openings), he called them TRIPYLEA
(loc. cit. p. 87), being guided by the erroneous supposition that these three openings are

(ZOOL. CHALL. EXP. PART XL. — 1886.) Rr 191

1522 THE VOYAGE OF H.M.S. CHALLENGER.

constant in all members of the group. But this is by no means the case. The two
accessory openings are completely absent in several families, whilst in others their
number is increased. A constant and very striking character, however, of all PH^EODARIA,
is the peculiar structure of their tubular main-opening, which I call astropyle, with its
radiate operculum and cannular proboscis. On account of this important and startling
characteristic I proposed in 1881 to call this group CANNOPYLEA. The two names
PHJEODARIA and CANNOPYLEA both express a very striking and quite constant character
of these curious Radiolaria, whilst the two names PANSOLENIA and TRIPYLEA are applicable
only to a part of the whole legion.

The history of our knowledge of the PELEODARIA is short, but very remarkable.
Although hundreds of species, many of them cosmopolitan, are distributed over all
oceans and all zones, although their size is in general much greater than that of the other
Radiolaria (usually 1 to 2 mm., often even 5 to 10 mm. or more), and although their form
and structure are usually striking, nevertheless the PH.EODARIA remained completely
unknown up to the year 1859. During that year I observed the first forms living in the
Gulf of Messina, and described and figured in 1862 in my Monograph five genera and
seven species, viz., (1) Aulacantha scolymantha (p. 263), (2) Tlialassoplancta cavispicula
(p. 261, now Cannobelos cavispicula), (3) Aulosphcera trigonopa, and Aulosphcera
elegantissima (p. 359), (4) Spongodictyum trigonizon (p. 459, now Sagoplegma trigonizon),
and (5) Ccelodendrum ramosissimum, and Ccclodendrum gracillimum (p. 361). I
recognised the structure of the three genera enumerated as 1, 3, and 5, as so remarkable
and so different from that of the other Radiolaria, that I founded three peculiar
families for them, the Aulacanthida, Aulosphaerida, and Ccelodendrida.

The first note on the numerous remarkable PH^ODARIA discovered by the Challenger,
and mainly on the large-sized inhabitants of the deep-sea, was published in 1876 by Dr.
John Murray, in his Preliminary Reports on Work done on Board the Challenger (Proc.
Roy. Soc., vol. xxiv., read March 16, 1876). He pointed out (loc. cit., p. 535), that the
tow-nets, sent down to a great depth (according to a new plan, adopted in April 1875)
brought up on every occasion a great many new and peculiar Rhizopods, which had
never been observed in the nets used near the surface. " The shells of all have an
exceedingly beautiful tracery, a fenestrated appearance often, which a closer examination
shows to be caused by pit-like depressions. Some have only one, others have several
openings, through which the sarcode flows. The sarcode of all these deep-sea Rhizopods
has many large black-brown pigment-cells. At times they come up with a good deal of
the sarcode outside of the shell ; and two specimens have been seen to throw out
elongated pseudopodia" (loc. cit., p. 536). Dr. John Murray distinguished at that time
not less than fifty species of these interesting deep-sea Rhizopods and called them
provisionally Challengerida ; a term which we retain here for the largest and most
characteristic family. He gave at the same time, in an accompanying plate (xxiv.), six

REPORT ON THE RADIOLARIA. 1523

figures of new PH^EODARIA, the names of which (as found by me in 1879 in the corres-
ponding preparations) are the following ; (l) Challengeria naresii, (2) Challengeria
aldrichii, (3) Bivalva compressa (now = Conchopsis compressa), (4) Tuscarora
belknapii, (5)' Challengeria circopora (now= Circoporus sexfurcus), and (6) Haeckeliana
porcellana. A great number of these Challengerida (twenty species) were afterwards
figured by Dr. John Murray in the Narrative of the Cruise of H.M.S. Challenger,
1885, vol. i. part 1, p. 226, PL A ; viz., fourteen species of Challengeria and six species
of Tuscarora.

The most important advance in the knowledge which we had of the peculiar
organisation of the PH^EODARIA, was made by the accurate description which Richard
Hertwig published, in 1879, of the intimate structure of their central capsule, and mainly
of its peculiar openings. He examined living at Messina the following three forms,
described in my Monograph; (l) Aulacantha scolymantha, (2) Aulosphwra elegantis-
sima, and (3) Ccelodendrum. ramosissimum. Besides, he described an interesting new
genus, Caelacantha anchorata; and another new form, which he placed in the
Aulosphaerida, as Aulosphcera gracilis, but which really was a new genus of Sagos-
phserida, here described as Sagoscena gracilis. Finally, Hertwig first discovered that
the peculiar bodies, described by Ehrenberg as Dictyocha and placed by him in the
Diatomea (Polygastrica), were the isolated pieces of the skeleton of a true Pheeodarium,
and that they were scattered loosely in great numbers over the surface of the jelly -sphere,
just as are the hollow spicula of Thalassoplancta or Cannobelos.

The six species mentioned, of which Hertwig gave a very accurate description and
very instructive figures, belong to six different genera, and these represent six different
families of PH/EODARIA, viz. ; Aulacanthida, Aulosphserida, Ccelodendrida, Cannosphserida,
Sagosphserida and Cannorrhaphida. He found that all these six forms, in spite of great
differences in the form and structure of their skeleton, were identical in the structure
of the central capsule ; and since he observed constantly three openings in its double
wall (a large main-opening on the oral pole, and a pair of lateral accessory openings on the
aboral pole of its main axis) he called them TRIPYLEA (loc. cit., p. 87, 94). But he also
pointed out the remarkable shape of their voluminous extracapsular body, and especially
the characteristic position, size, colour and composition of the large pigment body, which
I had called the phseodium.

The accurate description of the gigantic and elegant skeleton of a new Pheeodarium,
surpassing all other known Radiolaria in its extraordinary size (15 mm.), was published in
1882 by 0. Biitschli (in Zeitschr. f. wiss. Zool., vol. xxxvi. p. 486, Taf. xxxi.). He called
, it Ccelothamnus davidoffii, in honour of its discoverer, who had found it floating on the
surface of the Gulf of Villafranca, near Nice. He placed it among the Ccelodendrida ; it
belongs, however, to that part of this group which possesses a nasal tube, and which I
afterwards separated under the name Coelographida,

1524 THE VOYAGE OF H.M.S. CHALLENGER.

The total number of PH^EODARIA, hitherto described and illustrated by figures,
amounts therefore to seventeen species, viz., the seven species first described by myself (in
1862) ; the six new species figured by Dr. John Murray (in 1876) ; the three new species
discovered by Hertwig (in 1879) and the single species last-mentioned described by
Biitschli (in 1882). The rich collection of the Challenger has added to this small number
such an astonishing wealth of new and remarkable forms, that I can describe in the
following system of PHJEODARIA not less than eighty-four genera and four hundred and
sixty-five species. These belong to fifteen different families and four different orders.
But this great number is probably only a small part of the numerous interesting
PH^EODARIA, which are abundantly distributed over all the oceans ; those (e.g.) of the
Indian and of the Arctic Oceans are almost unknown.

The great majority of these wonderful PH^EODARIA are inhabitants of the deep-sea,
mainly of the southern hemisphere, and are so common in many stations explored by the
Challenger, that its collection contains many thousands (or rather hundreds of thousands)
of well-preserved specimens. A smaller part of the legion is found on the surface, widely
distributed over all oceans; some of these are very common (as, e.g., Aulacantha,
Aidosphcera, Sagosphcera, Ccelodendrum, Castanella, &c.) and it is difficult to explain
how they could entirely escape the eyes of all former observers.

The three general characters which distinguish the PH^EODAEIA easily and constantly
from all the other Radiolaria are the following: — (l) the double membrane, a thick
outer and a thin inner envelope, of the big central capsule ; (2) its typical main-
opening or astropyle, placed on the oral pole of the main axis, and distinguished
by a peculiar radiate operculum, with tubular proboscis ; (3) the phseodium, or the
peculiar voluminous pigment-body, which constantly lies in the oral half of the calymma,
surrounds the oral part of the central capsule, and is composed of numerous phseodella,
or singular pigment-granules of green, olive, brown or black colour.

Besides these three general and never failing marks of the PH^EODARIA, the majority
of this legion (but by no means all) possess the three following peculiarities; (1) two
parapylse or accessory openings of the central capsule, placed laterally (at the right and
left) on the aboral pole of the main axis (wanting in the Challengerida, Medusettida,
Castanellida, and perhaps in some other families) ; (2) a characteristic skeleton which is
always extracapsular, wanting only in the Phaeodinida, incomplete in the Cannorrhaphida
and Aulacanthida, but perfectly developed and of very various shapes in the twelve other
families ; usually this silicated skeleton is composed of hollow tubules, which are filled up
by jelly (PANSOLENIA) ; but in some families it is composed of ordinary solid network,
not different from that of the other Radiolaria, eg., especially in the Castanellida and
Sagosphserida ; (3) an extraordinary size of the body, as well of the central capsule
and its nucleus, as of the extracapsular skeleton ; the majority of PH^EODARIA have a
diameter of 1 to 2 mm., and are therefore from ten to twenty times as large as the

REPORT ON THE RADIOLARIA. 1525

majority of the other Radiolaria ; in some gigantic forms the diameter of the unicellular
body reaches 20 or even 30 mm.

The Central Capsule of the PH.EODARIA is the most important part of their body and
preserves in all families of this legion the same essential structure, and nearly the same
form, in striking contrast to the extraordinary variety and complication of the skeleton.
As already mentioned, it differs from the central capsule of all the other Radiolaria
in two most important peculiarities ; firstly, the double membrane of the spheroidal
capsule, and secondly, the singular structure of its constant main-opening, the astropyle.
A third constant character is the considerable size of the enclosed nucleus, the diameter
of which usually equals about half of that of the capsule itself.

The diameter of the capsule is, in the majority of PH^ODAKIA, O'l to 0'2 mm., often
also 0'3 to 0'4, rarely more than 0'5, or less than 0'05 mm.

The position of the central capsule is somewhat different in the four orders into
which we have divided the PH^ODARIA. It lies in the centre of the spherical, concentric
calymma in all the Phseocystina, or in those PH^EODARIA which possess no complete
lattice-shell — Phseodinida, Cannorrhaphida, and Aulacanthida (Pis. 101-105). The
Phseosphseria (comprising the Orosphserida, Sagosphserida, Aulosphserida, and
Cannosphserida, Pis. 106-112) all possess a very big, usually spherical lattice-shell,
and here the central capsule is much smaller than the latter and lies in its centre.
Another position is constantly occupied by the central capsule in all Phaeogromia
(Pis. 99, 100, 113-120; the families Challengerida, Medusettida, Castanellida,
Circoporicla, Tuscarorida), which have a peculiar mouth on the lattice-shell, placed on
the oral pole of its main axis ; the central capsule lies in the opposite aboral half of the
shell cavity. The Phseoconchia finally (Pis. 121-128, the families Concharida,
Ccelodendrida, and Coelographida) all possess a bivalved shell, and the capsule is here
enclosed between the two valves of the shell.

The form of the central capsule is constantly spheroidal, slightly depressed, in the
direction of the main axis, and therefore comparable to the spheroidal form of our globe.
The depression is generally very slight, so that the proportion of the minor vertical
main axis to the major horizontal or equatorial axis is about 4:5 or 5:6, often even
8 : 9 or less ; but sometimes the proportion becomes 3 : 4, or even 2 : 3, so that the capsule
becomes nearly lenticular ; very rarely its form becomes almost perfectly spherical
(PI. 101, fig. 1). The main axis stands always vertically, and is distinctly marked by
the peculiar shape of the astropyle, placed on its oral pole. Usually this pole, in the
living and freely floating PH^ODARIA seems to be the lower pole, directed downwards
(as also in the NASSELLARIA) ; but in some families it seems to be inversely directed
upwards, as in the Challengerida and Tuscarorida (Pis. 99, 100).

The two membranes of the central capsule possess in all PH^EODARIA a very different
shape, and were in all preparations which I could accurately examine (some hundreds

1526 THE VOYAGE OF H.M.S. CHALLENGER.

belonging to all families) separated by a clear, rather wide interval, filled up either by a
colourless fluid or by a structureless jelly (PI. 103, fig. 1 ; PL 123, figs. 8, 9, &c.). They
are in direct connection only at the openings. In the living PH^ODARIA, however, their
distance is very small, or they are in immediate contact without any interval (PL 101,
fig. 10 ; PL 102, fig. 1). According to the observations of Hertwig, the two membranes
are always in close contact, and without interspace, in the living PH^EODARIA ; and the
space between them is an artificial product due to the influence of the preserving fluid or of
certain chemical agents. In every case it is very easy to separate both membranes
completely, except at the openings, where they are in direct connection. We distinguish
both membranes shortly as ectocapsa and endocapsa.

The ectocapsa, or the outer membrane of the central capsule, is rather firm and
durable, double-contoured, elastic and difficult to destroy. Its physical and chemical
qualities seem to approach those of chitin. It becomes, however, stained red by carmine,
and yellow by nitric acid. Usually it appears structureless and refracts the light strongly.
In a few cases, however, it exhibits, when examined by strong lenses, a fine puncta-
tion ; and in some Aulacanthida (especially in some big forms of Aulographis and
Aulospathis) the entire ectocapsa was densely covered with peculiar curved, or S-shaped
dark corpuscles (PL 114, fig. 13). They were all of the same length, about O'Ol, and
seemed to lie on its inner face.

The endocapsa, or the inner membrane of the central capsule, is much thinner than
the outer, with which it is in immediate connection only at the openings. It
encloses the entire contents of the capsule, and becomes very distinct, as soon as the
latter are dissolved by chemical agents, or stained by carmine. In the majority of well-
preserved preparations it is irregularly plicated, and resembles a thin, but firm, crumpled
paper. Isolated pieces of the endocapsa are completely structureless, but exhibit also
a considerable resistance, in spite of their minute thickness.

Th.e openings of the central capsule exhibit in the PH^EODARIA a greater variety
than their discoverer, R. Hertwig, supposed. The majority of the legion, certainly,
possess the three openings described by him, and are therefore true TRIPYLEA. Some
families, however, have only one opening, the astropyle, which is generally present
(Challengerida, Medusettida, Castanellida, and Phaeocolla among the Phseodinida,
PL 101, fig. 1). In some other families there is a variable number of accessory
openings or parapylse, one, three, or more, e.g., especially in the Circoporida and
Tuscarorida. The former may be called Astropylea, the latter Sporopylea. Thus
only a single opening to the central capsule is constant in all PH^EODARIA without
exception, and that is the astropyle, or the large main-opening with its peculiar
structure.

The astropyle, or the single constant main-opening of the central capsule, is
distinguished by a very remarkable structure, and is sufficient of itself to separate the

REPORT ON THE RADIOLARIA. 1527

PH/EODARIA from all the other Radiolaria, and from the other Rhizopoda in general.
It is always placed on the oral pole of the main axis, forming here a peculiar cap-
shaped or flatly conical elevation, the centre of which is prolonged into a short,
cylindrical tubule ; we call the latter shortly a proboscis, and the former an operculum.
To understand better the different forms which these important parts assume in
the different families, compare PL 101, figs. 1-6 ; PL 102, fig. 1 ; PL 103, fig. 1 ;
PL 104, figs. 1-3; PL 111, fig. 2; PL 123, figs. 1-9; PL 127, figs. 4-6;
PL 128, fig. 2, &c. Compare also the first very accurate figures which R. Hertwig
has given in 1879 (loc. cit.) in his Taf. x.

The operculum of the astropyle, the most important part of this main opening
(" der Oeffnungshof der Hauptb'ffnung," in the description of Hertwig), is a circular
convex plate, always more strongly vaulted than the surrounding part of the capsule
membrane, and is sharply separated from it by a circular, often thickened and double-
contoured margin. The operculum covers the main-opening like the lid of a tea-
kettle, and the proboscis arising from its centre is comparable to the handle of that
lid. The diameter of the circular operculum is usually about half as long (rarely as
long) as the radius of the central capsule, therefore in the majority of PH^EODAEIA
0'03 to 0'06, sometimes O'l and more. Its form is sometimes more conical, sometimes
more like a mamma. Its height is usually about equal to half its diameter. It always
exhibits a very distinct radial striation, produced by numerous prominent radial ribs,
which arise in the centre and end at the circular sharply truncated margin. The usual
number of these radial ribs may be, in the operculum of smaller capsules, from thirty to
fifty, in those of medium size from sixty to ninety, and in the largest two hundred to three
hundred or more. Usually the ribs are simple (PL 101, figs. 1, 2, 6, 10 ; PL 127,
figs. 4-6 ; also in all figures given by Hertwig) ; but sometimes, mainly in the biggest
Aulacanthida, they are distinctly branched in a centrifugal direction (PL 114, fig. 13 ;
PL 115, fig. 3). Hertwig is of the opinion that the radial ribs are thickened
ridges of the endocapsa ("leistenartige Verdickungen der inneren Membran"),
and that the ectocapsa covering it is structureless (compare his figs. 1 and la, in
Taf. x.). But I am convinced now, by numerous experiments and observations, that
the radiate operculum is a part of the outer, not of the inner membrane. That part
of the latter which lies immediately beyond the former, and which may be called the
" inner operculum," also exhibits usually a fine radial striation ; but this is probably
only the cast of the stronger and much more prominent radial ribbing of the " outer
operculum " belonging to the ectocapsa. The latter exhibits a large circular opening
with thickened margin, when the radiate operculum is taken from it. The operculum
becomes stained intensely red by carmine, yellow by nitric acid, corresponding to the
ectocapsa, the main-opening of which is closed by it.

The proboscis, or the cylindrical tubule, which arises in the centre of the

1528 THE VOYAGE OF H.M.S. CHALLENGES.

operculum, is often rather short, and bears the same relation to it as the nipple
does to the human breast (PI. 104, fig. 2). But usually it is more or less prolonged
and often about as long as the radius of the capsule, rarely nearly as long as its
diameter (PI. 101, fig. 1). Its form is usually a slender cylinder, sometimes somewhat
conical and tapering towards the distal end. It is more or less curved or S-shaped in
the majority of preparations (PL 115, fig. 3; PI. 127, fig. 6, &c.). Its thin wall is
a direct prolongation of the outer membrane of the capsule, therefore it appears as a
direct apophysis of the operculum, when this is detached from the latter. The opening
at the distal end of the proboscis, through which the endosarc is thrown out, is circular.
The parapylse, or the accessory openings of the central capsule, exhibit in all
PH^ODARIA the same form and structure, but vary in number and disposition. They
are recognised with difficulty in the smaller species, since they are always of small size,
and may be easily overlooked. They seem to be completely wanting in the following
families :— Challengerida (PL 99), Medusettida (Pis. 118-120), Castanellida (PI. 113),
and in single genera of other families, as in Phceocolla (PL 101, fig. 1). The
majority of PH^EODARIA seem to possess the two lateral parapylas, first described by
Hertwig, placed at a variable distance on each side of the aboral pole, to the right and
left (PL 101, figs. 2, 6, 10; PL 103, fig. la; PL 104, figs. 1, 2a ; PL 123,
figs. 1, 8a, &c.). The horizontal axis, in which the two parapylse lie, is the frontal
or lateral axis ; and the plane, which passes through the three openings of these
" Tripylea," is the frontal or lateral plane. The number of the parapylse seems to be
variable in the two families, Circoporida and Tuscarorida, which also differ from the
other PH^ODAEIA in the peculiar (porcellanous) structure of their shell-wall. The
number seems to vary even in the single species of one genus ; and the following cases
may be found: (A) a single parapyle, placed on the aboral pole of the main axis and
directly opposed to the astropyle (on the oral pole), as in Tuscaridium (PL 100,
fig. 8); (B) three equidistant parapylse, one of which is placed in the sagittal plane,
and the two others one on each side of it, to the right and left, as in Tuscarora
(PL 100, figs. 1-6) ; the three parapylse seem to correspond here to the three long
feet, or the tubular aboral apophyses of the shell, which are arranged in a similar
manner to the three cortinar feet of the NASSELLARIA ; (C) four equidistant parapylse,
placed in pairs on the poles of the diagonal axes of a horizontal plane, as in Tuscarusa
(PL 100, fig. 7); they seem here to correspond to the four crossed aboral feet;
(D) six to eight or more parapylse, probably in the different genera of Circoporida
(Pis. 114-117); perhaps each radial tube, which is surrounded on its base by a
circle of pores, here corresponds to a separate parapyle. The number of well-preserved
central capsules belonging to the two latter families, however, which I could examine
was relatively small, and their examination very difficult ; therefore these numbers are
not stated with satisfactory certainty and require a further more accurate examination.

REPORT ON THE RADIOLARIA. 1529

The minute structure of the parapyke (or " Neben-Oeffnungen ") has been described
already very accurately by Hertwig (loc. cit., p. 95, Taf. x. figs. 1-116). The two
membranes of the capsule are in direct and immediate connection on each parapyle.
The strong outer membrane arises in the form of a ring or of a short cylindrical tubule
(collare paraboscidis or " Oeffnungshals "), is then reflected inwards, and connected at
the bottom of the cylindrical cavity with the delicate inner membrane. From this
connective ring arises a short conical or cylindrical tubule, which we call shortly the
"paraboscis." According to Hertwig (who calls it " Oeffnungskegel ") the paraboscis is
a direct prolongation of the inner membrane only. My own observations have led
me to the opinion, that the paraboscis of each parapyle is a direct prolongation of the
outer membrane (similarly to the larger proboscis of the astropyle), and that the basal
connective ring is, therefore, the inner opening of the paraboscis, through which the
entosarc enters, being protruded through its outer circular opening. Usually the
paraboscis of each parapyle is only a short cylinder, arising by a conical base ; but
sometimes, especially in some Aulosphaerida and Sagosphserida, it is prolonged into a
slender tubule, nearly as long as the radius of the central capsule. It has been already
figured by Hertwig (loc. cit., Taf. x. figs. 6-8). It seems, therefore, that the
paraboscis of the accessory openings is developed in a way similar to the proboscis of
the main-opening, and that the chief difference between the two is indicated by the
large radiate operculum of the latter.

The cavity of the endocapsa, or the spheroidal space enclosed by the inner
membrane of the central capsule, is filled up in its central part by the big nucleus, in
its peripheral part by the endoplasm,' or by the internal protoplasm, which is in com-
munication with the outer or extracapsular protoplasm by the openings of that capsule.
The endoplasm, or the intracapsular sarcode, is rather opaque, finely granulated, and
usually filled up by numerous small clear spherules of equal size, which are more or
less regularly arranged and equidistant. These spherules have usually a diameter of
O'Ol to 0'015, rarely more than 0'02 or less than 0'005 mm. ; their size is generally
equal in each capsule. They have been already described and figured in my Monograph,
as " wasserhelle kugelige Blaschen," and are probably vacuoles or small vesicles filled up
by jelly or by a clear fluid. Usually each vesicle contains a small dark granule of fat,
or a group of such granules connected together ; and in these Hertwig observed a
vibrating molecular motion. The central capsule of many PH^EODARIA contains, besides
the vacuoles, often granules of pigment (usually red or yellow) and sometimes numerous
groups of small crystals, placed mainly beyond the operculum of the astropyle (PL 127,
figs. 4—7). The outer layer of the endoplasm, placed immediately beyond the
endocapsa, often exhibits a fine striation, as if composed of delicate fibrillse. This
fibrillar striation is usually most distinct on the base of the openings, where also the
endoplasm becomes stained very intensely by carmine. The astropyle as well as

("ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 192

1530 THE VOYAGE OF H.M.S. CHALLENGER.

the parapylse often exhibit here, when observed from the face, a distinct radial striation
(compare Hertwig, loc. cit., p. 98, Taf. x. figs. 6—14). Perhaps the radiate shape of
the operculum is only produced by radial folds of the endocapsa placed beyond it, and
these folds may be in turn the product of the radial fibrillse, which are prominent
beyond the astropyle. On the other hand, these fibrillse may be compared to the
muscular fibrillse or " myophane filaments " in the ectosarc of the Infusoria, and may
perhaps effect by their contraction a dilatation of the openings of the capsule.

The nucleus of the PH^EODARIA is always very large, usually about half or two-thirds
as broad as the central capsule, and placed either in its centre, or sometimes nearer to
one pole of the main axis, which is common to the capsule and its nucleus. Therefore
the diameter of the latter is usually half or even two-thirds of that of the capsule, and
may be in the majority 0'05 to 0'15, often 0'2 to 0*3, rarely more than 0'4 or less than
O'Ol mm. The form of the nucleus is rarely spherical, usually spheroidal, and it is
more depressed in the direction of the main axis than the capsule itself. In my
Monograph, where I gave the first description of it, I called it " Binnenblaschen." The
membrane of the vesicular nucleus is thin but rather firm, and contains a rather clear,
finely granulated substance, in which numerous nucleoli are usually scattered. (Compare
PI. 101, figs. 1-10 ; PI. 102-104 ; PI. 123 ; PL 127, &c. ; the nucleus is marked by
n, the nucleoli by I.)

The nucleoli are very different in respect to their form, size, number and arrange-
ment. Since these differences are very great even in different specimens of a single
species (as, e.g., in the common cosmopolitan Aulacantha scolymantha, Aulosphcera
trigonopa, Ccelodendrum ramosissimum, &c.), it is probable that they represent
different stages of development and multiplication, and that the smallest fragments
of the nucleoli, or the final results of their repeated division, become the nuclei of the
flagellate spores, which are developed in the PH^EODARIA just as in the other Eadiolaria,
In the majority of nuclei examined, the number of the enclosed nucleoli proved to be
very great, fifty to eighty or more, often some hundreds, the greater their number the
smaller their size. Their form is usually irregular, roundish, or even amoeboid —
probably the result of amcebiform motions (PI. 101, fig. 1). Sometimes the nucleoli were
regularly spherical, equidistant, and connected apparently by a delicate network (PI. 101,
fig. 2). (Compare PL 102-104, 111, 123, and also Taf. x. of Hertwig, loc. cit.).

The calymma, or the extracapsular jelly-veil, is in the PH^EODARIA always well
developed and usually much larger than the enclosed central capsule. The entire
volume of the calymma may be three to six times as great as that of the capsule in
the majority of this legion ; but in the large Aulacanthida, Aulosphserida, Ccelo-
dendrida, Ccelographida, &c., the volume of the former is twenty to fifty times as great
as that of the latter, or even more. The jelly substance is rather firm and consistent,
clear, structureless, and becomes more or less intensely stained by carmine. In the

REPORT ON THE RADIOLARIA. 1531

larger forms it is often filled by numerous large alveoles, which are usually absent in
the smaller forms. These extracapsular alveoles are most strongly developed in the
calymma of the Phseocystina, or the PH/EODARIA with incomplete skeleton,
embracing the three families Phseodinida, Cannorrhaphida and Aulacanthida (Pis. 101-
104). Usually the calymma is here very voluminous and entirely filled up by large
alveoles, which are either spherical, irregularly roundish, or polyhedral by mutual
compression. These alveoles or vacuoles have no peculiar wall, but are only cavities in
the homogeneous substance of the jelly, and are filled by a clear aqueous fluid.
Between these the network of the anastomosing pseudopodia is expanded. They exhibit,
therefore, the same shape, as was first observed in Thalassicolla and in the Poly-
cyttaria (Collozoida, Sphserozoida and Collosphserida).

The relation of the calymma to the skeleton is in the PH^ODARIA of the same
importance as in the other Eadiolaria, and we may also here distinguish a primary and
a secondary calymma. The primary calymma is that on the surface of which at a
certain period of life (in the " shell-building period ") the fenestrated shell is secreted in
the majority of PH^EODARIA. The secondary calymma, however, is formed after this
period, and envelops the shell itself as well as its apophyses externally. Usually the
entire skeleton seems to be enveloped by the secondary calymma.

The parts of the extracapsular body, which are enclosed in the gelatinous calymma,
possess a peculiar importance in the PH^EODARIA ; these are firstly the sarcomatrix and
the pseudopodia arising from it, and secondly the phseodium. The sarcomatrix, or
the layer of extracapsular sarcode (ectoplasm), which immediately surrounds the central
capsule, is very thick and more strongly developed in all PHJEODARIA than in all other
Radiolaria. Its extraordinary size has been already mentioned by Hertwig (1879, loc.
cit., p. 99). It is in direct connection with the intracapsular sarcode (or the endoplasm)
only by the openings of the central capsule, and mainly by the astropyle. Very
numerous radial pseudopodia arise everywhere from the sarcomatrix and run to the
surface of the calymma, usually forming a rich network in it by means of numerous
branches and anastomoses (compare PI. 101-104). On the surface of the calymma
the meshes of this network are very numerous, and there arise from its nodal points
the terminal pseudopodia, which float freely in the surrounding water. The metamor-
phoses of this network of sarcode, the perpetual changes in the number and size of its
meshes, and the movements of the sarcode streams as well as of the small granules
running in it, are always very manifest in the PHJEODARIA and in the big forms of
this legion (mainly in the Aulacanthida) they are better observed than in the majority
of other Radiolaria. In many PH^EODARIA (and perhaps in all) a part of the pseudo-
podia seems to have undergone a local differentiation, for special physiological pur-
poses ; and Hertwig has described a peculiar conical contractile body, which arises in
Ccelodendrum between the two parapylse (loc. cit., p. 100, fig. 3). Further examination

1532 THE VOYAGE OF H.M.S. CHALLENGER.

of these interesting organs in living PH^EODARIA is required. Usually the sarcode, issuing
from the openings of the capsule, forms a stronger cylinder, with peculiar movements.

The phseodium, or the peculiar dark extracapsular pigment-body of the PH^EODARIA,
is one of the most important and most characteristic parts of their organisation,
and has induced me to derive their name from it ; it is not less typical for the whole
legion, than the astropyle with its radiate operculum and the proboscis ; and both
these important parts are always in direct topographical and physiological connection.
Whilst I have missed the phseodium in no Ph&odarium in which the soft body
was well preserved, I have not found it in any other Radiolaria ; for the similar extra-
capsular pigment bodies, which are found in some species of Tlicdassicolla and some
other Sphserellaria, have a composition and signification different from that of
the phseodium — an exclusive peculiarity of the PH^EODARIA.

The typical importance of the phseodium for all members of this legion is proved
by the following five facts : — (l) its constant presence in all PH^EODARIA ; (2) its
constant excentric position in the oral half of the calymma ; (3) its constant relation to
the astropyle, the operculum and the proboscis of which is always surrounded by it ;
(4) its constant considerable size, its volume being usually greater than that of the
central capsule, the aboral half of which is covered by it ; (5) its constant colour and
morphological as well as chemical composition. These five facts together demonstrate
by their absolute constancy the high morphological and physiological importance of
the phseodium for this peculiar subclass of Eadiolaria, although its true nature is
difficult to make out, and its main function is not yet sufficiently known.

The first remarks that have been made on the phseodium were published in 1862
in my Monograph, where I noticed the peculiar dark brown extracapsular pigment
body and its excentric position covering only one-half of the central capsule, in Aula-
cantha (p. 263, Taf. ii. figs. 1, 2), in Thalassoplancta (p. 262, Taf. iii. fig. 10), and in
Caslodendrum (p. 361, Taf. xxxii. fig. 1). Its general presence and peculiar composition
were first recognised by Dr. John Murray, who had, during the Challenger Expedition,
the first opportunity of examining many big living PH^EODARIA brought up from great
depths. He gives in his first Report (1876, loc. tit., p. 536), the following important
notice : — " The sarcode of all these deep-sea Rhizopods has many large black-brown
pigment-cells. Small bioplasts are scattered through the sarcode. These collect into
capsular-like clumps when the animal is at rest, and are quickly coloured by carmine."
In 1877 Dr. John Murray sent me the wonderful collection of PH^ODAEIA brought
home by the Challenger, and I had now the best opportunity for examining the
phseodium in hundreds of well-preserved specimens. Supported by these extensive
observations, I gave, in 1879, in a preliminary paper,1 a fuller description of the

1 Ueber die Pha;odarien, eine neue Gruppe kieselschaliger mariner Rhizopoden, Sitzungsb. med.-nat. Gesellsch. Jena,
December 12, 1879, pp. 3, 4.

REPORT ON THE RADIOLARIA. 1533

phseodium, and of the phseodella (or the peculiar dark pigment-granules composing
it). At the same time R. Hertwig published his observations on the big living TBJPYLEA
examined by him at Messina, and pointed out particularly that the constant presence,
composition, and arrangement of this excentric extracapsular pigment-body was most
characteristic, and sufficient in itself to distinguish this group from all the other Radio-
laria (1879, loc. cit., p. 99).

The most striking peculiarity of the phseodium, and the most important on
account of its absolute constancy, is its excentric position, covering only the oral hemi-
sphere of the central capsule, and wholly or partly wanting on the aboral hemisphere.
This constant topographical relation to the capsule never fails, and may be always
observed at the first glance, when the body is seen from the side (the main axis of
the capsule being perpendicular to the axis of the eye of the observer), (compare
PI. 101, figs. 6, 10 ; PL 102, fig. 1 ; PL 103, fig. 1, &c.). The phseodium envelops,
therefore, the oral half of the capsule completely, and especially the astropyle in its
centre ; hence, the radiate operculum and the proboscis arising from the latter cannot
be seen usually before the former is removed. The general form of the entire
phseodium, in consequence of this excentric position, is concavo-convex (or crescentic
in longitudinal section), its concave face embracing the oral or anterior face of the
capsule, and its convex face being turned to the surface of the calymma.

The topographical relation of the phseodium to the surrounding shell is also
very characteristic in the suborder Phseogromia, or in those PH^EODARIA which
possess a peculiar shell-mouth placed on the oral pole of its main axis. Here
the capsule is always placed in the aboral half of the shell-cavity, the phseodium in
its oral half, separating the astropyle from the mouth of the shell, both of which
lie in the main axis ; as in the Challengerida (PL 99), Tuscarorida (PL 10O),
Castanellida (PL 113), Circoporida (PL 115), and Medusettida (PL 118-120).
In this suborder (the Phseogromia), the volume of the phseodium may be, on an
average, about as great as that of the central capsule, whilst in the majority
of other PH^EODARIA it is much greater than the latter.

A similar topographical relation between the phseodium and the enclosing shell, as
in the Phseogromia, also exists in the suborder Phseoconchia, or in those
PH^ODARIA, which are distinguished from all the others by the possession of a bivalved
shell (PL 121-128). The two valves of this curious shell, which resembles that of the
Brachiopoda, are dorsal and ventral, and the tripylean central capsule is always so
placed between them that its two lateral parapylse (right and left) lie in the frontal
plane of the shell, where a large frontal fissure opens between the opposed margins of
the two hemispherical or cap-shaped valves. The phseodium is also placed here on
the oral half of the capsule and surrounds its astropyle ; but it exhibits some differences
in the three families ofPhseoconchia.

1534 THE VOYAGE OF H.M.S. CHALLENGER.

The Concharida, the bivalved shell of which is simple, and without tubular apophyses
(PI. 123-125), possess a relatively small central capsule, which usually fills up only
the third or fourth part of the shell-cavity. This is the aboral or posterior part, on
the apex of which both valves are united by a ligament in some Concharida (PI. 1 23,
figs. 8, 9). The oral or anterior part of the shell-cavity (usually two-thirds or more) is
filled up by the phseodium, and this is usually bifid, being divided by a frontal
constriction into two wings or lobes ; the dorsal wing is hidden in the upper valve of
the shell, the ventral wing in the lower valve ; both wings are usually united only by
a small central bridge, and this bridge of the phseodium is pierced in its centre by the
proboscis of the astropyle (PL 124, figs. 6, 10 ; PI. 123, figs. 8, 9).

The Coelodendrida have a different shape (PI. 121). Their bivalved shell is rela-
tively small and tiny, and bears on the two poles of the sagittal axis two conical
apophyses or galese, from each of which three or four very large, dichotomously
branched tubes arise. The central capsule fills up the cavity of the bivalved shell
almost entirely, and the voluminous dark phseodium envelops both to such an extent
that the shell and the enclosed capsule are often hidden in it completely. Therefore
I arrived in my first description of Ccelodendrum (1862, loc. cit.) at the erroneous
conclusion that the capsule lies outside, not inside the shell. The first accurate
figure and description of its structure was given in 1879, by Hertwig (loc. cit., p. 99,
Taf. x. fig. 3). The central capsule (v) is here separated from the bivalved shell
(m) only by a very small distance, and the oral part of both is hidden in the
phseodium. I find, however, in the majority of the numerous preparations of the
Challenger collection, the volume of the phseodium much greater, and it often envelops
the entire shell.

The Cffilographida, finally, have a phseodium of the most remarkable shape, since
in their bivalved shell a peculiar reserve store or magazine of phseodella, which we
call the "phseocapsa" is developed for it (PI. 126-128, g.t.m.}. The bivalved shell
has in these most perfect PH^ODABJA a structure similar to that in the Crelodendrida ;
but they differ from the latter in the stronger development, and greater differentiation
of the two apical galese, and the large hollow tubes arising from them. These two
helmet-shaped cupolse, the galese (#), which arise from the two valves on the poles of
the sagittal axis, are in the Coelographida usually larger than the valves themselves,
and are not closed, as in the Coelodendrida, but open by a tubular apophysis at their
base, the nasal tube or rhinocanna (t). The apex of the galea is connected with the
open mouth of the rhinocanna by a single or double frenulum (b). The two nasal
tubes or rhinocannse (a dorsal and a ventral) lie in the sagittal plan£ of the body (and
run from the base of each galea along the anterior convexity of the valve to its oral
margin. Here is placed the proboscis of the astropyle, between the two opposed
mouths of the rhinocannse (PI. 128, fig. 2). The phseodium is usually hidden entirely

REPORT ON THE RADIOLARIA. 1535

in the two phseocapsse, which are composed of the two galeae (g), and the two
rhinocannse arising from them (PI. 127, figs. 4—9). A part of the phseodella is
usually thrown out by the mouth of the latter (?»,).

The characteristic colour of the phseodium exhibits numerous different tints between
green, brown, and black. It seems to be in the majority blackish-brown or greenish-
brown, very often olive, more rarely almost quite green or red-brown. Usually the
colour is so dark, intense and opaque, that the parts enclosed by the phseodium,
mainly the oral hemisphere of the central capsule and the astropyle, are completely
hidden in it. The chemical composition of the phasodium demands further accurate
researches ; unfortunately I have not been able to make out its true nature, since
numerous different experiments furnished no certain general results.

The phaeodella, or the pigment -corpuscles, which compose the phseodium, aggre-
gated in hundreds, and in the bigger species in thousands, are usually spherical, some-
times somewhat ellipsoidal, at other times spheroidal or lenticular ; but usually
numerous smaller, irregular, roundish particles are intermingled between the larger and
more regular corpuscles, and often the main mass forms a very fine black powder.
The size of the phseodella is very variable, not only in the different species, but also in
one and the same individual. The larger pha3odella have a diameter of O'Ol to 0'02,
the smaller of 0'004 to O'OOS mm. ; but there also occur very big forms of 0'04 to 0'05
mm., or even more, and very small ones of O'OOl mm. or less. Usually the phaeodium
appears as an aggregate of numerous larger and smaller phaBodella, which are very
different in size as well as in the intensity and tint of their colour, and are irregularly
crowded in a black, powder-like substance.

The morphological nature of the phaaodella is also difficult to make out. I have
already pointed out in my first description of Aulacantha, Thalassoplancta and
Ccelodendrum (1862, loc. cit.), that a great part of these pigment-corpuscles are true
cells, composed of a nucleus and protoplasm, which contains granules of pigment,
and is enveloped by a membrane. Dr. John Murray, who had during the Challenger
voyage the opportunity of examining numerous different living PH^EODARIA, and staining
them by carmine, also asserts that a great part of those dark corpuscles are " large
black-brown pigment-cells" (1876, loc. cit., p. 536). Numerous preparations of the
Challenger collection, well preserved in glycerine, and stained by carmine, contain
PH^ODARIA belonging to different families, the phaeodium of which contains numerous
such " pigment-cells," with a dark red nucleus, and so similar are these cells, that every
histologist should recognise them. But in strange contrast to this is the fact, that in
numerous other mountings, prepared in the same manner, not a single cell of this
kind is found in the phseodium, and that the latter is composed only of irregular
pigment-granules. In many PH^EODARIA belonging to different families I, like Hertwig,
could not find a single true nucleated cell in the phseodium.

1536 THE VOYAGE OF H.M.S. CHALLENGER.

A great part of the PH^ODARIA, and usually the bigger forms of Aulacanthida, Cannor-
rhaphida, Coelodendrida, Coelographida, &c., exhibit a peculiar structure of the larger
phseodella, viz., a fine parallel striation (PL 101, figs. 3, 6 ; PI. 102, fig. 1 ;
PI. 103, fig. 1 ; PI. 104, figs. 1—3, &c.). In each phseodellum may be counted
about ten to twenty such fine parallel stripes (more in the greater, less in the
smaller forms) ; and in the ellipsoidal phasodella the stripes are either transverse
rings, perpendicular to their main axis, or ascending obliquely ; they often resemble
the convoluted spiral filament of a thread-cell or nettle-cell of an Acaleph. Some-
times these parallel transverse stripes are very striking. Another structure is seen
in larger phseodella, namely an aggregate or cluster of smaller globules, often of equal
size, resembling a small morula. All these minute structures of the phseodella as
well as their changes in the living PH^EODARIA, require a far more extensive examina-
tion (by means of strong lenses and different chemical reagents), than I could,
unfortunately, devote to them.

The physiological signification of the phseodella, therefore, is at present not yet
known ; but the general facts quoted above, their constant presence, position, volume,
and composition, make it probable that their physiological value in the PH^ODARIAN
organism is very great. The following hypotheses may be taken provisionally into
consideration : — A. The phseodella are peculiar symbiontes, or unicellular algse, compar-
able to the xanthellse or zooxanthellse of the other Radiolaria. This hypothesis is pro-
bably correct for those phseodella which are true nucleated cells ; and the more so, as the
majority of PH^EODARIA do not exhibit those common yellow xanthellse, which are
usually found in the SPUMELLARIA and NASSELLARIA. It is even possible that the latter
are absent in all PHJEODARIA. B. The phseodella are dark pigment-bodies, which absorb
light and heat in a manner similar to the simple " pigment-eyes" of many lower animals,
and may therefore be optical sense-organs of the PHJEODARIA. This hypothesis may be
supported by a comparison with the large -eyed unicellular Protist, Erythropsis agilis,
described by R. Hertwig. C. The phseodella are organs of nutrition of the PH^ODARIA
and active in their metastasis (" Stoffwechsel "). Regarding them from this point of
view, we may suppose that the phseodella are secreted products which serve for digestion,
acting like the bile or the saliva of higher animals. Perhaps they too act like the
venomous matter produced in the thread-capsules of the Acalephse. The suggestion
that they are mere excretions, or half-digested matters, as Hertwig supposes (" halb
assimilirte Nahrungs-bestandtheile," 1879, loc. cit., p. 99) seems less probable. The
most important fact illustrating their high signification for the processes of nutrition,
digestion and for effecting changes on matter, seems to be the close relation of the
phseodium to the astropyle ; the radiate operculum of the latter, and the proboscis
arising from it, being constantly covered and completely hidden by the central main
mass of the phseodium.

REPORT ON THE RADIOLARIA. 1537

The skeleton of the PHJEODARIA is always extracapsular, and exhibits in the majority
of this legion such a characteristic shape, form, and structure, that these organisms
may be easily recognised by it, even apart from the central capsule and the phseodium.
In a few cases, however, the skeleton is so similar to that of some NASSELLARIA and
SPUMELLARIA, that it may be accidentally confounded with it. In general the skeleton
of the PH^EODARIA is much larger, and much more highly developed, than that of most
other Radiolaria, and exhibits the most wonderful appearances, and the most
marvellous complications, which are found in the whole world of Protists, or of unicellular
organisms. The varied composition and differentiation of the skeleton alone distinguishes
the numerous families, genera, and species of PH^EODARIA described in the sequel ;
all the fifteen families, however, agree so completely in the structure of the central
capsule and the phseodium described, that we may derive them all phylogenetically
from a small skeletonless family, the Phseodinida.

The chemical composition of the skeleton seems to be, in the majority of PH^EODARIA,
somewhat different from that of the other Radiolaria. In a few groups only, especially
in the Cannobelida ( Piety ocha, Mesocena, &c.), and in a part of the Castanellida and 7
Concharida, the substance of the skeleton seems to be of pure silica, as in the NASSELLARIA vjuMy^ ^

and SPUMELLARIA ; these flinty skeletons, therefore, may be also found fossil. In the 1

majority of PH^EODARIA, however, the skeleton does not consist of pure silica, but of
an organic silicate ; it becomes more or less intensely stained by carmine, and
browned or blacked by fire ; in many cases it even becomes completely burned and
destroyed by the prolonged action of heat. This circumstance explains why PH^EODARIA
in general are rare in deep-sea deposits, as in the common Radiolarian ooze of the
Pacific, and why they are generally absent in fossil deposits. Even the pure Radiolarian
rocks of the Barbados, &c., contain only a few PH^EODARIA, mainly Dictyochida.

According to the different forms of the skeleton, we may divide the legion or sub-
class of PH^EODARIA into two sublegions, four orders, and fifteen families. Firstly, we
may distinguish as two groups the Phseocystina, without a lattice-shell, and the
Pheeocoscina, with a lattice-shell (compare above, p. 5). The Phseocystina
comprise three different families, viz., (l) Pha3odinida, without any skeleton (PI. 101, figs.
1, 2); (2) Cannorrhaphida, with an incomplete skeleton, composed of numerous separate,
not radial pieces, which are scattered around the capsule in the calymma (PI. 101, figs.
3-14; PL 114, figs. 7-13), and (3) Aulacanthida (PI. 102-105), with an incom-
plete skeleton, composed of numerous hollow radial tubes, which pierce the calymma
and come in contact by their proximal ends with the surface of the central capsule.

The Phseocoscina, or the PH^EODARIA with a lattice-shell (embracing the great
majority of the whole legion) exhibit three principal differences in the shape of their shell,
and from these we distinguish the three following orders ; (A) Phseosphseria,
with a spherical, not bivalved shell (rarely of an ellipsoidal or lenticular, or another

(ZOOL. CHALL. EXP. - PAET XL. — 1886.) Rr 193

1538 THE VOYAGE OF H.M.S. CHALLENGER.

modified form), without a shell-mouth or a peculiar constant large opening on the
lattice-shell ; (B) Phseogromia, with an ovate or polyhedral, not bivalved shell
(often also of a subspherical, ellipsoidal, or another modified form), constantly provided
with a shell-mouth or a peculiar large opening on one pole of the main axis of the
lattice-shell ; (C) Phseoconchia, with a bivalved shell, composed of two completely
separated, hemispherical, cap-shaped or boat-shaped valves (a dorsal and a ventral),
comparable to that of the Brachiopoda.

The Phseosphaeria, or those PH^EODAKIA the big shell of which is usually spherical,
never bivalved and never provided with a peculiar shell-mouth, comprise a great number
of common and large-sized PHJSODARIA, which may be arranged into four different
families, according to the different structure of the shell — (l) Orosphserida (PL 106, 107),
spherical shell extremely big and robust, composed of a single piece of coarse lattice-
work, the thick bars of which are stratified and contain partly a fine axial-canal, meshes
of the network usually irregularly polygonal, no astral septa in the nodal points ; (2)
Sagosphserida (PI. 108), spherical shell large-sized, but extremely delicate and fragile,
composed of a single piece of arachnoidal lattice-work, the thin bars of which are simple
solid threads, without axial -canal, meshes of the network always large and triangular,
no astral septa in the nodal points ; (3) Aulosphserida (PI. 109-111), spherical shell
large-sized, but very fragile, composed of numerous hollow cylindrical tubes, which are
connected (and at the same time separated) by peculiar astral septa in the nodal points,
meshes either triangular or polygonal; (4) Cannosphasrida (PI. 112), spherical shell
double, composed of two concentric shells which are connected by thin hollow radial
tubes, the inner shell simple, solid or fenestrated, with a shell-mouth on the basal
pole, the outer shell composed of hollow cylindrical tubes which are connected by astral
septa in the nodal points. The structure of this outer shell is the same as in the
Aulospheerida, while the basal mouth of the inner shell brings this family in closer
relationship to the Phseogromia.

The Phaeogromia, or those PH^ODAEIA the shell of which is not bivalved, but
provided with a peculiar constant mouth on the oral pole of the main axis, are in
general similar to the NASSELLAKIA (Monocyrtida), and may be divided into five
different families, viz., (l) Challengerida (PI. 99), shell ovate or subspherical, also often
triangular or lenticular, distinguished by a peculiar diatomaceous structure, an exceed-
ingly fine tracery of regular hexagonal, very delicate network; (2) Medusettida
(PI. 118-120), shell ovate, campanulate or cap-shaped, distinguished by a peculiar
alveolar structure, with a corona of peculiar hollow, large, articulated feet around the
mouth; (3) Castanellida (PI. 113), shell spherical or subspherical, of ordinary simple
lattice-work, usually with a corona of simple solid teeth around the mouth ; (4)
Circoporida (PI. 114-117), shell spherical or polyhedral, with panelled or dimpled
surface, distinguished by a peculiar porcellanous structure (numerous thin needles being

EEPORT ON THE RADIOLARIA. 1539

embedded in a punctulate cement-substance), with hollow radial spines and with a corona
of simple solid teeth around the mouth ; (5) Tuscarorida (PI. 100), shell ovate or
subspherical, with smooth surface, of the same peculiar porcellanous structure as the
Circoporida, but with hollow, very long, tubular teeth around the mouth.

The Phseoconchia are the peculiar and most interesting " PH^EODARIA bivalva,"
differing from all other PH^EODARIA, and from all known Radiolaria in general, in the
possession of a bivalved lattice-shell, composed of a dorsal and a ventral valve. They
maybe divided into three families: (1) Concharida (PI. 123-125), shell with two
thick and firm, regularly latticed valves, which bear no hollow tubes and no cupola or
galea on their apex or sagittal pole; (2) Ccslodendrida (PI. 121), shell with two
thin and fragile, scarcely latticed valves, which bear a conical cupola or a helmet-shaped
galea on their apex, and hollow branched tubes arising from it (without rhinocanna and
frenula) ; (3) Ccelographida (PI. 122, 126-128), shell with two thin and fragile,
scarcely latticed valves, similar to those of the Ccelodendrida, but differing from them
in the development of a peculiar rhinocanna or nasal tube upon each valve ; this tube
is connected by an odd or paired frenulum with the apex of the galea, and both
together contain the phseodium.

The phylogenetic affinity of the fifteen families enumerated, and the morphological
relationship based upon it, form a very difficult problem. The whole legion of PH.EODARIA
is probably monophyletic, in as much as all the families may be derived from a single
ancestral group, the skeletonless Phseodinida (Phceodina and Phceocolla] ; but at the
same time polyphyletic, in as much as probably many families have been derived, indepen-
dently one from another, from different branches of Phseodinida ; or in other words,
the characteristic malacoma of the PH^EODARIA (the cannopylean central capsule and the
calymma with the phseodium) may be a monophyletic product, inherited from a single
ancestral form ; the manifold skeleton, however, is certainly a polyphyletic product,
originating from different skeletonless Phseodinida.

Among the independent families of PH^EODARIA, derived directly from skeletonless
Phseodinida by production of a peculiar skeleton, may be the following : Cannorrhaphida
(PL 101, probably polyphyletic) Aulacanthida (PI. 102-105), Castanellida (PI. 113),
Challengerida (PI. 99), Concharida (PL 123-125), Circoporida (PL 114-117) and
Tuscarorida (PL 100). The four families of Phseosphseria (the Orosphserida,
Sagosphserida, Aulosphserida and Cannosphserida (PL 106-112), may be derived
perhaps from the Castanellida; and the Medusettida (PL 118-120), have been
perhaps derived from the Challengerida. The complicated affinities of these groups are
however difficult to explain. The Coelodendrida (PL 121) are probably derived from
the Concharida, and the Ccelographida (PL 126-128) from the Coelodendrida.

The geometrical fundamental form of the shell is in the majority of PH^ODARIA
monaxonial, corresponding to the main axis of the enclosed central capsule ; the

1540 THE VOYAGE OF H.M.S. CHALLENGER.

astropyle of the latter, placed on the oral pole of the main axis, corresponds to the
mouth of the shell in all P h se o g r o m i a. In the Phseosphseria, where no
peculiar shell-mouth is developed, the general fundamental form of the shell is usually
homaxonial or spherical, often an endospherical polyhedron, rarely ellipsoidal or spindle-
shaped (with prolonged main axis), or lenticular (with shortened main axis). The
bivalved Phseoconchia have usually either an amphithect shell (with the same
fundamental form as the Ctenophora), or a dipleuric, bilaterally symmetrical shell (with
a dorsal and a ventral valve, a right and a left parapyle). A small number of
PH^EODARIA (mainly Circoporida) are remarkable on account of the regular polyhedral
form of their shell, the geometrical axes of which resemble crystalline axes and are
denned by regular radial tubes; as the octahedral Circoporus (PL 117, fig. 6),
the dodecahedral Circorrhegma (fig. 2), and the icosahedral Circogonia (fig. 1).

The siliceous or silicate bars, which compose the skeleton of the PH^EODARIA, are in

the majority hollow tubes, filled up by jelly ; in some other families, however, they

are solid rods, as in the NASSELLARIA and SPUMELLARIA. Such usual lattice-work,

composed of solid rods, occurs only in the families Sagosphserida (PI. 108), Castanel-

lida (PI. 113), and Concharida (Pis. 123-125). A quite peculiar structure, a

diatomaceous tracery of extremely fine and regular hexagonal frames, distinguishes the

Challengerida (PI. 99). The hollow cylindrical tubes, which are found in the other

families, appear in three different forms, simple, articulate, and provided with an axial

thread. Simple hollow tubes, which are neither articulate, nor provided with an axial

thread, occur in the Cannorrhaphida (PL 101) Aulacanthida (PL 102-105),

Coelodendrida (PL 121, 122), and Ccelographida (PL 126-128). In all these

families the hollow cylindrical tubes have a very thin wall and contain a wide cavity,

filled only by jelly. The Orosphserida (PL 106, 107), differ in the reduction of the

cavity, which becomes very narrow (often rudimentary or lost), whilst the walls of the

tubes become extremely thickened and stratified, numerous concentric 'layers of silica

being disposed one over the other. The hollow cylindrical tubes contain an axial

filament, or a thin thread of silica, placed in its axis, in the families Aulosphserida

(PL 109-111), Cannosphserida (PL 112), Circoporida (PL 114-117), and Tusca-

rorida (PL 100). Usually the axial filament is connected with the thin wall of

the tube by numerous horizontal branches. A quite peculiar structure distinguishes

the Medusettida (PL 1 18-120) ; their hollow tubes, extremely prolonged, are articulate

owing to the presence of numerous, regular, equidistant transverse septa ; these

are pierced by a short tubule, similar to the siphon of the shells of Nautilus ; this

remarkable alveolar structure also occurs in the peripheral part of their shell-wall

(and sometimes in the whole shell), numerous small polyhedral chambers or alveoles

which communicate by small openings, being developed ; they become easily filled

with air in the dry shell (PL 120, figs. 11-16).

REPORT ON THE RADIOLARIA.

1541

The substance of the siliceous or silicated shell-wall is, in the majority of
PH.-EODARIA, homogeneous and structureless, as in the SPUM ELL ARIA and NASSELLARIA ;
but sometimes it acquires a peculiar structure. The thickened wall of the hollow tubes in
the Orosphaerida and in several Aulacanthida (PI. 105, figs. 6—10) becomes distinctly
stratified, concentric strata being disposed one over the other. A very remarkable
structure, differing from that in all other Eadiolaria, is found in the porcellanous shell
of the Circoporida (PI. 114-117), and Tuscarorida (PI. 100). The thickened wall
of the opaque shell is here composed of a peculiar silicated cement, which encloses numerous
very thin and irregularly scattered needles (PL 115, figs. 6-9; PI. 116, fig. 3).
Dry fragments of these shells, observed by a strong lens, appear finely punctulate,
and probably air, entering into these fine porules of the cement, causes the white colour
and the calcareous or porcellanous appearance of the opaque dry shell. Its surface is
smooth in the Tuscarorida (PI. 100), panelled in the Circoporida (PI. 114-117).

The hollow or solid spines, which arise from the shell of the PILEODARIA, exhibit
an extraordinary variety and elegance in the production of different branches, bristles,
hairs, secondary spine, and thorns, hooks, anchor-threads, pencils, spathillse, &c.
These appendages are developed similarly to those of many SPUMELLARIA, but exhibit a
far greater variety and richness in form. They are organs partly for protection, partly
for retention of food. They are much more interesting than in other Radiolaria.

I. Order

PH^OCYSTINA.

Skeleton absent or in-
complete, composed of
numerous single scattered
pieces, without connec-
tion. Central capsule
placed in the. centre of
the calymma. «

II. Order

Synopsis of the Orders and Families of PHJEODARIA.

Skeleton completely absent, ....

Skeleton composed of numerous scattered pieces, not
of radial tubes, .....

Skeleton composed of numerous hollow radial tubes, the
proximal ends of which are in contact with the central
capsule, ......

Skeleton a simple or double
lattice-shell, not bi valved,
without a peculiar shell-
mouth (shell usually <
spherical, rarely of amodi-
fied form, always without
peristome). Central cap-
sule placed in the centre
of the shell-cavity.

Shell composed of a simple,
non-articulated lattice-
plate, without astral
septa in the nodal points.

Shell composed of numer-
ous hollow, tangential
cylindrical tubes, which
are separated by astral
septa in the nodal
points.

[ Network very robust and
coarse, with irregular
polygonal meshes ; bars
very thick, partly hollow,

Network very delicate and
fragile, with subregular,
triangular meshes; rods
very thin, iiliform, always
solid,

Shell articulated, with astral
septa, without a simple
central shell,

Shell double, composed of
two concentric shells ;
the outer articulated, the
inner simple,

2. CANNORRHAPHIDA.

3. AULACANTHIDA.

4. OROSPHJSRIDA.

5. SAGOSPHJ3RIDA.

6. AULOSPH^ERIDA.

7. CASNOSPH^RIDA.

1542

THE VOYAGE OF H.M.S. CHALLENGER.

Synopsis of the Orders and Families of PH^EODARIA — continued.

III. Order

PILEOGKOMIA

Skeleton a simple lattice-
shell, not bivalved, con-
stantly provided with
a peculiar large shell-
mouth placed on the
oral pole of the main
axis ; peristome usually
surrounded by peculiar
feet or teeth. (Shell
either spherical or ovate,
or of another form).
Central capsule excentrie,
placed in the aboral half
of the shell-cavity.

IV. Order

PH^EOCONCHIA.

Skeleton a bivalved lattice-
shell, composed of a dorsal
and a ventral valve which
are completely separated
(rarely connected by a
ligament on the aboral
pole). Central capsule
enclosed bet ween the two
valves.

Structure of the shell not
porcellanous (without
needles imbedded in a -

punctulate
stance).

cement^sub-

Structure of the shell por-
cellanous, with peculiar
fine needles imbedded in
a punctulate cement-
substance (a circle of
pores around the base
of each radial tube).

Structure of the shell
diatomaceous, with very
delicate and regular hexa-
gonal pores. No articu-
late feet,

Structure of the shell alveo-
lar, with hollow alveoles
between a double plate.
A corona of articulated
feet around the mouth, .

Structure of the shell of sim-
ple lattice-work, neither
diatomaceous nor alveo-
lar. No articulate feet,

Surface of the shell pan-
elled or dimpled (spheri-
cal or polyhedral). Peris-
tome flat,

Surface of the shell smooth,
even (ovate or subspheri-
cal). Peristome pro-
minent,

The two valves of the bivalved shell thick and firm,
regularly latticed, without a galea or cupola on their
apex, and without hollow tubes,

The two valves of the
bivalved shell very thin
and fragile, scarcely lat-
ticed, each with a conical
cupola or a helmet- "
shaped galea on its
sagittal pole or apex,
and with hollow tubes.

Galea without rhinocanna
or nasal tube, without
frenula, .

Galea with a rhinocanna or
nasal tube, both con-
nected by an odd or
paired frenulum,

8. CHALLBNGEKIDA.

9. MEDUSETTIDA.

10. CASTANELLIDA.

11. CIRCOPORIDA.

12. TUSCARORIDA.

13. CONCHAKIDA.

14. CCEIXJDENDRIDA.

15. CCELOGRAPHIDA.

Order I. PREOCYSTINA, Haeckel (1879).

Definition. — PH^ODARIA without lattice-shell, either without any skeleton, or with
an incomplete skeleton, composed of numerous single pieces, which are scattered in the
calymma without connection. Central capsule placed in the centre of the spherical
calymma.

REPORT ON THE RADIOLARIA. 1543

Family LXXI. PH^ODINIDA, Haeckel (PI. 101, figs. 1, 2).

Phceodinida, Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12, p. 4.

Definition. — PH^ODARIA without skeleton. Central capsule with one to three (or
more) openings, placed in the centre of the spherical naked calymma.

The family Phseodinidais the simplest and most primitive of the PHJSODARIA, and
differs from all the other families of this legion in the complete absence of a skeleton. It
bears, therefore, the same relation to the latter as the Thalassicollida do to the other
SPUMELLARIA. The soft body is only composed of the central capsule with the nucleus,
and the calymma with the phseodium.

Of course it is quite possible that the skeletonless PH^EODARIA, which we regard
here as the ancestral family of that legion, may be either members of other families
which have lost their skeleton accidentally, or young PILEODARIA which have not yet
developed a skeleton. But in some preparations of the Challenger certain large, well-
preserved PH^EODARIA, without any trace of skeleton, are not rare; and since I myself
have observed a complete living Phceodina, I have no doubt that they are independent,
primordial forms (like Actissa, Thalassicolla, Cystidium, Nassella, &c.). Probably
also two skeletonless PH^ODARIA belong to this family which are figured by R. Hertwig,
in 1879, in his Organismus d. Radiol. (Taf. x. fig. 1,11); this author, however, supposed
that they had lost their original skeleton.

The three species of Pha3odinida which are described in the sequel represent two
different genera, Phceodina and Phceocolla, already distinguished in my first note on the
PH^EODARIA (Sitzungsb. med.-nat. Gesellsch. Jena, 1879, Dec. 12, p. 4). Phceodina is a
true TRIPYLEA, and has the usual three openings which occur in the majority of PH^EO-
DARIA, a large astropyle or main-opening on the oral pole of the main axis, and a pair of
lateral accessory openings, or parapylse, on the aboral pole. Phceocolla, however, has
only a single opening, the astropyle, and agrees therefore with those PELEODARIA which
possess no parapylse (Challengerida, Medusettida, Castanellida, &c.).

The complete body is in all observed Phseodinida a small jelly sphere of 1 to 3 mm.
in diameter, with a transparent cortical layer and an opaque dark central part. This
latter is the phseodium, in which the central capsule is hidden, surrounded on all sides
by the gelatinous spherical calymma ; the smooth surface of the latter is spherical.

The central capsule of the Phseodinida (PI. 101, figs. 1, 2), is either spherical or
spheroidal, somewhat lenticular, slightly depressed in the direction of the main axis. Its
diameter is between 0 "15 and 0'25. Its double membrane exhibits the same structure
as in the other PH^IODARIA. The thick, double-contoured outer membrane is separated
from the thin and delicate inner membrane by a clear space, filled up by jelly or by a fluid ;
the two are connected in Phceocolla (fig. 1) only at the astropyle, in Phceodina (fig. 2)

1544 THE VOYAGE OF H.M.S. CHALLENGER.

they are also connected at the two parapylse. The radiate operculum of the astropyle
opens by a tubular prolongation or proboscis, which is very long in the former, shorter in
the latter. The two parapylse of the latter also bear short tubules. The protoplasm,
enclosed in the inner membrane, contains numerous small circular vacuoles. The large
central nucleus is sometimes spherical or ellipsoidal, at other times spheroidal or
lenticular ; it always contains numerous nucleoli. One specimen observed, with • two
nuclei, was apparently engaged in self-division (fig. 2).

The spherical gelatinous calymma, in the centre of which the central capsule is placed,
has a diameter of 1 to 2 mm. In the specimen of Phceodina tripylea, which I observed
living, it exhibited exactly the same shape as the figure of Dictyocha stapedia in
PI. 101, fig. 10; the only distinction in this latter being indicated by the pileated pieces
of the skeleton on the surface. The jelly-sphere contained numerous roundish or globular
alveoles of very different sizes, and between them an areolated network of protoplasm ;
the latter has arisen from the outer surface of the calymma in the form of very numerous,
radiating, partly branched and anastomosing pseudopodia. The dark and opaque centre
of the jelly-sphere is filled up by the granular, blackish-brown pheeodium, which envelops
the oral half of the central capsule completely ; it exhibits the same characters as in all
the other PHJEODAKIA.

Synopsis of the Genera of Phceodinida.

Central capsule with a single opening (an astropyle on the oral pole), . . . 656. Pliaiocolla.

Central capsule with three openings (an oral astropyle and two aboral parapylse), . 657. Pluvodina.

Genus 656. Phceocolla,1 Haeekel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena,

Dec. 12, p. 4.

Definition. — P hseodinida with a single aperture to the central capsule (an
astropyle with radiate operculum, placed on the oral pole of the main axis).

The genus Phceocolla may be regarded as the simplest form of all PH^EODARIA, and
perhaps as the common ancestral form of this legion. It has no skeleton, and the central
capsule exhibits only a single aperture on one pole of the main axis. In this it agrees
with the Challengerida, Medusettida, and Castanellida, which have also no parapylse or
secondary openings.

1. Phceocolla jyrimordialis, n. sp. (PL 101, fig. 1).

Central capsule subspherical, or somewhat depressed in the direction of the main axis. The
oral pole of the latter exhibits a large astropyle, or a radiate operculum, about as broad as the

1 PJueocolla = Brown jelly; <p«io';, xo'?,x».

REPORT ON THE RADIOLARIA. 1545

nucleus. From its centre arises a conical mammilla, prolonged into a thin, cylindrical, S-like tubulus,
the proboscis, which is about as long as the diameter of the capsule. The outer membrane of the
capsule is thick and double-contoured ; the inner is very thin, but distinct, and includes finely
granulated protoplasm, and numerous spherical, clear vacuoles, each with some small granules.
Nucleus spheroidal, depressed in the direction of the main axis, containing numerous dark, irregularly
amcebiform nucleoli. The diameter of the nucleus is about equal to the radius of the central capsule.
The extracapsular calymma is an alveolated sphere, the diameter of which is six to eight times that
of the capsule. The inner part of it contains an irregular, blackish phseodium, which surrounds and
hides the oral half of the central capsule.

Dimensions. — Diameter of the central capsule 016, of the nucleus 0'08, of the calymma
1-0 to 1-2.

Habitat. — Central Pacific, Station 271 to 274, surface.

Genus 657. Phceodina,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena,

Dec. 12, p. 4.

Definition. — P h se o d i n i d a with three apertures to the central capsule (an astropyle
on the oral pole of the main axis, and two lateral parapylse on both sides of the aboral
pole).

The genus Phceodina has the same structure of the central capsule as the majority of
PH^ODARIA ; one large main-opening or astropyle on the oral pole of the main axis, and
two smaller lateral accessory openings or parapylse on each side of the aboral pole : it is
therefore a true Tripylean genus, like the majority of PH^EODARIA.

1. Phceodina tripylea, Haeckel (PL 101, fig. 2).

? Tripylea sp., R. Hertwig, 1879, Organismus d. Radiol., Taf. x. figs. 1, 11.

Central capsule spheroidal or lenticular, somewhat depressed in the direction of the main axis.
Astropyle with a strongly ribbed, radiate operculum, scarcely one-third as broad as the diameter of
the capsule, and prolonged into a short tubular proboscis. Parapyke also with short tubular openings.
The outer strong (double-contoured) membrane of the central capsule is separated from the inner
thin (simple-contoured) membrane by a wide interval, filled up by a clear fluid or jelly ; only at
the three apertures both membranes are in direct connection. The granulated protoplasm contains
numerous vacuoles, and surrounds a large spheroidal nucleus, with numerous small nucleoli. The
voluminous calymma in a specimen, observed living, was alveolar, and the ramification of the
pseudopodia, as well as the formation of the dark brown phasodium, very similar to that of
Dictyocha stapedia (PI. 101, fig. 10). Another specimen, figured in PL 101, fig. 2, exhibited the first
stages of self-division; the reticulated nucleus and the .radiate operculum of the astropyle were
already doubled, and the two membranes of the capsule between them constricted in the median
plane. To this species belong probably the two central capsules figured by R Hertwig, loc. cit.

1 Phceodina = Provided with brown pigment ; (paiaoton.

(ZOOL. CHALL. EXP. PART XL. — 1886.) Rr 194

1546 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Diameter of the central capsule 015 to 0'25, of the nucleus 0'06 to 01, of the
calymma 0'8 to 1'2.

Habitat. — Mediterranean ; Portofino, near Genoa (Haeckel) ; Messina (Hertwig).

2. Phceodina cannopylea, n. sp.

Central capsule subspherical, scarcely depressed in the direction of the main axis. Astropyle
with a finely ribbed radiate operculum, about as broad as the radius of the capsule, prolonged into a
slender, tubular proboscis which is S-shaped, about as long as the radius, and similar to that of
Phceomlla primordialis, PI. 101, fig. 1. Parapylse also tubular, with two slender prolongations, half
as long and broad as the proboscis of the parapyle. Nucleus spheroidal, about half as broad as the
capsule. This species differs from the preceding mainly in the cylindrical slender prolongations of
the three apertures, which are similar to those of Aulosphcera and Aularia (PL 111, fig. 2).

Dimensions. — Diameter of the central capsule 0'2, of the nucleus 01, of the calymma 1/2 to 1/5.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Family LXXII. CANNORRHAPHIDA, Haeckel, 1879 (PI. 101, figs. 3-14 ;

PI. 114, figs. 7-13).

Cannorrhaphida, Haeckel, 1879, Sitzungsb. med.-nat. Gesollsch. Jena, Den. 12, p. 4.

Definition. — PH^EODARIA with an incomplete skeleton, composed of numerous separate,
not radially arranged pieces, which are either hollow tangential spicula or cap-shaped
dishes, or fenestrated rings, scattered loosely in the calymma. Central capsule placed
in the centre of the spherical calymma.

The family Cannorrhaphida comprises those PH^EODARIA in which the incomplete
skeleton is represented by numerous separate pieces of silica, which exhibit very different
forms, and are scattered tangentially on the surface of the spherical calymma, sometimes
also throughout its jelly-mass. They agree in this peculiar character with the
Thalassosphserida (among the SPUMELLARIA) and bear the same relation to the skeleton-
less Phseodinida as the Thalassosphserida do to the Thalassicollida (compare pp. 10 and
29). The Cannorrhaphida represent the former group among the PH^EODARIA. They
differ from the following family, the Aulacanthida, in the arrangement and position of
the hollow spicula, which are never directed radially and never touch the central capsule,
as is constantly the case in the latter.

Two genera of Cannorrhaphida have been hitherto known. The first species observed
in a complete and living state (at Messina in 1859) was Cannobelos cavispicula, described
in 1862 in my Monograph as Thalassoplancta cavispicula (foe. cit., p. 261, Taf. iii.
figs. 10-13). I there figured a complete living specimen with expanded pseudopodia and
a double central capsule (in the stage of self-division). The latter was surrounded by an

REPORT ON THE RADIOLARIA. 1547

alveolar calymma and by a voluminous mass of blackish-brown pigment, the phseodium ;
numerous, long, hollow, cylindrical tubes were scattered on the surface of the calymma.
At that time I did not know the tripylean character of the central capsule and the peculiar
radiate operculum in the PHyEODARiA, and therefore placed Thallassoplancta cavispicula
among the Thalassosphserida.

The second description of a complete form of Cannorrhaphida was given in 1879 by
R. Hertwig, under the name Dictyocha fibula (Organismus d. Radiol., p. 89, Taf. ix. fig. 5).
The genus Dictyocha had been already founded by Ehrenberg in 1838, with the following
definition : — " Lorica simplex, univalvis, silicea, laxe reticulata aut stellata " (Abhandl.
d. k. Akad. d. Wiss. Berlin, 1838, p. 128). Ehrenberg had found only scattered pieces
of the skeleton, fossil in Tertiary rocks. He placed them among the Bacillaria
( = Diatomaceas), but added, that they may be possibly scattered spicula of Sponges
(" forsan Spongiarum ossicula ").

In 1859 I myself observed similar forms of Dictyocha at Messina, and first recog-
nised them as true Radiolaria. But I placed them at that time among the Acantho-
desmida, beside Prismatium, supposing that a small spherical body which I had some-
times seen in the cavity of the pileated pieces (probably a phaeodellum) was the small
central capsule (Monogr. d. Radiol., 1862, p. 271, Taf. xii. figs. 3-6). The complete
body of Dictyocha was not described till 1879, when R. Hertwig gave a full descrip-
tion of its peculiar structure, and especially of the great central capsule, which resembles
that of the other PH^ODARIA. He first stated that the singular pileated pieces described
by Ehrenberg were not complete shells, but isolated pieces of the skeleton, which are
scattered in the jelly-envelope around the central capsule in a mode similar to the spicula
of Thalassoplancta, Thalassosphcera and Sphcerozoum. Hertwig also first recognised
that the thin rods, which compose the reticular pileated pieces of the skeleton in
Dictyocha, are not solid bars, but thin hollow tubules, similar to the hollow rods of
Aulacantha and of other PH^EODARIA.

Numerous complete and well-preserved specimens of Dictyocha, which I found in the
collection of the Challenger, have convinced me that the accurate description of
R. Hertwig is correct in every respect, and that these remarkable bodies are true
PUJEODARIA, most closely allied to Cannobelos ( = Thalassoplancta) and to Aulacantha
(compare PI. 101, fig. 10). I now regard them as representatives of a peculiar
subfamily of Cannorrhaphida, which I call Dictyochida. To the same subfamily also
belong the small annular bodies which Ehrenberg described in 1841 as Mesocena
(loc. cit., p. 401), and the elegant, more complicated, reticular and pileated bodies,
which Stohr figured in 1880 under the name Distephanus (Palasontogr., vol. xxvi.
p. 121). These peculiar bodies are also only isolated pieces of the siliceous skeleton, and
are scattered tangentially in great numbers in the calymma, around the tripylean central
capsule. A still higher degree of development is attained by the interesting forms

1548 THE VOYAGE OF H.M.S. CHALLENGER.

which I describe here as Cannopilus (PL 114, figs. 7-13). All these peculiar forms may
be derived from the simple annular pieces of skeleton, which are aggregated in great
numbers in the calymma of Mesocena. The pieces of the skeleton of these Dictyochida
never assume the form of slender, cylindrical, tangential tubules which is characteristic
of the Cannobelida,

A third subfamily of Cannorrhaphida, the Catinulida, is represented by the remark-
able new genus Catinulus (PL 117, fig. 8). The single pieces of the skeleton, scattered
in hundreds or thousands throughout the calymma, are here not composed of hollow
rods, as in the two former subfamilies, but are solid hemispherical caps, or small, more
flatly vaulted dishes, with a peculiar radial striation. All the complete specimens of
Catinulus which I could examine possessed four equal central capsules, united in one
spherical calymma.

The common character which unites the three rather different subfamilies, the
Cannobelida, Dictyochida and Catinulida, into a single family, and which separates this
family, the Cannorrhaphida, from the other PH^EODAEIA, is to be found in the composition
of the rudimentary skeleton from numerous single pieces, which are loosely scattered
either on the surface of the calymma, or throughout its jelly-mass, and which are never
arranged radially, and never touch the central capsule, as is always the case in the closely
allied Aulacanthida.

The slender spicula of the Cannobelida are cylindrical or spindle-shaped, tubular,
scattered in variable numbers, but always in a tangential direction on the surface of the
calymma. Usually they are 0'2 to 0'5 long, and 0'005 to 0'03 broad ; either straight or
slightly curved ; smooth and simple in Cannobelos, spiny or branched in Cannorrhaphis
(PL 101, figs. 3-5). Their wall is thin and fragile, their diameter sometimes equal
throughout their whole length, at other times tapering towards both ends. Their cavity
is filled by jelly, and seems to be open at both ends, since the purified and dried spicula
constantly become filled by air.

The peculiar pieces of silica which compose the skeleton of the Catinulida are not
hollow, like the rods of the other Cannorrhaphida, but concave hemispherical cups or more
flatly vaulted little dishes, the thin flinty wall of which is slightly thickened at the
circular margin, and radially striped above it. In all three species of Catinulus observed
they were scattered throughout the calymma in hundreds or thousands (PL 117, fig. 8).
Their relation to the Dictyochida is doubtful. Perhaps the small cups of Catinulus may
be derived from the simple rings of Mesocena, by development of an operculum on one
side of the ring.

The skeleton of the Dictyochida is much more developed and possesses a higher
morphological interest ; the numerous different forms, however, which its pieces here
assume, may be all derived from the simple circular ring of Mesocena. This ring is
formed by a thin, hollow, cylindrical, or prismatic rod, sometimes circular or elliptical, at

REPOKT ON THE RADIOLARIA. 1549

other times polygonal. From its margin small, hollow, radial spines often proceed
(PI. 101, fig. 9). In Dictyocha there arise from the ring two, three, four or more
siliceous bars or arches, which form one or more bridges over one side of the ring ;
usually the little fenestrated shell thus produced assumes the form of a three-sided or
four-sided pyramid, or of a little hat with three or four meshes (PI. 101, figs. 10-14).
From this Dictyocha (in a restricted sense) we separate the genus Distephanus, in which
the little pyramids become truncated, so that one central apical mesh (the apical or
upper ring) is surrounded by four, five, six or eight lateral meshes, the sides of the
pyramid (PI. 114, figs. 7-9). The edges of the small pyramid are formed by the same
number of siliceous bars arising from the ring and alternating with the meshes. Eadial
spines in different numbers and arrangements arise from the corners of the two parallel
rings, as well from the smaller apical as from the larger basal ring. The simple apical
ring of Distephanus becomes divided or fenestrated in the highest developed genus
of this subfamily, in Cannopilus (PL 114, figs. 10-13); each pileated piece of the
skeleton exhibits here two rows of alternating lateral meshes, an upper row of smaller and
a lower row of larger meshes.

The majority of Dictyochida are armed with spines or thorns, which, arise in a regular
manner from different points of the annular or pileated pieces. In the ancestral genus,
Mesocena, radial spines start from the corners of the simple ring in centrifugal direction,
and lie horizontally in its plane. As these primary corner-spines determine the radial
composition of the more highly developed genera we call them perradial (lying in rays of
the first order). In Dictyocha and Distephanus commonly (but not quite constantly) these
perradial spines alternate with the ascending bars which bisect the sides of the basal ring ;
these bars are therefore interradial (lying in rays of the second order) ; consequently also
the corners of the apical ring of Distephanus are interradial. The latter also often bear
small thorns or teeth. Other teeth frequently start in centripetal direction from the
lower or basal ring, on the side of the perradial spines, and frequently they are directed
obliquely downwards.

In Dictyocha and Distephanus are frequently found remarkable twin pieces, composed
of two pileated and reticulated skeleton pieces. These are united by their basal rings
loosely in such a way that they form together a small fenestrated subspherical body ;
the union is strengthened by those small teeth of the basal rings, which are directed
downwards and catch one into the other (PI. 101, fig. 12 ; PI. 114, fig. 8). A similar
twin piece has been already observed by Stohr in the fossil Distephanus rotundus, and
upon this was founded this genus. Since the teeth of the two opposed basal rings,
catching one into the other, seem to be specially adapted for the composition of those
small double pyramids, it is probable that the latter possess a special protective function
in these PHJSODARIA, and perhaps envelop their phaeodella or their flagellate spores (1).
In every case these formations are very remarkable.

1550

THE VOYAGE OF H.M.S. CHALLENGER.

The Central Capsule of the Cannorrhaphida seems to possess the same shape in the
three subfamilies, and to agree in general with that of the Aulacanthida. In a living
specimen of Dictyocha stapedia, which I observed at Ceylon (PL 101, fig. 10), the
three openings of the TRIPYLEA were distinct ; the radiate operculum of the astropyle
(on the oral pole) was surrounded by the granules of the dark phaeodium, whilst on
the opposite aboral side, two parapylse or conical secondary openings were visible. The
voluminous spherical calymma (about four times as broad as the central capsule) contained
numerous large alveoles (as in Aulosphcera) and its surface was protected by numerous
pileated pieces of the skeleton ; the basal ring of the latter was placed tangentially
in the spherical surface of the calymma, their apical spine being directed outwards
The pseudopodia, arising from the central capsule and forming a network between the
alveoles of the calymma, radiated outwards in great number from its surface (PI. 101,
fig. 10).

The propagation by self-division seems to be very frequent in the Cannorrhaphida,
I frequently found two equal central capsules in one calymma, as in the first observed
species, Cannobelos cavispicula, and in Cannorrhaphis spinulosa (PL 101, fig. 3),
sometimes also in Dictyocha and Distephanus. As already mentioned, Catinulus
constantly exhibited four central capsules united in each calymma.

I. Subfamily

Cannobelida.
Pieces of the skeleton
cylindrical or spindle-
shaped tangential
tubules.

II. Subfamily

Catinulida.

Pieces of the skeleton
hemispherical or cap-
shaped, solid.

III. Subfamily

Dictyochida.

Pieces of the skeleton
either simple rings
or pileated or pyra-
midal bodies, com-
posed of thin hollow
rods and reticular
meshes.

Synopsis of the Genera of Cannorrhaphida.

Tubules simple, smooth,
Tubules spiny or branched,

. 658. Cannobelos.
. 659. Cannorrhaphis.

Caps or hemispherical pieces of the skeleton solid, with radiate
margin and circular opening, ....

Flinty pieces simple or
arched rings, not trun-
cated pyramids, with a
basal ring, but without
apical ring.

Flinty pieces of the skeleton
resembling a truncated
pyramid, with an upper
smaller apical ring, and
a lower larger basal ring.

f Basal ring simple, not arched
or fenestrated,

Basal ring fenestrated, with
two or more arches, vaulted
over one side,

Apical ring simple, not fenes-
trated (one girdle of meshes
on each piece),

Apical ring fenestrated (two
girdles of meshes on each
piece),

660. Catinulus.

661. Mesocena.

662. Dictyocha.

663. Distephanus.

664. Cannopilus.

REPORT ON THE RADIOLARIA. 1551

Subfamily 1. CAXNOBELIDA, Haeckel.

Definition. — C annorrhaphida with numerous hollow cylindrical or spindle-
shaped tubes, which lie tangentially scattered on the surface of the spherical calymma.

Genus 658. Cannobelos,1 n. gen.

Definition. — C annorrhaphida with a skeleton composed of tubular acicular
pieces, which are smooth, cylindrical or spindle-shaped tangential needles, without spines
and branches.

The genus Cannobelos, and the following closely allied Cannorrhaphis, represent
the peculiar subfamily Cannobelida, differing from the other Cannorrhaphida in the
acicular form of the pieces of the skeleton, which are tangentially scattered on the
surface of the spherical calymma. The cylindrical or spindle-shaped hollow needles
are smooth in Cannobelos, whilst in Cannorrhaphis they are studded with lateral
spines or branches.

1. Cannobelos cavispicula, Haeckel.

Thalassoplancta cavispicula, Haeckel, 1862, Monogr. d. Radiol., p. 261, Taf. iii. figs. 10-13.
Tlialassicolla cavispicula, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 798.
Cannorrhaphis cavispicula, Haeckel, 1881, Prodromus, p. 470.

Tangential tubes cylindrical, more or less curved, gradually tapering towards the two pointed ends.
Calymma with a voluminous phpeodium.

Dimensions. — Length of the tubular spicule 0'25, breadth 0003.
Habitat. — Mediterranean, Messina, surface.

2. Cannobelos calymmata, n. sp.

Tangential tubes cylindrical, straight, of equal breadth throughout their whole length, closed by
a hemispherical cap on the two rounded ends. Calymma very voluminous, with a small phseodium.
Dimensions. — Length of the tubular spicula 03 to 0'5, breadth O004 to O'OOS.
Habitat. — Central Pacific, Stations 263 to 274, surface.

3. Cannobelos thalassoplancta, n. sp.

Tangential tubes spindle-shaped, straight, gradually tapering towards the two pointed ends.
Calymma and the included phteodium rather voluminous.

Dimensions. — Length of the tubular spicula 015 to 0'2, breadth in the middle part 0'02.
Habitat. — Tropical Atlantic, Station 347, surface.

1 Cannobelos = Bearing hollow tubular arrows ; xximot, ,

1552 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 659. Cannorrhaphis,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 4.

Definition. — C annorrhaphida with a skeleton composed of tubular acicular
pieces, which are spiny, cylindrical or spindle-shaped tangential needles, either with
lateral spines or branches.

The genus Cannorrhaphis differs from the preceding closely allied Cannobelos
in the spiny shape of the tangential acicular spicula, which are studded either with
short spines or with longer lateral branches.

1. Cannorrhaphis spinulosa, n. sp. (PI. 101, figs. 3, 4).

Tangential tubes cylindrical, straight, gradually tapering towards the two pointed ends, densely
studded with conical spines, arising perpendicularly. (The specimen figured, fig. 3, exhibited two
ovate central capsules, each of which contained two large nuclei, with numerous nucleoli.)

Dimensions. — Length of the tubular spicula 0'3 to 0'5, breadth O'Ol to O015.

Habitat. — North Pacific, Station 244, surface.

2. Cannorrhaphis lampoxanthium, n. sp.

Tangential tubes cylindrical, more or less curved, suddenly tapering towards the two pointed ends,
densely studded with irregular conical spines of unequal length, which arise obliquely from their
surface.

Dimensions. — Length of the tubular spicula 0'4 to 0-5, breadth O005 to O008.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

3. Cannorrhaphis lappacea, n. sp.

Tangential tubes spindle-shaped, gradually tapering towards the two pointed ends, densely studded
with irregular lateral branches, which are partly simple, partly forked, more or less curved, and
arise obliquely from their surface.

Dimensions. — Length of the tubular spicula 0'2 to 0'3, breadth 0'015 to 0'025.

Habitat. — Central Pacific, Station 271, surface.

4. Cannorrhaphis spathillata, n. sp. (PL 101, fig. 5).

Tangential tubes cylindrical, thin and straight, regularly zigzag, with pointed, regularly alternat-
ing lateral spines, with an elegant spathilla, or a cap-shaped verticil of eight to ten recurved spines
on the two ends.

Dimensions. — Length of the tubular spicula 0'3, breadth 0'003.

Habitat. — Indian Ocean, Cocos Islands (Eabbe), surface.

1 Cannorrhaphis-— Bearing hollow tubular needles ; xarra, ptttfii.

REPORT ON THE RADIOLARIA. 1553

Subfamily 2. CATINULIDA, Haeckel.

Definition. — C annorrhaphida with, a skeleton composed of numerous cap-
shaped pieces, which lie tangentially scattered on the surface of the spherical calymma.
Each piece is a hemispherical or flatly cap-shaped siliceous body, often with radial
striations, and with a thin solid wall.

Genus 660. Catinulus,1 n. gen.

Definition. — C annorrhaphida with a skeleton composed of solid, cap-shaped
or hemispherical, not fenestrated, pieces.

The genus Catinulus differs from all the other Cannorrhaphida in the peculiar
shape of the numerous siliceous pieces, which are scattered on the surface of the
calymma and compose their rudimentary skeleton. These pieces are neither hollow
rings (as in the Dictyochida), nor hollow tubes (as in the Cannobelida), but solid hemi-
spherical caps or more flatly vaulted small dishes. All the complete specimens of this
genus which I observed exhibited four equal central capsules in the spherical calymma.

1. Catinulus quadrifidus, n. sp. (PL 117, figs. 8, 8a).

I

Cap-shaped pieces of the skeleton flatly vaulted, three times as broad as high, smooth ; the
marginal ring with fine radial ribs and with smooth margin.

Dimensions. — Diameter of the calymma 0'6 to 0'8, of the four central capsules 012 to 0'2 ;
breadth of the concave caps 0'024, height O'OOS.

Habitat. — South Atlantic, Station 323, depth 1900 fathoms.

2. Catinulus catillum, n. sp.

Cap-shaped pieces of the skeleton flatly vaulted, three times as broad as high, rough, covered
with numerous small spinules ; the marginal ring with stout radial ribs and a corona of denticles
on the margin.

Dimensions. — Breadth of the concave caps 0'03, height O'Ol.

Habitat.-— South Atlantic, Station 332, depth 2200 fathoms.

3. Catinulus lopadium, n. sp.

Cap-shaped pieces of the skeleton hemispherical, twice as broad as high, smooth ; the marginal
ring smooth, slightly radiate, with thickened smooth margin.

Dimensions. — Diameter of the calymma 1'2, of the central capsule 0'22 ; breadth of the concave
caps 0-024, height 0'012.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

1 Catinulus = Small cup or dish.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 195

1554 THE VOYAGE OF H.M.S. CHALLENGER.

Subfamily 3. DICTYOCHIDA, Haeckel.

Definition. — C annorrhaphida with a skeleton composed of numerous annular
pieces, which lie tangentially scattered on the surface of the calymma. Each piece is
either a simple hollow ring or a pileate and reticulate cap, composed of a ring and
several connected bars.

Genus 661. Mesocena,1 Ehrenberg, 1841, Abhandl. d. k. Akad. d.

Wiss. Berlin, p. 401.

Definition. — C annorrhaphida with a skeleton composed of simple annular
pieces, each of which is a circular, elliptical or polygonal, not fenestrated, ring, with
or without radial spines.

The genus Mesocena is the simplest form of the Dictyochida, and no doubt the
common ancestral form of this subfamily. The siliceous pieces, which are scattered in
variable and indefinite number in the calymma, are simple hollow rings, with or with-
out spines on the periphery. Ehrenberg, who first described and figured such rings
(found fossil in different Tertiary rocks) has mistaken them for Diatoms. Some
species, which I found in the Challenger preparations, leave no doubt that these
rings are the siliceous pieces of the skeleton of the simplest Dictyochida. They are
scattered in great numbers in the spherical calymma, which surrounds a tripylean
central capsule with all the characters of the PH^ODARIA. In the living body the rings
probably always lie in the spherical periphery of the extracapsular jelly -veil, in
tangential planes, whilst in some of the Challenger preparations the rings were
scattered in hundreds throughout the whole jelly -mass. In a few species the rings
are quite simple, circular or elliptical, smooth, and without teeth or spines. In the
majority of species some teeth or radial spines, regularly disposed, arise from the
periphery of each ring (two, three, four to eight ; sometimes sixteen, eight smaller
alternating with eight larger spines). In some species small teeth occur on the
inner margin of the rings. The number of radial spines seems to be rather constant
in all the rings of one and the same individual, with the exception of a few variations.
Thus in Mesocena octogona I found here and there single rings with seven or nine
teeth, instead of the usual number eight. Ehrenberg enumerated sixteen different
species of Mesocena; many, however, of these are synonymous, being founded on slight
variations in the number of the teeth ; of others he has given only the name, but neither
a figure nor a description (e.g., Mesocena stephanolithis, Mesocena spongolithis, &c.).

1 Mesocena = Hollow in the centre, annular ; pi/jou, x,tsia;.

REPORT ON THE RADIOLARIA. 1555

1. Mesocena circulus, Ehrenberg.

Mesoeena circulus, Ehrenberg, 1840, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 208.
Mesocena circulus, Ehrenberg, 1854, Mikrogeol., Taf. xix. fig. 44.

Rings of the skeleton circular, smooth or slightly denticulate on the outer margin, without
spines. This simple form is probably the ancestral form of the Dictyochida.

Dimensions. — Diameter of the rings 0'02 to 0'03, thickness of the hollow rod O'OOl or less.

Habitat. — Fossil in Tertiary rocks of Barbados and of the Mediterranean ( Jigina, Greece ;
Caltanisetta, Sicily).

2. Mesocena annulus, n. sp.

1 Mesocena crenulata, Ehrenberg, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 822.

Kings of the skeleton elliptical, smooth or slightly denticulate on the outer margin, without
spines. This species is possibly identical with Mesocena crenulata of Ehrenberg, of which, however,
no figure is given. The major axis of the ellipse is one and a half times as long as the minor.

Dimensions. — Diameter of the rings in the major axis 0'03, in the minor 0'02 ; thickness of the
bars 0-002.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

3. Mesocena diodon, Ehrenberg.

Mesocena diodon, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 84.
Mesocena diodon, Ebrenberg, 1854, MikrogeoL, Taf. xxxiii., Nr. xv. fig. 18.

Rings of the skeleton elliptical, smooth, with two opposite spines on the poles of the major
axis, which is about one and one-third as long as the minor axis.

Dimensions. — Diameter of the rings in the major axis 0'04, in the minor 0'03 ; length of the
spines O'Ol.

Habitat. — Fossil in Barbados, and in North America (Virginia).

*

4. Mesocena triangula, Ehrenberg.

Mesocena triangula, Ehrenberg, 1840, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 208.
Mesocena triangula, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 41.
Dictyocha triangula, Ehrenberg, 1875, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 46.
Lithocircus trianyularis, Sto'hr, 1880, Palseontogr., vol. xxvi. p. 121, Taf. vii fig. 10.

Rings triangular, with small peripheral thorns, and three larger teeth on the corners of the
equilateral triangle.

Dimensions. — Diameter of the rings 0'03 to 0'05, length of the spines O'Ol.

Habitat. — Fossil in Tertiary deposits of the Mediterranean ; Caltanisetta, Sicily (Ehrenberg,
Stohr).

1556 THE VOYAGE OF H.M.S. CHALLENGER.

5. Mesocena quadrangula, Ehrenberg.

IMesocena quadrangula, Ehrenberg, 1872, Abhaudl. d. k. Akad. d. Wiss. Berlin, pp. 145, 273.
? Mesocena quaternaria, Ehrenberg, 1855, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 302.

Rings square, with four radial spines on the corners of the square. Ehrenberg has given only
the name of this species, but neither diagnosis nor figure. I think it may be identical with the
species described, which I found in the North Atlantic.

Dimensions. — Diameter of the rings 0'02 to O025, length of the spines O'OOT to O'Ol.

Habitat. — North Atlantic, Faeroe Channel, Gulf Stream (John Murray), depth 600 fathoms.

6. Mesocena elliptica, Ehrenberg.

Mesocena elliptica, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 84.
Mesocena elliptica, Ehrenberg, 1854, Mikrogeol., vol. i. Taf. xx. tig. 44.
Dictyocha elliptica, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 44.

Rings elliptical or ovate, with four peripheral spines which lie in two diameters, perpendicular
to one another, two opposite in the major, the two others in the minor axis of the ellipse.

Dimensions. — Diameter of the rings 0'015 to 0'03, length of the spines 0'005.

Habitat. — Fossil in Tertiary rocks of the Mediterranean (Placca di furni, from Zante, Greece) ;
Caltanisetta, Sicily.

7. Mesocena pentagona, n. sp.

Kings regularly pentagonal, with smooth straight bars, and with five short and straight radial
spines on the five corners.

Dimensions. — Diameter of the rings 0'02, length of the spines O'OOo.
Habitat. — Fossil in Barbados.

.8. Mesocena hexagona, Haeckel.

IMesocena senaria, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, pp. 163, 273.
1 Mesocena septenaria, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, pp. 163, 273.

Rings regular, hexagonal, with six radial spines on the six corners (sometimes between the
usual six-radiate rings of one and the same "individual are intermingled single rings with five or
seven spines).

Dimensions. — Diameter of the rings 0'025 to 0'03, length of the spines 0'007 to O'Ol.

Habitat. — Mediterranean, Krim (Ehrenberg), Corfu (Haeckel).

REPORT ON THE RADIOLARIA. 1557

9. Mesocena octogona, Ehrenberg.

Mesocena octogona, Ehrenberg, 1841, AbhandL d. k. Akad. d. Wiss. Berlin, p. 417, Taf. i.,
Nr. iii. fig. 27.

? Mesocena heptagona, Ehrenberg, 1841, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 417, Taf. i,

Nr. iii. fig. 26.

1 Mesocena heptagona, Ehrenberg, 1854, Mikrogeol., Taf. xx. fig. 49.

1 Mesocena octoradiata, Ehrenberg, 1872, AbhandL d. k. Akad. d. Wiss. Berlin, pp. 163, 273.
1 Mesocena nonaria, Ehrenberg, 1872, Abhandl. d. k. Akad. d. Wiss. Berlin, pp. 163, 273.

Kings regular, octogonal, with eight radial spines on the eight corners of the ring (sometimes
between the common octoradiate rings single rings with seven or nine teeth are intermingled in one
and the same calymrna).

Dimensions. — Diameter of the rings O02, length of the spines 0005.

Habitat. — Tropical Pacific; Peru, Ehrenberg ; Station 272 to 274, surface.

10. Mesocena bisoctona, Ehrenberg.

Mesocena bisoctona, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 78;

Mikrogeol., Taf. xxxv., Nr. xviii. figs. 9, 10.
Mesocena binonaria, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 78,

loc. cit.

Pangs circular, with sixteen teeth ; eight stronger teeth regularly disposed on the outer margin,
alternating with these eight smaller teeth on the inner margin.

Dimensions. — Diameter of the rings 0'02, length of the outer spines O'OOS.
Habitat. — Fossil in Guano from Peru and South Africa, also in Barbados.

11. Mesocena stellata, n. sp. (PL 101, fig. 9).

Eings circular, with sixteen teeth regularly disposed on the outer margin of the rings, eight
stronger teeth alternating with eight smaller.

Dimensions. — Diameter of the rings O'OS, length of the larger spines O'Ol.
Habitat. — Central area of the Pacific, Station 270, depth 2925 fathoms.

Genus 662. Dictyocha,1 Ehrenberg, 1838, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 128.

Definition. — C annorrhaphida with a skeleton composed of annular pieces,
which are fenestrated by one or more arches, arising on one side of the simple ring, but do
not form a truncated pyramid (therefore no apical ring).

The genus Dictyocha is a very remarkable and interesting form of PH^EODAKIA, which
has had a curious history. Ehrenberg, who first observed single pieces of it fossil in
Tertiary rocks, supposed it to be the siliceous carapace of a Diatom, and gave it the following

1 Dictyocha = Net-possessing; S/XTUOK, t-^u.

1558 THE VOYAGE OF H.M.S. CHALLENGER.

diagnosis : " Dictyocha, e familia Bacillariorum. Lorica simplex univalvis silicea, laxe
reticulata aut stellulata" (loc. cit.). In my Monograph (1862, p. 271), I placed it in the
class Radiolaria, supposing that it might be a simple form of Acanthodesmida, having
found only isolated siliceous pieces. Afterwards (in 1879) Richard Hertwig observed the
entire living body, and demonstrated that the hollow siliceous pieces are scattered in
great numbers around a tripylean central capsule, which exhibits all the essential characters
of PHJEODARIA (Organismus d. Radiol., 1879, p. 89). Hertwig describes the position of
the numerous siliceous pieces in the surface of the extracapsular jelly-sphere so densely
aggregated, that they touch one another and produce the appearance of a reticulated
sphere. In two specimens, which I observed living (PL 101, fig. 10), and in numerous
complete specimens which I found in the collection of the Challenger, the number of the
siliceous pieces was much smaller, and they were scattered irregularly in the surface of the
alveolate jelly-sphere, being separated by wide and unequal intervals. The regular position
seems to be that the basal rings lie tangentially in the spherical surface of the calymma,
whilst the bars of the reticulum are directed outwards, and the apical spine radially in
centrifugal direction. Very often two pieces are united by their basal rings in such a
manner that they form a little spheroidal fenestrated body (as in Distephanus, Stohr ;
compare p. 1550). The characteristic reticular skeleton-pieces of Dictyocha must be
derived from Mesocena ; from its simple siliceous ring (on one side of its plane), arise
two, three, or four (rarely more) bars, which become united to a loose framework (with
two, three, or four meshes). When this network assumes the form of a truncated pyramid
(with a central mesh on the apex), Dictyocha passes over into Distephanus. From the
corners of the original basal ring several radial spines usually arise in a centrifugal direc-
tion, and on the sides of these sometimes small teeth or thorns also run in a centripetal
direction. The number of the meshes and the separating rods is usually four, more rarely
two or three. The hollow rods are very thin, either cylindrical or prismatic. As the
ascending rods alternate regularly with the corner-spines of the basal ring, we may call the
latter perradial, the former interradial. Ehrenberg has distinguished in his genus
Dictyocha not less than fifty species, thirty-five living and twenty-five fossil (ten species
both living and fossil). The greater part of these cannot be retained, as they are only
slight varieties or abnormalities of single pieces of the skeleton, such as very frequently
occur associated with the common regular forms in one and the same individual. Such
abnormal species are, e.g., Dictyocha abnormis, Dictyocha binoculus, Dictyocha bipartita,
Dictyocha haliomma, Dictyocha hexathyra, Dictyocha septenaria, Sec. One species (Dicty-
ocha splendens), is the fenestrated calcareous body of a Holothurian. Of some other species
Ehrenberg has only given the name, but neither a description nor a figure (e.g., Dictyocha
borealis, Dictyocha cenostephania, Dictyocha compos, Dictyocha coronata, Dictyocha
socialis, Dictyocha specillum). A number of other species must be placed in the genera
Distephanus and Cannopilus, so that only eight of his species of true Dictyocha remain.

.: REPORT ON THE RADIOLARIA. 1559

1. Dictyocha navicula, Ehrenberg.

Dictyocha navicula, Ehrenberg, 1838, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 129 ;

Mikrogeol., Taf. xx., Nr. i. fig. 43.
Dictyocha ponticulus, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 267.

Each individual ring elliptical or oblong, with one transverse arch in the shorter axis, which
bisects it into two meshes. No spines or teeth.

Dimensions. — Diameter of the ring 0'02, of the bars O'OOl.

Habitat. — Fossil in Tertiary deposits, Barbados, Sicily, &c. ; living in the Atlantic, Stations 352,
354, and off Bermuda, surface.

2. Dictyocha quadrala, Ehrenberg.

Dictyocha quadrata, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 267.

Each individual ring square or rhomboid, with one transverse arch in the shorter axis, forming
two meshes. Two peripheral opposite spines on the poles of one axis.
Dimensions. — Diameter of the ring 0'015.
Habitat. — Atlantic, Bermuda Islands ; fossil in Barbados.

3. Dictyocha pons, Ehrenberg.

Dictyocha pons, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 80 ;

Mikrogeol., Taf. xxi. fig. 40.
Dictyocha tripyla, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. BerKn, p. 80 ;

Mikrogeol., Taf. xxi. fig. 41.

Each individual ring elliptical or oblong, with one transverse arch in the shorter axis, forming
two meshes. Four peripheral spines, on the poles of the longer and of the shorter axis. (The
individual abnormality, figured as Dictyocha tripyla, loc. cit., Taf. xxi. fig. 41, has the transverse arch
bifid at one end, therefore three meshes result ; this forms an interesting transition to Dictyocha fibula.)

Dimensions. — Diameter of the ring O'Ol, of the bars O'OOl.

Habitat. — Fossil in Tertiary rocks, Oran, Africa.

4. Dictyocha triommata, Ehrenberg.

Dictyocha triommata, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 76 ;

Mikrogeol., Taf. xxxiii., Nr. xv. fig. 11.
Dictyocha triactis (-triacantha), Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss.

Berlin, p. 80.
Dictyocha trifenestrata, Ehrenberg, 1841, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 410 ;

Mikrogeol., Taf. xix. fig. 38.
Dictyocha abyssorum, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 38.

Each pileated piece of the skeleton is a small three-sided pyramid, the sides of which form three
triangular meshes ; the three edges between them are three curved interradial beams, united in the

1560 THE VOYAGE OF H.M.S. CHALLENGER.

centre (the apex of the pyramid). Alternating with these, three horizontal, perradial, centrifugal
spines start from the base.

Dimensions. — Diameter of the basal triangle O'Ol, of the three meshes 0'005.

Habitat. — Fossil in different Tertiary deposits (of Sicily, Greece, North America); living in the
Central Pacific, Stations 270 to 272, depth 2600 to 2925 fathoms.

5. Dictyocha tripyla, Ehrenberg.

Dictyocha tripyla, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 80.
Dictyocha tripyla, Ehrenberg, 1854, Mikrogeol., Taf. six. fig. 38 (et Taf. xxi.'fig. 41?).

Each pileate piece of the skeleton is a small three-sided pyramid, similar to that of
Dictyocha triommata, but differs from it in the possession of three small perpendicular teeth,
which are directed downwards and start from the basal ring near the origin of the three horizontal
spines.

Dimensions. — Diameter of the triangular basal ring 0'015, of the three meshes 0'007.

Habitat. — Fossil in Tertiary deposits, North Africa (Oran), Sicily (Caltanisetta).

6. Dictyocha medusa, n. sp. (PI. 101, figs. 13, 14).

Each pileated piece of the skeleton has four equal, cruciate, triangular meshes. From the four
corners of the square basal ring proceed four perradial horizontal spines, and between these four
interradial curved bars, which correspond to the edges of a four-sided pyramid, arise from the
centre of the four sides and become united in the centre (on the apex of the pyramid). No apical
spine.

Dimensions. — Diameter of the basal ring 0'02, of the four meshes O'Ol.

Habitat. — Central area of the Pacific, Station 272, depth 2600 fathoms.

7. Dictyocha staurodon, Ehrenberg.

Dictyocha staurodon, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 80.
Dictyocha staurodon, Ehrenberg, 1854, MikrogeoL, Taf. xviii. fig. 58.

Each pileated piece of the skeleton is a small, regular, four-sided pyramid, similar to the fore-
going species. It differs from Dictyocha medusa in the development of a vertical apical spine, and
of four small centripetal teeth, which start from the inside of the basal square, between the four
perradial spines and the four ascending interradial beams.

Dimensions. — Diameter of the basal ring 0'025, of the meshes O'Ol.

Habitat. — Fossil in Tertiary rocks ; Tripel of Richmond, Virginia (Ehrenberg) ; Barbados,
(Haeckel) ; living in the Tropical Atlantic, Station 347, surface.

REPORT ON THE RADIOLARIA. 1561

8. Dictyocha fibula, Ehrenberg.

Dictyocha fibula, Ehrenberg, 1839, Abhandl. d. k. Akad. d. Wiss. Berlin, p. 149; Mikrogeol.,
Taf. xviii. fig. 54, a, b, c, Taf. xix. fig. 43, Taf. xx. fig. 45, Taf. xxi. fig. 42, &c.

Dictyocha abnormis, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 76 ;
Mikrogeol., 1854, Taf. xxxvA., NT. xvii. fig. 9.

Dictyoclia bipartita, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 44.

Dictyocha tenella, Ehrenberg, 1841, Abhandl. d. k. Akad. d. Wiss. Berlin, Taf. ii. fig. 11.

Each pileated piece of the skeleton stirrup-shaped, with two pairs of meshes, and a square
basal ring, the four corners of which are prolonged into four perradial spines. Between the latter
four iuterradial beams arise from the sides in pairs, and the two pairs are connected by a diagonal
arch. Therefore the two opposite meshes are larger and pentagonal, the other two meshes
(alternating with these) are smaller and square. No vertical spine on the apex.

Dimensions. — Diameter of the basal square ring (diagonal) O'Ol to 0'02, of the meshes O'OOo.

Habitat. — Fossil in different Tertiary rocks (Barbados, Oran, Greece, Sicily, &c.), Ehrenberg.

9. Dictyocha messanensis, Haeckel.

Dictyocha messanensis, Haeckel, 1S62, Monogr. d. Radiol., p. 272, Taf. xii. figs. 3-6.
Dictyocha fibula, "R. Hertwig (not Ehrenberg), 1879, Organismus d. Radiol., p. 89, Taf. ix. fig. 5.

Each pileated piece of the skeleton stirrup-shaped, very similar to Dictyocha fibula, but dis-
tinguished by a vertical apical spine in the centre of the transverse arch, which connects the two
pairs of ascending bars.

Dimensions. — Diameter of the basal ring 0'02 to 0'03, of the meshes O'Ol to O'OIG.

Habitat. — Mediterranean (Messina), North Atlantic (Canary Islands), Station 354, surface.

10. Dictyocha epiodon, Ehrenberg.

Dictyocha epiodon, Ehrenberg, 1 844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 79 ;
MikrogeoL, Taf. xviii. fig. 55.

Each pileated piece of the skeleton stirrup-shaped, with four paired meshes similar to the hats
of Dictyoclia, fibula, but distinguished by four small centripetal thorns, which start from the inside of
the basal ring, at the side of the four ascending beams. No apical spine.

Dimensions. — Diameter of the basal ring 0'03, of the meshes O'Ol.

Habitat. — Fossil in Tertiary rocks of North America (Miocene Tripel of Eichmond, Virginia, &c.).

11. Dictyocha stapedia, n. sp. (PI. 101, figs. 10-12).

Each pileated piece of the skeleton stirrup-shaped, with four paired meshes, similar to the hats
of Dictyocha fibula and Dictyocha messanensis, but distinguished by four small centripetal teeth, which
start from the inside of the basal ring, at the side of the four ascending beams. In the centre of the
diagonal arch arises a vertical apical spine (differing from Dictyocha epiodon). This species seems

(ZOOL. CHALL. EXP. PART XL. 1886.) Rr 196

1562 THE VOYAGE OF H.M.S. CHALLENGER.

to be the most common of the living forms and widely distributed over all warmer seas. I observed
in Ceylon, taken on the surface, the living specimen figured in PI. 101^ fig. 10 ; the numerous
spicula were irregularly scattered over the spherical surface of the alveolate calymma. Other
specimens occur in various preparations of the Challenger collection, from the Atlantic and the
Pacific. The majority of the siliceous little hats exhibited the stirrup-form shown in fig. 11, and
many were united in pairs, forming a twin-piece (fig. 12). Intermingled with these are found some
irregular forms, representing the specific form of some allied species, viz., Dictyocha speculum,
Dictyocha staurodon, Dictyocha epiodon and Dictyocha messanensis.

Dimensions. — Diameter of the basal ring 0'015 to 0'03, of the meshes 0'005 to 0'012.

Habitat. — Cosmopolitan ; Atlantic, Pacific, Indian Ocean, in the Tropical and warmer regions ;
Stations 159, 244, 266-272, 318, 352, &c.

12. Dictyocha rhombus, n. sp.

Each pileated piece of the skeleton stirrup-shaped, similar to Dictyocha stapedia, with four
paired meshes. It differs from the latter in the rhomboid form of the basal ring and the larger
size of the two opposite meshes, which are two to three times as large as the two others. There-
fore the four centripetal teeth of the basal ring do not stand in the four single meshes, but in pairs
only in the two larger meshes.

Dimensions. — Diameter of the basal ring 0'02, of the meshes 0'005 to O'Ol.

Habitat. — North Atlantic; Faroe Channel, Gulf Stream, depth 50 to 600 fathoms, John Murray.

Genus 663. Distephanus,1 Stohr, 1880, Palseontogr., vol. xxvi.

Taf. ii. p. 121.

Definition. — C annorrhaphida with a skeleton composed of pileated pieces, each of
which is a small truncated pyramid with one girdle of meshes (the apical ring being simple).

The genus Distephanus was founded in 1880 by Stohr (loc. cit.) for a single twin-
piece of the skeleton of Dictyocha speculum. Among the common fossil forms of
this species he once found in the Tertiary rocks of Caltanisetta, Sicily, a single piece
(loc. cit., Taf. vi. fig. 9), which seemed to be composed of two equal pieces so united that
they formed a little sphere with fourteen meshes ; on each pole of the sphere lies a
central hexagonal mesh surrounded by six pentagonal meshes, and from the six
corners of the equatorial ring arise six centrifugal spines. No doubt this was a
mistake, and the apparent little sphere was one of the above mentioned twin-forms,
composed of two separate hexagonal truncated pyramids, which were loosely connected
by their basal rings. I have often seen such twin-pieces of Dictyocha speculum and of
other species (PL 101, fig. 12 ; PL 1 14, fig. 8), and was always able to separate the two
loosely connected halves of the bivalve shell by slight compression.

1 Distephanus = Double corona ;

REPORT ON THE RADIOLARIA. 1563

The genus Distephanus of Stohr, therefore, is nothing other than the Dictyocha of
Ehreiiberg. But I think it is more convenient to retain the name Distephanus for those
forms of Dictyocha which possess a simple apical mesh surrounded by a ring of lateral
meshes, and in which each piece of the skeleton forms a small truncated pyramid. The
basal plane of this pyramid is marked by the original basal ring (Mesocena), the truncated
upper plane by the parallel apical ring, and the edges of the pyramid by the rising bars
which connect both rings. In this sense, so far as the two rings lying in parallel planes
are concerned, the term Distephanus is correct (but not in the original sense of Stohr).
The number of the rising bars between the two rings varies from four, five, six to eight
or more. It seems rather constant in each species, so that all the pieces of the skeleton
of one specimen possess either four or six or eight lateral meshes, &c. But sometimes
individual irregularities occur. In the majority of species each skeleton-piece is armed
with spines. Usually a radial horizontal spine starts centrifugally from each corner of
the basal ring, and on the side of this a small tooth or thorn often starts centripetally or
downwards. In the twin-pieces, where the two basal rings are united, these teeth catch
into one another. In some species upper spines also occur, starting from, the corners of
the apical ring. The perradial spines of the corners of the basal ring alternate regularly
with the interradial ascending bars, which bisect the sides of the ring, as in Dictyooha.

1. Distephanus crux, Haeckel.

Dictyocha crux, Ehrenberg, 1840, Monatsber. d. k. preuss. Akad. d. "Wise. Berlin, p. 207;

Mikrogeol., 1854, Taf. xviii. fig. 56, Taf. xx. fig. 46, Taf. xxxiii. Nr. xv. fig. 9.
Dictyocha bipartita, Ehrenberg, 1844, loc. cit., p. 79, Taf. xxii. fig. 44.

Each pileated piece of the skeleton exhibits four pentagonal lateral meshes around one square
central mesh, and is composed of two horizontal square rings ; the smaller upper square is connected
with the larger lower square by four ascending interradial beams, which start from the corners of the
former and bisect the sides of the latter ; from the corners of the basal ring arise four short
perradial spines.

Dimensions. — Diameter of the basal ring 0'02 to 0'03, of the apical ring O'OOS.

Habitat. — Tropical Atlantic, Station 347, surface ; fossil in Tertiary deposits of the Mediter-
ranean (Sicily, Oran).

2. Distephanus mesophthalmus, Haeckel.

Dictyocha mesophthalma, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 80; Mikrogeol., 1854, Taf. xxii. fig. 43.

Each pileated piece of the skeleton exhibits four lateral meshes around the central mesh, and is
composed of two parallel horizontal square rings, like those of Disteplumm crux, but distinguished

1564 THE VOYAGE OF H.M.S. CHALLENGER.

from this by eight short teeth, four centripetal on the larger lower ring and four perradial centri-
fugal on the smaller upper ring.

Dimensions. — Diameter of the basal ring 0'03, of the apical ring 0'015.

Habitat. — Fossil in Tertiary rocks of Sicily, Caltanisetta (Ehrenberg) ; living in the Central
Pacific, Station 270 to 272, surface.

3. Distephanus staur acanthus, Haeckel.

Dictyocha stauracantlius, Ehrenberg, 1845, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 76 ;
MikrogeoL, 1854, Taf. xxxiil, Ni. xv. fig. 10.

Each pileated piece of the skeleton exhibits four lateral meshes around the central mesh, and is
composed of two horizontal rings, which are connected by four perradial beams arising from the
corners of the upper and smaller square ring. Lower ring octagonal, with eight peripheral adradial
spines, and with four interradial centripetal teeth on the inside.

Dimensions. — Diameter of the basal ring 0'02, of the apical ring 0'004.

Habitat. — Fossil in Tertiary rocks of North America (Hollis Cliff, Virginia ; Norwich,
Connecticut).

4. Distephanus asteroides, n. sp.

Dictyocha asteroides, Haeckel, 1881, Prodromus.

Each pileated piece of the skeleton exhibits five lateral meshes around the central mesh (or the
upper ring). Five peripheral spines (on the corners of the lower ring) simple, not articulated.
Dimensions. — Diameter of the basal ring 0'02, of the apical ring, 0'007.
Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

5. Distephanus pentasterias, Haeckel.

Dictyocha pentasterias, Ehrenberg, 1839, MikrogeoL, Taf. xviii. fig. 61.

1 Dictyocha quinaria, Ehrenberg, 1842, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 265.
1 Dictyocha elegans, Ehrenberg, 1844, Monatsber. d, k. preuss. Akad. d. Wiss. Berlin, p. 80 ;
MikrogeoL, 1854, Taf. xxii. fig. 51.

Actiniscus elegans, Ehrenberg, 1854, MikrogeoL, Taf. xxii. fig. 51.

Each pileated piece of the skeleton exhibits five lateral meshes around the central mesh (or the
upper ring). Five peripheral spines (on the corners of the lower ring) articulated, triangular, with
three distinct joints (tapering towards the distal end).

Dimensions. — Diameter of the basal ring 0'012 to 0-018, of the apical ring 0'002 to O'OOS.

Habitat. — Cosmopolitan ; living in the depths of the Atlantic and Central Pacific, Stations 247,
270 to 272, depths 2530 and 2600 to 2925 fathoms ; fossil in Tertiary deposits (Tripel of Cal-
tanisetta, Sicily ; Richmond, Virginia).

REPORT ON THE RADIOLARIA. 1565

6. Distephanus speculum, Haeckel.

Dictyoclm speculum, Ehrenberg, 1837, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 150;
Mikrogeol., 1854, Taf. xviii. fig. 57, Taf. xix. fig. 41, Taf. xxi. fig. 44, Taf. xxii. fig. 47, &c.
Dictyocha speculum, Stohr, 1880, Palteontogr., vol. xxvi., Taf. vii. fig. 8.
Dictyocha anacantha, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 238.
Dictyocha diommata, Ehrenberg, 1854, Mikrogeol., Taf. xxxiii., NT. xvii. fig. 6.
Dictyoclia erebi, Ehrenberg, 1854, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 238.
Dictyocha haliomma, Ehrenberg, 1844, Mikrogeol., 1854, Taf. xxi. fig. 46.
Dictyoclia liexathyra, Ehrenberg, 1844, Mikrogeol., 1854, Taf. xxii. fig. 46.
Dictyoclia ubera, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 80.
Dictyocha stella, Ehrenberg, 1854, Mikrogeol., Taf. xxii. fig. 52.
Distephanus rotundas, Stohr, 1880, Paleeontogr., vol. xxvi., Taf. vii. fig. 9.

Each pileated piece of the skeleton is a truncated, six-sided pyramid, and composed of two
regular hexagonal rings which lie in parallel plains, and are connected by six ascending interradial
beams ; these start from the corners of the upper smaller ring and bisect the sides of the lower
larger ring ; from the corners of the latter start six perradial centrifugal spines.

Dimensions. — Diameter of the basal ring 0'03, of the apical ring O'Ol.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific ; fossil in Barbados, Sicily, &c.

7. Disteplianus ornamentum, Haeckel.

Dictyocha ornamentum, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 80;

Mikrogeol., 1854, Taf. xxii. fig. 49.
Dictyocha linoculus, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 79;

Mikrogeol., 1854, Taf. xix. fig. 42.

Each pileated piece of the skeleton is a truncated, six-sided pyramid, similar to that of
Distephanus speculum, but distinguished by six small (probably vertical) teeth, which start from the
inside of the lower (larger) ring, on the sides of the ascending beams.

Dimensions. — Diameter of the basal ring 0'03, of the apical ring 0'015.

Habitat. — Fossil in Tertiary deposits of Sicily, Caltanisetta (Ehrenberg).

8. Distephanus aculeatus, Haeckel.

Dicti/ocha aculeata, Ehrenberg, 1839, Abhandl. d. k. preuss. Akad. d. Wiss. Berlin p. 149 .

Mikrogeol., 1854, Taf. xxii. fig. 48, Taf. xix. fig. 40.

Dictyocha aculeata, Stohr, 1880, Palseontogr., voL xxvi. p. 120, Taf. vii. fi<r. 7.
Dictyocha bisternaria, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 201.

Each pileated piece of the skeleton is a truncated, six-sided pyramid, similar to that of
Distephanus speculum, but distinguished by six small perradial, horizontal teeth, which start from the
sides of the upper (smaller) ring.

Dimensions. — Diameter of the basal ring 0'02, of the apical rin" O'OOS.

Habitat. — Fossil in Tertiary deposits of the Mediterranean; plastic clay of Greece and
Sicily; living in the Mediterranean and the Atlantic, Station 352, surface.

1566 THE VOYAGE OF H.M.S. CHALLENGER.

9. Distephanus sirius, Haeckel.

Actiniscus sirius, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 68.
Dictyocha sirius, Ehrenberg, 1854, Mikrogeol., Taf. xviii. fig. 59.

Each pileated piece of the skeleton is a truncated 'six-sided pyramid, similar to that of
Distephanus speculum, but distinguished hy the six broad, triangular, peripheral spines, which are
articulated and connected by a thin siliceous membrane (like a web-membrane) ; each spine has
three articulations (as in Dictyocha pentasterias).

Dimensions. — Diameter of the basal ring 0'02, of the apical ring 0005.

Habitat. — Fossil in Tertiary rocks (Eichmond, Virginia), but also living in the Atlantic Ocean,
Gulf Stream, Fgeroe Channel, John Murray, 1880.

10. Distephanus corona, n. sp. (PI. 114, figs. 7—9).

Dictyocha corona, Haeckel, 1881, Prodromus.

Each pileated piece of the skeleton is a truncate six-sided pyramid, like that of Distephanus
speculum, but differing in the number (twenty-four) of teeth or spines. Six interradial ascending
beams connect the two horizontal rings between these, and six nearly vertical spines arise from the
perradial corners of the upper hexagonal ring. In the same meridional (perradial) plains six larger
Spines descend downwards from the corners of the lower larger ring. Between these six descending
spines and the six ascending beams arise from the upper edge of the lower ring twelve shorter
teeth of unequal size (the right tooth in each pentagonal lateral mesh being smaller, and directed
upwards, the left tooth being larger and directed nearly horizontally outwards). The lower ring
is nearly dodecagonal.

Dimensions. — Diameter of the basal ring 0'025 to 0'03, of the apical ring 0'012 to 0'02.

Habitat. — North-west Pacific, Sea of Japan, Station 231, depth 2250 fathoms.

11. Distephanus octonarius, Haeekel.

Dictyocha octonaria, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 201.
Dictyocha polyactis, Ehrenberg, 1844, loc. cit., p. 80; Mikrogeol., 1854, Taf. xxii. fig. 50.
Dictyocha septenaria, Ehrenberg, 1844, loc. cit., p. 80; MikrogeoL, 1854, Taf. xxi. fig. 45.

Each pileate piece of the skeleton is a truncated eight-sided pyramid, composed of two regular
octagonal rings, which lie in parallel plains and are connected by eight radial beams. From the
eight outer corners of the lower ring (or from the eight interradial meshes, between the eight
perradial beams) start eight basal centrifugal spines. (This species is similar to Distephanus speculum,
but has eight beams instead of six. In single pieces the number of the beams and meshes varies
between seven and nine, the constant number being eight.) A seven-rayed variety is Dictyocha
septenaria (loc. cit.'), a nine-rayed Dictyocha polyactis.

Dimensions. — Diameter of the basal ring 0'02 to 0'03, of the apical ring O'Ol to 0'015.

Habitat. — Fossil in Tertiary rocks (Tripel and Marne from Caltanisetta, Sicily; Oran, Africa);
living in the depths of the Atlantic, Station 348, and Pacific, Station 270, &c.

REPORT ON THE RADIOLARIA. 1567

12. Distephanus octogonius, n. sp.

Dictyocha septenaria, Ehrenberg, 1854, Mikrogeol., Taf. xxxvA., Nr. xxi. fig. 8.

Each pileated piece of the skeleton is a truncated eight-sided pyramid, like that of Distephanus
octonarius, but differs from it by having eight short erect teeth, which arise from the corners of the
upper smaller ring and lie in the same perradial plains as the eight horizontal spines starting from
the corners of the lower larger ring. (Ehrenberg has figured only an individual abnormality with
seven beams instead of eight, taken from the Antarctic ice ; but I found the same form frequent
in deep-sea soundings from the Antarctic, almost constantly with eight beams, isolated hats with
six, seven, or nine beams being intermingled.

Dimensions. — Diameter of the basal ring 0'02, of the apical ring 0'012.

Habitat. — Antarctic Ocean ; in smolten " Pancake-Ice," taken by Sir James Clark Eoss in
lat. 78° 10' S., long. 162° W. (Ehrenberg) ; Station 156, depth 1975 fathoms.

13. Distephanus diadema, n. sp.

Dictyocha diadema, Haeckel, 1881, Prodromus.

Each pileated piece of the skeleton is an eight-sided pyramid, like that of the two foregoing
species, but differing in the number and distribution of the teeth or spines, which are thirty-two.
From the eight corners of the basal ring start eight long, nearly horizontal perradial spines, which
bear on each side a smaller, nearly vertically descending spine. From the eight corners of the
upper ring ascend also eight perradial spines, alternating with the eight interradial beams, which
connect the two rings.

Dimensions. — Diameter of the basal ring 0'04, of the apical ring 0'02.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

Genus 664. Cannopilus,1 n. gen.

Definition. — C annorrhaphida with a skeleton composed of pileated pieces,
each of which is a small truncated pyramid with two girdles of meshes (the apical
ring being fenestrated).

The genus Cannopilus represents the most highly developed form of Dictyochida.
Each piece of the skeleton is a little fenestrated hat or topped pyramid, as in Diste-
phanus. But the apical mesh is simple in the latter, in the former it is divided into
several meshes by bars which start in a centripetal direction from the upper ring. There-
fore we find two annular rows of meshes, one above the other ; an apical or upper row
of smaller meshes and a basal or lower row of larger meshes. In the apex of the little

1 Cannopilus = Hat with tubes ; zaim

1568 THE VOYAGE OF H.M.S. CHALLENGER.

hat is either a central mesh or an apical spine. Other spines arise from the basal ring,
as in the former genera. The number of corner-spines on the basal ring is either four,
six, or eight (in individual abnormalities also five or seven).

1. Cannopilus super structus, Haeckel.

Dictyocha superstructa, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 80;
Mikrogeol., Taf. xxii. fig. 45.

Each pileated piece of the skeleton is a reticulated four-sided pyramid. The base of it (or the
lower ring) is a square, from the four perradial corners of which start four centrifugal horizontal
spines. In the centres of the four basal bars (or the sides of the square) arise four interradial beams,
which unite in the second (or upper) square ring. This latter forms a second (but much smaller)
four-sided pyramid, the apex of which is truncated. Therefore the little hat bears nine meshes ;
around the large central opening four upper smaller and four lower larger quadrangular meshes.

Dimensions. — Diameter of the basal ring 0'03, of the apical ring O'Ol.

Habitat. — Fossil in Tertiary rocks of Sicily (Caltanisetta).

2. Gannopilus diplostaurtts, n. sp. (PL 114, fig. 10).

Each pileated piece of the skeleton is a truncated quadrangular pyramid. From the corners of
the square basal ring start four perradial, nearly horizontal, spines. Between these arise four inter-
radial beams, which are united above by an upper square ring. This latter is divided into four
small square meshes by a regular cross of perradial bars, the distal ends of which are prolonged
into four short ascending spines. In the centre of the cross arises a vertical apical spine.

Dimensions. — Diameter of the basal ring 0'04, of the apical ring O'OIG.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

3. Cannopilus calyptra, Haeckel.

Dictyocha Jieptacanthus, Ehrenberg, 1840, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin,
p. 203; Mikrogeol., 1854, Taf. xix. fig. 39 (?).

Each pileated piece of the skeleton is a truncated six-sided pyramid, like that of Dictyocha
speculum, but distinguished by the reticulation of the upper (smaller) ring, which is divided by six
beams into six meshes, lying in the horizontal plane of the upper ring. Six peripheral spines on
the corners of the lower ring. (The irregular form, figured by Ehrenberg as Dictyocha heptacanthus,
loc. cit., is probably only an individual abnormality with seven peripheral spines, instead of six ;
similar abnormalities occur also among the regular hexagonal forms which I found in the Tertiary
rocks of Caltanisetta (Sicily).

Dimensions. — Diameter of the basal ring 0'05, of the apical ring 002.

Habitat. — Fossil in Tertiary deposits of Greece and Sicily.

REPORT ON THE RADIOLARIA. 1569

4. Cannopilus hemisphcericus (Haeckel).

Dictyocha hemisphcerica, Ehrenberg, 1844, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 266.

Each pileated piece of the skeleton is nearly hemispherical, with thirteen meshes ; six lower
and larger meshes in the sides of the truncated six-sided pyramid, seven others in the convex surface
of the upper ring (one central with six surrounding it). From the six corners of the lower ring
arise six horizontal perradial spines. From the inside of the same ring (probably on the side of
the six ascending interradial beams) spring six centripetal teeth.

Dimensions. — Diameter of the basal ring 0'02, of the apical ring O'Ol.

Habitat. — North Atlantic ; Bermuda (Bailey).

5. Cannopilus cyrtoides, n. sp. (PI. 114, figs. 11, 12).

Dictyocha cyrtoides, Haeckel, 1881, Prodromus.

Each pileated piece of the skeleton is an eight-sided truncated pyramid, or nearly hemispherical.
From the basal ring arise twenty-four thorns or teeth, eight longer perradial centrifugal teeth
placed almost horizontally, and between these sixteen shorter adradial teeth, directed downwards
and somewhat centripetally. The network of the small hat is composed of seventeen meshes,
arranged in two rows. The eight lower meshes are hexagonal, separated by six interradial ascend-
ing beams, and twice as large as the eight upper pentagonal meshes, which are separated by eight
perradial beams, and enclose an apical central mesh.

Dimensions. — Diameter of the basal ring O04, of the apical ring 0'005.

Habitat. — Central area of the Pacific, Station 266, depth 2750 fathoms.

Family LXXIII. AUL AC A NTH ID A, Haeckel (Pis. 102-105).
Aulacanthida, Haeckel, 1862, Monogr. d. Radiol., p. 262.

Definition. — PH^EODARIA with an incomplete skeleton, composed of numerous hollow
radial tubes, which pierce the spherical calymma and touch with their proximal ends the
surface of the tripylean central capsule.

The family Aulacanthida represents a large and interesting group of PILEODAKIA,
differing from all other families of this legion in the possession of numerous large radial
tubes, which pierce the gelatinous and alveolated calymma in a radial direction, and come
in contact with the outer surface of the central capsule by their inner or proximal ends,
whilst their outer or distal ends project over the surface of the spherical calymma,
and develop a great variety of manifold branches and terminal appendages. Usually
(with the exception of a single genus only) the surface of the calymma is covered by an

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 197

1570 THE VOYAGE OF H.M.S. CHALLENGER.

arachnoidal veil or mantle, composed of thousands of very fine, hollow, tangential needles.
The skeleton therefore is incomplete, without any direct connection between the isolated
pieces, just as in the preceding Cannorrhaphida, but the latter never possess the large,
hollow, cylindrical, radial tubes, which are characteristic of all Aulacanthida.

The spherical body of the Aulacanthida has usually a diameter of 1 to 2 mm., and
including the radial tubes, of 4 to 5 mm. or more. Some species are very common and
cosmopolitan, and some genera contain numerous species, distributed widely over all oceans.
In spite of their considerable size and wide distribution, only one species of this great family
has been hitherto known, having been discovered by me at Messina in 1859, and described
in my Monograph as Aulacantha scolymantha (1862, p. 263, Taf. ii. figs. 1, 2, and
Taf. iv. figs. 1-5). I there founded for it the peculiar subfamily Aulacanthida, and
annexed it to the Thalassicollida. The same cosmopolitan species has been subsequently
observed at Messina by R. Hertwig, who first recognised the three openings in its
central capsule, and therefore united it with his TRIPYLEA (Organism, d. Racliol., 1879,
p. 88, Taf. ix. figs. 3, 4; Taf. x. figs. 7, 10). The rich collection of the Challenger has
added an astonishing number of new and interesting forms of Aulacanthida, so that I
can describe here not less than six genera and fifty-eight species. The majority are
inhabitants of the colder parts of the South Pacific and South Atlantic, at great depths,
whilst a few species only are found in the tropics.

The structure of the body in all Aulacanthida seems to be similar in all important
points, and the differences by which we are enabled to separate this great number of species
are mainly produced by differences in the development of the radial tubes, their form and
their polymorphous apophyses. The entire body represents a rather firm jelly-sphere of
1 to 2 mm. diameter (rarely less or more) ; the peripheral layer of the spherical calymma
is rather clear and transparent, whilst its central part is dark and opaque, containing the
big phseodium and the enclosed central capsule. The diameter of the latter is usually
between O'l and 0'3, often 0'4 to 0'5, or even more. The gelatinous calymma, in the centre
of which the capsule is placed, always contains numerous, large, spherical or roundish
alveoles, similar to those of Thalassicolla, and between them a delicate network of
sarcode (PI. 102, fig. 1 ; PI. 103, fig. 1 ; PL 104, fig. 1).

The spherical surface of the calymma is nearly always protected by that characteristic
arachnoidal veil or mantle, which is composed of thousands of very , fine tangential
needles, densely interwoven in all tangential directions, but never directly connected.
They are wanting in a single genus only, in Aulactinium (PI. 101, figs. 6-8). This
genus, therefore, may represent a separate subfamily, the Aulactinida, whilst all other
genera protected by that mantle constitute the subfamily Aulographida. The tangential
needles always seem to have the same shape as I have accurately described, in 1862, of
Aulacantha scolymantha. They are constantly smooth, very thin and fragile, but also very
elastic cylinders of silica, of equal breadth throughout their whole length, and seem

KEPOKT ON THE RADIOLARIA. 1571

to be open at both ends, since they are easily and constantly filled by air when dried.
Their length is usually between 0'2 and 0'3 mm., rarely less than 0'15 or more than
O'o ; their diameter is always less than O'OOl, usually less than O'OOOS.

The large radial tubes of the Aulacanthida constitute the most characteristic struc-
tures of this family, and are always so placed that their inner or proximal ends are in
loose contact with the outer surface of their central capsule (upon which they rest), whilst
their outer or distal ends are more or less prominent over the spherical surface of the
calymma. Their position, therefore, is rather loose and movable, since they are fixed
only by the consistence of the jelly of the surrounding calymma, and on the surface of
the latter by the covering veil or the mantle of tangential needles (compare PL 102,
fig. 1; PI. 103, fig. 1; PI. 104, fig. 1). Their number seems never to be fixed, and is
probably very variable in different species. I found, in 1859, in the common Aula-
cantha scolymantha, the number varying from thirty to one hundred and fifty (loc. cit.,
p. 264). So also in Aulographis pandora, Aulospathis variabilis, and some other common
species, numerous specimens of which I could compare, I found their number very variable,
being in one and the same species sometimes only from ten to twenty, at other times from
fifty to eighty, and sometimes even from one hundred to one hundred and fifty or more.
Perhaps the number increases with the age and the increasing size of the calymma.

The radial tubes are always cylindrical (circular in transverse section), never angular
or prismatic. Usually they are straight, more rarely slightly curved (PI. 105,
figs. 1, 2 ; PI. 101, fig. 6). The cylinders are usually more or less tapering towards
both ends, sometimes even spindle-shaped ; the inner or proximal end is always simple
and rounded, often slightly swollen or inflated, and ovate ; the outer or distal end is often
thickened, club-shaped, and exhibits the greatest variety in form and ramification. The
length of the radial tubes is usually from 1 to 3 mm., rarely less than 0'8, or more
than 3'2 ; their diameter is usually between 0'02 and 0'03, rarely less than O'Ol or more
than O'O 5. The smallest radial tubes are found in Aulactinium, the largest in
Aulospathis.

The siliceous wall of the cylindrical radial tubes is usually very thin, fragile, and per-
fectly structureless. Only in a few species, mainly of Avlographis, does the wall become
very thick and composed of concentric cylindrical layers (PI. 105, figs. 6—11). Their
cavity is wide and simple, and filled up by jelly (not by sarcode, as I supposed in my
first description). The simple cavity of the tubes, though not smaller than in the radial
tubes of the Aulosphserida, Circoporida and Tuscarorida, never contains the characteristic
axial filament with its branches, which is constantly found in the latter families.
According to the description of R. Hertwig, the tubes are perfectly closed and have no
opening. I suppose, however, that a small opening, always exists in the centre of the
rounded base, and perhaps a second on the distal apex. Otherwise the circum-
stance that the entire and well-preserved tubes become easily and constantly filled

1572 THE VOYAGE OF H.M.S. CHALLENGER.

up by air, when purified by hot mineral acids and afterwards dried, cannot be explained.
I suppose that the jelly contained in the cavity of the tubes remains in constant
connection by those openings with the jelly of the surrounding calymma.

The distal ends of the radial tubes exhibit in the Aulacanthida the greatest variety in
the production of different branches and capturing apparatus, and this serves for the distinc-
tion of the genera and subgenera here described. In two genera only (in Aulactinium
PI. 101, figs. 6—8 ; and in Aulacantha, PL 105, fig. 16), the distal ends are simple,
not branched. In the four other genera they are armed with terminal branches, which
are usually arranged in elegant verticils. The greatest variety in the formation of these
verticils is developed in Aulographis (PL 103). The single branches of the terminal
verticils are here simple, whilst in the closely allied Auloceras they are forked or
elegantly ramified (PL 102). Aulospathis, the biggest of all Aulacanthida, is distin-
guished by the possession of a verticil of lateral branches, placed beyond the terminal
verticil, immediately above the veil of tangential needles (PL 104). Aulodendron ,
finally, possesses lateral and terminal branches, which are irregularly scattered.

The branches of the radial tubes are rarely straight, usually more or less curved,
either simple or again ramified. Their surface is either smooth or armed with small
spines or recurved teeth, often elegantly dentated or serrated (PL 103, figs. 20—27 ;
PL 105, figs. 7—13). Their distal ends are either simply pointed or armed with a
spathilla, or a small crown of verticillate, usually recurved teeth (PL 104, figs. 4—17).
The variety and elegance of these minute armatures are very interesting, the more so as
they occur in very similar and analogous forms among the Aulosphaerida, the Ccelo-
graphida, and other PH^EODARIA.

The central capsule of the Aulasphserida and its large nucleus (" Binnenblaschen "),
as well as the surrounding alveolate calymma (" Alveolen-Hiille "), and the enclosed
dark phseodium (" dunkles Pigment") were first described in my Monograph (1862,
loc. cit., p. 362). Their minute structure has been examined afterwards very accurately
by R. Hertwig (1879, loc. cit., p. 95). The numerous well-preserved preparations of
the Challenger (stained with carmine and preserved in glycerine) which I could examine,
confirmed in all respects the detailed description of Hertwig (compare PL 102, fig. 1 ;
PL 103, fig. 1; PL 104, fig. l).

The spherical or subspherical central capsule is usually slightly depressed in the
shortened main axis. Its diameter is usually between O'l and 0 '3, rarely less than 0'0&
or more than 0'4 mm. Its outer membrane (e) is thick and double-contoured, separated
by a clear interval from the very thin but firm inner membrane (i). The large
astropyle, or the main-opening on the oral pole of the main axis, is closed by a large,
convex, radiate operculum (o), from which arises a short tubular proboscis. On both
sides of the opposite aboral pole (to the right and left) are two conical parapyla? or
secondary openings (u, u). The space between the inner membrane of the capsule and

REPORT ON THE RADIOLARIA.

1573

the nucleus is filled up by protoplasm, containing numerous spherical vacuoles of equal
size (v) ; each vacuole encloses a small, dark, fat-granule. The large nucleus (n) is
either spherical or lenticular, and more or less depressed in the main axis ; its diameter is
usually about half as great as that of the enclosing capsule, 0'05 to 0*15, rarely less or
more ; it contains, enclosed in a clear mass, numerous dark, roundish or oblongish
nucleoli (Z).

Numerous preparations of Aulacanthida exhibited a central capsule with two
nuclei (PL 101, fig. 6), or a calymma with two central capsules (PL 104, figs. 1, 3) ;
so that the process of propagation by self-division, observed already in many different
PH^EODARIA, seems to happen very frequently in the Aulacanthida. The voluminous
phseodium is usually about twice or three times as large as the central capsule, and
covers its oral or anterior half; the colour of the roundish phaeodella composing it is
sometimes more green or brown, at other times more blackish. The roundish alveoles,
which fill up the rather firm jelly of the calymma, exhibit nearly the same shape as in
the common Thallassicolla nucleata. The surface of the calymma is usually pro-
tected by the dense veil of tangential needles, and often forms conical or tent-shaped
elevations around the bases of the piercing radial tubes (PL 102, fig. l).

Synopsis of the Genera of Aulacanthida.

{Surface of the calymma naked, without tan-
gential needles, .
„,.,,.
Surface of the calymma covered by a veil of
tangential needles, ....

Radial tubes without lateral branches, j Terminal branches simple,
but with a verticil of terminal <
branches. ( Terminal branches forked or again ramified,

Radial tubes with lateral and with
terminal branches.

Lateral branches verticillate, .

Lateral branches irregularly scattered, not
verticillate, ....

665. Aulactinium.

666. Aulacantha.

667. Aulographis.

668. Auloceros.

669. Aulospathis.

670. Aulodendron.

Subfamily 1. AULACTINIDA, Haeckel.

Definition. — A ulacanthida without external veil of tangential needles on the
surface of the calymma.

Genus 665. Aulactinium,1 n. gen.

Definition. — A ulacanthida without a veil of tangential needles, with simple
radial tubes, which bear neither lateral nor terminal branches.

1 Aulactinium = ~W iih radial tubes ; «£%«;, &XT/;.

1574 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Aulactinium differs from all the other Aulacanthida in the complete
absence of the characteristic fine tangential needles, which constitute in the latter an
arachnoidal veil or mantle around the spherical calymma. We accordingly divide
the whole family into two subfamilies, the Aulactinida with a naked calymma, and the
Aulagraphida with a veil of tangential needles. The radial tubes possess in the
few species of Aulactinium observed a very simple shape, as in the closely allied
Aulacantha.

1. Aulactinium, actinastrum, n. sp. (PI. 101, figs. 6, 7).

Eadial tubes slenderly spindle-shaped, slightly curved, gradually tapering from the middle towards
both ends. The proximal two-thirds of the tubes enclosed in the calymma are smooth ; the distal
freely prominent third is armed with six to eight equidistant verticils of small conical teeth (ten to
fifteen in each verticil).

Dimensions. — Length of the tubes 0'5 to 1'5, breadth 0'02.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

2. Aulactinium actinelium, n. sp. (PI. 101, fig. 8).

Eadial tubes cylindrical, straight, slightly tapering towards both ends. Proximal two-thirds
smooth, the distal third studded with numerous small recurved thorns.
Dimensions. — Length of the tubes 0'6 to 0'9, breadth 0'02.
Habitat. — South Pacific, Station 293, depth 2025 fathoms.

3. Aulactinium actinosphcerium, n. sp.

Eadial tubes cylindrical, straight, smooth, of nearly equal breadth throughout their whole length,
without thorns and spathillse, pointed at both ends.

Dimensions. — Length of the tubes 1'6 to 2'2, breadth 0'02 to 0'03.
Habitat. — Antarctic Sea, Station 157, depth 1950 fathoms.

Subfamily 2. AULOGRAPHIDA, Haeckel.

Definition. — A ulacanthida with an external veil of interwoven, very numerous
and thin, hollow, tangential needles, entirely covering the surface of the calymma.

Genus 666. Aulacantha,1 Haeckel, 1860, Monatsber. d. k. preuss. Akad. d.

Wiss. Berlin, p. 799.

Definition. — A ulacanthida with a veil of tangential needles, and with simple
radial tubes, which bear neither lateral nor terminal branches.

1 Aulacantha^ Tubular spine ; dvKos, <Stx»u6».

REPORT ON THE RADIOLARIA. 1575

The genus Aulacantha, hitherto the only representative of this family, was founded
by me in 1860 for the cosmopolitan Aulacantha scolymantha, the most common
and most widely distributed of all the members of the family. It is the simplest
form of the Aulographida, or of those Aulacanthida in which the spherical surface of the
calymma is densely covered with interwoven tangential needles. The large radial tubes
of Aulacantha possess a very simple shape, as in the preceding Aulactinium, and have
neither lateral nor terminal branches.

1. Aulacantha scolymantha, Haeckel.

Aulacantha scolymantha, Haeckel, 1862, Monogr. d. Radiul., p. 263, Taf. ii. figs. 1, 2, Taf. iv.

figs. 1-5.
Aulacantha scolymantha, R. Hertwig, 1879, Organism, d. Radiol., p. 88, Taf. ix. fig. 3, Taf.

x. figs. 7-10.

Radial tubes cylindrical, straight, of nearly equal breadth throughout their whole length, some-
what inflated on the proximal basal end, smooth throughout the greater part of their length, but
in the distal third dentate, with numerous (ten to forty) small pointed teeth, which are curved
outwards, and shorter than the thickness of the tube.

Dimensions. — Length of the tubes 0'5 to 2'0, breadth O'Ol to 0'02.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific ; at many Stations ; surface
and at various depths ; the most common of all Aulacanthida.

2. Aulacantha tubulosa, n. sp.

Eadial tubes cylindrical or nearly spindle-shaped, straight, gradually tapering towards the two
pointed ends, twice as broad in the middle third as in the outer and inner third, smooth in the
inner half, dentate in the outer half, with very numerous (one hundred to two hundred) short conical
teeth, which are scarcely one-fourth as large as the greatest breadth of the tube.

Dimensions. — Length of the tubes 0'4 to 0'5, breadth in the middle part 0'02 to 0'03.

Habitat. — Central Pacific, Stations 271 to 274, surface.

3. Aulacantha spinosa, n. sp. (PI. 105, fig. 4).

Eadial tubes cylindrical, straight, of equal breadth throughout their whole length, rounded on
the proximal base, smooth in the inner proximal half, dentate or spinescent in the outer distal half,
with numerous (fifty to eighty) slender conical teeth, which are curved forwards, increasing in size
towards the distal end, and somewhat longer than the breadth of the tube.

Dimensions. — Length of the tubes 0'8 to T2, breadth 0'015 to 0'02.

Habitat. — North Pacific, Stations 241 to 253, surface.

1576 THE VOYAGE OF H.M.S. CHALLENGER.

4. Aulacantha cannulata, n. sp. (PI. 105, fig. 16).

Radial tubes cylindrical in the inner proximal half, prismatic in the outer distal half, with
from three to six, usually four, prominent, thick, parallel edges, which are dentate towards the thicker
distal end ; their teeth short, conical, directed outwards, scarcely one-fourth as long as the thickness
of the tube. The edges are separated in the distal third by more or less deep furrows, like a
channelled column.

Dimensions. — Length of the tubes T2 to 2'5, breadth 0-03 to 0'04.

Habitat. — South Pacific, Stations 291 to 293, surface.

5. Aulacantha clavata, n. sp.

Radial tubes more or less irregularly curved, in the inner proximal half slenderly conical, and
gradually tapering towards the inflated base, in the outer distal half club-shaped, armed with a few
(five to twenty) short conical teeth.

Dimensions. — Length of the tubes I/O to 1'2, breadth in the middle part O'Ol, in the distal part
0-04.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

6. Aulacantha Icevissima, n. sp.

Radial tubes cylindrical, straight, of nearly equal breadth throughout their whole length ; the
inner proximal end rounded, the outer distal end pointed. Surface of the tubes perfectly smooth,
without any teeth. The thickness and length of the simple spicula, as well as the thickness of
their wall, are very variable in this species.

Dimensions. — Length of the tubes 0'5 to 4'2, breadth 0'003 to OD2.

Habitat. — North Atlantic, Station 253, Fseroe Channel, surface, John Murray.

Genus 667. Aulogra^this,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena,

Dec. 12, p. 5.

Definition. — A ulacanthida with a veil of tangential needles, and with radial
tubes, which bear no lateral branches, but at the distal end a verticil of simple terminal
branches.

The genus Aulographis, the richest in the number of species among all Aulacanthida,
differs from the preceding Aulacantha, its ancestral form, in the development of simple
terminal branches, which form either a fork or a verticil. The branches are either
smooth or spiny, but not ramified as in the following genus, Auloceros. Their distal

1 Aulographia='T\\\m\a.T style;

REPORT ON THE RADIOLARIA. 1577

ends are either simply pointed or bear a terminal spathilla, or a little crown of

recurved teeth. According to these differences we may dispose the twenty-six
species described into four subgenera.

Subgenus 1. Aulographantha, Haeckel.

Definition. — Terminal branches of the radial tubes simple, smooth, without lateral
teeth and terminal spathillse. Tubes usually thin and fragile.

1. Aulographis pandora, n. sp. (PL 103, figs. 2-9).

Eadial tubes cylindrical, slender, straight or slightly curved, of equal breadth. Terminal
branches of the tubes very variable in size and number (two to six, usually three or four), without
lateral teeth and terminal spathilla?, slender, conical, slightly curved, directed outwards, twice to four
times (rarely five to eight times) as long as the breadth of the tubes. This species is extraordinarily
variable in the number and size of the simple terminal branches ; the eight tubes shown in fi^s.

j. ' O * O

2 to 9, are all found in one and the same specimen.

Dimensions. — Length of the tubes 0'5 to 1'5, breadth O'Ol to 0'03 ; branches O02 to 012.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific ; surface and in various
depths.

2. Aulographis bovicornis, n. sp. (PI. 103, figs. 12—14).

Eadial tubes cylindrical, slender, straight, of equal breadth. Terminal branches usually two
(rarely three), smooth, without lateral teeth and terminal spathilla?, eight to ten times as long as
the breadth of the tube, pointed, S-shaped, or curved like the horns of an ox.

Dimensions. — Length of the tubes 0-6 to 0'8, breadth 0'015 to 0'02 ; branches 01 to 0'2.

Habitat. — South Atlantic (east of Buenos Ayres), Stations 323 to 325, surface.

3. Aulographis taumorpha, n. sp. (PI. 103, fig. 16).

Eadial tubes cylindrical, slender, straight, gradually tapering towards the pointed proximal end.
Terminal branches constantly two, opposite in a tangential, slightly concave or nearly straight line,
ten to twelve times as long as the breadth of the tube, smooth, straight in the proximal part,
recurved in the distal part.

Dimensions. — Length of the tubes 0'7 to 0'8, breadth O'Ol to O'Olo; branches 01 to 015.

Habitat. — North Pacific, Station 231, depth 2250 fathoms.

(ZOOL. CHALL. KXP. — PART XL. — 1886.) Rr 198

1578 THE VOYAGE OF H.M.S. CHALLENGER.

4. Aulographis triglochin, n. sp. (PL 103, fig. 17.).

Eadial tubes robust, club-shaped at the distal end. Terminal branches three (rarely two or
four), widely divergent, geniculated and recurved, smooth, without lateral teeth and terminal
spathillse.

Dimensions. — Length of the tubes T2 to 1'8, breadth 0-02 ; branches 012 to 015.

Habitat. — Central Pacific, Stations 27 1 to 274, surface.

5. Aulographis cruciata, n. sp. (PI. 103, fig. 25).

Eadial tubes slender, cylindrical, of equal breadth. Terminal branches almost constantly four,
equal, regularly crossed (very rarely three or five), slender, straight or slightly curved, smooth,
divergent outwards, six to eight times as long as the breadth of the tube.

Dimensions. — Length of the tubes TO to 1'5, breadth 0'02 ; branches 0'12 to 015.

Habitat. — South Atlantic, Stations 325 to 332, surface.

6. Aulographis ancorata, n. sp. (PL 103, fig. 21).

Eadial tubes slender, cylindrical, straight. Terminal branches constantly four, equal, regularly
crossed, arcuato-recurved or nearly semicircular, smooth, six to eight times as long as the breadth
of the tube. Eesembling an anchor with four teeth.

Dimensions. — Length of the tubes 0'5 to 0'7, breadth 0'012 to 0'015 ; branches 0'07 to 0'09.

Habitat. — South-west Atlantic, Station 318, depth 2040 fathoms.

7. Aulographis stellata, n. sp. (PL 103, figs. 23, a— c).

Eadial tubes club-shaped, gradually thickened towards the distal end. Terminal branches
stellate, numerous (five to ten or more), diverging in all directions, smooth, straight or slightly
curved, slenderly conical, three to five times as long as the distal breadth of the tube. The
branches are very variable in size, sometimes very small (figs, a, b).

Dimensions. — Length of the tubes 0'4 to 0'8, breadth 0'02 ; branches O'Ol to 0'02.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

8. Aulographis penicillata, n. sp.

Eadial tubes slender, cylindrical, of equal breadth. Terminal branches pencil-shaped, smooth,
very numerous (twenty to thirty or more), diverging outwards, curved, eight to ten times as' long as
the breadth of the tube, very thin and fragile, resembling a brush.

Dimensions. — Length of the tubes TO to 1'5, breadth 0'02 ; branches 015 to 0'2.

Habitat. — North Atlantic (Antilles), Weber, surface.

REPORT ON THE RADIOLARIA. 1579

9. Aulographis pistillum, n. sp. (PI. 105, fig. 6).

Eadial tubes club-shaped, robust, straight, gradually thickened towards the distal end. Terminal
branches eight to ten (usually nine), conical, smooth, slightly curved, divergent outwards like a
regular corona.

Dimensions. — Length of the tubes 0'5 to 0'6, distal breadth 0'04 ; branches 0'08.

Habitat. — North Atlantic, Station 354, depth 1675 fathoms.

Subgenus 2. Aulographella, Haeckel.

Definition. — Terminal branches of the radial tubes without terminal spathillse, but
with lateral teeth or secondary spines. (Tubes usually very stout and robust, club-
shaped.)

10. Aulographis tricena, n. sp. (PI. 105, fig. 8).

Eadial tubes club-shaped, straight, tapering gradually towards the rounded proximal end.
Terminal branches constantly three, divergent, very stout, eight to ten times as long as the breadth
of the tube, each studded with three to six irregular, conical, secondary spines. Sometimes the
branches become forked, the species passing over into Auloceros cervinus.

Dimensions. — Length of the tubes 1'2 to T5, breadth 0'004 to 0'06 ; branches 0'3 to 0'5.

Habitat. — South Pacific, Station 299, depth 2160 fathoms.

11. Aulographis martagon, n. sp. (PI. 105, fig. 7).

Eadial tubes club-shaped or slenderly conical, strongly thickened towards the distal end.
Terminal branches six to nine, conical, slightly curved, divergent outwards, studded outside with
small, conical, secondary spines, twice to three times as long as the breadth of the tube.

Dimensions. — Length of the tubes I'O to 1*2, breadth 0'04 to 0'05; branches 01 to 015.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

12. Aulographis flammabunda, n. sp. (PL 105, fig. 9).

Eadial tubes club-shaped, more or less curved, with thickened distal ends. Terminal branches
three to six, conical, very stout, three to four times as long as the breadth of the tube, densely
studded with numerous, crowded, conical, secondary spines, which are very irregular and more or less
curved, resembling the flames of a fire.

Dimensions. — Length of the tubes I'O to 1'2, distal breadth 0'08 to 01; branches 0'2 to 0-4.

Habitat. — South Pacific, Station 302, depth 1450 fathoms.

1580 THE VOYAGE OF H.M.S. CHALLENGER.

13. Aulographis gemmascens, n. sp. (PL 105, fig. 11).

Radial tubes club-shaped, more or less curved, with thickened distal end. Terminal branches
three to nine (usually three larger and six smaller) stout, conical, studded with irregular, straight,
conical, secondary spines, crowded and densely aggregated, like the leaves in a bud.

Dimensions. — Length of the spines T5 to 1'8, distal breadth O07 to 01; branches 0'2 to O6.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

14. Aulographis flosculus, n. sp. (PI. 105, fig. 10).

Radial tubes club-shaped, straight, tapering gradually towards the rounded proximal end.
Terminal branches nine to twelve, stout, conical, twice to three times as long as the breadth of the
tube, studded with irregular secondary spines, connected in the proximal half by a solid, cap-shaped,
flinty lamella, so that the terminal corona resembles a flower. The hollow canal of the tube sends
a thin branch into each branch of the crown.

Dimensions. — Length of the tubes 1'2 to 1*8, distal breadth 0'04 to O'Oo ; branches 01 to 0'2.

Habitat. — North Atlantic, Faroe Channel (Gulf Stream), John Murray, depth 600 fathoms.

Subgenus 3. Aulographidium, Haeckel.

Definition. — Terminal branches of the radial tubes armed with terminal spathillse
(or whorls of small radial teeth), but without lateral denticles or spines.

15. Aulographis furcula, n. sp. (PI. 103, figs. 10, 11).

Radial tubes cylindrical, slender, slightly curved. Terminal branches usually two, sometimes on
single tubes three, eight to ten times as long as the tube is broad, strongly curved, ascending
vertically from a horizontal base, with a terminal spathilla of four crossed teeth at the distal end.

Dimensions. — Length of the tubes 0'6 to 0'8, breadth O'OOG to O'OOS ; branches 0'06 to O'OS.

Habitat. — North-west Pacific (off Japan), Station 231, depth 2250 fathoms.

16. Aulographis triangulum, n. sp. (PI. 103, fig. 15).

Radial tubes cylindrical, slender, straight. Terminal branches constantly three, slender, slightly
curved, nearly horizontally (tangentially) expanded, eight to ten times as long as the tube is broad,
with a terminal spathilla of four recurved teeth which are opposite in pairs. Since the angles
between the three branches are equal ( = 120°) they correspond to the axes of an equilateral
triangle.

Dimensions. — Length of the tubes 1'2, breadth 0'015 to 0'02 ; branches 01 to 012.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

REPORT ON THE RADIOLARIA. 1581

17. Aulographis tetrancistra, n. sp. (PI. 103, fig. 22).

Eadial tubes slender, cylindrical, straight. Terminal branches four to six (usually four), eight
to ten times as long as the tube is broad, slightly curved and widely divergent, with a terminal
spathilla of four crossed recurved teeth.

Dimensions. — Length of the tubes 0'5 to 0'7, breadth O'Ol ; branches 0'08 to 01.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

18. Aulographis hexancistra, n. sp. (PL 103, figs. 18, 19).

Eadial tubes club-shaped, slightly curved, gradually thickened from the proximal to the distal
end. Terminal branches four to eight (usually six in the majority of tubes), widely divergent,
nearly straight, three to four times as long as the tube is broad, with a terminal spathilla of six
(rarely five) recurved teeth.

Dimensions.— Length of the tubes 0'4 to 0'6, breadth O'Ol to 0'02 ; branches 004 to 0'08.

Habitat. — North Pacific, Stations 244 to 253, depth 2050 to 3125 fathoms.

19. Aulographis polyancistra, n. sp.

Eadial tubes club-shaped, straight, thickened towards the distal end. Terminal branches ten
to twenty, smooth, strongly curved, disposed in a corona, six to eight times as long as the tube is
broad, each with a terminal spathilla of eight to twelve radial teeth.

Dimensions. — Length of the tubes 0'6 to 0'8, distal breadth 0'02 ; branches 012 to 016.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

20. Aulographis asteriscus, n. sp. (PL 103, fig. 24).

Eadial tubes slender, cylindrical, straight, equally broad. Terminal branches six to nine, widely
divergent, disposed in a radiate corona around a central branch, which is the distal prolongation of
the tube itself. Each branch bears a stellate terminal spathilla, composed of ten to twenty conical
teeth, which radiate in all directions.

Dimensions. — Length of the tubes 0-5 to 0'8, breadth 0'02 ; branches 0'06 to 0'09.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

Subgenus 4. Aulographonium, Haeckel.

Definition. — Terminal branches of the radial tubes armed with numerous lateral
denticles, and with terminal spathillse (or whorls of small radial teeth).

1582 THE VOYAGE OF H.M.S. CHALLENGER.

21. Aulographis dentata, n. sp. (PI. 103, fig. 20).

Radial tubes slender, cylindrical, equally broad, scarcely inflated at the distal end. Termina
branches six to eight, curved, disposed in a corona around a straight central branch, eight to ten
times as long as the tube is broad, armed with numerous stout recurved lateral denticles and with
a terminal spathilla of five or six recurved teeth.

Dimensions. — Length of the tubes T5 to 2'5, breadth 0'03 ; branches 015 to 02 long.

Habitat. — North Atlantic, Station 354, depth 1675 fathoms.

22. Aulographis pulvinata, n. sp. (PI. 103, fig. 26).

Radial tubes club-shaped, straight, gradually thickened towards the distal end, which bears a
broad, circular, biconvex cushion. The margin of this cushion bears two alternating verticils of
radially divergent, straight, terminal branches, which are twice to three times as long as the tube is
broad. Each branch is armed with two opposite lateral rows of numerous small denticles, and
bears a terminal spathilla with six to eight recurved radial teeth.

Dimensions. — Length of the tubes 2'0 to 24, distal breadth 0'03 to 0-07; branches O05 to 0'08 long.

Habitat. — South-east Pacific (off Valparaiso), Station 298, depth 2225 fathoms.

23. Aulographis tripentas, n. sp. (PI. 105, fig. 13, 13a).

Radial tubes club-shaped, straight, thickened towards the inflated distal end, which bears three
alternating verticils of terminal branches, each with five radial branches. The ten branches of the
inner and outer verticils are perradial, smooth ; the alternating five branches of the middle verticil
are armed with recurved lateral denticles. Each of the fifteen branches bears a terminal spathilla
with five to seven recurved teeth.

Dimensions. — Length of the spines 2'0 to 2'5, distal breadth 0'03 to 0'06 ; branches 01 long.

Habitat. — South-east Pacific (off Juan Fernandez), Station 299, depth 2160 fathoms.

24. . Aulographis verticillata, n. sp. (PI. 105, fig. 12, 12a).

Radial tubes cylindrical, equally broad, with an inflated ellipsoidal knob at the distal end. This
knob bears twenty to thirty slender, slightly curved, terminal branches, which are regularly arranged
in five radial or meridional rows, and in four to six concentric verticils. The branches are five to
ten times as long as the tube is broad, and armed with two opposite rows of lateral denticles, and
with a terminal spathilla of six to eight recurved teeth.

Dimensions. — Length of the tubes 1'5 to T8, breadth O'Ol to 0'02; branches 0'5 to TO long.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

25. Aulographis serrulata, n. sp. (PI. 103, fig. 27).

Radial tubes club-shaped, curved, thickened towards the inflated ellipsoidal distal end, which
bears a bunch of fifteen to twenty-five terminal branches, arranged more or less regularly in radial

REPORT ON THE RADIOLARIA. 1583

or meridional rows and concentric horizontal verticils. The branches are irregularly curved, twice to
four times as long as the distal end of the tube, armed with two opposite rows of lateral denticles,
and at the distal end with a spathilla of six radial teeth.

Dimensions. — Length of the tubes 1'5 to 1'8, breadth 0'02 to 0'04; branches O'l to 0'15 long.

Habitat. — North Pacific, Stations 253 and 254, depth 3025 to 3125 fathoms.

26. Aulographis candelabrum, n. sp. (PI. 103, fig. 1).

Radial tubes club-shaped, straight, thickened towards the distal end and constricted beyond the
ovate, inflated, terminal knob. This knob is similar to a candelabrum and bears a corona of six to
nine strongly curved terminal branches, which are eight to ten times as long as the tube is broad,
armed with scattered lateral denticles, and with a spathilla of five to seven radial teeth.

Dimensions. — Length of the tubes 1/6 to 2'4, breadth 0'03 to 0'05 ; branches 0'2 to 0'3 long.

Habitat. — South-east Pacific (off Juan Fernandez), Station 300, depth 1375 fathoms.

Genus 668. Auloceros,1 n. gen.

Definition. — A ulacanthida with a veil of tangential needles, and with radial
tubes, which bear no lateral branches, but at the distal end a verticil of ramified or
forked terminal branches.

The genus Auloceros differs from the preceding closely allied Aulographis, its
ancestral form, in the ramification of the verticillate terminal branches. They are
either simply forked or again ramified, and their distal ends are either simply pointed
or armed with a terminal spathilla, or a little crown of recurved teeth. Some forms of
this genus belong to the most elegant and graceful PH^ODARIA, as the Auloceros elegans
figured, which 1 observed living in the Indian Ocean.

Subgenus 1. Aulocercea, Haeckel.

Definition. — Distal ends of the terminal branches pointed, smooth, without spathilla
(or corona of radiate denticles).

1. Auloceros fur cosus, n. sp: (PI. 102, figs. 2—6).

Radial tubes slender, spindle-shaped or nearly cylindrical, more or less tapering towards the
two ends. Terminal branches slender, curved, twice to four times as long as the tube is broad,
very variable in number (usually two or three, rarely four, five, or six ; compare figs. 2-6), once
or twice forked; the secondary branches are short, irregular, and. pointed. No terminal spathillae.

1 Auloceros = Tubular horn ; aiXo'f, xi^af.

1584 THE VOYAGE OF H.M.S. CHALLENGER.

In some specimens of this species all the tubes bear two or three terminal branches, whilst in
others there are tubes with four, five, or six branches intermingled. When the number of the
terminal branches is constant in single localities, this transformistic or " Darwinian " species may
be divided into the following "subspecies:" (1) Auloceros pandora (with variable numbers); (2)
Auloceros bifurca (fig. 2) ; (3) Auloceros trifurca (fig. 3) ; (4) Auloceros quadrifurca (fig. 4) ; (5)
Auloceros quinquefurca (fig. 5) ; (6) Auloceros sexfurca (fig. 6).

Dimensions. — Length of the tubes To to 2'5, breadth 0'02 to 0'03 ; branches O'Oo to 015 long.

Habitat. — North Pacific, Stations 231 to 253, surface and at various depths.

2. Auloceros trigemimts, n. sp. (PI. 102, fig. 7).

Eadial tubes club-shaped, gradually thickened towards the inflated distal end. Terminal
branches short, scarcely longer than the tube is broad, two constantly opposite, each with three
equal, conical, short secondary branches. No terminal spathillae.

Dimensions. — Length of the tubes O6 to 0'8, breadth 0'02 to 0'03 ; branches 0'04 to 0'08.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

3. Auloceros capreolus, n. sp. (PI. 102, fig. 8).

Eadial tubes cylindrical, equally broad. Terminal branches in two opposite clustered bunches,
each with sixteen to eighteen unequal secondary branches. The total length and breadth of each
cluster is about four times as great as the tube is broad. No terminal spathillas.

Dimensions. — Length of the tube 1'5 to 2'0, breadth 0'03 ; branches 0'07 to O'l.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

4. Auloceros cervinus, n. sp. (PI. 102, figs. 9, 10).

Eadial tubes slender, spindle-shaped, slightly curved, tapering gradually from the middle
towards the two ends. Terminal branches constantly three, obliquely ascending, each twice or three
times forked (often more or less irregularly), with slender, curved, secondary and tertiary branches
(twenty to twenty-four on each tube) ; the latter are scarcely half as broad as the three main
branches of each tube. No terminal spathillae.

Dimensions. — Length of the tubes 2-0 to 3'5, breadth 0'03 to 0'04; branches 012 to 015 long.

Habitat. — South Atlantic, Station 325, depth 2650 fathoms.

5. Auloceros elegans, n. sp. (PL 102, fig. 1).

Eadial tubes slender, cylindrical, straight, equally broad. Terminal branches two or three,
more or less irregularly branched, each with twelve to eighteen curved and pointed secondary
branches. No terminal spathillae. Differs from the preceding Auloceros cervinus in the cylindrical
form of the thinner straight tubes, and the more irregular ramification ; the branches are nearly

REPORT ON THE RADIOLARIA. 1585

tangentially expanded. The specimen figured, with expanded pseudopodia, red central capsule, and
green phteodium, was observed living by me in 1882 in Ceylon.

Dimensions. — Length of the tubes 1-0 to 2'0, breadth 0'02 to 0'03 ; branches 0'15 to 0'3.

Habitat. — Indian Ocean, Ceylon (south of Matura), Haeckel, surface.

Subgenus 2. Auloceratium, Haeckel.

Definition. — Distal ends of the terminal branches with a spathilla, or a small corona
of radial, usually recurved teeth.

6. Auloceros dicranaster, n. sp. (PI. 105, figs. 14, 15).

Eadial tubes cylindrical, straight, equally broad. Terminal branches tangential, forked, expanded
horizontally, five to six times as long as the tube is broad ; their number is usually five (more
rarely four or six), and each is divided into two short, equal, divergent, secondary branches, armed
at the distal end with a spathilla of five or six unequal recurved teeth.

Dimensions. — Length of the tubes TO to 1'5, breadth O'Ol to 0'02 ; branches O'Oo to O'OS.

Habitat. — Xorth Pacific, Stations 244 to 252, depth 2050 to 3050 fathoms.

7. Auloceros spathillastcr, n. sp. (PI. 102, fig. 12).

Eadial tubes club-shaped or nearly cylindrical, straight, often thickened towards the distal end.
Terminal branches ascending, three to six, usually four, partly simple, partly forked, slightly curved.
The branches are from twice to three times as long as the tube is broad, and much thinner ; at the
distal end they are armed with a spathilla of five or six recurved teeth.

Dimensions. — Length of the tubes 2'0 to 2'5, breadth 0'02 to 0'03 ; branches 0'08 to 012.

Habitat. — South Atlantic, Station 319, depth 2425 fathoms.

8. Auloceros arborescens, n. sp. (PI. 102, figs. 11, 13).

Eadial tubes club-shaped, irregularly curved, thickened towards the distal end. Terminal
branches two opposite (rarely three or four), forked near the base, and either dichotomously or
more irregularly branched ; each tube bears fifteen to thirty, usually twenty to twenty-four,
secondary branches, which are irregularly curved, and armed at the distal end with a spathilla
of four to eight recurved teeth. The tubes are more richly branched than in the preceding,
smaller, closely allied species, and the branches are more flatly expanded.

Dimensions. — Length of the tubes 2'6 to 3'3, breadth 0'03 to 0'04 ; branches O'l to 0'2.

Habitat. — South Pacific, Stations 288 to 295, depth 1500 to 3000 fathoms.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 199

1586 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 669. Aulospathis,1 n. gen.

Definition. — A ulacanthida with a veil of tangential needles, and with radial
tubes, which bear two verticils of branches, a distal verticil of terminal branches, and a
proximal verticil of lateral branches.

The genus Aulospathis and the following Aulodendron differ from the preceding
Aulacanthida in the possession of lateral branches ; these are usually similar to the
terminal branches, and irregularly scattered along the distal half of the tubes in
Aulodendron. In Aulospathis, however, the largest form in the family, each tube bears
two whorls or verticils only, a verticil of terminal branches at the distal end, and a
verticil of lateral branches beyond the latter, between the middle and distal third of
the tube. The number of branches in each verticil is usually from two to four, rarely
more ; it is, however, very variable, so that the ten species described in the sequel are
"Darwinian species," derived either from Aulospathis polymorpha or from Aulospathis '
variabilis. Each branch bears at the distal end a spathilla, the teeth of which are very
variable in form, number and arrangement.

Subgenus 1. Aulospathessa, Haeckel.

Definition. — Distal ends of the radial tubes inflated, usually in the form of an ovate
or pyriform terminal knob.

1. Aulospathis bifurca, n. sp. (PI. 104, figs. 1-5).

Eadial tubes with an inflated ovate terminal knob at the distal end, which bears two divergent,
curved, terminal branches (often a few tubes bear three or four branches instead of the usual two).
Proximal whorl usually cruciate, with four irregularly crossed lateral branches (but often with five
or six, more rarely with two or three).

Dimensions. — Length of the tubes 015 to 25 mm., breadth 0'04 to 0'06 ; branches O'l to 015.

Habitat. — South Pacific, Stations 293 to 295, depth 1500 to 2270 fathoms.

2. Aulospathis trifurca, n. sp. (PL 104, figs. 6, 7, 7 a).

Pvadial tubes with an inflated ovate terminal knob at the distal end, which bears three divergent,
straight, or slightly curved terminal branches (often a few tubes bear two or four branches instead
of the usual three). Proximal whorl irregular, usually with six divergent, straight, lateral branches.

Dimensions. — Length of the tubes 2'2 to 3'4, breadth 0'03 to 0'05 ; branches 01 to 015.

Habitat. — South Pacific (off Valparaiso), Stations 298 to 300, depth 1375 to 2225 fathoms.

1 Aulospathis=Tn\3e with whirls ; ctvhos,

REPORT ON THE RADIOLARIA. 1587

3. Aulospathis quadrifurca, n. sp.

Eadial tubes with an inflated ovate terminal knob at the distal end, which bears four crossed,
divergent, curved terminal branches. Proximal whorl also rather regular, with a cross of four
straight lateral branches.

Dimensions. — Length of the tubes 3'0 to 4'0, breadth O04 to 0'08 ; branches 0'2 to 0'3.

Habitat. — South Pacific, Station 291, depth 2250 fathoms.

4. Aulospathis poly morpha, n. sp. (PL 104, figs. 10-13).

Eadial tubes with an inflated ovate terminal knob at the distal end, which bears a variable
number of divergent, curved, irregular, terminal branches. Usually the majority of the tubes bear
three branches, whilst others exhibit two or four, sometimes also five or six. Proximal whorl also
very variable and irregular, with two to six, usually three or four unequal branches.

Dimensions. — Length of the tubes 2'0 to 4'0, breadth 0'04 to 0'06 ; branches 01 to 0'3.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

Subgenus 2. Aulospathilla, Haeckel.

Definition. — Distal ends of the radial tubes of equal breadth or tapering gradually,
not inflated, without terminal knobs.

5. Aulospathis diodon, n. sp.

Eadial tubes without inflated terminal knob, forked at the tapering distal end, with two divergent
curved branches of equal size. Proximal whorl cruciate, with four rather equal, crossed, straight,
lateral branches (sometimes three or five instead of four in single tubes).

Dimensions. — Length of the tubes 2'0 to 2'5, breadth 0'03 to 0'04 ; branches 01 to 0'3.

Habitat. — North Pacific, Station 231, depth 2250 fathoms.

6. Aulospathis triodon, n. sp. (PL 104, fig. 8).

Eadial tubes without inflated terminal knob, with three divergent, slightly curved, terminal
branches. Proximal whorl with a variable number of curved lateral branches, usually also three
(often two or four, rarely more).

Dimensions — Length of the tubes 2 to 3, breadth 0'03 to 0'05 ; branches 0'2 to 0-3.

Habitat. — North Pacific, Stations 250 to 253, depth 2740 to 3125 fathoms.

1588 THE VOYAGE OF H.M.S. CHALLENGER.

7. Aulospathis tetrodon, n. sp. (PI. 104, fig. 9).

Eadial tubes without inflated terminal knob, with four crossed, divergent, slightly curved terminal
branches. Proximal whorl usually with an irregular cross of four lateral branches (often five or
six, rarely two or three instead of the usual four).

Dimensions. — Length of the tubes 2'0 to 2'5, breadth 0'03 to 0'04 ; branches 0'2 to 0'3.

Habitat. — North Pacific, Stations 244 to 245, depth 2775 to 2900 fathoms.

8. Aulospathis hexodon, n. sp.

Eadial tubes without inflated terminal kuob, with three forked, curved branches at the distal
end, so that each tube usually bears six terminal branches ; but other tubes of the same specimen
bear only three simple or a few irregularly forked branches. Proximal whorl usually with six
curved, irregular, lateral branches.

Dimensions. — Length of the tubes 2'0 to 3'0, breadth 0'03 to 0'06 ; branches 0'2 to 0'5.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

9. Aulospathis fur 'cata, n. sp.

Eadial tubes without inflated terminal knob, with a variable number of unequal terminal
branches, which are partly simple, partly irregularly forked or branched; the usual number
of terminal branches is three or four, more rarely two or five or six. Proximal whorl very irregular,
usually with four to six unequal, lateral branches.

Dimensions. — Length of the tubes 2'0 to 2'5, breadth 0'03 to 0'05 ; branches 01 to 0'3.

Habitat. — Stations 265 to 268, depth 2700 to 2900 fathoms.

10. Aulospathis variabilis, n. sp. (PI. 104, figs. 14-17).

Eadial tubes without inflated terminal knob, with a variable number of unequal terminal
branches, which are constantly simple, never forked ; the usual number is in the majority of the
tubes three or four, often also two, rarely five to eight. Proximal whorl irregular, with a variable
number of lateral branches (usually four to six).

Dimensions. — Length of the tubes 2'0 to 3'0, breadth 0'03 to 0'06 ; branches 01 to 0'3:
Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

Genus 670. Aulodendron,1 n. gen.

Definition. — Aul a canthida with a veil of tangential needles, and with radial
tubes, which bear numerous, irregularly scattered, lateral and terminal branches.

1 Aitlodendron = Tubular tree ;

REPORT ON THE RADIOLARIA. 1589

The genus Aulodendron differs from the other Aulacanthida in the possession of
lateral and terminal branches, which are irregularly scattered on the radial tubes and
not arranged in regular verticils. The branches are usually short, simple or forked,
rarely longer and again irregularly ramified.

1. Aulodendron antarcticum, n. sp. (PI. 105, fig. 5).

Eadial tubes cylindrical, more or less curved, in the inner proximal half smooth and half as
broad as in the outer distal half, which is studded with irregularly curved, partly branched spines,
arising usually perpendicularly from the tube. The majority of the spines usually simple, the
minority forked, with two to four short branches, the largest spines scarcely twice as long as the
breadth of the tube.

Dimensions. — Length of the tubes 0'7 to 0'9, breadth O'Ol to 0'02 ; length of the branches
0-02 to 0-04.

Habitat. — Antarctic Ocean (Kerguelen), Stations 156 to 159, surface.

2. Aulodendron paclficum, n. sp. (PI. 105, fig. 2).

Eadial tubes cylindrical, slightly curved, in the proximal half smooth, in the distal half with
scattered lateral branches, which are partly simple, partly forked, about twice as long as the
breadth of the tube, and bear at the distal end a spathilla with five to six recurved teeth. The
distal end of the tubes bears a spherical knob, which is separated by a deep stricture and armed
with a bunch of six to twelve strong conical teeth.

Dimensions. — Length of the tubes 1 to T2, breadth 0'015 to 0'02 ; branches 0'03 to 0'04.

Habitat. — Soutli Pacific, Station 293, depth 2025 fathoms.

3. Aulodendron australe, n. sp. (PI. 105, fig. 3).

Eadial tubes cylindrical, straight, thin, smooth in the proximal half, armed with numerous
lateral branches in the distal half; the majority of the branches forked, about as long as the
breadth of the tube, with two or three short ramules, each of which bears a spinulate terminal
knob. The distal end of the tubes also forked, with two or three divergent branches.

Dimensions. — Length of the tubes 1'2 to 1'6, breadth O'Ol to 0'012.

Habitat. — South Pacific, Station 289 ; New Zealand, Station 169, surface.

4. Aulodendron atlanticum, n. sp.

Eadial tubes cylindrical, tapering gradually towards the two ends ; smooth and straight in the
proximal half, irregularly curved and branched in the distal half, with ten to twenty (rarely more)
branches, which arise almost perpendicularly from the tube. The proximal branches are from four
to eight times as long as the greatest breadth of the tube, forked, with two or three short ramules ;

1590 THE VOYAGE OF H.M.S. CHALLENGER.

the distal branches are much smaller and simple. The distal end of each branch bears a
spathilla with four to six short teeth.

Dimensions. — Length of the tubes 2'4 to 3'6, breadth 0'06 to 0'08.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

I

5. Aulodendron indicum, n. sp. (PI. 105, fig. l).

Eadial tubes cylindrical, irregularly curved, tapering gradually towards the two ends ; smooth in
the proximal half, irregularly branched in the distal half, with ten to twenty or more curved
branches. The proximal branches are very large, one-sixth to one-fourth as long as the tube and
irregularly ramified ; the distal branches are much shorter, also ramified or simple. All the branches
are more or less curved and bear a spinulate knob at the distal end.

Dimensions. — Length of the tubes 1*2 to 1'8, breadth 0'02 to 0'03 ; length of the branches
01 to 0-3.

Habitat. — Indian Ocean ; Coeos Islands (Eabbe), surface.

Order II. PH^EOSPH^IRIA, Haeckel, 1879.

Definition. — PH^EODARIA with a simple or double, usually spherical lattice-shell,
which is not bivalved and has no peculiar mouth or peristome. Central capsule placed
in the centre of the shell.

Family LXXIV. OROSPH^RIDA, n. fam. (Pis. 106, 107).

Definition. — PH^EODARIA with a big spherical (sometimes polyhedral or ellipsoidal),
very coarse shell, which is composed of thick bars containing an axial canal. Nodal
points of the coarse network without astral septa. Meshes of moderate size, irregularly
polygonal. Surface of the shell usually with radial spines and pyramidal elevations.
No peculiar mouth in the shell. Central capsule tripylean, in the centre of the shell.

The family Orosphserida comprises those PH^EODARIA which possess a simple
spherical or polyhedral lattice-shell, composed of hollow, very thick, non-articulate rods,
without a peculiar shell-mouth. They agree in the considerable size of the spherical lattice-
shell and the absence of a peculiar shell-mouth with the other Phseosphseria, but differ
from them in the coarse and irregular shape of the massive network, which is composed
of irregular polygonal meshes, separated by very thick concentrically stratified rods,
containing a fine axial canal. The closely allied Sagosphserida differ from them in the
delicate shape of the solid and very thin, filiform rods of the network, and its subregular

REPORT ON THE RADIOLARIA. 1591

triangular meshes. The Aulosphaerida differ in the development of the peculiar nodal
cavities and astral septa, by which the thin-walled cylindrical tubes "of the articulated
network are separated in the stellate nodal points. The Cannosphserida, closely allied
to these latter, also differ in the articulated network, and further in the possession of an
internal concentric shell. The Castanellida are sometimes similar to the Orosphserida,
but distinguished by a peculiar large shell-mouth and a network of different shape.

The Orosphserida belong to the biggest Radiolaria, and the lattice-work of their
spherical shell is of a ruder and coarser shape than in any of the other families of this
class. Nevertheless they have been hitherto perfectly unknown, and were first discovered
by the Challenger. We have been able to distinguish in the collection four genera and
twenty -seven species. This strange fact may be explained by the circumstance, that they
are in general rare, and restricted to a few localities, and that probably all the species
are inhabitants of great depths. Complete shells also are rarely found, whilst broken
fragments of their big shells, easily recognisable by the coarse irregular meshes and
the thick stratified bars, are met with frequently in the Radiolarian ooze of some Pacific
Stations, especially at Stations 265 and 268, at a depth of 2900 fathoms.

The lattice-shell of the Orosphaarida is usually spherical, or an endospherical poly-
hedron (PI. 106, fig. 4) ; rarely one axis is somewhat prolonged, so that the shell
becomes slightly ellipsoidal (PI. 106, fig. l). Its diameter is usually between 2 and 3,
often also between 2 and 1 mm., rarely more than 3, or less than 1 mm. The
largest shells observed attained 5 to 6, the smallest 0'5 to 0'6 mm. Their general
habit is very characteristic, so that they may be easily distinguished from all other
spherical lattice-shells, especially from the Castanellida and from the simple Monosphserida
(Cenosphera, Acanthosphcera), with which I confounded them in the beginning (hence
the first shell observed, figured in 1878, was placed among the Monosphserida in
PI. 12). A closer examination of the coarse network and of the peculiar structure of its
thick bars always enables one to recognise even small isolated fragments of broken shells.

The meshes of the coarse network exhibit in all observed Orosphserida a very irregular
form and unequal size ; the majority are usually more or less quadrangular, more rarely
they are triangular, pentagonal or hexagonal, very rarely rounded. They are often
arranged in parallel rows, which seem to be determined by prominent crests, connecting
the bases of the radial spines (PI. 12, fig. 1 ; PI. 106, fig. 4, &c.). The diameter of the
meshes is usually between 0'05 and O'l, often O'l to 0*2, rarely more than 0'25, or less
than 0'025 mm. In Oroplegma, which develops an outer loose, spongy shell around
the inner primary shell, the big meshes of the former become much larger and very
irregular (PL 107, fig. 1).

The coarse bars which separate the large meshes of the irregular network are very
thick and massive, cylindrical, usually of unequal thickness, straight or slightly curved,
never angular or prismatic. Their diameter is usually between O'Ol and 0'02, rarely

1592 THE VOYAGE OF H.M.S. CHALLENGER,

more than 0'03 or less than 0'005 mm. Their surface is either smooth or slightly
spinulate. Examined in the dry state and by strong lenses, they constantly exhibit a
fine, but distinct longitudinal striation, as the expression of concentric stratification. A
fine axial canal or central tubule is usually visible in the axis of each rod, and often this
axial canal is studded with numerous short lateral branches (PI. 107, figs. 2, 4, 8). But
very often the axial canals become rudimentary or lost, or are developed only in a part
of the bars (PI. 12, fig. 1). When they are completely developed, the entire network
of the shell is drained by a reticulate system of communicating axial canals ; they are
probably filled by jelly in the living body. This tubular system never attains that regu-
larity and high development which is constantly found in the Aulosphserida ; and the
characteristic stellate nodal points of the latter, with their astral septa, are never found in
any of the Orosphserida. Moreover the wall of the tubular bars is very thin and struc-
tureless in the Aulosphserida, very thick and stratified in the Orosphserida, the enclosed
canal very wide in the former, very narrow in the latter. The stratification of the con-
centric cylindrical lamella?, which surround the narrow axial canal, is effected by the
gradual deposition of the concentric layers, and is very similar to that which is found in
the thick spicula of many sponges. The peculiar structure of the bars in the Orosphserida
becomes very distinct if the skeleton be burned, or acted upon by fire for some time ; it
then assumes a brown colour and its surface often appears dimpled. Sometimes the
concave dimples on the surface of the bars are rather deep and separated by prominent
crests (PI. 107, figs. 4, 7). The few genera of Orosphserida which are here
distinguished have all the same structure, are closely allied, and differ mainly in the
shape of the outer surface of the lattice-sphere. The latter is quite simple and smooth
only in Orona. In the common Orosphcera (PI. 106, figs. 1-3) it is studded with
radial spines. In the most frequent form, Oroscena, the shell has a pyramidal or
tent-shaped elevation on the base of each radial spine, and usually the bases of the
neighbouring spines are connected by strong prominent crests, the edges of the three-
sided or four-sided pyramids (PL 12, fig. 1 ; PI. 106, fig. 4). This remarkable form
is more or less polyhedral, with concave sides, and is similar to the characteristic shells
which are represented by Auloscena among the Aulosphaerida, by Sagoscena and
Sagoplegma among the Sagosphserida (compare Pis. 108 and 110). The pyramids or
tents, however, are in these latter more regularly and distinctly developed than in the
Orosphserida. The radial spines which arise from the top of the pyramids are often
branched, and the branches become connected to form an outer enveloping secondary
shell or a loose spongy framework in Oroplegma (PI. 107, fig. 1).

The radial spines of the Orosphserida never exhibit a constant number or disposition in
the individual species ; their usual number is from twenty to sixty. Their form exhibits
two different types, which, however, are not sharply separated ; robust club-shaped and
slender rod-shaped spines. The robust club-shaped spines are usually about as long as

REPORT ON THE RADIOLARIA. 1593

the diameter of the shell ; they are longitudinally striped in the basal part, spinu-
late or reticulately dimpled in the distal part ; sometimes they are straight, at other
times curved or undulate (PI. 106, figs. 1-4 ; PL 107, figs. 4-6). The slender rod-
shaped spines are usually longer than the diameter of the shell, cylindrical, more or less
curved or even undulate, smooth or thorny, sometimes irregularly branched, and often
the branches are all or partly connected (PI. 106, fig. 3 ; PI. 107, fig. 1). In the
majority of the shells observed the radial spines were found to be partly broken off.
Their structure is the same as that of the bars of the network ; but the central axial
canal and the surrounding concentric lamellae are usually more distinct than in the latter.
The central capsule of the Orosphserida lies in the centre of the spherical lattice-
shell, surrounded by the voluminous calymma, which fills up its cavity. The form,
structure, and size of the central capsule are the same as in the closely allied Aulosphserida
(PI. Ill, fig. 2). Its diameter is usually about 0'2, or between 0'15 and 0'25, rarely
more than 0'3 or less than T2. The dark pha3odium is of about the same volume as the
central capsule, and envelops its oral half with the radiate operculum and the proboscis
of the astropyle. The two opposite parapylse are small.

Synopsis of the Genera of Orosphcerida.

I. Subfamily f Surface smooth, without radial spines, . 671. Orona.

Oronida.
Surface of the shell without pyramidal or 1 Surface studded with simple or branched radial

tent-shaped elevations. [ spines, ..... 672. Orosphcera.

TT o T_* -1 f Pyramids of the surface free, without spongy

11 ^SLid,

Surface of the shell with numerous pyra- p ^ of ^ ^^ connected b a

midal or tent-shaped elevations. ^ envelope or an external lattice-shell, 674. Oroplegma.

Genus 671. Orona,1 n. gen.

Definition. — 0 rosphaerida with a simple spherical or slightly ellipsoidal shell,
without pyramidal elevations and radial spines.

The genus Orona is the simplest of the Orosphaerida, and probably the common
ancestral form of this family. The lattice-shell is a simple fenestrated sphere, some-
times slightly ellipsoidal, with prolonged main axis, and bears on its surface neither
tent-shaped elevations nor radial spines. It may be confounded with some big forms
of Cenosphcera ; it differs, however, in the possession of hollow central canals in the thick
bars of the very coarse lattice-plate.

1 Orona — Hilly or tuberculate shell; fas, ">"!•
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 200

1594 THE VOYAGE OF H.M.S. CHALLENGER.

1. Orona maxima, n. sp. (PI. 107, fig. 5).

Shell spherical, with very irregular polygonal meshes. Bars of the loose network smooth or
slightly spinulate, very thick, with a pinnulate axial canal.

Dimensions. — Diameter of the sphere 5'0 to 5'5, of the meshes 0'2 to 0'4, of the bars O'Ol.
Habitat. — Central Pacific, Station 265, depth 2900.

2. Orona robusta, n. sp.

Shell spherical, with irregular quadrangular meshes (intermingled with single triangular,
pentagonal, and hexagonal meshes). Bars of the coarse network very thick, spinulate.
Dimensions. — Diameter of the sphere 3'0 to 3'6, of the meshes 0'05, of the bars 0'012.
Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Orona crassissima, n. sp. (PI. 107, fig. 7).

Shell ellipsoidal, slightly prolonged in the main axis, with irregular polygonal meshes of very
different sizes and unequal forms. Bars of the coarse network very thick, thorny and dimpled, their
surface being covered with a network of prominent polygonal crests.

Dimensions. — Diameter of the sphere 3'0 to 4'0, of the meshes 0'2 to 0-5, of the bars 0'02
to 0-06.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

Genus 672. Orosphcera,1 n. gen.

Definition. — 0 rosphserida with a simple, spherical (sometimes slightly ellip-
soidal or polyhedral) lattice-shell without pyramidal elevations, but with numerous
radial spines.

The genus Orosphcera differs from the preceding Orona, its ancestral form, in the
development of simple or branched radial spines. It bears, therefore, the same relation
to the latter that Acanthosphcera has to Cenosphcera. In the two latter genera,
however, the bars of the network are solid, in the two former hollow. The species
referred to Orosphcera are closely allied and require a further accurate examination.

Subgenus 1. Oronium, HaeckeL

Definition. — Radial spines simple, smooth or spiny, but neither branched nor
arborescent.

1 Orospli<cra = Sphere with hilly elevations; ojoj,

REPORT ON THE RADIOLARIA. 1595

1. Orosphoera hastigera, n. sp.

Eadial spines cylindrical, straight, smooth, simple, about as long as the diameter of the spherical
shell, and as broad as its smooth bars. Meshes of the network irregularly polygonal, the majority
quadrangular, of different sizes.

Dimensions. — Diameter of the sphere TO to 1/2, length of the radial spines I/I to 1/5,
middle breadth 0-004.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

2. Orosphcera spinigera, n. sp.

Eadial spines cylindrical, irregularly curved, thorny, simple, two to three times as long as the
diameter of the spherical shell, and as broad as its spiny bars. Meshes of the network irregularly
polygonal, the majority pentagonal.

Dimensions. — Diameter of the sphere 1'5 to T8, length of the spines 3'0 to 5'0, breadth O'OOG.

Habitat. — North Atlantic, Station 353, depth 2965 fathoms.

3. Orosphcera fusigera, n. sp.

Eadial spines slender, spindle-shaped, straight, smooth, about as long as the diameter of the
spherical or slightly ellipsoidal shell, in the thicker middle part five tunes as broad as the bars, and
tapering equally towards both ends. Meshes of the network irregularly polygonal, the majority
quadrangular, separated by smooth bars.

Dimensions. — Diameter of the shell 1/0 to 1/2, length of the spines 1/2 to 3/6, basal breadth
0-02, middle breadth 01.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

4. Orosphcera foveolata, n. sp.

Eadial spines spindle-shaped, straight, dimpled, half as long as the radius of the spherical shell
and three to five times as thick as the bars. Meshes irregular, polygonal, of very different shapes,
separated by dimpled bars. (Similar to Oroscena gegeribauri, PL 106, fig. 4, but with spherical
dimpled shell, without pyramidal elevations.)

Dimensions. — Diameter of the shell 2'0 to 2'4, length of the spines 0'05, breadth 015.

Habitat. — Central Pacific, Station 267, depth 2700 fathoms.

5. Orosphcera serpentina, n. sp. (PI. 106, fig. l).

Eadial spines cylindrical, dimpled, undulate or curved in a snake-like manner, about as long as
the diameter of the ellipsoidal or spherical shell and four to six times as broad as its smooth bars.
Meshes very irregular, polygonal.

Dimensions. — Diameter of the shell I'O to 1'2, length of the spines 012 to 015, breadth 012.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

1596 THE VOYAGE OF H.M.S. CHALLENGER.

6. Orosphcera horrida, n. sp. (PL 106, fig. 2).

Eadial spines club-shaped, very strong, straight, about as long as the diameter of the polyhedral
shell, ovate and smooth in the distal half, slenderly conical, and armed with recurved spines in the
proximal half ; their outer third is the thickest, and five times as broad as the smooth bars of the
coarse network. Meshes of the latter irregularly quadrangular.

Dimensions. — Diameter of the shell 1'2 to 1'6, length of the spines 1'2 to 2'0, breadth 0'2.

Habitat. — South Pacific, Station 291, depth 2250 fathoms.

7. Orosphcera clavigera, n. sp.

Eadial spines club-shaped, thickened towards the distal end, more or less curved, spinulate,
about as long as the diameter of the spherical shell ; in the distal third four to six times as broad
as the spinulate bars. Meshes irregularly polygonal, the majority pentagonal.

Dimensions. — Diameter of the shell 2'0 to 2'5, length of the spines 1'8 to 2'2, breadth 016.

Habitat. — Central Pacific, Station 263, depth 2650 fathoms.

Subgenus 2. Orothamnus, Haeckel.
Definition. — Radial spines branched or arborescent.

8. Orosphcera ramigera, n. sp.

Eadial spines cylindrical, spinulate, straight, about twice as long as the diameter of the
spherical shell and as thick as its spinulate bars. Numerous simple spinulate branches, straight or
slightly curved, and two to four times as long as the meshes, are irregularly scattered, and
arise nearly perpendicularly from the bars.

Dimensions. — Diameter of the shell 2'0 to 2'2, length of the spines 4 to 5, breadth 0'05.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

9. Orosphcera furcata, n. sp.

Eadial spines cylindrical, smooth, irregularly curved, about as long as the radius of the
spherical shell and as thick as its smooth bars, forked at the distal end, with two or three terminal
branches of various lengths. Meshes irregularly polygonal (the majority hexagonal).

Dimensions. — Diameter of the shell T2, length of the spines 0'7, breadth 0'03.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface (?).

10. Orosphcera confluens, n. sp.

Eadial spines cylindrical, smooth, irregularly curved, two to three times as long as the diameter
of the polyhedral shell, twice as broad as its smooth bars, bearing numerous irregular, lateral

REPORT ON THE RADIOLARIA. 1597

branches, which are partly confluent and fenestrated (similarly as in PL 107, fig. 1), but not
forming an outer lattice-shell. Meshes irregularly polygonal.

Dimensions. — Diameter of the shell 3'3, length of the spines 6 to 9, breadth 0'03.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

11. Orosphcera arborescens, n. sp. (PI. 106, fig. 3).
Oroihamnus arborescens, Haeckel, 1881, Atlas, loe. cit.

Eadial spines cylindrical, rough, more or less curved, somewhat longer than the diameter of
the subspherical or slightly ellipsoidal shell, and at the thicker base three times as broad as its
smooth bars, bearing numerous irregularly branched and curved, sometimes confluent, lateral
branches. Meshes irregularly quadrangular.

Dimensions. — Diameter of the shell 1'2 to T6, length of the spines 1'5 to 2'2, breadth 0'06.

Habitat. — South Atlantic, Station 335, depth 1425 fathoms.

Genus 673. Oroscena,1 n. gen.

Definition. — Orosphserida with a simple, polyhedral or subspherical lattice-
shell, and with numerous pyramidal elevations on its surface, the top of which bears a
radial spine.

The genus Oroscena differs from the preceding Orosphoera in the possession of
numerous pyramidal or tent-shaped elevations, each of which bears on its top a radial
spine. It exhibits therefore the same relation to the latter that Sagoscena does to
Sagosphcera and Auloscena to Aulosphcera. The bases of the radial spines are usually
connected by prominent concave crests, the edges of the pyramids. The species
described of Oroscena seem to be very variable and transformistic.

Subgenus 1. Oroscenium, Haeckel.

Definition. — Radial spines simple, smooth or spiny, but neither branched nor
forked.

1. Oroscena gegenbauri, n. sp. (PL 106, fig. 4).

Eadial spines club-shaped, about half as long as the radius of the shell, cylindrical and finely
sulcate in the basal third, ovate and elegantly dimpled in the distal two-thirds. The bases of the
radial spines are connected by prominent concave crests, which form the edges of the polyhedral
shell. Meshes irregularly polygonal, the majority quadrangular, separated by denticulate bars.

1 Oroscena =Shell with tent-shaped elevations ; ojof,

1598 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Diameter of the shell (without spines) 1/2 to 1/8, of the meshes 0-04 to 01;
length of the spines 0-3 to 0-5.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

2. Oroscena mulleri, n. sp. (PL 107, fig. 8).1

Radial spines club-shaped, very similar to that of the preceding species, but much larger,
about as long as the radius of the shell. Meshes irregularly polygonal, the majority pentagonal,
separated by smooth bars.

Dimensions. — Diameter of the shell 2'0 to 2'4, length of the spines 1/0 to 1/2.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

3. Oroscena cuvieri, n. sp. (PI. 107, fig. 6).

Eadial spines club-shaped, compressed and smooth in the proximal half, spindle-shaped and
dimpled in the distal half, about as long as the radius of the shell. Meshes irregularly polygonal,
the majority hexagonal, separated by denticulate bars.

Dimensions. — Diameter of the shell 1/5, length of the spines O'S.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

4. Oroscena bcerii, n. sp. (PI. 107, fig. 4).

Eadial spines nearly spindle-shaped, undulate, tapering from the thicker middle towards both
ends, coarsely dimpled, about one-third as long as the radius of the shell. Meshes irregularly
polygonal, the majority pentagonal, separated by spinulate bars.

Dimensions. — Diameter of the shell 3"2, length of the spines I'O to 1/2, breadth O'l.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

5. Oroscena wolffii, n. sp.

Eadial spines cylindrical, spinulate, more or less curved, longer than the diameter of the shell
and about twice as broad as its bars. Meshes irregularly polygonal, of very variable form and
unequal size, separated by smooth bars.

Dimensions. — Diameter of the shell 2'5, length of the spines 3'0 to 3'5, breadth 0'02.

Habitat. — Indian Ocean, Zanzibar (Pullen), depth 2200 fathoms.

Subgenus 2. Orodendrum, Haeckel.
Definition, — Radial spines branched or arborescent.

1 In the plate the number is omitted by mistake. The figure is above in the middle.

REPORT ON THE RADIOLARIA. 1599

6. Oroscena huxleyi, n. sp. (PI. 12, figs. 1, la).

Eadial spines cylindrical, obliquely ascending and irregularly curved, about as long as the
diameter of the shell and somewhat thicker than its thorny bars. A variable number of short,
irregular, partly simple, partly forked, lateral branches arises from the spines. Meshes of the
network very irregular, partly solid, partly hollow (fig. la*), the majority quadrangular. This species,
the first observed form of Orosphaerida (captured the 21st February 1873 at Station 5), was at the
beginning of my observations, in 1876, and when I had no knowledge of the central capsule,
erroneously regarded by me as a gigantic Sphseroid (of the Monosphasrida) and therefore placed
in PL 12. The long branched spines, afterwards observed complete in another specimen, were
broken off in the specimen first figured.

Dimensions. — Diameter of the shell 2'0 to 2'5, length of the spines 2 to 3 mm., breadth 0'03.

Habitat. — North Atlantic (west of Canary Islands), Station 5, depth 2740 fathoms.

7. Oroscena darwinii, n. sp.

Eadial spines cylindrical, irregularly curved and branched, about twice as long as the diameter
of the shell ; the branches are all again ramified and partly confluent (as in PL 107, fig. 1). The
branches and the bars of the network are of equal breadth, smooth (not thorny as in the similar
preceding species). Meshes rather subregular, quadrangular.

Dimensions. — Diameter of the shell 24 to 2'8, length of the spines 4 to 5 mm., breadth 0'015.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

8. Oroscena duncanii, n. sp.

? Hexactinellida didyonina, Martin Duncan, 1881, Journ. Eoy. Micr. Soc., p. 175, pi. iii. figs. 4, 6.

Eadial spines cylindrical, thorny, arborescent, somewhat shorter than the diameter of the shell,
with irregular ramified branches (similar to Orosphcera arborescens, PL 1Q6) fig. 3). The size and
ramification of the arborescent spinulate branches decrease towards the apex. The thicker branches
are from two to three times as broad as the spinulate bars of the network. Meshes of the latter
irregular, the majority quadrangular.

Dimensions. — Diameter of the shell 3'2, length of the spines 3'5 to 4'5, breadth 0'02 to 0'3.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms ; coast of Portugal, 1095 fathoms.

Genus 674. Oroplegma,1 n. gen.

Definition. — Or osphser ida with a spongy, spherical or slightly polyhedral
lattice-shell, which is enveloped by a loose spongy framework and bears numerous
radial spines.

The genus Oroplegma differs from the other Orospheerida in the development of an
external lattice-work enveloping the internal primary shell, and produced by the union

1 Oroplegma= Hilly shell of framework; o>j,

1600 THE VOYAGE OF H.M.S. CHALLENGER.

of the branches of the radial spines. This outer shell is either a simple lattice-plate
(comparable to the cortical shell of Diplosphcera), or a spongy framework (as in Rhizo-
plegma).

Subgenus 1. Oroplegmium, Haeckel.

Definition. — External shell a simple fenestrated lamella, forming an outer
concentric lattice-sphere around the inner primary shell.

1. Oroplegma diplosphaera, n. sp. (PI. 107, fig. 1).

Radial spines slender, cylindrical, smooth, more or less curved, about twice as broad as the
smooth bars of the network. External shell a simple irregular lattice-sphere, with loose polygonal
meshes,' which are on an average three to four times as broad as the irregular meshes of the
internal shell. The free prominent parts of the radial spines are irregularly branched, very long,
with partly confluent branches.

Dimensions. — Diameter of the inner sphere 1'5 to 2'0, of the outer 2 "5 to 3-0 ; length of the
free spines 1'2, breadth 0-04.

Habitat. — Central Pacific, Station 265, depth 2900 fathoms.

2. Oroplegma spinulosum, n. sp.

Radial spines slender, cylindrical, thorny, more or less curved, very similar to those of the
preceding species ; the shell also much resembles that of Oroplegma perplexum. It differs from the
latter in the more regular fenestration of both shells, and mainly in the shape of the bars and
the spine-branches, which are all spinulate and densely studded with small conical thorns.

Dimensions. — Diameter of the inner sphere 1'5 to 2-0, of the outer 2'5 to 3'0 ; length of the
spines 1/2, breadth 0'03.

Habitat. — Central Pacific, Station 268, depth 2900 fathoms.

3. Oroplegma velatum, n. sp.

Radial spines stout, cylindrical, somewhat club-shaped, spiny, slightly curved, about three to
four times as broad as the thorny bars of the network. External shell a simple lattice-sphere with
irregular polygonal meshes, which are for the most part pentagonal and about four times as broad
as the polygonal meshes of the inner shell. The free prominent parts of the radial spines are
thickened, club-shaped, and about as long as the radius.

Dimensions. — Diameter of the inner sphere2-0 to 24, of the outer 2 '8 to 3'6 ; length of the
free spines 0'5 to 0'7, breadth 012 to 0'15.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

REPORT ON THE RADIOLARIA. 1601

Subgenus 2. Orodictyum, HaeekeL

Definition. — External shell a complex framework, forming an outer spongy envelope
around the inner primary shell.

4. Oroplegma spongiosum, n. sp. (PL 107, fig. 3).

Radial spines stout, cylindrical, spinulate, slightly curved, three to five times as broad as the
inner rough bars. External shell with pyramidal elevations, forming a loose spongy framework,
the irregular polygonal meshes of which are two to five times as broad as those of the enclosed
internal shell ; the thickness of the spongy envelope equals about half the radius of the inner shell.
External free prolongations of the radial spines about equal to the radius.

Dimensions. — Diameter of the inner sphere 2 to 2 '5, of the outer 3 to 3-5 ; length of the free
radial spines 0'5 to 2'0, breadth 01.

Habitat. — North Pacific, Station 241, depth 2300 fathoms.

5. Oroplegma giganteum, n. sp. (PL 107, fig. 2).

Eadial spines slender, cylindrical, spinulate, irregularly curved, about twice as broad as the
spinulate tubular bars of the network (fig. 2). External shell an irregular, loose, spongy framework,
the polygonal meshes of which are three to six times as broad as the rounded irregular meshes of
the inner shell ; the thickness of the spongy envelope about equals the radius of the inner shell.
External free prolongation of the radial spines irregularly branched.

Dimensions. — Diameter of the inner sphere 3'2 to 3-5, of the outer 5-4 to 6'6 ; length of the
free spines 1'4 to 1*5, breadth 0'03.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Family LXXV. SAGOSPH^ERIDA, n. fam. (PL 108).

Definition. — PH^EODARIA with a large spherical (or sometimes polyhedral), very
delicate shell, which is composed of solid, very thin and long threads. Nodal points of
the arachnoiclal network without astral septa. Meshes large, triangular. Surface of the
shell usually armed with radial spines and often studded with pyramidal elevations. No
peculiar mouth in the shell. Central capsule tripylean, in the centre of the shell.

The family Sagosphserida comprises a rather large number of common and widely
distributed PH^ODARIA, which in respect of the special form and differentiation of the
shell exhibit the greatest similarity to the common Aulosphserida, but differ essentially
from them in the peculiar structure of the network. This is not composed of stout
hollow cylindrical tubes, but of solid, very thin threads ; and these fine arachnoidal

(ZOOL. CHALL. ESP. — PAET XL. — 1886.) Rr 201

1602 THE VOYAGE OF H.M.S. CHALLENGER. '

threads are simply united or confluent at the nodal points, and are not connected by a radial
or stellate septal junction, as in the Aulosphserida. There are, therefore, neither astral
septa nor a nodal cavity in each nodal point. The delicate shape of the thin and fragile
threads separates the Sagosphserida from the closely allied Orosphserida, the thick bars
of which contain a central axial canal and exhibit a concentric structure. Another differ-
ence between these two similar families is indicated by the form of the meshes of the
network, which are constantly triangular in the Sagosphserida, but irregularly polygonal
or quadrangular in the Orosphserida. The general habit of these two families, however,
is very different, since the big and stout spheres of the Orosphserida are the coarsest and
rudest spherical shells of all Radiolaria, whilst the fragile and delicate spheres of the
Sagosphserida represent the finest and most tender in the whole class.

The spherical lattice-shell of the Sagosphserida has a considerable size, its diameter
being usually between one and three millimetres, rarely less or more. Some species are
very common and widely distributed, usually accompanying the common Aulosphserida ;
very frequently the similar shells of the two are found interwoven. But in spite
of this frequency and visible size, the Sagosphserida have hitherto almost completely
escaped the attention of observers. The main cause of this strange fact may be their
extreme delicacy and fragibility, so that complete and intact shells occur very rarely, the
majorit)'' being more or less broken and incomplete. It seems that only two species of
Sagosphserida have been hitherto observed.

The first form described is Sagmarium trigonizon, observed by me in 1859 living at
Messina, and figured in 1862 in my Monograph as Dictyosoma trigonizon (Taf. xxvi. figs.
4-6), but afterwards called Spongodictyum trigonizon (loc. cit., p. 459). I supposed at
that time (now twenty-five years ago), that this remarkable and in many respects distinct
form might belong to the Spongosphserida, and that an internal, triple, spherical lattice-
shell, found entangled in its spongy framework, might be its central " medullary shell."
But at present, having found many shells of different Radiolaria accidentally entangled
in the arachnoidal framework of various Sagosphserida, I think it much more probable,
that that " triple medullary shell," composed of three simple concentric lattice-spheres,
was really a species of Plegmosphcera or . Actinomma, accidentally entangled in the
arachnoidal spongy framework of Sagmarium. This is the more probable, as I had
observed very frequently at Messina, in 1859, fragments of that framework, but only
once the triple lattice-shell which I supposed to be the "triple medullary shell" of the
former. The peculiar structure of the loose framework, its very large triangular meshes
and thin arachnoidal bars, partly provided with cruciate verticils (loc. cit., Taf. xxvi.
figs. 4, 5) have been very frequently observed by me during the last ten years in various
Sagosphserida (PH^EODARIA), but never in any true Sphseroidea (SPUMELLARIA).

The second species of Sagosphserida hitherto observed, is Sagoscena gracilis,
described and figured in 1879 by Richard Hertwig as Aidospliara gracilis (Organism.

REPORT ON THE RADIOLARIA. 1603

d. Radiol., p. 91, Taf. ix. fig. 4). He too observed only fragments of destroyed
and incomplete shells, and was led by their striking similarity to fragments of
AulospJuera elegantissima to unite it with the genus Aulosphosra. But the accurate
description and the figure given by him of the fragments observed leaves no doubt
that it was a true Sagoscena.

In the collection of the Challenger the Sagosphserida are so common and so richly
represented, that we may describe here not less than seven genera and thirty-three
species, but this may be a small part only of the numerous species of this family, which
seems to be widely distributed over all oceans, in the Arctic and Antarctic as well
as in temperate and tropical zones. The majority are inhabitants of the surface, but a
few species have been found only in deep-sea soundings. A striking fact is their usual
association with the similar Aulosphsericla. The majority of shells of both families
were found entangled in one another.

The shell of all Sagosphserida seems to be spherical or nearly spherical in the complete
state ; but complete spheres can be observed only very rarely, and it is not impossible
that deviations from the spherical form exist just as in some Aulosphserida (e.g., the
lenticular Aulophacus and the spindle-shaped Aulatractus). The diameter of the
spheres usually seems to be between 1 and 2, often also 3 millimetres ; very rarely
shells occur which are less than 1 or more than 3 (4 or 5) millimetres.

The siliceous network or lattice-work of the Sagosphserida exhibits a very character-
istic shape, and this enables one to distinguish it at first sight from all the other Radiolaria,
It is constantly composed of triangular, very large meshes, which are separated by very
thin and delicate, flexible and elastic bars. With respect to the arrangement of these
meshes we distinguish two different subfamilies ; in the Sagenida the wall of the spherical
shell is very thin and composed only of a simple lattice-plate ; in the Sagmarida the
wall is thickened and spongy, with a complete wicker-work of threads, interwoven in
different directions.

The typical triangular form of the large meshes is usually regular or subregular in
the fenestrated Sagenida, more or less irregular in the spongy Sagmarida. In many
cases, however, irregular triangles also occur in the former, and regular triangles in the
latter subfamily. Very rarely irregular polygonal meshes are found in a part of the
network, small connecting bars being developed accidentally between two neighbouring
sides of the triangles. The diameter of the meshes is usually between O'l and 0'2 mm.,
often also greater, between 0'2 and 0'3, rarely smaller, 0'05 to 0"09 mm. The triangular
meshes of the Sagosphaerida are therefore on an average ten times as large as the usual
meshes in the network of the common Sphseroidea.

The filiform bars, or the thread-shaped, very long and thin rods between the
triangular meshes, are scarcely less characteristic of the Sagosphserida than the form and
size of the meshes. Their length is usually between O'l and 0'2 mm., often also

1604 THE VOYAGE OF H.M.S. CHALLENGER.

from 0'2 to 0*3 mm., whilst their thickness is only 0'002 to 0'004 mm., often it is less
than O'OOl, rarely more than 0'005 mm. The nodal points of the network, in which six
threads are usually united, are more or less thickened, often stellate (PI. 108, figs. 9,
12, &c.). Sometimes they are pierced by a central pore. The thin threads are constantly
cylindrical, never edged or prismatic, very elastic and flexible ; usually they are
perfectly smooth, rarely spiny or thorny, sometimes provided with scattered cruciate
verticils of lateral branches, as in Sagena crucifera and in the first described form of
this family, Sagmarium trigonizon (compare my Monograph, 1862, Taf. xxvi. fig. 5).

The surface of the spherical shell is smooth only in two genera of Sagosphaerida, in
Sagena and Sagmarium (PI. 108, figs. 2, 8). In the five other genera it is covered
either with radial spines, arising from the nodal points of the network, or with peculiar
cortical pyramids or tent-shaped elevations (PI. 108, figs. 1, 3—6, &c.). These
pyramids are of the same characteristic shape as in the similar Auloscena among the
Aulosphserida (PL 110, fig. 1); usually, however, they are less regular than in the
latter. The pyramids or tents are usually six-sided, often, however, they are also four-
sided or three-sided, more rarely five, seven or more sided. The edges of the pyramids
are formed by filiform bars similar to those which compose the original lattice-work of
the Sagosphserida. The cavity of the pyramids is quite simple in Sagoscena (figs. 1, 5, 6),
whilst in Sagenoscena and Sagoplegma a radial column arises in its axis, the thickened
axial rod (figs. 3, 4, 10).

The radial spines, which arise either from the tops of the pyramids or from the
nodal points of the network, exhibit in the Sagosphserida a variety and elegance similar
to the closely allied Aulosphserida. Sometimes a single radial spine arises in each nodal
point or at the top of each pyramid (figs. 3, 4, 10) ; at other times two, three, or four
(rarely more) divergent spines (figs. 6—9, 12, 13). These are rarely quite simple, usually
provided with lateral and terminal branches. The lateral branches are either scattered
irregularly, or regularly disposed in elegant verticils, each of which is usually composed
of three or four short branches (PI. 108, figs. 9, 13). The terminal branches form
either a similar verticil, or a bunch or corona, composed of numerous radial secondary
spines. The distal ends of the terminal as well as of the lateral branches are rarely
simple, usually they are provided with a spinulate knob or with an elegant spathilla
(PI. 108, figs. 3, 9, 13).

The central capsule of the Sagosphserida is comparatively small, as it also is in the
Aulosphaerida and Orosphserida. Its diameter is usually about one-third or one-fourth
that of the enveloping shell, between 0'2 and 0'3, often only 0'12 to 0'18, rarely more than
0'3 mm. It is surrounded on the oral half by a red or dark phseodium and separated from
the inner surface of the shell by the voluminous calymma. The subspherical nucleus
is usually about half as broad as the capsule. The three openings of the latter, the
large tubular astropyle and the two opposite lateral parapylse, exhibit the same shape

REPORT ON THE RADIOLARIA.

1605

as in the closely allied Aulosphserida (PL 111, fig. 3). The pseudopodia arising from
the central capsule form a loose network in the calymma, and proceed over its surface
as numerous delicate radial filaments, often supported by the radial spines.

Synopsis of the Genera of Sagosphcerida.

I. Subfamily

Sagenida.

"Wall of the spherical
shell composed of
a simple lattice-
plate, with or
without pyra-
midal elevations.

II. Subfamily

Sagmarida.

Wall of the spherical
shell spongy, com-
posed of an irre-
gular complicated
wicker-work.

Surface of the spherical shell
smooth or spiny, without
pyramidal elevations.

No radial spines, surface smooth,
Eadial spines in the nodal points,

I" Pyramids without internal axial

Surface of the spherical shell rod, ....
covered with pyramidal <
or tent shaped elevations. j Pyramids with an internal radial

[ axial rod,

c c ,i , • i i. 11 { Surface smooth, without radial
Surface of the spherical shell

smooth or spiny, without -i. ie '

pyramidal elevations. [ gurface gtudded with radial gpineS)

Surface of the spherical shell j Pyramids on the top with a radial
covered with pyramidal 1 spine or a bunch of divergent
elevations. ( spines,

675. Sagena.

676. Sagosphctra.

677. Sagoscena.

678. Sagenoscena.

679. Sagmarium.

680. Sagmidium.

681. Sagoplegma.

Subfamily 1. SAGENIDA, Haeckel.

Definition. — S agosphserida with a delicate spherical shell, the thin wall of
which is composed of a simple lattice-plate, not spongy.

Genus 675. Sagena,1 n. gen.

Definition. — S agosphserida with a delicate spherical shell, the thin wall of
which is composed of a simple smooth lattice-plate, without radial spines.

The genus Sagena is the simplest of the Sagosphaerida and may be regarded as the
common ancestral form of this family. The delicate wall of the simple spherical lattice-
shell is composed of large, regular, or subregular, triangular meshes, the nodal points of
which bear no radial spines. It agrees therefore perfectly with Aularia, and differs from
this simplest form of Aulosphserida only in the structure of the skeleton, which is
composed not of hollow articulated tubes, but of very thin solid threads. The skeleton
may therefore also be confounded with Cenosphcera, but the central capsule of this
latter is " peripylean," with numerous fine pores in the entire wall, whilst that of Sagena
is " tripylean," having the proboscis of all PH^EODARIA.

1 Sagena= Drag-net; atnyr,vi\.

1606 THE VOYAGE OF H.M.S. CHALLENGER.

1. Sagena ternaria, n. sp. (PI. 108, fig. 8).

Network subregular, with equilateral triangular meshes, intermingled with single irregular
meshes (fig. 8). Bars of the network smooth, its nodal points solid, not pierced.

Dimensions. — Diameter of the spherical shell 1'5 to 2'5, length of the bars 01 to 0-2, breadtli
0-002 to 0-005.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, surface.

2. Sagena pertusa, n. sp.

Network subregular, with nearly equal triangular meshes. Bars of the network smooth, its
nodal points pierced by a circular hole.

Dimensions. — Diameter of the shell T2 to T8, length of the bars 0'2 to 0'25, breadth O'OOS.
Habitat. — Central Pacific, Stations 270 to 274, surface.

3. Sagena triangula, n. sp.

Network very regular, with equilateral triangular meshes. Bars of the network spinulate, like
those of Sagoplegma spinulosa (PI. 108, fig. 14), its nodal points solid, not pierced.
Dimensions. — Diameter of the shell 2'2, length of the bars 0'25, breadth 0'004.
Habitat. — South Atlantic, Station 325, surface.

4. Sagena crucifera, n. sp.

Network more or less irregular, with unequal triangular meshes. Bars of the network studded
with scattered, rectangular, minute crosses, arising perpendicularly, each cross composed of four
small equal bars. Nodal points partly solid, partly pierced by a hole. Network very similar to
that of Dictyosoma trigonizon, figured in my Monograph, Taf. xxvi. figs. 4, 5.

Dimensions. — Diameter of the shell T5, length of the bars 01 to 0-2, breadth 0'003.

Habitat. — Mediterranean, Atlantic, Canary Islands, Station 353, surface.

Genus 676. Sagosplicera,1 n. gen.

Definition. — S agosphserida with a delicate spherical shell, the thin wall of
which is composed of a simple lattice-plate, and bears on its nodal points radial spines.

The genus Sagosphcera differs from the preceding Sagena, its ancestral form, in the
development of radial spines on the nodal points of the simple delicate lattice-sphere.
It exhibits therefore the same relation to the latter as Aulosphcera bears to Aularia.

1 Sagospluera = Spherical armour ; aayn, <7<p«/{ «.

REPORT ON THE RADIOLARIA. 1607

The regular or subregular triangular meshes of fhe lattice-sphere are separated in
Sagosphcera by solid, very thin threads, in the similar Aulosphcera, however, by thicker
hollow tubes. The genus Sagosphcera may be divided into two subgenera : —
Sagosphcerella with a single radial spine at each nodal point of the network, and
Sagosphceroma with a bunch of two to four or more divergent radial spines.

1. Sagosphcera trigonilla, n. sp.

Badial spines simple, straight, smooth, about as long as the smooth bars of the network, a
single one at each nodal point. Meshes very regular, of equal size, equilateral triangular.
(Similar to the common Aulosphcera trigonopa.)

Dimensions. — Diameter of the sphere T2 to l-8, length of the bars 01 to 0'2, breadth 0-002
to 0-006.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Pacific, surface.

2. Sagosphcsra penicilla, n. sp. (PI. 108, fig. 10).

Eadial spines straight, stout, a single one at each nodal point, twice as thick, but of the same
length as the smooth bars of the network, armed at the distal end with a brush of numerous thin
radial bristles. (Very similar to Sagenoscena pencillata, but without pyramidal elevations on the
surface of the sphere.)

Dimensions. — Diameter of the sphere I'O to 1'5, length of the bars 01 to 015, breadth 0-002 to
0'004.

Habitat. — Antarctic Ocean, Station 154, surface.

3. Sagosphcera verticilla, n. sp.

Eadial spines slender, slightly curved, a single one at each nodal point, armed with three to five
cruciate verticils, each of which is composed of four crossed lateral branches with spinulate terminal
knobs (similar to Sagmidium crucicorne, PL 108, fig. 9), but with a spherical shell, having a simply
latticed, and not a spongy wall.

Dimensions. — Diameter of the sphere 2'0 to 2'5, length of the bars 01 to 0'2, breadth 0'002.

Habitat. — North Pacific, Station 256, surface.

4. Sagosphcera furcilla, n. sp. (PI. 108, figs. 11, lla).

Eadial spines short, spinulate, with a spiny terminal knob (fig. lla), two or three arising from
each nodal point of the network in divergent directions, only one-third or one-fourth as long as
its smooth bars. Meshes more or less irregular, triangular.

Dimensions. — Diameter of the sphere 2-2, length of the bars 0-2 to 0'3, breadth 0'004.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

1608 THE VOYAGE OF H.M.S. CHALLENGER.

5. Sagosphcera coronilla, n. spt

Kadial spines slender, smooth, three to six arising from each nodal point of the network in
divergent directions, about as long as its smooth bars, crowned at the distal end with a bunch of
twenty to thirty radial terminal branches, and provided with a spinulate knob at the distal end
(similar to Sagenoscena stellata, PL 108, fig. 3).

Dimensions. — Diameter of the sphere 3'0, length of the bars 01 to 0'2, breadth 0'002.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Genus 677. Sagoscena,1 n. gen.

Definition. — Sagosphserida with a delicate spherical shell, the thin wall of
which is composed of a simple lattice -plate and covered with numerous pyramidal
elevations ; each pyramid bears on its top one or more radial spines, but has no axial
rod in its radial axis.

The genus Sagoscena, and the following closely allied Sagenoscena (both very
common and widely distributed), exhibit a peculiar and very remarkable structure of
the delicate lattice-shell, similar to that which Auloscena represents among the Aulo-
sphaerida. The surface of the simple spherical lattice-shell is covered with numerous
pyramidal or tent-shaped elevations. These elegant and delicate pyramids are, how-
ever, in Sagoscena usually not so regular as in the similar Auloscena; the edges of
the pyramids are in the latter hollow cylindrical tubes, in the former thin solid
threads. The top of each pyramid usually bears a bunch of apical spines.

1. Sagoscena castra, n. sp. (PL 108, fig. l).

Pyramids subregular, of equal size and similar form, usually three-sided, crowned at the top
with three divergent apical spines, which alternate with the three edges of the pyramids and bear
a small spinulate terminal knob. (Some four-sided and single five-sided pyramids are often inter-
mingled with the three-sided.)

Dimensions. — Diameter of the sphere 17 to 2'3, length of the bars 0'2 to 0'25, breadth O'OOS.

Habitat. — South-Eastern Pacific, Stations 295, 296, surface.

2. Sagoscena tentorium, n. sp. (PL 108, fig. 6).

Pyramids subregular, of equal size and similar form, usually four-sided, crowned at the top
with three divergent apical spines, which are trifurcate at the distal end. (Some three-sided and
five-sided pyramids are often intermingled with the four-sided.)

Dimensions. — Diameter of the sphere 2'2, length of the bars 0'2 to 0'25, breadth O'OOo.

Habitat. — South Pacific, Station 291, surface.

1 Sagoscena= Armour with tents ; adyn, ffxnnj.

REPORT ON THE RADIOLARIA. 1609

3. Sagoscena prsetonum, n. sp. (PI. 108, fig. 7).

Pyramids subregular, of equal size and similar form, usually four-sided, crowned at the distal
top with three or four divergent apical spines, which bear some irregular verticils of lateral and
terminal branches. (Some five-sided and some six-sided pyramids are often intermingled with the
four-sided.)

Dimensions. — Diameter of the sphere 2-6, length of the bars 0'3, breadth O'OOG.

Habitat. — Central Pacific, Stations 271 to 274, surface.

4. Sagoscena pellorium, n. sp. (PI. 108, fig. 5).

Pyramids subregular, of equal size and similar form, usually five-sided or six-sided, crowned
at the distal end with three to six divergent apical spines, which bear an irregularly spinulate
terminal knob. (The size and form of the apical spines is here very variable, as well as the number
of the edges of the pyramids, which -varies between three and six.)

Dimensions. — Diameter of the sphere 3'2, length of the bars O15 to 0'25, breadth O'OOS.

Habitat. — Antarctic Ocean, Station 156, surface.

5. Sagoscena cruciarium, n. sp.

Pyramids subregular, usually six-sided (intermingled with single five-sided and seven-sided or
eight-sided forms), crowned at the distal top with three divergent, slender, apical spines, each of
which bears three to six regular cruciate verticils ; the four crossed lateral branches of each
verticil bearing a spinulate terminal knob. (Similar to Sagoplcgma scenophora, PL 108, fig. 13.)

Dimensions. — Diameter of the shell 2 '5, length of the bars 0'2 to 0'3, breadth 0'004.

Habitat. — North Pacific, Stations 240 to 244, surface.

6. Sagoscena debilis, n. sp.

Pyramids more or less irregular, with four, five, or six sides, of somewhat different form and
unequal size ; crowned at the top with one, two, or three slender apical spines, of variable length.
These spines as well as the bars of the network bear scattered cruciate verticils, each usually
composed of four crossed, small, lateral branches.

Dimensions. — Diameter of the shell 2 to 3'0, length of the bars 01 to 0'15, breadth 0'003.

Habitat. — Central Pacific, Stations 263 to 274, surface.

7. Sagoscena gracilis, Haeckel.

Aulospluira gracilis, R. Hertwig, 1879, Organism, d. Radiol., p. 91, Taf. ix. fig. 4.

Pyramids more or less irregular, with five, six, or seven sides, often of somewhat different form
and unequal size ; crowned at the top with a single radial spine, which has the same size as the

(ZOOL. CHALL. EXP.— PART XL. — 1886.) Rr 202

1610 THE VOYAGE OF H.M.S. CHALLENGER.

bars of the network, and bears in its distal half four cruciate verticils, each composed of four
crossed and curved horizontal branches.

Dimensions. — Diameter of the sphere 1 to 2, length of the bars 0'08 to 0-09, breadth 0-002.

Habitat. — Mediterranean (Messina), surface.

8. Sagoscena fragilis, n. sp.

Pyramids very irregular, with four to eight sides, of different form and unequal size ; crowned
at the top with a single, slender, radial spine, of the same thickness as the slender bars of the net-
work ; the latter as well as the former are smooth, without lateral branches.

Dimensions. — Diameter of the sphere TO to 2-0, length of the bars 01 to 0'2, breadth
0-001 to 0-002.

Habitat. — Cosmopolitan ; Atlantic, Pacific, surface.

Genus 678. Sagenoscena,1 n. gen.

Definition. — S agosphaerida with a delicate spherical shell, the thin wall of
which is composed of a simple lattice -plate and covered with numerous pyramidal
elevations ; each pyramid bears on its top one or more radial spines, and has an
internal axial rod in its radial axis.

The genus Sagenoscena differs from the preceding closely allied Sagoscena in
the possession of an internal radial axial rod, which arises in the centre of the base of
each pyramid, and is prolonged usually over its apex into a free, radial, apical spine.
The distal end of the latter is usually armed with a bunch of terminal teeth or bristles.
In the similar Sagoscena the internal cavity of the pyramids is simple, without axial rod.

1. Sagenoscena stellata, n. sp. (PL 108, fig. 3).

Pyramids rather regular, usually six-sided (intermingled with single five-sided and four-sided
forms) ; their axial rod and its prolongation, the radial apical spine, three to four times as thick as
the slender edges of the pyramid. The distal end of the apical spine bears an elegant star of numerous
radially divergent terminal branches, each of which is armed with a spinulate terminal knob.

Dimensions. — Diameter of the sphere 3-5 to 4'0, length of the net bars 0'3, breadth 0'003 ;
length of the radial spines 0'2, breadth 0'012.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

2. Sagenoscena ornata, n. sp. (PI. 108, fig. 4).

Pyramids rather regular, usually six-sided (intermingled with single five-sided and seven-sided
forms); their axial rod and apical spine spindle-shaped, two to four times as thick as the smooth bars

1 Sagenoscena = Net with tents ; irttytiin,

REPORT ON THE RADIOLARIA. 1611

of the network. The distal end of the radial spines bears an elegant, foliate, terminal knob, com-
posed of four to six vertical pinnate leaves, lying in crossed meridional planes.

Dimensions. — Diameter of the sphere 2 to 3, length of the rods 01 to 0-2, breadth 0'003 to

o-oi.

Habitat. — Antarctic Ocean, Station 156, depth 1975 fathoms.

4

3. Sagenoscena penicillata, n. sp. (PL 108, fig. 10).

Pyramids rather regular, usually six-sided (intermingled with single five-sided, seven-sided, and
eight-sided forms) ; their axial rod and apical spine spindle-shaped, thicker than the smooth bars
of the network. The distal end of the radial spines is penicillate and bears a brush of bristle-
shaped, radial, terminal spinules (compare Sagosphcera penicilla, p. 1607).

Dimensions. — Diameter of the sphere 1 to 1'5, length of the bars O'l to 015, breadth 0'004 to
0-005.

Habitat. — Antarctic Ocean, Station 157, depth 1950 fathoms.

4. Sagenoscena coronata, n. sp.

Pyramids rather regular, usually four-sided (intermingled with single five-sided and six-sided
forms) ; their axial rod and apical spines cylindrical, scarcely thicker than the smooth bars of the
network. The distal end of the radial spines bears a corona of twenty to thirty curved terminal
branches, which form a regular circle, and are armed with a spinulate terminal knob.

Dimensions. — Diameter of the sphere 2 to 3, length of the bars 012 to 018, breadth 0'004 to
0-008.

Habitat. — North Pacific, Station 256, surface.

5. Sagenoscena spathillata, n. sp.

Pyramids more or less irregular, of different sizes and various forms, each composed of four to
eight convergent rods and a central axial rod. The latter is prolonged into a free apical spine,
which bears at the distal end a spathilla of eight to twelve recurved teeth, and often beyond it a
second similar verticil.

Dimensions. — Diameter of the sphere 4-0, length of the bars 01 to 0'2, breadth 0'002.

Habitat. — Arctic Ocean, Greenland (Olrik).

6. Sagenoscena cruciata, n. sp.

Pyramids very irregular, of different sizes and various forms, each composed of six to nine
convergent rods and a central axial rod. The latter is prolonged into a free apical spine, which
bears three to five cruciate verticils, each composed of four perpendicularly crossed lateral branches
which bear at the distal end a spinulate knob (similar to Sagmidium crucicorne, PI. 108, fig. 9).

Dimensions. — Diameter of the sphere TO to T2, length of the bars 0'06 to 0'09, breadth O'OOl.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

1612 THE VOYAGE OF H.M.S. CHALLENGER.

Subfamily 2. SAGMARIDA, Haeckel.

Definition, — S agosphserida with a spongy spherical shell, the thickened wall
of which is composed of a loose spongy framework.

i

Genus 679. Sagmarium, n. gen.

Definition. — S agosphserida with a spongy spherical shell, the thickened wall
of which is composed of a loose spongy framework, and exhibits a smooth surface,
without radial spines, and pyramidal elevations.

The genus Sagmarium, and the following two genera of Sagosphserida, represent
together the subfamily Sagmarida, differing from the preceding Sagenida in the spongy
structure of the shell-wall. Whilst in the latter the thin wall of the delicate spherical
shell is composed of a simple lattice-plate with triangular meshes, in the former numerous
branches diverge from the nodal points of these meshes, and produce by union an
irregular and loose spongy framework. The surface of this spongy hollow sphere
(similar to Plegmosphssra) is in Sagmarium smooth.

1. Sagmarium spongodictyum, n. sp. (PI. 108, fig. 2).

Spongy wall of the hollow sphere about half as thick as the radius of its cavity. Bars of the
spongy framework very thin and fragile, smooth, without thorns.

Dimensions. — Diameter of the sphere 2'0 to 2'4 ; length of the bars O'l to 0'2, breadth O'OOl.
Atlantic, Station 333, surface.

2. Sagmarium plegmosphcerium, n. sp. (PI. 108, fig. 14).

Spongy wall of the hollow sphere about one-fourth as thick as the radius of its cavity. Bars
of the spongy framework rather stout, studded with numerous small spines, which arise perpen-'
dicularly from their surface.

Dimensions. — Diameter of the sphere 1'2 to 1'5, length of the bars O'l to 016, breadth 0'004.

Habitat. — Tropical Atlantic, Station 347, surface.

3. Sagmarium trigonizon, Haeckel.

Didyosoma triyonizon, Haeckel, 1860, Monatsber. d. k. preuss. Akad. d. Wiss. Berlin, p. 841.
Spongodictyon trigonizon, Haeckel, 1862, Monogr. d. Eadiol., p. 459, Taf. xxvi. figs. 4, 5.

Bars of the spongy framework thin, irregularly curved, bearing scattered small crosses, which
are composed of four small rods arising perpendicularly from the bars. Nod.al points of the frame-

1 Sagmarium = Covering of a shield, armour ; <rxyftii%io!>.

REPORT ON THE RADIOLAR1A. 1613

work partly pierced by a hole. The peculiar network of a complete specimen, observed by me at
Portofino in 1880, was so similar to that of Spongodictyon trigonizon, described above (p. 91), and
figured in 1862 in my Monograph, that I am doubtful if the two forms are not identical, the two
medullary shells of the latter being accidentally entangled in the framework. (Compare p. 1602.)

Dimensions. — Diameter of the sphere I'l to 1*5, length of the bars 01 to 0'2, breadth 0'002.

Habitat. — Mediterranean (Messina, Portofino), surface.

Genus 680. Sagmidium,1 n. gen.

Definition. — S ago sphserida with a spongy spherical shell, the thickened wall of
which is composed of a loose spongy framework, and bears on the nodal points of its
surface radial spines.

The genus Sagmidium differs from the preceding Sagmarium in the development
of radial spines on the surface of the spongy hollow sphere. It bears therefore the same
relation to the latter as Sagosphcera does to Sagena, and may be derived either from
Sagmarium by the formation of radial spines, or from Sagosphcsra by development of
the spongy envelope.

1. Sagmidium unicorne, n. sp.

Eadial spines simple, straight, smooth, a single one at each nodal point of the surface of the
spongy sphere, bearing on its distal end a spinulate knob, or a bunch of numerous radial bristles.
(Similar to Sayenoscena pcnicillata, PI. 108, fig. 10.) Bars of the spongy framework smooth.

Dimensions. — Diameter of the sphere 3'0 to 3'5, length of the bars 0'15 to 0'2, breadth O'OOS
to 0-006.

Habitat. — Antarctic Ocean, Station 256, surface.

2. Sagmidium income, n. sp.

Eadial spines simple, smooth, usually three divergent united at each nodal point of the surface
(sometimes two or four instead of three). Each spine bears on its distal end three short divergent
conical teeth. (Similar to the terminal teeth of Sagoscena tentorium, PI. 108, fig. 6.) Bars of the
spongy framework smooth.

Dimensions. — Diameter of the sphere l-6 to 24, length of the bars 0'06 to Q-09, breadth O'OOl
to 0-002.

Habitat, — Central Pacific, Stations 263 to 268, surface.

3. Sagmidium crucicorne, n. sp. (PI. 108, fig. 9).

Eadial spines slender, verticillate, three or four divergent arising from each nodal point of the
surface. Each spine bears three to six cruciate verticils of lateral branches ; each verticil being

1 Sagmidium = Small armour, military cloak ; <?»•//* ftion.

1614 THE VOYAGE OF H.M.S. CHALLENGER.

composed of four crossed small branches with a spinulate terminal knob. Bars of the spongy
framework partly covered with similar verticils.

Dimensions. — Diameter of the sphere 2'0 to 3'0, length of the bars 0'2 to 0'3, breadth O002
to 0-003.

Habitat. — North Pacific, Stations 240 to 244, surface.

4. Sagmidium quadricorne, n. sp. (PI. 108, fig. 12).

Eadial spines stout, smooth, cylindrical, usually four divergent arising from each nodal point of
the surface (sometimes three, five, or six, instead of four). Each spine bears on its distal end a
club-shaped stellate knob. Bars of the spongy framework smooth.

Dimensions. — Diameter of the sphere 4'5, length of the bars 0'2 to 0'3, breadth 0'003 to 0'005.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

5. Sagmidium multicorne, n. sp.

Kadial spines slender, more or less curved, verticillate, in variable number (three to six)
divergent, arising from the nodal points of the surface. The spines as well as the bars of the
spongy framework are partly simple, partly covered with irregularly scattered cruciate verticils, very
similar to those of Sagmarium trigonizon (or Dictyosoma trigonizon), figured in my Monograph,
pi. xxvi. figs. 4, 5.

Dimensions. — Diameter of the sphere 5'0, length of the bars 0'2 to 0'3, breadth 0-003.

Habitat. — Indian Ocean, Cocos Islands (Rabbe), surface.

Genus 681. Sagoplegma,1 n. gen.

Definition. — S agosphserida with a spongy spherical shell, the thickened wall of
which is composed of a loose spongy framework, and bears on its surface numerous
pyramidal elevations.

The genus Sagoplegma differs from Sagmarium, its ancestral form, in the development
of pyramidal or tent-shaped elevations on the surface of the spongy hollow sphere. It
exhibits, therefore, the same relation to the latter as the similar Sagoscena bears to
Sagena. The wall of the spherical shell is in the two latter genera a thin simple lattice-
plate, in the former a thickened spongy framework.

1. Sagoplegma pyramidophora, n. sp.

Pyramids on the surface of the spongy sphere subregular, mostly tetrahedral, of nearly equal
size and similar form. The three edges of each pyramid are prolonged over its top into three

1 Sagoplegma = Armour of framework ; acc'/n,

REPORT ON THE RADIOLARIA. 1615

short, divergent, apical spines which are forked at the distal end. (Very similar to Sagoscena castra
and Sagoscena tcntorium, PI. 108, figs. 1, 6, probably derived from them, but differing in the
spongy structure of the thickened shell-wall, which is half as thick as the radius of its cavity.)

Dimensions. — Diameter of the sphere 2'0 to 2'5, length of the bars 015 to 0'2, breadth 0'002.

Habitat. — North Pacific, Stations 231 to 239, surface.

2. Sagoplegma scenophora (PL 108, fig. 13).

Pyramids on the surface of the spongy sphere irregular, with three to six sides, unequal in size
and different in form. The edges of each pyramid are prolonged over its top into three to six
divergent apical spines, which bear three to six cruciate verticils, each composed of four small,
crossed, lateral branches, armed with a spinulate knob at the distal end.

Dimensions. — Diameter of the sphere 3'0 to 3'5, length of the bars 0-25 to 0'35, breadth 0'003.

Habitat. — North Pacific, Stations 252, 253, surface.

Family LXXVI. AULOSPH^RIDA, Haeckel (Pis, 1 09- 111).

Aulosphcerida, Haeckel, 1862, Monogr. d. Radiol., p. 357.

Definition. — PELEODARIA with a large spherical or subspherical (rarely spindle-
shaped) articulated shell, which is composed of hollow tangential tubes. Nodal points
of the loose network stellate, with a nodal cavity and astral septa. Meshes either
triangular or polygonal. Hollow radial spines arise usually at the nodal points of the
surface. No peculiar mouth in the shell. Central capsule tripylean, placed in the centre
of the shell.

The family Aulosphaerida comprises a great number of splendid and widely distri-
buted PH^EODARIA, which have a special interest on account of the peculiarly complicated
structure of their large lattice-shell, of the extraordinary beauty of their form and of
their remarkable relations to the other PH^EODARIA. They differ from all the other
Radiolaria in the peculiar articulate composition of the spherical skeleton of hollow
tangential tubes, which are connected (and at the same time separated) by sutural or
astral septa and filled up by jelly. The same peculiar structure recurs only in the
closely allied Cannosphserida, which, however, differ in the possession of a second internal
concentric shell, connected with the outer by radial beams. The similar Sagosphserida,
which exhibit corresponding forms in various genera, differ from the Aulosphasrida in
the simpler structure of the delicate lattice-sphere, which is composed of very thin solid
threads of silica, without astral septa. The Orosphaerida, finally, also nearly related to
the preceding families, differ from them in the coarse structure of the lattice-sphere,
which is composed of very thick tangential, concentrically stratified rods, with an
internal axial canal, but without astral septa at the nodal points.

1616 THE VOYAGE OF H.M.S. CHALLENGER.

One genus only, and two species, of Aulosphserida have been hitherto known, having
been discovered by me in 1859 at Messina, and described in my Monograph in 1862
as Aulosphcera trigonopu and Aulosphcera elegantissima (loc. cit., p. 357, Taf. x. figs. 4, 5 ;
Taf. xi. figs. 5, 6). The characteristic structure of their central capsule, as true
TRIPYLEA, was afterwards, in 1879, described more accurately by Richard Hertwig
(Organism, d. Radiol., p. 90, Taf. x. figs. 2, 8, 14). The rich collection of the Challenger
has demonstrated that the Aulosphserida belong to the most common and most widely
distributed PH^EODARIA; many of them are distinguished by the admirable elegance and
astonishing regularity of their large and delicate shell. Nine genera and fifty-six species
of this great family are described in the following pages, which, however, may represent
only a small part of the numerous forms which are found on the surface as well as in
different depths of all oceans and in all zones.

The shell is in the great majority of Aulosphserida a regular sphere or an endospherical
polyhedron. Two genera only, both rather rare, exhibit a different monaxonial form, one
vertical main axis being developed either more or less than all the other ones of the
sphere : — Aulatractus is spindle-shaped or ellipsoidal, with prolonged main axis ;
Aulophacus is lenticular or discoidal, with shortened main axis. The former may be
compared to the Prunoidea, the latter to the Disco idea, in opposition to the
common regular Sphseroidea. The size of the lattice-shell is very considerable in all
Aulosphserida, its diameter varying usually between 1 and 3 mm., often it amounts
to 4 or 5 mm.; very rarely the diameter is more than 5 or less than 1 mm. The
largest form observed is the spindle-shaped Aulatractus, in which the vertical prolonged
main axis attains 6 to 10 mm., the horizontal equatorial axis 3 to 5 mm.

The network of the lattice-shell exhibits in the Aulosphserida two different types,
according to which we distinguish two different subfamilies : Aularida and Aulonida ;
the former are much more common and richer in remarkable forms than the latter. The
meshes of the network are in the Aularida constantly triangular, regular or subregular,
and very similar to those of the Sagosphaerida ; at each nodal point six tangential tubes
are usually united, so that the network may be regarded also as composed of regular
hexagonal meshes, each of which is divided into six smaller triangular meshes (PI. 109,
figs. 1, 3, 5). The second subfamily, the Aulonida, are much rarer than the former, and
are distinguished by the polygonal meshes of the network ; these are usually more or less
irregular, pentagonal and hexagonal intermingled, more rarely tetragonal, heptagonal, or
octagonal ; usually three or four, rarely five or more tangential tubes are united at each
nodal point (PI. Ill, figs. 1, 3). The size of the meshes is very considerable, and agrees
with that of the Sagosphserida ; their diameter being usually between O'l and 0'3, rarely
less or more.

The hollow tubes which compose the loose network are usually cylindrical, straight
or slightly curved, smooth (PI. Ill, fig. 2), more rarely somewhat spinulate (PI. 109,

REPORT ON THE RADIOLAEIA. 1617

fig. 5). Their length is usually between O'l and 0'2 mm., rarely less than 0'08, or more than
0'24 mm.; their diameter usually between 0'003 to 0'005, sometimes only 0'002 or less,
at other times O'OOG or more. In several species the tangential tubes are thinner in the
middle part, and thickened towards the two ends (PI. 109, figs. 3, 4). Each tube con-
sists of a thin cylindrical wall of silex, and of a jelly-mass filling up its cavity; in its
axis runs a very thin, straight or slightly curved thread of silica, the axial filament.

The arrangement of the tangential tubes, which originally, in the simplest
Aulosphserida, lie tangentially in the spherical face of a simple lattice-sphere, exhibits
various secondary modifications, leading to various interesting generic forms. Two
genera only, Attlaria (with triangular meshes, PI. Ill, fig. 2) and Aulonia (with
polygonal meshes, PI. Ill, fig. 1) possess a smooth, perfectly simple lattice-sphere, and
may therefore be regarded as the ancestral genera of the two subfamilies. Two other
corresponding genera, the common Aulosphcera (PI. 109) and the rarer Aulastrum
(PL 111, fig. 3), differ from the former in the development of radial spines at the nodal
points of the simple lattice-sphere. Aulophacus may be developed from Aulosphcera
by shortening, Aulatractus, however, by prolongation of the vertical main axis (PI. Ill,
figs. G, 7). In two genera, Auloplegma and Aulodictyum, the latticed wall of the spherical
shell becomes thickened and spongy, an irregular framework being formed by tubes
connected in different directions (PI. Ill, fig. 8). The most remarkable and the most
elegant form, however, of the whole family is represented by Auloscena (PI. 110).
The entire surface of the spherical lattice-shell is here covered with numerous regular or
subregular pyramids, or tent-shaped elevations. Usually each pyramid is six-sided, and
surrounded by six other six-sided pyramids, their bases being separated by six triangular
meshes, which lie in the spherical face. A similar elegant form is developed among the
Sagosphserida in the genera Sagoscena, Sagenoscena and Sagoplegma (PI. 108, fig. 1).
The structure of Auloscena, however, is usually more regular, and in the top of each
pyramid a radial tube arises.

The junction of the cylindrical tubes at the nodal points of the network is very
remarkable. Aularia, the simplest form of the family, exhibits at each nodal point the
union of six tangential tubes (PL 111, fig. 2) ; their ends are so pointed and truncated
that they are connected in the form of a regular six-radiate star ; the conical end of each
tube is separated from, and at the same time closely connected with, the adjacent conical
ends of the two neighbouring tubes by a thin septum, the astral or sutural septum. The
six astral septa compose together a six-radiate star, and in the centre of this star the six
axial filaments of the tubes are united. Their central union is surrounded by a small,
double-contoured circle, and this circle seems to be the perimeter of a small and flat
Cavity on the inside of the star, which we call shortly the " nodal cavity " (" die kleine
Vertiefung" according to Hertwig, loc. cit., p. 90). The nodal cavity of Aularia
probably possesses a central opening on its inside and six small surrounding pores, which

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 203

1618 THE VOYAGE OF H.M.S. CHALLENGER.

lead into the six connected tangential tubes. In Aulosphcera and Auloscena, where a
radial spine arises at each nodal point, its axial filament arises from the centre of the star,
and is usually prolonged on the inside into a free centripetal beam (PI. 109, figs. 6, 7;
PL 110, figs. 4, 6). This centripetal beam is a slender, very thin, conical tube (often
with a six-sided pyramidal base) and perhaps of great morphological interest as a rudiment,
being homologous to the hollow radial beams which connect the two concentric spheres of
the Cannospheerida. Possibly the Aulosphserida have been derived from the latter by loss
of the inner shell and reduction of the radial beams ; the centripetal beams which are found
in many (but not in all) Aulosphserida, may be the last remnant of those radial beams.
They contain also an axial filament, as a direct internal prolongation of that of the
external radial spine. The axial filaments of the radial spines are usually connected with
their thin wall by a variable number of scattered transverse threads, or sometimes even
by thin transverse septa (PI. 110, figs. 4-7, &c.). This structure corresponds to the
similar axial filaments and their thin filiform transverse branches which we have found in
other PR/EODARIA, e.g., in the Tuscarorida and Circoporida.

The Aulonida (with polygonal meshes) exhibit in general the same structure as the
Aularida (with triangular meshes). But whilst in the latter usually six tangential tubes
are united at each nodal point, in the former only three or four tubes become united.
Therefore also the number of the small sutural partitions or astral septa, which radiate
from the central openings of the nodal cavity, is six in the latter, three or four in the
former. Correspondingly three or four small pores lead from the nodal cavity into the
surrounding tangential tubes.

The true nature of the nodal points, and the intimate structure of the different parts
here united, is a matter which it is very difficult to explain. It is a certain fact, well
established by hundreds of observations, that in the complete and well-preserved skeletons
which are perfectly purified by fire, or by hot mineral acids, and afterwards dried, all the
tubes of the skeleton, the tangential as well as the radial cylinders, become filled up by
air. Each tube contains usually one large cylindrical air-bubble, with two hemispherical
ends. But the air-bubbles of the neighbouring tubes are completely separated one from
another by the thin astral or sutural septa, and the air-bubble of the radial tubes is also
separated from the former. The central cavity of each nodal point is therefore surrounded
in the Aularida by six, in the Aulonida by three or four separate cylinders of air. This
fact seems to be explained only on the supposition that each single tube has two terminal
pores or fissures, which open into the two nodal cavities on its two ends. The radial
tubes must also possess at least one small opening, probably on their base, and probably
they have another on their distal apex. In no other way can it be explained, that
in all complete, well-preserved and purified skeletons, each single tube constantly becomes
easily filled by an air-bubble after drying.

In the living Aulosphserida the cavities of all tubes are filled up by a jelly-substance,

REPORT ON THE RADIOLARIA. 1619

which may be stained by carmine and is probably identical with the jelly of the calymma.
The latter is probably in direct connection with the former by the central pore of the
nodal cavity, which is placed on its inside and surrounded by the astral septa ; these
separate the tangential tubes, radiating from one nodal point, completely, and are thin
and simple, but very solid lamellae of silica. Therefore the nodal stars of broken shells
usually remain united, whilst the single radiating tubes composing them are broken off
(PI. 110, figs. 3, 8, 10). But it happens only rarely (and only in certain individual species)
that complete single tubes separate; usually the fragments of the connected neighbouring
tubes remain on their ends. The two small terminal openings of each tangential tube,
which lead from its cavity into the nodal cavity, and are surrounded on each end by the
truncated ends of two neighbouring astral septa, are very difficult to observe (PL 110,
figs. 8-10).

The wonderful elegance and the high complication of these regular skeletons of
the Aulosphserida, produced by a single cell, becomes increased by the graceful and
manifold appendages and apophyses which are usually developed on the radial tubes.
In only a few species these are simple, as in the common and cosmopolitan Aulosphcera
trigonopa. Usually lateral or terminal appendages are developed in great variety, a
selection of which is figured in Pis. 109-111. The lateral branches are either
irregularly scattered spines (PL 110, figs. 3-7) or regular verticils of cruciate or radiate
spines ; each verticil is usually composed of four perpendicularly crossed horizontal
branches (PL 109, figs. 3, 4, 7, 10, &c.), more rarely of a greater number of radiating
transverse branches.

The terminal appendages of the radial spines exhibit a striking similarity with those
of the Aulacanthida (Pis. 102-105). They are either forks with two or three divergent
branches (PL 111, figs. 3, 4), or regular crosses with four branches opposite in pairs
(PL 109, figs. 2, 6, 7, 10), or elegant crowns or verticils, composed of numerous radiating
branches (PL 110, figs. 1-6). The distal ends of the terminal as well as of the lateral
branches are either simple, pointed, or armed with a spinulate knob, or with a terminal
spathilla. The variety and elegance of these terminal ornaments, the function of which
is that of capturing tentacles, is in the Aulosphserida not less admirable than in the
Aulacanthida and Coslodendrida.

The central capsule of the Aulosphserida (PL 111, fig. 2) was first figured in my
Monograph (1862, Taf. xi. fig. 5) of Aulosphcera elegantissima, as a sphere of 0'2 to 0'3
mm. in diameter. I described there the large nucleus (of half that size) as a spherical
"Binnenblase," and the numerous pseudopodia which arise from the capsule and radiate
through the meshes of the lattice-shell. But I had not observed at that time the three
typical openings of the capsule, which were first discovered and accurately described by
E. Hertwig (1879, loc. cit., p. 94, Taf. x. figs. 2, 4, 5, 8, 14). The large astropyle with
its radiate operculum and proboscis, and the two smaller lateral parapylse, provided with

1620

THE VOYAGE OF H.M.S. CHALLENGER.

a smaller tubule, have in general the same shape as in the closely allied Sagosphserida
-and Orosphserida, and agree in their strong development with that of the Aulacanthicla.
The collection of the Challenger contains numerous well-preserved preparations of
Aulosphserida, which were stained by carmine immediately after being captured, and in
which the central capsule and its nucleus exhibit the same intimate structure already
accurately described by R. Hertwig. The diameter of the capsule is usually between
0'2 and 0'3, rarely less than 0'15 or more than 0'35 mm., the nucleus has half that
size. The phseodium has usually about the same volume (PL 109, fig. 1), but seems
to be in many Aulosphserida less developed than in the other PH^EODAEIA.

I. Subfamily

Aularida.

Meshes of the net-
work triangular,
regular or sub-
regular. Six
tangential tubes
united at each
nodal point of the
net.

II. Subfamily

Aulonida.

Meshes of the net-
work polygonal,
usually irregular.
Three or four
(rarely more) tan-
gential tubes
united at each
nodal point.

Synopsis of the Genera of Aulosphcerida.

Without radial tubes,

Shell spherical, with a simple j
network.

Shell spherical, with pyra-
midal elevations or with
spongy framework.

Shell not spherical, either
lenticular orspindle-shaped,
with simple network.

Shell spherical, with a spongy
framework.

With radial tubes in the nodes of
the net,

Shell covered with pyramidal
elevations, the top of which
bears a radial tube,

Shell with spongy framework, the
surface of which bears radial
tubes, ....

(" Shell lenticular, with shortened
main axis and radial tubes,

indle.sh d with

r ' r

longed mam axis and radial
tubes, ....

Without radial tubes,

682. Aularia.

683. Aulosphcera.

684. Auloscena.

685. Auloplegma.

686. AulopJiacus.

687. Aulatradus.

688. Aulonia.

With radial tubes in the nodes of

the net, . . . 689. Aulastrum.

Aulodid

-^ ^.^ tub

Subfamily 1. AULARIDA, Haeckel.

Definition. — Network of the shell with triangular, regular or subregular meshes ;
six tangential tubes being united at each nodal point.

REPORT ON THE RADIOLARIA. 1621

Genus 682. Aularia,1 n. gen.

Definition. — A ulosphasrida with triangular meshes in the network, the
tangential tubes of which form a simple smooth lattice -sphere. No radial tubes at the
nodal points.

The genus Aularia is the simplest form of the subfamily Aularida, or of those
Aulosphserida in which the network of the shell is composed of regular or subregular
triangular meshes ; they are the main group of the family, much more common and far
richer in distinct forms than the Aulonida (or the Aulosphserida with polygonal
meshes). The shell of Aularia, the probable ancestral form of the family, is a simple
lattice-sphere with smooth surface, and differs from the common Aulosphcera in the
absence of radial tubes, arising at the nodal points.

1. Aularia ternaria, n. sp. (PL 111, fig. 2).

Tangential tubes of the network cylindrical, straight, smooth, of equal breadth. Triangular
meshes of the reticular sphere very regular, equilateral triangular. This species is the simplest of
all Aulosphserida and similar to the common AulospJwera (rigonopa, but has no radial tubos.

Dimensions. — Diameter of the sphere TO to 2'0 ; tubes 01 to 015 long, 0'007 to O'Ol broad.

Habitat. — Central Pacific, Stations 270 to 274, surface.

2. Aularia tubularia, n. sp.

Tangential tubes of the network cylindrical, straight, of equal breadth, thorny, covered with
numerous short bristle-shaped thorns, which are all of the same length and perpendicular to
the tube.

Dimensions. — Diameter of the sphere 3'0 ; tubes 015 long, O'OOS broad.

Habitat. — South Pacific, Station 291, depth 2250 fathoms.

3. Aularia trigonaria, n. sp.

Tangential tubes of the network smooth, very thin in the middle part, gradually dilated
towards both ends, so that the nodal points of the network are inflated. (Similar to Aulosphcera
sceptroplwra, PL 109, fig. 3, but without radial tubes.)

Dimensions. — Diameter of the sphere 2'2 ; tubes 01 long, 0'002 broad in the middle part,
O'Ol on both sides.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

1 A ularia = Tubular shell ;

1622 THE VOYAGE OF H.M.S. CHALLENGER.

X

Genus 683. Aulosphcera,1 Haeckel, 1860, Monatsber. d. k. preuss.
Akad. d. Wiss. Berlin, p. 802.

Definition. — A ulosphserida with triangular meshes in the network, the
tangential tubes of which form a simple lattice-sphere. Radial tubes arise at its nodal
points.

The genus Aulosphcera, the first observed form of all Aulosphserida, is also the
most common form of the whole family, the richest in distinct species, and widely
distributed over all oceans, in the tropical as well as in the temperate and Arctic zones.

The twenty-one species here enumerated may be only a small part of the numerous
forms, which may be distinguished according to the different forms of the tubes. One
of the two Mediterranean species, which I first described in my Monograph, is cos-
mopolitan. The shell is in all species a simple regular lattice -sphere with triangular
meshes ; it differs from the preceding Aularia in the development of radial tubes at
the nodal points of the lattice-work.

Subgenus 1. Aulosphcerantha, Haeckel.

• 9

Definition. — Radial tubes simple, smooth, without terminal teeth and without
lateral branches.

1. Aulosphcera trigonopa, Haeckel.

Aulosphcera trigonopa, Haeckel, 1862, Monogr. d. Radio]., p. 359, Taf. x. fig. 4.

Eadial tubes of the spherical shell cylindro-conical, straight, smooth, of the same length as the
tangential tubes of the network, which are also smooth, straight, cylindrical.

Dimensions. — Diameter of the sphere 1-0 to 2'0 ; tangential tubes 01 to 0'2 long, 0'002 to
0-004 broad.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, surface.

2. Aulosphcera flexuosa, n. sp.

Eadial tubes slenderly conical, smooth, gradually tapering towards the distal end, more or less
irregularly curved, two to three times as long as the tangential tubes, which are cylindrical,
straight and smooth.

Dimensions. — Diameter of the sphere 2'2 ; tangential tubes 015 long, 0'006 broad.

Habitat. — North Atlantic, Faroe Channel (Gulf Stream), John Murray, surface.

1 Aulosphtem = Tubular sphere ; afao;,

REPORT ON THE RADIOLARIA. 1623

Subgenus 2. Aulosphasrdla, Haeckel.

Definition. — Radial tubes smooth, without lateral branches or spines, but armed
with a verticil of teeth at the distal end.

3. Aulosphcera diodon, n. sp.

Eadial tubes cylindro-conical, straight, smooth, of the same length as the smooth, cylindrical,
tangential tubes ; armed at the distal end with two divergent terminal teeth, which are slightly
curved, pincer-shaped, and about one-fourth as long as the tube.

Dimensions. — Diameter of the sphere 2'5 ; tangential tubes 0'16 long, 0'003 broad.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Aulosphcera triodon, n. sp. (PL 109, fig. 8).

Radial tubes cylindrical, straight, smooth, two to three times as long as the smooth, cylindrical,
tangential tubes ; armed at the distal end with three divergent terminal teeth, which are straight
or slightly curved and about one-third as long as the tube.

Dimensions. — Diameter of the sphere 1'2 ; tangential tubes O'l long, O'Ol broad.

Habitat. — North-Eastern Pacific (off Japan), Station 231, surface.

5. Aulosphcera tetrodon, n. sp.

Eadial tubes slender, cylindrical, straight, smooth, about three times as long as the smooth,
cylindrical, tangential tubes ; armed at the distal end with a regular cross of four terminal teeth,
which are directed almost horizontally, and are slightly recurved (just as in Aulosphcera spathillata,
PI. 109, fig. 7, but longer and without lateral verticils).

Dimensions. — Diameter of the sphere 1'6 ; tangential tubes 015 long, O'OOS broad.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

6. Aulosphcera, polyodon, n. sp.

Eadial tubes slender, spindle-shaped, gradually tapering towards the two ends, smooth, about
twice as long as the cylindrical, smooth, tangential tubes ; armed at the distal end with a verticil
of twelve to twenty or more divergent, conical, slightly curved teeth.

Dimensions. — Diameter of the sphere 3'3 ; tangential tubes 0'2 long, O'Ol broad.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Subgenus 3. Aulosphcerissa, Haeckel.

Definition. — Radial tubes verticillate, armed with a variable number of regular
verticils of lateral branches.

1624 THE VOYAGE OF H.M.S. CHALLENGER.

7. Aulosphcsra verticillata, n. sp.

Radial tubes slender, cylindro- conical, straight, tapering towards the distal end, about as long as
the smooth, cylindrical, tangential tubes ; armed with eight to twelve verticils of three curved,
simple, lateral branches. (Very similar to the tubes of Aulastrum trickoceros, PL 111, fig. 5a.)

Dimensions. — Diameter of the sphere 1/6 ; tangential tubes 015 long, O'OOS broad.

Habitat. — South Pacific, Station 300, surface.

8. Aulosphcera spathillata, n. sp. (PI. 109, figs. 7, 7«).

Eadial tubes slender, cylindro-conical, straight, tapering towards the distal end, two to three
times as long as the smooth, cylindrical, tangential tubes ; armed with two or three distal alternate
verticils, each of which forms a horizontal cross of four (sometimes three or five) equidistant
branches ; their distal ends are on the terminal cross simple hooks, on the proximal cross spathillre.

Dimensions. — Diameter of the sphere 3'2 ; tangential tubes 012 to 016 long, O'Ol broad.

Habitat. —South-Eastern Pacific (off Valparaiso), Station 298, depth 2225 fathoms.

9. Aulosphcera cruciata, Haeckel (PI. 109, fig. 10).

Aulosphcera elegantissima, E. Hertwig (non Haeckel), 1879, Organism, d. Eadiol., p. 90, Taf. ix.

fig. 1; Taf. x. figs. 2,4, 5,8, 14, 15.
1 Aulosphcera pourtalesii, Duncan, 1881, Journ. Boy. Micr. Soc., p. 175, pi. iii. figs. 1-3.

Eadial tubes slender, cylindro-conical, straight, tapering towards the distal end, twice as long as
the smooth, cylindrical, tangential tubes ; armed with four to eight cruciate equidistant verticils,
each of which forms a regular cross of four equal, horizontal, lateral branches, bearing at the end a
small knob or spathilla.

Dimensions. — Diameter of the sphere 1/2 to 1/8 ; tangential tubes 01 to 015 long, O'OOS broad.

Habitat. — Mediterranean (Messina), North Atlantic (Canary Islands), Caribbean Sea.

10. Aulosphcera elegantissima, Haeckel.

AulospJicera elegantissima, Haeckel, 1862, Monogr. d. Eadiol., p. 359, Taf. x. fig. 5; Taf. xi.
figs. 5, 6.

Eadial tubes cylindrical, straight, twice as long as the smooth, cylindrical, tangential tubes ;
armed with four to eight equidistant verticils, each of which is composed of eight to twelve simple,
horizontal, lateral branches.

Dimensions. — Diameter of the sphere 1/5 to 2 ; tangential tubes 012 to 016 long, 0-004 broad.

Habitat. — Mediterranean (Messina), surface.

11. Aulosphcera bisternaria, n. sp. (PL 109, figs. 11, 12).

Eadial tubes cylindrical, straight, about as long as the cylindrical tangential tubes, smooth or
somewhat thorny, armed at the distal end with two alternate verticils of three branches, which bear

REPORT ON THE RADIOLARIA. 1625

a terminal spathilla ; the proximal branches are twice as long as the distal, and alternate with them
regularly, so that the six branches lie in six different meridional planes.

Dimensions. — Diameter of the sphere 2'5 ; tangential tubes 0'2 long, O'Ol broad.

Habitat. — Antarctic Ocean, Station 156, surface.

* 12. Aulosphcera dendr&phora, n. sp. (PI. 109, figs, l, 2).

Eadial tubes cylindrical, straight, about as long as the cylindrical, smooth, tangential tubes,
armed in the distal half with three verticils of four crossed branches ; the four proximal branches
are three times as long as the four distal, and twice as long as the four intermediate branches.
All twelve branches bear a terminal spinulate knob, and lie in two perpendicularly crossed
meridian planes.

Dimensions. — Diameter of the sphere 2'2 to 2'8 ; tangential tubes 0'2 long, O'Ol broad.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

13. AulosphcBra sceptrophora, n. sp. (PI. 109, figs. 3, 4).

Eadial tubes straight, in the proximal half conical, with inflated base ; in the distal half
cylindrical, with five or six cruciate verticils, each of which has four perpendicularly crossed teeth.
Tangential tubes half as long as the radial tubes, in the middle part very thin, thickened towards
both ends.

Dimensions. — Diameter of the sphere 1'2 ; tangential tubes O'l long, 0'002 broad in the middle
part, O'Ol 2 on both ends.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

14. Aulosplmra spathophora, n. sp.

Eadial tubes slender, cylindrical, more or less curved, about three times as long as the
tangential tubes, in the distal half with eight to twelve verticils of six to eight lateral branches,
which are forked, decrease in length towards the distal end, and bear on each ramule a terminal
spathilla. Tangential tubes slightly curved and thorny. (Similar to Auloplegma perplexum,
PI. Ill, fig. S«, but with a simple lattice-sphere.)

Dimensions. — Diameter of the sphere 2'2 ; tangential tubes 0'2 long, O'OOC broad.

Habitat. — Xorth Pacific, Station 244, depth 2900 fathoms.

Subgenus 4. Aulosphceromma, Haeckel.

Definition. — Radial tubes spiny or thorny, with irregular lateral branches, often
with forked distal ends.

(ZOOL. CHALL. EXP. — PART. XL. — 1886.) Rr 204

1626 THE VOYAGE OF H.M.S. CHALLENGER.

15. Aulosphcera bifurca, n. sp.

Eadial tubes cylindrical, straight, thorny, twice as long as the smooth, cylindrical, tangential
tubes, forked at the distal end, with two curved, convergent, thorny, terminal branches. (Similar
to Aulastrum dendroceros, PI. Ill, figs. 4a-4c, but with longer and more spinulate branches.)

Dimensions. — Diameter of the sphere 3'2 ; tangential tubes 0'25 long, O'Ol broad.

Habitat. — North Pacific, Station 239, surface. «

16. Aulosphcera trifurca, n. sp. (PI. 109, fig. 9).

Eadial tubes cylindrical, straight, thorny, about as long as the smooth, cylindrical, tangential
tubes, forked at the distal end, with three curved, convergent, terminal branches.

Dimensions. — Diameter of the sphere 2'5 to 3'0 ; tangential tubes 0'2 long, O'Ol broad.
Habitat. — North Pacific, Station 240, surface.

17. Aulosphcera quadrifurca, n. sp.

Eadial tubes cylindro-conical, straight, about as long as the smooth, cylindrical, tangential tubes ;
studded with numerous irregular lateral branches in the distal half, and armed at the distal end
with a cross of four divergent, forked, terminal branches.

Dimensions. — Diameter of the sphere 4'2 ; tangential tubes 0'2 long, O'Ol broad.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

18. Aulosphcera multifurca, n. sp.

Eadial tubes cylindrical, more or less curved, three to four times as long as the smooth, often
curved, tangential tubes ; studded with numerous forked, irregular, lateral branches, and armed at
the distal end with a verticil of twelve to sixteen divergent, forked, terminal branches.

Dimensions. — Diameter of the sphere 1-2 ; tangential tubes 0'06 long, 0'003 broad.

Habitat. — Arctic Ocean, Greenland (Olrik), surface.

19. Aulosphazra coronata, n. sp.

Eadial tubes spindle-shaped, tapering from the thicker middle pajf; towards both ends, twice as
long as the thorny tangential tubes, studded with numerous irregular, curved, lateral spines, and bearing
at the distal end a corona of twenty to twenty-five divergent, curved, terminal branches. (Similar to
Auloscena flammabunda, PL 110, fig. 4.)

Dimensions. — Diameter of the sphere 3D ; tangential tubes 0-2 long, 0'08 broad.

Habitat. — Tropical Atlantic, Station 347, surface.

REPORT ON THE RADIOLARIA. 1627

20. Aulosphcera undulata, n. sp. (PL 109, fig. 6).

Eadial tubes slender, cylindro-conical, undulate, about twice as long as the spinulate and
undulate tangential tubes; studded with numerous short, perpendicular, lateral branches which are
partly simple, partly forked, and bear small terminal spathillse. The distal end of each radial tube
bears usually a verticil of four to eight similar pediculate spathillae.

Dimensions. — Diameter of the sphere 2'4; tangential tubes 0'2 long, 0'005 broad.

Habitat. — North Pacific, Station 252, surface.
/

21. Aulosphcera spinosa, n. sp. (PI. 109, fig. 5).

Eadial tubes and tangential tubes equal in size and similar in form, more or less curved, slender,
cylindrical, densely studded with numerous irregular spines.

Dimensions. —--Diameter of the sphere l-6 ; tangential tubes O'l long, 0'004 broad.
Habitat.— Central Pacific, Station 271, depth 2425 fathoms.

Genus 684. Auloscena,1 n. gen.

Definition. — A ulosphserida with triangular meshes in the network, the tangential
tubes of which arise in pyramidal groups of six over the surface of the spherical shell.
Radial tubes arise at the tops of the six-sided pyramids, which cover the whole
surface.

The genus Auloscena differs from the preceding Aulosphara, its ancestral form, in
a very remarkable and elegant character. The tangential tubes of the network here lie
not on a spherical face (as in the latter), but arise over the surface of the spherical
calymma in the form of numerous, regular, hexagonal pyramids ; each pyramid being com-
posed of six convergent ascending tubes, which are united in a common nodal point; at
the latter arises a radial tube, which usually bears an elegant corona of radially divergent
terminal branches. Therefore the base of each hexagonal pyramid is in contact at its
six corners with the basal corners of six similar neighbouring pyramids, whilst the
neighbouring sides of the bases are separated by six regular triangular meshes, which
lie on the spherical face. In some species this remarkable and elegant structure is
quite regular, whilst in others it becomes more or less irregular.

Subgenus 1. Auloscenium, Haeckel.

Definition. — Radial tubes smooth, without lateral branches or spines, bearing a
terminal verticil at the distal end.

1 Aulascma = Tubular tent ; «.v*.i;, <rx»»ii.

1628 THE VOYAGE OF H.M.S. CHALLENGER.

1. Auloscena mirabilis, n. sp. (PL 110, figs. 1, 2).

Radial tubes cylindrical, straight, smooth, about as long as the smooth pyramidal tubes (or the
convergent tubes which form the edges of the six-sided pyramids of the network). The distal end
of each radial tube bears an elegant spathillate terminal corona (fig. 2), or a verticil of fifteen to
twenty curved radial branches, the distal end of which is armed with a spinulate knob.

Dimensions. — Diameter of the sphere 2'0 to 3'0; pyramidal tubes 0'16 to 0'24 long, O'OOS broad.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

2. Auloscena spectabilis, n. sp. (PI. 110, figs. 8, 9).

Radial tubes cylindro-conical, straight, smooth, twice as long as the smooth pyramidal tubes,
armed at the distal end with a conical terminal corona, or a verticil of twelve to sixteen divergent,
straight, pointed, terminal branches.

Dimensions. — Diameter of the sphere 4-0 to 5'0 ; pyramidal tubes 0'25 to 0'3 long, 0'012 broad.

Habitat. — Antarctic Ocean, Station 154, surface.

3. Auloscena pyramidalis, n. sp.

Radial tubes slender, conical, straight, smooth, of the same length as the smooth pyramidal
tubes, armed at the distal end with a hexagonal terminal corona, or a verticil of six divergent,
straight, pointed, terminal branches, which correspond to the six sides of a pyramid ; the proximal
apex of this terminal pyramid is opposed to the distal apex of the similar basal pyramid.

Dimensions. — Diameter of the sphere 3'0 to 4'0 ; pyramidal tubes 0'2 to 0'3 long, O'Ol broad.

Habitat. — Tropical Atlantic, Stations 347 to 349, surface.

Subgenus 2. Auloscenidium, Haeckel.

Definition. — Radial tubes thorny, with lateral branches or spines, usually with a
terminal verticil at the distal end.

4. Auloscena tentorium, n. sp. (PI. 110, fig. 6).

Radial tubes spindle-shaped, tapering towards both ends, nearly smooth, of the same length as
the smooth pyramidal tubes. The distal part of the radial tubes is thorny, and bears a verticil or
a corona of twenty to thirty slender terminal branches, which are about one-third as long as the
tube, sabre-shaped, with concave outer edge and pointed distal end.

Dimensions. — Diameter of the sphere 4'0 ; radial tubes 0'3 to 0'4 long, 0'02 to 0'03 broad.

Habitat. — North-Western Pacific (off Japan), Station 231, surface.

REPORT ON THE RADIOLARIA. 1629

5. Aidoscena verticillus, n. sp. (PI. 110, figs. 10, 11).

Eadial tubes slender, cylindrical, twice as long as the smooth or somewhat thorny pyramidal
tubes, armed in the distal part with two or three irregular verticils of three to six perpendicular
spines, and on the distal end with a corona of twelve to eighteen straight, divergent, pointed,
terminal branches, which often arise in pairs.

Dimensions. — Diameter of the sphere 3'2 ; pyramidal tubes 015 long, O'Ol broad.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

6. Aidoscena penicillus, n. sp. (PI. 110, fig. 3).

Eadial tubes slender, cylindrical, thorny, one and a half times as long as the thin and smooth
pyramidal tubes, armed in the distal half with densely crowded perpendicular spines and a terminal
corona of numerous (twenty to thirty or more) bristle-shaped branches, like a brush.

Dimensions. — Diameter of the sphere 2'0 to 2'5 ; radial tubes 015 to 0'2 long, 0'005 to O'Ol
broad.

Habitat. — Antarctic Ocean, Stations 156, 157, surface.

7. Aidoscena flammdbunda, n. sp. (PI. 110, fig. 4).

Eadial tubes cylindro-conical, twice as long as the thorny pyramidal tubes, studded with
numerous curved spines, and armed with a verticil or corona of numerous (twenty to thirty or more)
undulate, divergent, pointed, terminal branches.

Dimensions. — Diameter of the sphere 3'0 ; radial tubes 0'3 to 0'4 long, 0'02 to 0'03 broad.

Habitat. — North Pacific, Station 252, surface.

8. Auloscena gigantea, n. sp. (PL 110, fig. 7).

Eadial tubes cylindrical, thorny, about as long as the thorny pyramidal tubes, armed in the
distal half with four to eight verticils of short curved cilite, and at the distal end with a similar
small terminal verticil.

Dimensions. — Diameter of the sphere 5'2 ; pyramidal tubes 0'2 to 0'3 long, O'Ol broad.

Habitat. — Central Pacific, Stations 265 to 268, surface.

9. Auloscena arboretum, n. sp.

*

Eadial tubes cylindrical, straight or slightly curved, about the same length as the smooth
pyramidal tubes ; armed in the distal half with three or four verticils, tapering in size towards the
distal end ; each verticil is composed of four crossed and curved branches, which bear a terminal
spinulate knob. (This species is very similar to Aulosphccra deiulrophora, PI. 109, fig. 1, and may

1630 THE VOYAGE OF H.M.S. CHALLENGER.

be derived from it by elevation of the hexagonal pyramids, which in the latter lie in the spherical
plane).

Dimensions. — Diameter of the sphere 4'4 ; pyramidal tubes 0'25 long, O'Ol broad.

Habitat. — Indian Ocean, Cocos Islands (Rabbe), surface.

10. Auloscena serrata, n. sp. (PI. 110, fig. 5).

Radial tubes spindle-shaped, tapering towards both ends, thorny, twice as long as the thorny
pyramidal tubes ; armed at the distal end with an elegant corona which is composed of twelve to
sixteen curved terminal branches, Each branch bears two opposite series of small recurved teeth
and a terminal spathilla of six to eight larger recurved teeth.

Dimensions. — Diameter of the sphere 3'0 ; pyramidal tubes 0'3 long, O012 broad.

Habitat. — South Pacific, Station 298, depth 2225 fathoms.

Genus 685. Aulopleyma,1 Haeckel, 1879, Sitzungsb. med.-nat, Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — A ulosphserida with triangular meshes in the network, the tubes
of which are connected in different directions, and form the spongy wall of a
spherical shell. Radial tubes arise on the surface at the nodal points.

The genus Auloplegma, one of the rarest forms of Aulosphserida, differs from the
preceding genera in the spongy structure of the lattice -sphere, the thickened wall of
which is composed of a loose framework. Numerous tubes, irregularly disposed in
different directions, are connected at the nodal points of this loose spongy framework,
whilst radial tubes arise on the surface of the latter. Auloplegma exhibits therefore a
relation to Aulosphcera, its probable ancestral form, similar to that which Pleymosphcera
does to Acanthosphcera among the Sphseroidea.

1. Auloplegma perplexum, n. sp. (PL 111, figs. 8, 8a).

Radial tubes straight, cylindro-conical, armed with six to eight verticils of lateral branches,
which increase in size towards the base ; each verticil is a cross of four dichotomous delicate
ramules, ending with a spinulate knob. The length of the radial tubes is about equal to the radial
diameter of the spongy framework, which forms the thick wall of the spherical shell, and is
composed of smooth and straight cylindrical tubes.

Dimensions. — Diameter of the shell 1'5 to 2'0, of ifs wall 0'3 to 0'4 ; length of the radial tubes
0-2 to 0-3, basal breadth O015.

Habitat. — North Pacific, Station 237, surface.

1 A ulopleyma = Tubular framework ; <tixo'{,

REPORT ON THE RADIOLARIA. 1631

2. Auloplegma spongiosum, n. sp. (PI. Ill, fig. 9).

Radial tubes slender, straight, cylindro-conical, studded irregularly with lateral branches, which
are short, simple, slightly curved, partly verticillate in the distal third, and ending with a small
spinulate knob. The length of the radial tubes is about twice as great as the radial diameter of the
spongy framework, which forms the wall of the spherical shell, and is composed of thorny or verti-
cillate cylindrical tubes.

Dimensions. — Diameter of the shell 3'2, of its wall O'l ; length of the radial tubes 0'24,
breadth O'Ol.

Habitat. — North Pacific, Station 231, surface.

Genus 686. Aulophacus,1 n. gen.

Definition. — A ulosphserida with triangular meshes in the network, the
tangential tubes of which form a simple, lenticular, biconvex lattice-shell, with
shortened vertical main axis. Radial tubes arise at its nodal points.

The genus Aulophacus differs from the common Aulosphcera, its ancestral form,
only in the lenticular compression of the spherical lattice-shell, the vertical axis of
which is considerably shortened. It exhibits therefore to the latter the same relation
as Cenodiscus does to Cenosphcera among the Sphseroidea. The contrary condi-
tion is shown in the following genus Aulatractus, in which the vertical axis is prolonged.
In the two species of Aulophacus observed the radial spines exhibit a remarkable
peculiarity, being longer on the circular periphery of the lens, shorter on both its faces,
and shortest in the vertical main axis.

1. Aulophacus lenticularis, n. sp. (PI. Ill, fig. 5o).

Shell biconvex, lenticular, with rounded circular margin ; its horizontal diameter three times
as great as its thickness (or its vertical main axis). Radial tubes cylindro-conical, straight, with
six to nine triradiate verticils, those of the margin of the lens twice as long as the smooth tangential
tubes, the others shorter.

Dimensions. — Horizontal diameter of the lens 5'5 mm., vertical main axis 0'2 ; length of the
radial tubes 0'2, breadth O'Ol.

Habitat. — Indian Ocean, Belligemma, Ceylon (Haeckel) surface.

2. Aulophacus amphidiscus, n. sp. (PI. Ill, fig. 56).

Shell discoidal, slightly biconvex, with rounded circular margin ; its horizontal diameter five
times as great as its thickness. Radial tubes cylindrical, covered with numerous short thorns, those
of the margin of the lens three times as long as the smooth tangential tubes, the others shorter.

1 Aulophacus = Tubular lens ; <*iXo;,

1632 THE VOYAGE OF H.M.S. CHALLENGER.

Dimensions. — Horizontal diameter of the lens 6'0, vertical main axis T2 ; length of the radial
tubes 0-2, breadth 0'005.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

Genus 687. Aulatractus,1 n. gen.

Definition. — Aulos ph serid a with triangular meshes in the network, the
tangential tubes of which form an ellipsoidal or spindle-shaped, simple lattice-shell, with
prolonged vertical main axis. Radial tubes arise at its nodal points.

The genus Aulatractus differs from all the other Aulosphaerida in the peculiar
prolongation of the vertical axis of the lattice-sphere, by which the latter becomes
ellipsoidal or spindle-shaped. The triangular meshes of the regular lattice-work become
usually more or less irregular and polygonal at the two poles of the elongated main
axis. Aulatractus seems to be developed from Aulosphcera in the opposite way from
Aulophacus, the former by elongating, the latter by shortening of the vertical main-axis.

1. Aulatractus fusiformis, n. sp. (PI. Ill, figs. 6, 6a, 6b).

Shell spindle-shaped, about twice as long as broad, rounded at both poles of the main axis.
Tangential tubes smooth, cylindrical. Eadial tubes of the same length as the tangential tubes, but
much thinner, slender cylindrical, studded with perpendicularly arising, short, lateral branches, which
are scattered in the proximal part, verticillate in the distal part, and bear a spinulate terminal knob.

Dimensions. — Length of the shell 7'5 to 10-0, breadth 3'5; length of the radial tubes 015 to 018,
breadth O004.

Habitat. — Tropical Atlantic, Stations 348, 349 ; surface, and in various depths.

2. Aulatractus diploconus, n. sp. (PI. Ill, fig. 7).

Shell diploconical or nearly spindle-shaped, about three times as long as broad, equally pointed
at the two poles of the main axis, not inflated in the middle part. Eadial tubes slenderly conical,
thorny, only half as long as the smooth tangential tubes.

Dimensions. — Length of the shell 6'0 to 8'0, breadth 2'2 to 4'5 ; length of the radial tubes 01
to 015, breadth 0'007.

Habitat. — North Atlantic, Canary Islands, Station 353, surface.

3. Aulatractus fusulus, n. sp.

Shell spindle-shaped, about twice as long as broad, pointed at the two equal poles of the main
axis. Eadial tubes cylindro-conical, smooth, about as long as the smooth tangential tubes. This

1 A ulatractus = Spindle composed of tubes; aiAo'f, «ZTJ«*TO;.

REPORT ON THE RADIOLARIA. 1633

species resembles in its simple structure the common cosmopolitan Aulosphccra triyonopa, and differs
from it only in the constant spindle-form of the shell.

Dimensions. — Length of the shell 6 to 8, breadth 3 to 4 ; length of the radial tubes 016 to 0'2,
breadth 0-008.

Habitat. — North Atlantic, Fteroe Channel, Gulf Stream (John Murray) ; Hebrides (Mrebius).

4. Aulatractus ellipsoides, n. sp.

Shell ellipsoidal, about twice as long as broad, with equally rounded poles on the main axis.
Radial tubes straight, cylindrical, verticillate, about twice as long as the smooth tangential bars ;
each verticil is cruciate, composed of four rectangularly crossed, short, lateral branches which bear a
small spathilla at the distal end.

Dimensions. — Length of the shell 6'6, breadth 3-6 ; length of the radial tubes 0'2, breadth O'Ol.

Habitat. — South Atlantic, Station 332, surface.

Subfamily 2. AULONIDA, Haeckel.

Definition. — Network of the shell with polygonal, usually irregular meshes ; three
or four tangential tubes usually being united at each nodal point.

Genus 688. Aulonia,1 n. gen.

Definition. — Aulosph ser ida with polygonal meshes in the network, the
tangential tubes of which form a simple smooth lattice-sphere. No radial tubes at the
nodal points.

The genus Aulonia is the simplest form of the subfamily Aulonida, or of those
Aulosphserida in which the lattice-work of the shell is composed not of triangular but
of polygonal meshes ; all these Aulonida are much rarer and much less differentiated
than the Aularida or the common Aulosphserida with triangular meshes. Aulonia has
the same simple, smooth, spherical lattice-shell as Aulana, and differs from it only in
the polygonal form of the meshes, which, however, is very constant.

1. Aulonia tetragonia, n. sp.

Meshes regular or subregular, square, sometimes intermingled with a variable number of irregular,
triangular, and pentagonal meshes. Bars cylindrical, of equal breadth.

Dimensions. — Diameter of the spherical shell 2'0 to 3'2, of the meshes 012 to 018 ; breadth of
the bars O'OOS.

Habitat. — Antarctic Ocean, Station 154, depth 1800 fathoms.

1 Aulonia = Tubular object; afaoc, uilo».

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 205

1634 THE VOYAGE OF H.M.S. CHALLENGER.

2. Aulonia pentagonia, n. sp.

Meshes subregular, pentagonal, intermingled with a smaller number of quadrangular and
triangular irregular meshes. Bars cylindrical, of equal breadth.

Dimensions. — Diameter of the spherical shell 2-8 to 3'2, of the meshes 015 to 0'2 ; breadth of
the bars O'Ol.

Habitat. — South Pacific, Stations 293 to 302, depth 1375 to 2270 fathoms.

3. Aulonia hexagonia, n. sp. (PL 111, fig. 1).

Meshes regular or subregular, hexagonal, often intermingled with a variable number of
pentagonal and heptagonal meshes. Bars cylindrical, of equal breadth.

Dimensions. — Diameter of the spherical shell 2'5 to 3'3, of the meshes 015 to 0'25; breadth of
the bars 0-012.

Habitat. — Tropical Atlantic, Stations 347 to 349, surface.

4. Aulonia metagonia, n. sp.

Meshes subregularly alternating, larger octagonal and smaller tetragonal. The network of this
remarkable species has a striking similarity to the arrangement of the radial tubes in some species
of Sycon, figured in my Monograph of the Calcispongire (1872-, Bd. iii., Taf Ix. fig. 12).

Dimensions. — Diameter of the sphere 4'4, of the greater octagonal meshes 0'24 to 0'3, smaller
tetragonal 01 to 012 ; breadth of the bars 0'007.

Habitat. — Indian Ocean, Cocos Islands (Rabbe), surface.

5. Aulonia polygonia, n. sp.

Meshes irregular, polygonal, variable in form and unequal in size ; the majority u; ually pentagonal
or hexagonal, but numerous intermingled meshes with three, four; seven, or eight sides. Very
variable in the size of the bars and the form of the meshes.

Dimensions. —Diameter of the sphere 2'5 to 5'5, of the meshes 01 to 0-2 ; breadth of the bars
0-008 to 0-12.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, surface.

Genus 689. Aulastrum,1 n. gen.

Definition. — A ulosphserida with polygonal meshes in the network, the
tangential tubes of which form a simple lattice -sphere. Radial tubes arise at its
nodal points.

1 Aulai'rus = Tubular star ; avht

REPORT ON THE RADIOLARIA. 1635

The genus Aulastrum differs from the preceding Aulonia, its ancestral form, only
in the development of radial spines at the nodal points of the simple lattice-sphere.
It exhibits therefore to the latter the same relation as Aulosphcera does to Aularia.
But the meshes of the spherical network are constantly triangular in the two latter
genera, polygonal in the two former. The different species of Aulastrum are much
rarer, and are not so differentiated as those of the common Aulosphcera.

1. Aulastrum monoceros, n. sp.

Eadial tubes simple, smooth, straight, cylindro-conical, about as long as the smooth tangential
tubes or somewhat longer. Meshes of the network irregularly polygonal, the majority usually
pentagonal or hexagonal.

Dimensions. — Diameter of the sphere 3-0 to 4'0, of the meshes 015 ; breadth of the tubes
0-012.

Habitat. — Tropical Atlantic, Stations 347, 348, depth 2250 to 2450 fathoms.

2. Aulastrum dichoceros, n. sp.

Eadial tubes cylindrical, more or less curved, undulate, smooth, twice as long as the smooth
tangential tubes, forked at the distal end, with two divergent curved branches. Meshes of the net-
work subregular, hexagonal (as in Aulonia hexagonia, PI. Ill, fig. 1), intermingled with single
pentagonal and square meshes.

Dimensions. — Diameter of the sphere 2'0 to 2'5, of the meshes 012 to 018 ; breadth of the
tubes 0-01.

Habitat. — Antarctic Ocean, Station 157, depth 1950 fathoms.

3. Aulastrum dendroceros, n. sp. (PI. Ill, figs. 4a, b, c).

Eadial tubes cylindrical, straight or slightly curved, thorny, forked at the distal end, two to
three times as long as the thorny tangential tubes ; the thorns are short and thin, partly simple,
partly irregularly branched and scattered, arborescent. Meshes of the network irregularly
polygonal, the majority pentagonal or tetragonal.

Dimensions. — Diameter of the sphere 2'4 ; radial tubes 0'2 to 0'3 long, 0'02 broad.

Habitat. — North Pacific, Station 241 to 244, surface.

4. Aulastrum triceros, n. sp. (PI. Ill,, figs. 3, 3a).

Eadial tubes cylindrical, straight, smooth, about twice as long as the smooth tangential tubes,
armed with three divergent curved teeth at the distal end. Meshes subregular, pentagonal, inter-
mingled with a small number of tetragonal and hexagonal meshes.

Dimensions. — Diameter of the sphere T2 to 1-8 ; radial tubes 015 long, O'Ol broad.

Habitat. — Tropical Atlantic, Station 349, depth 2450 fathoms.

1636 THE VOYAGE OF H.M.S. CHALLENGER.

5. Aulastrum trichoceros, n. sp.

Eadial tubes slender, straight, cylindro-conical, about twice as long as the smooth tangential
tubes, armed with six to eight verticils of lateral branches, each of which is composed of three
short curved branches (similar to those of Aulophacus lenticularis, PI. Ill, fig. 5«). Meshes irregularly
polygonal, the majority tetragonal, intermingled with pentagonal and triangular meshes.

Dimensions. — Diameter of the sphere 2'2 ; tangential tubes 012 long, O'OOV broad.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

6. Aulastrum tetraceros, n. sp.

Eadial tubes straight, cylindrical, about three times as long as the smooth tangential meshes,
armed with three to six subregular cruciate verticils of branches, each of which is composed of four
short, regularly crossed branches, bearing at the end a spinulate knob (similar to those of
Aulatractus fusiformis, PI. Ill, fig. 6&). Meshes subregular, square, intermingled with single
pentagonal and hexagonal meshes.

Dimensions. — Diameter of the sphere T5, of the meshes 012 to 016 ; breadth of the bars
0-008.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

7. Aulastrum pentaceros, n. sp.

Eadial tubes straight, cylindrical, smooth, about as long as the smooth tangential tubes, armed
at the distal end with a corona of five curved teeth (of the same shape as in Ccmnospliacra
atlantica, PI. 112, fig. 6). Meshes subregular pentagonal (intermingled \ ith single tetragonal,
hexagonal, and heptagonal meshes).

Dimensions. — Diameter of the sphere 5'0, of the meshes 0'2 ; breadth of the bars 0'015.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

8. Aulastrum polyceros, n. sp.

Eadial tubes spindle-shaped, tapering from the broader middle towards both ends, spiny, twice
as long as the spiny tangential tubes, armed at the distal end with a corona of twelve to twenty
divergent curved teeth (similar to the radial tubes of Auloscena tentorium, PL 110, fig. 6).
Meshes irregular, polygonal, very variable in size and form. All tubes of this species are armed with
scattered, short, conical spines.

Dimensions. — Diameter of the sphere 4'5, of the meshes 01 to 0'2 ; breadth of the bars O'OOG.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

REPORT ON THE RADIOLARIA. 1637

Genus 690. Aidodictyum,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena,

Dec. 12, p. 6.

Definition. — A ulosphserida with polygonal meshes in the network, the tubes
of which are connected in different directions and form the spongy wall of a spherical
shell. No radial tubes prominent over the surface.

The genus Aulodictyum differs from Aulonia, its ancestral form, in the develop-
ment of a spongy framework in the thickened wall of the spherical lattice-shell. It
bears therefore to the latter the same relation as Auloplegma does to Aularia. But
the outer surface of the hollow sphere is in Aulodictyum completely smooth, as well as
the inner, and bears no radial tubes. Only one species of this genus has been observed.

1. Aulodictyum hydrodictyum, n. sp.

Shell spherical, smooth on the outer and inner surfaces, composed of an irregular framework of
straight and smooth cylindrical tubes ; its meshes very irregular, of unequal size and various forms.
The diameter of the sphere is about six or eight times as great as the thickness of its reticular
wall.

Dimensions. — Diameter of the sphere 2 to 3, of its meshes 01 to 0'2 ; breadth of the bars
O'Ol.

Habitat. — Antarctic Ocean, Station 157, depth 1950 fathoms.

Family LXXYII. CANNOSPH^RIDA, Haeckel (PL 1 1 2).

Cannosplicerida, Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12, p. G.

Definition. — PH^ODARIA with two concentric spherical or subspherical shells, which
are connected by numerous thin, tubular, radial beams. Inner shell simple, spherical or
ovate, solid or latticed, with a peculiar mouth. Outer shell spherical or polyhedral,
articulate, composed of hollow tangential tubes, which are separated by astral septa at
the stellate nodal points. From the latter arise hollow radial tubes, whilst the inner
radial beams, connecting the two shells, are inserted in the middle of the tangential tubes.
No peculiar mouth in the outer shell. Central capsule enclosed by the inner shell.

The family Cannosphserida comprises a small number of remarkable PH.EODARIA
which are rare and found only in a few localities. They differ from all the other
PH.EODARIA in the possession of two concentric spherical shells, which are connected by
radial beams, and the inner of which is quite simple, like that of the Medusettida,

1 Aulodictyum = T\i\m\a.r net ; «ixo',-|

1638 THE VOYAGE OF H.M.S. CHALLENGER.

whilst the outer is articulated and composed of hollow tangential tubes, like that of the
Aulosphserida. This latter family seems to be most nearly allied to the Cannospheerida,
and is perhaps derived from them by loss of the inner shell. The possession of a peculiar
mouth in this inner shell brings the Canuosphserida nearer to the Phseogromia. The
similar Ccelodrymida, in which also two concentric sphserical shells are connected by
hollow radial beams, differ essentially in the bivalved shape of the inner shell and the
simple, non-articulated, network of the outer shell.

Only a single species of Cannosphserida has been hitherto known, described and
figured in 1879 by E. Hertwig as Ccelacantha anchorata (loc. cit., p. 92, Taf. ix. fig. 2).
The rich collection of the Challenger has added to it only four other species, one of
which is most nearly allied to the former, whilst the others belong to a separate genus,
Cannosphcera (PI. 112). The inner shell is in this latter genus a solid lamella of
silica, whilst in the former it is fenestrated. In all other essential points of structure
both genera are scarcely different.

The inner shell is either spherical or ovate and has a diameter of O'l to 0'4 (usually
0'2 to 0'3 mm.). A distinct main axis is always marked by the large open mouth on
its oral pole. The aboral part of the shell-cavity contains the spherical central capsule,
the oral part the dark phaeodium, a part of which is often prominent through the
mouth (figs. 1, 2, 4). The wall of the inner shell is a very thin and transparent
lamella of silica, which is structureless and solid in Cannosphcera, distinctly fenestrated
in Ccelacantha ; the pores of the latter are irregularly rounded and seem to possess a
thickened margin.

From the surface of the inner shell arise numerous thin, tubular, radial beams
(twenty to eighty or more) and connect it with the outer shell. These beams are
always very thin and straight cylindrical tubules, about twice to four times as long as
the diameter of the inner shell, and usually O'OOl mm. broad, or even less. Their
basal end at their origin from the inner shell is more or less dilated, often funnel-shaped,
so that the surface of the latter appears mammillated (figs. 2, 4). The cavity of the
inner shell seems to pass over immediately into the tubular cavities of the radial beams.
These latter are sometimes simple, at other times articulated or jointed by a number of
transverse septa. The radial beams are covered in all the species observed either with
scattered spines (fig. 5) or with verticils of anchor-threads, very thin, filiform, lateral
branches which bear a spathilla with three or four recurved teeth on the distal end
(figs. 2, 4).

The outer shell is either spherical or an endospherical polyhedron, the prominent
nodal points of which fall into a spherical face. Its diameter is usually from 2 to 3 mm.,
rarely more than 3 or less than 1 mm. Its structure is the same as described for
the Aulosphserida, being composed of hollow cylindrical tubes, which form a loose network
and are separated at its nodal points by astral septa. The meshes of the network are

REPORT ON THE RADIOLARIA. 1639

very large, usually twice to three times as broad as the inner shell, and irregularly
polygonal; the usual and prevailing form is pentagonal, but hexagonal meshes are also
often intermingled, more rarely meshes with four, seven, or eight sides.

The cylindrical tangential tubes possess in general the same shape as in the similar
Aulosphserida, have a thin wall, are filled by jelly, and contain a delicate axial filament
in their axis ; they differ, however, in a peculiar constant character ; in the middle of
each tube is inserted an inner radial beam coming from the inner shell, so that both
together have the form of a T. The central point of insertion has a somewhat shorter
radial distance from the centre of the body than the two nodal points on both ends of
the tangential tube, so that the latter is slightly geniculate (figs. 1—5). The two
halves of each tangential tube are usually somewhat thinner on the central end (where
the inner radial beam is inserted), thicker on the distal end (where the outer radial
tube arises) ; at both ends they are closed by a thin transverse septum. Often also
some other septa are developed, so that each tangential tube seems to be composed
of four to six joints or segments. Usually the tangential tubes are armed with spines
or anchor-threads, similar to those of the inner radial beams. The length of the single
tangential tubes is usually between O'l and 0'3, their diameter from O'Ol to 0'02.

The nodal points of the outer lattice-sphere, in which the outer radial spines arise,
seem to possess the same structure as in the similar Aulosphserida. Since three
tangential tubes are connected in each nodal point, in its centre is the union of three
small astral septa or sutural partitions. The small nodal cavity on the inaide of the
nodal point has probably three small pores, which lead into the three tangential tubes
between the three astral septa. A fourth pore probably leads from the nodal cavity
into the cavity of the hollow radial tube. This structure is difficult to observe, but
seems to be demonstrated by the fact, that in the complete and carefully purified skeletons
which are treated with hot mineral acids and afterwards dried, all cylinders, the
tangential as well as the radial tubes, become easily filled by air (compare the descrip-
tion of the similar structure in the Aulosphserida).

The external radial tubes which arise in the nodal points of the outer shell are either
cylindrical or cylindro-conical, straight, and usually about as long as the diameter of the
inner shell. Their structure and armature is the same as in the similar Aulosphserida.
In the axis of each radial tube runs a delicate axial filament, which is connected with
its thin and fragile wall either by filiform transverse branches or by delicate transverse
septa. The outside of the radial tubes is either smooth (figs. 3-5) or armed with
scattered spines (fig. 4) or with verticils of lateral branches ; each verticil is usually
composed of three or four branches. The distal end of the radial tubes is rarely simple,
pointed ; it is usually armed with a spathilla of three or four curved terminal branches
(figs. 3, 5) sometimes with an elegant corona composed of twenty to thirty thin radially
divergent branches (fig. 4).

1640 THE VOYAGE OF H.M.S. CHALLENGER.

The central capsule of the Cannosphserida is small (of O'l to 0'15 in diameter) and
hidden in the aboral half of the enclosing inner shell, whilst the oral half of the latter is
filled up by the phseodium (figs. 2, 4). The structure of the capsule and of its three
openings seems to be the same as in the closely allied Aulosphserida. I have, however,
not been able to recognise the two parapylse or secondary openings, and have only
observed the astropyle or the main-opening with its radiate operculum surrounded by
the phasodium, and directed with its tubular proboscis towards the mouth of the inner
shell. As R. Hertwig also could not recognise the two parapylse, it is not impossible
that they are wanting, and that the Cannosphserida possess only one opening, the
astropyle, like the Medusettida and Challengerida. The nucleus, enclosed in the central
capsule, is spherical, half or one-third as broad as the latter, and contains numerous
nucleoli.

Synopsis of the Genera of Cannosphcerida.

Internal shell solid, without open pores, ...... 691. Cannosphcera,

Internal shell latticed, with open pores, ...... 692. Caslacantlta.

Genus 691. Cannosphcera,1 Haeckel, 1879, Sitzungsb. med.-nat.
Gesellsch. Jena, Dec. 12, p. G.

Definition. — C annosphserida with a solid, not latticed internal shell.

The genus Cannosphcera comprises those Cannosphserida in which the inner shell is
formed by a thin solid siliceous-plate and exhibits no pores between the prominent bases
of the radial beams.

1. Cannosphcera atlantica, n. sp. (PL 112, figs. 5, 6).

Internal shell not mammillate, with fifteen to twenty radial rods, which are loosely studded
with single, scattered, simple, lateral spines. External shell with irregular, mostly hexagonal
meshes, armed with numerous scattered forks of paired divergent spines, and with twenty to
thirty larger simple radial spines, which are about half as long as the internal rods, and bear at the
distal end a verticil of three to five curved, simple, terminal branches.

Dimensions. — Diameter of the inner shell 01, of the outer 0'5.

Habitat. — Tropical Atlantic, Stations 347 to 349, depth 2250 to 2450 fathoms.

2. Cannosphcera antarctica, n. sp. (PI. 112, figs. 1-3). -.

Internal shell mammillate, with sixty to ninety radial rods, which are studded with cruciate
verticils of tridentate anchor-threads. External shell with irregular, mostly pentagonal meshes,

1 Cannosphcera = Sphere with tubules ; xamx,

REPORT ON THE RADIOLARIA. 1641

the bars of which bear on the outside bunches of similar tridentate anchor-threads. At each
nodal point arises a simple, smooth, radial spine, which bears at the distal end a verticil of three
or four small, curved, terminal branches.

Dimensions. — Diameter of the inner shell 0'2 to 0'3, of the outer T5 to 2'0.

Habitat. — Antarctic Ocean, Stations 154 to 157, depth 1300 to 1975 fathoms.

3. Cannosphcera pacifica, n. sp. (PL 112, fig. 4).

Internal shell mammillate, with one hundred to one hundred and twenty radial rods, which are
studded with cruciate verticils of tridentate anchor-threads. External shell with irregular, mostly
hexagonal meshes, the bars of which bear on the outside and on the inside bunches of similar
tridentate anchor-threads. At each nodal point arises a simple, thorny, radial spine, which bears
at the distal end an elegant verticil of fifteen to twenty flatly expanded, thin, terminal
branches.

Dimensions. — Diameter of the inner shell 0'25 to 0'35, of the outer 2-0 to 2-5.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

Genus 692. Ccelacantha,\ R. Hertwig, 1879, Organism, d. Radiol., p. 91.
Definition. — C annosphaerida with a latticed internal shell.

The genus Ccelacantha comprises those Cannosphserida in which the inner shell is
formed by a fenestrated flint-plate, and exhibits numerous pores between the prominent
bases of the radial beams.

1. Ccelacantha anchorata, R. Hertwig.

Ccelacantha anchorata, R. Hertwig, 1879, Organism, d. Radiol., p. 92, Taf. ix. fig. 2.

Internal shell slightly mammillate, with thirty to forty radial rods, which are densely studded
with verticils of tridentate anchor-threads. External shell with irregular, mostly pentagonal
meshes, the bars of which bear the same verticils, each composed of three thin, tridentate anchor-
threads. At each nodal point arises a slender radial spine, which bears six verticils, each
composed of three to five lateral branches.

Dimensions. — Diameter of the inner shell 0'5, of the outer 3'0.

Habitat. — Mediterranean, Messina (E. Hertwig), surface,

2. Ccelacantha, mammillata, n. sp.

Internal shell strongly mammillate, with sixty to eighty radial rods, which are densely studded
with cruciate verticils of quadridentate anchor-threads. External shell with irregular, mostly

1 Ccdacantha = Hollow spine ; xoiXoV, a.r.ou/6<*.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 206

1642 THE VOYAGE OF H.M.S. CHALLENGER.

hexagonal meshes, the bars of which bear the same verticils, each composed of four thin quadri-
dentate anchor-threads. At each nodal point arises a slender, smooth, radial spine, which bears at
its distal end a verticil of four large, curved, terminal branches.

Dimensions. — Diameter of the inner shell 0'4, of the outer 3'2.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Order III. PILEOGROMIA, Haeckel, 1879.

Definition. — PH^EODARIA with a simple, not bivalved lattice-shell, which assumes
very different forms, but is always provided with a peculiar mouth and peristome on the
oral pole of the main axis. Central capsule always excentric, placed in the aboral half
of the shell-cavity.

Family LXXVIII. CHA LLENGERIDA, John Murray (PL 99).

Challengerida, John Murray, 1876, Proc. Eoy. Soc. Lend., vol. xxiv. p. 471, pi. xxiv. figs. 1, 2.

Definition. — PH^EODARIA with a monaxonial, usually ovate or lenticular shell,
which exhibits a peculiar, fine, regularly hexagonal, diatomaceous structure, and is
usually provided with teeth on the mouth, but without articulated feet. Central capsule
excentric, placed in the aboral .half of the shell-cavity.

The family Challengerida represent a large, peculiar, and interesting group of
PH^EODARIA, which are, for the most part, inhabitants of great depths, and were
perfectly unknown before the discoveries of the Challenger. The first note on these
remarkable Eadiolaria was given in 1876 by John Murray, in his Preliminary Reports
on Work done on board the Challenger (Proc. Roy. Soc. Lond., vol. xxiv. pp. 471,
536, pi. xxiv. figs. 1, 2). He described the peculiar exceedingly beautiful tracery of
their shell, similar to that of the Diatomacese, the enclosed central capsule coloured by
carmine, and the surrounding mass of black-brown pigment lumps (the phseodium).
" At times these Challengerida come up with a good deal of sarcode outside of the
shell, and two specimens have been seen to throw out elongated pseudopodia" (loc. cit.,
p. 536). He found also the shells in the Radiolarian ooze of the deep sea. The
number of different forms found in the collection of the Challenger is so great, that I
can describe in the following pages not less than six genera and fifty-eight species. A
part of these have already been figured by Dr. John Murray in the Narrative of the
Challenger Expedition, vol. i. p. 226, PL A, 1885.

In my first preliminary note on the PH^EODARIA, in 1879, I gave a stricter definition

REPORT ON THE RADIOLARIA. 1643

of the Challengerida (Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12, 1879, p. 5). But
I united at that time the true Challengerida with the Tuscarorida, which, however, are
sharply separated by the entirely different structure of their shell. In Plate A given by
Dr. John Murray, and mentioned above, figs. 1-14 represent genuine Challengerida,
with diatomaceous shell -structure, whilst figs. 15—20 are Tuscarorida, with porcellanous
shell-structure. These latter, therefore, are more closely allied to the Circoporida,
whilst the Challengerida exhibit a closer affinity to the Medusettida and Castanellida.
But the two latter families never possess that peculiar extremely regular and delicate
diatomaceous structure which is exhibited only by the Challengerida.

The general form of the Challengerida is rather simple, usually more or less ovate,
sometimes nearly triangular, at other times subspherical. In nearly all species, with a few
exceptions, the shell is more or less compressed from the two sides, so that its horizontal
transverse section is not circular, but elliptical or lanceolate. In many species the
shell is more or less lenticular, with a sharp or sometimes keeled margin. This margin
lies in the sagittal plane of the body, whilst the two flat sides are right and left. The
main axis is always perpendicular, and its oral or anterior pole is marked by the open
mouth of the shell ; the latter is in the living organism probably the upper pole,
whilst the opposite aboral or posterior pole (often marked by large spines) is the lower
pole. The dorsal margin of the mouth is usually different from the ventral, and in the
majority of species this difference is so striking, that right and left sides of the body
may be recognised immediately, the fundamental form being dipleuric or bilaterally-
symmetrical. In a few species, however, and mainly in those simplest forms in
which the ovate shell has a circular mouth without teeth, and a circular transverse
section, that difference is not recognisable, and the ovate shell is monaxonial, as it is in
Gromia and Lagena among the Foraminifera (PL 99, figs. 19, 20, 22). The size of the
shell is in the majority of species between 0'2 and 0'5 mm.; there are, however, some
very small species, in which the diameter of the shell is only 0'05 to 0'08, or even less ;
and some large species, the diameter of which attains 0'8 to 0'9 mm.

The peculiar structure of the siliceous shell -wall, which we call shortly "diato-
maceous," and by which the Challengerida differ from all the other PH^EODARIA, has
been already represented very well by Dr. John Murray, in PL A. of the Narrative
(vol. i. p. 266, figs. Ic—le, 2a, 4a, 7a, 76). This elegant diatomaceous structure is
extremely similar or nearly identical with that well-known regular structure which we
find in the common Diatomacese or Bacillarise. The entire surface of the shell is
covered with a very great number of very small pit-like depressions, perfectly regular,
circular in form, equal in size, and quincuncial in arrangement. The neighbouring
equidistant pits are always surrounded by regular hexagonal frames of equal size, and
the prominent fine crests of these frames produce the regular hexagonal tracery, which
gives to the shell such a striking similarity to that of the Diatomacese. According to

1644 THE VOYAGE OF H.M.S. CHALLENGER.

the different positions to which the focus of the microscope is brought, the hexagonal
tracery exhibits a different appearance ; either a regular network of equal hexagonal
frames, or a lattice with equal and equidistant circular openings, or a combination of
three crossed and equidistant systems of parallel lines (crossed at angles of 120°).
All the well-known and often discussed optical phenomena which are observed in the
valves of the Diatomacese, reappear also on the shell of the Challengerida.

To recognise the true nature of this diatomaceous structure, sections and slides of
the shell are required, and also fragments of broken shells, the broken margins of which
are of special value for obtaining further explanation. The figures given by Dr. J. Murray
(loc. cit., PI. A) have already demonstrated that the pit-like depressions are regular small
cavities in the flinty shell -wall, which possess an inner and an outer opening. These
intraparietal cavities are either spherical (fig. 76) or cylindrical (fig. Id, 4a) or spindle-
shaped, with a constriction (fig. 2a). Further accurate examinations probably will show
a greater variety in their shape. But each cavity constantly possesses two small openings,
one on the outer, and the other on the inner surface of the shell-wall. Closer examina-
tion (especially of broken shells and slides) proves the presence of these two openings,
which in the smaller species seem to be absent on the first view. I may, therefore,
suppose that also in the similar valves of the Diatomacese, which exhibit exactly the
same structure, an inner and an outer opening are always present in each hexagonal pit,
and that the very small size alone prevents them from being recognised. The regular
hexagonally-framed cavities in the shell-wall of the Challengerida (probably also of the
Diatomacese) are therefore genuine pores, differing from the pores of other Badiolaria
only in their smaller size and the dilatation of the middle part, which is much wider than
the two openings.

The mouth of the shell, its single larger opening, exhibits in the various
Challengerida a great variety in form and structure, and offers the best means for
separating genera and species. According to its essential shape two different sub-
families and six genera may be distinguished in this family. In the first subfamily,
Lithogromida, the mouth is a simple large opening in the wall of the shell on the oral
pole of its main axis (PI. 99, figs. 1—15). In the second subfamily, Pharyngellida, the
mouth is prolonged into a cylindrical hollow tube, which is prominent into the shell-
cavity, and comparable to the pharynx of the Metazoa in general form and function
(PI. 99, figs. 16—20). In this case we may distinguish an inner and an outer mouth
of the tubular pharynx.

In a few forms of both subfamilies the mouth is toothless, smooth, and not armed
with prominent external spines or teeth, as in Lithogromia, the simplest form of all
(PL 99, fig. 22) and in Entocannula (figs. 19, 20). In the great majority of
Challengerida, however, the outer opening of the mouth, is armed with one or more
teeth, usually strong prominent spines (figs. 1—18). Usually the base of these teeth is

REPORT ON THE RADIOLARIA. 1645

semitubular or a half cylinder, forming a more or less prominent peristome or a
proboscis ; and always in this case the open concave side of the canal-shaped groove
is directed towards the ventral side of the shell, the closed convex side towards the
dorsal side. When several teeth arise from the two lateral free margins of the groove,
they are also directed towards the ventral side (figs. 2, 12, 17, &c.). Often a deep
ventral incision or a guttural constriction separates the base of the proboscis from the
genuine shell. The structure of this proboscis or peristome is usually the same as in
the diatomaceous shell-wall ; but sometimes its lattice-work assumes a different shape.

The opening of the mouth itself is rarely circular, usually it is elliptical or even
lanceolate, often triangular. Sometimes two prominent opposite lips may be distin-
guished as right and left, when the fissure of the mouth is prolonged in a sagittal
or longitudinal direction ; as upper and lower, when it is prolonged in a frontal or
transverse direction. The upper or dorsal lip is always more developed than the lower
or ventral ; and the entire semitubular proboscis may be regarded as a production of
the upper lip. Sometimes the latter attains an extraordinary size and development, the
greatest in Challengeria murrayi (PL 99, fig. 1).

The teeth of the mouth, which arise from the upper lip, are usually hollow, at least
on the base ; a prolongation of the shell-cavity arising into the base of the teeth. Their
form is very variable, conical, lanceolate, triangular, sabre -shaped, &c. Usually they
are more or less curved, and shorter than the radius of the shell; rarely they are straight,
and longer than the radius (PI. 99, figs. 5, 6). More important is their different
number, which we have employed for the distinction of subgenera ; future observations
may prove that they are different genera. The most important are the following cases :
—(A.) a single odd dorsal tooth (figs. 5, 16) ; (B.) two paired lateral teeth (figs. 4, 6, 17);
(C.) three teeth, an odd dorsal and two paired lateral (figs. 7, 9, 10) ; (D.) four paired
teeth, two dorsal and two ventral (figs. 3, 13); (E.) five teeth, an odd dorsal and two
pairs of lateral (figs. 2, 12) ; (F.) six teeth in three lateral pairs (fig. 1).

The teeth of the peristome are not the only apophyses which arise from the shell of
the Challengerida. In the majority other spines appear on the sagittal margin, which
separates the right and left halves of the shell. These marginal spines are characteristic
of the genera Challengeron and Porcupinia ; they are usually radially directed, straight,
conical, sometimes solid, at other times hollow. Their number and arrangement is very
variable and serves for the distinction of species ; the following differences are the most
important : — (A.) a single odd spine on the apical pole of the shell, in the principal axis,
opposite to the centre of the mouth (PI. 99, figs. 6, 7); (B.) two aboral spines, a dorsal
and a ventral (figs. 8-10) ; (C.) a bunch or a crowded group of radial spines on the
aboral margin of the shell, usually one larger apical spine surrounded by several smaller
dorsal and ventral (figs. 11, 12, 16) ; (D.) numerous radial spines along the whole sagittal
margin of the shell (figs. 13-15).

1646 THE VOYAGE OF H.M.S. CHALLENGER.

The central capsule of the Challengerida is constantly placed in the aboral half of
the shell -cavity, whilst its oral half is occupied by the phseodium ; the intervals between
them and the inner surface of the shell are filled up by the calymma. Frequently
from the outer surface of the capsule arise numerous branched streams of sarcode, which
pierce the calymma and are directed towards the inside of the shell-wall, where they
are united by a thin continuous layer of protoplasm (PL 99, fig. 1). The phseodium is
usually more voluminous than the capsule and envelops the latter on its anterior or
oral face ; more rarely the entire capsule is hidden in the phseodium. The phasodella,
constituting the latter, are of very different sizes, of variable colour, olive and greenish -
brown, red-brown, black-brown or nearly black. In some preparations, stained with
carmine, numerous red coloured granula, similar to nuclei, were scattered in the
phseodium (compare Murray, loc. cit., PI. A, figs. 1—14).

The diameter of the central capsule is usually about one-half or one-third as great as
that of the enclosing shell (PL 99, figs. 1—20). Its form is either spherical or slightly
compressed, spheroidal, or sometimes lenticular. The large nucleus has the same form,
is about half as broad as the capsule and contains numerous nucleoli. Sometimes the
capsule contained two nuclei of equal size, and in a few specimens the shell contained
two central capsules, each with a nucleus, so that the Challengerida seem to propagate
also by self-division (PI. 99, fig. 6).

The astropyle, or the large opening of the central capsule, exhibits the usual radiate
operculum of the PHJSODARIA, and the tubular proboscis arising from it. This is
constantly placed on the oral or anterior pole of the capsule and directed towards the
mouth of the shell. I was never able to discover any parapyle or secondary opening
in the central capsule, though numerous and well-preserved specimens of the Challenger
collection were accurately examined. It seems therefore that the Challengerida are not
TRIPYLEA (as the majority of PH^EODARIA), but MONOPYLEA with a single opening (like
the closely allied Medusettida and Castanellida).

Synopsis of the Genera of Challengerida.

I. Subfamily f Shell smooth, without adoral teeth and marginal spines, . 693. Lithogromia.

Lithogromida.

Shell without pharynx or \ Shell with adoral teeth, but without marginal spines, . 694. Challengeria.

inner prominent tube of |
the mouth. [ Shell with adoral teeth and with marginal spines, . . 695. Challengeron.

II. Subfamily

Pharyngellida.
Shell with a pharynx, or
an inner cylindrical tube,

Shell smooth, without adoral teeth and marginal spines, . 696. Entocannula.
Shell with adoral teeth, but without marginal spines, . 697. Pharynyella.

ind 3*r ; t ' 'd Shell with adoral teeth and with marginal spines, . . 698. Porcupinia.

REPORT ON THE RADIOLARIA. 1647

Subfamily 1. LITHOGKOMIDA, Haeckel.

Definition. — C hallengerida without pharynx, with a simple mouth, not pro-
longed into an inner prominent tube.

Genus 693. Lithogromia,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C hallengerida without pharynx, without adoral teeth and marginal
spines.

The genus Lithogromia and the two following genera represent together the sub-
family Lithogromida, comprising those Challengerida in which the mouth of the shell
is a simple opening, and not prolonged into a pharynx or an internal prominent tube.
Lithogromia may be regarded as the common ancestral form of this family, since it is
the simplest of all, and possesses no external apophyses, neither teeth on the mouth, nor
spines on the margin of the smooth shell.

1. Lithogromia silicea, n. sp. (PI. 99, fig. 22).

Shell ovate, one and a half times as long as broad, not compressed. Transverse section circular.
Mouth a simple circular opening with smooth edges about one-third as broad as the shell.
Dimensions. — Length of the shell 0-2, breadth 015; mouth 0'05.
Habitat. — North Atlantic, Fserbe Channel (Gulf Stream), John Murray, depth 600 fathoms.

2. Lithogromia diatomacea, n. sp. (PI. 99, fig. 21).

Shell ovate, lenticular, one and one-third times as long as broad, strongly compressed. Trans-
verse section elliptical. Mouth a broad fissure, half as broad as the shell.
Dimensions. — Length of the shell 0'27, breadth 0'2 ; mouth O'l.
Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

3. Lithogromia lenticula, n. sp.

Shell subcircular, lenticular, about as long as broad, strongly compressed. Transverse section
lanceolate. Mouth a narrow fissure, one-third as broad as the shell
Dimensions. — Diameter of the shell O'l 5, mouth 0'05.
Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

1 Lithogromia— Siliceous Gromia.

1648 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 694. Challengeria, John Murray, 1876, Proc. Roy. Soc. Lond.,

vol. xxiv. p. 536.

Definition. — Challenger id a without pharynx, with one or more adoral teeth,
but without spines on the sagittal margin.

The genus Challengeria, and the following closely allied Challenger on, differ from
the preceding Lithogromia, their ancestral form, in the development of teeth on the
mouth of the shell. Challengeron has also radial spines on the sagittal margin, while
these are wanting in Challengeria. The latter genus exhibits not less than twenty-one,
the former twenty-five species, so that both together make by far the greatest part of
the family (containing fifty-eight species). They are also more common and more widely
distributed than the four other genera of Challengerida, and many species appear in
great numbers in certain localities. With a few exceptions living on the surface, they
are all inhabitants of great depths.

Subgenus 1. Challengerantha, Haeckel.

Definition. — Peristome with a single simple tooth, which is neither forked nor
branched (Challengerice monodontes).

1. Challengeria naresii, John Murray.

Challengeria naresii, John Murray, 1876, Proe. Roy. Soc. Lond., vol. xxiv. pi. xxiv. fig. 1.
Challengeria naresii, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 236, pi. A,
figs. 1, la-le.

Shell circular or nearly circular, strongly compressed, lenticular. Peristome on the dorsal
corner with a single simple vertical tooth, which is nearly straight, conical, with two sharp lateral
edges on the base, about half as long as the shell.

Dimensions. — Diameter of the shell O5 to 0'6, length of the tooth 0'2 to 0'3.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific, at depths between 1000 and 3000 fathoms.

2. Challengeria xiphodon, n. sp.

Shell circular, nearly spherical, slightly compressed. Peristome on the dorsal corner with a
single simple vertical tooth, which is straight, three-sided prismatic, and as long as the shell.
Dimensions. — Diameter of the shell 01 to 013, length of the tooth 01 to 012.
Habitat. — Tropical Atlantic, Stations 349 to 352, surface.

REPORT ON THE RADIOLARIA. 1649

3. Challengeria sigmodon, n. sp.

Shell circular, nearly spherical, slightly compressed. Peristome with a single simple tooth,
which is S-shaped, more or less curved, and about one-third as long as the shell.
Dimensions. — Diameter of the shell 0'3 to 0'4, length of the tooth 01 to 014.
Habitat. — North Pacific, Station 231, depth 2250 fathoms.

4. Challengeria tritonis, n. sp. (PI. 99, fig. 5).

Shell ovate, slightly compressed. Peristome with a single simple tooth, which is vertical, straight,
slenderly conical, and about half as long as the shell

Dimensions. — Diameter of the shell 015 to 0'2, length of the tooth 01 to 012.

Habitat. — North Atlantic, Fseroe Channel, Gulf Stream, in great numbers, in depths from 100
to 600 fathoms. (Expedition of H.M.S. " Triton," 1882), John Murray.

5. Challengeria pyramidalis, n. sp.

Shell slenderly ovate, one and a half times as long as broad, slightly compressed. Peristome with
a single, simple, large tooth, which is three-sided pyramidal, vertical, straight, and longer than half
the shell.

Dimensions. — Length of the shell 0'6 to 0'8, breadth 0'4 to 0'5 ; length of the tooth 0'4 to 0'5.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

6. Cliallengeria cyrtodon, n. sp.

Shell ovate, lenticular, strongly compressed. Peristome with a single simple tooth, which is
crescent-shaped, curved over the mouth, and about half as long as the shell.

Dimensions. — Length of the shell 04 to 0'5, breadth 0'3 to 0'4 ; length of the tooth 0'2 to 0'25.
Habitat. — South Pacific, Station 289, depth 2550 fathoms.

Subgenus 2. Cliallengeretta, Haeckel.

Definition. — Peristome with a forked or bifid tooth, or with two parallel lateral
teeth (Challengerice diodontes).

7. Challengeria sloggettii, John Murray (PI. 99, fig. 4).

Challeng&ria harstoni, John Murray, 1879 (partim), in litteris, Narr. ChalL Exp., vol. i.
p. 226, pi. A, fig. 14.

Shell triangular, strongly compressed, with three rounded corners, or nearly semicircular ; its
aboral margin straight, horizontal, longer than the convex, dorsal, and ventral margins. Peristome

(ZOOL. CHALL. EXP. PART XL. 1886.) Rl 207

1650 THE VOYAGE OF H.M.S. CHALLENGER.

with two parallel, triangular pointed teeth, which are obliquely ascending, lamellar, with inflated
ovate base, and about as long as the shell-radius.

Dimensions. — Diameter of the shell 0'2 to 0'3, length of the teeth 01 to 015.

Habitat. — Tropical Atlantic, Stations 347, 348, depth 2250 to 2450 fathoms.

8. Challengeria harstoni, John Murray.

CJiallen,geria harstoni, John Murray, 1879, in litteris, Narr. Cliall. Exp., vol. i. p. 226, pi. A,
fig. 14a.

Shell subcircular or somewhat triangular, with convex margins. Peristome with two parallel,
slender, lanceolate teeth, which are obliquely ascending, and about half as long as the shell-radius.
Dimensions. — Diameter of the shell 015 to 018, length of the teeth 0'04 to 0'05.
Habitat. — North Pacific, Station 231, depth 2250 fathoms.

9. Challengeria campbelli, John Murray.

Challengeria campbelli, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A,
fig. 9.

Shell cordate, nearly triangular, compressed, with blunt apex. Peristome in the excavated
middle of the broad base, with two short, parallel, triangular teeth. This species is very similar
to Porcupinia cordiformis (PI. 99, fig. 16), but differs from it in the absence of an internal pharynx
and of external apical spines.

Dimensions. — Diameter of the shell 0'2 to 0'24 ; length of the teeth 0'03 to 0'05.

Habitat. — South Atlantic, Stations 332 to 335, depth 1425 to 2200 fathoms.

10. Challengeria thomsoni, John Murray.

Challengeria thomsoni, John Murray, 1879. in litteris, Narr. Chall. Exp., vol. i p. 226, pi. A,
%. 2.

Shell ovate, slightly compressed, with rounded apical pole. Peristome semitubular, obliquely
ascending, nearly straight, in the lower half an open half-cylinder, in the upper half forked, with
two parallel, thin, oblique teeth. Sometimes a third small (dorsal) tooth is developed.

Dimensions. — Length of the shell 0'3 to 0'35, breadth 0'2 to 0'25 ; length of the peristome 0'08
to 012.

. Habitat. — South Atlantic, Stations 318 to 330, surface, and in depths from 1900 to 2900
fathoms.

11. Challengeria bidens, n. sp.

Shell ovate, strongly compressed, lenticular. Peristome with two curved, long and thin bristle-
shaped teeth, which are obliquely inclined over the mouth, and longer than the radius of the shell.

Dimensions. — Length of the shell 012 to 018, breadth 01 to 014 ; length of the teeth 0'08
to 01.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

REPORT ON THE RADIOLARIA. 1651

12. Challengeria havergalli, John Murray.

Challengeria havergalli, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A,
figs. 13, 13a.

Shell subspherical, slightly compressed. Peristome semitubular, slender, somewhat curved, in
the lower half a simple half-cylinder, in the upper half forked, with two divergent teeth, nearly as
long as the shell.

Dimensions. — Diameter of the shell 01 to 015, length of the peristome 0'08 to 012.

Habitat. — South Pacific, Station 300, depth 1375 fathoms.

13. Challengeria elephas, n. sp.

Shell ellipsoidal, not compressed. Peristome very similar to that of Uhallengeron diodon
(PI. 99, fig. 6), from which this species differs mainly in the absence of an apical spine, and in a
more constricted mouth. The two conical teeth of the mouth are very large, nearly as long as the
shell, straight, and almost parallel, each tooth has a large hole on the thickened base.

Dimensions. — Diameter of the shell 0'22, length of the teeth 0'2.

Habitat. — Indian Ocean, Cocos Islands (Rabbe), surface.

Subgenus 3. Challengerilla, Haeckel.

Definition. — Peristome with three teeth or trifid, with an odd dorsal and two paired
lateral teeth (Challengeria triodontes).

14. Challengeria macleari, John Murray.

Challengeria macleari, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pL A,
fig. 3.

Shell subcircular, lenticular, with a sharp marginal edge. Peristome semitubular, an oblique
half-cylinder, with three divergent, short, triangular teeth ; the dorsal odd tooth nearly vertical, the
paired lateral teeth subhorizontal. Length of the peristome about one-third or one-fourth of the
diameter of the shell.

Dimensions. — Diameter of the shell 0'25 to 0'35, length of the peristome 01 to 012.

Habitat. — South Atlantic, Stations 325 to 332, depth 17.15 to 2900 fathoms.

15. Challengeria tridens, n. sp.

Shell subspherical, slightly compressed. Peristome about as long as the radius of the shell, with
three diverging and obliquely descending teeth ; the dorsal odd tooth twice as long as the paired
lateral teeth.

Dimensions. — Diameter of the shell 0-08 to 012, length of the peristome 0-05 to 0'07.

Habitat. — North Atlantic, Fseroe Channel (Gulf Stream), John Murray.

1652 THE VOYAGE OF H.M.S. CHALLENGER.

16. Challengeria trigona, Haeckel.

Ghallengeria macleari, var., John Murray, 1879, in littens, Narr. Chall. Exp., vol. i. p. 226,
pi. A, fig. 36.

Shell triangular, with three rounded corners ; the two lateral sides nearly straight, equal, the
aboral side more or less convex and somewhat shorter. Peristome a curved half-tube (often longer
than in Murray's figure), one-third to one-half as long as the shell, with three short triangular
diverging and ascending teeth of equal length.

Dimensions. — Length of the shell 0'25 to 0'3, breadth 0'2 to 0'25; length of the peristome O08
to 012.

Habitat. — South Atlantic, Stations 332 to 335, depth 1425 to 2200 fathoms.

17. Challengeria trifida, n. sp.

Shell ovate, more or less compressed, about two-thirds as long as broad. Peristome semi-
tubular, obliquely ascending, about one-third as long as the shell, in the lower half simple, in the
upper trifid, with three curved divergent teeth ; the dorsal odd tooth shorter than the paired lateral
teeth.

Dimensions. — Length of the shell 0'3 to 0'36, breadth 0'24 to 0'28.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

Subgenus 4. Challenger omma, Haeckel.
Definition. — Peristome with four to six or more teeth.

18. Challengeria quadridens, n. sp.

Shell subglobose, with nearly circular perimeter. Peristome an oblique short and broad tube,
the breadth of which is twice as great as its length and equal to the radius of the shell. Margin
of the peristome with four divergent, short, triangular teeth, the two dorsal teeth half as long as the
two ventral.

Dimensions. — Diameter of the shell 0'22 to 0-24, breadth of the peristome O'l.

Habitat. — Central Pacific, Stations 265 to 268, depth 2700 to 2900 fathoms.

19. Challengeria bromleyi, n. sp. (PL 99, fig. 3).

Shell ovate, lenticular, strongly compressed. Peristome a broad, trapezoidal, horizontal lamella,
the breadth of which is twice as great as its length and nearly equal to the diameter of the shell ;
its margin with four divergent triangular lamellar teeth, the two dorsal teeth three times as long
as the two ventral.

Dimensions. — Length of the shell 0'08 to 01, breadth 0'05 to- 0'07 ; breadth of the peristome
0-08.

Habitat. — North Pacific, Stations 244 to 253, surface, and in various depths.

REPORT ON THE RADIOLARIA. 1053

20. Challengeria ivildi, n, sp. (PL 99, fig. 2).

Shell subspherical, slightly compressed. Peristome semitubular, curved, as long as the shell-
radius ; with five curved lamellar teeth, an odd longer dorsal tooth and two pairs of lateral teeth.
Dimensions. — Diameter of the shell 012 to 018, length of the peristome 0'08 to 012.
Habitat. — Tropical Atlantic, Stations 347 to 348, depth 2250 to 2450 fathoms.

21. Challengeria aldrichi, John Murray.

Challengeria aldrichi, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A, fig. 4.

Shell subspherical, slightly compressed. Peristome a collar-like curved lamella, the breadth of
which is twice as great as its length, and equals the radius of the shell ; its margin with six short
triangular teeth, two convergent ventral, two external horizontal lateral, and two ascending dorsal.

Dimensions. — Diameter of the shell 0'2, breadth of the peristome 01.

Habitat. — North Pacific, Station 244 to 248, depth 2050 to 2900 fathoms.

22. Challengeria murrayi, n. sp. (PI. 99, fig. 1).

Shell subcircular, lenticular, strongly compressed. Peristome a trapezoidal, curved, collar-like
lamella, the breadth of which is three times as great as its length and equal to the diameter of the
shell ; its margin with six triangular teeth, disposed like the preceding species, but larger.

Dimensions. — Diameter of the shell 015, breadth of the peristome 015.

Habitat. — North- Western Pacific (south of Japan), Station 231, depth 2250 fathoms.

Genus 695. Challengeron, John Murray, 1879, in litteris et schedulis.

Definition. — C hallengerida without pharynx, with one or more teeth on the
mouth, and with marginal spines.

The genus Challengeron has in general the same shape as the preceding closely
allied Challengeria, but differs from it in the development of radial spines on the
sagittal margin of the shell, which in the latter genus is smooth. According to the
different number and arrangement of these marginal spines, which give a very singular
appearance to them, we divide the twenty -five species of this cosmopolitan genus into
four subgenera : — (l) with a single, odd apical spine ; (2) with two opposed aboral spines
(a dorsal and a ventral) ; (3) with a bunch of aboral spines ; (4) with numerous radial
spines along the whole sagittal margin of the shell.

Subgenus 1. Challenger anium, Haeckel.

Definition. — Margin of the shell with a single spine on the apical pole, opposite to
the peristome (Challengerice caudatce).

1654 THE VOYAGE OF H.M.S. CHALLENGER.

1. Challengeron monodon, n. sp.

Shell subspherical, slightly compressed, with a single straight conical spine on the apical pole,
about as long as the radius. Peristome with a single vertical, straight, conical tooth, diametrically
opposite to the apical spine and of the same length. (Similar to CJiallengeria naresii.)

Dimensions. — Diameter of the shell 0'2 to 0'3, length of the two opposite spiueb 01 to 015.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

2. Challengeron cochlear, n. sp.

Shell nearly circular, lenticular, strongly compressed, with a single straight conical spine on the
apical pole, about half as long as the radius. Peristome spoon-shaped, obliquely curved and inclined
over the mouth, with a single terminal tooth, somewhat longer than the radius.

Dimensions. — Diameter of the shell 01, length of the peristome 0'06.

Habitat. — Indian Ocean, Cocos Islands, Rabbe, surface.

3. Challengeron diodon, n. sp. (PL 99, fig. 6).

Shell ovate, slightly compressed, with a single straight conical spine on the aboral pole, half as
long as the radius. Peristome short and broad, collar-shaped, about twice as broad as long, and
half as long as the radius, obliquely inclined over the mouth, with two divergent straight teeth,
which are conical and longer than the shell-radius ; beyond each tooth a large ovate hole in the
wall of the peristome.

Dimensions. — Diameter of the shell 0'08 to 01, length of the teeth 0'06 to 0'08.

Habitat. — South-Eastern Pacific, Station 298, depth 2225 fathoms.

4. Challengeron pearceyi, n. sp. (PL 99, fig. 7).

Shell ellipsoidal or subspherical, scarcely compressed, with a single straight conical spine on
the apical pole, about as long as the diameter. Peristome slender, semitubular, nearly as long as
the diameter, somewhat obliquely inclined over the mouth, with three divergent triangular or
lanceolate teeth ; the dorsal odd tooth about twice as large as the paired lateral teeth.

Dimensions. — Diameter of the shell 0-08 to 012, length of the peristome 0'08 to 01.

Habitat. — Antarctic Ocean, between Kerguelen and Heard Island, Station 157.

5. Challengeron swirei, John Murray.

Challengeria swirei, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A, fig. 11.

Shell subspherical or somewhat ovate, with a single straight conical spine on the apical pole,
about as long as the radius. Peristome slender, semitubular, straight and vertical, nearly as long as
the shell, with three pointed teeth, an odd longer terminal and two paired shorter lateral.

Dimensions. — Diameter of the shell 0'06 to 0'08, length of the peristome 0'05 to 0'06.

Habitat. — Antarctic Ocean, Station 157, surface, common.

REPOKT ON THE RADIOLABIA. 1655

6. Challengeron triodon, n. sp.

Shell ovate, one and a half times as long as broad, not compressed, with a single short and stout
conical spine on the apical pole, shorter than half the radius. Peristome short and broad, collar-
shaped, nearly half as broad and one-third as long as the shell, with three divergent terminal teeth,
an odd dorsal and two paired lateral.

Dimensions. — Length of the shell 0'25 to 0 '3, breadth 015 to 0'2 ; length and breadth of the
peristome 01.

Habitat. — North Pacific, Station 245, surface.

Subgenus 2. Challenger ebium, Haeckel.

Definition. — Margin of the shell with two widely distant aboral spines, opposite
in the sagittal plane, a dorsal and a ventral.

7. Challengeron balfouri, John Murray.

Challengeria balfouri, John Murray, 1879, in litteris, Narr. Chall. Exp.,vol. i. p. 226, pi. A, fig. 10.

Shell subcircular, lenticular, strongly compressed, with two short divergent spines on the apical
margin (a dorsal and a ventral). Peristome slender, semitubular, as long as the radius, vertical, in
the distal half forked, with two parallel teeth.

Dimensions. — Diameter of the shell 0'08 to 016, length of the peristome 0'04 to 0'08.

Habitat. — North Atlantic, Stations 353 to 354, Hebrides, surface.

8. Challengeron golfense, n. sp.

Shell ovate, lenticular, compressed, with two short divergent spines on the apical margin (a
dorsal and a ventral). Peristome slender, semitubular, half as long as the radius, with three
terminal teeth, two short, vertically ascending, paired teeth and a larger odd tooth, which is
inclined obliquely over the mouth.

Dimensions. — Diameter of the shell 015 to 0'2, peristome 0'05 to 0'07.

Habitat. — North Atlantic, Faroe Channel, Gulf Stream, surface and at various depths, John
Murray.

9. Challengeron richardsii, n. sp. (PI. 99, fig. 8).

Shell subcircular, lenticular, strongly compressed, with two stout, divergent, straight spines on
the aboral margin (a dorsal and a ventral) which reach the length of the radius. Peristome
slender, semitubular, slightly curved, about as long as the radius, with three short, divergent,

1656 THE VOYAGE OF H.M.S. CHALLENGER.

terminal teeth. Mouth obliquely truncate. The dorsal odd tooth is nearly vertical, the two
lateral paired teeth almost horizontal.

Dimensions. — Diameter of the shell 0'2 to 0'25, length of the spines and the peristome 0'08
to 0-12.

Habitat. — Antarctic Ocean, Station 157, surface, common.

10. Challengeron fergusoni, n. sp. (PL 99, fig. 9).

Shell isosceles triangular, with three slightly convex edges and two short, nearly vertically
descending spines on the two corners of the aboral margin. Peristome inversely funnel-shaped,
with a deep ventral incision on the base, and three broad, ovate, triangular teeth. The dorsal odd
tooth is nearly vertical, whilst the two lateral paired teeth are almost horizontal ; therefore the
angle between the former and the latter is about a right angle.

Dimensions. — Diameter of the shell 0'2 to 0'3, length of the peristome 01.

Habitat. — Western Tropical Pacific, Station 224, depth 1850 fathoms.

11. Challengeron tizardi, John Murray.

Challengeria tizardi, John Murray, 1879, in litteria, Narr. Chall. Exp., vol. i. p. 226, pi. A,
figs. 7-76.

Shell nearly equilateral triangular, with concave ventral, convex dorsal and aboral edges, on
the two corners of the latter two opposite horizontal spines (a dorsal and a ventral). Peristome
auriculate and bilobate, with a deep ventral incision on the base, and three pointed triangular
teeth, the upper margins of which are nearly horizontal.

Dimensions. — 'Diameter of the shell 0~22 to 0'3, length and breadth of the peristome O'Ol to 012.

Habitat. — South Atlantic, Stations 332 to 335, depth 1425 to 2200 fathoms.

12. Challengeron triangulum, n. sp. (PL 99, fig. 10).

Shell nearly equilateral triangular, with three slightly convex or nearly straight sides, and two
opposite obliquely descending and diverging spines on the two corners of the aboral margin.
Peristome auriculate and bilobate, with a very thin basal neck and a deep incision on its ventra
side ; its distal margin is obliquely truncate, and exhibits an odd ascending dorsal tooth and two
parallel, paired, descending, lateral teeth.

Dimensions. — Diameter of the shell 0'2 to 0'3 ; length and breadth of the peristome 01 to 012.

Habitat. — North Pacific, Stations 244 to 253, depth 2050 to 3125 fathoms.

Subgenus 3. Challengeridium, Haeckel.

Definition. — Margin of the shell smooth on the dorsal and the ventral side, but
with three to five or more large spines (or a bunch of spines) on the aboral side ; the
middle spine is placed in the main axis, and larger than the others.

REPORT ON THE RADIOLARIA. 1657

13. Challengeron bisternum, n. sp.

Shell subcircular, lenticular, strongly compressed, with three stout conical spines on the aboral
pole ; the middle spine is placed in the main axis, as long as the radius and three times as long
as the two others. Peristome semitubular, straight, vertical, about as long as the radius, with three
divergent teeth, the middle of which is odd and twice as large as the two paired lateral teeth.

Dimensions. — Diameter of the shell 0'22 ; length of the peristome 01.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

14. Challengeron heptacanthum, n. sp.

Shell ovate, slightly compressed, with a series of five stout, conical, radial spines on the aboral
margin ; the middle spine is placed in the mam axis and longer than the radius, twice as long as
the two next, and three times as long as the more distant spines. Peristome short and broad,
collar-shaped, with two large, divergent, straight teeth, each of which is longer than the shell-radius
and bears, at its base a large hole.

Dimensions. — Length of the shell 0'09 to Oil, breadth 0'07 to 0'08 ; length of the teeth 0'07.

Habitat. — Tropical Atlantic, Stations 347, 348, depth 2250 and 2450 fathoms.

15. Challengeron crosbiei, n. sp. (PI. Q9} fig. 11).

Shell ovate, strongly compressed, with a series of seven to nine conical spines on the aboral
margin ; the middle spine is placed in the main axis, as long as the radius, and much larger than
the six or eight other spines. Peristome short and broad, collar-like, with several small spines
and two slender, widely distant, conical teeth, which are half as long as the shell, and curved
towards one another like a pincer, each with a large hole at its base.

Dimensions. — Length of the shell 0'08 to 0'09, breadth 0'06 to 0'07 ; length of the two larger
teeth 0-04 to 0'05.

Habitat. — Central Pacific, Station 270 to 274, depth 2350 to 2925 fathoms.

16. Challengeron buchanani, n. sp. (PI. 99, fig. 12).

Shell ovate, slightly compressed, with a terminal comb of nine to twelve conical radial spines,
densely crowded on the aboral pole ; the middle spine is placed in the main axis, about half as long
as the shell and much larger than the others. Peristome subconical, semitubular, recurved, half as
long as the shell, with five triangular teeth ; the dorsal odd tooth is inclined backwards, the two
parallel pairs of lateral teeth directed ventrally.

Dimensions. — Length of the shell 015 to 018, breadth 01 to 012 ; length of the peristome
0-06 to 0-08.

Habitat.— Tropical Atlantic, Station 348, depth 2450 fathoms.

(ZOOL. CHALL. EXP. — PART XL. 1886.) Rr 208

1658 THE VOYAGE OF H.M.S. CHALLENGER.

Subgenus 4. Challengerosium, Haeckel.

Definition. — Margin of the shell dentated or serrated, with a continuous series of
numerous short radial spines.

17. Challengeron channeri, John Murray.

Cliallengeron channeri, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pL A,
fig. 12.

Shell subcircular, lenticular, strongly compressed, with fourteen to eighteen slender, straight,
radial spines on the margin ; the spines are straight, equidistant, cylindrical, and about as long as
the radius of the shell Peristome short, with two parallel, vertical, lateral, straight teeth, which are
less than half the length of a spine.

Dimensions. — Diameter of the shell 0'14 to O'l7 ; length of the spines O06 to 0'08.

Habitat. — North Pacific, Station 231, depth 2250 fathoms.

18. Challengeron moseleyi, n. sp. (PI. 99, fig. 14).

Shell circular, lenticular, strongly compressed, with thirty to forty slender, straight, equidistant,
radial spines on the margin, larger and smaller spines alternating; the larger spines are about as
long as the radius, the smaller only half as long. Peristome short, tubular, with two divergent
ovate or nearly triangular teeth, a dorsal and a ventral, about as long as the shorter marginal spines.

Dimensions. — Diameter of the shell 0'13 to 015 ; length of the larger spines 0'6 to 0'07, of the
smaller 0'03 to 0'04.

Habitat. — North Pacific, Station 244, depth 2900 fathoms.

19. Challengeron bethelli, John Murray.

Challengeron bethelli, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A,
fig. 6.

Shell subcircular, lenticular, strongly compressed, with numerous (twenty to thirty) short
conical spines on the margin (often wanting in the upper part of the dorsal margin). Peristome
with a deep labial incision and two parallel triangular lateral teeth, the upper margin of which
is horizontal.

Dimensions. — Diameter of the shell 0'2 to 0'25; length of the spines 0'02 to 0'03.

Habitat. — North Pacific, Stations 238, 241 (off Japan), depth between 2300 and 3950 fathoms.

20. Challengeron bathybium, n. sp.

Shell subcircular, lenticular, slightly compressed, with a corona of numerous (thirty to forty or
more) short, conical, radial spines on the margin. Peristome helmet-shaped, nearly as long as the

REPORT ON THE RADIOLARIA. 1659

radius, with two widely divergent, conical, curved teeth, a vertical dorsal and a nearly horizontal
ventral tooth.

Dimensions. — Diameter of the shell 0'22 ; length of the peristome 01.

Habitat. — Western Tropical Pacific, Station 225, depth 4475 fathoms.

21. Challengeron johannis, n. sp.

Shell ovate, slightly compressed, with a corona of numerous (forty to sixty or more) short radial
spines on the margin, ten to fifteen of them (in the aboral half) are pyramidal, and much larger than
the others. Peristome helmet-shaped, about one-third as long as the shell, with a deep bosom and
two widely divergent teeth on the concave upper margin, a forked dorsal and a conical ventral.

Dimensions. — Length of the shell 013, breadth 01 ; length of the peristome 0'04.

Habitat. — North Atlantic, Fseroe Channel (Gulf Stream), John Murray.

22. Challengeron carpenterii, John Murray.

CJiallengeron carpenterii, John Murray, 1877, in litteris, Narr. Chall. Exp., vol. i. p. 226, pL A,

fig. 8.

Shell ovate, with a series of twelve to fifteen short, conical, radial spines on the aboral half of
the margin. Peristome slender, semitubular, nearly as long as the shell, in the upper half forked,
with two short parallel teeth.

Dimensions. — Length of the shell 013 to 018, breadth 01 to 014; length of the peristome
01 to 012.

Habitat. — Tropical Atlantic, Stations 347 to 348, depth 2250 to 2450 fathoms.

23. Challengeron ciliatum, n. sp.

Shell ovate, slightly compressed, with numerous (forty to fifty or more) short and thin, bristle-
shaped, radial spines on the margin. Peristome obliquely truncate, with three curved spines ; the
dorsal odd spine subvertical, nearly as long as the radius, and much stronger than the two parallel,
nearly horizontal, lateral spines.

Dimensions. — Length of the shell 015, breadth Oil ; length of the peristome 01.

Habitat. — North Pacific, Station 231, depth 2250 fathoms.

24. Challengeron willemoesii, n. sp. (PI. 99, fig. 13).

Shell broadly-ovate or nearly circular, lenticular, with numerous (fifty to sixty) short and stout,
conical, radial spines on the margin, increasing in size towards the aboral pole ; the spines are
alternately larger and smaller, the largest about half as long as the radius. Peristome helmet-
shaped or half conical, longer than the radius of the shell, with two pairs of conical, curved,

1660 THE VOYAGE OF H.M.S. CHALLENGER.

divergent teeth ; the terminal teeth are the halves of a forked dorsal tooth and diverge laterally ;
the lower teeth are nearly horizontal and directed ventrally.

Dimensions. — Diameter of the shell 013 to 015 ; length of the peristome 0-07 to 01.

Habitat. — Tropical Pacific, Stations 274 to 276, depth 2350 to 2750 fathoms.

25. Challengeron wyvillei, n. sp. (PL 99, fig. 15).

Shell ovate, lenticular, strongly compressed, with numerous (forty to fifty) short, conical, radial
spines on the margin ; the spines are larger on the ahoral side and spinulate. Peristome narrow,
with two parallel, lateral, lamellar, forked teeth, about as long as the radius ; the upper branch
of the forks is sabre-shaped, obliquely truncate, subvertical, ciliate, and much broader than the
lower nearly horizontal branch, which is directed towards the ventral side and curved upwards.

Dimensions. — Length of the shell 012 to 016, breadth 01 to 014 ; length of the peristome
0-08 to Oil.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

Subfamily 2. PHARYNGELLIDA, Haeckel.

Definition. — Ch allengerida with a pharynx, or an internal prominent mouth
tube.

Genus 696. Entocannula,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C hallengerida with a pharynx, without teeth on the mouth, and
without marginal spines.

The genus Entocannula and the two following genera represent together the sub-
family Pharyngellida, differing from the preceding Lithogromida in the development of
a peculiar pharynx, an internal, cylindrical, or funnel-shaped tube, which is conspicuous,
leads from the mouth into the shell-cavity, and is provided with an inner and an outer
opening. The Pharyngellida are much rarer than the Lithogromida ; only ten species have
been observed of the former, fifty of the latter. Entocannula is the simplest form of
the Pharyngellida, having a smooth shell, without aboral teeth and marginal spines ; it
differs from Lithogromia only in the possession of the pharynx. One remarkable
species is covered entirely with extremely thin, flinty hairs, and may represent therefore
a peculiar genus, Trichogromia.

1 Entoeannula Shell with an internal tube.

REPORT ON THE RADIOLARIA. 1661

1. Entocannula circularis, n. sp.

Shell circular or nearly circular, lenticular, strongly compressed. Pharynx cylindrical, one-
third or one-fourth as broad as the shell, twice as broad as long, its outer and inner apertures of
equal breadth. Surface smooth.

Dimensions. — Diameter of the shell 0'20 to 0'32, of the pharynx 0'07 to 0'09.

Habitat. — North Pacific, Station 250, depth 3050 fathoms.

2. Entocannula subglobosa, n. sp.

Challengeria bromleyi, (partim), John Murray, 1879, in scliedulis Chall. Coll.

Shell circular, nearly spherical, slightly compressed. Pharynx funnel-shaped, truncate, conical,
its outer opening twice as broad as the inner. Surface smooth.
• Dimensions. — Diameter of the shell 0'25 to 0'28, of the inner mouth 0'05.
Habitat. — South Pacific, Station 289, depth 2550 fathoms.

3. Entocannula infundibulum, n. sp. (PI. 99, fig. 19).

Challengeria bromleyi (partim), John Murray, 1879, in litteris, Narr. Chall Exp., vol. i. p. 226,
pi. A, fig. 5.

Shell ovate, truncate at the mouth, slightly compressed. Pharynx funnel-shaped, its outer
aperture two to three times as broad as the inner. Surface smooth.

Dimensions. — Length of the shell 0'22 to 0'28, breadth 0'2 to 0'25 ; inner mouth 0'04 to 0'08.
Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

4. Entocannula hirsuta, n. sp. (PI. 99, fig. 20).

Tricliogromia hirsuta, Haeckel, 1881, Manuscript.

Shell ovate. Pharynx cylindrical, one-fourth as broad as the shell, its inner and outer
apertures of equal breadth. The whole surface of the shell, and mainly the outer mouth, is densely
covered with thin, curved, siliceous bristles.

Dimensions. — Length of the shell 0'27 to 0'36, breadth 0'2 to 0'3 ; mouth 0'05 to 0'08.

Habitat. — North Atlantic, Fseroe Channel (Gulf Stream), John Murray, depth 600 fathoms.

Genus 697. Pharyngella,1 n. gen.

Definition. — Ch alle ngerida with a pharynx, and with one or more teeth on
the mouth, but without marginal spines.

The genus Pharyngella differs from the preceding Entocannula, its ancestral form,
in the development of one or more teeth on the peristome, and exhibits therefore the
same relation to it that Challengeria bears to Lithogromia. Only a few species of this
genus have been observed, all in the Atlantic.

1 Pharyngella = Shell with an internal pharynx.

1662 THE VOYAGE OF H.M.S. CHALLENGER.

1. Pharyngella monoceros, n. sp.

Shell ovate, slightly compressed, with a single large tooth on the dorsal corner of the peristome.
The tooth is cylindro-eonical, half as long as the shell, straight or slightly curved, and lies in the
main axis of the shell. Pharynx cylindrical, straight, half as long as the shell-radius. This species
is very similar to ChaUengeria tritonis (PL 99, fig. 5), and to the common cosmopolitan Challengeria
naresii, but differs generically from them in the possession of the pharynx.

Dimensions. — Diameter of the shell 0'25 to 0-28 ; length of the tooth 014.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

2. Pharyngella gastrula, n. sp. (PI. 99, fig. 18).

Shell ovate. Peristome with two parallel, vertical, straight, pointed teeth, which are half as
long as the shell-radius. Pharynx of the same length, cylindrical or funnel-shaped, its outer
aperture scarcely broader than the inner.

Dimensions. — Length of the shell 0'3 to 36, breadth 0'24 to 03; teeth and pharynx 0'07 to 0'09.

Habitat. — North Atlantic, Fseroe Channel (Gulf Stream), John Murray, depth 600 fathoms.

3. Pharyngella invaginata, n. sp.

Shell circular, slightly compressed or nearly spherical. Peristome with two parallel, vertical,
straight, pointed teeth, which are about as long as the shell-radius. Pharynx of the same length,
funnel-shaped ; its outer aperture twice as broad as the inner.

Dimensions. — Diameter of the shell 0'2 to 0'22, teeth and pharynx 0'05.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

4. Pharyngella gastrcea, n. sp. (PI. 99, fig. 17).

Shell broad, ovate or nearly circular, lenticular, strongly compressed. Peristome with two
parallel, pointed teeth, which are nearly as long as the shell-radius, slightly curved, and obliquely
inclined over the mouth. Pharynx half as long, cylindrical, obliquely descending ; its outer and
inner apertures of equal breadth.

Dimensions. — Diameter of the shell 0'3 to 0'33, teeth 0'12, pharynx 0'06.

Habitat. — South Atlantic, Stations 328 to 334, surface.

Genus 698. Porcupinia,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C hallengerida with a pharynx, with teeth on the mouth and
marginal spines.

The genus Porcupinia differs from the preceding Pharyngella in the development

1 Porcupinia, in memory of H.M.S. " Porcupine" by which the first British deep-sea explorations were carried out
during the years 1869 and 1870.

REPORT ON THE RADIOLARIA. 1663

of marginal spines, and exhibits therefore the same relation to it that Challengeron
bears to Challengeria. Only two species have been observed ; the first of these bears,
besides the large marginal spines, numerous flinty bristles on the surface of the shell.

1. Porcupinia aculeata, n. sp.

Shell ovate, one and one-third times as long as broad, slightly compressed, covered with short,
bristle-shaped spines over the whole surface, similar to Entocannula hirsuta (PL 99, fig. 20). The
keeled margin is armed with numerous long and stout radial spines, which are alternately larger
and smaller, as in Challengeron mosdeyi (PL 99, fig. 14) ; the larger about as long as the radius, the
smaller half as long. Peristorne with two straight, parallel teeth. Pharnyx funnel-shaped, half
as long as the radius, its outer aperture twice as broad as the inner.

Dimensions. — Length of the shell O24, breadth 0'18 ; peristome 0'05.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Porcupinia cordiformis, n. sp. (PI. 99, fig. 16).

Shell heart-shaped, nearly triangular, with a deep, concave bosom at the broad oral base, and a
bunch of five to nine divergent spines at the blunt aboral apex, the middle spine (in the main
axis) larger than the others. Peristome with two parallel, short, triangular teeth, which are
obliquely inclined over the mouth (their upper convex edge nearly horizontal). Pharynx cylindrical,
short, curved, and obliquely descending.

Dimensions. — Diameter of the shell 0'2 to 0'25, of the pharynx 0'05 to 0'08.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Family LXXIX. MEDUSETTIDA, n. fam. (Pis. 118-120).

Definition. — PH^EODARIA with a simple, ovate, hemispherical or cap-shaped lattice-
shell of peculiar alveolate structure, and with hollow articulate feet surrounding the
widely open mouth. Central capsule excentric, placed in the aboral half of the shell-
cavity.

The family Medusettida represents a peculiar group of remarkable PH^ODARIA,
which are similar to the Challengerida and Tuscarorida in the general form of the
monaxonian shell and its apophyses, but differ from both families in the strange alveolate
structure of the shell and of the hollow articulate feet surrounding its mouth. All the
forms of this family here described are new, and not a single species was known before
the discoveries of the Challenger. The majority seem to be inhabitants of the deep-
sea, and occur mainly in those places where other families of PH^EODAEIA (Aula-
canthida, Aulosphserida, Ccelodendrida) are also well represented ; they are, however,
nowhere so common as these latter families. Their long feet and the small delicate

1664 THE VOYAGE OF H.M.S. CHALLENGED

shell are extremely fragile, so that complete and well-preserved specimens are rare.
Some species are among the most admirable forms of Radiolaria, and are similar to small
elegant Medusae, e.g., Medusetta (PI. 120, figs. 1-4), Gazelletta (PI. 118, fig. 1), and
Gorgonetta (PI. 119).

The shell of the Medusettida is usually very small and delicate, in comparison to
the long, often exceedingly large, feet, which depend from the margin of its mouth.
From the size and the weight of these feet, we must suppose that the shell floats
in the water in the same position as in the NASSELLARIA, so that the main axis is
vertical, and the open mouth with the feet on its lower pole. The form of the shell
exhibits the same varieties as the similar umbrella of the Medusae. It is usually more
or less hemispherical, sometimes flatter, cap-shaped, at other times more highly vaulted,
campanulate or ovate. The similarity with the umbrella of a Medusa is so great, that in
many species the large lower opening on the mouth of the shell is surrounded by a
prominent ring or diaphragm, comparable to the velum of the Craspedotae or Hydro-
medusse (PI. 120, figs. 3-4).

The structure of the shell, which we term shortly " alveolate," is very remarkable,
and seems to be different from that of all the other PH.EODARIA. Its reticulate appear-
ance seems to indicate at first sight the usual lattice-shell, pierced by numerous very
small pores (PI. 118, figs. 1—3). But as soon as we make the shell dry, air always
enters into its thin walls, and each apparent pore is found to be a small alveole or a
separate compartment, which contains a small bubble of air (PI. 120, figs. 11, 16).
The thin wall of the shell is therefore double, composed of two parallel, very thin lamellae
of silica, which are little distant from one another, arid are connected by a network of
small rods or septa. This network is rarely regular, with square meshes (PI. 118, fig. 3),
or with hexagonal or triangular meshes ( PL 116, fig. 2); it is usually irregular, with
polygonal meshes (PL 120, figs. 11—16). The size of the meshes or alveoles is usually
smallest on the aboral apex of the shell, and increases 'gradually towards the mouth.
The largest alveoles are around the mouth, on the velum -shaped peristome, and here
the marginal alveoles of the shell pass directly over into the separate alveoles or hollow
compartments of the articulate feet (PI. 118, fig. 1). Probably each alveole is a separate
compartment, filled up by jelly, and has a small opening or pore on its inside ; this
pore is very distinct in the marginal alveoles of some larger species (PL 116, fig. la ;
PL 120, fig. 14), but I have not been able to recognise it everywhere. Moreover, it
often happens that the alveoles are apparently completely closed. In some smaller
species the alveolate structure seems to be present only in the peripheral part of the
shell, whilst the central part is solid.

The outer convex surface of the shell is usually smooth, sometimes papillate
(PL 116, fig. l), at other times studded with small, conical, radial spines (PL 118,
fig. 1 ; PL 120, figs. 4-11). Prolonged cylindrical spines or tubes are rarely

REPORT ON THE RADIOLARTA. 1665

scattered over the surface (PI. 116, figs. 1, 2). In some genera a long vertical or
oblique spine is developed from the apex of the shell, and is comparable to the " apical
horn of the NASSELLARIA (PI. 118, figs. 2, 3; PL 120, figs. 1-4).

The mouth of the shell, or the large opening on the lower pole of its vertical main
axis, is usually widely open, circular, or polygonal, more rarely constricted. In many
species the peristome is broadened and its margin developed in the form of a horizontal
diaphragm, which constricts the entrance into the shell-cavity, and is comparable to
the velum of the Hydromedusse (PL 120, figs. 1-4). Sometimes the margin of the
velum is fringed and bears numerous small dependent filaments of silica, comparable to
the marginal tentacles of many Medusae (PL 118, figs. 1, 3 ; PL 120, fig. 16). Rarely
the mouth is strongly constricted and prolonged into a narrow, long, cylindrical tube,
comparable to a proboscis ; its opening is usually fringed (PL 116, figs. 1, 2).

The hollow articulate feet, or the large radial apophyses of the peristome, are the
most remarkable organs of the Medusettida, and occur in the same form in no other
family of Radiolaria. Their number is variable, from three to twelve or more, and is
here employed for the distinction of genera, as it is rather constant ; the most frequent
number is four (Medusetta) or six (Gazelletta). The feet are usually cylindrical, much
longer than the shell, and more or less curved ; more rarely they are straight or
slightly compressed. They are always articulate, and divided by numerous transverse
parallel septa into hollow compartments or alveoles ; the transversely striated appearance
of the feet is brought about by these septa. The alveoles have usually the form of short
discoidal cylinders, and are broader than long (PL 120, figs. 5—13) ; rarely they are
longer than broad (fig. 15). The septa between the alveoles are always perforated
by a small opening, and usually this opening is prolonged into a shorter or longer
tubule, comparable to the siphuncle in the septa of the chambered shells of Cephalopoda ;
as in these latter, the succeeding siphons are arranged in a continuous series, which
lies either in the axis of the' foot or parallel to it (PL 120, figs. 8, 13, 15). The siphons
are directed towards the distal end of the foot, so that, e.g., the siphon which arises
from the septum between the ninth and tenth alveole, projects into the cavity of the
latter. The communicating cavities of all the alveoles are filled up by jelly. In the
dry shells, which are cleaned by hot mineral acids or by fire, and in which, therefore,
the jelly is destroyed, the cavities become easily filled by air-bubbles (PL 120, figs.
8, 11, 15). Whilst the alveoles of each foot always form a long simple series, this
series becomes doubled on the base of the larger feet, where they are broadened, and
pass over into the compartments of the peristome (PL 122, figs. 10, 11, 14). The
terminal alveole of each foot is closed.

The feet of the Medusettida are rarely quite simple and smooth (PL 120, figs.
1, 5, 7, 10, &c.). Usually they are armed with numerous spines or with elegant
pencils of spathillse. These secondary appendages or branches are also hollow, with a

(ZOOL. CHALL. EXP. PAKT XL. 1886.) Rr 209

1666 THE VOYAGE OF H.M.S. CHALLENGER.

thin wall of silex ; but they seem usually not to communicate with the alveoles of the
foot directly ; the cavities of the foot and its appendages are separated by a thin, solid
septum. In Medusetta the convex outer edge of each curved foot is studded with a
series of simple alveolate branches (PI. 120, figs. 2—4). In Gazelletta, the feet are
usually armed with verticillate or alternate spines, which are either simple or branched
(PI. 120, figs. 11-15) ; sometimes each branch is elegantly arborescent (PL 118, fig. 1).
Sometimes the distal end of each branch is armed with a spathilla or a coronet of
recurved teeth. The branches attain their highest development in the admirable
Gorgonetta (PL 119). The twelve feet of this most interesting genus are differentiated
into two different and alternating groups, six descending and six ascending. The six
upper or ascending feet are arborescent, and each branch is armed at the distal end with
a spathilla (figs. 1, 2). The six lower or descending feet are covered with most elegant
arborescent pencils or anchor-bearing trees ; each terminal branch of a tree is armed
with two spathillse, a smaller terminal and a larger below it (figs. 3, 4). The distal ends of
the feet are rarely simple, usually they are forked or branched, or armed with peculiar
spathillae ; and sometimes these terminal branches are very large (Pis. 118, 119).

The central capsule of the Medusettida is usually subspherical or somewhat lenticular,
and hidden in the aboral or upper part of the shell-cavity, whilst its oral or lower part
is filled up by the phseodium (PL 120, figs. 2, 9, 10, 11). Sometimes the phseodium
is very large and prominent at the aperture of the mouth (PL 118, figs. 2, 3 ; PL
119, fig. 1). The nucleus is usually ellipsoidal, half as large as the central capsule,
and includes numerous nucleoli. The membrane of the central capsule seems in all
Medusettida to possess only one opening, the astropyle or main-opening, with a radiate
operculum and proboscis, placed at the lower or oral pole (PL 120, fig. 2). I have
never been 'able to observe any secondary opening or parapyle. The free space between
the shell -wall and the capsule is filled up by the calymma, which also includes the
phseodium. The jelly of the calymma is probably in direct continuity with the jelly
which fills up the alveoles of the shell-wall and of the articulate feet.

Synopsis of the Genera of Medusettida.

I. Subfamily f Three equal feet, .... 699. Cortinetta.

Euphysettida.

Peristome of the shell with a corona of -j Four equal feet, .... 700. Medusetta.

three or four feet. Apex of the shell j
(usually) with an apical horn. [ One large and three small feet, . . 701. Euphysetta.

Six descending feet, .... 702. Gazelletta.
II. Subfamily

Gazellettida. Six descending and six ascending alternating

Peristome of the shell with six to twelve \ feet, ..... 703. Gorgonetta.

or more feet. Apex of the shell (usually)
without apical horn. Numerous (ten to twenty or more) descending

feet, . . . . 704. Polypetta.

REPORT ON THE RADIOLARIA. 1667

Genus 699. Cortinetta^ n. gen.
Definition. — M edusettida with three articulate feet on the peristome.

The genus Cortinetla comprises those Medusettida which exhibit the minimum
number of feet, three, and which therefore may be compared to the tripodal NASSELLARIA
(Cortina, Cortiniscus, Tripodiscus, &c.). This similarity is the greater, as in the few
observed species an apical horn is developed (as also in the following genus). The
three feet are in the two species observed of equal size and similar form, and equidistant,
so that they cannot be distinguished as an odd caudal and two paired lateral feet, as
in the similar NASSELLARIA.

1. Cortinetta tripodiscus, n. sp. (PI. 117, fig. 7).

Shell campanulate, covered with numerous curved ascending bristles, with a prominent annular
velum on the peristome, similar to that of Medusetta craspedota (PI. 120, fig. 4). Feet equal, widely
divergent and equidistant, somewhat longer than the shell, slightly curved, and covered on their
convex outer edge with a series of short lateral branches, the three ramules of which bear a spathilla.
Apical horn conical, straight, about as long as the shell, also covered with curved bristles.

Dimensions. — Length of the shell 014, breadth Oil; length of the feet 016, of the apical
horn Oil.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

2. Cortinetta cortiniscus, n. sp.

Shell campanulate, subspherical, thorny, with a prominent annular velum on the peristome.
Feet equal, very large, widely divergent, about three times as long as the shell and studded with
arborescent branches, similar to those of Gfazellctta drymonema (PL 118, fig. 1). Apical horn slender,
conical, straight, thorny, twice as long as the shell.

Dimensions. — Length of the shell 018, breadth 016 ; length of the feet 0'5 to 0'6, of the
apical horn 0'33.

Habitat. — Central Pacific, Station 274, depth 2750 fathoms.

Genus 700. Medusetta? n. gen.

Definition. — M edusettida with four equidistant articulate feet of equal size
on the peristome.

The genus Medusetta comprises those forms of the family which bear on the
peristome four equal radial feet, and therefore exhibit a striking similarity to many

1 Cortinetta,— Diminutive of Cortina. 2 Medusetta = Small Medusa.

1668 THE VOYAGE OF H.M.S. CHALLENGER.

small Medusae (e.g., Codonium, Tiara, Sarsia, &c.). This similarity is the greater, as
usually the four feet are elegantly curved and the entrance in the shell-cavity partly
closed by a marginal diaphragm, comparable to the velum of the Craspedotae or
Hydromedusse. In all the species observed the apex of the shell bears a slender vertical
or Curved spine, comparable to the apical horn of the NASSELLARIA. In most
species the feet bear on their convex outside a series of teeth or branches, which are
also alveolate.

1. Medusetta codonium, n. sp. (PL 120, fig. 1).

Shell ovate, smooth, twice as broad as the constricted mouth. Apical horn about as long as the
shell, nearly straight, smooth. Feet cylindrical, smooth, irregularly curved, about as long as the
shell.

Dimensions. — Length of the shell 0'08, breadth 0'05.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Medusetta tiara, n. sp.

Shell campanulate, smooth, about as long as broad, and three times as broad as the constricted
mouth, which is surrounded by a horizontal broad ring, like the velum of a Hydromedusa. Apical
horn conical, straight, half as long as the shell. Feet divergent, irregularly curved, twice as long
as the shell.

Dimensions. — Length of the shell 0'07, breadth 0'06.

Habitat. — North Atlantic (Fseroe Channel), John Murray, surface.

3. Medusetta minima, n. sp.

Shell slenderly ovate, smooth, about twice as long as broad, twice as broad as the constricted
mouth. Apical horn straight, vertical, of the same length. Feet somewhat longer, very thin,
slightly curved at the base, in the distal half nearly parallel and descending vertically.

Dimensions. — Length of the shell 0'06, breadth 0'03.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

4. Medusetta quadrigata, n. sp. (PL 120, fig. 2).

Shell ovate, campanulate, smooth, little broader than the wide open mouth. Apical horn
longer than the shell, more or less curved, smooth. Feet cylindrical, about as long as the shell,
strongly curved and somewhat spirally revoluted, with a series of short curved teeth on the
abaxial margin.

Dimensions. — Length of the shell 0'07 to 0'09, breadth 0'04 to 0'06.

Habitat. — North Pacific (off Japan), Stations 231 to 237, surface.

REPORT ON THE RADIOLARIA. 1669

5. Medusetta tetranema, n. sp. (PI. 120, fig. 3).

Shell campanulate, conical, smooth, nearly twice as broad as the constricted mouth, without
prominent velum. Apical horn somewhat shorter, straight, conical, thorny. Feet strongly curved
inwards, convergent, twice as long as the shell, each with four to six strong, ascending, alveolate
branches on the abaxial margin.

Dimensions. — Length of the shell 0'07 to 0'09, breadth 0'05 to 0'07.

Habitat. — Tropical Atlantic, Station 352, surface.

6. Medusetta spiralis, n. sp.

Shell hemispherical, thorny, with wide open mouth. Apical horn straight, vertical, thorny,
twice as long as the shell; feet cylindrical, three times as long as the shell, spirally convoluted around
the vertical axis of the shell, with a series of recurved teeth on the abaxial margin.

Dimensions. — Length of the shell 0'05, breadth 0'08.

Habitat. — Central Pacific, Stations 271 to 272, surface.

7. Medusetta craspedota, n sp (PI. 120, fig. 4).

Shell campanulate or nearly spherical, spiny, twice as broad as the constricted mouth, which is
surrounded by a funnel-shaped truncate velum. Apical horn conical, straight, spiny, half as long
as the shell. Feet strongly curved, longer than the shell, with a series of short conical spines on
the abaxial side.

Dimensions. — Length of the shell 0'06, breadth O06.

Habitat.-*- North Pacific, Station 239, surface.

Genus 701. Euphysetta,1 n. gen.

.Definition. — M edusettida with four articulate feet on the peristome, one odd
very large, and three small or rudimentary feet.

The genus Euphysetta agrees with the preceding Medusetta in the possession of
four articulate feet ; but whilst these in the latter are of equal size and similar shape,
in the former a single odd foot only is developed, and very large, whilst the three others
are rudimentary and very small. Euphysetta exhibits therefore the same relation to
Medusetta that the Euphysidse (Euphysa, Steenstrupia, &c.) bear to the Sarsiadse
(Codonium, Sarsia), among the Hydromedusse (compare my System der Medusen, 1879,
vol. i. p. 12).

1 Euphysetta = Diminutive of Euphysa (a Medusa).

1670 THE VOYAGE OF H.M.S. CHALLENGEK.

1. Euphysetta staurocodon, n. sp. (PI. 118, fig. 2).

Shell ovate, nearly as broad as long, smooth, with an oblique, slender, conical, apical horn of
the same length. The larger odd foot cylindrical, curved, somewhat longer than the shell, with
three diverging branches at the distal end. The three smaller feet very short, representing the form
of a regular rectangular cross.

Dimensions. — Length of the shell 015, breadth 014.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

2. Euphysetta hybocodon, n. sp.

Shell ovate, one and one-third times as long as broad, smooth, with an oblique, stout, conical
horn of half the length. The larger odd foot cylindrical, curved, twice as long as the shell, with a
few pairs of short lateral branches and forked distal end. The three smaller feet half as long as
the shell, thorny.

Dimensions. — Length of the shell 016, breadth 0'12.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

3. Euphysetta amphicodon, n. sp. (PL 118, fig. 3).

Shell subspherical, smooth, with a short, oblique, conical, apical horn. The larger odd foot
cylindrical, nearly straight, as long as the shell, with a few short lateral branches, at the distal
end forked. The three smaller feet were in one specimen observed forked, in another (the specimen
figured) replaced by nine small thorns.

Dimensions. — Length of the shell Oil, breadth 013.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 702. Gazelletta,1 John Murray, 1876 (in litteris).
Definition. — M edusettida with six articulate feet on the peristome.

The genus Gazelletta is by far the most common of all Medusettida, and some
species seem to be widely distributed, or even cosmopolitan. The number of species,
too, is in this genus much larger than in all the other genera of this family. It differs
from the latter in the possession of six feet, which number is very constant in the
majority of species ; in some species, however, single specimens are not rarely found
which possess five or seven feet instead of six. Usually the six feet are rather regularly
formed and disposed, and diverge downwards ; but sometimes there is more or less

1 Gazelletta = Named in memory of the German ship "Gazelle," which was engaged in deep-sea soundings during
the years 1874 to 1876, under the command of Captain Schleinitz (Naturalist, Professor Studer).

REPORT ON THE RADIOLARIA. 1671

irregularity in their shape and arrangement. In the majority of species the feet are very
long, curved, and armed in a very various manner, so that four subgenera may be dis-
tinguished, according to the armatures.

Subgenus 1. Gazellariu-m, Haeckel.
Definition. — Feet simple, smooth, without spines and without terminal branches.

1. Gazelletta hexanema, n. sp. (PI. 120, fig. 5).

Shell hemispherical, smooth. Feet very long, cylindrical, straight, smooth, widely divergent,
without terminal branches.

Dimensions. — Length of the shell 0'03 to 0'04, breadth 0'06 to 0'07; length of the feet 01 to 0'2.
Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific, surface.

2. Gazelletta macronema, n. sp. (PI. 120, figs. 7, 8).

Shell hemispherical, smooth. Feet very long, cylindrical, smooth, in the basal part horizontally
expanded, in the distal part strongly curved downwards, without terminal branches.
Dimensions. — Diameter of the shell 01 to 012, length of the feet T2 to T6.
Habitat. — Central Pacific, Stations 270 to 274, surface.

3. Gazelletta orthonema, n. sp. (PI. 120, fig. 10).

Shell hat-shaped, thorny. Feet cylindrical, straight, smooth, widely divergent, without
terminal branches.

Dimensions. — Diameter of the shell 012 to 016, length of the feet 0'3 to 0'5.
Habitat. — Central Pacific, Stations 270 to 274, surface.

4. Gazelletta cyrtonema, n. sp. (PI. 120, fig. 9).

Shell hat-shaped, thorny. Feet cylindrical, smooth, widely diverging at the base, strongly
curved and convergent in the distal part, often semicircular, without terminal branches.
Dimensions. — Diameter of the shell Oil to 013, length of the feet 04 to 0'6.
Habitat. — North Atlantic, Station 354, Canary Islands, surface.

Subgenus 2. Gazellidium, Haeckel.

-

Definition. — Feet smooth, without lateral spines, but branched at the distal end, or
with a bunch of terminal spines.

1672 THE VOYAGE OF H.M.S. CHALLENGER.

5. Gazelletta furcata, n. sp.

Shell flat, cap-shaped, smooth. Feet cylindrical, nearly straight, at the distal end forked, with
two divergent, spinulate, terminal branches.

Dimensions. — Length of the shell 012, breadth 0'3 ; length of the feet 0'6 to 0'8.
Habitat. — Western Tropical Pacific, Station 224, surface.

6. Gazelletta bifurca, n. sp. (PL 120, fig. 6).

Shell cap-shaped, thorny. Feet nearly straight, widely divergent, cylindrical, smooth, at the
distal end twice forked, with four divergent, terminal branches, each of which bears a spathillum
with six to eight recurved teeth (sometimes, as in the specimen figured, five or six terminal
branches instead of four).

Dimensions. — Diameter of the shell 01, length of the feet 0'3 to 04.

Habitat. — South Pacific, Station 288, surface.

7. Gazelletta penicillata, n. sp.

Shell campanulate, spiny. Feet cylindrical, strongly curved, smooth, with a bunch of twelve
to twenty or more curved spines at the distal end.

Dimensions. — Diameter of the shell 0'08, length of the feet 0'6.
Habitat. — Central Pacific, Station 266, surface.

Subgenus 3. Gazellonium, Haeckel.

Definition. — Feet spiny, armed with simple or branched lateral spines, and with
terminal branches of the same shape.

8. Gazelletta pectinata, n. sp.

Shell flat, cap-shaped, thorny, three times as broad as high. Feet straight or slightly curved,
cylindrical, widely divergent, with four longitudinal rows of short and simple conical spines, which
are directed towards the distal end, and about as long as a single joint of the foot.

Dimensions.- — Length of the shell 016, breadth 0'5 ; length of the feet 1/5 to 2'0, breadth 0'03
to 0-05.

Habitat. — North Atlantic, Fseroe Channel (John Murray), Hebrides (Mcebius).

9. Gazelletta pinnata, n. sp.

Shell hat-shaped, thorny. Feet cylindrical, strongly curved, pinnate, with two opposite longi-
tudinal rows of simple conical spines, which are slightly curved, directed towards the distal end and
opposed in pairs on about each third or fourth joint.

Dimensions. — Diameter of the shell 0'3, length of the feet 1/2 to To.

Habitat. — South Atlantic, Station 325, depth 2650 fathoms.

EEPORT ON THE RADIOLARIA. 167!

10. Gazelletta studeri, n. sp. (PL 120, fig. 15).

Shell flat, cap-shaped, thorny. Feet widely divergent, nearly straight and horizontally
expanded, with two alternate longitudinal rows of lateral spines, which arise perpendicularly from
the foot, are simple, conical, slightly curved, and alternate on the succeeding joints. Ends of the
feet constricted, with four to six spines in one row. Dedicated to Professor Studer.

Dimensions. — Diameter of the shell 015, length of the feet 0'6 to 0'8.

Habitat. — South Atlantic (east of Patagonia), Station 318, surface.

11. Gazelletta schleinitzii, n. sp. (PL 120, figs. 11, 12).

Shell hat-shaped, thorny. Feet cylindrical, nearly straight and horizontally expanded, with
four longitudinal rows of equal lateral spines, which arise perpendicularly from the foot and bear
at the end three short divergent teeth. The end of the arms bears three forked spines. I name
this elegant species in honour of Captain Schleinitz, commander of the German ship " Gazelle,"
who conducted the deep-sea soundings during the years 1874 to 1876. <

Dimensions. — Diameter of the shell 012, length of the feet 0~6 to 0'8.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

12. Gazelletta trispathilla, n. sp. (PL 120, fig. 13).

Shell flat, cap-shaped, smooth. Feet cylindrical, nearly straight, widely divergent, with longi-
tudinal rows of alternate spines, which arise perpendicularly from the foot and bear at the end
three short divergent branches, each with a spathilla of six short teeth.

Dimensions. — Diameter of the shell 0'2 to 0'25, length of the feet T2 to To.

Habitat. — North Pacific, Station 235 to 238, surface.

13, Gazelletta robusta, n. sp. (PL 120, fig. 14).

Shell flat, cap-shaped, thorny. Feet cylindrical, very stout, slightly curved, covered with short
irregularly branched spines ; their ends with a bunch of similar spines.
Dimensions. — Diameter of the shell 0'6, length of the feet 2'5 to 3'3.
HaMtat. — Central Pacific, Stations 263 to 274, surface.

Subgenus 4. Gazcllusiiim, Haeckel.

Definition. — Feet spiny, armed with simple or branched lateral spines, and with
larger terminal branches of a different shape.

(ZOOL. CHALL. EXP.— PART XL.— 1886.) Rr 210

1674 THE VOYAGE OF H.M.S. CHALLENGER.

14. Gazelletta dendronema, n. sp. (PI. 120, fig. 16).

Shell hemispherical, thorny, with a broad, alveolate velum which bears irregular hollow thorns
on the inside and on the free margin (fig. 16). Feet divergent, irregularly curved, with scattered
arborescent lateral spines, which are irregularly branched, and bear at the distal end of each branch
a small spathilla with four to six teeth. The distal ends of the feet are dichotomously branched,
with stouter simple fork-branches.

Dimensions. — Length of the shell 017, breadth 0'36 ; length of the feet O5 to 0'7.

Habitat. — North Pacific, Station 252, surface.

15. Gazelletta melusina, n. sp. (PI. 118, fig. 1).

Shell campanulate, spiny. Feet divergent, strongly curved, with scattered arborescent lateral
spines, which are richly and dichotomously branched, with thin, simple, terminal branches. The distal
ends of the feet bear three or four much larger and stouter branches, which are again dichotomously
branched.

Dimensions. — Length of the shell 0'2, breadth 015 ; length of the feet 0'5 to 0'8.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

Genus 703. Gorgonetta,1 n. gen.

Definition. — M edusettida with twelve articulate feet on the peristonie, six
ascending and six alternate descending.

The genus Gorgonetta is the most highly developed of all hitherto observed
Medusettida, and belongs to the most remarkable forms of Eadiolaria. Its general
shape is very similar to that of a larva of a Geryonia or Carmarina, in which six
interradial larval tentacles are directed upwards, six alternating • perradial permanent
tentacles downwards. The six ascending feet are in all the four species observed
smaller, more or less branched, and armed with spathillas. The six descending feet are
much larger and covered with very elegant pencils, the single threads of which bear
a double spathilla. The distal ends of the feet are forked or branched.

1. Gorgonetta mirabilis, n. sp. (PL 119, figs. 1-4).

Shell cap-shaped, flatly vaulted, or nearly hemispherical, about twice as broad as long, with
smooth surface. Six ascending feet widely divergent, about twice as long as the breadth of the
shell, nearly straight, arborescent, with numerous curved branches, each of which bears at the distal
end a spathilla with four to six short recurved teeth (fig. 2). Six descending feet about twice, as

1 Gorgonetta = Diminutive of Goryo, Medusa.

REPORT ON THE RADIOLARIA. 1675

long as the six alternate ascending, nearly straight, covered with numerous elegant pencils. Each
pencil is richly branched, with fifty to one hundred or more thread-like raimiles, and each terminal
ramule has two cruciate spathillse, a larger proximal and a smaller distal (figs. 3, 4) ; the four
recurved anchor-teeth of the proximal spathilla are twice as large as those of the distal. The
distal end of each descending foot bears three or four very stout terminal branches, each of which
is about as long as the shell and again trifurcate at the distal end.

Dimensions. — Length of the shell 0'2 to 0'3, breadth 0'4 to 0'5.

Habitat. — Tropical Atlantic, Stations 346 to 348, surface.

2. Gorgonetta geryonia, n. sp.

Shell hemispherical, twice as broad as long, with short scattered thorns on the surface. Twelve
feet of similar shape to those in the preceding species, but differing in the following characters : — the
six ascending feet are much smaller, about as long as the breadth of the shell, and each bears only
six to twelve short branches ; the six descending feet are about three times as long as the shell,
more or less curved ; their pencils much smaller, and the two spathillae of each pencil-thread bear
five anchor-teeth. The distal ends are more richly and irregularly branched.

Dimensions. — Length of the shell 0'4, breadth 0'7.

Habitat. — Indian Ocean (Cocos Islands), Rabbe, surface.

3. Gorgonetta carmarina, n. sp.

Shell flat, cap-shaped, three times as broad as long. Twelve feet similar in shape to those of
the two preceding species, but more irregular in form and arrangement, and differing in the following
characters : — the six ascending feet are nearly horizontally expanded, one and a half times as long
as the breadth of the shell, with few short branches, each of which bears a spathilla with six
recurved anchor-teeth. The six descending feet are about five times as long as the shell, irregularly
curved, studded with numerous small pencils, each thread of which bears a double spathilla with
six teeth. The distal ends are irregularly branched.

Dimensions. — Length of the shell O2, breadth 07.

Habitat. — South Pacific, Station 318, depth 2040 fathoms.

4. Gorgonetta bisenaria, n. sp.

Shell campanulate, similar to that of Gfazelletta melusina (PI. 118, fig. 1), with smooth surface.
Six ascending feet about as long as the shell, nearly straight, similar to those of Gorgonetta mirdbilis
(PI. 119, fig. 1). Six descending feet also similar to those of the latter, but shorter, about twice as
long as the shell, strongly curved, studded with numerous small pencils, each thread of which has
a double spathilla with three teeth. The distal end of each foot bears a whorl of six to eight
irregular forked branches.

Dimensions. — Length of the shell 0'5, breadth 0'4.

Habitat. — Central Pacific, Station 263, surface.

1676 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 704. Polypetta?- n. gen. '

Definition. — M edusettida with numerous (ten to twenty or more) articulate
feet.

The genus Polypetta comprises those Medusettida in which the number of feet is
very large and not limited, usually twenty to thirty or more. The few specimens of
this genus that have been observed are rather different ; and it may be that only the
two first species described in the following lines are true Medusettida ; they possess
the usual distinctly alveolate feet, and are derived from the similar Medusetta or
Gazelletta simply by multiplication of the feet. The two other species, however
(figured in PL 116, figs. 1, 2, as Porospathis), belong perhaps to another family of
PH^EODAKIA (Castanellida?); their shell-structure is peculiar and their feet not distinctly
alveolate ; they may therefore represent a peculiar genus Porospathis (Haeckel,
Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12, 1879, p. 5).

1. Polypetta polynema, n. sp.

Shell campanulate, thorny, about as long as broad, with slightly constricted mouth, similar to
that of Gazelletta orthonema (PL 120, fig. 10). Shell-wall hollow, with irregular polygonal alveoles.
Peristome with a corona of eighteen divergent, curved, cylindrical feet of unequal size ; six larger
primary on the margin of the shell, the other twelve secondary, between the former, somewhat
above the margins at different heights. The feet are two to three times as long as the shell, irregu-
larly curved and distinctly alveolate, without appendages.

Dimensions. — Length of the shell 0'12, breadth O'll.

Habitat. — Central Pacific, Station 266, surface.

2. Polypetta alveolata, n. sp.

Shell campanulate, thorny, about as long as broad, very similar to that of Medusetta craspedota
(PL 120, fig. 4). Shell- wall hollow, with subregular hexagonal alveoles. Peristome prolonged into
a short funnel-shaped proboscis, twice as long as the similar velum of the latter. The velum is
surrounded by a corona of eight larger and eight to twelve smaller feet ; the larger are about as
long as the shell, divergent, irregularly curved, thorny, and distinctly alveolate ; the smaller feet
are scattered above the latter and form an immediate transition to the small spines of the shell-
surface.

Dimensions. — Length of the shell 0'08, breadth 0-09.

Habitat. — South Pacific, Station 284, surface.

1 Polypetta — Diminutive of Polypus.

REPORT ON THE RADIOLARIA. 1677

3. Polypetta tabulata, n. sp. (PL 116, figs. 2, 2a, 26).

PorospatMs tabulata, Hseckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12.

Shell subspherical, with elegantly panelled or tabulate surface, composed of small triangular
plates, which are separated by a network of prominent crests ; at each nodal point of the network a
small conical thorn arises (figs. 2«, 2i). Each triangular plate seems to contain a hollow alveole, which
opens into the shell-cavity (?). On the surface of the shell are scattered numerous (thirty to forty
or more), cylindrical, hollow, radial spines, which are straight or slightly curved, not distinctly
alveolate, and increase in size towards the mouth. The aboral spines are scarcely one-third as long
as the radius of the shell, whilst the oral spines are three times as long as its diameter. The pro-
boscis of the constricted mouth is a hollow cylinder, longer than the shell-radius, and armed with
a corona of fifteen to twenty slender bristle-shaped teeth. The position of this singular species in
this family is doubtful.

Dimensions. — Diameter of the shell O'l to Oil, length of the peristome O'OY, breadth 0'02.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

4. Polypetta mammillata, n. sp. (PL 116, figs. 1, la).

Porospathis mammillata, Hrcckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12.

Shell subspherical, densely covered with numerous mammiliform hollow papillae, between which are
scattered single longer, hollow, radial spines ; these are irregularly curved, cylindrical, without distinct
alveoles ; the twelve longest are two to three times as long as the shell, divergent in the oral direc-
tion, and surround the base of the peristome in two irregular alternate circles, each with six spines.
The hollow papillae of the surface, between which are placed numerous circular pores (or dimples ?),
open into the shell-cavity by a small pore (fig. la) ; they are perhaps reduced radial spines. The
constricted peristome is conical and prolonged into an inversely conical proboscis, which is about as
long as the radius of the shell ; its dilated mouth is surrounded by a corona of slender, divergent,
bristle-shaped teeth. The position of this species in the family Medusettida is doubtful ; perhaps
it is more closely allied to the Castanellida.

Dimensions. — Diameter of the shell 0-12 ; length of the proboscis O'OS, breadth O'OS ; length of
the shorter spines O'l, of the longest spines 0'3.

Habitat. — North Pacific, Station 252, surface.

Family LXXX. CASTANELLIDA, Haeckel, 1879 (PL 1 13).

Castanellida, Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12, p. 5.

Definition. — PH^ODARIA with a spherical or subspherical shell, exhibiting ordinary
lattice-work, with circular or roundish pores. Radial spines without circles of basal
pores. Mouth of the shell large, usually circular and armed with teeth. Central
capsule excentric, placed in the aboral half of the shell-cavity.

1678 THE VOYAGE OF H.M.S. CHALLENGER.

The family Castanellida represents a common and widely distributed group of
PH^ODARIA, which possess a very simple and uniform shell, viz., a simple lattice -sphere
with radial spines and one simple mouth. It may therefore be easily confounded with
the Coscinommida, or those Sphseroidea in which the shell is also a simple lattice-
sphere armed with radial spines (Astrosphcerida simplicia, p. 209). Indeed the shell
of both groups is very similar, and differs in one important point only ; the Castanellida
constantly possess one larger opening in the shell-wall, the shell-mouth, which is either
smooth or armed with a corona of teeth ; in the Coscinommida, however, such a mouth
is never present. The living specimens of both groups, and those shells in which the
soft body is preserved, are very easily distinguished, since the shell encloses in the
Coscinommida the central capsule and the transparent calymma only, whilst the latter,
besides, in the Castanellida contains a voluminous dark brown or green mass of
phseodella, the characteristic phseodium. A closer examination of the central capsule
reveals in all Castanellida the typical operculum, the astropyle, with the proboscis
of the PH.EODARIA, which is never present in any Sphseroidea.

The Castanellida are easily distinguished also from those similar PH/EODARIA in
which the shell is also a lattice-sphere ; the lattice-work is constantly quite simple, as
in the similar Coscinommida, never composed of separated tangential pieces (as in the '
A.ulospha3rida), or of porcellanous structure, with basal circles of pores (as in the
Circoporida), or of diatomaceous structure (as in the Challengerida). The gigantic
OrosphaBrida, which also in part possess a simple lattice -sphere, differ from the
Castanellida in the absence of the peculiar shell-mouth.

Though the Castanellida belong to the most common PH^ODARIA, and though the
number of individuals, floating on the surface of the tropical seas, is extraordinarily
great, their variety of forms is very small; the six genera distinguished in the following
system differ only in very slight characters, and the majority of the species are very
similar, and often hardly distinguishable. The seven species figured in PL 113
exhibit the most striking differences which I could distinguish among all the species
observed. The shell usually has the characteristic appearance of a chestnut, a sphere
covered with very numerous short radial spines or bristles. In the majority of species
a certain number of longer thin radial spines is scattered over the surface ; these
are usually simple, rarely branched. The mouth of the shell, corresponding to the
proboscis of the central capsule, and placed in the same radius, is either a quite
simple larger opening with a smooth margin (figs. 3, 5, 7) or is armed with a corona of
teeth (figs. 1, 6).

The size of the shell varies between 0-2 and 0'8 mm., and is usually between 0'3
and 0-5 mm. Its form is in the majority of species a geometrical sphere ; rarely it is
somewhat irregular, slightly ellipsoidal (prolonged in the axis of the mouth and
proboscis), or polyhedral (by conical protuberances from the bases of the radial spines).

REPORT ON THE RADIOLARIA. 1679

The ideal fundamental form of the shell, however, is constantly monaxonian, since the
place of the shell-mouth and of the proboscis of the capsule (both lying in one axis of
the sphere), causes a principal axis to be different from all others. The longer radial
spines, quite variable in number and disposition, are never arranged regularly or
symmetrically, and therefore determine no constant axes.

The lattice-work of the spherical shell offers also but slight differences. It is
usually more or less irregular, with circular or subcircular pores of unequal sizes. More
rarely the network is perfectly regular, with equidistant circular pores of equal size,
and sometimes these are surrounded by hexagonal frames (fig. 6), as in many
Sphseroidea. More rarely the pores are perfectly irregular, roundish or sometimes
polygonal, of unequal sizes and dissimilar forms (fig. 2). The size of the pores is very
variable, between O'Ol and 0'05, usually between G'015 and 0'025. They are commonly
somewhat broader than the bars between them, more rarely smaller. The substance of
the shell-wall is in the majority of Castanellida hyaline, transparent (as in the similar
Sphseroidea); in some larger forms, however, a network of fine axial filaments is
visible in the lattice (fig. 2), and sometimes this seems to be hollow, with an axial
canal (as in the large Orosphserida). Such an axial filament or fine axial canal is
usually visible in the larger radial spines. The shell-wall of the Castanellida, however,
never exhibits that characteristic structure (with tangential needles in a cement-
like fundamental substance), which we find in all Circoporida. The latter differ also in
the constant presence of circles of large pores around the bases of the radial spines,
which are never found in the Castanellida. The shell becomes usually stained more or
less purple by carmine, and when burned by fire, becomes of a brown colour.

The inner surface of the shell is always quite smooth, the outer surface armed
with numerous short and thin radial bristles. Sometimes these bristles or " by-spines "
are very short, but never perfectly wanting. Usually their length is about one-third
or one-fourth of the radius of the shell, often less, rarely more. They arise from the
nodal points between every three or four neighbouring spines, and are commonly very
thin and straight, pointed, with slightly thickened conical basis. Rarely they are
directed not quite radially, but more or less obliquely.

The larger radial spines, which arise between the thin bristles or " by-spines " and
may be opposed to the latter as " main-spines," are wanting in two genera only, in
Castanarium and Castanella (PL 113, fig. 6). They are simple in Castanidium
(figs. 2, 5, 7) and Castanissa (fig. 1), irregularly branched in Castanopsis and
Castanura (figs. 3, 4). Their number and disposition is never regular nor symmetrical
(as in the majority of Sphseroidea) and varies even in each single species. In
general the number of main-spines varies between ten and forty (rarely less or more)
usually between twenty and thirty. Their length is commonly about equal to the
diameter of the shell, often somewhat shorter, rarely considerably longer. Their

1680 THE VOYAGE OF H.M.S. CHALLENGER.

thickness is in the majority of species about equal to the diameter of one or two pores
of the lattice. Sometimes they are much stronger, rarely thinner.

The form of the radial main-spines is not very variable, usually it is cylindrical or
cylindro-conical, rarely angular, prismatic or pyramidal. Sometimes they are straight
(perfectly radial), at other times more or less irregularly curved. Usually they are
simple, rarely branched ; the branches are always very irregular and exhibit a remark-
able tendency to unite by concrescence (figs. 3, 4). Some thicker forms of spines
exhibit a remarkable structure, the surface being covered with small dimples and
spinules between them (fig. 1); sometimes the dimples are hexagonal (fig. 5«). In
the axis of the thicker spines there is often visible the same axial filament or funicle
which we find in many other PH^EODAKIA, more -rarely a hollow axial canal.

The mouth of the shell is usually circular, more rarely polygonal or irregularly
roundish (fig. 2). It is either quite smooth (figs. 3, 5, 7) or armed with a corona of
strong teeth (figs. 1, 4, 6). These teeth are different from the other spines of the
shell ; they are much thicker than the radial bristles, and shorter than the main-spines.
Their number varies between three and twenty, usually between five and seven. They
are usually parallel to the main axis, which is determined by the excentric position of
the mouth and the centre of the sphere (figs. 1, G). The teeth are usually conical,
more or less irregular in size and form, more rarely of equal size. The corona of teeth
is usually sharply separated from the surrounding lattice-work of the shell, but has no
influence on its regular spherical form.

The central capsule of the Castanellida immediately determines beyond doubt their
true PH^EODARIAN nature ; it lies excentrically in the cavity of the enclosing shell,
and is surrounded at the oral pole by the large and dark phseodium. The latter covers
the radiate operculum of the capsule membrane and the tubular proboscis, which arises
from it and is directed towards the shell mouth. Usually the diameter of the spherical
central capsule is about one-third of the shell diameter, rarely one-quarter only, and in a
few cases it attains nearly its half. The calymma, therefore, is larger than the capsule,
and fills up the whole cavity of the shell which is not occupied by the latter. The
greater part of the calymma again is filled up by the dark green or brown, sometimes
black phseodella, the roundish granules which compose the voluminous non-transparent
phgeodium. Sometimes the latter proceeds through the mouth and is partially placed
outside the shell (fig. 5).

The astropyle, or the main-opening of the central capsule, is placed on the oral pole of
its main axis, while its radiate operculum and the tubular proboscis arising from it possess
the same structure as in the other PH^ODARIA. But the two lateral parapylse or accessory
openings which are present in the majority of the latter seem to be absent in the
Castanellida as well as in the Medusettida and the Challengerida. I could never observe
a trace of them. The proboscis is a small cylindrical tube and is directed towards the

EEPORT ON THE RADIOLARIA. 1681

mouth of the shell, therefore placed in its main axis ; it is usually quite hidden in the
dark phseodium, which occupies the oral half of the shell-cavity, whilst the capsule lies
in the aboral half, The large nucleus of the central capsule and its double membrane
present the same characters as in the other PH^EODARIA.

Synopsis of the Genera of Castanellida.

,., . . /. ,,.,. . I Mouth smooth, . 705. Castanarium.

No long radial main-spmes (in addition to the constant J

short bristles of the sheU-suiface). | Mouth ^^ _ _ 7Q6_

Long radial main-spines
scattered between the short
constant bristles of the "
shell-surface.

Main spines simple.

Mouth smooth, . . 707. Castanidium.

Mouth dentate, . . 708. Castanissa.

Mouth smooth, . . 709. Oastanopsis.

Main spines branched.

Mouth dentate, . .710. Castanura.

Genus 705. Castanarium,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C astanellida without radial main-spines, with a simple smooth
mouth.

The genus Castanarium is the simplest form of all the Castanellida, and may be
regarded as the common ancestral form of this family. The simple spherical shell has a
smooth, toothless mouth and no larger radial spines; it is densely studded with the
simple, radial bristles, which are common to all Castanellida. The shell therefore is
very similar to those species of the Astrosphseride Acanthosphcera, which represent the
subgenus Rhapidococcus (compare above, p. 210, PL 26, fig. 3); it differs from the
latter in the possession of the shell-mouth, which is absent in all S p h ae r o i d e a.

1. Castanarium darwini, n. sp.

Pores regular, circular, hexagonally framed, three times as broad as the bars. Radial bristles
half as long as the radius.

Dimensions. — Diameter of the shell 0'3 to 0'4, of the pores 0'03.

Habitat. — South Atlantic (east of Patagonia), Station 318, depth 2040 fathoms.

1 Castanarium = Shell similar to a chestnut, Costarica.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 211

1682 THE VOYAGE OF H.M.S. CHALLENGER.

2. Castanarium hookeri, n. sp.

Pores regular, circular, hexagonally framed, twice as broad .as the bars. Eadial bristles one-
third as long as the radius.

Dimensions. — Diameter of the shell 0'55, of the pores 0-025.
Habitat. — Indian Ocean, Cocos Islands (Eabbe), surface.

3. Castanarium lyelli, n. sp.

Pores regular, circular, without hexagonal frames, of the same breadth as the bars. Radial
bristles twice as long as the diameter of one pore.

Dimensions. — Diameter of the shell 0'24, of the pores 0'015.
Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

4. Castanarium lubbocki, n. sp.

Pores irregularly roundish, about of the same breadth as the roundish, non-crested bars. Eadial
bristles one-third as long as the radius.

Dimensions. — Diameter of the shell 0'36, of the pores O'Ol to 0'02.
Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

5. Castanarium huxleyi, n. sp.

Pores irregularly polygonal, two to three times as broad as the bars, separated by prominent
polygonal crests. Eadial bristles half as long as the radius.

Dimensions. — Diameter of the shell 0'45, of the pores 0'02 to 0'05.
Habitat. — South Pacific (off Australia), Station 165, surface.

Genus 706. Castanella,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C astanellida without radial main-spines, with a dentate mouth.

The genus Castanella comprises the most common and most widely distributed
species of Castanellida. It agrees in general shape with its ancestral form, the
preceding Castanarium, differing from it only in the possession of strong teeth, which
form a corona around the mouth.

1 Castanella = Diminutive of Costarica.

REPORT ON THE RADIOLARIA. 1683

1. Castanella wyvillei, n. sp. (PI. 113, fig. 6).

Pores regular, circular, of equal size, hexagonally framed, of the same breadth as the bars.
Eadial bristles twice as long as the diameter of one pore. Mouth with five to six parallel, conical
strong teeth, which are twice as long as a bristle (fig. 6a).

Dimensions. — Diameter of the shell O5 to 0'7, of the pores 0'02 to 0'03.

Habitat. — North Pacific, Stations 252 to 256, surface.

2. Castanella thomsoni, n. sp.

Pores regular, circular, of equal size, hexagonally framed, twice as broad as the bars. Eadial
bristles about as long as the diameter of one pore. Mouth with four strong, conical teeth, forming a
regular cross, four times as long as a bristle.

Dimensions. — Diameter of the shell 0'7 to 0-8, of the pores 0'03.

Habitat. — South Pacific, Stations 295 to 298, surface.

3. Castanella campbelli, n. sp.

Pores regular, circular, hexagonally framed, three times as broad as the bars. Eadial bristles
half as long as the radius of the shell Mouth with a coronet of eight conical, parallel teeth, of the
same length as the bristles, but four to six times as thick.

Dimensions. — Diameter of the shell 0'4 to 0'45,'of the pores 0'025.

Habitat. — Central Pacific, Stations 270 to 274, surface.

4. Castanella sloggetti, n. sp.

Pores subregular, circular, without frames, of different sizes, about twice as broad as the bars.
Eadial bristles three times as long as one pore. Mouth with five or six strong, conical teeth, twice
as long as the bristles.

Dimensions.— Diameter of the shell 0'3 to 0'36, of the pores 0'02 to 0'03.

Habitat. — Tropical Atlantic, Stations 347 to 349, surface.

5. Castanella balfouri, n. sp.

Pores irregular, roundish, two to three times as broad as the bars. Bristles about one-fourth
as long as the radius. Mouth with four strong conical teeth, forming a cross, somewhat longer and
much thicker than the bristles.

Dimensions. — Diameter of the shell 0'22 to 0'28, of the pores O'Ol to 0'02.

Habitat. — North Pacific, Stations 240 to 245, surface.

1684 THE VOYAGE OF H.M.S. CHALLENGER.

6. Castanella channeri, n. sp.

Pores irregular, roundish, two to four times as broad as the bars. Bristles nearly half as long
as the radius. Mouth with seven to nine short conical teeth, shorter than the bristles, but much
thicker.

Dimensions. — Diameter of the shell 0'3 to 0'4, of the pores 0'02 to O025.

Habitat. — North Atlantic, Stations 352 to 354, surface.

7. Castanella horstoni, n. sp.

Pores irregular, polygonal, three to four times as broad as the bars. Bristles about as long as the
radius. Mouth with six stout pyramidal teeth, which are scarcely one-third as long as the radius.
Dimensions. — Diameter of the shell O55, of the pores 0'02 to 0'025.
Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 707. Castanidium? Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C astanellida, with simple radial main-spines and a simple smooth
mouth.

The genus Castanidium agrees with its ancestral form Castanarium in the simple
shape of the smooth and toothless mouth, but differs from it in the possession of long
radial main-spines, which are scattered between the constant radial bristles or by-spines
of the surface. The shell agrees therefore in its general shape with the Astrosphseride
Heliosphcera, as defined above (p. 217, PI. 26, fig. 9), but differs from it in the pos-
session of the shell -mouth wanting in all Sphseroidea.

•

1. Castanidium willemoesi, n. sp.

Pores regular, circular, hexagonally framed, twice as broad as the bars. Bristles three times
as long as the diameter of one pore. Eadial main-spines straight, conical, smooth, as long as the
radius.

Dimensions. — Diameter of the shell 0'3 to 0'4, of the pores 0-012 to O'OIG.

Habitat. — Central Pacific, Station 263 to 274, surface.

2. Castanidium wildi, n. sp.

Pores regular, circular, hexagonally framed, of the same breadth as the bars. Bristles twice as
long as one pore. Eadial main-spines straight and short, cylindrical, with dimpled surface (as in
PI. 113, fig. 1), as broad as one pore and as long as the diameter of the shell.

Dimensions. — Diameter of the shell 0'66, of the pores 0'045.

Habitat. — South Pacific, Station 297, surface.

1 Castanidium = Small chestnut ; *«<;T«>iS(ov.

REPORT ON THE RADIOLARIA. 1685

3. Castanidium buchanani, n. sp. (PL 113} fig. 7).

Pores regular, circular, without frames, twice as broad as the bars, of variable size. Bristles
five to six times as long as one pore. Eadial main-spines numerous, straight, slender, cylindrical,
about as long as the diameter of the shell.

Dimensions. — Diameter of the shell 0'25 to 0'3, of the pores O012 to 0'02.

Habitat. — Tropical Atlantic, Stations 346 to 349, surface.

4. Castanidium murrayi, n. sp. (PL 113, figs. 5, 5a).

Pores subregular, circular, without frames, three times as broad as the bars. Bristles three
times as long as one pore. Eadial main-spines cylindrical, stout, irregularly curved, longer than
the shell-diameter, covered with longish hexagonal dimples, which are separated by a network of
prominent crests (fig. 5a).

Dimensions. — Diameter of the shell 0'4 to O'o, of the pores 0'02 to 0'025.

Habitat. — North Atlantic, Station 352 to 354, surface.

5. Castanidium aldrichi, n. sp.

Pores subregular, circular, without frames, of variable size, about as broad as the bars. Bristles
four times as long as one pore. Radial main-spines conico-cylindrical, irregularly curved, straight,
about as long as the radius. (The conical base of the spines is inflated and fenestrated, therefore
the shell is nearly polyhedral.)

Dimensions. — Diameter of the shell 0-35 to 0'4, of the pores 0'012 to 0'015.

Habitat. — Central Pacific, Stations 270 to 274, surface.

6. Castanidium bromleyi, n. sp.

Pores irregular, roundish, two to four times as broad as the bars. Bristles half as long as the
radius. Radial main-spines cylindrical, straight, slender, longer than the shell- diameter.
Dimensions. — Diameter of the shell 0'22 to 0'26, of the pores 0'006 to 0'02.
Habitat. — Indian Ocean and Southern Pacific, Stations 162 to 169, surface.

7. Castanidium bethelli, n. sp.

Pores irregular, roundish or polygonal, two to three times as broad as the bars. Bristles one-
third as long as the radius. Radial main-spines conico-cylindrical, irregularly curved, with dimpled
surface, somewhat longer than the radius.

Dimensions. — Diameter of the shell 0'5 to 0'6, of the pores 0'015 to 0'03.

Habitat. — North Pacific, Stations 235 to 245, surface.

1686 THE VOYAGE OF H.M.S. CHALLENGEE.

8. Castanidium moseleyi, n. sp. (PI. 113, fig. 2).

Pores -irregular, roundish or polygonal, two to four times as broad as the bars. Bristles about
as long as the diameter of one pore, or a little longer. Eadial main-spines cylindrical, irregularly
curved, somewhat longer than the diameter of the shell ; their base is more or less inflated and
fenestrated, therefore the shell is nearly polyhedral

Dimensions. — Diameter of the shell 0'7 to 0'8, of the pores O'Ol to 0'04.

Habitat. — Tropical Atlantic, Stations 346 to 349, surface.

Genus 708. Castanissa,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C as t an ell i da with simple radial main-spines and a dentate
mouth.

The genus Castanissa agrees with the preceding Castanidium in the possession of
large radial main-spines, scattered between the numerous bristles or by-spines of the
surface ; but it differs from it in the possession of teeth around the mouth, identical
with those of Castanella ; it may be derived therefore either from the latter by
development of main-spines, or from the former by formation of teeth.

1. Castanissa challengeri, n. sp. (PI. 113, fig. 1).

Pores regular, circular, three times as broad as the bars. Bristles one-fourth as long as the
radius. Eadial main-spines (about twelve) very stout, straight, cylindrical, at the distal end
conical, pointed, with dimpled surface, about half as long as the radius. Mouth very large, circular,
about one-third as broad as the shell, with a corona of twelve to sixteen very large, triangular,
parallel teeth.

Dimensions. — Diameter of the shell 0'7 to 0'8, of the pores 0'03.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Castanissa pearceyi, n. sp.

Pores regular, circular, twice as broad as the bars. Bristles half as long as the radius. Eadial
main-spines (about twenty) slender, cylindrical, smooth, irregularly curved, about as long as the
radius. Mouth large, half as broad as the radius, with a corona of ten to twelve irregular, slender
teeth.

Dimensions. — Diameter of the shell 0'5 to 0'6, of the pores 0'02.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

1 Castanissa = Dimiuutive of Castanea.

REPORT ON THE RADIOLARIA. 1687

3. Castanissa richardsi, n. sp.

Pores subregular, circular, about as broad as the bars. Bristles twice as long as one pore.
Radial main-spines (about twenty) slender, cylindrical, irregularly curved, with dimpled surface (like
those in PI. 113, fig. 5a). Mouth with a corona of six stout, parallel, triangular teeth.

Dimensions. — Diameter of the shell 0'3 to 0'35, of the pores 0'015.

Habitat. — North Atlantic, Station 354, surface.

4. Castanissa crosbiei, n. sp.

Pores irregular, roundish, two to three times as broad as the bars. Bristles one-third as long
as the radius. Eadial main-spines very numerous, straight, cylindrical, smooth, about as long as
the diameter of the shell. Mouth with ten or twelve irregular, conical, parallel teeth.

Dimensions. — Diameter of the shell 0'28, of the pores O'Ol to 0'015.

Habitat. — North Pacific, Stations 231 to 235, surface.

5. Castanissa macleani, n. sp.

Pores irregular, roundish or polygonal, two to four times as broad as the bars. Bristles about
one-fourth as long as the radius. Eadial main-spines numerous, straight, conical, stout, with
dimpled surface, shorter than the radius. Mouth with six to eight irregular conical teeth.

Dimensions. — Diameter of the shell 032, of the pores 0'012 to 0'024.

Habitat.- — Tropical Pacific, Station 268, depth 2900 fathoms.

6. Castanissa hoylei, n. sp.

Pores irregular, polygonal, two to three times as broad as the bars. Bristles nearly half as
long as the radius. Eadial main-spines (about thirty) very long and thin, cylindrical, irregularly
curved, at the conical base inflated and fenestrated ; shell therefore slightly polyhedral. Mouth
with five strong conical teeth.

Dimensions. — Diameter of the shell 0'35 to 0'4, of the pores 0'02 to 0'03.

Habitat. — North Pacific, Station 245 to 250, surface.

Genus 709. Castanopsis,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — Cas tanellida with branched radial main-spines and a simple
smooth mouth.

The genus Castanopsis differs from its ancestral form Castanidiutn in the ramifica-
tion of the radial main-spines ; the branches are usually very irregular and often partly

1 Castanopsis = Shell similar to a chestnut ; xciimti/o>i, Ifyis.

1688 THE VOYAGE OF H.M.S. CHALLENGER.

confluent. The shell is very similar to the Astrosphseride Cladococcus (compare above
p. 223, PI. 27), but differs from it in the possession of the shell-mouth, absent in all
Sphseroidea.

1. Castanopsis naresi, n. sp. (PI. 113, fig. 3).

Pores subregular, circular, about twice as broad as the bars. Bristles twice as long as one
pore. Eadial main-spines somewhat shorter than the diameter of the shell, straight, cylindrical, in
the proximal half simple, in the distal half irregularly branched, each with ten to twelve partly
confluent branches.

Dimensions. — Diameter of the shell 06 to 0'7, of the pores 0'02 to 0'03.

Habitat. — Tropical Atlantic, Station 347 to 349, surface.

2. Castanopsis macleari, n. sp.

Pores irregular, roundish, two to four times as broad as bars. Bristles half as long as the
radius. Eadial main-spines about as long as the radius, stout and straight, cylindrical, forked
at the distal end, with two or three unequal fork-branches.

Dimensions. — Diameter of the shell 0'42, of the pores 0'015 to 0'03.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

3. Castanopsis fergusoni, n. sp.

Pores irregular, roundish or polygonal, about as broad as the bars. Bristles three times as long
as one pore. Radial main-spines somewhat longer than the diameter of the shell, cylindrical, with
irregular and partly confluent lateral branches (similar to PI. 113, fig. 4a).

Dimensions. — Diameter of the shell 0'55, of the pores 0'012 to 0'016.

Habitat. — North Atlantic, Station 354, surface.

Genus 710. Castanura,1 Haeckel, 1879, Sitzuugsb. med.-nat. Gesellseh. Jena,

Dec. 12, p. 5.

Definition. — C astanellida with branched radial main-spines and a dentate
mouth.

The genus Castanura differs from the preceding Castanopsis in the possession of a
corona of teeth surrounding the mouth, similar to that of Castanissa. It differs from
the latter in the ramification of the radial main-spines, wherein it agrees with the
former. Castanura may therefore be derived either from Castanissa by ramification
of the main-spines, or from Castanopsis by development of teeth around the mouth.

1 Castanwra = Chestnut with tails ; KOWTOWOH, oi>j«.

REPORT ON THE RADIOLARIA. 1689

1. Castanura tizardi, n. sp. (PI. 113, fig. 4, 4a).

Pores regular, circular, without hexagonal frames, twice as broad as the bars. Bristles twice as
long as one pore. Eadial main-spines somewhat longer than the radius, straight, very stout, with
irregular lateral branches, which are partly confluent. Mouth with six strong conical teeth.

Dimensions. — Diameter of the shell 0-6, of the pores 0'03.

Habitat. — Tropical Atlantic, Station 346, surface.

2. Castanura havergali, n. sp.

Pores regular, circular, hexagonally framed, as broad as the bars. Bristles three times as long
as one pore. Radial main-spines as long as the shell-diameter, in the basal half simple, in the
distal half with irregular, not confluent, lateral branches. Mouth with ten to twelve irregular,
parallel, conical teeth of different sizes.

Dimensions. — Diameter of the shell 0'5, of the pores 0'045.

Habitat. — Indian Ocean, Madagascar (Eabbe), surface.

3. Castanura sivirei, n. sp.

Pores regular, circular, hexagonally framed, as broad as the bars. Bristles half as long as the
radius. Eadial main-spines straight, longer than the shell-diameter ; on the distal end with a few
irregular, confluent, lateral branches. Mouth with six larger and six alternate smaller, parallel,
conical teeth.

Dimensions. — Diameter of the shell 0'2S, of the pores 0'015.

Habitat. — North Pacific, Station 253, surface.

4. Castanura carpcnteri, n. sp.

Pores irregular, roundish, twice to four times as broad as the bars. Bristles about as long as the
largest pores. Eadial main-spines irregularly curved, longer than the shell-diameter, with inflated
and fenestrated conical base ; in the distal half irregularly branched, with simple, not confluent,
lateral branches. Mouth with six to nine irregular, strong, conical teeth.

Dimensions. — Diameter of the shell 0'3, of the pores 0'012 to 0-025.

Habitat. — South Atlantic, Station 331, depth 1715 fathoms.

Family LXXXI. CIKCOPORIDA, Haeckel, 1879 (Pis. 114-117).

Circoporida, Haeckel, 1879, Sitzungab. med.-nat. Gesellsch. Jena, Dec. 12, p. 5.

Definition. — PH^ODARIA with a spherical or polyhedral shell, exhibiting a
peculiar solid porcellanous structure, with, a stellate circle of radial pores around the
base of the hollow radial spines. Mouth usually with teeth. Surface of the shell

(ZCOL. CHALL. EXP. — PART XL. — 1886.) Rr 212

1690 THE VOYAGE OF H.M.S. CHALLENGER.

tabulate, panelled or dimpled. Central capsule excentric, placed in the aboral half of
the shell-cavity.

The family Circoporida comprises those PH^EODARIA in which the simple,
spherical, or polyhedral shell exhibits a peculiar porcellanous structure, possesses a
simple mouth, and is particularly distinguished by the constant character denoted by their
name, viz., by circles of pores surrounding the base of the radial spines. It agrees in
these striking peculiarities with the following family, the Tuscarorida, but differs from them
essentially by the spherical or polyhedral form of the shell, which is never ovate, with the
main axis prolonged. The radial spines, variable in number, are regularly or symmetrically
disposed in all Circoporida, whilst they are arranged around the poles of the. main axis
in all Tuscarorida. Whilst the latter are always extremely large, more than a
millimeter in size, the former are much smaller and never reach the diameter of a
millimeter. The number of genera and species in this family is not large, and the
majority are very rare, but they belong to the most remarkable Badiolaria by the
peculiar structure, as well as by the geometrical regularity of the polyhedral shell.

The Circoporida may be divided into two different subfamilies, the Circogonida
and the Haeckelinida. The latter are represented by the single genus Haeckeliana
(PI. 114), and possess a spherical shell with numerous small dimples between the
circles of pores, and numerous simple radial spines which do not exhibit a regular ar-
rangement. The Circogonida, on the other hand, comprise all other genera (Pis.
115-117), and possess a panelled shell with polygonal plates, and a certain number
of radial spines, which are regularly disposed on the corners of the polyhedral shell,
and usually armed with verticillate bristles and terminal forks or spathillse. Perhaps
the Circogonida and Haeckelinida may better be considered as two separate families.

The geometrical fundamental form of the shell is in the Circoporida of the highest
interest, since it exhibits regular proportions, which are very rare in other organic
forms, generally some rare forms of regular polyhedrons. The shell in all members of
this family belongs to that group of geometrical forms which I have called in my
General Morphology " Polyaxonia " (vol. i., 1866, pp. 406-416). The shell therefore
is constantly an " endospherical polyhedron," i.e., a polyhedron, all the corners of which
lie in a spherical surface. The corners are always indicated by the bases of the radial
spines arising from the surface of the shell arid marking its axes, and it is immaterial
whether the shell itself is a true polyhedron or a sphere ; for in the latter case also the
radial spines mark the axes of the polyhedron.

The six genera, which we here distinguish among the Circoporida, represent six
different fundamental forms. Circoporus (PI. 115, figs. 1-3; PI. 117, figs. 5, 6)
possesses six radial spines, opposite in pairs in three diameters, perpendicular one to
another; it agrees therefore with the Cubosphaerida (p. 169, Pis. 21-25) and repre-

REPORT ON THE RADIOLARJA. 1691

scnts the regular octahedron, with eight congruent triangular faces and six corners.
It has the same form as the well-known antheridia of Chara (Gener. Morphol.,
vol. i. p. 412). Circogonia (PL 115, figs. 8-10; PL 117, fig. 1) exhibits twelve
radial- spines, opposite in pairs in six equidistant diameters. The surface of the shell
is divided into twenty equal and equilateral triangles, and agrees therefore with the
regular icosahedron. The same form appears also in some forms of Aulosphcera, and
in several Astrosphserida (Gener. Morphol., vol. i. p. 41 1). Circorrhegma (PL 117,
fig. 2) possesses a regular shell with twelve equal pentagonal faces and twenty
equidistant corners, from which arise twenty regularly disposed radial spines. It
represents therefore the regular " pentagonal dodecahedron," the same remarkable form
which is found in some Astrosphserida, and in the pollen -grains of some plants, e.g.,
Bucholzia maritima, Fumaria spicata, Polygonum amphibium, &c. (Gener. Morphol.,
vol. i. p. 412, Taf. ii. fig. 18 .

The three genera of Circoporida mentioned therefore represent three different forms
of regular polyhedrons, in the exact mathematical sense, viz., Circoporus, the regular
octahedron, Circogonia, the regular icosahedron, and Circorrhegma, the regular dodeca-
hedron. In each of these three regular forms all the faces, edges, and corners are
equal. The remaining three genera of Circoporida represent, however, three forms of
subregular or irregular endospherical polyhedra, which are not perfectly regular.
Circospathis (PL 115, figs. 4-7; PL 117, fig. 3) is a rather common form, and
constantly possesses nine symmetrically disposed radial spines ; the shell is either
spherical or polyhedral, with fourteen triangular faces and thirty edges ; the nine spines
lie in three meridional planes, which are crossed at equal angles (three equidistant spines
in each plane). We call this remarkable form the tetradecahedron ; it appears also in
some Astrosphserida (e.g., in Haliomma echinaster, figured in my Monograph, Taf.
xxiv. fig. 1). Circostephanus (PL 116, fig. 3) exhibits a subregular polyhedral shell
with a variable number of triangular faces and of radial spines (twenty-four to forty or
more). Circostephanus sexagenarius possesses sixty triangular equilateral faces, which
are disposed in twelve pentagonal groups (each with five faces), so that the shell seems
to be derived from a regular pentagonal dodecahedron, the twelve regular faces of
which are divided each into five congruent triangles. From its corners arise thirty -two
radial spines (twelve from the central points of the pentagons, twenty from the meeting
corners of every three pentagons). In other cases the number of faces and radial spines
seems to be larger and their arrangement more irregular. The same may be said of
Haeckeliana, in which the dimpled shell is constantly spherical, and possesses a variable
number of radial spines, from sixteen to fifty -five (usually between thirty and forty).

The structure of the shell in the Circoporida is the same as in the Tuscarorida, of
a peculiar porcellanous nature. The shell-wall is very thick, more or less opaque,, and in
direct light whitish or yellowish. Its surface is dimpled, with numerous small, circular,

1692 THE VOYAGE OF H.M.S. CHALLENGER.

roundish or polygonal dimples in Haeckeliana (PI. 1 14, figs. 1-6). In the Circo-
gonida, however, the surface is panelled, with regular or irregular polygonal plates,
often separated by high prominent crests (PI. 115, figs. 4-9, &c.). Numerous simple
thin needles of silica lie tangentially disposed and irregularly scattered in the por-
cellanous or cement-like substance of the thick shell-wall. Under a strong lens
this substance appears finely punctate, being probably pierced by numerous very fine
pores. The surface of the shell is therefore minutely roughened, and often appears quite
black under the microscope, by the adhesion of innumerable fine air-bubbles. In all
Circoporida, as well as in the Tuscarorida, the porcellanous shell has not the perfect
transparency of the purely siliceous shells of other Radiolaria ; its refractive power is
somewhat different from the latter ; it becomes deeply stained by carmine and browned
by fire, and seems therefore to consist of a peculiar carbonic silicate.

The shell in all Circoporida exhibits a simple, excentric mouth, which corresponds
to the main osculum of the central capsule. The excentric position of this shell-mouth
has no influence on the regular form of the shell. The mouth is either circular or
polygonal, usually about as large as a basal circle of pores. It is always armed with
prominent conical or pyramidal teeth, the number of which is variable and seems to
depend partly upon the number of the shell-faces or the radial spines. Circoporus
has usually four cruciate teeth (PL 115, fig. 1 ; PI. 117, figs. 4, 5). Circorrhegma
exhibits a pentagonal mouth with five teeth (PI. 117, fig. 2). Circogonia possesses
a hexagonal mouth with six teeth (PI. 115, fig. 8; PI. 117, fig. 1). Circospathis
has no constant number ; some species have five teeth (PI. 115, fig. 4), others four
(PI. 115, fig. 10), others nine (PI. 117, fig. 3a). Circostephanus is also variable;
one species exhibits eight teeth (PL 116, fig. 3a), another ten, another twelve. In
Haeckeliana (PL 114, fig. 3) the teeth are smaller and more numerous. Usually the
teeth arise vertically from the surface of the shell and are spinulate ; more rarely their
points are directed towards the centre of the mouth. Sometimes numerous thin needles
arise between the teeth (PL 115, fig. 10).

The radial spines of the Circoporida are tubular, usually cylindrical and conical
at the thickened base, more rarely prismatic or slenderly pyramidal, with three or more
edges; sometimes the edges are' spirally wound around the axis (PL 115, fig. 6).
In the majority of species their length is about equal to the diameter of the shell ;
often they are somewhat shorter, more rarely longer. Their tubular structure is always
the same as in the Tuscarorida ; the wall of the tube is thick, and in the axis of its cavity
lies an axial cord or funicle, which is connected with the wall by numerous horizontal,
simple, or branched threads (PL 115, figs. 6, 7). The axial funicle itself is either a
simple thread of silica, or a strand, composed of three to fifteen or more filaments, which
are closely twisted like a rope around the axis of the spine, and arise separately from
the bridges between the pores of the basal circle (PL 115, figs. 7, 9). The number of

REPORT ON THE RADIOLARIA. 1693

pores in these circles is very variable, commonly from three to nine, sometimes twelve
to fifteen or more ; their form is usually irregularly ovate (PI. 115, figs. 7, 9). The
bridges between the pores usually bear numerous siliceous threads or bristles, which are
curved downwards or upwards (PI. 115, figs. 4—6). Sometimes the spines are entirely
covered with similar bristles or cilia (PL 117, figs. 2—5), more rarely with regular
verticils of lateral branches (PI. 117, fig. 6).

The distal ends of the radial spines are simple in Haeckeliana (PI. 1 14), whilst in
the other Circoporida they are usually (or perhaps constantly) either forked or armed
with a verticil of terminal branches. When the spines are simply forked, their two
terminal branches lie in certain meridional planes (PI. 117, fig. 5). The same is
probably the case when they bear three divergent branches (PI. 115, figs. 1, 2),
or four crossed branches (PI. 117, figs. 4, 6). The larger species usually bear a
corona of five curved branches disposed around the distal apex of each spine (PI. 116,
fig. 3; PI. 117, figs. 1, 2). Sometimes the formation of these coronas is twice or
more often repeated, so that the spines appear verticillate.

The central ca%>sule of the Circoporida (PI. 115, fig. 8; PI. 117, fig. 6) is usually
about half as large as the enclosing shell, and lies excentrically in that half of its cavity
which is remote from the shell-mouth (PI. 115, fig. 8). The other half (near the
mouth) is filled up by the cap-shaped, dark phgeodium. The proboscis, or the central
tubule of the astropyle, is hidden in the axis of the blackish phseodium, and is directed
towards the mouth of the shell ; it is often S-shaped, more or less curved. The circular
radiate operculum of the astropyle, placed on the base of the proboscis, exhibits
numerous branched radial ribs, and closes the main-opening like the lid of a tea-kettle
(PI. 115, fig. 3). The number of the parapylse, or the accessory openings of the
capsule, which in the majority of PH^ODARIA is two, seems to be usually increased in
the Circoporida. In Circoporus the capsule seems to possess six and in Circospathis nine
secondary openings, and therefore there is some probability that each circle of pores on
the base of a radial spine corresponds to a secondary opening of the capsule. In
Haeckeliana, however (PI. 114), I could observe no parapylse at all. These accessory
openings are always very small in the Circoporida, and may be easily overlooked.
Futhermore, the number of observations respecting this difficult point is too small,
and their certainty not satisfactory; it requires therefore further accurate examination,
as also does the whole central capsule of the Circoporida.

The numerous and remarkable characters of shape and structure, which we have
described above as occurring in the Circoporida, are also found in the following closely
allied family, the Tuscarorida ; all the species are inhabitants of great depths. Perhaps
it may therefore be more convenient to separate these two families from the other
PH.EOGROMIA as a peculiar order, under the name PH.EOCALPIA.

1694 THE VOYAGE OF H.M.S. CHALLENGER.

I. Subfamily

Circogonida.
Shell spherical or poly-

Synopsis of the Genera of Circoporida.

Shell octahedral (or spherical), Six radial spines, . . 711. Gireoporus.

Shell tetradecahedral, . Nine radial spines, . .712. Circospathis.

hedralwith panelled

structure and poly- j Shell icosahedral, . . Twelve radial spines, . 713. Circogonia.

gonal plates. A

certain number of
radial spines are
geometrically dis-
posed.

Shell dodecahedral, . . Twenty radial spines, . 714. Circmrherfma.

Shell polyhedral, . . Twenty-four to forty or more

radial spines, . .715. Circosteplxmus.

II. Subfamily ( Shell spherical, with dimpled structure, and a variable number

Haeckelinida. \ of radial spines (without polygonal plates), . .716. Haeckeliana.

Subfamily 1. CIRCOGONIDA, Haeckel.

Definition. — C ircoporida with panelled shell, composed of polygonal plates.
The shell is usually polyhedral, more rarely spherical, and the radial spines are usually
(or perhaps constantly) branched and regularly arranged.

Genus 711. Circoporus,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C ircoporida with a spherical or regularly octahedral shell, com-
posed of eight congruent, triangular plates, with six corners from which arise six
radial spines, opposite in pairs in three diameters, perpendicular one to another.

The genus Circoponis, the simplest among the Circoporida, is distinguished by the
regular octahedral form of the shell, with the three equal axes of the regular crystalline
system perpendicular one to another. Six equal radial spines, arising from the six
corners, lie opposite in pairs in those three dimensive axes. The eight equal
triangular faces of the octahedron are sometimes plane, sometimes concave or convex,
and sometimes the shell becomes spherical. In this case it becomes very similar to the
Hexastylida among the Sphseroidea.

1. Circoporus sexfurcus. Haeckel (PL 117, fig. 5).

Cliallengeria sp., John Murray, 1876, Proc. Eoy. Soc. Lond., vol. xxiv. pi. xxiv. fig. 5.

Shell spherical, covered with irregular, polygonal plates. Six radial spines shorter than the
diameter of the shell, covered with thin curved bristles, in the proximal half cylindrical, in the
distal half forked, each with two equal curved fork-branches. Around the ciliated base of each spine a

1 Circoporus = Shell with circles of pores ; XI'^KO

REPORT ON THE RADIOLARIA. 1695

corona of twelve to sixteen pores surrounded by a circle of numerous, curved, longer bristles.
Mouth cruciform, with four triangular, convergent teeth.

Dimensions. — Diameter of the shell 0'55, length of the spines 0'4.

HaUtat. — South Pacific, Station 289, depth 2550 fathoms.

2. Circoporus hexastylus, n. sp. (PL 117, fig. 4).

Shell regularly octahedral, with eight plane, congruent, triangular faces, which are covered
with a very delicate network of small, regular, hexagonal plates. Six radial spines as long as the
radius of the shell, four-sided pyramidal, simple, in the basal half covered with numerous curved
bristles. Around the base of each spine a corona of four equal pores, surrounded by a circle of
twelve short teeth. Apex with four crossed, curved branches (like those of Circospathis tetrodon).
Mouth cruciform, with four smooth teeth.

Dimensions. — Diameter of the shell 0'24, length of the spines 0'12.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Circoporus characeus, n. sp.

Shell spherical, covered with a delicate network of irregular polygonal plates. Six radial spines
longer than the diameter of the shell, cylindrical, covered with numerous curved bristles, each with
eight pores at the base surrounded by a circle of long bristles. Apex of each spine with a trident
or fuscina, similar to that of the following species. Similar to an antheridium of Chara.

Dimensions. — Diameter of the shell 0'32, length of the spines 0'4.

Habitat. — South Pacific, Station 285, depth 2375 fathoms.

4. Circoporus sexfuscinus, n. sp. (PL 115, figs. 1-3).

Shell subregular, octahedral, with eight triangular, concave, somewhat unequal faces, which are
covered with an extremely delicate network of small square dimples, and furrowed by radial crests
arising from the bases of the spines (fig. 2). Six radial spines about as long as the diameter of the
shell, four-sided, prismatic, with rounded edges ; each in the basal, half with a verticil of four crossed,
curved bristles (fig. 1), sometimes with two verticils (fig. 2) ; on the distal apex inflated, armed
with a trident or fuscina. Around the base of each spine four crossed elliptical pores. Mouth
cruciform, with four small teeth (fig. 1).

Dimensions. — Diameter of the shell 02 to O25, length of the spines 0'2 to 0'2o.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

5. Circoporus octahedrus, n. sp. (PI. 117, fig. 6).

Shell regularlyoctahedral, with eight plane, or slightly convex, congruent, triangular faces, which
are covered with very small, regular, triangular plates (like those of Polypetta tabulata, PI. 116,
fig. 2). Six stout radial spines, about as long as the diameter of the shell, four-sided prismatic,

1696 THE VOYAGE OF H.M.S. CHALLENGER.

covered with three or four verticils of four long curved bristles; at the distal apex inflated, with
four crossed, divergent, stout, curved horns. Around the pyramidal base of each spine a corona of
eight pores (two on each of the four faces). Mouth cruciform, with four triangular, convergent teeth.

Dimensions. — Diameter of the shell 016, length of the spines 018.

Habitat.— South Pacific, Station 298, depth 2225 fathoms.

Genus 712. Circospathis,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C ircoporida with a subregular, spherical, or polyhedral shell,
composed of fourteen triangular, nearly equal plates, with nine corners, from which
arise nine radial spines, symmetrically disposed.

The genus Circospathis exhibits the remarkable and peculiar form of a "Tetra-
decahedron," or a subregular polyhedron with fourteen triangular faces, thirty edges, and
nine corners, from which arise nine radial spines. These lie in three meridional planes,
which are crossed at equal angles (three equidistant spines in each plane). The same
interesting form occurs also in some Astrosphaerida, which bear nine regularly disposed
radial spines, as Haliomma echinaster. All four observed species of Circospathia are
South Atlantic.

1. Circospathis furcata, n. sp. (PI. 115, figs. 4-G).

Shell polyhedral or nearly spherical, with nine prominent corners, from which arise nine radial
spines, about as long as the diameter of the shell. The polygonal plates of the shell are separated
by high crests, usually hexagonal or pentagonal, irregular, about twelve to fifteen on the half
meridian. Eadial spines cylindrical, straight, about as long as . the diameter of the shell, with
spirally turned edges, covered with numerous curved bristles, at the distal end forked ; the two
fork branches curved, one-third as long as the simple basal part. The inflated base of each spine is
surrounded by a corona of nine to twelve ovate basal pores. Mouth pentagonal, with five thick,
mammillate and spinulate, somewhat convergent teeth (fig. 5).

Dimensions. — Diameter of the shell 0'6, length of the spines 0'5.

Habitat. — South Atlantic (east of Buenos Ayres), Station 325, depth 2650 fathoms.

2. Circospathis novena, n. sp. (PI. 117, figs. 3, 3a).

Shell polyhedral (tetradecahedral), with fourteen triangular, plane, or slightly convex faces, covered

with small, irregular, polygonal (usually hexagonal) plates, and nine prominent corners, from which

arise nine radial spines, shorter than the diameter of the shell. Each spine is surrounded at the

broader base by a circle of twelve to sixteen pores and a corona of bristles, and bears at the

1 Circospathis = Shell with verticils around the spines ;

REPORT ON THE RADIOLARIA. 1697

inflated distal apex a trident or fuscina, similar to that of Circoporus sexfuscinus (PI. 115, fig. 2).
Mouth with nine convergent, conical, denticulate teeth (fig. 3a).

Dimensions. — Diameter of the shell 0'6, length of the spines 0'4.

Habitat. — South Atlantic, Station 318 (east of Patagonia), depth 2040 fathoms.

3. Circospathis tetradeca, n. sp.

Shell spherical, covered with irregular, polygonal plates. Nine radial spines, cylindrical, as long
as the radius of the shell, bristly, armed at the distal apex with a trident. (In one specimen six
spines possessed three terminal branches, two spines two branches, and one spine four branches.)
The broader base of each spine is surrounded by a corona of nine pores and a circle of curved
bristles. Mouth with nine smooth conical teeth.

Dimensions. — Diameter of the shell 0'55, length of the spines 0'3.

Habitat. — South Atlantic, Station 332 (west of Tristan da Cunha), depth 2200 fathoms.

4. Circospathis tetrodonta, n. sp. (PI. 115, fig. 10).

Shell subspherical or polyhedral, with fourteen triangular, convex faces, covered with irregular
polygonal plates. Nine radial spines cylindrical, nearly smooth, about as long as the diameter of
the shell ; at the distal apex with four strong curved horns, like those of Circoporus hexastylus,
PI. 117, fig. 4. Each spine is surrounded at the base by a corona of nine irregular pores. Mouth
with four large, prominent, conical teeth, which are spinulate, with vertical inner edge (fig. 10).

Dimensions. — Diameter of the shell 0'5, length of the spines 045.

Habitat. — South Atlantic, Station 323 (east of Buenos Ayres), depth 1900 fathoms.

Genus 713. Circogonia,1 n. gen.

Definition. — C ircoporida with a regular icosahedral shell, composed of twenty
congruent, triangular plates, with twelve corners,, from which arise twelve radial spines.

The genus Circogonia is remarkable for the regular icosahedral form of its shell, a
geometrical fundamental form, which occurs very rarely in organised bodies (as in
AulacantJia icosahedra, and in some Astrosphserida with twelve regularly disposed
radial spines). The shell is composed of twenty triangular, equilateral and congruent
plates, which are sometimes separated by prominent crests ; their surface is panelled by
smaller hexagonal or polygonal secondary plates. The thirty edges between the plates
are sometimes thickened. From the twelve corners of the regular icosahedron (where
every five triangular plates meet), twelve equal radial spines arise, each of which is
surrounded at the base by a corona of nine to sixteen pores. Two species only of
Circogonia have been observed; the one has smooth spines, forked at the distal end,

1 Circogonia = Polyhedron with circles of pores ; */{*of, yui/t'ct.
(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 213

1698 THE VOYAGE OF H.M.S. CHALLENGES.

the other bears numerous curved bristles around each spine, and at the distal end a
verticil of five curved branches. The mouth of the shell (placed in the centre of one of
the triangular plates) is in both species armed with six teeth. Both species are found
in the Tropical Atlantic.

1. Circogonia icosahedra, n. sp. (PL 117, figs. 1, la).

Shell regularly icosakedral, with twenty equal, triangular, nearly plane faces, which are separated
by thirty prominent, crest-like edges, and covered by a delicate network of small, subregular, hexagonal
plates. Twelve radial spines nearly conical, one and a half times as long as the radius of the shell,
with five prominent edges. The campanulate base of each spine is covered with numerous long,
curved bristles, surrounded by a circle of twelve to sixteen ovate, irregular pores, and separated from
the slender distal part by a constriction. The distal apex of the spine is surrounded by a verticil
of five conical, curved branches (corresponding to the five edges of the spines, and to the five faces,
which meet in the corners where the spine arises). Mouth hexagonal, with six conical, spinulate
teeth, convergent towards its centre (fig. la).

Dimensions. — Diameter of the shell 0-75, length of the spines 0'5.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

2. Circogonia dodecacantha, n. sp. (PL 115, figs. 8, 9).

Shell subregularly icosahedral, with twenty equal, triangular, slightly convex faces, which are
not separated by prominent crests, but covered with a network of irregular polygonal plates.
Twelve radial spines, cylindrical, smooth, about as long as the diameter of the shell, forked at the
distal end, with two divergent, slightly curved branches (similar to Circospatliis furcata, PI. 115,
figs. 4—6). The conical base of each spine is surrounded by a circle of nine to twelve irregular,
ovate pores (fig. 9). Mouth circular, with a corona of six conical, smooth teeth which arise per-
pendicularly from the shell (in the upper part of fig. 8, at left).

Dimensions. — Diameter of the shell 0'6, length of the spines 0-I7.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

Genus 714. Circorrhegma,1 n. gen.

Definition. — C ircoporida with a regular dodecahedral shell, composed of twelve
congruent, pentagonal plates, with twenty corners, from which arise twenty radial
spines.

The genus Circorrhegma is remarkable for the geometrical regularity of its shell,
which represents a pentagonal dodecahedron. The shell is therefore composed of twelve
equal and regular pentagonal plates, and these are separated" in the only known

1 Circorrhegma = Shell with circles of fissures ; x/jxoj,

REPORT ON THE RADIOLARIA. 1699

species by thirty prominent crest-like edges. From the corners of the dodecahedron,
at which every three pentagons meet, arise twenty radial spines, opposite in pairs in ten
equidistant axes.

1. Circorrhegma dodecahedra, n. sp. (PI. 117, figs. 2, 2a).

Shell dodecahedral, with twelve equal and regular, plane, pentagonal plates, which are separated
by thirty prominent crests, and bear a network of numerous polygonal (usually also pentagonal),
smaller plates. Twenty radial spines about as long as the radius of the shell, three-sided prismatic,
covered with numerous bristles; each surrounded at the thickened base by a circle of twelve to sixteen
pores, and at the distal apex by a corona of five curved, terminal branches. Mouth pentagonal, with
five conical, subvertical, spinulate teeth (fig, 2a).

Dimensions, — Diameter of the shell 0'8, length of the spines 0'5.

Habitat. — Indian Ocean, Madagascar (Rabbe).

Genus 715. Circostephanus,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 5.

Definition. — C ircoporida with a subregular, polyhedral or nearly spherical
shell, composed of thirty to sixty or more triangular plates, with twenty-four to thirty-
two or more corners, from which arise radial spines, symmetrically disposed.

The genus Circostephanus comprises those Circoporida in which the porcellanous
shell is an endospherical polyhedron, with numerous (thirty to sixty or more) triangular
faces, and has a variable number of radial spines (twenty -four to forty or more), arising
from its corners. The number of faces and corners seems to be variable in this genus,
but may perhaps be typical in some species. Circostephanus sexagenarius has the
typical form of a " Sexagenal-Polyhedron," with sixty equal triangular faces and thirty-
two corners, and may be derived from the " Pentagonal-Dodecahedron " (Circorrhegma)
by dividing its twelve pentagonal faces each into five congruent triangles.

1. Circostephanus coronarius, n. sp. (PI. 116, figs. 3, 3a, 36).

Shell polyhedral, with thirty- two to forty triangular, concave faces of nearly equal size, which
are separated by high prominent crests. From the elevated corners of the polyhedron arise twenty-
four to thirty radial spines, which are three- sided prismatic or nearly cylindrical, about as long as
the radius of the shell, and covered with long curved bristles. The distal end of each spine is
surrounded by a verticil of five stout, curved branches, its pyramidal base by a corona of five (or
1 Circostephanus= Shell with circular coronets;

1700 THE VOYAGE OF H.M.S. CHALLENGER.

sometimes six) ovate, basal pores (fig. 3&). Mouth armed with a corona of eight short, conical,
vertical, spinulate teeth (fig. 3a).

Dimensions. — Diameter of the shell 0'4 to 0'5, length of the spines 0'2 to 0'25.

Habitat. — South-Eastern Pacific (off Valparaiso), Station 298, depth 2225 fathoms.

2. Circostephanus sexagenarius, n. sp.

Shell polyhedral, with sixty triangular, equilateral, congruent faces, which are nearly plane, and
separated by high prominent crests. They are disposed in twelve pentagonal groups, each with five
faces, so that they appear as if derived from a regular pentagonal dodecahedron, the twelve regular
faces of which are each divided into five congruent triangles, meeting in its centre. From the
elevated corners of the polyhedron arise thirty-two radial spines (twelve in the central points of
the pentagons, twenty in the meeting corners of every three pentagons). The. radial spines are
nearly as long as the diameter of the shell, cylindrical, spinulate, and surrounded at the distal -end
by a verticil of five stout, curved branches, and at the pyramidal base by a corona of twelve to sixteen
basal pores. Mouth armed with a corona of twelve conical, vertical, spinulate teeth.

Dimensions. — Diameter of the shell 0'75, length of the spines 0'6.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

3. Circostephanus polygonarius, n. sp.

Shell polyhedral, with sixty to eighty subregular, triangular, concave faces, which are separated
by prominent crests. From the elevated corners of the polyhedron arise thirty to forty radial
spines, which are longer than the diameter of the shell, densely covered with curved bristles and
three-sided prismatic, with three spirally convoluted edges. Their distal end is surrounded by a
verticil of eight or nine curved branches, and their pyramidal base by a corona of eight or nine basal
pores. Mouth armed with a corona of ten conical, vertical, spinulate teeth.

Dimensions. — Diameter of the shell 0'8, length of the spines 0'9.

Habitat. — South Pacific, Station 288, depth 2600 fathoms.

Subfamily 2. HAECKELINIDA.

Definition. — C ircoporida with dimpled spherical shell, not composed of polygonal
plates. The shell is covered with small roundish dimples, never polyhedral, and the
radial spines are simple, not branched, and usually not regularly arranged.

Genus 716. Haeckeliana, John Murray, 1879, in schedulis, Chall. Coll.

Definition. — C irco'porida with spherical shell of a peculiar dimpled, porcellanous
structure, and with a variable number of simple radial main-spines which are usually
not regularly arranged.

REPORT ON THE RADIOLARIA. 1701

The genus Haeckeliana comprises the spherical Circoporida, with dimpled, porcellanous
shell, which are widely distributed, but rather rare, in depths between 2000 and 3000
fathoms. All the known species (six in number) are very closely related, and though
the extreme forms appear very different in size and structure, they are so connected by
a continuous series of intermediate forms, that they may be regarded as varieties of a
single species, first observed by Dr. John Murray, and called by him Haeckeliana
porcellana. The number of radial spines may be from sixteen to fifty-five, and is
usually between thirty and forty. Each is surrounded by a basal coronet of aspinal
pores, usually five, more rarely four or six; the number, however, is not constant in any
one species. Each coronet is armed with an outer ring of by -spines. The surface of
the shell between the coronets is dimpled. The mouth (PI. 114, fig. 3) is about as large
as a corona, and also armed with a ring of by-spines. The structure of the thick
porcellanous shell and the radial spines is different from the other Circoporida.

/

1. Haeckeliana porcellana, John Murray (PI. 114, fig. 6).

Haeckeliana porcellana, John Murray, 1879, in schedules, Chall. Coll.

Shell with forty to forty-five coronets, the majority of which have five pores (more rarely four or
six). Coronets broader than their intervals, and twice as broad as the length of the by-spines.
Dimples subcircular, of the same breadth as the pores. Main-spines about as long as the radius.

Dimensions. — Diameter of the shell 0'37 to 0'42, of the coronets 0-06 to 0'07.

Habitat. — South Pacific, Stations 289 to 293, depth 2025 to 2550 fathoms.

2. Haeckeliana maxima, n. sp. (PI. 114, fig. 5).

Shell with fifty to fifty-five coronets, the majority of which have six pores (more rarely five or
seven). Coronets broader than their intervals, and eight to ten times as broad as the length of the
by-spines. Dimples irregularly polygonal, of about the same breadth as the pores. Eadial main-
spines about as long as the diameter of the shell.

Dimensions. — Diameter of the shell 0'5 to 0'52, of the coronets 0'08 to 0'09.

Habitat. — Equatorial Atlantic, Station 347. depth 2250 fathoms.

3. Haeckeliana lamarckiana, n. sp. (PI. 114, fig. 4).

Shell with thirty-five to forty coronets, the majority of which have five pores (more rarely six or
four). Coronets broader than their intervals ; each funnel-shaped pore on the inside with a circle
of small conical thorns. By-spines rudimentary or wanting. Dimples irregularly polygonal, half
as broad as the pores. Eadial main-spines shorter than the radius.

Dimensions. — Diameter of the shell 0'38 to 045, of the coronets 0'06 to 0'07.

Habitat. — South Atlantic, Stations 318 to 333, depth 2000 to 2900 fathoms.

1702 THE VOYAGE OF H.M.S. CHALLENGER.

4. Haeckeliana murrayana, Haeckel.

Challengeria sp., John Murray, 1876, Proc. Roy. Soc,, vol. xxiv. pi. xxiv. fig. 6.

Shell with twenty to twenty-five coronets, the majority of which have five pores (more rarely
four or six). Coronets of about the same breadth as their intervals, and twice as broad as the
by-spines. Dimples subcircular, of about the same breadth as the pores. Eadial main-spines about
as long as the radius.

Dimensions. — Diameter of the shell 0-35 to 0-4, of the coronets 0-06 to 0'07,
Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

5. Haeckeliana goetheana, n. sp. (PI. 114, fig. 3).

Shell with sixteen to twenty coronets, the majority of which have four pores (more rarely five
and very rarely six). Coronets smaller than their intervals. By-spines very short or rudimentary.
Dimples subcircular, half as broad as the pores. Eadial main-spines shorter than the radius.

Dimensions. — Diameter of the shell 0'25 to 0-3, of the coronets 0'04 to 0'05.

Habitat. — North Pacific (south of Japan), Station 231, depth 2250 fathoms.

6. Haeckeliana darwiniana, n. sp. (PI. 114, figs. 1, 2).

Shell with twenty-six to thirty-two coronets, the majority of which have five pores (rarely four
or six). Coronets smaller than their intervals and than the length of the by-spines. Dimples
subcircular, half as broad as the pores. Eadial main-spines longer than the radius.

Dimensions. — Diameter of the shell 0'30 to 0'42, of the coronets 0'07 to 0'08.

Habitat. — North Pacific (east of Japan), Stations 241 to 245, depth 2300 to 2900 fathoms.

Family LXXXII. T u s c A R o R I D A, n. fam. (PI. 100).

Definition. — PH/EODARIA with an ovate, spindle-shaped, or nearly spherical shell
exhibiting a peculiar solid porcellanous structure; with a few radial pores around the base
of the hollow tubules, which are symmetrically arranged around the main axis and the
mouth. Surface of the shell smooth or spiny, not tabulate nor panelled. Central
capsule excentric, placed in the aboral half of the shell-cavity.

The Tuscarorida, and the preceding closely allied family, the Circoporida,
represent together a peculiar small group, which differs from the other PH^ODAKIA in
the singular porcellanous structure of the shell-wall, and may be called Phseocalpia;
their hollow radial spines are distinguished by peculiar basal pores, forming a circle
around their base. The shell of the Tuscarorida is monaxonian, ovate, spindle-shaped

REPORT ON THE RADIOLARIA. 1703

or nearly spherical, whilst in the Circoporida it is polyaxonian, spherical or polyhedral ;
the hollow radial spines are arranged in the former around the main axis, in the latter
around the common central point. All Phseocalpia (the Tuscarorida as well as the
Circoporida) are inhabitants of great depths, usually between 2000 and 3000 fathoms.

Though the number of Tuscarorida at present known is small (only three genera,
with ten species), they represent a very distinct and remarkable family of PH^EODARIA,
as well by their considerable size, as by the peculiar arrangement of the radial spines
and the structure of the shell-wall, which in some species is more solid and thicker than
in any other Eadiolaria. The diameter of the shell is always more than 1 mm., usually
between 1 and 2, and sometimes more than 3 mm.

The dry shell of the Tuscarorida is not hyaline and transparent as is usual in the
other Kadiolaria, but perfectly opaque, milk-white or yellowish -white. This opacity is
caused by innumerable very fine pores, which everywhere pierce the thick, apparently
solid, fundamental substance of the shell-wall. Besides those very small pores, it is
also pierced by a certain number of larger pores, which are scattered at wide distances
(Narr. Chall. Exp., vol. i. pi. A, fig. 15&). These larger pores or pore-channels have a
diameter of about O'Ol mm., and pierce the shell -wall either in a perpendicular or in
an oblique direction. Very numerous straight, simple, and thin needles, usually O'l to
0'2 mm. in length, similar to the thin tangential needles of the Aulacanthida, are every-
where scattered tangentially in the cement-like fundamental substance, which seems to
be a peculiar carbonic silicate ; their axis is parallel to the shell-surface.

The general form of the shell is somewhat different in the three genera of
Tuscarorida; ovate or spherical in Tuscarora and Tuscarusa, which bear no caudal axial
spine (PL 100, figs. 1—7), or sometimes three-sided pyramidal (fig. 4) ; it is spindle-
shaped in Tuscaridium, which bears on the aboral pore an axial caudal spine (PL 100,
fig. 8). In every case the main axis of the shell, determining its monaxonian funda-
mental form, is indicated by the mouth, which is placed in the oral pole of the main
axis and prolonged into a short tube or proboscis.

The hollow apophyses, arising from the shell of the Tuscarorida, are always
cylindrical, long and thin tubules, the narrow cavity of which communicates directly
with the large shell-cavity. In the axis of the tubules lies a thin axial chord or funicle,
composed of a few (usually three or four) siliceous threads which arise from bridges
between the basal pores of the apophyses, and are twisted together like the strands of
a rope. The axial funicle is connected with the thin wall of the tubular apophyses by
innumerable very thin radial beams, perpendicular to the axis (PL 100, fig. 3a, 5&).
The surface of the apophyses is almost constantly covered with numerous small bristles
or spines, which are usually curved and directed towards their distal ends.

Tuscarora (PL 10O, figs. 1-6) exhibits two different groups of apophyses, which
may be distinguished according to their different position and direction as " circoral

1704

THE VOYAGE OF H.M.S. CHALLENGER.

teeth" and " aboral feet"; the teeth immediately surround the opening of the mouth,
whilst the feet are remote from it and usually placed in the aboral half of the body,
more rarely in the equator or in the oral half. The general form and structure are the
same in both groups of apophyses, but their position and direction is different ; the
circoral teeth are directed forwards, often parallel (at the base at least), while the aboral
feet are either divergent and directed backwards, or they diverge forwards in the basal
part, then form a large arch, and finally curve backwards.

The number of the aboral feet, and their position relative to the circoral teeth, are
different but probably constant in each single species, and serve, in the first place, for the
distinction of genera and species. Tuscarora (in restricted sense) (PI. 100, figs. 1—6),
has constantly three feet (comparable to the three cortinar feet of the tripodal
NASSELLARIA) ; Tuscarusa (PI. 100, fig. 7) has four feet, opposite in pairs and
forming a regular cross; Tuscaridium, finally (PI. 100, fig. 8), has only one foot,
which is situated in the main axis, on its aboral pole, and may therefore be called a
caudal spine.

The number of the circoral teeth varies from two to four, and is usually three.
Originally these three teeth alternate regularly with the three aboral feet, so that the
latter may be regarded as perradial, the former as interradial (PI. 100, figs. 1—4). The
proportion of the number of each group of apophyses in the different species is synopti-
cally shown in the following table : —

Depth
in

Fathoms.

Challenger
Station.

Length
of the
Shell.

Breadth
of the

Shell.

Number
of Feet.

Number
of Pedal
Pores.

Number
of Teeth.

Number
of Dental
Pores.

1. Tuscarora bisternaria,

3000

264

2-0

1-5

3

8

3

8

2. murrayi,

2000

295

2-5

1-5

3

3

3

3

8. wyvillei,

2250

291

1-5

1-4

3

4

3

4

4. tetrahedra,

2450

348

2-5

2-0

3

4

3

3

5. tubulosa,

3000

249

1-4

1-2

3

4

2

3

6. porcellana,

2650

325

1-5

1-3

3

4

n

4

7. telknapii,

2025

293

2-5

1-5

3

3

4

2

8. Tuscarusa medusa,

3125

253

1-2

1-0

4

4

2

2

9. Tuscaridium cygneum,

3050

250

3-2

1-6

1

2

4

4

10. „ lithomithium,

3000

264

3-6

1-8

1

4

4

6

The base of the apophyses in all Tuscarorida is inflated, conical, and pierced by a
small number of large ovate pores, the typical " basal pores," which occur also in the
closely allied Circoporida. The number of these basal pores varies from two to eight,
and is usually three or four ; it never becomes in this family so great as in the
Circoporida, where each circle of pores is often composed of sixteen to twenty-four or
more basal pores. The number seems to be rather constant in each single species, as
may be seen in the preceding Table. The pedal pores (on the base of the aboral feet) are
usually larger than the dental pores (on the base of the circoral teeth). Their form is

REPORT ON THE RADIOLARIA. 1705

usually irregularly ovate or triangular ; their outer aperture is armed with spines or
bristles, which are commonly larger than in the other parts of the apophyses.

The mouth of the shell varies in form, according to the number and arrangement
of the teeth on its corners. It is therefore a narrow transverse fissure, with two broad
opposite lips and two corners, in the bidental forms (PL 100, figs. 5, 7), triangular in
the tridental species (figs. 1—4), quadrangular or square in the quadridental species,
Tuscarora belknapii (Narr. Chall. Exp., loc. cit., pi. A, fig. 15). The singular genus
Tuscaridium (fig. 8) exhibits four teeth, which are nearly horizontally divergent in
two pairs, a dorsal and a ventral pair (corresponding in position to the four feet of
Tuscarusa, fig. 7) ; the mouth is here prolonged into a cylindrical, spinulate proboscis,
which is curved towards the ventral face of the shell (fig. 8).

The central capsule of the Tuscarorida is kidney-shaped or spheroidal, scarcely half
as large as the dark olive-green phseodium, which surrounds its anterior (oral) face.
Usually the capsule and the phseodium together fill up the aboral half of the shell-
cavity, and are separated from its walls by the calymma. The latter is pierced by
numerous branched and reticulately anastomosing pseudopodia, which arise from the
matrix enveloping the capsule, and pass over into a thin layer of sarcode, adjacent to
the inner surface of the shell. The astropyle or the main-opening of the central
capsule exhibits the usual radiate operculum and tubular proboscis of. the PH^EODARIA
(PL 115, fig. 3), and is directed towards the mouth of the shell. The number of the
parapylse or accessory openings seems to be variable in this family, and to correspond
to the number of radial feet which arise from the shell. Therefore Tuscaridium
possesses only one parapyle, which is diametrically opposite to the mouth, lies on the
aboral pole of the capsule, and is directed towards the single caudal tube. Tuscarora
seems to have three parapylse, corresponding to the three radial feet, and Tuscarusa
probably has four parapylse, directed towards its four radial feet; in the latter genus,
however, the capsule was not observed (the shell being empty) ; and in the other
Tuscarorida this important and difficult anatomical question must be solved by further
accurate examinations.

The nucleus is nearly half as large as the central capsule, ellipsoidal, and contains
numerous nucleoli. In one specimen of Tuscarora belknapii I observed two nuclei
in the central capsule, and in another specimen of the same species John Murray
observed two central capsules (figured by him in the Narr. Chall. Exp., vol. i. pi. A,
fig. 15).

Synopsis of the Genera of Tuscarorida.

Three equidistant aboral radial feet, . . . . . .717. Tuscarora.

Four equidistant aboral radial feet, .... . . 718. Tuscarusa.

One single aboral foot or terminal spine, . . . . .719. Tuscaridium.

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 214

1706 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 717. Tuscarora,1 John Murray, 1876, in schedulis, Chall. Coll.

' Definition. — T uscarorida with three radial aboral feet, and a variable number
of circoral teeth.

The genus Tuscarora, comprises seven of the ten observed species of Tuscarorida,
all seven agreeing in the possession of three perradial feet, which alternate originally
(in four species), with three interradial teeth surrounding the mouth. The latter is
armed in two other species with two teeth, and in one species with four teeth (compare
above, p. 1704). The three perradial feet have a similar position as in the tripodal
NASSELLARIA, so that they may be distinguished as an odd caudal foot and two paired
lateral feet.

Subgenus 1. Tuscarantha, Haeckel.

Definition. — Shell with three perradial equidistant feet and three interradial
equidistant circoral teeth, alternating regularly with the former.

1. Tuscarora bisternaria, John Murray (PI. 100, figs. 1, la).

Tuscarora bisternaria, John Murray, 1879, in litteris, Narr. ChalL Exp., vol. i. p. 226, pi. A,
figs. 16, 16a.

Shell subspherical, with three lateral perradial feet in the equatorial zone, and three basal
interradial teeth around the mouth, alternating regularly with the former. The three lateral feet
arise either in the equator itself or a little above it, and are nearly horizontally expanded, descending
a little towards the aboral pole. They are straight, cylindrical, twice to four times as long as the
shell, geniculate at the inflated base, and covered with small thorns. A circle of six to eight basal
pores in the base of each foot. The narrow mouth is triangular, surrounded by the thorny, inflated,
subspherical bases of the three long, cylindrical, diverging, thorny teeth, which ascend obliquely and
are longer than the shell ; each tooth exhibits in the upper part of the inflated base a corona of
eight to ten ovate holes.

Dimensions. — Length of the shell 2'0, breadth T5.

Habitat. — Central Pacific, Station 264, depth 3000 fathoms.

2. Tuscarora murrayi, n. sp. (PI. 100, fig. 2).

Shell pear-shaped, with three circoral perradial feet in the upper third and three basal
interradial teeth around the mouth. The three lateral feet are thin, cylindrical, arcuate, very
bristly, arise immediately beyond the narrow tubular peristome, and ascend obliquely nearly to the
height of the mouth ; then they are curved downwards in a large arc, three to four times as long as

1 Tuscarora, named from the American ship " Tuscarora," commanded by Captain Belknap, which made a
splendid series of deep-sea soundings in the Pacific Ocean in 1875.

REPORT ON THE RADIOLARIA. 1707

the shell. The tubular peristome is about half as long as the shell, bottle-shaped, nearly three-
sided prismatic, and bears three very long spinulate teeth, which in the lower half are parallel, in
the upper slightly curved and diverging, at the base pear-shaped. Three ovate basal pores in the
inflated base of each foot and each tooth.

Dimensions. — Length of the shell 2'5, breadth 1'5.

Habitat. — South Pacific, Station 295, depth 1500 fathoms.

3. Tuscarora, wyvillei, n. sp. (PI. 100, figs. 3, 3a— 3c).

Shell subspherical, pellucid, thinner and more fragile than in the other species of the genus, with
three aboral perradial feet in the lower third, and three interradlal teeth around the wide mouth.
The three feet are straight, conical, widely divergent, shorter than the shell, and arise from its
lower third ; on the inflated base of each four small ovate pores. The three teeth, alternating
with them, are straight, cylindrical, arise from the margin of the mouth and diverge obliquely
upwards. On the base of each foot four opposite cordate pores of very unequal size.

Dimensions. — Length of the shell 1'5, breadth 1'4.

Habitat. — South Pacific, Station 291, depth 2250 fathoms.

4. Tuscarora tetrahedra, John Murray (PL 100, figs. 4, 4a).

Tuscarora tetrahedra, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i p. 226, pi. A,
fig. 19.

Shell tetrahedral or three-sided pyramidal, with three perradial basal feet, and three alternate,
interradial, circoral teeth. The three rounded edges of the pyramid are prolonged directly over the
aboral base into the three short, divergent, conical, basal feet, which are smooth and scarcely one-
fourth as long as the shell. The base of each foot is pierced by four small crossed pedal pores. The
narrow mouth, on the apex of the pyramid, is surrounded by three short and broad, triangular,
spinulate teeth, each of which bears three slender, triangular, dental pores.

Dimensions. — Length of the shell 2'5, breadth 2'0.

Habitat. — Tropical Atlantic, Station 348, depth 2450 fathoms.

Sub-genus 2. Tuscaretta, Haeckel.

Definition — Shell with three perradial equidistant feet, and with two circoral teeth,
which are opposite in the radius of the odd dorsal foot ; therefore a dorsal and a ventral
tooth.

5. Tuscarora tubulosa, John Murray (PL 100, figs. 5, 5a, 56).

Tuscarora tubulosa, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pL A,
fig. 17.

Shell subspherical, with three lateral perradial feet on the upper half of the shell (above the
equator), and two parallel vertical teeth on the mouth. The three feet arise between the upper and

1708 THE VOYAGE OF H.M.S. CHALLENGER.

the middle third of the shell, diverge upwards, and are slightly arcuate, covered with numerous
curved spines. Their base is pierced by four pedal pores. The peristome is a narrow sagittal
fissure, placed in the radius of the odd or dorsal foot, and bears two opposite teeth on its two
corners. The teeth are cylindrical, longer than the shell, covered with curved spines, and ascend
in a parallel and vertical manner ; each is perforated at the base by three large dental pores.

Dimensions. — Length of the shell 1'4, breadth T2.

Habitat. — North Pacific, Stations 244 to 250, depth 2050 to 3050 fathoms.

6. Tuscarora porcellana, John Murray (PI. 100, figs. 6a, 6&).

Tuscarora porcellana, John Murray, 1879, in litteris, Narr. Chall. Exp., pi. A, fig. 18.

Shell pear-shaped, with three lateral perradial feet in the lower half of the shell, and two
parallel vertical teeth on the mouth. The three lateral feet arise between the middle and the
lower third of the shell, are straight, cylindrical, spinulate, about as long as the shell and diverge
downwards ; their base is pierced by four ovate pedal pores. The two parallel and vertical teeth
are straight, shorter than half the shell, and opposite in the sagittal plane, on the two corners of the
narrow mouth, in the radius of the dorsal odd foot. The base of each tooth exhibits four cordate
dental pores.

Dimensions. — Length of the shell l-5, breadth T3.

Habitat. — South Atlantic, Station 325, depth 2650 fathoms.

Subgenus 3. Tuscarilla, Haeckel.

Definition. — Shell with three perradial equidistant feet, and with four crossed
equidistant teeth around the mouth.

7. Tuscarora belknapii, John Murray.

Tuscarora belknapii, John Murray, 1879, in litteris, Narr. ChalL Exp., vol. i. p. 226, pi. A,
figs. 15, I5a-I5d.

Shell pear-shaped, with three lateral perradial feet in the upper third, and four crossed teeth
around the mouth. The three arcuate feet are thin, cylindrical, covered with small curved thorns,
and arise at the base of the peristome, between the upper and middle third of the shell ; they ascend
diverging to the height of the mouth, and are then curved downwards in a large arc, twice to three
times as long as the shell. The base of each foot is dilated and pierced by three pedal pores. The
four thin and long teeth of the peristome are similar to the feet, ascend in a slightly diverging
manner, and are so placed that two opposite lie in the sagittal plane (or in the radius of the dorsal
odd foot), whilst the two others are opposite in the frontal plane (perpendicular to the former).
The base of each tooth exhibits two large ovate dental pores.

Dimensions. — Length of the shell 2 '5, breadth 1'5.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

REPORT ON THE RADIOLARIA. 1709

Genus 718. Tuscarusa,1 n. gen.

Definition. — T uscarorida with four radial aboral feet and a variable number of
circoral teeth.

The genus Tuscarusa differs from the preceding closely allied Tuscarora in the
possession of four radial feet instead of three. The mouth of the single observed
species is a narrow sagittal fissure, and armed with two opposite teeth (a dorsal and a
ventral, as in the subgenus Tuscaretta). The four lateral feet form a cross, and lie
opposite in pairs, in two diagonals of the square, which is bisected by the sagittal mouth.

1. Tuscarusa medusa, n. sp. (PL 100, figs. 7, 7a).

Shell ovate, with four crossed lateral feet in the upper third, and with two opposite teeth around
the mouth. The four feet are opposite in pairs in two diameters of the shell, perpendicular one to
another, and arise between the upper and middle third of the shell; they are thin, cylindrical, spinulate,
arcuate, and ascend to the height of the mouth diverging upwards; then they are curved downwards
in a large arc. They lie in the diagonals of the square, which is halved by the narrow and long
fissure of the mouth. This lies in the original sagittal plane, and from its two corners arise the two
opposite teeth (a dorsal and a ventral), diverging upwards, cylindrical and slightly curved. The
base of each foot is pierced by four pedal pores, of each tooth by two dental pores.

Dimensions. — Length of the shell 1'2, breadth I'D.

Habitat. — North Pacific, Station 253, depth 3125 fathoms.

Genus 719. Tuscaridium,2 n. gen.

Definition. — T uscarorida without radial aboral feet, but with a terminal axial
caudal foot, and a variable number of circoral teeth.

The genus Tuscaridium, comprising two closely allied species, differs from the two
preceding genera of Tuscarorida in the absence of lateral radial feet, which are repre-
sented by a single large caudal spine placed in the main axis of the shell, at its aboral
pole. The shell is therefore spindle-shaped, and not ovate or subspherical, as in the
two other genera. It reaches in the two observed species a length of more than
3 mm.

1. Tuscaridium cygneum, Haeckel.

Tuscarora. cygnea, John Murray, 1879, in litteris, Narr. Chall. Exp., vol. i. p. 226, pi. A, fig. 20.

Shell spindle-shaped, twice as long as broad (in the transverse section circular), equally tapering
towards both poles of the main axis. The aboral pole bears a thin, cylindrical, straight, caudal
1 Tuscarusa, derivation from Tuscarora. 2 Tuscaridium, derivation from Tuscarora.

1710 THE VOYAGE OF H.M.S. CHALLENGER.

spine, placed in the prolongation of the main axis, and about half as long as the shell. Its base is
pierced by two large opposite pedal pores. The anterior or oral pole bears a cylindrical peristome,
similar to a bird's head, and curved towards the ventral face ; on both sides of its neck (at right
and left) a series of three or four irregular, ovate, buccal holes. The neck bears four cylindrical,
spinulate, radial tubes (two on each side), crossed nearly horizontally, and placed in two diagonal
planes perpendicular one to another ; these planes correspond to those in which the four feet of
Tuscarusa medusa lie. The base of each tube is pierced by four dental pores.

Dimensions. — Length of the shell 3 '2, breadth 1'6.

Habitat. — North Pacific, Station 250, depth 3050 fathoms.

2. Tuscaridium lithornithium, n. sp. (PI. 100, figs. 8, 8a, 86).

Shell spindle-shaped, twice as long as broad, very similar to the preceding closely allied species.
It differs from the latter in the following characters : — The curved proboscis of the peristome is
broader and more spiny. The four radial tubes of the mouth and the terminal caudal spine are very
spiny (in the preceding species nearly smooth). The number of buccal holes (six to eight on each
side of the mouth) is twice as great as in the former. Each circoral tube is pierced at the base by
six or eight (in the former by four pores), and the base of the caudal spine exhibits a cross of four
pores (in Tuscaridium cygneum only two pores).

Dimensions. — Length of the shell 3-6, breadth l-8.

Habitat. — North Pacific, Station 264, depth 3000 fathoms.

Order IV. PILEOCONCHIA, Haeckel, 1879.

Definition. — PH^EODARIA with a bivalved lattice-shell, composed of two free opposite
valves (a dorsal and a ventral), between which the central capsule is enclosed.

Family LXXXIII. CONCHARIDA, Haeckel, 1879 (Pis. 123-125).
Coneharida, Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch. Jena, Dec. 12, p. 6.

Definition. — PH^EODAEIA with a bivalved lattice-shell, which is spherical or lenticular,
and composed of two equal or unequal boat-shaped valves, a dorsal and a ventral. The
valves bear neither an apical latticed cupola or galea, nor hollow radial tubes. The
central capsule is placed in the aboral half of the shell-cavity, and so enclosed between
both valves, that its three openings lie in the open frontal fissure between them (the
astropyle on the oral pole of the main axis, the two parapylse on both sides of its aboral
pole, at right and left).

REPORT ON THE RADIOLARIA. 1711

The family Concharida and the two following closely allied families, the Coelo-
dendrida and Ccelographida, compose together the most remarkable and interesting
suborder ofPhseoconchia (or " PH^ODARIA bivalva "), differing from all the other
Radiolaria in the possession of a bivalved lattice-shell, composed of two separate valves,
like the shell of a Brachiopod. The central capsule is so enclosed between the two
fenestrated valves that its three openings lie in the horizontal open (frontal) fissure
between them, the astropyle or main-opening on the oral pole of the main axis ; the
two secondary openings or parapylse on the two sides of its aboral pole, at right and
left. The plane in which the three openings lie is therefore the frontal plane, dividing
the entire body into a dorsal and a ventral half. The two valves, accordingly, must
be considered as dorsal and ventral valves (as in the Brachiopoda), and the symme-
trical halves of each valve as right and left. These halves may be always easily
distinguished, since the oral pole of each valve is constantly different from the aboral
pole. The voluminous phseodium always lies in the oral half, and the central capsule in
the aboral half of the shell-cavity, whilst the calymma encloses the whole shell.

The Concharida differ from the other two families of bivalved PH^EODARIA in the
absence of the apical galeas, and the branched hollow tubes arising from them. Each
of these two cupolas, which are at the opposite poles of the sagittal axis (one cupola on
the apex of each valve), is in the Coelographida connected by a simple or double frenulum
with a peculiar rhinocanna, or an open nasal tube directed towards the mouth ; whilst
the cupolas of the Ccelodendrida possess neither a rhinocanna nor a frenulum. The three
families of Phseoconchia may therefore represent a phylogenetical series, the
common root of which are the Concharida. From these are developed the Ccelodendrida
by development of an apical cupola or galea on each valve, and of hollow radial tubes
arising from it ; whilst the Ccelographida are developed from the latter by production of
a rhinocanna on the base of each cupola, and of one or two frenula connecting the
former with the latter.

All the Concharida described in the following pages (seven genera and thirty
species), are perfectly new to science, and not a single form of this interesting family
was known before the explorations of the Challenger. Some species (mainly of the
genera Conchidium and Conchopsis) are by no means rare, and are found in great
numbers at some stations of the tropical seas (in the Pacific as well as in the Atlantic).
All described species are closely allied, agree in the majority of characters, and are
easy to distinguish from all the other Radiolaria. Some few forms of Concharida,
however, form a direct passage to the Ccelodendrida.

Regarding the probable origin of the Concharida (and therefore also of all other
Phseoconchia derived from the latter), two different hypotheses are possible.
They have either been derived directly from the skeletonless Phceodina, by development
of a bivalved lattice-shell ; or they may be derived from PH/EODARIA with a simple

1712 THE VOYAGE OF H.M.S. CHALLENGER.

spherical lattice-shell (Castanellida), by the halving of this latter, or its splitting into
two hemispherical valves ; the former hypothesis is more probable than the latter.

The two valves of the lattice-shell (Pis. 123-126) must in the Concharida (as in
all other Phseoconchia) be distinguished as dorsal and ventral, and may therefore
be compared with the two valves of the Brachiopoda, not with those of the Lamelli-
branchia. This important morphological distinction is expressed by the constant
position of the central capsule within the shell-cavity. The capsule always exhibits
the character of the " TRIPYLEA " and has three tubular openings, placed in the frontal
or lateral plane of the unicellular body. In the same plane lies the open frontal
fissure between the two valves, and the three openings are so disposed in it that the
large anterior main-opening (or the astropyle) is placed on the oral pole of the main
axis, whilst the two accessory small lateral openings or parapylse are placed on both
sides of the aboral pole, at the right and left. Therefore in a dorsal or ventral
view all three openings are visible (PI. 123, figs. 1, 8a) ; in the usual lateral view,
however, from the right or left side, only two openings are visible, the astropyle on
the anterior, and one parapyle (right or left) near the posterior pole of the main axis
(PI. 123, figs. 8, 9; PI. 124, figs. 6, 10). The posterior view (from the aboral pole)
shows the two parapylse, at right and left ; in the anterior view (from the oral pole)
the astropyle may be visible, but usually it is completely hidden in the dark
voluminous phaeodium. This latter envelops sometimes nearly the whole capsule as an
opaque conglomeration of green or brown phseodella (PI. 123, figs. 8, 9); but usually
the phgeodium fills up the anterior (oral) half of the shell-cavity, whilst the capsule
occupies the posterior (aboral) half (PL 124, figs. 6, 10).

The dorsal shell-valve is in almost all PH^EODABIA smaller or somewhat different in
shape from the ventral valve, and this difference is often very striking (PI. 124,
figs. 3-16); but in a few species both valves are so similar, that I could not discover
any certain difference. This equality of the two valves occurs mainly in those
Concharida which pass over into the Ccelodendrida ; in these latter as well as in the
Coelographida, both valves are usually equal in size and form. Whilst the main axis
(or the longitudinal axis of the body) in the two latter families of Phseoconchia
seems to be normally vertical (in the living and -freely floating body), in the living
Concharida it is probably horizontal, so that the larger and heavier ventral valve lies
below the smaller and lighter dorsal valve.

The geometrical fundamental form of the body is therefore in the Concharida
dipleural or bilaterally symmetrical, and we distinguish in it the same three dimensive
axis, as in all other dipleural forms. On the anterior or oral pole of the main axis (or
longitudinal axis) lies the mouth of the shell, and behind it the phseodium ; on the
opposite posterior or aboral pole lies the hinge of the shell (comparable to the shell-
hinge of the Brachiopoda) and in front of it the central capsule. The sagittal (or dorso-

REPORT ON THE RADIOLARIA. 1713

ventral) axis, determining the height of the shell, has on its dorsal (or upper) pole
the apex or highest point of the dorsal valve, on its ventral (or lower1) pole the apex or
lowest point of the ventral valve. The two poles of the frontal (lateral or transverse)
axis are equal and are determined by the two parapylse of the capsule, and the corre-
sponding points of the shell-fissure between both valves. Usually the main-axis is the
longest, the frontal axis the shortest, and between both the sagittal axis. •

In regard to the three dimensive planes which are determined by these three axes,
perpendicular to one another, they are rarely of nearly equal size (as in some subspherical
species), usually the sagittal plane (separating the right and left halves of the body) is the
largest ; the cinctural or equatorial plane (separating oral and aboral halves) is the
smallest, and the frontal or lateral plane (separating dorsal and ventral halves) is
intermediate in size. The relation of the three perimeters of these three planes
corresponds to that proportion ; the sagittal perimeter (in which the keel of the
compressed valves lies) is the largest ; the cinctural or equatorial perimeter (separating
the anterior phseodium and the posterior central capsule) is the smallest, and the
frontal or lateral perimeter (in which the fissure between the valves lies) is intermediate
in size.

The general form of the single valves is very varied in the different species, in the
majority boat-shaped or hat-shaped, more or less laterally compressed, in a few forms
hemispherical. In Conchopsis (PI. 125) and Conchoceras (PL 124, figs. 15, 16) the
lateral parts of the valves (right and left) are vaulted, whilst their median parts are so
strongly compressed that they form a sharp sagittal keel, and then the shell in the
dorsal or ventral view appears spindle-shaped (PI. 123, fig. 8a ; PI. 125, fig. 8).
Often the frontal margins of the valves are somewhat constricted (PL 1 24, fig. 7).

The junction between the two valves of the shell is always loose, but not so loose
as in the two following families. In the Coslodendrida and Ccelographida the two
valves are either perfectly free and separated by a frontal zone of jelly, or in very
loose contact on the frontal margins. In the Concharida, however, the margins of both
valves seem to be usually in contact, and their connection is effected in a double way.
In the subfamily Conchasmida (comprising the genera Concharium and Conchasma,
PL 123, figs. 1—6) the lateral margins of both valves are smooth, not dentated, and
fit one into another like the two parts of a box, or like the two valves of a Diatom
(Navicula). In the second subfamily, however, Conchopsida (comprising the five
other genera, Pis. 124, 125), the lateral margins of the valves are dentate, usually
provided with a series of numerous strong conical teeth, and the teeth of both valves
so catch into one another, that their union is rather firm (like the margin of the shells of
Tridacna, Pecten, and other Lamellibranchiata). Besides, a more solid junction is often
effected on the posterior or aboral part of the margins, which we shall call the hinge.
Here often peculiar strong teeth catch one into another, and in the majority of species

(ZOOL. CHALL. EXP. — PART XL. — 1886.) Rr 215

1714 THE VOYAGE OF H.M.S. CHALLENGER.

two aboral spines are developed, the caudal horns (a dorsal and a ventral) ; these are
very large in Conchoceras (PL 124, figs. 15, 16). But a peculiar and most interesting
kind of junction is effected in some Concharida by a true ligament between the valves
(PI. 123, figs. 8, 9 ; PI. 125, fig. 2). This ligament is always placed on the aboral
hinge, is of dark brown colour, and is not dissolved by mineral acids unless long applied.
"It may preserve the connection of the posterior parts of both valves, when their anterior
parts are removed one from another, just as in the Brachiopoda. I observed this
interesting ligament mainly in the genus Conchopsis, but not in all species, and it
is not yet certain whether it is a constant organ in these and some other Concharida.

In the majority of Concharida the lateral margins of the two valves project slightly
inwards into the cavity, and in some species of Conchopsis these inner borders are so
broadened that they form a broad, horizontal, fenestrated inner shelf, comparable to
the deck of a boat or to the velum of the Hydromedusse or Craspedotse (PI. 125,
fig. 9). In this case the velum surrounds the ovate aperture through which the two
lobes of the central capsule (dorsal and ventral) enter into the cavity of both valves.

The mouth of the shell lies on the oral pole of the main axis, and is therefore
opposed to the aboral hinge. The two valves are here usually more or less emarginate,
so as to form a transverse mouth with an upper and a lower lip (PL 124, figs. 6, 7, 11).
The form of these two lips is often very different and characteristic of particular species
(PL 124, figs. 3, 15, 16). The mouth remains in many species constantly open, even
when the frontal fissure is closed (figs. 7, 16). Since the centre of the shell mouth lies
in the prolongation of the proboscis arising from the operculum of the central capsule,
probably the mam stream of sarcode, issuing from the latter, becomes protruded by the
former.

Apophyses of the shell (besides the teeth of the margins) are completely wanting
in three genera, Concharium, Conchellium, and Conchopsis (PL 123, figs. 1—4, 7;
PL 125). The four other genera possess free apophyses or spines, which we call
horns. They are probably important as the beginnings of those large hollow
tubes which are characteristic of the two following families, Ccelodendrida and
Coelographida. We distinguish two different forms of horns, apical horns on the poles
of the sagittal axis, and caudal horns on the aboral pole of the main axis ; the former
probably correspond to the sagittal tubes and the latter to the caudal tubes of the two
following families. Apical horns are found in a single genus only, Conchonia
(PL 124, figs. 10—14). Here either on one pole or on both poles of the sagittal axis
a horn is developed, usually curved backwards. Sometimes the base of this conical
horn is inflated and fenestrated, and may represent the beginning of the formation
of the galea or apical cupola of the Ccelodendrida.

The two caudal horns are opposite on the aboral hinge of the shell, one arising from
the posterior end of each valve. Usually they are short and thick, pyramidal, the

REPORT ON THE RADIOLARIA. 1715

ventral horn larger than the dorsal (PL 124, figs. 3, 6). Rarely the two caudal horns
are fenestrated at the base and reach a considerable size, as in Conchoceras (PL 124,
figs. 15, 16).

The walls of the bivalved shell usually exhibit in the Concharida a rather solid
shape and regular structure, with an elegant network of regularly arranged pores. But
in some species the walls of the shell become very thin and fragile, and assume the
same shape .(with very irregular network), as in the Ccelodendrida and Coelographida.
The pores are usually small and numerous, circular, often hexagonally framed (PL 125,
figs. 4-6). They pierce the thick shell-wall either in a radial or in an oblique direction.
Sometimes each pore is armed with six radial teeth (PL 123, fig. 7a). At other
times each pore represents an oblique ampullaceous canal, dilated in its middle part,
with two narrow openings (PL 125, figs. 5 a, b, c, 6). The pores are so arranged in the
majority of species that they form regular curved series, which are separated by
prominent crests, and converge towards the poles of the main axis. Usually the
marginal pores (along the frontal margins of the valves) are much smaller (compare
Pis. 123-125).

The central capsule of the Concharida, very well preserved in numerous specimens
of the Challenger collection, constantly possesses the same situation and structure. It is
always enclosed in the aboral or posterior half of the shell-cavity, whilst the oral or
anterior half is filled up by the phseodium. The free spaces between both and between
the inner surface of the shell are completely filled up by the jelly of the calymma, which
also covers the whole shell as a thin outer jelly-envelope. The form of the central
capsule is sometimes nearly spherical, usually somewhat compressed in the direction of
the main axis, and sometimes also in the direction of the frontal axis (PL 123,
figs. 1—9). In some species it becomes bilobed, with an upper dorsal and a lower
ventral lobe, and in some others it becomes triangular (PL 125, fig. 7). Its two
membranes (inner and outer) are often separated by a broad colourless interval, contain-
ing a clear fluid or jelly (PL 123, figs. 8, 9). The nucleus is usually about half as
large as the central capsule and ellipsoidal, its longer axis lying in the sagittal diameter
of the body. Several specimens (of different genera) contained two separate nuclei, one
placed in the dorsal, the other in the ventral half of the capsule (PL 124, fig. 6).
This duplication of the nucleus is probably the preparation for the division of the
capsule. The division will be probably effected in the frontal plane, so that each half
of the bisected capsule gets one nucleus and one valve, and the other valve becomes
newly formed (in a way similar to that in the bivalved Diatomacese). The astropyle, or
the main-opening of the capsule, is closed by a radiate operculum, from which arises a
tubular proboscis ; this lies in the main axis of the body, is directed towards the anterior
mouth of the shell, and surrounded by the phseodium. The two shorter tubes of the
paired parapylse, or the accessory lateral openings, lie on the posterior or caudal side of

1716

THE YOYAGE OF H.M.S. CHALLENGER.

the capsule, at right and left, and are directed half backwards, half outwards (towards
the frontal fissure between the valves, PI. 123, figs. 1, 8 a).

The phseodium exhibits in all Concharida the same characteristic shape, and
represents a dark conglomeration of phseodellse, filling up the anterior or oral half of the
shell-cavity. Usually it is bilobed, divided into a dorsal and a ventral lobe or wing,
which fills up the corresponding valve of the shell (PI. 123, figs. 8, 9). The phseodium
is commonly more voluminous than the capsule, and surrounds its anterior half, more
rarely it encloses nearly the entire capsule (PL 124, figs. 6, 10). Its colour is usually
olive, sometimes more greenish, at other times more brownish, in some species nearly
black. The phseodellse, or the roundish granules which compose the phseodium, exhibit
the same shape as in all other PH^ODARIA (compare above, p. 1535). Sometimes
peculiar rather oblong nucleated cells are scattered in great numbers between the
phseodellae, probably parasites or symbiontes (PI. 123, figs. 7-9, 9a).

Synopsis of the Genera of Concharida.

I. Subfamily

Conehasmida.
Lateral edges of the
two valves smooth,
without teeth.

II. Subfamily

Conchopsida.

Lateral edges of the
two valves dentate,
with a series of
prominent teeth on
both sides. The
teeth of both valves
catch one into an-
other.

Valves without sagittal keel,
nearly hemispherical or
slightly compressed.

Valves without sagittal keel,
nearly hemispherical or
slightly compressed.

Valves with a sharp sagittal
keel, strongly compressed
on both sides, boat-
shaped.

Aboral hinge without horns, . 720. Coneharium.

I

Aboral hinge with two horns
(one on each valve),

Aboral hinge without horns, .

Aboral hinge with two horns.
No apical horn,

Aboral hinge with two horns.
Apex also with a horn,

Aboral hinge without horns, .

Aboral hinge with two horns
(one on each valve).

721. Conchasma.

722. Concheltium.

723. Conchidiuiu.

724. Conchonia.

725. Conchopsis.

726. Conchocera*.

Subfamily 1. CONCHASMIDA, Haeckel.

Definition. — C oncharida with the lateral margins of the two valves smooth, with-
out interlocking teeth.

Genus 720. Concharium,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C oncharida with the lateral margins of the valves smooth, without
sagittal keel and without horns on the hinge.

1 Conchariwm = Small mussel ;

REPORT ON THE RADIOLARIA. 1717

The genus Concharium is the simplest and the most primitive form of all
Concharida ; it may be regarded as the common ancestral form of the whole family.
The entire shell is usually almost spherical, without horns or teeth, and may be
regarded as a Castanella which is bisected or broken into two equal hemispherical
halves. The lateral margins of the two hemispherical valves are smooth, without teeth,
and catch one into the other like the two valves of a Diatom, or the two halves of a
bivalved box. Concharium agrees in this simple shape of the frontal margins with the
following genus Conchasma, and represents with it the small subfamily Conchasmida.

1. Concharium bivalvum, n. sp. (PI. 123, figs. 2, 2a).

Shell spherical, smooth. Diameter in all directions nearly the same. Borders of the two
hemispherical valves circular, smooth, about twice as broad as the pores. In the half frontal
perimeter of the shell (along the right and the left border of each valve) twenty-two to twenty-four
pores, in the half sagittal perimeter (in the middle line of each valve) eighteen to twenty-two pores,
in the half equator (in the cinctural perimeter of each valve) twenty to twenty-two pores. All
pores circular, of the same size, twice as broad as their bars.

Dimensions. — Length of the shell (longitudinal diameter) 0'35, height (sagittal diameter) 0'34,
breadth (lateral diameter) 0'33.

Habitat. — North Atlantic, west of Madeira, Station 354, depth 1675 fathoms.

2. Concharium nucula, n. sp. (PL 123, fig. 3).

Shell pear-shaped, with costate surface. Oral face somewhat truncated, broader than the
aboral face. Its longitudinal diameter about one-fifth longer than the two other diameters.
Borders of the two valves ovate, smooth, about as broad as the pores. In the half frontal perimeter
of the shell twenty-two to twenty-four pores, in the half sagittal perimeter eighteen to twenty,
in the half equator sixteen to eighteen. Pores irregularly roundish, three to four times as
broad as the bars. The pores are so disposed in meridional rows that the crests between the rows
converge towards the two poles of the sagittal axis.

Dimensions. — Length of the shell 0'2, height 018, breadth 016.

Habitat. — South Atlantic (west of Tristan da Cunha), Station 332, depth 2200 fathoms.

3. Concharium diatomeum, n. sp. (PL 123, fig. 1).

Shell nearly spherical, slightly lenticular, somewhat compressed in dorso-ventral direction ; the
sagittal diameter therefore somewhat shorter than the two others. Borders of the two hemispherical
valves nearly circular, quite smooth, about as broad as the length of the largest pores. In the
half frontal perimeter of the shell forty-four to fifty pores ; in the half sagittal perimeter twenty to
twenty-four ; in the half equator thirty to thirty-three. Pores different in form and size ; the

1718 THE VOYAGE OF H.M.S. CHALLENGER

marginal pores small, nearly circular ; the dorsal and ventral pores oblongish-hexagonal, twice as
long as broad, about four to six times as long as the bars, regularly arranged in transverse rows.

Dimensions. — Length of the shell 0'22, height 0'21, breadth 0'2.

Habitat. — Tropical Atlantic, near Sierra Leone, Station 348, depth 2450 fathoms.

4. Concharium bacillarium, n. sp. (PI. 123, fig. 4).

Shell walnut-shaped, with panelled surface ; oral and aboral face of the same form. Its
longitudinal diameter about one-fifth longer than the two other diameters. Borders of the two cup-
shaped valves elliptical, smooth, with a prominent edge, about as broad as the larger pores. In
the half frontal perimeter of the shell fifty to fifty-five pores, in the half sagittal perimeter thirty-
six to forty, in the half equator also thirty to forty. Pores hexagonally framed. The pores are
tapering in size from the sagittal plane towards the valve-margins, and so regularly arranged in
meridional rows that the crests between the latter converge towards both poles of the longitudinal
axis.

Dimensions. — Length of the shell 0'2, height 015, breadth 015.

Habitat. — Tropical Atlantic, off St. Helena, Station 340, depth 1500 fathoms.

5. Concharium fragilissimum, n. sp.

Shell subspherical, very thin-walled and fragile. Diameter in all directions nearly the same.
Oral and aboral face scarcely different. Margins of the hemispherical valves extremely thin and
hyaline. Pores irregularly roundish, of very different sizes and unequal forms. The fragile shell of
this species differs in general shape from that of all other Concharida, and is like that of the
Coelodendrida (PI. 121, fig. 3), but exhibits neither an apical cupola or galea, nor radial tubes
arising from it. It may be perhaps a young specimen of Cceloclendrum.

Dimensions. — Diameter of the shell 0'22, of the pores 0'002 to 0-02.

Habitat. — Mediterranean, Portofino (Haeckel), surface.

Genus 721. Conchasma,1 n. gen.

Definition. — C oncharida with the lateral margins of the valves smooth, without
sagittal keel, but with two caudal horns on the hinge (a dorsal and a ventral).

The genus Conchasma is closely allied to the preceding Concharium, and has the
same hemispherical valves with smooth margins, without teeth ; but it differs from the
latter in the development of two caudal horns or posterior spines on the aboral hinge,
one horn on the aboral end of each valve. The three species of this genus were all
found in great depths of the Antarctic Ocean, in Diatom ooze, between 1260 and 1975
fathoms, at Stations 152 to 157.

1 Conchasma = Bivalved shell-fish; xo'/x»afta.

REPORT ON THE RADIOLARIA. 1719

1. Conchasma radiolites, n. sp. (PI. 123, fig. 5).

Shell nearly spherical, somewhat compressed on both sides ; the dorsal valve smaller, flatter
and shorter than the ventral valve. In the half sagittal perimeter of the shell twenty to twenty-two
pores, in the half frontal perimeter twelve to fourteen, in the half equator eighteen to twenty.
All pores nearly of the same size, circular, hexagonally framed, scarcely as broad as the bars. The
two horns of the hinge are four-sided pyramidal, of different sizes ; the ventral horn (of the larger
valve) two to three times as long as the dorsal horn (of the smaller valve) ; the latter twice as long
as a pore.

Dimensions. — Length of the shell 016, height 015, breadth 014.

Habitat. — Antarctic Ocean, Station 154, depth 1800 fathoms.

2. Conchasma sphcerulites, n. sp. (PI. 123, fig. 6).

Shell nearly spherical, somewhat compressed on both sides, the frontal diameter therefore
somewhat shorter than the two others. Both valves nearly of the same size, hemispherical, their
borders smooth, twice as broad as the largest pores. In the half sagittal perimeter of the shell
twenty-eight to thirty pores, in the half frontal perimeter twenty to twenty-two, in the half equator
twenty-four to twenty-six. Size of the pores increasing from the borders towards the top of the
valves. One series of very small pores along the frontal free margin of each valve. Pores roundish-
polygonal, three to four times as broad as the bars. The two horns of the hinge are of equal size,
four-sided pyramidal, and twice as long as the larger pores.

Dimensions. — Length of the shell 018, height 018, breadth 016.

Habitat. — Antarctic Ocean, Station 152, depth 1260 fathoms.

3. Conchasma hippurites, n. sp.

Shell nearly spherical, scarcely compressed. The frontal diameter equal to the two others.
Both valves equal. In the half sagittal perimeter of the shell thirty-two to thirty-four pores, in
the half frontal perimeter twenty-four to twenty-six, in the half equator twenty-six to twenty-eight.
All pores of nearly equal size, circular, polygonally framed, twice as broad as the bars. The two
horns of the hinge are large, three-sided pyramidal, the ventral horn twice as long as the dorsal, and
four to six times as long as one pore.

Dimensions. — Length of the shell 0'22, height 0'21, breadth 0'2.

Habitat. — Antarctic Ocean, Station 157, depth 1950 fathoms.

Subfamily 2. CONCHOPSIDA, Haeckel.

Definition. — C oncharida with the lateral margins of the two valves dentate, the
teeth of both catch one into another.

1720 THE VOYAGE OF H.M.S. CHALLENGER.

Genus 722. Co'fichellium,1 n. gen.

Definition. — C oncharida with the lateral margins of the valves dentate, without
sagittal keel and without horns on the hinge.

The genus Conchellium and the four following genera represent together the sub-
family Conchopsida, differing from the Conchasmida in the dentate lateral margins of
the two valves. These are armed with a series of strong, conical teeth, and catch one
into another just as the two valves of many Lamellibranchiata and Brachiopoda do
(PI. 124, figs. 1—16). Conchellium is the simplest form among the Conchopsida,
since the valves are hemispherical, and possess neither a sagittal keel nor projecting
horns.

1. Conchellium tridacna, n. sp. (PL 123, figs. 7, 7a).

Shell nearly spherical, finely tuberculated, the sagittal diameter somewhat longer than the two
others. Borders of the two hemispherical valves smooth in 0'2 of the oral, and 01 of the aboral
part, dentated in the remaining 0'7 part ; on one side of each valve fourteen to sixteen very strong
and long teeth, all nearly of the same size, about one-fourth as long as the shell-radius. In the
half frontal perimeter of the shell (on one border of each valve) twenty-five to thirty pores, in the
half sagittal perimeter thirty-five to forty, in the equator twenty-five to thirty. Pores circular,
hexagonally framed, of equal size (except some smaller rows along the fissure), twice as broad as the
bars. On the conical inside of each funnel-like pore six small spinules, between every three
neighbouring pores a triangular facette (fig. 7a).

Dirnensions. — Length of the shell 0'34 to 0-38, height 0'38 to 042, breadth 0'32 to 0'36.

Habitat. — North Pacific, Stations 250 to 253, depth 2740 to 3125 fathoms.

2. Conchellium hippopus, n. sp.

Shell nearly spherical, in the lateral perimeter (along the girdle-fissure) somewhat constricted.
Borders of the two hemispherical valves semicircular, smooth in 0'3 of the oral, and 0'2 of the
aboral part, dentated only in the remaining 0'5 middle part ; on one side of each valve seven to
eight very strong and long teeth, increasing in size towards the mouth, the longest (foremost) teeth
•nearly one-third as long as the shell-radius. In the half frontal perimeter of the shell (along one
border of each valve) twenty-four to twenty-eight pores, in the half sagittal perimeter thirty-two to
thirty-six, in the half equator twelve to fourteen. Pores circular, twice to three times as broad as
the bars, smaller along the fissure.

Dimensions. — Length of the shell 0'06, height 0'065, breadth 0'055.

Habitat. — Central area of the Tropical Pacific, Station 274, depth 2750 fathoms.

1 Conchellium = Small bivalved mussel ;

REPORT ON THE RADIOLARIA. 1721

Genus 723. Conchidium,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C oncharida with the lateral margins of the valves dentate, without
sagittal keel and apical horns, but with two caudal horns on the hinge (a dorsal and
a ventral).

The genus Conchidium is the most common form of all Concharida, and some of
its species occur in great numbers in the tropical zone of the Pacific and the Atlantic,
on the surface as well as at various depths. It differs from the preceding Conchellium,
its ancestral form, in the development of two caudal horns, or two strong pyramidal
spines which arise from the posterior end of the valves ; the dorsal horn usually is
smaller than the ventral.

1. Conchidium terebratula, n. sp. (PI. 124} figs. 1, 2).

Shell subspherical, smooth ; both valves of nearly equal size and form, hemispherical. The
three dkuensive axes of the body are almost equal. Margins of the valves dentate in nearly the
whole periphery ; on each side of one valve eleven or twelve strong conical teeth, all of the same
size. Aboral hinge with two short and stout four-sided pyramidal horns of equal length. Mouth
with two equal short lips. Pores of the shell subregular, circular, three to four times as broad as
the bars, in the dorsal valve twice as large as in the ventral valve.

Dimensions. — Diameter of the shell 0'24 to 0'28.

Habitat. — Central Pacific, Stations 270 to 274, surface, and at various depths.

2. Conchidium thecidium, n. sp. (PI. 124, fig. 6).

Shell subspherical, slightly compressed on both sides. Dorsal valve somewhat smaller than
the ventral, of similar form. Principal axis of the shell somewhat longer than the sagittal, and this
longer than the frontal axis. Margins of the valves smooth in the oral quarter, strongly dentate
in the remainder ; on each side of one valve eight or nine very large triangular teeth, half as
long as the height of the valve. Aboral hinge with two unequal, stout, four-sided pyramidal horns ;
the dorsal horn half as long at the ventral. Mouth with two unequal lips, the upper shorter than
the lower. Pores of the shell subregular, hexagonal, three to four times as broad as the bars. The
figured specimen, well preserved, contained in the central capsule two nuclei, one in the dorsal, the
other in the ventral half.

Dimensions. — Length of the shell 0"28 to 0'33, height 0'27 to 0'3, breadth 0'22 to 0'24.

Habitat.— South Pacific, Station 292, depth 1600 fathoms.

1 Conchidium = Similar to a bivalved mollusc ; xoyxtiioii.

(ZOOL. CHALL. EXP. PART XL. — 188G.) Er 216

1722 THE VOYAGE OF H.M.S. CHALLENGER.

3. Conchidium rhynchonella, n. sp. (PI. 124, fig. 3).

Shell with three different dimensive axes in the proportion = 6:5:4. Ventral valve semi-ovate,
larger than the humpbacked dorsal valve. Margins of the valves dentate almost in the whole
periphery ; on each side of one valve twelve or thirteen strong conical teeth. Aboral hinge with
two 'very unequal horns, the dorsal much smaller than the pyramidal ventral. Under lip of the
mouth emarginate, much larger than the acute upper lip. Pores subregular, circular, twice as
broad as the bars.

Dimensions. — Length of the shell 0'3, height 0'25, breadth 0'2.

Habitat. — North Pacific, Stations 244 to 253, surface, and at various depths.

4. Conchidium dimerella, n. sp.

Shell laterally compressed, very similar to the preceding, but differing in the following
characters : — Proportion of the three axes = 7:5:4. Ventral valve hemispherical, larger than the
humpbacked dorsal. Margins of the valves dentate in the middle half only, whilst the anterior
and posterior quarters are smooth ; on each side of one valve six or seven strong conical teeth.
Ventral horn of the aboral hinge very large, pyramidal, one-third as long as the shell and three
times as long as the dorsal.

Dimensions. — Length of the shell 0'35, height 0'25, breadth 0'2.

Habitat. — North Pacific, Station 236, surface.

• 5. Conchidium leptcena, n. sp. (PI. 124, figs. 4, 5).

Shell laterally compressed, with three different dimensive axes of the proportion = 4:3:2.
Ventral valve larger than the dorsal, both semi-ovate. Margins of the valves dentate along the
lateral sides ; on each side of one valve nine or ten conical teeth, the middle of which are smaller.
Aboral hinge with two unequal short horns ; the dorsal rudimentary. Under lip of the mouth
pointed, much larger than the truncate upper lip. Pores circular, about twice as broad as the bars.

Dimensions. — Length of the shell 0'2, height 015, breadth 01.

Habitat. — Central Pacific, Stations 271 and 272, surface, and at various depths.

6. Conchidium argiope, n. sp. (PI. 124, figs. 7-9).

Shell laterally compressed, with three different dimensive axes of the proportion = 6 : 5 : 3.
Both valves nearly equal. Margins of the shell dentate along the lateral fissure, on each side of
one valve thirteen or fourteen thin conical teeth. Aboral hinge with two equal, short, pyramidal
horns. Mouth with two equal short lips. Pores subregular, circular, twice as broad as the bars.

Dimensions. — Length of the shell 0'2, height 017, breadth 01.

Habitat. — Tropical Atlantic, Stations 341 to 349, surface, and at various depths.

REPORT ON THE RADIOLARIA. 1723

7. Conchidium magasella, n. sp.

Shell laterally compressed, with two equal valves, very similar to the preceding species, but
differing in the following characters : — Proportion of the three axes =6:4:3. Margins of the
valves with smaller and more numerous teeth ; on each side of one valve sixteen to eighteen short
conical teeth. Pores smaller and more numerous, about as broad as the bars.

Dimensions. — Length of the shell 0'24, height 0'16, breadth 0'12.

Habitat. — Indian Ocean, Madagascar (Rabbe), surface.

8. Conchidium productum, n. sp.

Shell laterally compressed, prolonged, with two equal valves, similar to the two preceding
species, differing in the following characters : — Proportion of the three axes = 3:2:1. Margins of
the valves smooth in the anterior and posterior quarter, dentate in the middle lateral half ; on each
side of one valve ten to twelve strong conical teeth. Horns of the aboral hinge prolonged, conical,
half as long as the shell, the ventral somewhat larger than the dorsal. Pores regular, circular, twice
as broad as the bars.

Dimensions. — Length of the shell 0'25, height 015, breadth 0'08.

Habitat. — North Atlantic, Station 354, surface.

Genus 724. Conchonia,1 n. gen.

Definition. — C oncharida with the lateral margins of the valves dentate, without
sagittal keel, but with an apical horn on the poles of the sagittal axis, and with two
caudal horns on the hinge (a dorsal and a ventral).

The genus Conchonia is closely allied to the preceding Conchidium, its ancestral
form, but differs from this and from all other Concharida in the development of horns
on the poles of the sagittal axis. These are probably of great morphological importance,
since they represent the beginnings of the hollow tubes arising from the poles of the
sagittal axis in all Coslodendrida and Ccelographida. In one of the three observed
species each valve possessed an apical or sagittal horn, whilst in the two other species
one valve only was provided with a horn. Since I observed one specimen only of each
species, I cannot say whether this difference is important and of constant generic value.

1. Conchonia diodon, n. sp. (PI. 124, figs. 10-12).

Shell laterally compressed, with two very unequal valves. Dorsal valve smaller, hat-shaped, on
the apex with a fenestrated protuberance which is similar to the galea of the Coelodendrida, and
bears a short, conical, backwardly-directed horn. Ventral valve larger, boat-shaped, without apical

1 (7<mc/wm«z=Bivalved shell like a mussel ; xoyxx, o»«x.

1724 THE VOYAGE OF H.M.S. CHALLENGER.

horn. Aboral hinge with two pyramidal, horizontal, caudal horns of different sizes, the dorsal
smaller than the ventral. Lateral margin of each valve on one side with twelve to fourteen strong
conical teeth (fig. 12). Lips of the narrow mouth thickened (fig. 11).

Dimensions. — Length of the shell 0'3, height 0'27, breadth 0'21.

Habitat. — Tropical Atlantic, Station 342, depth 1445 fathoms.

2. Conchonia triodon, n. sp. (PI. 124, figs. 13, 14).

Shell laterally compressed, with two very unequal valves. Dorsal valve (fig. 14) larger, hat-
shaped, on the apex with a large pyramidal horn which is half as long as the shell, curved and
directed backwards. Ventral valve (fig. 13) smaller, boat-shaped, without apical horn. Aboral
hinge with two pyramidal caudal horns of different sizes, the dorsal horn twice as long as the
ventral. Lateral margin of each valve on one side with twelve to fifteen conical teeth. Perhaps
the larger horned valve (fig. 14) may be the ventral, and the opposite smaller hornless (seen from
above in fig. 13) the dorsal valve.

Dimensions. — Length of the shell 0'21, height 017, breadth 012.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

3. Conchonia tetrodon, n. sp.

Conchura tetrodon, Haeckel, 1882, Manuscript.

Shell subspherical, with two nearly equal hemispherical valves, which are very thin-walled and
similar in structure to those of the Coelodendrida, with very irregular roundish pores of different
shapes and sizes (compare PI. 121, fig. 3). Lateral margins of the valves with very numerous and
irregular, thin, bristle-shaped teeth, similar to those of some Coslographida (compare PI. 127, fig. 8).
Aboral hinge with two equal, conical, caudal horns, which are straight, parallel, and half as long as
the shell. Two similar straight conical horns are opposed on the poles of the sagittal axis, and arise
from the apex of the two valves. This remarkable species may perhaps better represent a separate
genus, Conchura, forming a direct transition to the ancestral form of the Coelodendrida, Ccelodoras ;
it differs from the latter in the absence of a galea or hollow conical cupola on the apex of each
valve, and in the solid, not hollow structure of the horns.

Dimensions. — Diameter of the shell 0'24, length of the two sagittal horns 01, of the two caudal
horns 012.

Habitat. — Indian Ocean, Cocos Islands (Eabbe), surface.

Genus 725. Conchopsis,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C oncharida with dentate lateral margins and a sharp sagittal
keel of the compressed valves, without horns on the hinge.

1 Conchopsis = Similar to a bivalved shell-fish or mussel ;

REPORT ON THE RADIOLARIA. 1725

The genus Conchopsis and the following Conchoceras differ from the other
Concharida in the strong lateral compression of the shell, so that each valve is provided
in the sagittal plane with a sharp prominent keel, comparable to the dorsal and the anal
fin of fishes. These compressed shells are in general twice to three times as large
as the more roundish and keelless shells of the five preceding genera. The sculpture
of the fenestrated valves is extremely elegant. Conchopsis possesses at the aboral
hinge not the two prominent caudal horns, which mark the following genus Concho-
ceras, but in some species a peculiar ligament connects the aboral ends of both valves.

1. Conchopsis orbicularis, n. sp. (PI, 125, fig. 3).

Shell subcircular, lenticular, strongly compressed on both sides, nearly as high as long, its
sagittal perimeter nearly circular ; frontal and cinctural perimeter spindle-shaped. Borders of the
two boat-shaped valves smooth in 0'4 of the oral part, and in 01 of the aboral part of their length,
strongly dentated in the remaining O5 middle part ; about twenty-five slender, straight teeth on
each side of one valve, size of the teeth increasing from the aboral towards the oral pole. In the
half lateral perimeter of the shell (along the right and the left borders of each valve) sixty to sixty-
five pores, in the half sagittal perimeter (along the keel of each valve) eighty to eighty-five pores,
in the half equator sixty to sixty-five pores.

Dimensions. — Length of the shell 0'53, height 0'55, breadth about 0-2.

Habitat. — South Atlantic, west of Tristan da Cunha, Station 333, depth 2025 fathoms.

2. Conchopsis compressa, n. sp. (PI. 125, figs. 7, 8).

Shell lenticular, strongly compressed on both sides ; proportion of its longitudinal diameter to
the sagittal and lateral = 10 :9 : 3, its sagittal perimeter elliptical (fig. 7), cinctural and frontal
perimeter spindle-shaped (fig. 8). Borders of the two boat-shaped valves smooth in 0'3 of the oral,
and 0'3 in the aboral part, dentated in the remaining 0'4 middle part ; about forty to forty-four very
slender teeth of equal size on one lateral edge of each valve. In the half frontal perimeter of the
shell (along the border of the valve) sixty-four to sixty-eight pores, in the half sagittal perimeter
(along one valve-keel) seventy to eighty pores, in the half equator forty-four to forty-eight pores.
Ventral and dorsal pores linear, three to four times as long as the circular, lateral pores.

Dimensions. — Length of the shell 0'6 to 0'8, height 0'55 to 0'72, breadth 0'2 to 0'3.

Habitat. — North Pacific, between 30° and 40° north latitude (between Japan and San Francisco),
in depths from 2000 to 3000 fathoms frequent, Stations 241 to 252.

3. Conchopsis carinata, n. sp. (PL 123, fig. 8).

Shell subcircular, lenticular, in the central half slightly compressed, nearly spherical, in the
peripheral half strongly compressed, with a broad, hyaline, smooth keel on the sagittal plane.
Borders of the two valves smooth in the 0'2 of the oral, and O'l of the aboral part, strongly

1726 THE VOYAGE OF H.M.S. CHALLENGER.

dentated in the remaining 0'7 middle part ; about fifty slender teeth of equal size on one lateral
edge of each valve. In the half lateral perimeter of the shell about forty-five to fifty pores, in the
half sagittal perimeter sixty-five to seventy, in the half equator thirty-two to forty pores. The
pores are arranged in parallel curved rows, which are separated by high denticulate crests. Aboral
hinge with a strong ligament.

Dimensions. — Length of the shell 0'6 to 0'7, height 0'55 to 0'65, breadth 0'35 to 045.

Habitat. — South Atlantic (east of Patagonia), Station 318, depth 2040 fathoms.

*

4. Conchopsis lenticula, n. sp. (PL 123, fig. 9).

Shell subcircular, lenticular, strongly compressed on both sides, with a sharp and broad
hyaline keel in the sagittal perimeter. Borders of the two valves smooth in 0'3 of the oral,
and 0'2 of the aboral part, strongly dentated in the remaining 0'5 middle part ; about thirty strong,
conical teeth on the lateral edge of each valve. In the half lateral perimeter of the shell fifty to
fifty-five pores, in the half sagittal seventy to seventy-five, in the half frontal forty to forty-five
pores. The large central capsule of this species fills up the posterior half of the shell-cavity, the
dark green phseodium the anterior half ; the latter contains numerous peculiar, longish, nucleated
cells (fig. 9a), parasites or symbiontes (?). Aboral hinge of the shell with a strong ligament.

Dimensions. — Length of the shell 0'7, height 0'6, breadth 0'3.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

5. Conchopsis pilidium, n. sp. (PI. 125, fig. 9).

Shell ovate, lenticular, compressed on both sides, with a broad, wing-like sagittal keel.
Proportion of its longitudinal diameter to the sagittal and lateral = 6:5:3. Sagittal perimeter
elliptical. Borders of the two hat-like valves smooth in 015 of the oral, and 0'2 of the aboral part,
strongly dentated in the remaining 0'65 middle part ; about twenty-five to thirty teeth of nearly
equal size on one side of each valve. In the half lateral perimeter of the shell (along one border
of each valve) forty-five to fifty pores, in the half sagittal perimeter (on the keel of one valve)
seventy to seventy-five pores, in the half equator thirty-six to forty pores. Each pore is surrounded
by a hexagonal frame. The opening of each valve in this species is bordered and partly closed by
a broad, horizontal diaphragm or velum, like the deck of a boat ; it is broadest on the oral
side.

Dimensions. — Length of the shell 0'7'8 to 0'8, height 0'66 to 0'7, breadth 0'3 to 0'4.

Habitat. — South Atlantic, between Buenos Ayres and Tristan da Cunha, Stations 324 to 334,
at depths between 1715 and 2900 fathoms.

6. Conchopsis aspidium, n. sp. (PI. 125, figs. 1, 2).

Shell scutiform, strongly compressed on both sides, in the centre only lenticular, in the
periphery wing-like, keeled. Proportion of the longitudinal diameter to the sagittal and frontal
= 6:5:2. Sagittal circumference in the oral half semicircular, in the aboral half pentagonal, two

REPORT ON THE RADIOLARIA. 1727

acute corners jutting out near the aboral hinge, one corner in the keel of the dorsal, the
outer in the keel of the ventral valve. Borders of the two boat-shaped valves smooth in 0'3 of
the oral part, and in O'l of the aboral part, strongly dentated in the remaining 0'6 middle part ;
about thirty-five teeth in one side of each valve, larger on both ends than in the middle. In
the half frontal perimeter of the shell sixty to sixty-five pores, in the half sagittal perimeter
eighty to eighty-five, in the half equator of the shell forty to fifty pores.

Dimensions. — Length of the shell 0'55 to 0'65, height 0'5 to 0'55, breadth 0'2 to 0'22.

Habitat. — North Pacific, Stations 243 and 244, depth 2800 to 2900 fathoms.

•

7. Conchopsis navicula, n. sp. (PL 125, figs. 4—6).

Shell pear-shaped, compressed on both sides, in the sagittal periphery keeled. Proportion of
the longitudinal diameter to the sagittal and lateral = 4:3:2. Its sagittal perimeter nearly ovate.
Borders of the two boat-shaped valves smooth in 0-3 of the oral, and O'l 5 of the aboral part, strongly
dentated in the remaining 0'55 middle part ; teeth conical, of nearly equal size. In the half frontal
perimeter of the shell (along one border of each valve) forty to forty-five pores, in the half sagittal
fifty-four to fifty-six pores, in the half equator thirty-two to thirty-six pores. Each pore is
surrounded by a hexagonal frame, and pierces the shell in an oblique direction, dilated in the middle
part (figs. 5, 6). Shell very thick-walled, several longitudinal crests on both sides of the keel of
each valve. Hinge very strong, usually with a broad ligament between the two unequal aboral lips
of the hinge.

Dimensions. — Length of the shell 0-8, height 0'6, breadth 0'4.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

Genus 726. Conchoceras,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C oncharida with dentate lateral margins and a sharp sagittal
keel of the compressed valves, and with two caudal horns on the hinge (a dorsal and a
ventral).

The genus Conchoceras has the same lenticular keeled and .laterally compressed
shell as the preceding ancestral genus Conchopsis, but is distinguished from it by the
development of two large caudal horns on the aboral hinge. It bears therefore the
same relation to the latter as Conchidium does to Conchellium.

1. Conchoceras caudatum, n. sp. (PL 124, fig. 15).

Shell lenticular, slightly compressed ; proportion of the longitudinal diameter to the sagittal
and lateral = 6:5:4; sagittal and cinctural perimeter ovate, frontal perimeter elliptical. Free

1 Conchoceras = Mussel with horns ; xo'yxi> xe'oaj.

1728 THE VOYAGE OF H.M.S. CHALLENGER.

margins of the two boat-shaped valves dentate nearly in the whole perimeter ; in one lateral border
of each valve eleven or twelve very large conical teeth, the largest of which are nearly half as
high as the valve. On the aboral hinge of the shell two divergent, very large horns, four-sided
pyramidal, acute, straight, at the base perforated by a few large pores. The dorsal horn (of the
smaller valve) is somewhat shorter than the ventral horn (of the larger valve). The apical distance
of both horns is somewhat greater than their length, and about half the length of the shell. In
the half frontal perimeter (along one border of each valve) thirty-two to thirty-four pores, in the
half sagittal perimeter thirty-four to thirty-eight, in the half equator thirty to thirty-three. The
pores are smaller near the girdle-fissure, irregularly quadrangular, and arranged in longitudinal
rows, which are separated by meridional crests, and converge towards both poles of the main axis.

Dimensions. — Length of the shell (without the horns) 0-24 to 0'26, height 0'20 to O22, breadth
016 to 018 ; length of the horns 01 to 013.

Habitat. — Eastern part of the Tropical Atlantic, near the Equator, Station 348, depth 2450
fathoms.

2. Conchoceras cornutum, n. sp. (PL 124, fig. 16).

Shell lenticular, strongly compressed on both sides ; proportion of the longitudinal axis to
the sagittal and lateral = 4:3:2. Sagittal perimeter ovate, frontal perimeter elliptical, cinctural
perimeter spindle-shaped. Free margins of the two keeled valves in the oral third smooth, in the
remaining part strongly dentate ; ten or eleven large teeth on one lateral border of each valve, the
largest about half as high as the valve. On the aboral hinge of the shell two fenestrated apophyses
which bear two stout, strongly curved horns, like pincers ; the dorsal horn (of the smaller upper
valve) is shorter and less curved than the ventral horn (of the larger lower valve). The lips of
the mouth (at left on fig. 16) are also unequal, the upper lip eniarginate. In the half frontal
perimeter of the valve twenty-two to twenty-four pores, in the half sagittal perimeter twenty-eight
to thirty, in the half equator twenty to twenty-two. The pores are separated by high parallel
crests and arranged in longitudinal rows, which converge towards the aboral hinge.

Dimensions. — Length of the shell (without the horns) 0'36 to 0'4, height 0'27 to 0'3, breadth
0-2 to 0-22 ; length of the horns 016 to 0'22.

Habitat. — Tropical Atlantic, Station 338, depth 1990 fathoms.

Family LXXXI V. C<ELODENDRIDA, Haeckel (PL 121).

Goelodendrida, Haeckel, 1862, Monogr. d. RadioL, p. 360.

Definition. — PH^EODARIA with a bivalved lattice-shell, composed of two hemi-
spherical valves, a dorsal and a ventral. A conical cupola or a pyramidal galea arises
from the apical pole of both valves, therefore at the opposite poles of the sagittal axis.
Rhinocanna and frenula wanting. Three or more hollow radial tubes arise from each
valve and are symmetrically disposed. Sometimes their branches form an outer

REPORT ON THE RADIOLARIA. 1729

bivalved mantle. The central capsule is so enclosed between the two inner valves,
that its three openings lie in the open frontal fissure between them.

The family Ccelodendrida differs from the preceding Concharida (its probable
ancestral group) in the development of a conical galea or pyramidal cupola on the
apical pole of each valve, and of three or more hollow radial tubes arising from each
galea. They do not possess, however, the peculiar sagittal nasal tube or rhinocanna,
which is constantly developed from the base of .each cupola (and connected with its
apex by a frenulum) in the following family, the Ccelographida. These latter differ
also from the former in the constant possession of prominent verticillate styles.

The family Ccelodendrida was founded in 1862 in my Monograph (p. 360) and
represented hitherto only by two species of the genus Ccelodendrum, there described
(p. 361, Taf. xiii. figs. 1-3, and Taf. xxxii. fig. 1). This first description, however,
contained some errors, which were afterwards (in 1879) corrected by Richard Hertwig ;
this author also gave the first accurate description of the central capsule and its three
openings. In the rich collection of the Challenger, the Coalodendrida are represented
by four genera, but only seventeen species, some of which, however, are cosmopolitan
and very common, particularly Ccelodendrum.

The two valves of the lattice-shell, dorsal and ventral, are either hemispherical, or
somewhat more flatly vaulted or cap-shaped. They are never connected in the equatorial
zone of the body, as I supposed in my Monograph (1862, loc. cit.] ; but they are separated
by the girdle-fissure, a free circular equatorial interval, in which lie the three openings
of the enclosed central capsule. Though the two valves, therefore, have no direct
connection, they are, however, always opposed so accurately, that their equal free
circular edges correspond exactly one to the other, so that the apex of each valve lies in
one pole of the sagittal axis. From this apex there arises on each valve an irregular
conical or three-sided pyramidal cupola, the galea (PI. 121, figs. 3, 4, 8). The
Coelodendrida differ in the possession of this galea from the Concharida, and agree with
the Ccelographida ; but they never exhibit the peculiar rhinocanna or nasal tube, which
arises from each galea in the latter family.

The siliceous lattice-plate of the two valves, and of the galea arising from them, is
very thin and fragile, and its irregular roundish pores are extremely variable in size,
number, and disposition. Sometimes the pores are so small and so scarce, that the plate
appears nearly solid. At other times the siliceous plate seems to be really solid, and
covered by a network of thin crests, the small dimples between which give to it the appear-
ance of being fenestrated. Often the pores or the dimples are wanting in the central part
of each valve, while they are very numerous and dense in the peripheral part. The same
may be said of the lattice-plate of the galea, which is sometimes nearly solid, at other
times richly fenestrated. The Coelodendrida agree in this structure with the following

(ZOOL. CHALL. EXP. — PAET XL. — 1886.) Er 217

1730 THE VOYAGE OF H.M.S. CHALLENGER.

family, the Coelographida, and differ from the preceding family, the Concharida, in
which the siliceous wall of the two valves is much thicker, and perforated by regular
circular or roundish pores.

The galea or conical cupola in the apex of the two valves (" der kegelformige
Aufsatz " of the German authors) has in all Ccelodendrida a triangular base and an
irregularly conical or nearly three-sided pyramidal form. Its cavity is about one-third
or one-fourth as large in diameter as the cavity of the hemispherical valve upon which
it rests. The galea is relatively smaller and more irregularly formed than in the
Ccelographida, and differs essentially from that of the latter in the constant absence of
a rhinocanna ; there are also wanting, therefore, the characteristic frenula, which
connect the nasal tube with the apex of the galea. The cavity of the galea probably
always communicates with that of the valves by pores in the separating siliceous plate,
and is besides pierced by irregular pores in its outer wall, very variable in form, size,
and number, but it does not communicate with the cavity of the hollow radial tubes,
from which it is separated by a thin, solid, siliceous plate.

The hollow radial tubes which arise from the galea in the Ccelodendrida do not
seem to possess that constant regularity in number, origin, and disposition, which
is found in the following family, and there serves for distinction of genera. In my
first description of the CcBlodendrida (1862, loc. cit., p. 362), I pointed out this
irregularity, and mentioned that the number of radial tubes arising from each galea
varies from three to eight ; the total number therefore amounts to from six to
sixteen, the same minimum and maximum numbers which we shall encounter also in the
radial styles of the following family. But whilst it is easy to determine the position
and relation of these hollow tubes in the Ccelographida, owing to the constant sagittal
position of their rhinocanna, this task is very difficult in the Coelodendrida, where the
rhinocanna is wanting. In the most frequent cases there arise from each galea three or
four tubes, more rarely five or six, and very rarely seven or eight. The simplest and
probably the original case is the development of three tubes, two of which are paired
(divergent on the right and left), while the third is odd, lying in the sagittal plane.
Perhaps these three primary tubes may be compared to the three cortinar feet of the
NASSELLAKJA, so that we may regard the two paired anterior as pectoral, and the odd
posterior as a caudal tube. Usually the two paired or pectoral tubes arise from two
corners of the triangular base of the galea, whilst the third odd or caudal tube does not
arise from the third corner of the base, but more or less above it, and often even from
the highest point or the apex of the galea. In the majority of species observed, this
odd sagittal tube is forked even at its origin, so that two divergent tubes (an anterior
and a posterior) arise from the apex of the galea (PL 121, figs. 3, 8). More rarely
the two paired or pectoral tubes are also forked at the base, so that three pairs of tubes
arise from each galea, and the total number of tubes amounts to twelve. Very rarely

REPORT ON THE RADIOLARIA. 1731

/

four separate tubes or four pairs of tubes arise from each galea, viz., two from the two
anterior corners of the basal triangle, one from the posterior corner, and one from the
apex of the galea. It is possible that this difference in the origin, furcation, and number
of the hollow radial tubes may be employed for the distinction of genera of Coaloden-
drida, in the same manner as it is employed in the next following family, the
Coelographida. But I have not been able, in spite of numerous and accurate examina-
tions, to demonstrate in the former the same regularity in number and arrangement
of the tubes as in the latter. It seems that these relations here are very variable, even
in one and the same species, and not yet fixed.

It is, however, probable, on the other hand, that the primary tubes (all or partly)
are identical in the Ccelodendrida and Coelographida. This is most probably the case
with the posterior odd or caudal tube, which seems to be never wanting, and in both
families is developed in the form of a dichotomous brush (never in the form of a verticillate
style). Possibly also the two paired pectoral tubes are homologous in both families.

The hollow tubes are perfectly simple and unbranched only in one genus,
Ccelodoras, which is probably the common ancestral form of both families, and
which may have been derived from Concharium by development of a galea and tubes
on the sagittal apex of the valves. All the other Coelodendrida have branched spines,
and the ramification is constantly dichotomous, or repeatedly forked. There never
occur in this family those characteristic " styles," or verticillate prolonged tubes, which
we find in all Ccelographida. Usually the cylindrical tubes are slightly curved and
forked even near their base. The furcation is repeated a variable number of times in the
different species. In the largest species each tube becomes a brush with more than one
hundred terminal bristles.

We divide the Coelodendrida into two subfamilies, according to the different
development of the distal branches of the hollow tubes. In the Coelodorida all the
branches of the tubes remain free and are never connected by anastomoses, so that the
surface of the bivalved skeleton is protected by the free radial distal branches of the
tubes. In the larger species of Ccelodendrum (e.g., Ccelodendrum furcatissimum,
PL 121, fig. 1), the numerous branches of the dichotomous tubes form a dense thicket,
similar to that in the Coelotholida.

In the second subfamily, Coelodrymida, the distal branches of the tubes are
connected by numerous anastomoses, and compose either a simple lattice-plate on the
surface of the skeleton (Ccelodrymus), or a thicker envelope of spongy framework
(Caslodasea). The lattice-mantle so produced is always bivalved, and its two outer
hemispherical valves (dorsal and ventral) correspond exactly to the two inner
valves, from which arise the hollow tubes. The free margins of the two external
mantle-valves come externally into contact in the equatorial plane of the body, in which
the girdle-fissure lies internally between the two central shell-valves. The free edges

1732 THE VOYAGE OF H.M.S. CHALLENGER.

of the two external mantle-valves, opposed to one another in the circle of the equator,
seem usually to catch one into another in the same way as the corresponding man tie -
valves of the Coeloplegmida are loosely connected (PI. 128, figs. 1, 7). A true con-
crescence between the two valves seems never to take place.

The two subfamilies of Ccelodendrida therefore exactly correspond to the two sub-
families of the following family, the Coelographida. The Ccelodorida and Coelotholida
form in a similar way a thicket, by dichotomous ramification of the hollow tubes, all the
branches of which remain free. The Coelodrymida and Coeloplegmida, on the other hand,
form an outer lattice-mantle by anastomosing branches. The latter two subfamilies, of
course, have been derived correspondingly from the two former, and the common ancestral
form of all four is probably Ccelodoras, derived from the Concharida.

Though the two corresponding subfamilies in both groups are very similar, they are,
however, separated by important hereditary characters. All Ccelodendrida (the Ccelodorida.
without a mantle as well as the Ccelodrymida with a mantle) possess no rhinocanna and
no frenula on the galea, and they never develop prominent verticillate styles ; the
surface of their calymma is probably always spherical or subspherical. All Ccelographida,
however (the Ccelotholida without a mantle as well as the Cceloplegmida with a mantle),
possess a rhinocanna and frenula on the galea, and always develop prominent verticillate
styles ; the surface of their calymma is probably alwaj^s symmetrically polyhedral.

The superficial armature of the skeleton in the Coelodendrida is rather simple, and by
no means so manifold and differentiated as in the more highly developed Coelographida.
The thin terminal branches of the hollow tubes are in the Coelodorida closed at the distal
end, and armed with a variable number of short teeth (PI. 121, fig. 2), or with a spinulate
terminal knob, or a corona of recurved hooks (ibid., figs. 5-7). In the Coelodrymida,
however, where the distal ends of the branches by anastomosing form the lattice-
mantle, the spherical surface of this latter is armed with numerous thin spathilla3 or
radial bristles (often zig-zag or spinulate), and each bristle usually bears at the distal
end a small anchor with two, three, or four recurved teeth ; the outer convex edge of
these teeth is usually smooth, the inner concave edge denticulate. All these ramules and
branches of the tubes (also the thinnest terminal threads) are hollow, and filled up by

Jell7-

The central capsule of the Ccelodendrida does not lie outside the two central valves (as I

supposed in my first description, in 1862, being deceived by the dark enveloping phseodium,
Monogr. d. Eadiol., Taf. xxxii. fig. 1), but it is enclosed between the two valves, as in the
preceding and the following family. The first accurate description of it was given by
Eichard Hertwig in 1879 (loc. cit., p. 95, Taf. x. fig. 3). Its constant position between
the two lattice- valves (dorsal and ventral) is such, that its three openings lie in the frontal
plane, in the open fissure between the valves. The astropyle or the main-opening, with the
radiate operculum and the tubular proboscis arising from it, lies on the anterior (or oral)

REPORT ON THE RADIOLARIA. 1733

pole of the main axis, whilst the two lateral accessory openings, or parapylee, lie on both
sides of the posterior (or aboral) pole, to the right and left. The position of the capsule
is therefore the same as in the preceding Concharida (Pis. 123-125), and the following
Ccelographida (Pis. 126-128). The large nucleus, enclosed in the central capsule, is
usually half as broad, and contains numerous nucleoli.

The calymma, or the extracapsular jelly- veil, is in the Ccelodendrida usually spherical,
very voluminous, and includes the entire skeleton, the thicket of the Crelodorida as
well as the lattice-mantle of the Ccelodrymida. Only the outermost terminal branches
of the tubes in the former, and the radial bristles and spathillse on the surface of the
latter, remain free and project beyond the surface of the calymma. The phseodium is
usually very large, three to four times as broad as the central capsule, and envelops it
often completely. Usually it envelops only the anterior half of it, and the proboscis
(PI. 121, figs. 1, 9). Often numerous green, brown, or blackish phaeodellse are scattered
through the whole calymma, and sometimes accumulate in a superficial layer on its
surface. The galea of both valves is usually also filled up by the phseodium.

Synopsis of the Genera of Ccelodendrida.

I. Subfamily

Ccelodorida.

Hollow tubes, arising from the
galea of both valves, simple or
dichotomously branched ; the
branches always free, not anas-
tomosing. No outer lattice-
mantle.

II. Subfamily

Coelodrymida.

Hollow tubes, arising from the
galea of both valves, dichoto- -
mously branched; the branches
anastomose and form an outer
bivalved lattice-mantle.

Tubes simple, not branched, . . .727. Ccelodaras.

Tubes forked or dichotomously branched, . . 728. Cadodendrum.

Lattice-mantle simple; its meshes lying in a spherical

surface, ...... 729. Caslodrymus.

Lattice-mantle spongy; its meshes lying in different

planes, ...... 730. Ccelodasea.

Subfamily 1. CCELODORIDA, Haeckel.

Definition. — C oelodendrida without an external bivalved lattice-mantle, with
simple or branched hollow tubes, the terminal branches of which are free, not anastomosing.

Genus 727. Ccelodoras,1 n. gen.

Definition. — (Jrelodendrida without external lattice-mantle, with simple, not
branched, radial tubes, which arise separately from the galea.

1 Ccelodoras— Hollow spear; xoiXo?, o&'jaf.

1734 THE VOYAGE OF H.M.S. CHALLENGER.

The genus Ccelodoras is the simplest form of the Ccelodendrida, and may be regarded
as the common ancestral form of this and of the following family. It differs from all other
members of these two families in the simple shape of the hollow radial tubes which arise
from the galea, and are neither branched nor forked ; the galea is very small, a flat
triangular cap. Ccelodoras may be derived immediately from Concharium or Con-
chonia (p. 1723), by development of the galea and the radial tubes.

1. Ccelodoras hexagraphis, n. sp.

Three straight, cylindrical, equidistant hollow tubes arise divergent from the three corners of
each galea, and are about as long as the diameter of the valves, at the distal end armed with a
spinulate knob. The odd sagittal (or caudal tube) is directed backwards, the two paired (or pectoral)
tubes, forwards.

Dimensions. — Diameter of the valves 0'16, length of the tubes 0'2.

Habitat. — Central Pacific, Station 266, depth 2750 fathoms.

2. Ccelodoras octographis, n. sp.

Four hollow cylindrical tubes, slightly curved, arise divergent from each galea, and are about
one and a half times as long as the diameter of the valves, at the distal end knob-shaped, and
armed with four crossed, recurved teeth. Two anterior (or pectoral) tubes arise from the two
frontal corners of the galea basis, and diverge forwards to right and left. Two posterior tubes (a
sagittal and a caudal) arise from the posterior corner of each galea, and diverge in the sagittal plane
backwards.

Dimensions. — Diameter of the valves 0'2, length of the tubes 0'3.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

Genus 728. Ccelodendrum,1 Haeckel, 1860, Monatsber. d. k. preuss. Akad.

d. Wiss. Berlin, p. 801.

Definition. — Coe lo dendr ida without external lattice-mantle, with branched
radial tubes, the hollow branches of which are free and never connected by anastomoses.

The genus Ccelodendrum is the first described form not only of the family
Coelodendrida, but of all P h ae o c o n c h i a or bivalved PH^ODAEIA ; it is also the most
common form of this group, and represented by ten different species, some of which are
cosmopolitan, very common, and widely distributed. In my first description of
Ccelodendrum I confounded it erroneously with some forms of Ccelodasea and Ccelo-
graphis, the separated fragments of which I had found entangled between the branches
of the former. The first figures of Ccelodendrum are given in my Monograph, in 1862,

1 Ccelodendrum = Hollow tree ; xoiAoj, Stio*.

REPORT ON THE RADIOLARIA. 1735

Taf. xiii. figs. 1-3 (not 4) and Taf. xxxii. fig. 1 (not 2 and 3). Ccelodendrum has
been derived from Coelodoras by furcation and repeated dichotomous ramification of
the hollow radial tubes which arise from the galea.

Subgenus 1. Ccelodendridium, Haeckel.

Definition. — Eamification of the hollow tubes regularly dichotomous, each branch
being forked again; therefore the two terminal ramules of the last branches equal.

1. Ccelodendrum ramosissimum, Haeckel.

Ccelodendrum ramosissimum, Haeckel, 1862, Monogr. d. Radiol., p. 363, Taf. xiii. figs. 1-3.
Ccelodendrum ramosissimum, R. Hertwig, 1879, Organism, d. Radiol., p. 93, Taf. x. figs. 3, 12.

Terminal branches regularly forked, with two equal, smooth, nearly straight or slightly curved
fork-branches, diverging at right angles ; their end-knobs with four crossed (or sometimes five or
six) short recurved teeth.

Dimensions. — Diameter of the spherical skeleton 1*2 to 1*8 of the two central valves 0'2 to 0'25.

Habitat. — Cosmopolitan ; Mediterranean, Atlantic, Indian, Pacific ; many Stations, surface and
at various depths.

2. Ccelodendrum spinosissimum, n. sp. (PL 121, fig. 7).

Terminal branches regularly forked, with two equal, smooth, straight, fork-branches, diverging
at right angles, their end-knobs echinoidal, subspherical or club-shaped, with numerous short radial
thorns.

Dimensions. — Diameter of the skeleton 2 to 2-2 of the two central valves 0'25 to 0'03.

Habitat. — Tropical Atlantic, Stations 346 to 349, surface.

3. Ccelodendrum fur catissimum, n. sp. (PI. 121, fig. 1-4).

Terminal branches regularly forked, with two equal, smooth, straight, or slightly curved fork-
branches, diverging at acute angles ; their end-knobs very small, with three short, diverging, conical
teeth.

Dimensions. — Diameter of the skeleton 2 to 2'5, of the two central valves 0'3 to 0'4.

Habitat. — Cosmopolitan ; Atlantic, Indian, Pacific; many Stations, surface, and at various depths.

4. Ccelodendrum bifurcum, n. sp.

Terminal branches regularly forked, with two equal, smooth, more or less curved fork-branches,
diverging at acute angles ; their end-knobs thin, with two slender, parallel, bristle-shaped teeth.
Dimensions. — Diameter of the skeleton 0'6 to 0'8, of the two central valves 01 to 015.
Habitat.— North Pacific, Stations 252 to 256, surface.

1736 THE VOYAGE OF H.M.S. CHALLENGER.

5. Coelodendrum gracillimum, Haeckel.

Coelodendrum gracillimum, Haeckel, 1862, Monogr. d. RadioL, p. 364, pi. xxxii. fig. 1.

Terminal branches regularly forked, with two equal, spinulate, curved fork-branches, diverging
at obtuse angles and covered with numerous small thorns ; their end-knobs cap-shaped, with a
corona of six to eight small recurved teeth. In one specimen of this species (in 1859) I found
entangled the fragments of Ccelographis gracillima, figured in Taf. xxxii. figs. 2, 3, loc. cit. I supposed
at that time, erroneously, that the latter belonged to full-grown specimens of the former.

Dimensions. — Diameter of the skeleton 1 to 1'2, of the valves 0'15 to 0'2.

Habitat. — Mediterranean (Messina), surface.

6. Coelodendrum lappaceum, n. sp.

Terminal branches regularly forked, with two equal, spinulate, straight or slightly curved fork-
branches, diverging at acute angles and covered with small recurved hooks ; their end-knobs large,
conical, with a prominent apex and a basal corona of six to eight recurved teeth.

Dimensions. — Diameter of the skeleton 1-5 to 1'8, of the valves 0'22.

Habitat. — South Pacific, Stations 285 to 295, depth 1500 to 2600 fathoms.

Subgenus 2. Ccelodendronium, Haeckel.

Definition. — Ramification of the hollow tubes more or less irregular, mainly in the
periphery; the terminal ramules of the last branches unequal.

7. Coelodendrum cervicorne, n. sp. (PL 121, fig. 8).

Terminal branches irregularly ramified, with unequal, smooth, curved ramules, diverging at
obtuse angles, their end-knobs echinoidal, small, with short, diverging, conical thorns.
Dimensions. — Diameter of the skeleton 1 to T2, of the valves 0'2.
Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

8. Ccelodendrum digitatum, n. sp.

Terminal branches irregularly ramified, with unequal, spinulate, straight ramules, diverging at
acute angles ; the two last fork-branches digitate, each with five diverging finger-shaped ramules,
lying in a meridian plane ; their end-knobs conical, pointed, with a corona of recurved hooks.

Dimensions. — Diameter of the skeleton 1*6, of the valves 0'24.

Habitat. — Indian Ocean, Madagascar (Rabbe) surface.

REPORT ON THE RADIOLARIA. 1737

9. Ccelodendrum flabellatum, n. sp. (PI. 121, fig. 6).

Terminal branches flabellate, irregularly ramified, each of the last two fork-branches being
divided into four or five diverging straight branches of different lengths ; usually the last eight or
ten ramules lie in a meridional plane ; their end-knobs cap-shaped, with a corona of recurved teeth.

Dimensions. — Diameter of the skeleton 2'0 to 2'5, of the valves 0'25 to 0'3.

Habitat. — North Pacific, Station 235 to 240, surface.

10. Ccelodendrum serratum, n. sp. (PI. 121, fig. 5).

Terminal branches flabellate, irregularly ramified like the preceding species ; it differs from this
in the strong compression of the broad, saw-shaped, terminal branches ; the two opposite edges
(placed in the meridional plane of the flabellum) are finely serrated ; their end-knobs with a corona
of diverging teeth.

Dimensions. — Diameter of the skeleton 3'0 to 3'2, of the valves 0'3 to 0'36.

Habitat. — Central Pacific, Stations 270 to 274, depth 2350 to 2925 fathoms.

Subfamily 2. CCELODRYMIDA, Haeckel.

Definition. — C celodendrida with an external bivalved lattice-mantle, produced
by the anastomosing branches of the hollow radial tubes.

Genus 729. Ccelodrymus,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C oelodendrida with an external bivalved lattice-mantle, produced
by the anastomosing terminal branches of the hollow tubes, which are connected in a
spherical face.

The genus Ccelodrymus, and the following closely allied genus Ccelodasea, represent
together the small subfamily Coelodrymida, differing from the Ccelodorida in the
possession of an outer bivalved lattice-mantle. They exhibit therefore the same relation
to the latter, that in the following family the Cceloplegmida bear to the Ctelotholida.
The bivalved spherical mantle is composed of a simple lattice-plate in Ccelodrymus, of
a spongy framework in Ccelodasea ; the anastomosing branches of the hollow radial
tubes become connected in the former in a spherical face, in the latter in the form of a
spongy framework.

1 Caslodrymus = Forest of hollow trees, xoiAoj Sji/^etof.
(ZOOL. CHALL. BXP. — PART XL. — 1886.) Rr 218

1738 THE VOYAGE OF H.M.S. CHALLENGER.

1. Ccelodrymus ancoratus, n. sp. (PI. 121, figs. 9, 10).

Network of the mantle loose, with large, irregular, polygonal meshes ; the terminal branches of
the forked trees, which communicate at the spherical surface of the calymma, and compose the
mantle, are smooth. Spherical surface covered with very numerous and thin zigzag radial
filaments, which are about as long as the galea, and bear at the distal end an anchor with two
recurved teeth, denticulate at the concave proximal edge (fig. 10).

Dimensions. — Diameter of the spherical lattice-mantle 2 to 2'5, of the valves O3 to 0'4
Habitat. — South-Eastern Pacific (off Juan Fernandez), Station 300, depth 1375 fathoms.

2. Ccelodrymus lappulatus, n. sp.

Network of the mantle rather dense, with numerous and small irregular polygonal meshes ; the
terminal branches of the forked trees, which compose the mantle, are spinulate. Spherical surface
densely studded with very numerous spinulate, radial filaments, which are about half as long as the
galea, and bear at the distal end an anchor with four crossed recurved teeth, denticulate at the
concave proximal edge.

Dimensions. — Diameter of the spherical lattice-mantle 2'5 to 3, of the valves 0'4 to 0'5.

Habitat. — South-Western Pacific (east of New Zealand), Station 169, depth 700 fathoms.

3. Ccelodrymus echinatus, n. sp.

Network of the mantle very dense, with very numerous and small irregular roundish meshes ;
the terminal branches of the forked trees, which compose the mantle, are spiny. Spherical surface
studded with very numerous, thin, radial bristles, which bear no anchor at the distal end.

Dimensions. — Diameter of the spherical lattice-mantle 1'8, of the valves 0'22.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

Genus 730. Ccelodasea,1 n. gen.

Definition. — Ccelodendrida with an external spongy lattice-mantle, produced by
the anastomosing branches of the hollow tubes, which are connected in different heights.

The genus Ccelodasea differs from the preceding Ccelodrymus in the spongy structure
of the outer bivalved mantle. The hollow branches of the radial tubes of Ccelodendrum,
which anastomose in Ccelodrymus only on the spherical surface of the calymma, and form
a simple lattice-sphere, become connected in Ccelodasea in different planes (laterally and
terminally), and therefore form an irregular spongy framework. The latter exhibits
therefore to the former a relation similar to that which Spongoplegma bears to Carpo-
sphcera among the Sphseroidea.

1 Ccelodasea = Hollow thicket, xoiAoj laata.

REPORT ON THE RADIOLARIA. 1739

1. Ccelodasea ramosissima, Haeckel.

Ccelodendrum ramosissimum (partim), Haeckel, 1862, Monogr. d. Radio!., p. 363, Taf. xiii. fig. 4.

Spongy framework of the spherical bivalved mantle very dense and thick, produced by very
numerous, irregular anastomoses of the lateral and terminal branches, which arise from the hollow
tubes. The last and thinnest terminal branches are forked, as seen in the radial section of fig. 4
(loc. tit.), their ends are closed and armed with some very small denticles (not open, as figured in
fig. 4). In my Monograph I had confounded this species with Ccelodendrum ramosissimum, which
however, may possibly be its ancestral form.

Dimensions. — Diameter of the spongy spherical mantle 2 to 2'5, of the central valves 0'15.

Habitat — Mediterranean (Messina), surface.

2. Ccelodasea spongiosa, n. sp.

Spongy framework of the bivalved mantle rather loose, not nearly so thick and dense as in the
preceding species. The last and thinnest terminal branches are prolonged into denticulate, zig-
zagged, radial filaments, which bear at their distal end an anchor with two recurved teeth (similar
to Ccelodrymus ancoratus, PI. 121, figs. 9, 10).

Dimensions. — Diameter of the spongy spherical mantle 3 to 3'2, of the central valves 0'24.

Habitat. — Equatorial Atlantic, Station 347, depth 2250 fathoms.

Family LXXXV. COSLOGRAPHIDA, n. fam. (Pis. 122, 126-128).

Definition. — PH^EODARIA with a bivalved lattice-shell, composed of two hemispherical
valves, a dorsal and a ventral. A conical cupola or a helmet-shaped galea arises on the
apical pole of each valve, therefore on the opposite poles of the sagittal axis. The cavity
of the galea communicates with the sagittal rhinocanna, a peculiar nasal tube, which rests
upon the valve, and is connected with the galea by a simple or double frenulum ; its
opening being directed towards the proboscis. Three or more branched hollow radial
tubes arise from each valve, and are symmetrically disposed. Sometimes their branches
form an outer bivalved mantle. The central capsule is so enclosed between the two
inner valves, that its three openings lie in the open frontal fissure between them.

The family Ccelographida, the last family of the PILEODAKIA, exhibits the highest
degree of morphological development, not only in this group, but among all Radiolaria.
They attain also the greatest size of all members of the class, since the diameter of their
body is sometimes more than 20 mm., and in a few species even more than 30 mm.
The complexity of their structure attains at the same time such a high degree, that
they may be regarded as the most complicated, and (in a morphological sense) as the most
highly developed of all Protozoa. Nevertheless their body always remains a single cell,

1740 THE VOYAGE OF H.M.S. CHALLENGER.

and is closely allied to the preceding Ccelodendrida ; they differ from the latter mainly
in the development of a peculiar new organ, the " rhinocanna," or " nasal tube." This is
a hollow tube placed in the sagittal plane, arising from the base of each galea, and is con-
nected with its apex by a simple or double frenulum. Between the oral openings of the
two opposed rhinocannse (one dorsal and one ventral) lies the proboscis of the central
capsule.

The first observed species of Ccelographida was Ccdographis gracillima, some parts of
which (but not the entire skeleton) were figured in my Monograph (1862, Taf. xxxii.
figs. 2, 3). But I confounded these with Ccelodendrum gracillimum, in the branched
hollow trees of which the fragments of the former were entangled. I detected this error
afterwards, when I had the opportunity of observing some complete specimens. The first
description of a complete skeleton was given in 1882 by 0. Biltschli, who examined a
large specimen of Ccelothamnus davidoffii, captured by Davidoff in the Mediterranean
(Zeitschr. £ wiss. Zool., Bd. xxxvi. p. 486, Taf. xxxi.). In the rich collection of the
Challenger I was able to distinguish not less than nine genera and twenty-six species of
Ccelographida, but the majority of their large and most fragile skeletons were more or
less injured, or quite broken. It was, therefore, of the highest importance for the
minute study of this difficult group, that Dr. John Murray, during his expedition to the
Fsero'e Channel (in 1882, in H.M.S. "Triton"), discovered in the Gulf Stream the
beautiful Cceloplegma murrayanum, and brought up home hundreds of well-preserved
specimens (PI. 127). Only by the complete examination of this excellent material it
was possible to answer many difficult questions as to their morphology, and to correct
the errors in my description and in that of Biitschli.

We divide the family Ccelographida into two rather different subfamilies, which
may afterwards be separated as two divergent families, the Coelotholida (PL 122) and
Cosloplegmida (Pis. 126-128). Both groups may be easily distinguished at a glance,
since the numerous branches, arising from the hollow radial tubes, remain constantly
free and independent in the former, and represent a spiny thicket, whilst in the
latter they constantly become united, and by anastomosing form a peculiar " mantle,"
or outer envelope of delicate network. But besides, there are other and more important
differences between the two groups. The peculiar hollow tube, arising from the base of
the galea on each valve, which is filled with phseodella, and which we call the rhinocanna,
develops in the Ccelotholida on its open mouth two paired lateral frenula (right and
left), which connect it (like two lateral bridges) with the base of two paired hollow
main tubes (the " frontal tubes "). In the Coelospathida, however, the mouth of the
rhinocanna develops a single odd frenulum only (in the sagittal plane), and is connected
by it with the base of an odd, single, hollow main tube, directed forwards, the " nasal
style."

The central bivalve lattice-shell, from which the galea and the tubes arise, exhibits in

EEPORT ON THE EADIOLAETA. 1741

the Ccelographida essentially the same form and structure as in the preceding Coeloden-
drida. The only (but important) difference between them is indicated by the constant
presence of the peculiar rhinocanna in the former, whilst this is always absent in the
latter. The two valves of the shell, dorsal and ventral, are either hemispherical or some-
what flatter, sometimes nearly cap-shaped, and formed of an extremely delicate and irregu-
larly fenestrated plate of silica, as in the Ccelodendrida. As in the latter, so also in the
Coelographida both valves are of similar form and usually of equal size, but sometimes
the dorsal is a little smaller than the ventral valve. The remarkable difference which
Biitschli describes in his Ccelothamnus davidoffii, and the inverse origin of the three tubes
in both valves (loc. cit., Taf. xxxi. figs. 2, 4), depends upon an error of observation,
produced by the artificial inversion of one valve, and the dislocation of their natural
arrangement. The valves are never in direct contact, but separated by the equatorial
fissure or girdle-cleft, in which the girdle zone of the enclosed central capsule and its
three openings lie freely (PI. 127, figs. 4, 5; PI. 128, fig. 2). The free margins of
both valves, which are opposite to one another, and bound the girdle-cleft, are always
equidistant, so that the cleft in the whole equatorial circumference is of equal breadth.
The margins are usually irregularly denticulate, sometimes armed with longer bristles
(PI. 127, fig. 8), more rarely smooth (fig. 5). The delicate lattice-work of the valves
is always irregular and very variable, usually with numerous small and unequal pores,
sometimes rudimentary, so that the valves appear partly solid and hyaline. The size
of the valves is usually between 0'2 and 0'5 (in diameter).

The galea (g) or the apical cupola, which arises from the vaulted apex of each valve (or
its sagittal pole) is more developed in the Coelographida than in the preceding Coeloden-
drida, and differs from the latter in the peculiar rhinocanna arising from its base, and in
the single or double frenulum, connecting the open mouth of the rhinocanna with the
odd or paired main tube arising from the galea. The two opposite galese lie therefore
on the poles of the sagittal axis of the bivalve shell, and are so symmetrically disposed
in the sagittal plane, that the open mouths of their rhinocannse are directed towards the
oral pole of the main axis, and nearly come in contact with the proboscis arising from
the radiate operculum of the central capsule (PI. 127, figs. 4, 5).

The size and form of the galea are very variable, even in one and the same species.
The volume of its cavity is generally about as great as that of the hemispherical valve
from which it arises, sometimes larger, at other times smaller. Its fundamental form is
constantly dipleuric or bilateral, since the radial hollow tubes arise symmetrically on both
its sides, and the rhinocanna proceeding from its base determines the sagittal plane.
Usually the galea has the form of a vaulted helmet, the convex crest of which is inclined
towards the mouth (PI. 127, figs. 4, 5, 8, 9). Its anterior or apical part is broad and
truncated in the Coslotholida, more or less conical in the Coelospathida ; sometimes it
assumes .nearly the form of a bilateral three-sided pyramid, at other times it is more

1742 THE VOYAGE OF H.M.S. CHALLENGER.

pear-shaped (Pis. 126-128). The thin siliceous wall of the galea has the same
irregular and delicate network as the valve from which it arises, and sometimes the
small irregular pores are also here reduced, so that the wall becomes partly solid. In
some cases the thin, solid, siliceous plate of the galea and of the valve is covered by an
irregular delicate network of crests ; the dimples between these crests may be easily
confounded with true pores.

The cavity of the galea is filled with phseodella and does not communicate with the
cavity of the shell- valves, nor with the cavity of the radial tubes filled by jelly ; it is closed
towards the latter and the former by a thin solid plate of silex. Biitschli (1882, loc. cit.,
p. 488) describes in Ccelothamnus a large circular opening (Taf. xxxi. figs. 2a, 4a), and
states that this is a direct communication between the cavities of the valves and of
their galeas which are called by him " der dreiseitige kastenformige Aufsatz " (e). This
error was caused by the fact that he observed the valves from the apical face only.
The apparent opening of communication does not exist, and is the optical section of the
rhinocanna, the shortened walls of which he describes as " trapezformige Kiesellamelle "
(7) ; the two lateral edges of the latter (" die seitlichen Zipfel," 8) are the paired frenula,
which connect the open mouth of the rhinocanna with the base of the two frontal tubes.

The "rhinocanna or nasal tube" (PI. 126, figs. 1, 4 ; PI. 127, figs. 4-9«) is a very
remarkable organ which is common to all Coelographida (without any exception), and
distinguishes them markedly from .all the other Radiolaria, and particularly from the
closely allied Ccelodendrida, in which we find no trace of it. The rhinocanna is a
cylindrical or three-sided prismatic hollow tube, which lies in the sagittal plane, on the
outer surface of each valve, arises from the base of the galea, and is directed towards the
proboscis of the central capsule. The two opposite rhinocannse open on each side of the
latter (PL 127, figs. 4-9m), and usually this "nasal mouth" or the anterior opening of
the nose is somewhat dilated or even funnel-shaped. The posterior opening of the nose
passes directly over into the base of the cavity of the galea.

Usually the rhinocanna is densely filled up by dark phseodella, which enter by this
channel into the cavity of the galea (PL 127, figs. 4, 5, 9). Sometimes the entire
phaeodium is enclosed in the two galeae and their rhinocannse (figs. 5,9), whilst at other
times a great part of the phseodium lies outside of their cavities, and surrounds the pro-
boscis of the mouth, or even the anterior half of the central capsule (fig. 4). The length of
the cylindrical rhinocanna is usually about equal to that of the galea, whilst the diameter
of the latter is from three to five times as great as that of the former. The structure
of the thin wall is the same in both. The fine reticulation (fig. 8) is produced either by
true, very small and irregular pores, or by a fine network placed on the solid thin wall.
We may distinguish on each rhinocanna an outer or distal convex face, which is opposite
to the proximal concave face of the galea, and an inner concave or proximal face, which
rests immediately upon the convex outer face of the shell-valve ; a thin solid lamella of

REPORT ON THE RADIOLARIA. 1743

silica here completely separates the cavities of the valve and of the rhinocanna resting
upon it.

The "frenula or nasal suspensoria" (PL 127, figs. 4-96) are thin ligaments of silica,
which connect the nasal mouth (m) with the base of the main tubes arising from the galea;
they are, therefore, also common to all Ccelographida, and an exclusive and marked
attribute of this family. They are, however, different in the two subfamilies of this
group, corresponding to the different origin of the odd or paired main tubes. In the
Coeloplegmida (Pis. 126-128) from the apex of each galea arises an odd main style, the
nasal style (g 1), and its base is connected with the nasal mouth by an odd frenulum (6).
In the Ccelotholida however (PI. 122) the large nasal odd style is always wanting, and
there arise two paired frontal tubes from the two corners of the truncate frontal face of
the galea ; therefore two paired frenula are developed (a right and a left), and these,,
converging towards the nasal mouth, connect its distal corner with the base of the two
frontal tubes.

The odd frenulum of each valve of the Cceloplegmida lies therefore in the sagittal1
plane, whilst the two paired frenula of the Ccelotholida lie on both sides of it, to the right
and left. The frenula seem to be supporting columellse or pillars, which support the
fragile skeleton, and mainly effect a fixed prop for the fragile galea. In the Coelotholida
the frenula are often rather broad and irregularly fenestrated lamellae of silica (PL 122,
fig. 2), whilst in the Cceloplegmida they are usually thin ligaments, fenestrated only at
the broadened ends, which are inserted inside on the distal apex of the nasal mouth,
and outside on the base of the nasal main styles.

The large hollow tubes which arise from the galea of all Ccelographida, are very
variable in number, size and shape, but are always richly branched and symmetrically
arranged in the dorsal and the ventral valve of the shell. They exhibit an important
difference in the two subfamilies of the group ; in the Coalotholida all the branches, and also
the thin terminal ramules, are free, without any junction ; in the Coeloplegmida, however,
they communicate by frequent anastomoses, and the connected terminal ramules form on
the surface of the calymma an outer lattice-mantle of very delicate network. Another
marked difference between the two families is indicated by the origin and site of those
main tubes which are connected with the rhinocanna by a frenulum. In the Ccelo-
plegmida an odd, very large main tube (the nasal style) arises from the anterior apex of
each galea and bears on its base an odd frenulum. This nasal style and its frenulum is
altogether wanting in the Coelotholida, where two paired main tubes (the frontal tubes)
arise from the lateral corners of the truncate anterior side of the galea, and are connected
with the mouth of the rhinocanna by two paired convergent lateral frenula.

We distinguish in all Ccelographida two different forms of hollow branched tubes,
which we will call " brushes " and " styles." The brushes are dichotomously branched
from the base, not verticillate ; their distal ramules remain separate in the Ccelotholida

1744 THE VOYAGE OF H.M.S. CHALLENGER.

•

and compose the spiny surface of the peculiar "fork-thicket;" whilst in the Ccelo-
graphida they become connected by frequent anastomoses and form the outer " lattice-
mantle." The styles, however, are much longer, projecting over the surface of the
thicket or the mantle, and are not dichotomously branched, but verticillate, or armed
with cruciate or alternately cruciate pairs of branches ; the larger branches of the styles
may be again dichotomously branched, like the brushes ; whilst the free prominent parts
of the styles are always verticillate or cruciate-pinnate. The brushes are identical with
the hollow tubes of the Coelodendrida, whilst the styles are peculiar forms of apophyses,
wanting in the latter.

The minimum number of hollow tubes which arise from each valve is three, and these
are probably homologous with the three primary tubes of the Coeloclendrida. Two of
these are paired (right and left), whilst the third is odd and lies in the sagittal plane ;
they have the same position as in the tripodal NASSELLARIA, and may therefore bear the
same names, the two paired anterior or pectoral tubes being divergent forwards, the odd
or caudal tube being directed backwards (so in the Ccelotholida, PI. 121). The odd
caudal tube (probably identical with the odd tube of the Ccelodendrida) is always a
brush, dichotomously branched, and never prolonged into a free style. The two paired
frontal or pectoral tubes, however, are usually prolonged into two long verticillate styles.
The basal origin also of these three primary tubes is different. The two pectoral or
anterior paired tubes always arise from the galea itself, whilst the posterior odd or
caudal tube usually arises behind the galea from the valve (PI. 127, figs. 4-8, g 6).

Since these three primary tubes, the odd caudal and the paired pectoral, are probably
homologous in all Ccelographida and Coalodendrida, they have a great morphological
importance, similar to the three primary feet of the NASSELLABIA. All other tubes arising
from the valves must be regarded as secondary apophyses, since they are not constant
in all members of the two families, but present only in some of them. All the Coalotho-
lida observed (a small number of species only) possess no secondary tubes, but only the
three primary ; whilst all Coeloplegmida possess one or more secondary tubes, and one of
these is constant, viz., the odd nasal style, directed towards the mouth, and arising as
the foremost from the apex of the galea (PL 127, figs. 4-8, g 1).

The maximum number of tubes observed, which arise from each valve in the Coloepleg-
mida, is eleven ; five of these are odd and placed in the sagittal plane of the body, viz. :—
(A) the primary caudal tube (PI. 127, figs. 4-8, g G); (B) an odd procaudal tube, arising
between the caudal and the sagittal tube ; (C) the sagittal tube, placed either in the
sagittal axis of the body or near it (often prolonged into a sagittal style, PL 128,
%• !); P) an odd postnasal tube, arising between the sagittal and the nasal tube; (E)
the odd nasal tube, constant in all Coeloplegmida, and connected at its base by the odd
frenulum with the rhinocanna (PL 127, figs. 4-8, g I). All other tubes occurring in
the Cceloplegmida are paired, and symmetrically arranged on both sides of the sagittal

REPORT ON THE RADIOLARIA. 1745

plane, at right and left ; their maximum number is three pairs, viz. : — (F) the paired
pectoral tubes (as the foremost), directed forwards ; (G) the paired frontal or lateral
tubes, placed either in the frontal axis of the valve, or in a neighbouring axis, directed
towards the right and left pole (PI. 127, figs. 4-8, g 4 and g 5); (H) the paired tergal
tubes, directed backwards (constant in all Cceloplegmida). The origin of these tubes is
rather variable, since they arise in nearly allied species, sometimes independently of one
another, at other times united at the base. But a closer comparison of them in the
different species will demonstrate their homology, caused by constant heredity.

The terminal ramules of the brushes, which form the subspherical "fork-thicket" in
the Ccelotholida, the outer " lattice-mantle " in the Cceloplegmida, are constantly armed
at the distal ends either with spathillse or with anchor-pencils, bunches of those most
elegant spinulate threads, which bear at the free end an anchor, or a whorl of two, three,
or four recurved teeth (PL 122, fig. 8 ; PL 127, fig. 10; PL 128, figs. 1, 6). The
pencils are usually dichotomously branched, their threads zig-zag or delicately serrate,
often armed with very small recurved denticles, and the anchor teeth (commonly three
or four) are usually smooth on the convex outer, serrate on the concave inner edge. The
entire surface of the subspherical thicket in the Coelotholida, and of the polyhedral lattice-
mantle in the Coeloplegmida, is armed with thousands of those most elegant spathillae, or
anchor-pencils.

The " fork-thicket " of the Coelotholida is identical with that of the Coelodendrida, and
is composed only of the innumerable dichotomous branches of the hollow tubes. It envelops
the two central valves and the enclosed central capsule in the same way as in the Coelo-
dendrida. But the Ccelotholida differ from these latter in constantly possessing a
rhinocanna and two frenulae. The entire form of this thicket, which in the few species
observed was never complete, but always more or less destroyed, is usually probably
subspherical or polyhedral, sometimes cordate or kidney-shaped. Its surface is densely
studded with thousands of spathilla3. Its diameter is about four to eight times as great
as that of the enclosed bivalve shell.

The " lattice-mantle " of the Coeloplegmida, which replaces in this subfamily the fork-
thicket of the Cffilotholida, is always produced by the anastomoses of the distal ramules
of the brushes, and of those branches of the styles which do not proceed over the surface
of the mantle. Its network is always very irregular, and composed of polygonal meshes of
very different sizes. Usually it is quite simple, and may be compared with the cortical
shell of the Disphserida. More rarely it is more or less spongy. Its surface is densely
studded with thousands of spathillse or anchor-pencils. The entire form of the lattice-
mantle is always symmetrically polyhedral, since its dorsal and ventral halves are
symmetrically developed on both sides of the equatorial plane, and therefore correspond
perfectly to the enclosed smaller halves of the central bivalve shell. The two valves of
the lattice-mantle (dorsal and ventral valves) are never really united and grown together,

(ZOOL. CHALL. EXP. PART XL. 1886.) Kf 219

174(5 THE VOYAGE OF H.M.S. CHALLENGER.

but are in loose contact in the equatorial plane ; here the free edges of both valves catch into
one another by means of free ramules (PL 128, figs. 1, 7). This loose connection is
similar to what occurs in the Conchopsida (or in the Concharida with dentate edges), but
never so regular. The special form of the polyhedral lattice-mantle depends on the
number, arrangement, and development of the styles, which proceed over its surface ; it
preserves the polyhedral form of the calymma, on the surface of which it is deposed.

The characteristic styles of the Ccelographida (which are never found in the preceding
Ccelodendrida) are longer hollow tubes, symmetrically disposed on both valves. They
are prominent over the surface of the fork-thicket in the Coelotholida, of the lattice-mantle
in the Coaloplegmida. They bear in these latter a peculiar terminal coronet on their distal
end, whilst in the former this end is armed with large pencils of spathillse. The styles
may be forked once or twice at their base, but in their greatest part they are verticillate,
and not dichotomously branched like the brushes. The lateral branches of the styles
are usually very numerous and regularly cruciate in alternating opposite pairs. In the
odd nasal style, e.g., the first and third pairs of opposite lateral branches usually lie in
the frontal plane, the second and fourth in the sagittal plane, perpendicular to the former,
and so on. A similar regular disposition of the lateral branches is found also in
other styles, but not in all. There are certain styles in which the lateral branches are
not opposite in pairs, but alternate or verticillate, and others in which they represent
unequal branches of forks, so that each single segment of the branched style represents
the stouter branch of a fork, and the appertaining lateral branch the thinner branch of
the fork. Further accurate examinations are required to recognise the different laws of
the ramification of the styles in the different forms of Coelographida. The lateral
branches of the styles are usually again dichotomously branched inside the lattice-mantle,
and their distal ends pass over into its network. But the verticillate or cruciate branches,
which arise from the free part of the styles outside the lattice-mantle, are always armed
with the same elegant pencils of spathillae which cover the surface of the fork-thicket in
the Ccelotholida, the surface of the lattice-mantle in the Creloplegmida. These pencils
also are often regularly opposite in pairs, and the pairs alternate in two planes perpen-
dicular one to another (PL 128, figs. 1, 4).

The terminal coronets are peculiar ornaments which protect the distal ends of the
styles in the Coeloplegmida, whilst in the Coelotholida these are armed with the usual
pencils of spathillae (PL 122, fig. 8). Each coronet is usually produced by the double,
triple, or quadruple furcation of the free distal end of the style ; therefore composed of
four, eight, or sixteen terminal branches, which, on account of their peculiar form and
function, we may call " fingers." More rarely the ramification of the coronets is more or
less irregular, and sometimes the number of the fingers exceeds twenty or even thirty.

In the majority of species eight fingers are regularly disposed (PL 127, figs. 1-3 ;
PL 128, figs. 1-8). Often too sixteen occur, rarely four only. Sometimes the fingers

REPORT ON THE RADIOLARIA. 1747

are placed nearly in one plane and form a hand. The form of the fingers is very variable
and most characteristic of the individual species. Very often they have the shape of a
human finger, and are smooth, spinulate, or armed with recurved hooks. The distal end
of each finger often again bears a small coronet or a spathilla (PL 128, figs. 5-9), and
sometimes it is arrow-shaped (PL 126, fig. 2a). All these apophyses of the terminal
coronets as well as the anchor-pencils of the mantle and the finest branches of the
tubes, are hollow and filled up by jelly.

The different number and arrangement of. the styles offers the best means for the
distinction of genera in the Ccelographida. The minimum number is six (Ccelogr aphis,
PL 126, fig. 1), the maximum number sixteen (Ccelothamnus, PL 122, fig, 3, and Ccela-
galma, PL 126, fig. 4). Since the arrangement of the styles in both valves is
constantly symmetrical, the fundamental form of the whole body is in all Cceloplegmida
" amphithect," as in the Ctenophora. The longitudinal or main axis of the body is
vertical, with two distinct poles ; the proboscis of the central capsule and the two
rhinocannse are directed upwards, to wards 'the oral pole ; the caudal tube of each valve is
directed downwards, towards the aboral pole. The two other axes of the body are
unequal, horizontal, and perpendicular one to the other ; each has two equal poles. On
the poles of the sagittal axis lie the galese of the dorsal and ventral valves ; on the poles
of the frontal axis lie the two secondary openings or parapylae of the central capsule.
The frontal fissure or the large cleft between the dorsal and ventral valves of the skeleton
lies in the vertical frontal plane of the body, which is perpendicular to the vertical sagittal
plane; the equatorial plane, however, is horizontal.

The central capsule of the Ccelographida exhibits the same shape and position as in the
preceding Ccelodendrida. It is subspherical, slightly depressed in the direction of the
main axis, and lies enclosed between the two central valves of the lattice-shell. Its three
constant openings lie in the frontal plane, and therefore in the frontal fissure between
the two valves. The astropyle, or the main-opening of the capsule, lies on the oral pole of
the main axis, and its radiate operculum (d) is directed upwards ; the curved proboscis
arising from it (o) is prominent between the mouths of the two opposed rhinocannse.
The two lateral parapylse or accessory openings lie on both sides of the aboral pole, on
the right and left (PL 127, figs. 4-6). The large spheroidal or somewhat lenticular
nucleus (n) is usually about half as broad as the capsule, and contains numerous nucleoli.
The protoplasm around the nucleus contains many vacuoles, and in the oral part of the
capsule (between nucleus and operculum) often numerous groups of crystals (PL 127,
figs. 4-6&, 7). The double membrane of the central capsule exhibits the same shape as
in the other PH^EODAKIA.

The calymma, or the extracapsular jelly- veil, is in the Coelographida very voluminous,
and includes the entire skeleton, the fork-thicket of the Ccelotholida, the lattice-mantle
of the Cceloplegmida, and also the prominent large styles. Only the distal ends of the

1748

THE VOYAGE OF H.M.S. CHALLENGEE.

latter (with the terminal coronets), and the anchor pencils, covering the surface of the
thicket and the mantle, seem to project over the surface of the calymma. The entire
form of the latter is therefore a symmetrical polyhedron. The phseodium fills up a small
part only of the calymma, and is usually enclosed in the two galese and their rhino-
cannse (PI. 127, figs. 5, 9), but often also a part of the phseodium is scattered
around the oral half of the central capsule.

Synopsis of the Genera of Ccelographida.

I. Subfamily

Coelotholida.

Rhiuocanna of each valve with
two paired lateral frenula.
The distal ends of the <
dichotomous brushes are
not united by anastomoses,
and form an outer bi-
valved fork-thicket.

Eight paired styles (four on each valve),
Twelve paired styles (six on each valve),
Sixteen paired styles (eight on each valve),

II. Subfamily

Cceloplegmida.

Rhinocanna of each valve with
an odd sagittal frenulum.
The distal ends of the
dichotomous brushes are
united by anastomoses, and
form an outer bivalved
lattice-mantle.

One odd and two paired styles
on each valve,

Mantle with six styles. •!

AT j-i -J.-U • vi * i ( Two odd and two paired

Mantle with eight styles. < , , 1,1

( styles on each valve,

•»«• 11 MI . f One odd and four paired

Mantle with ten styles. < . , hi

IT ii -L-LL ^ i i f Two odd and four paired
Mantlewithtwelvestyles. *

fourteen

Mantle with
styles.

Mantle with
styles.

sixteen

One odd and six paired styles
on each valve,

Two odd and six paired styles
on each valve,

731. Ccelotliolus.

732. Ccelothauma.

733. Ccelothamnus.

734. CcBlograpliis.

735. Ccelospatliis.

736. Caelodecas.

737. Ccdostylm.

738. Ccdoplegma.

739. Ccelagalma.

Subfamily 1. CCELOTHOLIDA, Haeckel.

Definition. — Ccelographida with two paired lateral frenula on each galea, and
with free terminal branches on the hollow radial tubes, without an external lattice-
mantle. Eight to sixteen long styles are prominent over the surface of the fork-thicket,
which is composed of the caudal brush and the dichotomous basal branches of the styles.

Genus 731. Ccdotholus,1 n. gen.

Definition. — C celographida with two paired lateral frenula on each galea,
without external lattice-mantle, armed with eight styles (two pairs of styles on each
valve).

1 C<xloiholus= Hollow cupola; xoiAo?, tfo'xoj.

REPORT ON THE RADIOLARIA. 1749

The genus Ccelotholus and the two following genera form together the subfamily
Ccelotholida, the hollow tubes of which do not communicate by anastomosing branches,
and therefore form no lattice-mantle, as in the following subfamily Cceloplegmida.
Another important difference between these two subfamilies of Ccelographida is found
in the arrangement of the main tubes and their connection with the rhinocanna. In all
Coelotholida a pair of divergent frontal styles arise from the truncate oral side of each
galea, and are connected with the mouth of the rhinocanna by two lateral convergent
paired frenula (right and left) ; whereas the characteristic odd nasal style, which in all
Coelaplegmida arises from the sagittal apex of each galea and is connected with the
mouth of the rhinocanna by an odd sagittal frenulum, is always wanting. The total
number of long verticillate styles, which project over the outer surface of the fork-thicket,
is eight in Ccelotholus, whilst it is twelve in Ccelotliauma, and sixteen in Ccelothamnus.
The two latter may be derived from Ccelotholus, as the common ancestral genus of this
subfamily.

1. Ccelotholus octonus, n. sp. (PL 122, figs. 1, 2).

Eight styles of equal length, regularly zig-zag, twice as long (in their free part) as the
diameter of the loose fork-thicket. Anchor-pencils gradually tapering from the proximal towards
the distal end. Each of the four primary frontal tubes (to the right and left of each valve) is
simply forked, and the pectoral (anterior) branch of each tube is so diametrically opposed to the
tergal (posterior) tube of the other side, that they form together a double cross.

Dimensions. — Diameter of the whole body 12, of the fork-thicket 2'5.

Habitat — South-Eastern Pacific, Station 300, depth 1375 fathoms.

2. Ccelotholus cruciatus, n. sp.

Eight styles of equal length, straight, twice as long (in their free part) as the diameter of the
dense fork-thicket. Anchor-pencils of about equal size throughout their whole length. Each of
four primary frontal tubes is divided into two equal, widely divergent branches ; the anterior
branches of the right side are diametrically opposed to the posterior branches of the left side, so that
all eight together form a double cross.

Dimensions. — Diameter of the whole body 20, of the fork-thicket 4'0.

Habitat. — South-Western Pacific (off Sydney), Station 164A, depth 1200 fathoms.

3. Ccelotholus ancoratus, n. sp.

Eight styles of different lengths, slightly curved. Anchor-pencils gradually tapering from the
proximal to the distal end. Each of the four primary frontal tubes is divided into two divergent

1750 THE VOYAGE OF H.M.S. CHALLENGER.

branches of different lengths ; the anterior (or pectoral branch) twice as long (in the free part) as
the diameter of the fork-thicket, the posterior (or tergal branch) three times as long.

Dimensions. — Diameter of the whole body 20, of the fork-thicket 3'2.

Habitat. — Indian Ocean (Sunda Strait), Eabbe, surface.

Genus 732. Ccelothauma,1 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C celographida with two paired lateral frenula on each galea, with-
out external lattice-mantle, armed with twelve styles (three pairs of styles on each
valve).

The genus Ccelothauma differs from the preceding Codotholus, its ancestral form, in
the possession of twelve long, prominent styles, six of which are opposite in three pairs
on each valve. In the single species observed each of the four main tubes (opposite in
pairs on the frontal corners of the two galese) is simply forked, as in Ccelotholus; but
whilst in this latter all eight styles remain simple, in Ccelothauma the anterior (or
pectoral) branch only is simple, the posterior (or tergal) branch is again forked.

1. Ccelothauma duodenum, n. sp. (PI. 122, figs. 3-5).

Twelve styles straight, of different lengths. Two short bilateral main tubes arise opposite in
pairs from the two frontal corners of each galea, and are divided into an anterior and posterior
branch. The anterior or pectoral branch is simple, and twice as long as the diameter of the
fork-thicket. The posterior or tergal branch is again forked near the base, and its two divergent
branches are three times as long as the diameter of the fork-thicket. All twelve styles are densely
studded with anchor-pencils of nearly equal size.

Dimensions. — Diameter of the whole body 21, of the fork thicket 3'5.

Habitat. — South-Western Pacific (east of New Zealand), Station 169, depth 700 fathoms.

Genus 733. Caslothamnus,2 Haeckel, 1879, Sitzungsb. med.-nat. Gesellsch.

Jena, Dec. 12, p. 6.

Definition. — C celographida with two paired lateral frenula on each galea,
without external lattice -mantle, armed with sixteen styles (four pairs of styles on
each valve).

The genus Ccclothamnus differs from its ancestral form, Ccelotholus, in the duplication
of the number of long verticillate styles, which are prominent over the surface of the

1 Ccelothauma = Hollow wonder; xo/Ao;, tfai^a. ^ Ccelothamn-us = Hollow thicket; xoiXoj, &«.pm',.

REPORT ON THE RADIOLARIA. 1751

dense fork-thicket. Whilst in Ccelotholus each frontal main tube (arising from the
frontal corner of the galea at right and left) is divided into an anterior or pectoral, and
a posterior or tergal style, in Ccelothamnus each of these two divergent main styles is
again forked, so that the total number of projecting and radially diverging styles amounts
to sixteen. One Mediterranean species of this genus. Ccelothamnus davidqffii, has been
already described by Biitschli in 1882 (Zeitschr. f. wiss. Zool., vol. xxxvi. p. 486,
Taf. xxxi.). Though its description on the whole is accurate, some important errors,
which may be here corrected, are to be met with. The two central valves of the lattice-
shell (dorsal and ventral) are symmetrically equal in size and in form, as in all other
Coelographida ; the different forms and the inverse arrangement of the two valves,
described by Biitschli (pp. 488, 491), were effected by an artificial dislocation and
inversion. The peculiar opening a, which, according to his opinion, was supposed to
bring about a direct communication between the cavities of the galea and its valve, is in
reality the optical section of the rhinocanna, the two convergent frenula of which (y) he
figured, but did not recognise. Ccelothamnus attains the greatest size among all
Radiolaria ; the diameter of the body in Ccelothamnus maximus amounts to 33 mm.

1. Ccelothamnus bivalvis, n. sp. (PI. 122, figs. 6—9).

Sixteen styles all of equal length, about three times as long (in their free part) as the diameter
of the dense fork -thicket. The size of the anchor-pencils tapers from the proximal to the distal
end. Each of the four primary frontal tubes (which arise in opposite pairs from the frontal corners
of the two gale;e) is twice forked, and so produces four styles.

Dimensions. — Diameter of the whole body 18, of the fork -thicket 2-4 to 3'0.

Habitat. — North Atlantic, Canary Islands, Station 354, surface.

2. Ccelothamnus davidoffii, Biitschli.

Cailothamnus davidoffii, Biitschli, 1882, Zeitschr. f. wiss, Zool., vol. xxxvi. p. 486, Taf. xxxi.

Sixteen styles all of equal length (?), about four times as long (in their free part) as the
diameter of the fork-thicket. The size of the anchor-pencils is nearly equal throughout their
entire length. (Compare the careful description of this species by Biitschli,)

Dimensions. — Diameter of the whole body 15, of the fork-thicket l-8.

Habitat. — Mediterranean (Villafranea, near Nice), Davidoff,. surface,

3. Ccelothamnus sedecimalis, n. sp.

Sixteen styles straight, of different sizes. The pectoral or anterior branch of each frontal main
tube is simple, and twice as long as the diameter of the large fork-thicket. The tergal or posterior
branch is forked at the base, and its anterior branch is again forked in the middle part, so that three

1752 THE VOYAGE OF H.M.8. CHALLENGER.

long divergent styles arise from each tergal tube. The hindermost of these is the longest, three
times as long as the diameter of the fork-thicket. All anchor-pencils have nearly equal size.

Dimensions. — Diameter of the whole body 22, of the fork-thicket 5'2.

Habitat. — South Pacific, Station 166 (west of New Zealand), depth 275 fathoms.

4. Ccelothamnus maximus, n. sp.

Sixteen styles straight, of different sizes. The four frontal main tubes are already forked at
the base, so that from each frontal corner of the two galeae two divergent tubes, an anterior or
pectoral and a posterior or tergal, arise. Each of these is again forked, and each branch prolonged
into a very long verticillate style. The hindermost style of each side is the longest, twice as long
as the foremost, and one and a half times as long as the two intermediate styles. The size of the
anchor-pencils decreases in the distal third of the styles.

Dimensions. — Diameter of the whole body 32, of the fork-thicket 7 '5.

Habitat. — Central Pacific, Station 271, depth 2425 fathoms.

Subfamily 2. CCELOPLEGMIDA, Haeckel.

Definition. — C eel o graph id a with an odd sagittal frenulum on each galea, and
with an external bivalved lattice-mantle, produced by the anastomosing branches of the
hollow radial tubes. Six to sixteen long styles are prominent over the surface of the
mantle, and bear terminal coronets.

Genus 734. Coelographis,1 n. gen.

Definition. — C celographida with an odd sagittal frenulum on each galea and
an outer lattice-mantle, armed with six styles (one odd and two paired styles on each
valve).

The genus Coelographis is the simplest form of the Cceloplegmida, or of those
Coelographida in which the branches of the arborescent tubes are united on the surface
of the calymma, and form a delicate bivalved lattice-mantle. In all these Cceloplegmida
an odd nasal main style is developed on the apex of the galea, and this is connected by
an odd sagittal frenulum with the mouth of the rhinocanna. Coelographis differs from
the other Coelographida in the minimum number of coronal styles, viz., three on each
valve, an odd anterior (nasal) and two paired posterior (tergal).

1. Coelographis regina, n. sp. (PI. 126, figs. la-Id).

Shell-mantle twice as* long as broad, its frontal perimeter isosceles triangular, with a triangular
excision at the base, its sagittal perimeter slenderly ovate. Nasal odd style twice as long as the

1 Ccelographis = Hollow style ; xoiXo?,

REPORT ON THE RADIOLARIA. 1753

paired tergal styles, the former with ten to twelve, the latter with five to six alternate-cruciate pairs
of lateral branches. Terminal coronets (on the free distal ends of the styles) palmate, with ten to
twelve spinulate, irregular, finger-shaped branches (fig. Id).

Dimensions. — Length of the shell 5 "5, breadth 2'7.

Habitat. — South-Eastern Pacific (off Juan Fernandez), Station 297, depth 1775 fathoms.

2. Ccelographis sagittella, n. sp.

Shell-mantle one and a half times as long as broad, its frontal perimeter arrow-shaped, isosceles
triangular, with a deep concave excision at the base, its sagittal perimeter slenderly ovate. Nasal odd
style one and a half times as long as the paired tergal styles, the former with fourteen to sixteen,
the latter with eight to nine verticils of branches. Terminal coronets three times forked, with eight
subregular, broad and spinulate, finger-shaped branches.

Dimensions. — Length of the shell 6'4, breadth 4'2.

Habitat.— Central Pacific, Station 271, depth 2425 fathoms.

3. Ccelographis hexastyla, n. sp.

Shell-mantle one and a half times as long as broad, very similar to the preceding species, its
frontal perimeter isosceles triangular, with a flat basal excision. Nasal odd style one and a third
times as long as the paired tergal styles, the former with fourteen to sixteen, the latter with ten to
twelve verticils of branches. Terminal coronets with four forks in the form of a cross, and eight
divergent spinulate fingers.

Dimensions. — Length of the shell 4'2, breadth 3'1.

Habitat. — North Pacific, Station 259, depth 2225 fathoms.

4. Ccelographis gracillima, Haeckel.

Ccelodendrum gracillimurn (partim) Haeckel, 1862, Monogr. d. Radiol., Taf. xxxii. figs. 2, 3.

Shell-mantle one and a third times as long as broad, similar to the three preceding species,
its frontal perimeter isosceles triangular. Nasal odd style one and a half times as long as the two
paired tergal styles, the former with eleven or twelve, the latter with seven or eight pairs of
branches. Terminal coronets irregularly dichotomously branched, with twelve to sixteen spinulate
fingers. The network of the mantle is also spinulate (loc. cit., fig. 3). This species was formerly
confounded by me with Ccelodendrum gracillimum (loc. cit., fig. 1), since I found a fragment only of
the former entangled in the branch-work of the latter (1859, in Messina). Afterwards (in 1877)
I observed a complete specimen in Corfu.

Dimensions. — Length of the shell 3'2, breadth 24.

Habitat. — Mediterranean (Messina, Corfu), surface.

5. Ccelographis triangulum, n. sp.

Shell-mantle about as long as broad, its frontal perimeter equilateral triangular, without basal
excision, with three equal straight sides. Nasal odd style and the two paired pectoral styles nearly

(ZOOL. CHALL. EXP. — PAET XL. — 1886.) Rr 220

1754 THE VOYAGE OF H.M.S. CHALLENGEK.

of equal length, each with ten to twelve alternate-cruciate pairs of lateral branches. Terminal
coronets umbrella-shaped, composed of eight equal, simply forked branches.

Dimensions. — Length of the shell 3'6, breadth 3'4.

Habitat. — South Pacific, Station 293, depth 2025 fathoms.

Genus 735. Ccelospathis,1 n. gen.

Definition. — C oalographida with an odd sagittal frenulum on each galea aud
an outer lattice-mantle, armed with eight styles (two odd and two paired styles on each
valve).

The genus Ccelospathis differs from the preceding Ccelographis in the possession of
four coronal styles on each valve. Two of these are odd and lie in the sagittal plane,
viz., the constant vertical nasal style (directed towards the mouth), and the horizontal
sagittal style, which is placed in the equatorial plane, in the sagittal axis of the body.
The two other styles are paired and identical with the tergal styles of Ccelographis,
directed backwards, and divergent to right and left.

1. Ccelospathis ancorata, n. sp. (PI. 128, figs. 1—7).

Shell-mantle one and a half times as long as broad, its frontal perimeter isosceles triangular ;
its zonal perimeter square, its sagittal perimeter nearly rectangular, with a concave excision on the
oral side (fig. 1). Odd nasal styles of both valves divergent in the sagittal plane (each with fourteen
to sixteen pairs of branches), three times as long as the odd sagittal styles (each with three or four
pairs) and twice as long as the paired tergal styles (each with four to six pairs of branches).
Terminal coronets (on the free distal end of the styles) three times forked, each with eight slender,
widely divergent fingers, which are curved, zig-zag, and armed with alternating recurved hooks ;
at the end of each finger a verticil of four to six small recurved teeth (fig. 5).

Dimensions. — Length of the shell 2 to 3, breadth 1'2 to 2-l.

Habitat. — South Pacific, Station 289, depth 2550 fathoms.

2. Ccelospathis octostyla, n. sp. (PL 128, fig. 8).

Shell-mantle one and a third times as long as broad, very similar to the preceding species ; but
differing from this in the following characters : the odd nasal styles bear ten to twelve pairs of
branches, and are twice as long as the odd sagittal and the paired pectoral styles, which are nearly
equal in size (each with five or six pairs of branches). The eight fingers of the terminal coronets are
less divergent and curved than in the preceding species, and each finger bears at its end a verticil
of four to six divergent, slender teeth, which are not recurved (fig. 8).

Dimensions. — Length of the shell 2'2 to 2'6, breadth 1'7 to 19.

Habitat. — Central Pacific, Stations 271 to 274, depth 2350 to 2750 fathoms.

1 Ccelospathis = Hollow whorl; x«iAof,

REPORT ON THE RADIOLARIA. 1755

3. Ccelospathis octodactyla, n. sp. (PI. 128, fig. 9).

Shell-mantle about as long as broad, in the frontal perimeter nearly isosceles triangular, very
similar to the two preceding species ; it differs from them in the following characters : all eight
styles have nearly equal size, and each bears six to eight pairs of branches. The eight fingers of
the terminal coronets diverge nearly in one plane, and are not curved in a zigzag manner, but armed
with alternate, slender, recurved hooks, which are larger than in the two preceding species, and
geniculate at the base ; the distal end of each finger bears a verticil of eight to ten very small
divergent teeth, which are not recurved (fig. 9).

Dimensions. — Length of the shell 24, breadth 2'2.

Habitat. — North Pacific, Station 252, surface.

Genus 736. Ccelodecas,^ n. gen.

Definition. — C celographida with an odd sagittal frenulum on each galea and
an outer lattice-mantle, armed with ten styles (one odd and four paired styles on each
valve).

The genus Ccelodecas is closely allied to Ccelographis, but differs from it in the
development of a new pair of styles on each valve. These are placed between the odd
nasal and the paired tergal styles, are usually directed laterally, parallel to the frontal
axis of the body, and may therefore be called frontal or lateral styles. The total
number of coronal styles is therefore ten.

1. Ccelodecas sagittaria, n. sp. (PI. 126, figs. 2a, 26).

Shell-mantle one and a half times as long as broad ; its frontal perimeter pentagonal, with a
deep median incision at the base ; the two oral sides of the pentagon twice as long as the two
lateral sides, and one and a half times as long as the base. Sagittal perimeter ovate ; equatorial
perimeter subcircular. Nasal odd style of each valve with fourteen to sixteen pairs of branches,
one and a half times as long as the paired frontal styles (each with eight to nine pairs), and twice
as long as the paired tergal styles (each with four to six pairs of branches). Terminal coronets (on
the free distal ends of the styles) richly branched, each with thirty to forty thorny fingers, which
bear a conical point with recurved teeth, like an arrow.

Dimensions. — Length of the shell 3'2, breadth 21.

Habitat. — Tropical Atlantic, Station 347, depth 2250 fathoms.

3. Ccelodecas decastyla, n. sp.

Shell-mantle one and a third times as long as broad ; its frontal perimeter pentagonal, with a
slight incision on the base ; the two oral sides of the pentagon as long as the base, and one and a

1 Ccelodecas = Shell with ten hollow styles; xo<Xo?,

1756 THE VOYAGE OF H.M.S. CHALLENGER.

half times as long as the two lateral sides. Nasal odd style of each valve with ten to twelve pairs
of branches, about twice as long as the four paired frontal and tergal styles, each of which bears
five or six pairs. Terminal coronets three times forked, each with eight straight, spinulate, slightly
divergent fingers, shaped like a human finger.

Dimensions. — Length of the shell 3'6, breadth 2'7.

Habitat. — Central Pacific, Station 272, depth 2600 fathoms.

3. Ccelodecas pentagona, n. sp.

Shell-mantle about as long as broad ; its frontal perimeter nearly regular pentagonal, with five
equal sides. Nasal odd style of each valve with six to eight pairs of branches scarcely longer than
the four paired frontal and tergal styles, each of which is provided with four to six pairs.
Terminal coronets irregularly branched, each with twelve to sixteen slender curved fingers, which
bear at the distal end a spinulate knob.

Dimensions. — Length of the shell 2 '6, breadth 2'4.

Habitat. — South Atlantic, Station 332, depth 2200 fathoms.

Genus 737. Ccelostylus,1 n. gen.

Definition. — C celographida with an odd sagittal frenulum on each galea and an
outer lattice-mantle, armed with twelve styles (two odd and four paired styles on each
valve).

The genus Ccelostylus is characterised by the possession of twelve coronal styles ; it is
closely allied to Ccelospathis, and differs from this in the development of a new pair of
styles on each valve. These are placed between the odd nasal and the odd sagittal style
of each valve, they are directed forwards, and may therefore be called " pectoral styles."

1. Ccelostylus bisenarius, n. sp. (PI. 126, fig. 3a, 36).

Shell-mantle one and a third times as long as broad ; its frontal perimeter pentagonal, with a
deep median incision at the base ; the two oral sides of the pentagon about as long as the basal
odd side, and half as long as the two lateral sides. Sagittal perimeter (fig. 3a) octagonal ; the
three paired lateral sides of the bilateral octagon about equal, and somewhat shorter than the
basal and oral odd sides. Equatorial perimeter rounded square. Nasal odd style of each valve
with twelve alternate-cruciate pairs of lateral branches, about twice as long as the two paired
pectoral styles (each with four pairs), and the odd sagittal style (with six pairs) ; the two paired
tergal styles bear eight pairs and are longer than the latter, shorter than the nasal style. All styles
are more or less curved, divergent, and at the distal end four tunes forked, bearing a terminal
coronet with sixteen spinulate fingers (fig. 36).

Dimensions. — Length of the shell 4'2, breadth 3'2.

Habitat. — Indian Ocean (Madagascar), Rabbe, surface.

1 Ccelostylus = Hollow style ; xoiXoj, irrfao;.

REPORT ON THE RADIOLARIA. 1757

2. Ccelostylus flabellatus, n. sp.

Shell-mantle one and a half times as long as broad, very similar to that of the preceding species.
It differs from this mainly in the peculiar form of the twenty-four terminal coronets, which are
flabellate and very similar to the terminal branches of Cazlodendrum fldbellatum (PI. 121, figs. 5, 6).
I formerly supposed, therefore, that both forms belonged to one and the same species. But though I
had no complete specimens of the two species, I was afterwards led to the opinion that one and
the same peculiar form of terminal branches is here produced by adaptation to similar conditions in
two very different genera. Each coronet is a flat flabellum, placed in a meridian plane, and
composed of eight pairs of spinulate branches as figured, loc. cit., in figs. 5 and 6. The cap-shaped
distal end of each finger is armed with eight to twelve recurved teeth.

Dimensions. — Length of the shell 3'8, breadth 2'6.

Habitat. — North Pacific, Station 252, surface.

Genus 738. Cceloplegma,1 n. gen.

Definition. — C oelographida with an odd frenulum on each galea and an
outer lattice -man tie, armed with fourteen styles (one odd and six paired styles on each
valve).

The genus Cceloplegma, distinguished by the possession of fourteen coronal styles,
is closely allied to Ccelodecas, but differs from it in the development of a new pair of
styles, on each valve. These are placed between the odd nasal and the paired frontal
styles, are directed forwards, and may therefore be called pectoral styles, corresponding
to those of Ccelostylus.

1. Cceloplegma murrayanum, n. sp. (PI. 127, fig. 1).

Shell-mantle about as long as broad, its frontal perimeter subcircular, or slightly pentagonal,
with five convex sides, its sagittal perimeter also nearly circular. Odd nasal style with six to eight,
the paired pectoral styles with two or three, lateral styles with three to five, and tergal styles
with six to nine pairs of branches. The central capsule constantly contains masses of crystals
(figs. 4-7). Terminal coronets (on the free distal ends of the styles) three times furcate, each
with eight simple and short fingers. This interesting species, discovered by Dr. John Murray
in August 1882, during the expedition of H.M.S. " Triton," in great numbers in the Gulf Stream,
off the Faeroe Channel, is very variable and connected by numerous transitional forms with the
following closely allied species. (Compare the following note.)

Dimensions. — Length of the shell T6 to 2'2, breadth 1'5 to 21.

Habitat. — North Atlantic, Gulf Stream, off the Fseroe Channel, in depths between 40 and 200

fathoms, John Murray.

1 Gceloplegma = Hollow framework ; xoiho;. T:~*.i

1758 THE VOYAGE OF H.M.S. CHALLENGER.

2. Cceloplegma tritonis, n. sp. (PL 127, figs. 2-13).

Shell-mantle one and a quarter times as long as broad, its frontal perimeter heptagonal, with
seven concave sides (fig. 2), its sagittal perimeter ovate, its zonal perimeter nearly square (fig. 3).
Odd nasal style with twelve to fourteen, the paired pectoral styles with three to four, lateral styles
with six to eight, and tergal styles with eight to ten pairs of branches. Coronets three times
forked, each with eight terminal branches, bearing a small spinulate knob. This remarkable
species, in external appearance very different from the preceding, is connected immediately with it
by numerous transitional varieties ; both species represent the opposite terminal poles of a long series
of " Darwinian metamorphic forms." If only the two specimens, figured in PL 127, figs. 1 and 2,
were known, every one would distinguish them as two widely different species. But the careful
comparison of numerous intermediate forms demonstrates that there is no " missing link " in this
long and remarkable chain. The careful comparative study of these very variable and most highly
developed Coelographida may be regarded as a strong argument for the theory of descent, and
explains the true " origin of species."

Dimensions. — Length of the shell 1'8 to 2-5, breadth T5 to 2*1.

Habitat. — North Atlantic, Gulf Stream, off the Fserb'e Channel, in depths between 40 and 200
fathoms, John Murray.

3. Cceloplegma tetradecastylum, n. sp.

Shell-mantle one and a third times as long as broad, its frontal perimeter heptagonal, with
seven concave sides. Similar to the preceding species, differs from it mainly in the prolonged nasal
style, which bears sixteen to eighteen pairs of branches, and is about three times as long as each of
the six paired styles, each of which bears five to six pairs of branches. Coronets three times forked,
each with eight terminal branches, armed with scattered spines, and bearing a knob with three
recurved hooks.

Dimensions. — Length of the shell 3'2, breadth 2-4.

Habitat. — Tropical Atlantic, Stations 335 to 342, surface.

4. Cceloplegma atlanticum, n. sp.

Shell-mantle one and a half times as long as broad, its frontal perimeter ovate. Similar to
Cceloplegma murrayanum (PL 127, fig. 1), differs from it in the different length of the styles ; the
nasal odd style (with eighteen to twenty pairs of branches) is about twice as long as the lateral
styles (with ten to twelve pairs), and three times as long as the pectoral and tergal styles (with six
to eight pairs). Coronets four times forked, each with sixteen terminal branches, armed with
recurved spines, and bearing a cross of four curved hooks.

Dimensions. — Length of the shell 2'5, breadth 1'7.

Habitat. — South Atlantic, Station 318, depth 2040 fathoms.

REPORT ON THE RADIOLARIA. 1759

Genus 739. Coelagalma,1 n. gen.

Definition. — C celographida with an odd sagittal frenulum on each galea and
an outer lattice-mantle, armed with sixteen styles (two odd and six paired styles on
each valve).

The genus Coelagalma represents the highest degree of development among the
Coslographida, and exhibits the maximum number of coronal styles in this family, viz.,
sixteen (eight on each valve). Two of these are odd (as in Ccelospathis and Ccelostylus),
viz., the longitudinal anterior nasal style, and the horizontal sagittal style. The six
others are paired (as in Cceloplegma), viz., two anterior or pectoral, two lateral or
frontal, and two posterior or tergal styles. Since Coelagalma in this highest developed
armature exceeds all the other Coeloplegmida, and exhibits at the same time the
utmost complexity in structural detail, it may be regarded as one of the most perfect
forms not among the PELEODARIA only, but among all Radiolaria.

1. Coelagalma mirabile, n. sp. (PI 126, figs. 4a, 46).

Shell-mantle one and a half times as long as broad, its frontal perimeter (fig. 4a) heptagonal,
with seven concave sides, its sagittal perimeter octagonal, its equatorial perimeter hexagonal (fig. 46),
the corners of the polygons are marked by the sixteen prominent styles. Nasal odd style longer;
and sagittal odd style shorter, than the six paired styles of each valve ; the two pectoral styles
are directed forwards, the two lateral styles are nearly opposed in the horizontal frontal diameter,
while the two shorter tergal styles are directed backwards. The terminal coronets (at the distal
ends of the sixteen styles) are four times forked, with sixteen equal spinulate fingers, each finger
at the distal end with eight recurved teeth. The entire surface of the bivalved latticed mantle is
densely studded with hundreds of most elegant anchor-pencils, so that the external appearance of
this beautiful species becomes one of the most wonderful among Radiolaria.

Dimensions. — Length of the shell 5'4, breadth 3'6.

Habitat. — Central area of the Pacific, Station 271, depth 2425 fathoms.

1 Calafjalma — Hollow ornament ;

1760 THE VOYAGE OF H.M.S. CHALLENGER,

NOTE ON THE DIMENSIONS AND MEASUEEMENTS OF THE DESCEIBED

SPECIES OF RADIOLARIA.

All the dimensions of the species of Radiolaria described in the present work are
given in millimetres. In the majority of the species the dimensions of only a single
observed specimen have been measured by the micrometer, and usually only the most
important proportions have been recorded. But since the outlines of nearly all the
species figured (with very few exceptions) have been drawn by the camera lucida,
and therefore usually are almost perfectly exact, and since the excellent artist, Mr.
Adolph Giltsch, has executed the lithographic plates with the greatest accuracy, having
examined the objects themselves under the microscope, it is very easy to determine
the dimensions of all the separate parts by comparative measurement. In very many
of the species described (perhaps nine hundred or a thousand) several specimens of
each species (usually three or four) have been measured comparatively, and the
dimensions recorded are taken as averages. A very important contribution to the
general conception of the proportions, and especially to the important question of the
constancy of the dimensions, has been given by my honoured friend, Dr. Reinhold
Teuscher of Jena. This excellent observer, to whom I am indebted for much and
important co-operation in my Radiolarian work, has instituted at my request a long
series of measurements, with the view of comparing the dimensions (of the entire
skeleton as well as of its individual parts) in numerous (usually twenty or thirty)
specimens of one and the same species. About three hundred species of very different
groups (mainly Sphseroidea, Diseoidea, Spyroidea, and Cyrtoidea) have
been measured in this manner, and the general survey of the results obtained (about
eight thousand measurements were recorded) has enabled me to form a good opinion of
the constancy and variability of the dimensions in the individual species. The general
result is, that they are not absolutely constant in any given case, but that each
species (of which many specimens have been carefully compared) exhibits a certain
degree of variability in all its proportions. The general meaning of " species,"
therefore, is in the unicellular Radiolaria the same as in all other organisms, and
its development follows the same laws as are so accurately explained by Charles
Darwin in his Origin of Species.

ADDENDA.

I. List of Tuvnty-tivo Deep-Sea, Radiolarians from the Banda Sea.

P. Hearting (L. N. 18) published in 1863 the description of 14 SPUMELLAKIA and
8 NASSELLAEIA, taken in depths between 900 and 4000 fathoms, in the Banda Sea. The
figures of them are, however, for the most part not complete enough. The names are the
following : —

L SPUMELLARTA.

1. Haliomma nitidum, figs. 13, 14 = Heliodiscus?

2. Haliomma gracile, fig. 15 = Acanthosphara1?

3. Haliomma lens, fig. 16 = Stylodiscus ?

4. Haliomma pyriforme, fig. 17 = Cenellipsis?

5. Haliomma scutum, fig. 18 = Botryocettaf

6. Haliomma polyacanthum, fig. 40 = Druppocarpus f

7. Haliomma inerme, fig. 41 = Thecosphcera ?

8. Haliomma oblongum, fig. 42 = Dmppula ?

9. Haliomma amphiaspis, fig. 43 = Monozonium,

10. Tetrapyle polyacantha, fig. 44 = Ldrcarittmf

1 1 . Flustrella cyclica, fig. 19 = Porodiscus.

12. Flustrella micromma, fig. 47 = Porodiscus.

13. Rhopalastrum bandaicum, fig. 45 = Dictyastrwn.

14. Lithocyclia reticulata, fig. 20 = Spongodiscus ?

II. NASSELLARIA.

15. Lithocircus annulus, fig. 50 = Lithocircus.

16. Acantlwdesmia arcuata, fig. 25 = Zygostephamis.

17. Acanthodesmia inermis, fig. 26 = Dictyospyris ?

18. Cladospyris moluccana, fig. 48 = Cyphonium?

19. Podocyrtis brevipes, fig. 24 = Podocyrtis. .

20. Podocyrtis micracantha, fig. 49 = Podocampe ?

21. Lithocampe corbula, fig. 21 = Lithomitra.

22. Lithocampe sinuosa, fig. 22 = Lithocampe ?

(ZOOL. CHALL. EXP. — PART XL. — 1887.) Rr 221

1762

THE VOYAGE OF H.M.S. CHALLENGER.

II. List of Fossil Radiolaria (probably Jurassic) found in the " Diaspri della Toscana,"
and described in 1880 by Dante Pantanelli (L. N. 36). (Compare § 243,
Note B, p. clxviii).

The figures are too small and too incomplete for certain determination.

I. SPUMELLARIA.

1. Ethmosphcera minuta.

2. Ethmosphcera vulgaris.

3. Eihmosphcera siphonophora.

4. Heliosphcera echinoidites.

5. Rhaphidococcus lusianensis.

6. Heliodiscus simplex.

7. Histiastrum lusianense.

8.

9.
10.
11.
12.
13.
14.

Trematodiscus soritoides.
Euchitonia muellerites.
Euchitonia amcena.
Euchitonia clathrata.
Euchitonia crevolensis.
Euchitonia grandis.
Euchitonia dubia.

II. NASSELLARIA.

15. Lithocircus haeckelii.

16. Lithocircus truncatus.

1 7. Lithocircus rhombus.

18. Cornutella pseudoprofunda.

19. Cornutella pseudoclathrata.

20. Lithopera ovata.

21. Lithopera elongata.

22. Polystichia ehrenbergii.

23. Polystichia haeckelii.

24. Polystichia muelleri.
2 5 . Urocyrtis emmce.

26. Urocyrtis amalice.

27. Urocyrtis stephanii.

28. Adelocyrtis cometa.

29. Adelocyrtis pala.

30. Adelocyrtis spinosa.

E BE AT A.

Page 23, line 3 from top, add " Compare also Myxobrachia cienkowski, Wagner, 1872, L. N. 23."
Page 40, bottom line, add "The two following species are incompletely known: — Sphcerozoum

orientale, Dana, 1863, Ann. and Mag. Nat. Hist., vol. xii. p. 54. Sphcerozoum sanderi, Dcenitz,

1871, L. K 60, p. 71."
Page 65, line 15 from top, add " Cenosphcera radiata, Zittel, 1876 (L. N". 29, p. 84, Taf. ii. figs. 7, 8),

a fossil Cretaceous species, is closely allied to Cenosphcera compacta."
Page 84, line 17 from top, add " Caryosphccra polysphcerica, Biitschli, 1882 (L. N. 41, Taf. xxiii.

fig. 12) is probably a Cromyosphcera (fossil in Barbados)."
Page 95, line 11 from top, add " Dermatosphaira, Ehrenberg, is a Collosphcera with small pores

(compare L. N. 16, p. 533)."

Page 97, line 8 from foot, for "xxiv. " read "xxxiv."
Page 122, line 14 from foot, for " Spongolonche " read " Spongolonchis."
Page 149, lines 1, 4, 6 and 12 from top, for " Spongolonche " read " Spongolonchis."
Page 149, line 2 from foot, for " Spongolonche " read " Spongoloitchis (<nroyyo?, Xoyx'V)-"
Page 172, line 4 from foot, add Synonym " 1 Haliphormis hexacantha, Ehrenberg, 1872, L. N. 24,

Taf. x. fig. 6."

Page 216, line 11 from foot, add " Taf. xiii."
Page 308, line 4 from top, add " Compare Haliomma oUongum, Harting, 1863, L. N. 18, p. 15,

pi. 2, fig. 42.

Page 326, line 14 from foot, for " 1872 " read " 1875."
Page 461, line 12 from foot, delete " H."

Page 463, line 10 from top, add " Indian Ocean, Cocos Islands, Eabbe."
Pa'ge 492, bottom line, add " Porodiscus haeckelii = Trematodiscus haeckelii, Biitschli, 1882,

L. N. 41, Taf. xxiv. figs. 5a, 5b."
Page 509, bottom line, add " Stylodictya haeckelii, Zittel, 1876, L. N. 29, p. 85, Taf. ii. fig. 9, is a

fossil Cretaceous species, related to Stylodictya multispina."
Page 534, line 11 from foot, add " Indian Ocean, Cocos Islands (Rabbe). Also in the Central

Pacific, Station 267."

Page 584, line 12 from top, for " 1872 " read " 1875."
Page 586, line 7 from foot, add " Spongotrochus ehrenbergii, Biitschli, 1882, L. N. 41, Taf. xxvi.

figs, la, 1&."
Page 633, bottom line, add " Monozonium hartingii = Haliomma amphiaspis, Harting, 1863

(L. N. 18, p. 15, pi. 2, fig. 43)."

1764 THE VOYAGE OF H.M.S. CHALLENGER.

Page 763, line 8 from top, add " PL 132, fig. 11."

Page 784, line 16 from top, for " vi." read " xvi."

Page 802, line 14 from bottom, after "lla" insert " lie."

Page 839, line 13 from top, for " 95 " read " 135."

Page 841, line 8 from foot, after " figs. " insert " 2."

Page 842, line 13 from top, add " Haliomma ligurinum, J. Miiller ( = ffaliommatidium liyurinttm,

Haeckel, L. N. 16, p. 423) seems to be closely allied to the preceding."

Page 889, line 6 from top, add " Cricoidea, Biitschli, 1882 (L N. 40, p. 537) = NASSELLARIA."
Page 951, line 9 from foot, add " Fossil in Barbados."
Page 952, line 2 from foot, add " Fossil in Barbados."
Page 966, line 10 from top, add "Fossil in Barbados."
Page 981, line 19 from top, add " Fossil in Barbados."
Page 1037, line 8 from top, add " PI. 85, fig. 2."
Page 1081, line 12 from foot, add " PI. 95, fig. 15."

Page 1158, line 10 from foot, for " 516. Cyrtophormis" read "516. Cystophormis."
Page 1165, lines 8, 11 and 15 from foot, for " Cyrtophormis" read " Cystophormis."
Page 1165, bottom line, read " Cystophormis = bladder-basket ; ICVO-TY/, <j>opfj.i<s."
Page 1166, lines 1, 7 and 13 from top, for " Cyrtophormis" read " Cystophormis."
Page 1250, line 7 from top, for " Dictyoprora " read " Dictyoprona."
Page 1251, line 11 from top, add "PI. 62, fig. 3."
Page 1356, line 9 from foot, add " PI. 68, fig. 14."
Page 1384, line 2 from foot, for " Calocycloma" read " Calocyclura."
Page 1411, first line, add " PL 68, fig. 15."
Page 1560, line 2 from top, add " Dictyocha trigona, Zittel, 1876 (L. K 29, p. 83, Taf. ii. fig. 6), is

an interesting Cretaceous species, perhaps a variety of Dictyocha triommata."
Page 1615, line 6 from top, insert " n. sp." after " scenophora."
Page 1653, line 7 from top, add " John Murray, 1876, L. N. 27, pi. 24, fig. 2,"
Page 1706, line 7 from foot, add " John Murray, 1876, L. N. 27, pi. 24, fig. 4."
Page 1752, line 4 from bottom, for " figs. la-Id " read " figs, la-lc."
Page 1757, line 14 from bottom, for " fig. 1 " read " figs. 1-13."
Page 1759, line 14 from bottom for " figs. 4a, 46 " read " figs. 4, 4a.

INDEX.

Synonyms are printed in Italics ; names of Families, Orders, &c., in SMALL CAPITALS.

ACANTHARIA, 716.

Acanthochiasma, 739.
fusiforme, 739.
krohnii, 739.
rubescens, 739.
spirale, 739.

ACANTHOCHIASMIDA, 738.

Acanthocorallium, 1262.
Acanthocoronium, 1263.
Acanthocorys, 1261.

biitschlii, 1262.

dodecaster, 1264.

enneapodia, 1263.

furcata, 1264,

hexapodia, 1262.

maeroceras, 1264.

macropodia, 1262.

polypodia, 1264.

pristipodia, 1262.

triloba, 1263.

umbellifera, 1263.
Acanthocorythium, 1264.
Acanthocyrtis, 1494.
Acanthocystis, 1461.
Acantbodesmia, 975.

arcuata, 1761.

ceratospyris, 976.

corona, 976.

dumdum, 930.

hertvigii, 983.

inermis, 1761.

miilleri, 976.

polybrocha, 930.

prismatium, 1010.

vinculata, 975.
ACANTHODESMIDA, 973.

Acantholithium, 753.
Acantholonche, 790.

ainphipolaris, 790.

peripolaris, 791.

ACANTHOLONCHIDA, 781
ACANTHOMETRA, 725.

Acanthoinetra, 742.

Acanthometra —
alata, 761.
anomale, 789.
arachnoides, 910.
lelonoides, 783.
Trrevispina, 745.
bulbosa, 743.
cataphracta, 810.
claparedei, 751.
complanata, 786.
compressa, 747.
costata, 812.
cruciate, 754.
cuspidata, 752.
dichotoma, 747.
doHchoscia, 743.
cfhinoides, 751.
elastica, 742.
elongata, 785.
forceps, 770.
fragilis, 750.
furcata, 747.
fusca, 743.
hastata, 770.
hemiwmpressa, 748.
heteracantha, 784.
lanceolata, 746.
messanetisis, 786.
mucronata, 756.
mulleri, 750.
multispina, 752.
omto, 785.
pallida, 770.
pectinata, 757.
pelludda, 744.
jmrpwrowcois, 769.
quadridentata, 758.
quadrifolia, 752.
serrata, 757.
sicula, 744.
spinulosa, 759.
tenuis, 784.
tctracopa, 749.

Acaiithometra —

Utraptera, 787.
wageneri, 744.

ACANTHOMETREA, 716.

Acanthometrella, 742.

ACANTHOMETRIDA, 725.

Acanthometron, 742.

bifidum, 745.

bulbiferum, 745.

bulbosum, 743.

catervatum, 745.

conicum, 743.

cylindricum, 743.

dolichoscion, 743.

elasticum, 742.

fuscum, 743.

pellucidum, 744.

siculum, 744.

wageneri, 744.
Acanthonarium, 749.
Acanthonia, 751.

claparedei, 751.

concava, 750.

convexa, 750.

cuspidata, 752.

denticulata, 750.

diplopyramis, 752.

echinoides, 751.

fragilis, 750.

mulleri, 750.

multispina, 752.

prismatica, 749.

quadrangula, 751.

quadrifolia, 752.

serrulata, 753.

stellata, 753.

tetracopa, 749.

ACANTHONIDA, 740.

Acanthonidium, 751.

ACANTHOPHRACTA, 791.
ACANTHOPHRACTIDA, 791.

Acauthosphsera, 209.
acauthica, 215.

1766

THE VOYAGE OF H.M.S. CHALLENGER.

Acanthosphsera —
acufera, 211.
angulata, 216.
antarctica, 214.
arctica, 214.
brevispina, 215.
capillaris, 214.
castanea, 211.
clavata, 212.
compacta, 213.
oonifera, 216.
coronata, 219.
dentata, 211.
echinoides, 214.
elliptica, 350.
enneacantha, 213.
florida, 213.
flosculenta, 211.
fortispina, 212.
gibbosa, 216.
haliphormis, 215.
insignis, 212.
longispina, 215.
macropora, 210.
marginata, 212.
maxima, 216.
micropora, 210.
mucronata, 212.
octaheclralis, 213.
pectinata, 218.
reticulata, 217.
setosa, 174.
simplex, 216.
tenuis, 210.
tennissima, 210.
zonastcr, 261.

AcANTHOSTAURIDA, 768.

Acanthostaurus, 769.

equatorialis, 769.

bipennis, 769.

conacanthus, 769.

cruciatus, 771.

forceps, 770.

hastatus, 770.

pallidus, 770.

purpurascens, 769.
Acontasparium, 829.
Acontaspidium, 829.
Acontaspis, 829.

capillata, 830.

furcata, 829.

hastata, 829.

lanceolata, 829.
Acostaurus, 769.
Acrobotrys, 1114.

acuminata, 1115.

aquaria, 1114.

auriculata, 11 15.

disolenia, 1114.

monosolenia, 1114.

Acrobotrys —

pentasolenia, 1115.

tetrasolenia, 1115.

trisolenia, 1115.
Acrocalpis, 1168.

rirginica, 1169.
Acrocorona, 1176.
Acrocoronia, 977.
Acrocubus, 992.

amphistylus, 993.

amphithectus, 994.

arcuatus, 993.

brachiatus, 993.

cortina, 994.

lasanum, 994.

octopylus, 993.

tesseralis, 993.

tetrapodius, 994.
Acromelissa, 1203.
Acropyramis, 1159.
Aerosphfera, 99.

collina, 101.

echinoides, 100.

erinacea, 100.

inflata, 101.

setosa, 100.

spinosa, 100.
ACROSPH^RIDA, 94.
ACEOSPYRIDA, 1085.
Acrospyris, 1085.

clathrocanium, 1085.

dictyophimus, 1085.

fragilis, 1086.

maerocephala, 1086.

pyramidalis, 1086.
Actidiscns, 15.

discoides, 15.

lenticularis, 15.

phacoides, 15.
Actilarcus, 16.

larcoides, 16.
Actinastrum, 733.

legitimum, 733.

pentazonium, 733.
Actinelarium, 730.

ACTINELIDA, 728.

Actinelidium, 730.
Actinelius, 730.

pallidus, 731.

polyacanthus, 731.

primordialis, 730.

protogenes, 730.

purpureus, 730.
Actinelonium, 731.
Actinomma, 251.

aculeatum, 258.

anthomma, 252.

arcadophorum, 255.

asteracanthion, 196.

capillaceuni, 255.

Actinomma —

castanomma, 253.

crenatum, 314.

dalurceforme, 164.

denticulatum, 254.

dodecomma, 256.

drymodes, 198.

entactinia, 253.

facetum, 252.

fenestratum, 315.

giganteum, 256.

hexactis, 192.

hexagonium, 252.

hirsutum, 251.

inenne, 80.

japonicum, 253.

medusa, 80.

pachycapsa, 256.

pachyderma, 254.

schwageri, 256.

sphcerechinus, 258.

spinigerum, 254.

letracanthum, 164.

trinacrium, 254.

triplex, 314.
ACTINOMMATIDA, 251.
Actinommida, 251.
Actinopyramis, 1256.
Actiprunum, 14.

ellipsoides, 14.

prunoideum, 14.

ACTIPYLBA, 716.

Actissa, 12.

discoides, 15.

ellipsoides, 14.

larcoides, 16.

lenticularis, 15.

phacoides, 13.

primordialis, 13.

princeps, 13.

prototypus, 13.

prunoides, 14.

radiata, 14.
ADELACANTHA, 717.
Adelocyrtis, 1762.

cometa, 1762.

pala, 1762.

spinosa, 1762. j
Aegospyris, 1053.

aegoceras, 1054.

aequispina, 1053.

caprina, 1054.

longibarba, 1054.

octospina, 1053.
Alacorys, 1370.

aculeata, 1373.

bismarckii, 1372.

carcinus, 1375.

dodecantha, 1375.

enneacantha, 1374.

REPORT ON THE RADIOLARIA.

1707

Alacorys —

friderici, 1372.
gigas, 1374.
gulielmi, 1372.
hexacantha, 1373.
hexapleura, 1373.
lutheri, 1370.
octacantha, 1374.
ornata, 1376.
pentacantha, 1371.
polyacantha, 1375.
tetracantha, 1371.
Ampliiactura, 470.

diplocomus, 470.
amphibrachia, 470.
Amphibelithium, 790.
Amphibelone, 788.

aciculata, 788.
anomala, 789.
clavaria, 790.
cultelliita, 789.
pyramidata, 789.
Amphibelonium, 788.
Atnphibrachium, 516.

amphilonche, 517.
armatum, 518.
capitatum, 518.
clavula, 518.
dilatatum, 517.
indicum, 518.
lanceolatum, 517.
mnrrayanum, 523.
sponguroides, 517.
Amphicentria, 614.

salpa, 614.
Amphicraspedum, 523.

maclagganium, 523.
murrayanura, 523.
wyvilleanum, 523.
Amphicyclia, 463.

amphistylia, 464.
chronornetra, 463.
pachydiscus, 464.
AMPHILITHIDA, 781.
Ampliilithium, 787.
Amphiloncharium, 783.
Araphilonche, 783.
acufera, 788.
anomala, 789.
belonoides, 783.
complanata, 786.
concreta, 787.
conica, 785.
denticulata, 784.
diodon, 783.
elongata, 785.
heteracantha, 384.
hydrotoniica, 786.
lanceolata, 783.
ancetta, 786.

Amphilonche —

messanensis, 786.

ovata, 785.

tenuis, 784.

tetraptera, 787.

violina, 787.
AMPHILONCHIDA, 781.
Amphilonchidium, 785.
Amphiplecta, 1223.

acrostoma, 1223.

amphistoma, 1223.

callistoma, 1224.
Amphipyle, 641.

aceros, 641.

amphiceros, 691.

amphiptera, 642.

callizona, 644.

cladoceros, 643.

decaceros, 643.

dodecaceros, 643.

hexaceros, 642.

octoceros, 643.

platyptera, 641.

stauroceros, 642.

stenoptera, 641.

tetraceros, 642.
Amphipylonium, 656.

octoceras, 657.

serailunare, 656.

spinosissimum, 657.

tetraceros, 657.
Amphirrhopalum, 521.

amphidicranum, 521.

bigeminum, 522.

echiuatum, 522.

ximorphum, 521.

ypsilon, 532.
Arnphisphsera, 142.

apollo, 143.

Cronos, 144.

japiter, 143.

mars, 144.

mercurius, 143.

neptunus, 142.

pluto, 144.

uranus, 143.
Amphispyridium, 1090.
Amphispyris, 1095.

costata, 1097.

quadrigemina, 1096.

reticulata, 1096.

sternalis, 1096.

subquadrata, 1097.

thorax, 1096.

toxarium, 1097.
Amphispyrium, 1095.
AMPHISTYLIDA, 142.
Amphistylus, 145.

clio, 145.

giganteus, 329.

Amphistylus —

glyptodon, 145.

hip]>ocampus, 145.

neptunus, 328.
AMPHITHOLIDA, 663.
Amphitholonium, 668.

acanthonium, 669.

octostylonium, 669.

tricolonium, 669.
Amphitholus, 666.

acanthometra, 667.

armatus, 668.

artidium, 666.

artiscus, 666.

dodecanthus, 667.

octacanthus, 667.

panicium, 668.

polyacanthus, 668.
Amphymenium, 519.

amphistylium, 520.

fusifonne, 521.

monstrosum, 520.

naviculare, 519.

pupula, 519.

zygartus, 520.
ANDROSPTEIDA, 1090.
Androspyris, 1092.

anthropiscus, 1093.

aptenodytes, 1093.

homunculus, 1092.

pithecus, 1093.
Anthocorys, 1456.

campanula, 1456.
Anthocyrtarium, 1272.
Anthocyrtella, 1269.
ANTHOCYRTIDA, 1241.
Anthocyrtidium, 1278.

cineraria, 1278.

ligularia, 1278.

matricaria, 1279.
Anthocyrtis, 1269.

butomus, 1270.

collaris, 1273.

cothurnata, 1353.

ehrenbergii, 1277.

enneapliylla, 1271.

ficus, 1277.

flosmlus, 1277.

furcata, 1269.

grossularia, 1271.

hispida, 1275.

lauranthus, 1271.

leptostyla, 1275.

mespilus, 1269.

ophirensis, 1270.

ovata, 1272.

serrulata, 1268.

sethoccmus, 1296.

setosa, 1276.

subglobosa, 1271.

1768

THE VOYAGE OF H.M.S. CHALLENGER.

Anthooyrtis —

ventricosa, 1270.

zanguebarica, 1277.
Anthocyrtissa, 1270.
Anthooyrtium, 1272.

adonis, 1273.

anemone, 1274.

anthemis, 1273.

campanula, 1274.

centaurea, 1273.

chrysanthemum, 1272.

collars, 1273.

doronicum, 1276.

ehrenbergii, 1277.

ficus, 1277.

flosculus, 1277.

hispidum, 1275.

leptostylum, 1275.

pyrum, 1276.

reticulatum, 1274.

setosum, 1276.

turris, 1275.

zanguebaricum, 1277.
Anthocyrtoma, 1268.

alterna, 1268.

serrulata, 1268.
Anthocyrtonium, 1274.
Anthocyrtura, 1271.
Anthocyrturium, 1276.
Anthomma, 76.

nodosum, 76.
Anthospyris, 1064.

aculeata, 1065.

arachnoides, 1065.

diaboliscus, 1065.

doronicum, 1065.

mamtnillata, 1064.

spathulata, 1065.

tragopogon, 1066.
Apocubus, 992.
A rachnocalpis, 1172.

ellipsoides, 1172.

sphseroides, 1173.
Arachnocorallium, 1265.
Arachnocoronium, 1266.
Arachnocorys, 1265.

arachnodiscus, 1267.

araneosa, 1266.

circumtexta, 1266.

discoides, 1265.

enneaptera, 1266.

hexaptera, 1265.

polyptera, 1267.

trifida, 1267.

umbelKfera, 1263.
Arachnocorythium, 1267.
Araclinopegma, 267.

increscens, 267.

longispinum, 267.

verticillatum, 267.

Arachnopila, 266.

hexagonella, 266.

polygonella, 266.
Arachnopilium, 1327.

clathrocanium, 1327.
Arachnosphaera, 268.

dolichacantha, 269.

increscens, 269.

myriacantha, 268.

oligacantha, 268.

tenuissima, 269.

velaris, 269.

ARACHNOSPH^RIDA, 265.
Archibursa, 1157.

tripodiscus, 1157.
Archicapsa, 1191.

nonaforis, 1192.

quadriforis, 1192.

triforis, 1191.
ARCHICAPSIDA, 1189.
Archicircus, 940.

duodenus, 942.

ellipsis, 941.

hertwigii, 942.

hexacanthus, 942.

monopylus, 941.

monostephus, 941.

ovalis, 941.

primordialis, 942.

princeps, 940.

quadratus, 941.

rhombus, 942.

sexangularis, 943.

triglyphus, 943.
ARCHICORIDA, 1180.
Archicorys, 1184.

ampulla, 1184.

galea, 1184.

globosa, 1185.

microstoma, 1185.

ovata, 1185.
ARCHIDISCIDA, 485.
Archidiscus, 486.

diouiscus, 486.

dithalamius, 486.

hexathalamus, 489.

hexoniscus, 488.

octoniscus, 489.

pentoniscus, 488.

polythalamus, 489.

pyloniscus, 488.

stauroniscus, 487.

tetrathalamus, 487.

tetroniscus, 487.

trioniscus, 487.

trithalamius, 487.
Archipera, 1155.

bicornis, 1156.

cortiniscus, 1155.

multicornis, 1156.

Archipera —

pentacantha, 1155.

quadricornis, 1155.

tricornis, 1156.
AHCHIPERIDA, 1146.
Archiperidium, 1154.
Archiphseua, 1177.

corona, 1178.

gorgospyris, 1178.

stephauoma, 1178.
AP.CHIPHJENIDA, 1173.
ARCHIPHORMIDA, 1159.
Archiphormis, 1167.

campanulata, 1165.

cancellata, 1167.

urceolata, 1168.
ARCHIPILIDA, 1135.
Archipilium, 1139.

cyrtopterum, 1140.

orthopterum, 1139.

sigmopterum, 1139.
Archiscenium, 1150.

callimitra, 1151.

clathrocorys, 1150.

cyclopterum, 1151.

quadrispinum, 1150.

tricolpium, 1147.

tripterygium, 1151.
Archistephus, 941.
Artidium, 356.
ARTINIDA, 354.
Artiscium, 355.
Artiseus, 355.

elegans, 356.

facetus, 355.

hystrix, 356.

nodosus, 356.

panarius, 356.

paniculus, 355.

paniscus, 355.
Artocapsa, 1519.

armata, 1520.

elegans, 1520.

fusiformis, 1519.

infraculeata, 1519.

octocamera, 1520.

quadricamera, 1520.

spinosa, 1519.
ARTOCAPSIDA, 1467.
ARTOCOHIDA, 1467.
Artocyrtis, 1490.
Artopera, 1452.

fusiformis, 1452.

loxia, 1452.

motacilla, 1452.

thoracoptera, 1460.
ARTOPERIDA, 1435.
Artophiena, 1463.

serostatica, 1463.

hexalatractus, 1464.

REPORT ON THE RADIOLARIA.

1769

Artophsena —

hexapodiscus, 1464.

senaria, 1464.
ARTOPHSNIDA, 1453.
AKTOPHOBMIDA, 1453.
Artophormis, 1458.

barbadensis, 1459.

costata, 1459.

horrida, 1458.
ARTOPILIDA, 1435.
Artopilium, 1439.

anomalum, 1442.

cornutella, 1441.

cyrtopterum, 1440.

clegaus, 1440.

longicorne, 1440.

stiehopterygium, 1442.

trifenestra, 1441.

trigonopterum, 1441.
Artostrobium, 1482.
Artostrobulus, 1481.
Artostrobus, 1481.

annulatus, 1481.

articulatus, 1482.

auritus, 1482.

biseriatus, 1482.

elegans, 1482.
Aspidomma, 847.

hystrix, 854.

mucronatum, 756.
Astractinium, 476.
Astractura, 476.

aristotelis, 476.

elavigera, 476.

democriti, 477.

hippocratis, 477.

ordinata, 476.
ASTRACTURIDA, 469.

Astracturium, 476.
Astrocapsa, 799.

coronata, 799.

quadrifida, 799.

stellata, 799.

tritonis, 799.
ASTROCAPSIDA, 797.
Astrocyclia, 466.

arachnia, 467.

heterocycla, 468.

rotula, 467.

solaster, 466.

stella, 467.

ASTROCYRTIDA, 1129.
A.STROLITHIDA, 726.

Astrolithium, 745.

Ufidum, 745.

tulbiferum, 745.

erueiatum, 771.

dicopum, 748.
Astroloncharinm, 756.
Astrolonche, 756.

(ZOOL. CHALL. EXP. PART XL.-

Astrolonche —

bicruciata, 756.
mucronata, 756.
pectiuata, 757.
pinnata, 757.
serrata, 757.

ASTROLONCHIDA, 740.

Astrolonchidium, 757.

ASTBOLOPHIDA, 728.

Astrolophus, 732.

solaria, 732.

stellaris, 732.
Astromma, 475.

aristotelis, 476.

entomocora, 367.

pentactis, 479.

pythagorce, 471.
Astrophacus, 453.

apollinis, 455.

asteriscus, 453.

cingillum, 454.

phacodiscus, 454.

saturnus, 454.

Solaris, 453.

trochiscus, 453.
Astrosestrum, 442.

acanthastrum, 443.

acraspedum, 443.

caudatum, 431.

echinastrum, 443.

ephyra, 442.

floscula, 444.

nanphanta, 442.

octacanthum, 442.

pelagia, 444.
Astrospbsera, 250.

hexagonalis, 250.

splendens, 250.

sidersea, 251.

stellata, 251.
ASTROSPHJERIDA, 206.

Astrostaurus, 436.

magnificus, 436.
Astrostylus, 431.
Atactodiscus, 497.

irregularis, 498.
Aulacantha, 1575.

cannulata, 1576.

clavata, 1576.

luevissima, 1576.

scolymantha, 1575.

spinosa, 1575.

tubulosa, 1575.
AULACANTHIDA, 1569.
AULACTINIDA, 1573.

Aulactinium, 1574.

actinastrum, 1574.
actinelium, 1574.
actinosphserium, 1574.
Aularia, 1621.
1887.)

Anlaria —

ternaria, 1621.

trigonaria, 1621.

tubularia, 1621.
AULARIDA, 1620.
Aulastrum, 1635.

dendroceros, 1635.

dichoceros, 1635.

monoceros, 1635.

pentaceros, 1636.

polyceros, 1636.

tetraceros, 1636.

triceros, 1635.

trichoeeros, 1636.
Aulatractus, 1632.

diploconus, 1632.

ellipsoides, 1633.

fusifonnis, 1632.

fusulus, 1632.
Aulocersea, 1583.
Auloceratium, 1585.
Auloceros, 1583.

arboreseeus, 1585.

capreolus, 1584.

cervinus, 1584.

dicranaster, 1585.

elegans, 1584.

furcosus, 1583.

spathillaster, 1585.

trigeminus, 1584.
Aulodendron, 1588.

antarcticum, 1589.

atlanticum, 1589.

australe, 1589.

indicum, 1590.

pacificum, 1589.
Aulodictyum, 1637.

hydrodictyum, 1637.
Aulographanta, 1577.
Aulographella, 1579.

AULOORAPHIDA, 1574.

Aulographidium, 1580.
Aulographis, 1577.

asteriscus, 1581.

ancorata, 1578.

bovicornis, 1577.

candelabrum, 1582.

cruciata, 1578.

dentata, 1582.

flammabunda, 1579.

flosculus, 1580.

furcula, 1580.

gemmascens, 1580.

hexancistra, 1581.

martagon, 1579.

pandora, 1577.

penicillata, 1578.

pistillum, 1579.

polyancistra, 1581.

pulvinata, 1582.

Er222

1770

THE VOYAGE OF H.M.S. CHALLENGER.

Aulographis —

serrulata, 1582.
stellata, 1578.
taumorpha, 1577.
tetrancistra, 1581.
triaena, 1579.
triangulum, 1580.
triglochin, 1578.
tripentas, 1582.
verticillata, 1582.
Aulographonium, 1581.
Aulonia, 1633.

hexagonia, 1634.
metagonia, 1634.
pentagonia, 1634.
polygonia, 1634.
tetragonia, 1633.
AULONIDA, 1633.
Aulophacus, 1631.

amphidiscus, 1631.
lenticularis, 1631.
Auloplegma, 1630.

perplexum, 1630.
spongiosum, 1631.
Auloscena, 1628.

arboretum, 1629.
flammabunda, 1629.
gigantea, 1629.
mirabilis, 1628.
penicillus, 1629.
pyramidalis, 1628.

serrata, 1630.

spectabilis, 1628.

tentorium, 1628.

verticillus, 1629.
Aulospathessa, 1586.
Aalospathilla, 1587.
Aulospathis, 1586.

bifurca, 1586.

diodon, 1587.

furcata, 1588.

hexodon, 1588.

polymorpha 1587.

quadrifurca, 1587.

tetrodon, 1588.

trifurca, 1586.

triodon, 1587.

variabilis, 1588.
Aulosphsera, 1622.

bifurca, 1626.

bisternaria, 1624.

coronata, 1626.

cruciata, 1624.

dendrophora, 1625.

diodon, 1523.

elegantissima, 1624.

flexuosa, 1622.

gracilis, 1609.

multifurca, 1626.

polyodon, 1623.

Aulosphasra —

pourtalcsii, 1624.

quadrifurca, 1626.

sceptrophora, 1625.

spathillata, 1624.

spathophora, 1625.

spinosa, 1627.

tetrodon, 1623.

trifurca, 1626.

trigonopa, 1622.

triodon, 1623.

undulata, 1627.

verticillata, 1624.
AITLOSPH.ERIDA, 1615.
Axellipsis, 293.

lobata, 293.

perforata, 293.
Axocorys, 1420.

macroceros, 1420.
Axodiscus, 490.

hexagonus, 490.

octogonus, 491.

spinosus, 491.

staurophorus, 490.

stylophorus, 490.

trigonus, 490.

triradiatus, 490.
Axoprunum, 298.

stauraxonium, 298.

Bathropyramis, 1159.

acephala, 1159.

interrupta, 1160.

medusa, 1160.

quadrata, 1159.

ramosa, 1161.

spinosa, 1160.

trapezoides, 1160.
BELOIDEA, 28.
BELONASPIDA, 859.
Belonaspis, 863.

conifera, 864.

datura, 863.

furcata, 863.

lanceolata, 864.

multiforis, 864.

pandanus, 863.
Belonostaurus, 771.

bicuspis, 772.

quadratus, 771.
Belonozoum, 39.

atlanticum, 40.

bacillosum, 39.

italicnm, 40.

spinulosum, 40.
BOTRIDA, 1103.

BOTRYIDA, 1103.
Botryocampe, 1122.

camerata, 1124.

galea, 1123.

Botryocampe —

hexathalamia, 1125.
inflata, 1123.
rotalia, 1123.
theocapsa, 1123.

BOTRYOCAMPIBA, 1120.

Botryocella, 1116.

borealis, 1116.
multicellaris, 1112.
nucula, 1116.
quadricellaris, 1117.
quadrigemina, 1117.
tricellaris, 1116.

BOTKYOCELLIDA, 1112.
BOTRYOCYRTIDA, 1120.

Botryocyrtis, 1120.

cerebellum, 1121.
quinaria, 1121.
serpentis, 1120.
theocampe, 1121.

BOTRYODEA, 1108.

Botryopera, 1108.

cyrtoloba, 1108.

multiloba, 1109.

quadriloba, 1109.

triloba, 1108.
Botryopyle, 1112.

cephalodes, 1113.

cribrosa, 1113.

dictyocephalus, 1113.

inclusa, 1113.

sethocorys, 1112.

BOTRYOPYLIDA, 1112.

Botryostrobus, 1475.
Bracbiospyris, 1037.

diacantha, 1038.

ocellata, 1038.
Buccinosphaera, 99.

invaginata, 99.

tubaria, 99.

Callimitra, 1216.

aguesse, 1217.

anuae, 1217.

carolotse, 1217.

elisabethse, 1218.

emmse, 1218.
Calocyclas, 1381.

arnica:, 1282.

aspasiie, 1385.

barbadensis, 1459.

carciims, 1375.

casta, 1384.

erinaceus, 1383.

gigas, 1384.

hyalogaster, 1383.

minervie, 1382.

monumentum, 1385.

pavtheuia, 1385.

pudica, 1384.

REPORT ON THE RADIOLARIA.

1771

Caloeyelas—

sacerdotis, 1382.

turris, 1383.

veneris, 1381.

vestalis, 1382.

virginis, 1381.
Calocycletta, 1381.
Calocyclissa, 1383.
Calocycloma, 1384.
CALODICTYA, 481.
Calpocapsa, 1190.
Calpophiena, 1175.

enneaphylla, 1176.

ennearrhabda, 1176.

hexacorethra, 1177.

hexarrhabda, 1176.

petalospyris, 1177.

tetracorethra, 1177.

tetrarrhabda, 1176.
Caminosphsera, 111.

dendrophora, 112.

dichotoma, 112.

elongata, 111.

furcata, 111.
Cannartidium, 373.

ampliicanna, 374.

amphiconicum, 373.

amphiconus, 372.

ampliisiphon, 374.

bicinctum, 374.

mammiferum, 375.

mastophorum, 375.

tubarium, 339.
Cannartiscus, 372.

amphiconiscus, 372.

amphicylindrus, 373.
Cannartus, 358.

biscottus, 359.

bitubulus, 359.

violina, 358.
CANNOBELIDA, 1551.
Cannobelos, 1551.

calymmata, 1551.

cavispicula, 1551.

thalassoplancta, 1551.
CANNOBOTRYIDA, 1107.
Cannobotrys, 1109.

cortina, 1110.

dicanna, 1110.

monocanna, 1110.

pentacanna, 1111.

sagittalis, 1110.

tetracanna, 1111.

tricanna, 1110.
Cannocapsa, 801.

osculata, 801.

stethoscopium, 801.

tubulosa, 801.
Cannopilus, 1567.

calyptra, 1568.

Cannopilns —

eyrtoides, 1569.

diplostaurus, 1568.

hemisphsericus, 1569.

superstructus, 1568.
CANNOPYLEA, 1521.
CANNORRHAPHIDA, 1546.
Cannorrhaphis, 1552.

cavispicula, 1551.

lampoxanthium, 1552.

lappacea, 1552.

spathillata, 1552.

spinulosa, 1552.
Cannosphaera, 1640.

antarctica, 1640.

atlantica, 1640.

pacifica, 1641.
CANNOSPILERIDA, 1637.
Cantharospyris, 1050.

ateuchus, 1051.

carabus, 1051.

platybursa, 1051.

radicata, 1051.
CAPSOPHRACTA, 793.
Carpocanarium, 1279.
Carpocanidium, 1280.
Carpocanistrum, 1170.

acephalura, 1171.

evacuatum, 1172.

flosculum, 1171.

giganteum, 1171.

novenum, 1171.

pyriforme, 1172.
Carpocanium, 1279.

arachnodiscus, 1164.

calycodes, 1279.

campanula, 1144.

cornutum, 1398.

coronatum, 1284.

cyliudricum, 1281.

dactylus, 1284.

diadema, 1281.

enneapbyllum, 1281.

gemmula, 1282.

hexagonale, 1282.

irregulare, 1284.

Iseve, 1280.

lanceolatum, 1280.

macropteruni, 1283.

microdon, 1282.

palmipes, 1283.

peristomium, 1283.

petalospyris, 1283.

polypterum, 1283.

setosum, 1280.

solitarium, 1281.

trepauium, 1282.

verecuudum, 1284.

virgineum, 1285.
Carpocanobium, 1282.

Carposphsera, 71.

apiculata, 73.

areca, 74.

belladonna, 74.

borassus, 75.

capillacea, 72.

cerasus, 73.

corypha, 75.

cubaxonia, 72.

entactinia, 74.

infundibulum, 72.

maxima, 76.

melissa, 73.

melitomma, 73.

micrococcus, 75.

modesta, 74.

nobilis, 75.

nodosa, 76.

prunulum, 74.
CARPOSPH.SRIDA, 71.
Caryomma, 265.

irregulare, 266.

regulare, 265.
CARYOMMIDA, 266.
Caryosphaera, 86.

hexalepas, 86.

pentalepas, 86.

polysphaerica, 1763.
CARYOSPH.ERIDA, 85.
CARYOSTYLIDA, 148.
Caryostylus, 148.

ceparius, 336.

cepicius, 336.

hexalepas, 148.
Castanarium, 1681.

darwini, 1681.

hookeri, 1682.

huxleyi, 1682.

lubbocki, 1682.

lyeUi, 1682.
Castanella, 1683.

balfouri, 1683.

campbelli, 1683.

channeri, 1684.

horstoni, 1684.

sloggetti, 1683.

thomsoni, 1683.

wyvillei, 1683.
CASTANELLIDA, 1677.
Castanidium, 1684.

aldrichii, 1685.

bethelli, 1685.

bromleyi, 1685.

buchanani, 1685.

moseleyi, 1686.

murrayi, 1685.

wildi, 1684.

willemoesi, 1684.
Castanissa, 1686.

challengeri, 1686,

1772

THE VOYAGE OF H.M.S. CHALLENGER.

Castanissa —

crosbiei, 1687.
hoylei, 1687.
macleani, 1687.
pearceyi, 1686.
richardsi, 1687.
Caatanopsis, 1688.

fergusoni, 1688.
maclearei, 1688.
naresi, 1688.
Castanura, 1689.

carpenteri, 1689.
havergalli, 1689.
swirei, 1689.
tizardi, 1689.
CATINTTUDA, 1553.
Catinulus, 1553.

catillum, 1553.
lopadium, 1553.
quadrifidus, 1553.
Cecryphalium, 1398.

lamprodiscus, 1398.
sestrodiscus, 1399.
Cenellipsis, 291.

circopora, 291.
ehrenbergii, 291.
faceta, 291.
heteropora, 292.
infundibulum, 292.
maxima, 292.
micropora, 291.
oblonga, 293.
ovulum, 292.
primitiva, 291.
Cenellipsium, 290.
Cenellipsula, 292.
Cenocapsa, 802.

nirvana, 802.
CENOCAPSIDA, 802.
CBNODISCIDA, 409.
Cenodiscus, 411.

lenticula, 412.
phacoides, 411.
rotula, 412.
CBNOLAKCIDA, 606.
Cenolarcus, 606.

diraensivus, 607.
lentellipticus, 607.
minimus, 607.
primordialis, 607.
triaxonius, 607.
Cenosphsera, 62.

acanthica, 215.
anthophora, 63.
antiqua, 67.
aspera, 68.
bombus, 63.
compacta, 65.
coronata, 67.
crassa, 65.

Cenosphsera —

cristata, 66.
elysia, 64.
eridani, 64.
favosa, 62.
gigantea, 67.
hexagonalis, 62.

hirsuta, 68.
in. Tin k 62.

lethe, 64.

marginata, 67.

maxima, 65.

megapora, 155.

melecta, 63.

mellifica, 62.

micropora, 155.

nirwana, 65.

papillata, 66.

perforata, 66.

plutonis, 64.

polygonalis, 66.

porophsena, 63.

primordialis, 61.

proserpinse, 64.

radiata, 1763.

reticulata, 66.

rosetta, 63.

setosa, 64.

solida, 65.

tenerrima, 66.

vesparia, 62.
Centrocubus, 278.

cladostylus, 278.

octostylus, 278.

polystylus, 278.
Centrospira, 495.

perispongidium, 495.
Cephalopyramis, 1253.

enneactis, 1254.
Cephalospyris, 1034.

cancellata, 1035.

ovata, 1035.

triangulata, 1035.
Cerasosphsera, 73.
Ceratocyrtis, 1281.

ampliata, 1291.

cucitllaris, 1290.

mitra, 1291.
Ceratospyris, 1065.

acuminata, 1080.

allmersii, 1067.

articulata, 1048.

ateuchus, 1051.

borealis, 1075.

calorrhiza, 1069.

carnerii, 1069.

davata, 1028.

diatantha, 1038.

didiceros, 1030.

dirrhiza, 1039.

Ceratospyris —

echinus, 1068.

fibula, 1082.

furcata, 1031.

heptaceros, 1038.

krausei, 1068.

longibarba, 1054.

miilleri, 1068.

mulderi, 1067.

ocellata, 1038.

pentagona, 1067.

polygona, 1066.

preyeri, 1068.

radicata, 1051.

ramosa, 1069.

setigera, 1047.

strasburgeri, 1068.

stylophora, 1038.

triceros, 1033.

triomma, 1047.

turrita, 1050.
Ceriasparium, 819.
CERIASPIDA, 813.
Ceriaspidium, 820.
Ceriaspis, 820.

cicatricosa, 821.

favosa, 821.

icosahedra, 821.

inermis, 821.

lacunosa, 820.

scrobiculata, 820.
Ceriosphsra, 66.

perforata, 66.
Challengeranium, 1653.
Challengerantha, 1648.
Challengerebium, 1655.
Challengeretta, 1649.
Challengeria, 1694.

aldrichii, 1653.

balfouri, 1655.

bidens, 1650.

bromleyi, 1652.

campbelli, 1650.

cyrtodon, 1649.

elephas, 1651.

harstoni, 1650.

havergalli, 1651.

macleari, 1651.

murrayi, 1653.

naresii, 1648.

pyramidalis, 1649.

quadridens, 1652.

sigmodon, 1649.

sloggettii, 1649.

swirei, 1654.

thomsoni, 1650.

tizardi, 1656.

tridens, 1651.

triBda, 1652.

trigona, 1652.

REPORT ON THE RADIOLARIA.

1773

Challengeria —

tritonis, 1649.

wildi, 1653.

xiphodon, 1648.
CHALLENOERIDA, 1642.
Challengeridium, 1656.
Challengerilla, 1651.
Challengeroma, 1652.
Challengeron, 1654.

balfouri, 1655.

bathybium, 1658.

bethelli, 1658.

bisteroum, 1657.

buchanani, 1657.

carpenterii, 1659.

channeri, 1658.

ciliatum, 1659.

cochlear, 1654.

crosbiei, 1657.

diodon, 1654.

fergusoni, 1656.

golfense, 1655.

heptacanthum, 1657.

johannis, 1659.

monodon, 1654.

moseleyi, 1658.

pearceyi, 1654.

richardsii, 1655.

swirei, 1654.

tizardi, 1656.

triangulum, 1656.

triodon, 1655.

willemoesii, 1659.

wyvillei, 1660.
Challengerosium, 1658.
CHIASTOLIDA, 736.
CHIASTOLIDINA, 738.
Chiastolus, 738.

amphicopium, 738.
Chilomma, 454.

saturnus, 454.
Chitonastrum, 537.

bathybium, 537.

dicranoidcs, 538.

jugatum, 537.

lyra, 538.

regulars, 539.

triglochin, 537.
Chcenicosphffira, 102.

flammabunda, 103.

flosculenta, 103.

murrayana, 102.

nassiterna, 103.
Cinclopyramis, 1161.

cribellum, 1161.

infundibulum, 1161.

lithosestrum, 1162.
Circogonia, 1698.

dodecacantha, 1698.

icosahedra, 1698.

CIRCOGONIDA, 694.
Circoniscus, 489.
CIKCOPOEIDA, 1689.
Circoporus, 1694.

characeus, 1695.

hexastylus, 1695.

octahedras, 1695.

sexfurcus, 1694.

sexfuscinus, 1695.
Circorrhegma, 1699.

dodecahedra, 1699.
Circospathis, 1696.

furcata, 1696.

novena, 1696.

tetradeca, 1697.

tetrodonta, 1697.
Cireosphsera, 63.
CIRCOSPYKIDA, 1072.
Circospyris, 1072.

gigas, 1072.

nucula, 1072.

tridentata, 1072.
Circostephanus, 1699.

eoronarius, 1699.

polygonarius, 1700.

sexagenarius, 1700.
Circotympanum, 1012.

decagonium, 1013.

hexagonium, 1012.

octogonium, 1013.
Cladarachnium, 1165.

virgultum, 1296.

ramosum, 1165.
CLADOCOCCIDA, 51.
Cladococcus, 223.

abietinus, 226.

acufer, 211.

antarcticus, 225.

arborescens, 224.

bifurcus, 226.

cenricornis, 228.

dentatus, 211.

dendrites, 227.

japonicus, 225.

penicillus, 224.

pinetum, 226.

quadricuspis, 225.

scoparius, 225.

simplex, 216.

spinifer, 224.

stalactites, 227.

tricladus, 227.

viminalis, 226.
Cladocorona, 1177.
CLADOPHRAOTA, 803.
Cladopyramis, 1160.
Cladoscenium, 1148.

ancoratum, 1149.

fulcratum, 1148.

gladiatum, 1149.

Cladoscenium —

pectinatum, 1150.

pinnatum, 1149.

verticillatum, 1149.
Cladospyris, 1069.

bibrachiata, 1039.

moluccana, 1761.

ramosa, 1069.

tribrachiata, 1029.
Clathrobursa, 1045.

dietyopus, 1045.
Clathrocanidium, 1210.
Clathrocanium, 1210.

coarctatum, 1211.

diadema, 1212.

ehreiibergii, 1262.

reginse, 1212.

sphaerocephalum, 1211.

squarrosum, 1211.

triomma, 1211.
Clathrocorona, 1212.

diadema, 1212.

regime, 1212.
Clathrocorys, 1219.

giltschii, 1220.

murrayi, 1219.

teuscheri, 1220.
Clathrocircus, 961.

decaporus, 962.

dictyospyris, 963.

hexaporus, 962.

multiforis, 963.

octoporus, 962.

stapedius, 962.
Clathrocyclas, 1385.

alcmense, 1388.

basilea, 1386.

cassiopeise, 1390.

collaris, 1387.

coscinodiscus, 1389.

danaes, 1388.

domina, 1387.

europse, 1388.

fimbriata, 1386.

jonis, 1389.

latonse, 1389.

principessa, 1386.

puella, 1387.

semeles, 1388.
Clathrocyclia, 1386.
Clathrolychnus, 1240.

araneosus, 1240.

periplectus, 1241.
Clathromitra, 1218.

pentacantha, 1219.

pterophormis, 1219.
Clathropilium, 1326.
Clathropyrgus, 1441.

trifenestra, 1441.
Clathrosphsera, 118.

1774

THE VOYAGE OF H.M.S. CHALLENGER.

Clathrosphffira —

arachnoides, 119.

circumtexta, 118.

lamellosa, 119.
CLATHROSPH.ERIDA, 118.
Clathrospyris, 1052.

camelopardalis, 1052.

fusiformis, 1053.

pyramidalis, 1052.
Clistophaena, 1286.

armata, 1288.

enneolena, 1288.

hexolena, 1287.

polyolena, 1288.

pyramidalis, 1287.

riistiana, 1287.
Coccocyclia, 468.

heliantha, 468.

liriantha, 468.
COCCODISCIDA, 455.
Coccodiscus, 461.

darwinii, 461.

goethei, 461.

lamarckii, 461.

COCCOLARCIDA, 610.

Coccolarcus, 610.

lentellipsis, 610.

platellipsis, 610.
Coecostaurus, 466.

magniducia, 466.
Coelacantha, 1641.

anchorata, 1641.

mammillata, 1641.
Ccelagalma, 1759.

mirabile, 1759.
Ccelodasea, 1739.

ramosissima, 1739.

spongiosa, 1739.
Coelodecas, 1755.

decastyla, 1755.

pentagona, 1756.

sagittaria, 1755.

CfELODENDRIDA, 1728.

Coelodendrum, 1735.

bifurcum, 1735.

eervicorne, 1736.

digitatum, 1736.

flabellatum, 1737.

furcatissimum, 1735.

gracillimum, 1736.

lappaceum, 1736.

ramosissimum, 1735.

serratum, 1737.

spinosissimum, 1735.
Coelodoras, 1734.

hexagraphis, 1734.

octographis, 1734.

COSLODORIDA, 1733.
ClELODRYMIDA, 1737.

Ccelodrymus, 1738.

Ccelodrymus—

ancoratus, 1738.
eehinatus, 1738.
lappulatus, 1738.

CtELOGRAPHIDA, 1739.

Ccelographis, 1752.

gracillima, 1753.

hexastyla, 1753.

regina, 1752.

sagittella, 1753.

triangulum, 1753.
Coeloplegma, 1757.

atlanticum, 1758.

murrayanum, 1757.

tetradecastylura, 1758.

tritonis, 1758.

C<ELOPLEGMIDA, 1752.

Ccelospathis, 1754.

ancorata, 1754.

octodaetyla, 1755.

octostyla, 1754.
Ccelostylus, 1756.

bisenarius, 1756.

flabeljatus, 1757.
Ccelothamnus, 1751.

bivalvis, 1751.

davidoffi, 1751.

maximus, 1752.

sedecimalis, 1751.
Ccelothauma, 1750.

duodenum, 1750.

CcELOTHOLIDA, 1749.

Coelotholus, 1749.

ancoratus, 1749.

cruciatus, 1749.

octonus, 1749.
COLEASPIDA, 861.
Coleaspis, 867.

amphilonche, 867.

coronata, 866.

hydrotomica, 867.

obscura, 866.

occulta, 867.

vaginata, 866.

COLLIDA, 9.
COLLODARIA, 9.

Collodastrum, 27.

amreboides, 28.

pelagicum, 28.

stellatum, 28.
Collodinium, 24.

inerme, 25.

nostochinum, 25.

volvocinum, 25.
Collodiscus, 27.

cosrulcus, 27.

discoideus, 27.
COLLOIDEA, 10.
Collophidium, 26.

contortum, 26.

Collophidium —

serpentinum, 26.

vermiforme, 27.
Colloprunum, 25.

ovatum, 25.

ellipsorides, 26.
Collosphsera, 95.

globularis, 95.

huxleyi, 96.

irregularis, 97.

ligurina, 97.

polyhedra, 97.

polygona, 96.

primordialis, 95.

pyriformis, 96.

regularis, 95.

spinosa, 100.

tuberosa, 97.

tubulosa, 105.
COLLOSPH^RIDA, 92.
COLLOZOIDA, 23.
Collozoum, 24.

ameeboides, 28.

contortum, 26.

coeruleum, 27.

discoideum, 27.

ellipsoides, 26.

inerme, 25.

nostochinum, 25.

ovatum, 25.

pelagicum, 28.

serpentinum, 26.

stellatum, 28.

vermiforme, 27.

volvocinum, 25.
Conarachinum, 1290.

rayanum, 1291.

cervus, 1292.
lophophsena, 1592.

trochus, 1290.

CONCHARIDA, 1710.

Concharium, 1716.

bacillarium, 1718.

bivalvum, 1717.

diatomeum, 1717.

fragilissimum, 1718.

nucula, 1717.
Conchasma, 1718.

hippurites, 1719.

radiolites, 1719.

sphaerulites, 1719.

CONCHASMIDA, 1716.

Conchellium, 1720.

hippopus, 1720.

tridacna, 1720.
Conchidium, 1721.

argiope, 1722.

dimerella, 1722.

leptama, 1722.

magasella, 1723.

REPORT ON THE RADIOLARIA.

1775

Conchidium —

productum, 1723.

rhynchonella, 1722.

terebratula, 1721.

thecidium, 1721.
Conchoccras, 1727.

caudatum, 1727.

cornutum, 1728.
Conchonia, 1723.

diodon, 1723.

tetrodon, 1724.

triodon, 1724.
CONCHOPSIDA, 1719.
Conchopsis, 1724.

aspidium, 1726.

carinata, 1725.

compressa, 1725.

lenticula, 1726.

navicula, 1727.

orbicularis, 1725.

pilidium, 1726.
ConcJiura, 1724.

tetrodon, 1724.
Conosphsera, 221.

orthoconus, 221.

plagioconus, 222.

platyconus, 221.
Conostrobus, 1469.
Cornustrobus, 1470.
Cornutanna, 1183.

cyrtoconus, 1184.

loxoconus, 1184.

orthoconus, 1183.
Cornutella, 1180.

ampliata, 1291.

annulata, 1182.

bimarginata, 1295.

cassis, 1301.

circularis, 1181.

clathrata, 1182.

cullaris, 1290.

curvata, 1183.

distenta, 1181.

granulata, 1182.

hexagona, 1180.

longiseta, 1294.

mitra, 1181.

oUusa, 1308.

orthoceras, 1294.

profuiida, 1284.

pseudoprofunda, 1762.

pseudodathrata, 1762.

quadratella, 1254.

scalaris, 1203.

sethoconus, 1180.

spiniccps, 1303.

spiralis, 1183.

stiligera, 1181.

stylopluena, 1182.

trichostyla,, 1294.

Cornutella —

trochus, 1293.

tumcns, 1182.

mmicosa, 1293.
Cornutellium, 1180.
Cornutissa, 1181.
Cornutosa, 1183.

clathrata, 1183.
Corocalyptra, 1322.

agnesa;, 1323.

elisabethse, 1323.

emrnje, 1323.

ludovicae, 1324

margarethae, 1323.
COROCYRTIDA, 1129.
CORONIDA, 967.
Coronidium, 973.

acacia, 975.

cervicorne, 974.

diadeina, 974

dyostephanus, 974.
Coronophsena, 1178
Coronosphsera, 117.

diadema, 117 •

calycina, 117.

convolvulus, 117.
Cortina, 950.

cervina, 952.

conifera, 951.

dendroides, 951.

furcata, 951.

tripus, 950.

typus, 951.
Cortinetta, 1667.

cortiniscus, 1667.

tripodiscus, 1667.

COETINIDA, 950.
COKTINISCIDA, 963.

Cortiniscus, 963.

dipylaris, 964.

tetrapylaris, 964.

tripodiscus, 963.

tripylaris, 964.

typicus, 964.
Corythospyris, 1057.
Coscinasparium, 826.
Coscinaspidium, 828.
Coscinaspis, 826.

ceriopora, 826.

coscinopora, 826.

isopora, 828.

orthopora, 827.

parmipora, 827.

peripora, 825.

polypora, 827.

rhacopora, 827.

stigmopora, 826.
Coscinomma, 222.

amphisiphon, 222.

ectosiphon, 222.

Coscinomma —

endosiphon, 223.
macrosiphon, 223.

COSCINOMMIDA, 209.

Craniaspis, 827.

parmipora, 827.
Craspedilium, 1247.

eupilium, 1247.
Craspedomma, 77.
CRICOIDEA, 889.
Cromyatractus, 335.

ceparius, 336.

cepicius, 336.

tetracelyphus, 335.

tetralepus, 335.

tetraphractus, 335.
Cromyechinus, 263.

dodecacanthus, 264.

icosacanthus, 263.

polyacanthus, 264.
Cromyocarpus, 318.

quadrifarius, 318.
Cromyodruppa, 317.

cepa, 317.

mango, 318.
Cromyodrymus, 264.

abietinus, 265.

quadricuspis, 264.
Cromyomma, 261.

circumtextuin, 262.

macroporum, 262.

mucronatum, 263.

perplexum, 261.

perspicuum, 262. '

quadruples, 262.

villosum, 261.

zonaster, 261.
CEOMYOMMIDA, 260.
Cromyosphaera, 85.

antarctica, 85.

bigemina, 85.

cepa, 85.

perspinui, 262.

quadruplex, 84.

rosetta, 84.

scorodonium, 85.
CROMYOSPH.ERIDA, 84.
Cromyostaurus, 167.

verticillatus, 167.
CROMTOSTYLIDA, 146.
Cromyostylus, 147.

gladius, 147.
Crucidiscus, 415.

cruciatus, 416.

cuspidatus, 416.

echinatus, 416.

endostaurus, 416.
Cryptocapsa, 1312.
bacca, 1313.
pila, 1313.

1776

THE VOYAGE OF H.M.S. CHALLENGER.

Cryptocephalus, 1252.

favosus, 1252.
Cryptoprora, 1252.

microstonut, 1252.

ornata, 1375.

plutonis, 1252.

polyptera, 1283.
Cnbaxonium, 204.

octahedrum, 204.

spongiosum, 204.
Cubosphiera, 203.

concentrica, 203.

cubaxonia, 203.
CTOOSPH.I;RIDA, 169.

ClTBOTHOLIDA, 677.

Cubotholonium, 682.

ellipsoides, 682.

sphffiroides, 682.
Cubotholus, 680.

octoceras, 681.

quadraticus, 680.

regularis, 680.

rhombicus, 681.
Cycladophora, 1376.

campanula, 1379.

davisiana, 1437.

di&oides, 1397.

dodecapleura, 1378.

enneapleura, 1378.

erinaceus, 1383.

favosa, 1380.

fenestrata, 1380.

goetheana, 1375.

gigas, 1384.

hexapleura, 1377.

lanterna, 1377.

nonagona, 1378.

pantheon, 1379.

pyramidalis, 1377.

spatiosa, 1379.

spinosa, 1378.

stiligera, 1380.

tabulate, 1293.

tetrapleura, 1376.
Cyclampterium, 1371.
Cyclamptidium, 1380.
CYCLODISCARIA, 409.
Cypassis, 366.

entomocora, 367.

eucolpos, 867.

halicora, 368.

palliata, 366.

puella, 367.
Cyphanta, 360.

arachnoides, 361.

circopora, 361.

colpodes, 361.

bispida, 362.

hystrix, 362.

kevis, 361.

CYPHINIDA, 359.
Cyphinidium, 371.

amphilophus, 370.

amphistylium, 371.

apicatum, 371.

coronatum, 372.
Cyphinoma, 369.
Cypbinura, 370.
Cyphinus, 369.

amphacanthus, 369.

amphilophus, 370.

dixiphos, 370.

penicillatus, 370.
Cyphocolpus, 368.

didymus, 368.

virginis, 369.
Cyphonium, 363.

diattus, 364.

ceratospyris, 366.

coscinoides, 363.

cribellum, 365.

ethmarium, 363.

facettarium, 365.

hexagonium, 364.

mammarium, 364.

profundum, 365.

trinacrium, 364.

virgineum, 363.
CYKTELLAKIA, 1015.
CYRTIDA, 1126.
Cyrtidosphsera, 65.

echinoides, 214.

reticulata, 66.
CYRTOCALPIDA, 1178.
Cyrtocalpis, 1185.

amphora, 1186.

cassis, 1301.

compacta, 1187.

gromia, 1188.

lithomitra, 1187.

obliqua, 1187.

ovulum, 1187.

reticulum, 1186.

sethopora, 1187.

urceolns, 1186.

urna, 1186.
Cyrtocapsa, 1512.

chrysalidium, 1515.

colatractus, 1414.

compacta, 1512.

cornuta, 1513.

costata, 1514.

diploconus, 1513.

fusulus, 1514.

incrassata, 1514.

inflata, 1513.

pyrum, 1513.

tetrapera, 1512.
Cyrtocapsella, 1512.
Cyrtocapsoma, 1514.

Cyrtocorys, 1457.
CYRTOIDEA, 1126.
Cyrtolagena, 1451.

laguncula, 1451.
Cyrtopera, 1450.

gasteroptera, 1451.

lagenella, 1451.

laguncula, 1451.

ornithoptera, 1450.

thoracoptera, 1450.
Cyrtophormis, 1459.

aculeata, 1461.

acutata, 1461.

armata, 1460.

cingulata, 1460.

cornuta, 1462.

corona, 1462.

cylindrica, 1461.

fimbriata, 1462.

ovata, 1460.

turricula, 1463.

turrita, 1462.
Cyrtophormiscus, 1460.
CjTrtophormium, 1460.
Cyrtostrobus, 1471.
Cystidium, 897.

inerme, 897.

lecythium, 897.

princeps, 897.
Cystophormis, 1165.

aerostatica, 1166.

pila, 1165.

spiralis, 1166.

tabulata, 1166.
CYTOPHOEA, 1.

Dendrocircus, 948.

arborescens, 949.

barbadeusis, 950.

dodecancistra, 949.

dodecarrhiza, 949.

elegans, 949.

quadrangulus, 948.

stalactites, 950.
Dendrospyris, 1038.

arborescens, 1040.

bibrachiata, 1039.

dirrhiza, 1039.

furcata, 1039.

polyrrhiza, 1039.

ramosa, 1040.

stylophora, 1038.
Dermatosphsera, 1763.
Desmartus, 398.

larval is, 398.

tubulatus, 399.
Desmocampe, 397.

aphrodite, 397.

atractus, 398.

catenula, 397.

REPORT ON THE RADIOLARIA.

1777

Desmocampe —

taenioides, 397.
DESMOCAMPIDA, 392.
Desmospyris, 1089.

anthocyrtoides, 1090.

carpocanium, 1090.

cyrtocolpos, 1090.

mammillata, 1089.
Dicolocapsa, 1312.

megacephala, 1312.

mierocephala, 1312.

platycephala, 1312.
Dicranastrum, 550.

antilope, 551.

bifurcatum, 552.

cornutum, 551.

dichotomum, 550.

furcatum, 550.

tricuspis, 551.

trifarium, 552.

wyyillei, 551.
Dictyastrella, 524.
Dictyastromma, 525.
Dictyastrura, 524.

aeuleatum, 526.

angulatuin, 524.

bandaicura, 525.

hexagoimm, 525.

lyra, 538.

laumorphum, 537.

triactis, 526.

trirrhopalum, 525.

trispinosum, 525.

velalum, 545.
Dictyaspis, 865.

compacta, 865.

favosa, 865.

solidissima, 865.
Didyatradus, 1361.

fenestratu-s, 1361.
Dictyocephalus, 1305.

amphora, 1305.

ampulla, 1308.

australis, 1306.

capita, 1309.

cavea, 1309.

crassiceps, 1306.

excellens, 1306.

galeatus, 1208.

globiceps, 1308.

hispidus, 1309.

larvatus, 1292.

mediterraneus, 1307.

obtusus, 1308.

ocellatus, 1306.

papillosus, 1307.

reticulum, 1307.

tabnlatus, 1307.

urceolus, 1305.
Dictyoceras, 1324.

(ZOOL. CHALL. EXP. — PART XL.-

Dictyoceras —

bombus, 1325.

formica, 1325.

insectum, 1324.

melitta, 1325.

virchowii, 1325.
Dictyoeha, 1557.

abnomiis, 1561.

abyssorum, 1559.

aculeata, 1565.

anacantha, 1565.

asteroides, 1564.

binoculus, 1565.

bipartita, 1563.

bisternaria, 1565,

corona, 1566.

crux, 1563.

cyrtoides, 1569.

diadema, 1567.

diommata, 1565.

elegans, 1564.

elliptica, 1556.

epiodon, 1561.

erebi, 1565.

fibula, 1561.

haliomtna, 1565.

hemisphcerica, 1569.

heptacanthus, 1568.

Jwxathyra, 1565.

medusa, 1560.

mesophthalma, 1563.

messanensis, 1561.

navicula, 1559.

octonaria, 1566.

omamentum, 1565.

pentasterias, 1564.

polyactis, 1566.

pens, 1559.

ponticulus, 1559.

quadrata, 1559.

quinaria, 1564.

rhombus, 1562.
, septenaria, 1566.

sinus, 1566.

speculum, 1565.

stapedia, 1561.

staurcKanthus, 1566.

staurodon, 1560.

Stella, 1565.

superstructa, 1568.

tenella, 1561.

triacantha, 1559.

triactis, 1559.

triangula, 1555.

trifenestrata, 1559.

trigona, 1764.

triommata, 1559.

tripyla, 1560.

ubera, 1565.
DICTYOCHIDA, 1554.

1887.)

Dictyocodon, 1334.

annasethe, 1334.

carolotse, 1335.

palladius, 1335.

prometheus, 1336.
Dictyocoryne, 592.

agrigentina, 593,

charybdaea, 593.

echinata, 594.

euchitonia, 592.

pentagona, 593.

profunda, 592.

tetradiscus, 592.

tetras, 597.

trigona, 593.
Dictyooryphalos, 1308.
Dictyomitra, 1476.

articulata, 1476.

conica, 1477.

costata, 1478.

demersissima, 1478.

ehrenbergii, 1422.

eurythorax, 1477.

lineata, 1484.

macilenta, 1476.

microcephala, 1477.

multicostata, 1478.

polypora, 1477.

punctata, 1486.

ventricosa, 1503.
Dictyomitrella, 1476.
Dictyomitrissa, 1477.
Dictyoniitroma, 1478.
Dictyophimium, 1195.
Dictyophimus, 1195.

arabicus, 1198.

bicornis, 1200.

brandtii, 1198.

biitschlii, 1201.

ehallengeri, 1196.

cienkowskii, 1200.

eortina, 1197.

craticula, 1196.

gracilipes, 1197.

hamosus, 1199.

hertwigii, 1201.

lasanum, 1197.

longipes, 1197.

lucerna, 1199.

platycephalus, 1198.

pleetaniscus, 1196.

pocillum, 1200.

pyramis, 1196.

sphserocephalus, 1195.

tridentatus, 1199.

tripus, 1195.

triserratus, 1200.
Dictyoplegma, W).

spongiosum, 90.
Dictyopodium, 1352.

Rr 223

1778

THE VOYAGE OF H.M.S. CHALLENGER.

Dictyopodium —

liwrne, 1332.

chalUngeri, 1231.

cothurnatum, 1353.

eucolpum, 1332.

eurylophus, 1352.

oxylophus, 1353.

scaphopodium, 1353.

thyrsolophus, 1351.

trilobum, 1333.
Dictyoprona, 1250.
Dictyoprora, 1305.
Dictyosoma, 90.

spongiosum, 90.

trigonizon, 1612.
Dictyospyrantha, 1073.
Dictyospyrella, 1074.
Dictyospyris, 1073.

anthophora, 1076.

biloba, 1074.

clathrata, 1049.

elathrus, 1049.

distoma, 1073.

enneastoma, 1077.

fenestra, 1075.

gigas, 1075.

hexastoma, 1077.

mammillaris, 1076.

messanensis, 1076.

polystoma, 1077.

quadriloba, 1076.

reticulata, 1096.

sphcera, 1400.

spinulosa, 1075.

stalactites, 1073.

tetrastoma, 1075.

tridentata, 1072.

triloba, 1074.

triomma, 1074.

tristoma, 1074.
Dictyospyrissa, 1075.
Dietyospyromma, 1076.
DICYKTIDA, 1192.
Didymocyrtis, 364.

ceratospyris, 366.

entomoccrra, 367.

hexagonia, 364.

faceta, 365.
Didymospyris, 367.

colpodes, 367.

entomocora, 367.
Dioniscus, 486.
Diplactinium, 470.
Diplactura, 469.

diplobraohia, 469.

diploconus, 470.
Diplacterium, 469.
DIPLOCONIDA, 881.
Diploconium, 886.
Diploconulus, 885.

Diploconus, 885.

amalla, 885.

cotyliscus, 886.

cyathiscus, 885.

cylindrus, 885.

fasces, 886.

hexaphyllus, 886.

saturuus, 886.
Diplocolpium, 887.
Diplocolpulus, 880.
Diplocolpus, 887.

costatus, 887.

cristatua, 887.

dentatus, 888.

serratus, 888.

sulcatus, 888.
Diplocyclas, 1392.

bicincta, 1393.

bicorona, 1392.

bizonalis, 1373.

DlPLOPHRACTA, 847.

Diplosphaera, 246.

dentieulata, 247.

dictyota, 247.

gracilis, 247.

hexagonalis, 246.

ornata, 246.

polygonalis, 247.

reticulata, 248.

spinosa, 245.

stellata, 251.

triglochin, 248.
DIPLOSPH.ERIDA, 230.

DlPLOZONAKIA, 640.

Dipoeoronis, 980.
Dipocubus, 993.
Diporasparium, 816.
DIPORASFIDA, 808.
Diporaspidium, 817.
Diporaspis, 816.

circopora, 816.

nephropora, 816.

zygopora, 817.
DIPOSPYRIDA, 1035.
Dipospyris, 1036.

bipes, 1036.

chelifer, 1037.

cubus, 1036.

forcipata, 1037.

irregularis, 1037.

mystax, 1036.

sigmopodium, 1037.
DISCIDA, 402.
DISCOIDEA, 402.

DlSCOPYLIDA, 571.

Discospira, 495.

accrescens, 499.
Ulix, 496.
deformis, 498.
duplex, 497.

aira —

helicoides, 496.

operculina, 496.

spiralis, 496.
DISCOSPIRIDA, 481.
Discopyle, 573.

elliptica, 573.

osculata, 573.
Discozonium, 571.

cyclonium, 571.

hexagon ium, 572.

trigonium, 572.
Disolenia, 113.
Distephanolithis, 970.
Distephanus, 1562.

aculeatus, 1565.

asteroides, 1564.

corona, 1566.

crux, 1563.

diadema, 1567.

mesophthalmus, 1563.

octogonius, 1567.

octonarius, 1566.

ornamentum, 1565.

pentasterias, 1564.

rotundus, 1565.

sinus, 1566.

speculum, 1565.

stauracanthus, 1564.
Distriactis, 436.

alternatus, 437.

amphithectus, 437.

corallanthus, 437.

lirianthus, 436.

paimanthus, 437.
Dizonium, 635.

amphacanthum, 636.

circulare, 635.

elliptieum, 635.

octacanthum, 636.

pleuracanthum, 636.

stauracanthum, 636.

transversum, 635.
Dodecaspis, 834.

tricinata, 834.

trizonia, 835.
Doracantha, 756.

dorataspis, 756.
Doratasparium, 813.

DORATASPIDA, 802.
Dorataspidium, 814.
Dorataspis, 813.

tipennis, 809.

cataphracta, 810.

costata, 812.

diodon, 837.

fusigera, 813.

gladiata, 815.

loricata, 814.

macracautha, 814.

REPORT ON THE RADIOLARIA.

1779

Dorataspis —

macropora, 814.

micropora, 815.

parmipora, 827.

polyancistra, 840.

polypora, 815.

typica, 815.

solidissima, 865.
Dorcadospyris, 1040.

antilope, 1041.

decussata, 1041.

dentata, 1040.

dinoceras, 1041.

lunulata, 1041.
Dorypelta, 857.

dodecaspis, 858.

furcata, 857.

gladiata, 857.

lithoptera, 858.

ramosa, 857.

stauroptera, 857.

tessaraspis, 858.

tetrodon, 857.
Dorypeltarium, 856.
Dorypeltidium, 857.
Dorypeltonium, 858.
Druppatractus, 324.

accipenser, 325.

belone, 325.

coronatus, 326.

diodon, 327.

hippocampus, 324.

ichthydium, 324.

lams, 327.

pisciculus, 328.

ostraeion, 326.

testudo, 325.

xiphias, 327.
Druppocarpus, 311.

ananassa, 311.

borassus, 312.

castanea, 311.

chamserops, 312.

corypha, 312.
Druppula, 308.

areca, 309.

caryota, 309.

cocos, 308.

drupa, 308.

elliptica, 310.

nucula, 310.

oliva, 310.

ovata, 309.

pandanus, 308.

phcenix, 308.

prunum, 310.
DRUPPULIDA, 306.
Drymosphfera, 248.

cladopliora, 249.

dendrophora, 249.

Drymosphsera —

furcata, 249.

hexagonalis, 248.

polygonalis, 249.
Drymospira, 694.
DYOPETJNIDA, 288.
DYOSPH.«IUDA, 52.
DYOSTEPHIDA, 932.
Dyscollosphsera, 96.
DYSTYMPANIDA, 1006.
Dystympanium, 1006.

dictyocha, 1007.

distephanus, 1007.

medusa, 1007.

Echinactura, 480.

asteriscus, 480.

culcita, 480.

goniaster, 480.
Echinaspis, 833.

diadema, 833.

dichotoma, 832.

echinoides, 833.
Eehinocalpis, 1170.
Echinocapsa, 1190.

EOHINOCYSTIDA, 1.

Echinomma, 257.

aculeatum, 258.

cidaris, 257.

diadema, 258.

echinidium, 257.

sphaerechiaus, 258.

toxopneustes, 259.

trinacrium, 258.
Echinosphcera, 638.

datura, 638.
ECTOLITHIA, Ixxii.
Elaphococcus, 227.

cervicornis, 228.

dichotoraus, 229.

drymodes, 229.

elaphoceras, 228.

furcatus, 228.

umbellatus, 229.

umbellifer, 228.
Elaphospyris, 1056.

alcicornis, 1057.

capricornis, 1056.

cervicornis, 1057.

damsecornis, 1057.

heptaceros, 1056.
Elatomma, 242.

irregulare, 243.

juniperinum, 243.

penicillus, 243.

pinetum, 242.

scoparium, 242.
ELLIPSIDA, 299.
Ellipsidium, 294.

artocarpus, 294.

Ellipsidium —

datura, 294.

echinidium, 295.

opuntia, 295.

pandanidium, 294.
Ellipse-stylus, 299.

aqnila, 300.

avicularis, 299.

ciconia, 300.

columba, 300.

gallinula, 301.

hirundo, 301.

megadictya, 801.

ornithoides, 299.

psittacus, 300.
Ellipsoxiphus, 296.

atractus, 298.

bipolaris, 287.

claviger, 297.

elegans, 296.

flosculus, 296.

fragilis, 296.

parvoforaminus, 297.

suessi, 297.
Ennealacorys, 1374.
Enneaphormis, 1246.

rotula, 1246.
Enneaplegma, 929.

emieacantha, 929.
Enneapleuris, 1257.
Entocannula, 1660.

circularis, 1661.

hirsuta, 1661.

infundibulum, 1661.

subglobosa, 1661.
ENTOLITHIA, Ixxii.
Ethmosphaera, 69.

conosiphonia, 69.

leptosiphonia, 70.

macrosiphonia, 70.

minuta, 1762.

pachysiphonia, 70.

polysiphonia, 70.

siphonophora, 69.

siphonophorites, 1762.

stenosiphonia, 70.

vulgaris, 1762.
ETHMOSPILERIDA, 61.
Eucecryphalium, 1221.
Eucecryphalus, 1220.

campanella, 1223.

corocalyptra, 1221.

cuvieri, 1222.

gegenbauri, 1222.

halicalyptra, 1221.

huxleyi, 1215.

laivis, 1213.

miilleri, 1222.

schultzei, 1216.
Euchitonia, 532.

1780

THE VOYAGE OF H.M.S. CHALLENGEE.

Euchitonia —

acuta, 536.
amcena, 1762.
beckmannii, 534.
carcinus, 535.
clathrata, 1762.
crevolensis, 1762.
cruciata, 533.
dubia, 1762.
echinata, 536.
elegaus, 535.
euclidis, 631.
furcata, 532.
gegenbauri, 439.
grandis, 1762.
leydigii, 530.
Tcoellikeri, 530.
krohnii, 539.
lanceolate, 434.
muelleri, 533.
muellerites, 1762.
stoehrii, 534.
triangulum, 533.
virchowii, 535.
ypsiloides, 536.
zittelii, 534.

EUCHITONIDA, 516.

Eucollosphaera, 95.
EUCORONIDA, 976.
Eucoronis, 976.

angnlata, 978.

arborescens, 978.

cervicornis, 978.

challengeri, 978.

Isevigata, 977.

nephrospyris, 977.

perspicillum, 977.

EUCYRTIDINA, 1127.

Eucyrtidium, 1487.

acanthocephalum, 1421.
acephalum, 1484.
acuminatum, 1488.
acutatum, 1461.
cegaium, 1400.
alauda, 1418.
amplum, 1402.
ampulla, 1251.
annulatum, 1481.
anomalum, 1492.
anthophorum, 1497.
antilope, 1404.
apiculatum, 1404.
aquilonare, 1504.
arclum, 1414.
argus, 1472.
armadillo, 1302.
annatum, 1495.
articulalum, 1476.
asperum, 1408.
attemiatum, 1417.

Eucyrtidium —

auritum, 1482.
awstrale, 1487.
barbadense, 1406.
biauritum, 1411.
bicorne, 1421.
biitschlii, 1492.
campanulatum, 1400.
cancrinum, 1299.
carinatum, 1316.
cassis, 1424.
ceruits, 1292.
chrysalidium, 1490.
cienkowskii, 1493.
compactum, 1512.
conostoma, 1495.
cornutella, 1473. '
coronatum, 1411.
cranoides, 1322.
crassiceps, 1306.
cretieum, 1415.
cryptocephalum, 1426.
cryptoprora, 1423.
cuspidatum, 1473.
cylindricum, 1406.
damsianwm, 1437.
demersissimum, 1478.
diaphanum, 1505.
doliolum, 1489.
ehrenbergii, 1495.
elegans, 1406.
elongatum, 1493.
embolum, 1369.
eruca, 1493.
eupomm, 1502.
excellens, 1306.
fastosum, 1369.
^CTW, 1403.
fatuligerum, 1498.
fusiforme, 1489.
galathese, 1492.
galea, 1492.
gemmaium, 1425.
gracile, 1295.
hertwigii, 1491.
Tieteroporum, 1506.
hexagonatum, 1489.
/iiZJ<%, 1402.
hispidum, 1506.
hyperboreum, 1486.
imbricatum, 1483.
incrassalum, 1514.
increscent, 1506.
infraculcalum, 1519.
lagena, 1491.
lagenoides, 1498.
lineatum, 1484.
macilentum, 1476.
megaloporum, 1425.
microcephalum, 1477.

Eucyrtidium —

microporum, 1474.

microlheca, 1407.

mongolfieri, 1251.

montiparum, 1493.

multiseriatum, 1505.

nossa, 1293.

nereidum, 1502.

nucula, 1423.

obstiptim, 1484.

ocellatum, 1306.

ovatum, 1495.

pachyderms, 1483.

papillosum, 1307.

pauperum, 1482.

picus, 1472.

pirum, 1423.

platycephalum, 1502.

pleuracanthum, 1300.

profundissimum, 1480.

punctatum, 1486.

pupa, 1412.

pusillum, 1406.

quadrarticulatum, 1504.

raphanus, 1498.

reticulum, 1307.

scalarium, 1484.

scolopax, 1416.

seriolatum, 1486.

sijo^o, 1497.

spheerophilum, 1418.

spinosum, 1490.

stephanophorum, 1410.

stohrii, 1494.

subacutum, 1300.

teuscheri, 1491.

tornatum, 1473.

trachelium, 1405.

tricinctum, 1464.

trochus, 1280.

tropezianum, 1488.

tumidulum, 1506.

turgidulum, 1415.

versipellis, 1425.

zandeum, 1399.

zanguebaricum, 1400.
Eucyrtis, 1488.
Eucyrtomphalus, 1221.
Euphysetta, 1670.

amphieodon, 1670.

hybocodon, 1670.

stauroeodon, 1670.

EUPHYSETTIDA, 1666.

Euscenarium, 1146.
Euscenidium, 1147.
Euscenium, 1146.

archicyrtis, 1146.

furcatum, 1147.

hemisphaericum, 1147.

plectaniscus, 1146.

REPORT ON THE RADIOLARIA.

1781

Euscenium —

quadratum, 1148.

ramosum, 1148.

tricolpium, 1147.

tripospyris, 1147.
Eusyringium, 1496.

cannostoma, 1499.

conosiphon, 1496.

fistuligerum, 1498.

lagenoicles, 1498.

leptosiphon, 1497.

macrosiphon, 1487.

pachysiphon, 1496.

rhaphanus, 1498.

sipho, 1497.

siphonostoma, 1499.
ElTTYMPANIDA, 1007.
Eutympanium, 1013.

coronarium, 1014.

dodecarium, 1014.

militare, 1014.

musicantum, 1013.

octonarium, 1014.

Flustrdla, 492.

bilobata, 527.
concentrica, 492.
cyclia, 494.
haliomma, 692.
macropora, 493.
micromma, 1761.
spiralis, 496.

Gamospyris, 1042.

annulus, 1042.

circulus, 1042.
Gazelletta, 1670.

bifurca, 1672.

cyrtonema, 1671.

dendronema, 1674.

furcata, 1672.

hexanema, 1671.

macronema, 1671.

melusina, 1674.

orthonema, 1671.

pectinata, 1672.

penicillata, 1672.

pinnata, 1672.

robusta, 1673.

schleinitzii, 1673.

studeri, 1673.

trispathilla, 1673.
GAZELLETTIDA, 1666.
Giraffospyris, 1056.

Twptaceros, 1076.
Gorgonetta, 1675.

bisenaria, 1675.

carmarina, 1675.

geryonia, 1675.

mirabilis, 1674.

Gorgospyris, 1069.

ehrenbergii, 1070.

eurycolpos, 1071.

lamellosa, 1071.

liriope, 1071.

medusa, 1070.

medusetta, 1070.

polypus, 1070.

schizopodia, 1071.

thamnopodia, 1071.
Gorgospyrium, 1070.

Haeckeliana, 1702.

darwiniana, 1702.

goetheana, 1702.

maxima, 1701.

lamarckiana, 1701.

murrayana, 1702.

porcellana, 1701.
HAECKELINIDA, 1700.
Hagiastrum, 542.

bramae, 543.

buddhffi, 542.

christi, 543.

cornutum, 551.

mohammedis, 543.

mosis, 543.

rhopalophorum, 541.
Halicapsa, 1189.

hystrix, 1191.

lithapium, 1190.

papillata, 1190.

prunoides, 1190.

pyriforniis, 1191.

triglochin, 1190.
Halicalyptra, 1168.

ampulla, 1169.

campanula, 1169.

cancellata, 1167.

castanella, 1170.

cornuta, 1398.

fimbriata, 1387.

galca, 1136.

novena, 1169.

orci, 1397.

petalospyris, 1169.

setosci, 1280.

spinosa, 1170.

virginica, 1169.
HALICALYPTRINA, 1127.
Haliomma, 230.

amphiaspis, 1761.

amphidiscus, 447.

amphisiphon, 374.

antarcticum, 238.

apertum, 159.

apictilatum, 73.

arachnium, 230.

asperum, 344.

asteracanthion, 196.

Haliomma —

beroes, 238.
boreale, 237.
capense, 235.
capillaceum, 236.
castanea, 232.
cenosptuxra, 291.
circumtextum, 233.
clavatum, 239.
compactum, 239.
contiguum, 439.
crenatum, 314.
datura, 232.
denticulatum, 235.
didymocyrtis, 366.
didymum, 367.
dixyphos, 135.
duodecinum, 233.
echinaster, 240.
echinmdes, 842.
ellipticum, 310.
enneaxiphos, 234.
entactinia, 74.
erinaceum, 236.
favosum, 231.
gracile, 1761.
grande, 235.
helianthus, 446.
hexacanthum, 184.
hexagonium, 230.
hexagonum, 138.
hispidmn, 136.
horridum, 232.
humboldtii, 449.
hystrix, 854.
inerme, 80.
inftmdibuliforme, 72.
lagena, 527.
lens, 1761.
ligurinum, 1764.
lirianthus, 232.
longispinum, 235.
macrodoras, 238.
mediisa, 80.
megaporum, 233.
melitomina, 231.
modestum, 74.
nitidum, 1761.
obltmgum, 1761.
octacanthum, 442.
oculatum, 234.
ovatum, 309.
patagonicum, 239.
permagnum, 239.
perspicuum, 162.
phacodiscus, 447.
polyacanthum, 350.
pyriforme, 1191.
quadruplex, 262.
radians, 423.

1782

THE VOYAGE OF H.M.S. CHALLENGER.

Haliomma —

radiatum, 423.

radicatum, 1051.

regulare, 231.

rhodococcus, 237.

scutum, 1761.

sexaculcatum, 186.

sol, 446.

spinulosum, 237.

tabulation, 871.

tenellum, 236.

tenuispinum, 234.

tetracanthum, 164.

triactis, 432.

trinacrium, 254.

triplex, 314.

umbonatum, 449.

mrginicum, 1169.

wyvillei, 238.
Haliommantha, 230.
HALIOMMATIDA, 230.
Saliommatidium, 842.

echinoides, 842.

fenestratum, 869.

ligurinum, 1764.

mulleri, 871.

tetragonopum, 845.
HALIOMMATINA, 51.
Haliommetta, 233.
HALIOMMIDA, 230.
Haliomrailla, 236.
Haliommura, 237.
Haliphormis, 1166.

costata, 1167.

lagena, 1167.
HAPLOPHRACTA, 847.
HAPLOZONARIA, 632.
Heliocladus, 451.

dendrophorus, 451.

furcatus, 451.
Heliodendrum, 452.
HELIODISCIDA, 444.
Heliodiscus, 444.

amphidiscus, 447.

apollinis, 450.

asteriscus, 445.

cingillum, 448.

echiniscus, 448.

glyphodon, 446.

grottensc, 451.

helianthus, 446.

humboldti, 449.

marginatus, 449.

medusinus, 438.

pertusus, 448.

phacodiscus, 447.

polymorphus, 447.

siculus, 446.

simplex, 1762.

sol, 446.

Heliodiscus —

solaster, 447.

sulcatus, 449.

trigonodon, 445.

trochiscus, 445.

umbonatus, 449.

zoroaster, 450.
Heliodrymus, 450.

dendrocyclus, 451.

furcatus, 451.

grottensis, 451.

setosus, 452.

ramosus, 452.

viminalis, 452.
HELIOSESTRIDA, 427.
Heliosestrum, 438.

aegineta, 440.

contiguum, 439.

craspedotum, 441.

glyphodon, 446.

irregulare, 440.

liriope, 439.

medusinum, 438.

octagonium, 441.

octangulum, 441.

octastrum, 438.

octonum, 440.

quadrigerainum, 439.

solarium, 439.
Heliosoma, 240.

duodecilla, 241.

echinaster, 240.

elegans, 240.

hastatum, 241.

indicum, 241.

radians, 240.
Heliosphaera, 217.

actinota, 218.

castenella, 219.

coronata, 219.

cristata, 219.

echinoides, 218.

echinoidites, 1762.

elector, 220.

elegans, 218.

floribunda, 219.

heteracantha, 220.

hexagonaria, 217.

hyperionis, 220.

inerftiis, 62.

insignia, 212.

pectinata, 218.

polygonaria, 220.

Solaris, 221.

tenuissima, 210.
HELIOSPH^RIDA, 209.
Heliostaurus, 434.

cruciatus, 434.
Heliostylus, 429.

dentalus, 429.

Heliostylus —

serratus, 429.
Hcptaplegma, 929.

heptamntha, 929.
HEXACARYIDA, 202.
Hexacarymn, 203.

arboresceus, 203.
Hexacolparium, 880.
Hexacolpidium, 880.
Hexacolpus, 880.

conifer, 880.

dodecotus, 881.

iufundibulum, 881.

nivalis, 880.

trypanon, 881.
Hexaconarium, 876.
Hexaconidium, 877.
Hexacontarium, 200.

dentatum, 200.

clavatum, 200.
HEXACONTIDA, 191.
Hexacontium, 192.

antarcticum, 197.

asteracanthion, 196.

axophsenum, 196.

axotrias, 192.

circumtextum, 193.

clavigerum, 195.

dry modes, 198.

favosum, 194.

floridum, 195.

furcatum, 198.

gladiatum, 198.

hexaconicum, 196.

hexactis, 192.

hexagonale, 194.

Isevigatum, 193.

octahedrum, 193.

papillosum, 197.

periplectum, 199.

phfenaxonium, 192.

polygonale, 197.

prionacanthum, 195.

sceptrum, 194.

setosum, 198.

triplosphserium, 193.
Hexaconus, 876.

ciliatus, 876.

coronatus, 877.

echinatus, 878.

serratus, 877.

vaginatus, 877.

velatus, 877.
Hexacorethra, 1048.

inagica, 1048.
Hexacoronis, 981.
Hexaeromidium, 202.

arachnoides, 202.
HEXACROMTIDA, 201.
Hexacromyum, 201.

REPORT ON THE RADIOLARIA.

1783

Hexacromyum —

arachnoides, 202.

cubaxonium, 303.

elegans, 201.

octahedrum, 202.

quadrigatum, 201.
Hexactura, 560.

orchidacea, 560.
Hexadendron, 199.

bipinnatum, 200.

quadricuspis, 199.
Hexadoras, 205.

axophsena, 205.

lychnosphsera, 205.

ootahedrum, 205.
HEXADORIDA, 205.
Hexadoridium, 206.

streptacanthum, 206.
Hexalacorys, 1372.
Hexalasparium, 874.
HEXALASPIDA, 872.
Hexalaspidium, 875.
Hexalaspis, 874.

heliodiscus, 875.

hexaglypha, 876.

hexalastrum, 875.

nivalis, 880.

sexalata, 875.

stellata, 875.
Hexalastrum, 559.

crinanthum, 559.

geryonidum, 560.

orcbidaceum, 560.

palmanthum, 559.
Hexalatractus, 1393.

fusiformis, 1394.

sexalatus, 1394.
Hexaloncbarium, 190.

hystricinum, 191.

oetabedrum, 190.

pbilosophicum, 190.
Hexalonche, 179.

amphisiphon, 182.

anaximandri, 182.

anaximenis, 183.

aristarchi, 185.

aspera, 184.

brevicornis, 181.

castanella, 184.

conicornis, 181.

cristata, 183.

curvicornis, 181.

ekphautsea, 185.

favosa, 180.

geometrica, 184.

grandis, 182.

heracliti, 187.

hexacantha, 184.

hystricina, 187.

ootahedra, 181.

Hexalonche —

octoeolpa, 183.

phsenaxonia, 180.

philosophica, 186

pythagorsea, 185.

rosetta, 180.

seleuci, 186.

serrata, 183.

setosa, 187.

sexaculeata, 186.

xenophanis, 187.
HEXALONCHIDA, 179.
Hexalonehidium, 191.

axonometrum, 191.
Hexancistra, 188.

ancorata, 188.

mirabilis, 189.

quadricuspis, 189.

tricuspis, 188.

triserrata, 188.
Hexapilys, 189.

mirabilis, 189.
Hexaplagia, 915.

antarctica, 915.

arctica, 915.

australis, 916.

collaris, 916
HEXAPLAGIDA, 915.
Hexaplecta, 927.

triaxonia, 927.

tricladonia, 927.
HEXAPLECTIDA, 927.
Hexapleuris, 1257.
HEXAPTLIDA, 567.
Hexapyle, 568.

circularis, 569.

dodecantha, 569.

hexacantha, 569.

polyacantha, 570.

sexangula, 568.

triacantba, 569.

triangula, 568.
HEXASPTRIDA, 1046.
Hexaspyridium, 1047.
Hexaspyris, 1046.

alterna, 1047.

articulata, 1048.

butscblii, 1047.

hexacorctbra, 1048

ophirensis, 1048.

setigera, 1047.

spinosa, 1048.
Hexastylarium, 177.

elongatum, 178.

heteraxonium, 177.

quadratum, 178.
HEXASTYLIDA, 171.
Hexastylidium, 178.

rhomboides, 178.
spirale, 179.

Hexastylus, 171.

biantis, 172.

brevispinus, 175.

cbilonis, 174.

cleobuli, 174.

cochleatus, 174.

conifer, 176.

contortus, 177.

dimensivus, 175.

dictyotus, 176.

favosus, 172.

hirsutus, 176.

longispinus, 175.

longissimus, 172.

marginatus, 176.

maximus, 173.

minimus, 172.

periandri, 173.

pbaenaxonius, 171.

pittaci, 173.

sapientum, 171.

setosus, 174.

solonis, 173.

spiralis, 177.

thaletis, 172.

triaxonius, 175.
Hexinastrum, 560.

geryonidum, 560.
Hexonasparium, 878.
Hexonaspidium, 879.
Hexonaspis, 879.

hastata, 879.

heliosestrum, 878.

hexagona, 879.

hexapleura, 879.
Hexoniscus, 488.
Histiastrum, 544.

boseanum, 546.

brunonis, 548.

circulare, 546.

corona turn, 546.

democriti, 548.

excisum, 544.
fasciatum, 535.

gladiatum, 545.

lurimunse, 1762.

pentadiscus, 546.

quadrigatum, 544.

quaternarium, 545.

straussii, 547.

ternarium, 531.

trinacrium, 530.

velatum, 545.

ypsiloides, 536.
Holosiphonia, 104.

HOLOTRYPASTA, 5.

Hylaspis, 846.

barbata, 847.
coronata, 847.
serrulata, 846.

1784

THE VOYAGE OF H.M.S. CHALLENGER.

Hymenactura, 473.

archimedis, 473.

copernici, 475.

hexagona, 474.

ptolomaei, 475.

pythagorae, 474.

trigona, 474.
Hymenactinium, 475.
Hymenacturium, 474.
Hymenastrella, 530.
Hymenastromma, 531.
Hymeniastrum, 530.

archimedis, 531.

euclidis, 531.

giimbelii, 530.

koellikeri, 530.

leydigii, 530.

pythagorae, 531.

ternarium, 531.

trigonarium, 532.
Hystrichasparium, 822.
Hystrichaspidium, 823.
Hystrichaspis, 822.

armata, 824.

cristata, 823.

divaricata, 824.

dorsata, 823.

foveolata, 824.

fruticata, 825.

furcata, 822.

pectinata, 822.

serrata, 825.

sulcata, 824.

ICOSAOANTHA, 717.

Icosasparium, 843.
Icosaspidium, 845.
Icosaspis, 844.

cruciata, 844.

elegans, 844.

icosahedra, 845.

icosastaura, 846.

multiforis, 845.

ornata, 844.

spectabilis, 845.

tabulate, 843.

tetragonopa, 845.

Lampoxanthium, 36.

brevispiculum, 36.

octoceras, 37.

pandora, 38.

punctatum, 37.

tetractinium, 37.
Lamprocyelas, 1390.

segles, 1391.

bajaderse, 1392.

deflorata, 1391.

maritalis, 1390.

nuptialis, 1390.

Lamprocyelas —

regime, 1391.

saltatricis, 1391.
Lamprocyclia, 1390.
Lamprocycloma, 1392.
Lamprodiscus, 1212.

coscinodiscus, 1213.

hevis, 1214.

monoccros, 1213.

tricostatus, 1213.
Lampromitra, 1214.

arborescens, 1216.

coronata, 1214.

dendrocorona, 1216.

furcata, 1215.

huxleyi, 1215.

pyramidalis, 1215.

quadricuspis, 1214.

schultzei, 1216.
LAMPROSPTRIDA, 1092.
Lamprospyris, 1093.

darwinii, 1094.

hookeri, 1094.

huxleyi, 1094.

lyelli, 1094.

spenceri, 1095.
Lamprotripus, 1199.

harrulus, 1201.

spinosus, 1201.

squarrosus, 1200.
Lampterium, 1376.
Lamptidium, 1377.
Lamptonium, 1378.
LARCAKIDA, 605.
Larcarium, 608.

amphistylum, 608.

axostylum, 609.

chsetostylum, 609.

hexastylum, 608.

octostylum, 609.

polystylum, 609.

staurostylum, 608.
Larcidium, 611.

axacanthum, 611.

dissacanthum, 611.

dodecanthum, 612.

hexacanthum, 611.

octacanthum, 612.

polyacantlium, 612.
LARCOIDEA, 599.
Larcospira, 696.

lentelliptica, 696.

oliva, 697.

quadrangula, 696.

sexangula, 696.
Larcospirema, 696.
LARCOSPIRIDA, 695.
Larcospironium, 697.
LARNACALPIDA, 619.
Larnacalpis, 620.

Larnacalpis —

lentellipsis, 620.

macrococcus, 621.

phacodiscus, 620.

subsphserica, 621.

triaxonia, 621.
Larnacantha, 621.

bicruciata, 623.

cladacantha, 623.

decacantha, 624.

dissacantha, 622.

dodecantha, 624.

drymacautha, 624.

hexacantha, 622.

octacantha, 623.

prismatica, 623.

quadricornis, 622.

stauracantha, 622.
LARNACIDA, 614.
Larnacidium, 618.

hexabelonium, 619.

polybelonium, 619.

staurobelonium, 619.
Larnacilla, 617.

medullaris, 618.

prometor, 618.

subglobosa, 618.

typus, 617.
LARNACILLIDA, 617.
Larnacoina, 625.

hexagonium, 625.

lentellipticum, 625.

quadruplex, 625.
Larnacospongus, 626.

larnacillifer, 626.

tetrapylifer, 626.
Larnacostupa, 627.

dendrophora, 627.

octacantha, 627.

spinosa, 627.
Leptarachnium, 1248.

aurelia, 1248.
Leptosphaera, 244.

ciliata, 245.

hexagonalis, 244.

polygonalis, 245.

reticulum, 246.

serrata, 245.

spinosa, 245.

stellata, 245.
Liosphoera, 76.

hexagonia, 76.

peridrominm, 77.

polypora, 78.

porulosa, 77.

rhodococcus, 77.
LIOSPH.SRIDA, 59.
Liriospyris, 1049.

amphithecta, 1050.

clathrata, 1049.

REPORT ON THE RADIOLARIA.

1785

Liriospyris—

heteropoda, 1050.

hexapoda, 3049.

turrita, 1050.
Lithapium, 303.

halicapsa, 303.

monooyrtis, 304.

pyriforme, 303.
Litharachnium, 1163.

arachnodiscus, 1164.

araneosum, 1163.

discoides, 1164.

epeira, 1164.

pilidium, 1164.

quadratella, 1254.

tentorium, 1163.
Lithatractus, 319.

carduelis, 321.

cirsium, 321.

conifer, 322.

conostylus, 323.

convallaria, 320.

echiniscus, 321.

fragilis, 319.

gamoporus, 323.

hexagonalis, 319.

jugatus, 323.

leptostylus, 320.

lobatus, 322.

pachystylus, 320.

rosetta, 322.
LlTHELIDA, 688.

Lithelius, 693.

alveoliua, 694.
arborescens, 695.
oapreolus, 694.
primordialis, 694.
Solaris, 695.
spiralis, 693.

LlTHOBOTRYIDA, 1111.

Lithobotrys, 1117.

adspersa, 1116.

biceps, 1113.

borealis, 1116.

cribrosa, 1113.

denticulata, 1013.

galea, 1123.

geminata, 1118.

inftata, 1123.

lithocorythium, 1118.

mascula, 1119.

nasuta, 1118.

nucula, 1116.

orchidea, 1119.

omata, 1118.

quadriloba, 1109.

sphcerothorax, 1119.

stiligera, 1088.

triloba, 1108.
Lithocampe, 1501.

(ZOOL. CHALL. EXP. PART XL. 1887.)

Lithocampe —

acuminata, 1488.
ampullaeea, 1402.
anomala, 1442.
aquilonaris, 1504.
arcta, 1414.
auricula, 1482.
aurita, 1482.
australis, 1487.
clava, 1507.
compressa, 1516.
corbula, 1761.
diaphana, 1505.
diploconus, 1505.
eminent, 1487.
eupora, 1502.
fimbriata, 1462.
fusiformis, 1503.
galea, 1492.
heteropora, 1506.
hexacola, 1507.
heptacola, 1506.
hirundo, 1356.
hispida, 1506.
hyperborea, 1486.
increscens, 1506.
lagena, 1491.
lineata, 1484.
meta, 1507.
multiseriata, 1505.
nereidum, 1502.
octocola, 1505.
ovata, 1504.
platycephala, 1502.
polycola, 1508.
punclata, 1486.
quadrarticulata, 1504.
radicula, 1503.
seriolata, 1486.
simtosa, 1761.
solitaria, 1281.
subligata, 1518.
tropeziana, 1488.
tumidula, 1506.
urceolata, 1507.
ventricosa, 1503.

LlTHOCAMPIDA, 1467.

Lithocampium, 1504.

eurythorax, 1474.
Lithocampula, 1502.
Lilhodftrpium, 1172.

pyriforme, 1172.
Lithochytridium, 1363.

LlTHOCHYTRINA, 1127.

Lithochytris, 1362.

barbadensis, 1289.
cortina, 1362.
galeata, 1363.
lanterna, 1364.
lucerna, 1384.

Lithochytris —

pileata, 1363.

pteropus, 1364.

pyramidalis, 1364.

pyriformis, 1362.

triangula, 1240.

tripodium, 1363.

vespertilio, 1365.
Lithochytrodes, 1362.
LITHOCIRCIDA, 940.
Lithocircus, 943.

annularis, 943.

annulus, 1761.

crambessa, 944.

decimalis, 944.

furcatus, 945.

haeckelii, 1762.

hexablastus, 944.

magnificus, 945.

mesocena, 132.

productus, 948.

quadricornis, 944.

rhombus, 1762.

tarandus, 944.

triangularis, 1555.

truncatus, 1762.

vinculatus, 975.
Lithocoronis, 978.

challengeri, 978.
Lithocorythium, 1117.

cephalodes, 978.

galea, 1123.

oxylophus, 1118.

platylophus, 1118.
Lithocubus, 1011.

astragalus, 1012.

geometricus, 1011.

octacanthus, 1011.

vinculatus, 1012.
Lithocyelia, 459.

cingulata, 459.

heteropora, 460.

lenticula, 459.

monococcus, 460.

ocellus, 460.

reticulata, 1761.

Stella, 467.

LlTHOOYCLIDA, 459.
LlTHOCYCLIDINA, 455.

Lithogromia, 1647.

diatomacea, 1647.
lenticula, 1647.
silicea, 1647.

LlTHOGROMIDA, 1647.

Litholopharium, 735.

LlTHOLOPHIDA, 733.

Litholophidium, 735.
Litholophonium, 736.
Litholophus, 734.

decapristis, 735.

Kr224

1786

THE VOYAGE OF H.M.S. CHALLENGER.

Litholophus —

decastylus, 735.

decimalis, 735.

fasciculus, 736.

lignrinus, 736.

penicillus, 736.

pyramidalis, 735.

rhipidium, 736.
Lithomelissa, 1203.

amphora, 1205.

bicornis, 1206.

biitschlii, 1207.

capita, 1257.

corythium, 1207.

decacantha, 1208.

ehrenbergii, 1204.

falcifera, 1207.

haeckelii, 1207.

hertwigii, 1207.

macroeeros, 1204.

maeroptera, 1204.

mediterranea, 1206.

microptera, 1236.

microstoma, 1205.

mitra, 1204.

pycnoptera, 1205.

spongiosa, 1210.

thoranites, 1206.

ventricosa, 1236.
Lithomespilus, 301.

alauda, 128.

flammabundus, 303.

flammeus, 302.

phloginus, 302.

phlogoides, 302.

pints, 129.

trogon, 129.
Lithomitra, 1483.

acephala, 1484.

australis, 1487.

chrysalis, 1485.

costata, 1485.

cylindrica, 1485.

eminens, 1487.

eruca, 1485.

hyperborea, 1486.

infundibulum, 1487.

lineata, 1484.

nodosaria, 1484,
pachyderma, 1482.
punctata, 1486.

seriolata, I486.
Lithomitrella, 1483.
Lithomitrissa, 1485.
Lithopera, 1233.

aniblystauros, 1311.
ananassa, 1234.
bacca, 1233.
bursella, 1234.
denticulala, 1073.

Lithopera —

elongate, 1762.

globosa, 1234.

gutta, 1234.

lagena, 1233.

nidus, 1311.

Oceania, 1232.

ovata, 1762.

oxystauros, 1311.

pyrum, 1232.

setosa, 1276.
Lithophyllium, 753.

condylatum, 754.

cruciatum, 754.

foliosum, 754.

gladiatum, 754.
Lithoptera, 778.

darwinii, 781.

dodecaptera, 780.

fenestrata, 781.

icosaptera, 781.

lamarckii, 779.

mulleri, 779.

quadrata, 780.

tetragona, 780.

tetraptera, 779.
Lithopteranna, 779.
Lithopterella, 780.

LlTHOPTERIDA, 776.

Lithopteroma, 780.
Lithornithium, 1354.

ciconia, 1354.

dictyoceras, 1325.

falco, 1355.

foveolatum, 1355.

fringilla, 1355.

hiruudo, 1356.

loxia, 1452.

luscinia, 1358.

trochilus, 1355.
Lithospira, 693.
Lithostrobus, 1468.

acuminatus, 1472.

argus, 1472.

botryocyrtis, 1475.

caloceras, 1471.

conulas, 1472.

cornutus, 1474.

cornutella, 1473.

cuspidatus, 1473.

cyrtoceras, 1470.

distichus, 1469.

hexagonalis, 1475.

hexastichus, 1470.

leptoceras, 1471.

lithobotrys, 1475.

macroceras, 1471.

microporus, 1474.

monostichus, 1469.
pentastichus, 1470.

Lithostrobus —

picus, 1472.

quadratus, 1474.

seriatus, 1474.

tetrastichus, 1470.

tornatus, 1473.

tristichus, 1469.
Lithotyinpanum, 1006.

spinosum, 1006.

tuberosum, 1006.
Lonchostaurus, 772.

bifidus, 773.

bifurcus, 773.

crystallinus, 773.

lanceolatus, 773.

rhombicus, 773.

rhomboides, 772.
Lophoconus, 1403.

antilope, 1404.

apiculatus, 1404.

cervus, 1405.

cornutella, 1404.

hexagonalis, 1404.

rhinoceros, 1405.
Lophocorys, 1420.

acanthocephala, 1421.

astrocephala, 1421.

bicornis, 1421.

brevicornis, 1422.

quadricornis, 1422.
Lophocyrtis, 1410.

biaurita, 1411.

coronata, 1411.

holothuria, 1410.

stephanophora, 1410.

synapta, 1411.
Lophophfena, 1303.

amphora, 1302.

apiculata, 1303.

capita, 1204.

circumtexta, 1304.

cornuta, 1398.

echinocephala, 1304.

galea, 1303.

galeata, 1204.

larvata, 1282.

liothorax, 1304.

lynx, 1303.

obtusa, 1308.

radians, 1303.
Lophophienoma, 1304.
Lophophsenula, 1303.
LOPHOSPTRIDA, 1078.
Lophospyris, 1066.

acuminata, 1080.

comosa, 1071.

dipodiscus, 1080.
Lyclmasparium, 839.
LYOHNASPIDA, 835.
Lychnaspidium, 842.

REPORT ON THE RADIOLARIA.

1787

Lychnaspidium —

haliommidium, 842.
Lychnaspis, 829.

oapillaris, 839.

cataplasta, 843.

echinoides, 842.

giltschii, 839.

haliommidium, 842.

longissima, 841.

maxima, 839.

minima, 841.

polyancistra, 840.

rabbeana, 842.

rottenburgii, 841.

serrata, 840.

undulata, 841.

wagenschieberi, 840.
Lychnocaaella, 1224.
Lychnocauissa, 1225.
Lychnocanium, 1224.

arabicum, 1198.

campanella, 1331.

carinatum, 1226.

clavigerum, 1230.

continuum, 1225.

crassipes, 1280.

cypselus, 1229.

dcpressum, 1331.

falciferum, 1207.

favosum, 1225.

fenestratum, 1228.

fortipes, 1227.

hamosum, 1199.

hirundo, 1227.

lanterna, 1224.

lucerna, 1199.

nodosum, 1225.

ovatum, 1229.

prcetextum, 1330.

pudicum, 1230.

pyriforme, 1225.

sigmopodium, 1228.

tetrapodium, 1228.

tribulus, 1226.

trichopus, 1228.

tridentatum, 1199.

tripodium, 1229.

tuberosum, 1227.

turgidum, 1319.

ventricosum, 1226.
Lychnocanoma, 1229.
Lychnodiotyum, 1230.

challengeri, 1231.

sethopodium, 1231.
scaphopodium, 1231.

wyvillei, 1231.
Lychnosphsera, 276.

regina, 277.
rhizoplegma, 276.

Mazosphsera, 108.
apicata, 109.
hippotis, 108.
inflala, 101.
Isevis, 109.
kgotia, 108.
Medusetta, 1667.

codonium, 1668.
craspedota, 1669.
minima, 1668.
quadrigata, 1668.
spiralis, 1669.
tetranema, 1669.
tiara, 1668.
MEDUSETTIDA, 1663.
Melitomma, 76.

formosum, 231.
melittosphaera, 73.
Melittosphsera, 72.
Merosiphonia, 106.
MEROTKYPASTA, 5.
Mesocena, 1554.

annulus, 1555.

binonaria, 1557.

bisoctona, 1557.

circulus, 1555.

crenulata, 1555.

diodon, 1555.

elliptica, 1556.

heplagona, 1557.

hexagona, 1556.

nonaria, 1557.

octogona, 1557.

octoradiata, 1557.

pentagona, 1556.

quadrangula, 1556.

quaternaria, 1556.

senaria, 1556.

septenaria, 1556.

stellata, 1557.

triangula, 1555.
Microcubus, 997.

amphispyris, 999.

cornutus, 999.

dodecastoma, 998.

pentacircus, 998.

quadrupes, 998.

zonarius, 998.
Micromelissa, 1205.

apis, 1235.

bombus, 1235.

microptera, 1236.

ventricosa, 1236.

vespa, 1235.
Mitrocalpis, 1188.

palliata, 1188.

MONOCYRTIDA, 1133.
MONODICTYA, 1126.

IIONOPRUNIDA, 288.
MONOPYLARIA, 889.

MONOPYLEA, 889.
MONOSPH^RIDA, 52.
MONOSTEPHIDA, 937.

Monostephus, 940.
Monozonium, 633.

alatum, 633.

amphistylum, 634.

hartingii, 1763.

pleurostylum, 634.

primordiale, 633.

staurostylum, 634.
Myelastrella, 553.
Myelastromma, 553.
Myelastrum, 553.

anomalum, 556.

ciliatum, 555.

decaoeros, 554.

dodecaceros, 554.

farfalla, 554.

giganteum, 555.

heteropterum, 553.

lobatum, 555.

medullare, 553.

octocorne, 553.

papilio, 554.

rotula, 555.

spinale, 553.
Myxobrachia, 22.

cienkowskii, 1763.

pluteus, 22.
rhopalum, 22.

Nassella, 898.

nassiterna, 898.

thalassicolla, 898.
NASSELLARIA, 889.
NASSELLIDA, 896.
NASSOIDEA, 895.
Nephrodictyum, 1101.
NEPHROSPYRIDA, 1099.
Nephrospyris, 1100.

cordata, 11C2.

nephridium, 1101.

paradictyum, 1102.

paradoxa, 1102.

phaseolus, 1101.

renilla, 1101.

Octalacorys, 1373.
Octodendron, 279.

araucaria, 280.

arboretum, 281.

contortum, 281.

cubocentron, 279.

pinetum, 280.

spathillatum, 280.

spirale, 279.

verticillatum, 281.
Octopelta, 855.

cultella, 855.

1788

THE VOYAGE OF H.M.S. CHALLENGER.

Octopelta —

furcella, 856.
scutella, 856.
Octophormis, 1245.
Octopyle, 650.

araphistyle, 651.
decastyle, 654.
euryzona, 652.
hexastyle, 653.
obtecta, 653.
octostyle, 653.
ovulina, 650.
quadrata, 650.
sexangulata, 653.
staurostyle, 651.
stenozona, 652.
subglobosa, 651.
tetraptera, 652.
tetrastyle, 652.
transversaria, 651.
Octotympanum, 999.

arborescens, 1000.
cervicorne, 1000.
octonarium, 1000.
octospinum, 1000.
Odontospha>ra, 102.
cyrtodon, 102.
monodon, 102.
OMMACAMPIDA, 392.
Ommatartus, 396.

amphicanna, 396.
amphisiphon, 396.
amphiobolus, 396.
Ommathymenium, 520.
OMMATIDA, 51.
Onimatocampe, 393.

ampbilonche, 395.
annulata, 393.
chsetopodum, 395.
erucaeformis, 394.
increscens, 393.
nereis, 394.
polyarthra, 393.
profundissima, 380.
setosa, 381. •
Ommatocyrtis, 366.
OMMATODISCIDA, 500.
Ommatodiscus, 500.
circularis, 501.
decipiens, 500.
fragilis, 502.
baeckelii, 501.
Isevigatus, 502.
stb'hrii, 501.
Ommalogramm.fi, 519.

nawcularis, 519.
Ommatospyris, 363.
apicala, 371.
cosdnoides, 363.
entomocora, 367.

Ommatospyris —

ethmaria, 363.
Icevis, 361.
penicillata, 370.
profunda, 365.
virginea, 363.
Orodendrum, 1598.
Orodietyum, 1601.
Orona, 1594.

crassissima, 1594.
maxima, 1594.
robusta, 1594.
ORONIDA, 1593.
Oronium, 1694.
Orophasparium, 818.
Orophaspidium, 818.
Orophaspis, 817.

astrolonche, 818.
diporaspis, 819.
furcata, 818.
gladiata, 818.
ramosa, 818.
tessaraspis, 819.
Oroplegma, 1600.

diplosphaera, 1600.
giganteum, 1601.
spinulosum, 1600.
spongiosura, 1601.
velatum, 1600.
Oroplegmium, 1600.
Oroscena, 1597.

bserii, 1598.
cuvieri, 1598.
danvinii, 1599.
duncanii, 1599.
gegenbauri, 1597.
huxleyi, 1599.
miilleri, 1598.
wolffii, 1598.
OROSOENIDA, 1593.
Oroscenium, 1597.
Orosphsera, 1594.

arborescens, 1597.
clavigera, 1596.
confluens, 1596.
foveolata, 1595.
furcata, 1596.
fusigera, 1595.
hastigera, 1595.
horrida, 1596.
ramigera, 1596.
spinigera, 1595.
scrpentina, 1595.
OROSPH.ERIDA, 1590.
Orothamnus, 1596.

arborescens, 1597.
Otosphsra, 116.

auriculata, 116.
polymorpha, 116.

PANACANTHA, 715.
Panarium, 388.

annularium, 389.
artophorum, 389.
facettarium, 388.
pipettarium, 389.
tubularium, 390.
Panartella, 377.
PANARTIDA, 375.
Panartissa, 379.
Panartoma, 381.
Panartura, 381.
Panartus, 376.

amphiconus, 379.
diploconus, 379.
fusiformis, 379.
pluteus, 382.
profundissimus, 380.
quadriceps, 380.
quadrigeminus, 381.
quadrijugus, 380.
setosus, 381.
spinosus, 381.
tetracolus, 377.
tetrameres, 378.
tetraphalangus, 378.
tetraplus, 377.
tetrathalamus, 378.
Panicium, 385.

amphacanthum, 385.
amphistylus, 385.
coronatum, 386.
scoparium, 385.
PANSOLENIA, 1521.
Pantopelta, 855.

icosaspis, 855.
PARADICTYIDA, 1099.
Paradictyum, 1102.

paradoxum, 1102.
Parastephanus, 1008.

asymmetricus, 1008.
circularis, 1008.
dispar, 1009.
quadrispinus, 100S.
PARASTEPHIDA, 987.
PAKATYMPANIDA, 1004.
Paratympauum, 1005.

decastylum, 1005.
hexastylum, 1005.
octostylum, 1005.
Patagospyris, 1087.

anthoeyrtis, 1088.
confluens, 1088.
lanccolata, 1088.
stiligera, 1088.
PELTOPHRAOTA, 803.
Pentactura, 479.

astropecten, 479.
pentactis, 479.
Peiitalacorys, 1371.

REPORT ON THE RADIOLARIA.

1789

Pentalastrum, 556.

asteracanthion, 556.

astropecten, 556.
cometa, 557.

ophidiaster, 557.
Pentaphormis, 1244.
Pentaplegma, 930.

decacantha, 930.
Pentasolenia, 113.
PENTASPYRIDA, 1052.
Pentaspyris, 1054.

isacantha, 1055.

pentacantha, 1054.
Penttnastmm, 557.

asteriscus, 557.

goniaster, 558.
Pentoniscus, 488.
Pentophiastrum, 558.

caudatum, 559.

dicranastrum, 558.

forcipatum, 559.
Periarachnium, 1297.

periplectum, 1297.
Perichlamydium, 499.

accreseens, 499.

cequale, 515.

asleriscus, 514.

limbo-turn, 514.

prsetextum, 499.

saturnus, 499.

spirals, 499.

spongiosum, 516.

venustum, 515.
Peridarium, 1153.
Peridium, 1153.

alatum, 1155.

cervinum, 1155.

curvipes, 1154.

lasanum, 1154.

palmipes, 1154.

papillatum, 1154.

spinipes, 1154.
Peripanarium, 390.

cenoconicum, 390.

cenocylindricura, 391.
Peripauartus, 382.

amphiconus, 383.

amphicorona, 387.

atraotus, 384.

cylindrus, 384.

Ijevigatus, 383.

palliatus, 382.
Peripanicium, 386.

amphicorona, 387.

ampbixiplms, 386.

coronarium, 387.
Periphsena, 426.

ciucta, 426.

decora, 426.

statoblastus, 426.

Periplecta, 926

cortina, 926.

monocyrtis, 927.

pteroscenium, 926.
PERIPYLARIA, 6.
PERIPYLEA, 6.
Peripyramis, 1162.

cirumtexta, 1162.

spongiosa, 1162.
Perispira, 494.

perforata, 495.

radiata, 495.
Perispongidium, 498.

irregulare, 498.
PERISPYRIDA, 1095.
Perispyris, 1098.

bicincta, 1099.

lentellipsis, 1099.

spongiosa, 1099.
Perizona, 427.

scutella, 427.

pterygota, 427.
Peromelissa, 1236.

calva, 1237.

capito, 1237.

phalacra, 1236.

psilocrana, 1237.
Petalospyrantha, 1060.
Petalospyrella, 1060.
Petalospyris, 1059.

anthemis, 1062.

anthocyrtoides, 1090.

arachnoides, 1065.

argiscus, 1062.

bellidiastrum, 1063.

carinata, 1074.

clathrus, 1049.

confluens, 1088.

corona, 1061.

diaboliscus, 1065.

dictyocubus, 1063.

dinoceras, 1063.

enpetala, 1061.

flalellum, 1174.

floscula, 1060.

foveolata, 1060.

furcata, 1064.

lobata, 1064.

novena, 1062.

ocellata, 1174.

octopus, 1061.

ophirensis, 1048.

papillata, 1063.

pentas, 1070.

platyacantha, 1060.

radicata, 1051.

seminulnm, 1046.

spinosa, 1048.

tessaromma, 1062.

triomma, 1060. t

Petalospyrissa, 1061.
Petalospyrorama, 1062.
PHACODISCARIA, 409.
PHACODISIDA, 419.
Phacodiscus, 424.

clypeus, 425.

echiniscus, 425.

grandis, 425.

lentiformis, 425.

rotula, 424.
Phacostaurium, 435.
Phacostaurus, 435.

magnificus, 436.

oceanidum, 435.

pyramidalis, 465.

quadrigatus, 436.
Phacostylium, 430.
Phacostylus, 430.

amphipyramis, 431.

ampbistylus, 430

amphixiphos, 430.

caudatus, 431.

maximus, 431.
PHJENOCALPIDA, 1157.
Phsenocalpis, 1173.

carinata, 1174.

flabellum, 1174.

ocellata, 1174.

petalospyris, 1173.
Phsenoscenium, 1174.

cladopodium, 1175.

hexapodium, 1175.

polypodium, 1175.
PhiEOColla, 1544.

primordialis, 1544.
PH^OCONCHIA, 1710.
PH^OCOSCINA, 1537.
PHJEOCYSTINA, 1542.
PH^ODARIA, 1521.
Phseodina, 1545.

cannopylea, 1546.

tripylea, 1545.
PHJEODINIDA, 1543.
PH^OGROMIA 1642.
PH^OSPH^RIA, 1590.
Pharyngella, 1662.

gastnea, 1662.

gastrula, 1662.

invaginata, 1662.

monoceros, 1662.
PHARYNOELLIDA, 1660.
Pliaryngosphsera, 98.

stomodiea, 98.
Phatnacantha, 765.

icosaspis, 765.

tessaraspis, 765.
Phatnasparium, 868.
PHATNASPIDA, 861.
Phatnaspidium, 871.
Phatnaspis, 870.

1790

THE VOYAGE OF H.M.S. CHALLENGER.

Phatnaspis —

coscinoides, 870.

cristate, 869.

ensiformis, 869.

fenestrata, 869.

haliommidium, 871.

lacunaria, 869.

loculata, 869.

mulleri, 871.

orthopora, 870.

polypora, 870.

quadratura, 871.

tabulata, 871.
Phatnasplenium, 870.
Phlebarachnium, 1295.

facetum, 1296.

selosum, 1296.

venosum, 1297.
Phcenicosphsera, 75.
Phormobotrys, 1124.

cannothalamia, 1125

hexathalamia, 1125.

pentathalamia, 1124.

polythalamia, 1125.

trithalamia, 1124.
Phormoeampe, 1456.

campanula, 1456.

conus, 1458.

eucalyptra, 1457.

lamprocyclas, 1457.

metalis, 1457.

mitra, 1458.
PHORMOCAMPIDA, 1453.
PHORMOCYKTIDA, 1365.
Phormocyrtis, 1368.

carinata, 1368.

costata, 1369.

embolum, 1369.

fastosa, 1369.

longicornis, 1370.

quadrate, 1369.
Phormosphsera, 61.
PHOEMOSPTRIDA, 1084.
Phormospyris, 1076.

tricostata, 1087.

tridentata, 1087.

trifoliata, 1087.
PHORTICIDA, 708.
Phorticium, 709.

abnorme, 710.

deforme, 710.

pylonium, 709.

spironium, 709.
Phortolarcus, 710.
Phortopj'le, 709.
Phractacantha, 755.

bifurca, 755.

bipennis, 755.
PHRACTACANTHIDA, 753.
Phractasparium, 808.

PHRACTASPIDA, 808.
Phractaspidium, 810.
Phractaspis, 809.

bipennis, 809.

cataphracta, 810.

complanata, 809.

condylophora, 809.

constricta, 810.

prototypus, 809.
Phractasplenium, 809.

bipenne, 809.
Phractopelta, 852.

aspidomma, 854.

dorataspis, 852.

diporaspis, 852.

dyadopora, 852.

haliomma, 854.

hexadopora, 853.

hystrtx, 854.

octedopora, 853.

tessaraspis, 853.

tessaromma, 854.

tetradopora, 853.
PHRACTOPELTIDA, 847.
Phrenocodon, 1433.

clathrostomium, 1434.

diaphragma, 1434.
Phyllostaurus, 744.
Physematium, 34.

atlanticum, 35.

mulleri, 35.

PlLOCYRTIDA, 1129.

Pipetta, 337.

conus, 338.

fusus, 337.

salpinx, 338.

tuba, 337.
Pipettaria, 339.

fusaria, 339.

tubaria, 339.
Pipettella, 304.

elongata, 305.

fusiformis, 304.

prismatica, 305.

tubulosa, 305.
Pityomma, 299.

drymodes, 260.

piniferum, 260.

scoparium, 259.
Plagiacantha, 909.

abietina, 910.

arachnoides, 910.

dodecantha, 910.

elatine, 911.

furcata, 910.

verticillata, 910.
PLAGIACANTHIDA, 898.
Plagiocarpa, 914.

procortina, 914.

procyrtella, 914.

PLAGONIDA, 906.
Plagonidium, 913.

bigeminum, 913.

quadrigeminum, 914.
Plagoniscus, 912.

cortinaris, 913.

euscenium, 912.

nassellaris, 913.

tripodiscus, 912.
Plagoniuin, 916.

arborescens, 917.

distriactis, 917.

lampoxanthium, 907.

sphajrozoum, 916.

trigeminum, 9] 7.
Platybursa, 1051.

compressa, 1051.
Platycryphalus, 1298.

sethodisciis, 1298.
PLECTANIDA, 919.
Plectaniscus, 924.

archiscenium, 925.

cladoscenium, 925.

clathrocorys, 925.

cortiniseus, 925.

tripodiscus, 925.
Plectanium, 928.

ovodimare, 928.

sphaerozoum, 928.

trigemiuum, 928.
PLECTELLABIA, 895.
PLECTIDA, 898.
Plectocoronis, 979.

auacantha, 979.

pentacantha, 979.

triacantha, 979.
PLECTOIDEA, 898.
Plectophora, 922.

arachnoides, 922.

novena, 923.

pyramidalis, 923.

triomma, 922.
Plectopyrarais, 1256.

dodecomma, 1258.

fenestrata, 1259.

furcata, 1259.

heteromma, 1259.

hexapleura, 1257.

lagena, 1260.

magnifica, 1257.

polygonomma, 1258.

polypleura, 1260.

quadratomma, 1258.

serrate, 1259.

spongiosa, 1261.

trapezomma, 1258.
Plegmosphsera, 87.

ccelopila, 88.

entodictyon, 83.

exodictyon, 89.

REPORT ON THE RADIOLARIA.

1791

Plegmosphsera —

leptodictyon, 89.

leptoplegma, 89.

maxima, 88.

pachypila, 88.

pachyplegma, 89.

polybrocha, 930.
PLEGMOSPH.ERIDA, 86.
Pleurasparium, 811.
Pleuraspidium, 812.
Pleuraspis, 811.

amphithecta, 811.

costata, 812.

horrida, 811.

pyrarnidalis, 812.

ram o.sa, 812.
Pleuropodium, 1336.

charybdeum, 1336.

cortina, 1336.
Podocanipe, 1445.

conica, 1446.

cornuta, 1446.

trietenota, 1446.

tripodiscus, 1446.

PODOCAMPIDA, 1435.

Podoeoronis, 980.

cortiniscus, 981.

dipodiscus, 980.

hexapodiscus, 982.

petalospyris, 982.

polypodiscus, 982.

tetrapodiseus, 981.

toxarium, 980.

tripodiscus, 981.
Podocyrtarium, 1337.
Podocyrtecium, 1339.

PODOCYRTIDA, 1314.

Podooyrtidium, 1344.
Podocyrtis, 1337.

acukata, 1373.

cegles, 1391.

aerostatica, 1252.

amphiacantha, 1344.

ampla, 1348.

argulus, 1344.

argus, 1346.

attenuata, 1338.

bicornis, 1349.

brevipes, 1340.

bromia, 1349.

campanclla, 1331.

centriscus, 1341.

charybden, 1336.

collaris, 1340.

conica, 1338.

conulus, 1339.

corytha'ola, 1339.

costata, 1345.

cotJmrnata, 1353.

cristata, 1342.

Podocyrtis —

dipus, 1349.

divergens, 1340.

domino,, 1387.

ehrenbergii, 1344.

euceros, 1342.

eulophos, 1346.

favosa, 1346.

floribunda, 1347.

flosculata, 1341.

fusiformis, 1346.

hexagonalis, 1343.

lithoconus, 1348.

lysea, 1348.

magnifica, 1341.

micracantha, 1761.

mitra, 1345.

mitrella, 1345.

nana, 1348.

ovata, 1343.

papalis, 1344.

parvipes, 1371.

pedicellaria, 1347.

pentacantha, 1371.

princeps, 1342.

prismatica, 1340.

puetta, 1387.

radicata, 1351.

rhizodon, 1351.

scaphopodia, 1347.

schomburgkii, 1343.

sinuosa, 1347.

sphrerogaster, 1349.

spinosa, 1169.

surena, 1339.

tetracantha, 1371.

thyrsoceras, 1338.

triacantha, 1350.

tridactyla, 1339.

tripodiscus, 1338.

tripus, 1349.

urceolata, 1343.

ventricosa, 1347.
Podocyrtonium, 1347.
Polyalacorys, 1374.

POLYCYRTIDA, 1103.
POLYCYSTINA, 1.

Polyplagia, 917.

duodenaria, 918.

novenaria, 918.

octonaria, 918.

septenaria, 918.

viminaria, 919.
POLYPLAGIDA, 917.

Polyplecta, 929.

decacantha, 930.
dumetum, 930.
enneacantha, 929.
heptacantha, 928.
polybrocha, 930.

POLYPLECTIDA, 929.

Polypleuris, 1260.
Polypetta, 1676.

alveolata, 1676.

mammillata, 1677.

polynema, 1676.

tabulata, 1677.

POLYPRUNIDA, 288.

Polysolenia, 113.
setosa, 100.

POLYSPHJERIDA, 52.
POLYSPYRIDA, 1059

Polystichia, 1762.

ehrenbergii, 1762.

haeckelii, 1762.

muelleri, 1762.
Porcupinia, 1663.

aculeata, 1663.

cordifonnis, 1663.
Porocapsa, 800.

coronodon, 801.

murrayana, 800.

octodon, 800.

tetrodon, 800.
POROCAPSIDA, 799.
PORODISCIDA, 481.
Porodiscus, 491.

bispiralis, 497.

bilix, 496.

centrospira, 495.

concentricus, 492.

deformis, 498.

duplex, 497.

ellipticus, 494.

flustrella, 493.

helicoides, 496.

heterocyclus, 494.

irregularis, 498.

macroporus, 493.

microporus, 493.

operculina, 496.

orbiculatus, 492.

perispira, 495.

quadrigatus, 494.

radiatus, 495.

semispiralis, 497.

sorites, 493.

spiralis, 496.
Porospathis, 1677.

mammillata, 1677.

tubulata, 1677.
Porosphsera, 67.
Prismatium, 1009.

tripleurum, 1010.

tripodinm, 1009.
Pristacantha, 765.

dodecodon, 766.

octodon, 765.

polyodon, 766.
Pristodiscus, 418.

1792

THE VOYAGE OF H.M.S. CHALLENGER.

Procyttarium, 13.

primordiale, 13.
PKOTYMPANIDA, 991.
Protympanium, 991.

amphipodium, 992.

primordiale, 991.

trissocircus, 992.
Prunocarpus, 316.

artocarpium, 316.

datura, 316.

melocactus, 317.

sparganium, 316.
PRUNOIDEA, 284.
PRUNOPHRACTA, 859.
Prunosphrera, 74.
Prunulum, 313.

amygdalum, 313.

cerasum, 313.

coccymelium, 313.

crenatum, 314.

fenestratum, 315.

frngulum, 313.

persicum, 314.

pyrenium, 315.

triplex, 314.
Pseudocubns, 1010.

hexapylus, 1011.

obeliscus, 1010.

octostylus, 1010.
Psilomelissa, 1208.

calvata, 1209.

galeata, 1208.

hertwigii, 1209.

phalaera, 1208.

sphserocephala, 1209.
Pteractis, 535.

elegans, 535.
Pterocanarium, 1329.
Pterocanidium, 1332.
Pterocanium, 1328.

barbadense, 1318.

bibrachiatum, 1327.

bicorne, 1332.

bombus, 1443.

eampanella, 1331.

charybdeum, 1336.

contiguum, 1330.

davisianum, 1437.

depressum, 1331.

eucolpum, 1332.

faki/erum, 1317.

gravidum, 1329.

orcinum, 1329.

prsetextuni, 1330.

proserpinse, 1329.

pyramis, 1330.

saba, 1317.

sphinx, 1443.

trieolpum, 1331.

trilobum, 1333.

Pterocanium—

virgineum, 1330.
Pterocodon, 1333.

apis, 1318.

campana, 1333.

eampanella, 1223.

davisianus, 1437.

favosus, 1334.

ornatus, 1333.
Pterocorys, 1316.

apis, 1318.

aquila, 1317.

barbadensis, 1318.

campanula, 1316.

carinata, 1316.

columba, 1317.

falcifera, 1317.

hirundo, 1318.

macroptera, 1321.

melitta, 1319.

pipetta, 1320.

prismatica, 1320.

rhinoceros, 1320.

sabse, 1317.

tricornis, 1320.

tubulosa, 1319.

turgida, 1319.

zittelii, 1321.
Pterocorythium, 1320.
Pterocyrtidium, 1316.

barbadense, 1318.

ziUelii, 1321.
Pteropilium, 1326.

bombus, 1443.

clathrocanium, 1327.

eques, 1327.

hoplites, 1327.

pyramis, 1443.

sphinx, 1443.

stratiotes, 1326.
Pteroscenium, 1151.

arcadophorum, 1152.

areuatum, 1152.

macropodium, 1153.

pinnatum, 1152.

spinulosum, 1152.

tripocolpum, 1153.
Pterosyringium, 1319.

tubuhsum, 1319.
PYLOBOTRYIDA, 1119.
Pylobotrys, 1121.

cerebralis, 1122.

fontinalis, 1122.

putealis, 1121.
PTLODISCIDA, 561.
Pylodiscus, 570.

cardiopylus, 571.

nephropylus, 571.

sexangularis, 570.

triangularis, 570.

Pylolena, 568.

inennis, 568.

armata, 568.
PTLONIDA, 628.
Pylonium, 654.

circozonium, 654.

hexazonium, 655.

nephropylium, 955.

octacanthum, 655.

quadricorne, 655.

stenozonium, 656.
Pylospira, 697.

tetrapyle, 698.

octopyle, 698.

cymbium, 698.
Pylospirema, 697.
PTLOSPTRIDA, 1078.
Pylospyris, 1083.

canarieusis, 1084.

denticulata, 1083

trinacria, 1083.
Pylospironium, 698.
Pylozonium, 659.

novemcinctum, 659.

octacanthum, 660.

Quadriloncharium, 776.

QUADRILONCHIDA, 766.

Quadrilonchidium, 777.
Quadrilonche, 776.

mesostaura, 777.

platystaura, 777.

telostaura, 777.

tetrastaura, 776.

Rhaphidocapsa, 211.
Rhaphidococcus, 210.

acufer, 211.

lurianensis, 1762.

simplex, 216.
Rhaphidodrymus, 214.
Rhaphidosphsera, 214.

reticulata, 217.
Rhaphidozoum, 46.

acuferum, 46.

arachnoides, 47.
• ascensionis, 48.

asperum, 47.

australe, 48.

capense, 48.

neapolitanum, 47.

pacificum, 46.

pandora, 49.

patagonicum, 48.

pelagicum, 46.

polymorphum, 49.
Itliizoplegma, 275.

lychnosphaera, 275.

polyacanthum, 275.

radicatum, 276.

REPORT ON THE RADIOLARIA.

1793

Rhizoplegma —

spirale, 275.

trigonacanthum, 276.
Rhizosphsra, 283.

leptomita, 284.

serrata, 284.

trigonacantha, 283.
Rhodosphsera, 83.

hexagonia, 83.

melitomma, 83.

palliata, 83.

pentaphylla, 83.
RHODOSPYRIDA, 1087.
Rhodospyris, 1088.

triceros, 1089.

tricornis, 1089.
Rhopalastrella, 526.
Rhopalastromma, 528.
Rhopalastrum, 526.

arcticum, 529.

bandaicum, 525.

clavatum, 528.

hexaceros, 529.

hcxagonum, 525.

irregulare, 528.

lagenosum, 527.

malleus, 527.

martellum, 528.

pistillum, 527.

triceros, 529.

trispinomm, 525.

truncatum, 526.

ypsilinum, 528.
Rhopalatractus, 1-360.

fenestratus, 1361.

foveolatus, 1361.

fusiformis, 1361.

pentacanthus, 1361.
Rhopalocanium, 1359.

cortinium, 1359.

delphicum, 1360.

ksanura, 1359

ornatum, 1359.

prismaticum, 1357.

pythia, 1360.
Rhopalodictyum, 589.

abyssorum, 589.

bifidum, 590.

curvatum, 591.

elongatum, 591.

subacutum, 590.

truncatnm, 589.

zittelii, 590.

Sagena, 1605.

crucifera, 1606.

pertusa, 1606.

ternaria, 1606.

triangula, 1606.
SAGBNIDA, 1605.

(ZOOL. CHALL. EXP. — PART XL.-

Sagenoscena, 1610.

coronata, 1611.

cruciata, 1611.

ornata, 1610.

penicillata, 1611.

spathillata, 1611.

stellata, 1610.
SAGMARIDA, 1612.
Sagmarium, 1612.

plegmosphserium, 1612.

spongodictyum, 1612.

trigonizon, 1612.
Sagmidium, 1613.

crucicorne, 1613.

multicorne, 1614.

quadricorne, 1614.

tricorne, 1613.

unicorne, 1613.
Sagoplegma, 1614.

pyramidophora, 1614.

scenophora, 1615.
Sagoscena, 1608.

castra, 1608.

cruciarium, 1609.

debilis, 1609.

fragilis, 1610.

gracilis, 1609.

pellorium, 1609.

prsetorium, 1609.

tentorium, 1608.
Sagosphoera, 1607.

coronilla, 1608.

furcilla, 1607.

penicilla, 1607.

trigonilla, 1607.

verticilla, 1607.
SAGOSPH.SRIDA, 1601.
Saturnalis, 131.

annularis, 132.

circoideus, 132.

circularis, 131.

cyclus, 132.

rotula, 133.

trochoides, 132.
Saturnalium, 132.
Saturninus, 146.

triplex, 146.
Saturnulus, 141.

annulus, 141.

circulus, 141.

ellipticus, 141.

planetes, 142.
Schizomma, 645.

quadrilobum, 645.
SEMANTIDA, 953.
Semantidiura, 960.

haeckelii, 961.

hexastoma, 960.

sexangulum, 960.

signatorium, 961.
1887.)

Semantis, 956.

biforis, 956.

dipyla, 957.

distephanus, 957.

distoma, 957.

sigillum, 957.

spinescens, 958.
SEMANTISCIDA, 956.
Semantiscus, 966.

hexapodius, 966.

hexapylus, 967.

hexaspyris, 966.
Semantrum, 958.

biitschlii, 959.

mulleri, 959.

quadrifore, 958.

signarium, 960.

sphragisma, 959.

tetrapylum, 959.

tetrastoma, 959.
Sepalospyris, 1081.

platyphylla, 1081.

polyphylla, 1081.
Sethamphora, 1249.

aerostatica, 1252.

ampulla, 1251.

costata, 1251.

dodecapleura, 1250.

enneapleura, 1250.

favosa, 1252.

hexapleura, 1250

microstoma, 1252.

mongolfieri, 1251.

serrata, 1251.
Sethocapsa, 1310.

ampulla, 1311.

bulla, 1311.

lagena, 1310.

macroceros, 1310.

nidua, 1311.

pyriformis, 1310.

staurocephala, 1311.
SETHOCAPSIDA, 1309.
Sethocephalus, 1298.

eucecryphalus, 1298.

platycryphalus, 1298.
Sethochytris, 1239.

barbadensis, 1239.

pyramis, 1240.

triangula,' 1240.

triconiscus, 1239.
Sethoconus, 1290.

ampliatus, 1291.

anthocyrtis, 1296.

bimarginatus, 1295.

cervus, 1292.

clathratus, 1295.

cucullaris, 1290.

facetus, 1296.

gracilis, 1295.

Kr 225

1794

THE VOYAGE OF H.M.S. CHALLENGER.

Sethoconns —

hexagonalis, 1293.

larvatus, 1282.

longisetus, 1294.

lophophtena, 1292.

initra, 1291.

nassa, 1293.

orthoceras, 1294.

pileus, 1291.

profundus, 1294.

rayianus, 1291.

setosus, 1296.

tabulatus, 1293.

trichostylus, 1294.

trochus, 1290.

venosus, 1297.

verrucosus, 1293.

virgultus, 1296.
SETHOCOKIDA, 1289.
Sethocorys, 1301.

achillis, 1301.

ajacis, 1302.

amphora, 1302.

armadillo, 1302.

odysseus, 1302.

patrocli, 1301.
SETHOCYRTIDA, 1288.
Sethocyrtis, 1298.

agamemnonis, 1300-.

cancrina, 1292.

cassis, 1301.

diomedis, 1292.

menelai, 1299.

oxycephalis, 1299.

pleuracantha, 1300.

subacuta, 1300.
SETHODISCIDA, 422.
Sethodiscus, 422.

cristatus, 424.

echinatus, 424.

lenticula, 423.

macrococcus, 423.

macroporus, 422.

micrococcus, 423.

microporus, 422.

phacoides, 422.

radians, 423.
Sethomelissa, 1207.

hymenoptera, 1238.
Sethoptera, 1232.

lagena, 1233.

Oceania, 1232.

pyrum, 1232.

tricostata, 1232.
SETHOPERIDA, 1232.
Sethophsena, 1285.

enneaptera, 1286.

hexaptera, 1286.

polyptera, 1286.

tetraptera, 1285.

SETHOPHjENIDA, 1285.

SETHOPHORMIDA, 1143.
Sethophormis, 1243.

arachnium, 1247.

asteriscus, 1244.

astrodiscus, 1244.

anrelia, 1248.

cruciata, 1243.

dodeeaster, 1248.

enneactis, 1247.

enneastrum, 1246.

eupilium, 1247.

floscula, 1249.

hexagonalis, 1245.

hexalactis, 1245.

leptopilium, 1249.

leptoscenium, 1249.

medusa, 1244.

octalactis, 1245.

pentalactis, 1244.

rotula, 1246.

triloba, 1246.

umbrella, 1248.
SETHOPILIDA, 1195.
Sethopilium, 1202.

cyrtopus, 1202.

macropus, 1203.

orthopus, 1202.
Sethopyramis, 1253. •

bicornis, 1256.

cyclomma, 1255.

dodecalactis, 1256.

enneactis, 1254.

eupilium, 1247.

hexagonalis, 1255.

hexalactis, 1253.

maxima, 1256.

quadrata, 1254.

quadratella, 1254.

scalaris, 1253.

spinosa, 1255.

trapezoides, 1254.
Sethornithium, 1356.

dictyopterum, 1356.
Sethosphaera, 71.

entosiphonia, 71.

entosolenia, 71.

rhodococcus, 237.
Sethostaurium, 438.
Sethostaurus, 433.

conostaurus, 433.

coronatus, 434.

cruciatus, 434.

gigas, 435.

orthostaurus, 433.

recurvatus, 434.

rhombostaurus, 434.
Sethostylium, 428.
Sethostylus, 429.

dentatus, 429.

Sethostylus —

dicylindrus, 428.

distyliscus, 428.

endostylus, 413.

hastatus, 429.

serratus, 429.

spicatus, 430.
Siphocampe, 1490.

annulosa, 1500.

caminosa, 1500.

erucosa, 1500.

quadrantalis, 1501.

spiralis, 1501.

tubulosa, 1500.
Siphocampium, 1501.
Siphocampula, 1499-.
SipTwnaspis, 823.

cristaia, 823.
Siphonosphsera, 104.

chonophora, 107.

conifera, 106.

cyathina, 105.

fragilis, 106.

infundibulum, 105.

macrosiphonia, 107.

marginata, 104.

pansiphonia, 104.

patinaria, 105.

pipetta, 108.

polysiphonia, 106.

serpula, 107.

socialis, 106.

tubulosa, 105.
Solenosphosra, 112.

amalthea, 115.

ascensionis, 115.

cornucopias, 115.

megalactis, 114.

pandora, 113.

serpentina, 114.

variabilis, 113.

venosa, 114.
Soreuma, 713.

acervulina, 714.

acinosum, 713.

irregulare, 713.

setosum, 714.

spinosum, 714.

subglobosurn, 713.

SdREUMIDA, 712.

Sorolarcus, 715.

larnacillifer, 715.

tetrapylifer, 715.

terminalis, 715.
SPHJERELLARIA, 49.
SPH.ERIDEA, 50.
Sphserocapsa, 798.

cruciata, 798.

dentata, 798.

quadrata, 798.

REPORT ON THE RADIOLARIA.

1795

pavimentata, 798.
SPH.EROCAPSIDA, 795.
SPH^ROIDEA, 50.
SPH.SROPHRACTA, 795,
Sphaerospyris, 1099.

globosa, 1100.

quadriforis, 1100.

sphaera, 1100.
SPH.EROSTYLIDA, 133.
Sphaerostylus, 138.

clio, 139.

cottus, 140.

diadema, 139.

flexuosus, 138.

hippocampus, 139.

liostylus, 138.

ophidium, 140.

trigla, 140.
SPHJEHOZOIDA, 38.
Sphserozoum, 40.

acuftrum, 46.

alveolatum, 43.

araucaria, 44.

arborescens, 44.

annatum, 43.

atlanticum, 40.

biccllulare, 25.

bifurcum, 33.

circumtextum, 45.

furcatum, 42.

furculosum, 42.

fiiscum, 43.

geminatum, 45.

hamatum, 41.

hexactinium, 41.

inerme, 25.

italicum, 40.

medusinum, 41.

neapolitanum, 47.

octoceras, 44.

orientate, 1763.

ovodimare, 42.

pelcuficum, 28.

punctatum, 43.

punctatum, 42.

quadrigeminum, 44.

sanderi, 1763.

spinulosum, 40.

stellatum, 45.

triactinium, 41.

trigeminum, 43.

variabile, 45.

verticillatum, 44.
Spiremarium, 692.
Spirema, 692.

diplospira, 693.

flustrella, 692.

lentellipsis, 692.
melonia, 692.

Spirema —

subglobosum, 693.
SPIREMIDA, 691.
Spiremidium, 693.
Spirocampe, 1511.

allospira, 1511.

callispira, 1511.

polyspira, 1511.
Spirocyrtidium, 1509.
Spirocyrtis, 1508.

cornutella, 1509.

diplospira, 1510.

heniispira, 1510.

holospira, 1509.

merospira, 1510.

scalaris, 1509,
Spirocyrtoma, 1609.
Spironetta, 701.
Spironilla, 702.
Spironium, 701.

arbustum, 702.

diagonale, 702.

octonium, 701.

spinosum, 702.
Spongaster, 596.

cruciatus, 597.

orthogonus, 598.

pentacyclus, 598.

quadratus, 597,

scyllseus, 598.

tetras, 597.
Spongasteriscus, 594.

armatus, 595.

clavatus, 595.

furcatus, 595.

mucronatus, 595.

myelastrum, 596.

ovatus, 594.

quadricornis, 596.

tetraceros, 596.
Spongatractus, 350.

fusiformis, 351.

pachystylus, 350.

streptacanthus, 351.
Spongechinus, 272.

cavus, 273.

multiaculcatus, 271.

serrulatus, 273.

setosus, 273.
SPONGELLIPSIDA, 341.
Spongellipsis, 34.

aplysina, 342.

aspera, 342.

lams, 342.

setosa, 342.

spinosa, 342.
Spongiomma, 270.

asteroides, 272.
clavatum, 271.
denticulatum, 270.

Spongiomma —

helioides, 271.

multiaculeum, 271.

radiatum, 270.

spathillatum, 270.
SPONGIOMMIDA, 270.
SPONGOBRAOHIDA, 587.
Spongobrachinm, 587.

ellipticum, 588.

lanceolatum, 588.
Spongocore, 346.

chrysalis, 346.

cincta, 346.

diplocylindrus, 346.

puella, 347.

pupula, 347.

velata, 347.
Spangocydia, 577.

cfiarybdcea, 593.

cycloides, 578.

elliptica, 588.

orthogana, 598.

scyllcea, 598.

triangularis, 578.
SPONGOCTCLIDA, 573.
Spongocyrtis, 1188.

arachnoides, 1189.

mentis ovis, 1189.
Spongodictyon, 90.

arcadophoron, 9L

cavernosum, 91.

spongiosum, 90.

trigonizon, 91.
SPONGODISCIDA, 573.
Spongodisculus, 576.
Spongodiscus, 576.

aculcatus, 583.

biconcavus, 577.

charybdtetis, 593.

cycloides, 578.

ellipticiLs, 588.

favus, 577.

florealis, 578.

inediterraneus, 576.

orthogonus, 598.

quadricornis, 596.

radiatus, 576.

resurgens, 577.

scyllceus, 598.

spiralis, 578.

spoiigocyclia, 378.
Spongodruppa, 349.

elliptica, 350.

frangula, 349.

lentisca, 349.

pistacia, 349.

polyacantha, 350.

terebiiitha, 349.
SPONGODRUPPIDA, 348.
Spongodrymus, 272.

1796

THE VOYAGE OF H.M.S. CHALLENGER.

Spongodrymus —

abietinus, 272.

elaphococcus, 272.
SPONGOLARCIDA, 613.
Spongolarcua, 613.

amphicentria, 614.

dimensivus, 613.

lentellipsis, 613.

triaxonius, 613.
Spongolena, 587.

cypsclura, 588.

rhopalura, 587.

spongura, 587.
Spongoliva, 352.

amygdalina, 352.

cerasina, 352.

daturina, 353.

opuntina, 352.

persicina, 352.

prunulina, 352.
Spongolonche, 579.

amphistyla, 580.

conostyla, 580.
Spongolouchis, 149.

compacta, 149.

laxa, 149.
Spongomelissa, 1209.

spongiosa, 1210.
SPONGOPHACIDA, 575.
Spongophacus, 579.

periphsena, 579.
Spongophortis, 711.

larnacilla, 711.

radiosa, 711.

spongiosa, 711.
Spongopila, 274.

dichotoma, 274.

verticillata, 275.
Spongoplegma, 89.

antarcticnm, 90.
Spongoprunum, 347.

amphicylindrus, 348.

amphilonche, 347.

atractus, 348.
Spongopyramis, 1260.

spongiosa, 1261.

spongoplecta, 1261.
Spoiigosphsera, 282.

helioides, 283.

pachystyla, 350.

polyacantha, 282.

quadricuspis, 283.

rhabdostyla, 584.

streptacantha, 282.
SPONGOSPH.SRIDA, 52.
Spongospira, 578.

florealis, 578.

spiralis, 578.
Spongostaurus, 582.

cruciatus, 582.

Spongostaurus —

hastatus, 582.
quadratus, 582.
serratus, 582.
SPONGOSTYLIDA, 148.
Spongostylidium, 150.

streptacanthum, 150.
Spongostylus, 749.

gladiatus, 150.
hastatus, 149.

prunococcus, 354.
serratus, 150.
Spongothamnus, 274.
furcatus, 274.

scoparius, 274.
Spongotripus, 580.

irregularis, 581.

neumayri, 581.

regularis, 580.

strepsiceros, 581.

ypsilon, 581.
SPONGOTROCHIDA, 579.
Spongotrochiscus, 585.
Spongotrochus, 585.

araehnius, 583.

brevispinus, 586.

craticulatus, 583.

ehrenbergii, 1763.

heteracanthus, 584.

longispinus, 586.

multispinus, 586.

parma, 587.

scutella, 586.
SPONGURIDA, 339.
Spongunis, 343.

asper, 344.

cylindricus, 344.

phalanga, 343.

radians, 345.

salpa, 614.

spongeehinus, 345.

stuparius, 343.

stypticus, 343.

tricolus, 344.
Spongoxiphus, 353.

prunococcus, 354.

sphferococcus, 353.
SPUMBLLARTA, 6.
Spyrida, 1015.
SPTRIDINA, 1015.
Spyridobotrys, 1083.

trinacria, 1083.
SPYROIDEA, 1015.
Stauracantha, 761.

bifurca, 764.

diplostaura, 762.

johannis, 763.

murrayana, 763.

orthostaura, 762.

pinnulata, 763.

Stauracantha —

quadrifurca, 764.

scalaris, 763.

stauraspis, 764.

tetrastaura, 762.
STAURACANTHIDA, 758.
Stauracanthidium, 764.
Stauracanthonium, 762.
STAURAOONTIDA, 163.
Stauracontium,

antarcticum, 165.

cruciferum, 164.

daturseforme, 164.

papillosum, 165.

setosum, 165.

sparganiuin, 165.

tetracanthum, 164.

tetracontium, 164.
Stauractinium, 478.
Stauractura, 477.

medusina, 478.

quadrata, 478.

tetragona, 478.
Stauracturium, 477.
Stauralastrum, 540.

antiquum, 541.

clavigerum, 541.

cruciforme, 540.

dilatatum, 541.

horridum, 542.

lanceolatum, 540.

ordo, 540.

rhopalophorum, 541.

staurolonche, 542.
Staurancistra, 162.

quadricuspis, 162.
Staurasparium, 831.
STATIRASPIDA, 830.
Stauraspidium, 831.
Stauraspis, 831.

cruciata, 831.

furcata, 832.

Stauracantha, 832.

xiphacantha, 831.
Staurectodiscus, 416.
Staurentodiscus, 416.
STAUEOCARTIDA, 167.
Staurocaryum, 167.

arborescens, 167.
STAUROCROMYIDA, 166.
Staurocromyum, 166.

quadrispinum, 166.

quadruplex, 166.
Staurocylia, 465.

cruciata, 465.

magniducis, 466.

phacostaurus, 465.

serrata, 465.
Staurodictya, 506.

ciliata, 506.

REPORT ON THE RADIOLARIA.

1797

Stanrodictya —

cruciate, 507.

elegans, 507. ,

grandis, 508.

medusa, 506.

ocellata, 508,

quadrispina, 507.

splendens, 508.
Staurodoras, 163.

liassica, 168.

mojsisovicsi, 168.

spongosphajra, 168.

wandae, 169.
STAURODORIDA, 168.
Stanrolithium, 771.

crueiatum, 771.
Steurolonche, 159.

aperta, 159.

brunonis, 159.

epicurii, 161.

feuerbachii, 160.

gassendii, 161.

hexagona, 158.

holbachii, 160.

lucretii, 161.

moleschottii, 160.

pertusa, 159.

spinozae, 159.

straussii, 160.
STAUROLONCHIDA, 158.
Steurolonchidium, 162.

artioscelides, 162.

perspicuum, 162.
Stauropelta, 859.

cruciata, 859.

stauropora, 859.
Staurosphsera, 153.

andreae, 154.

apostolorum, 155.

bartholomaei, 156.

Christiana, 153.

crassa, 155.

cruciata, 153.

jacobi, 154.

johannis, 153.

judoe, 155.

matthaei, 156.

pauli, 153.

petri, 153.

phillippi, 154.

simonis, 154.

thaddsei, 156.

thomse, 155.
STAUROSPH^RmA, 151.

Staurospira, 507.
STAUROSTYLIPA, 152.
Steurostylus, 156.

germanicus, 157.

graecus, 156.

latinus, 157.

STAITEOTHOLIDA, 670.
Staurotholonium, 675.

alternatum, 675.

bicrueiatum, 676.

biquadratum, 675.

lenticulare, 676.

octodoratium, 676.

octodoronium, 676.
Staurotholus, 673.

cruciatus, 673.

decastylus, 674.

dodecastylus, 674.

octostylus, 674.

polystylus, 674.

quadratus, 673.

tetrastylus, 673.
Stauroxiphos, 163.

gladius, 163.
Stegaspis, 819.
Stephanastrum, 549.

capitatum, 549.

quadratum, 549.

rhombus, 549.
STEPHANIDA, 937.
Stephaniscus, 965.

medusinus, 965.

(juadrifurcus, 965.

q.uadrigatus, 965.

tetrapodius, 965.
Stephanium, 952.

quadrupes, 952.

tetrapus, 952.
Stephanolithis, 953.

miilleri, 959.

spinescens, 958.
Stephanophsena, 1178.
Stephanospyris, 1042.

cordata, 1042.

excellens, 1043.

verticillata, 1043.
STEPHIDA, 931.
STEPHOIDEA, 931.
Stichocampe, 1443.

convergens, 1444.

divergens, 1444.
Stichocapsa, 1515.

compacta, 1517.

compressa, 1516.

cylindrica, 1518.

hexacola, 1517.

monstrosa, 1517.

paniscus, 1518.

pentacola, 1517.

pyriformis, 1516.

quadrigata, 1515.

radicula, 1518.

subglobosa, 1516.

subligata, 1518.

tetracola, 1515.

tricincta, 1516.

STICHOCAPSIDA, 1511.
STICHOCORIDA, 1468.
Stichocorys, 1479.

bserii, 1479.

huschkei, 1480.

miilleri, 1480.

okenii, 1480.

panderi, 1479.

rathkei, 1480.

wolffii, 147».
STICHOCYRTIDA, 1434.
Stichocyrtis, 1489.
Sticholagena, 1449.
Stichopera, 1447.

cUrata, 1449.

lagena, 1448.

«vata, 1448.

pectinata, 1449.

serrata, 1448.

verticillata, 1449.
STICHOPEEIDA, 1147.
Stichoperina, 1448.
Stichophsena, 1465.

darwiniana, 1465.

gcetheani, 1466.

nonaria, 1466.

novena, 1466.

ritteriana, 1465.
STICHOPH^NIDA, 1463.
Stichophaenidium, 1465.
Stichophsenoma, 1466.
STICHOPHORMIDA, 1454.
Stichophormis, 1454.

cornutella, 1455.

lucerna, 1455.

novena, 1455.

pyramidalis, 1454.

radial, i, 1456.
Stichophorraiscus, 1455.
Stichophormium, 1454.
STICHOPILIDA, 1436.
Stichopilidium, 1438.
Stichopiliam, 1436.

bicorne, 1437.

campanulatum, 1438.

oortina, 1437.

costatum, 1437.

davisianum, 1437.

macropterum, 1438.

pectinatum, 1439.

thoracopterum, 1439.

triserratum, 1438.
Stichopodium, 1447.

dietyopodium, 1447.
Stichopterium, 1444.

dietyopodium, 1445.

pterocanium, 1445.

virgineum, 1445.
Stichopterygium, 1442.

tanypterum, 1442.

1798

THE VOYAGE OF H.M.S. CHALLENGER.

Stichopterygium —

anomalum, 1442.
Stigmosphsera, 68.

actinocentra, 68.
Stomatodiscus, 502.

amphistomus, 502.

osculatus, 503.
Streblacantha, 706.

calcarina, 706.

hastigerina, 707.

siderolina, 706.
STREBLACANTHIDA, 704.
Streblonia, 704.

bulimina, 705.

globigerina, 704.

planorbulina, 705.

polymorphina, 705.

pulvinulina, 706.

rosalina, 705.

nderolma, 706.

nvigerina, 704.
STKEBLONIDA, 702.
Streblopyle, 707.

helicina, 707.

spirulina, 707.
STKEBLOFYLIDA, 704.
Stylactis, 532.

triangulum, 533.

rittelii, 534.
Stylartus, 357.

bipolaris, 357.

bicuspis, 357.

palatus, 358.

penicillus, 358.
Stylatractus, 328.

cardnus, 330.

compactus, 329.

disetanius, 331.

fusiformis, 329.

giganteus, 329.

neptnnus, 328.

papillosus, 331.

sethoporus, 330.

variabilis, 330.
Stylectodiscus, 413.
Stylentodiscus, 413.
Stylochlamydium, 514.

sequale, 515.

asteriscus, 514.

Kmbatum, 514.

perispirale, 515.

spongiosum, 516.

venustum, 515.
Stylocoronis, 982.
Stylocromyum, 147.

amphiconus, 147.

amphipyramia, 147.

tetraphractum, 335.
Stylocyclia, 462.

amphacantha, 463.

Stylocyclia —

arachnia, 510.

dimidiata, 462.

excavate, 463.

prionacantha, 462.
STYLOCYCLIDA, 461.
Stylodictya, 509.

arachnia, 510.

bispiralis, 497.

centrospira, 512.

clavata, 513.

dujardinii, 513.

cchinastruni, 513.

forbesii, 510.

gracilis, 509.

haeckelii, 510.

hastata, 510.

heliospira, 512.

hertwigii, 513.

multispina, 510.

occllata, 508.

octogonia, 511.

perispira, 511.

guadrispina, 507.

setigera, 512.

solmaris, 511.

splendens, 508.

stellata, 510.
STYLODICTYIDA, 50!>.
Stylodiscus, 413.

amphistylus, 413.

endostylus, 413.
Stylosphsera, 133.

calliope, 134.

carduus, 330.

clio, 134.

eoronata, 326.

dixyphos, 135.

erato, 137.

euterpe, 135.

flexuosa, 138.

hippocampus, 324.

hispida, 136.

holosp/uera, 150.

jugata, 137.

Icevis, 327.

liostylus, 136.

megadictya, 301.

melpomene, 135.

musa, 133.

nana, 136.

aphid turn, 140.

polyhymnia, 134.

radiosa, 334.

setosa, 135.

spinulosa, 332.

sulcata, 333.

terpsichore, 137.

testudo, 325.

thalia, 137.

Stylosphsera —

urania, 134.
STYLOSPH.SRIDA, 121.
Stylospira, 512.

arachnia, 513.

dujardinii, 513.

heliospira, 512.
Stylospongia, 584.

huxleyi, 585.
Stylospongidium, 586.

geddesii, 585.
Stylostaurus, 157.

caudatus, 157.

gladiatus, 158.
Stylotrochiscus, 583.
Stylotrochus, 583.

arachiiius, 583.

cratieulatus, 583.

geddesii, 585.

helianthus, 584.

heteraeanthus, 584.

hnxleyi, 585.

rhabdostylus, 584.
Stypolarcns, 614.

spongiosus, 614.
Styposphsera, 86.

spongiacea, 87.

spumacea, 87.

stupacea, 87.

Taurospyris, 1058.

bovina, 1058.

cervina, 1058.
Tessarasparium, 835.
TESSARASPIDA, 830.
Tessaraspidium, 838.

quadratum, 838.
Tessaraspis, 835.

arachnoides, 836.

circularis, 837.

concreta, 838.

diodon, 837.

elegans, 844.

icosastaura, 846.

hexagonalis, 836.

irregularis, 838.

micropora, 827.

pentagonalis, 836.

quadrata, 838.

quadriforis, 837.

rotunda, 838.

tetragonalis, 836.

trigonalis, 836.
Tessarastrum, 547.

brunonis, 548.

democriti, 548.

spinozse, 546.

sti-aussii, 547.
Tessarospyris, 1045.

clathrobursa, 1045.

REPORT ON THE RADIOLARIA.

1799

Tessarospyris —

nucifonnis, 1046.

seminulura, 1046.
Tetracorethra, 1044.

mirabilis, 1044.
Tetracoronis, 981.
Tetracranastrum, 552.
Tetracubns, 994.
TETRACYRTIDA, 1434.
Tetrahedrina, 1238.

pyramidalis, 1238.

pyriformis, 1238.

quadricornis, 1239.
Tetralacorys, 1370.
Tetraphormis, 1243.
Tetraplagia, 911.

abietina, 912.

geometrica, 911.

phsenaxonia, 911.
TETRAPLAGIDA, 941.
Tetraplecta, 923.

pinigera, 924.

quadricornis, 924.

tetrahedra, 923.
TETRAPIECTIDA, 923.
Tetrapyle, 645.

cardiopyle, 646.

circopyle, 645.

circularis, 645.

cladacantha, 648.

crueiata, 647.

dodecaceros, 649.

fusiformis, 646.

nephropyle, 645.

octacantha, 648.

pleuracantha, 646.

pluteus, 649.

polyacantha, 1761.

quadricornis, 647.

quadrigata, 648.

quadriloba, 645.

staurophora, 647.

tetraoantha, 647.

transversa, 646.

turrita, 649.
Tetrapylonium, 657.

armatum, 659.

octacanthum, 658.

pantellipticum, 658.

quadrangulare, 658.

reniforme, 658.
Tetrarrhabda, 1044.
Tetrasolenia, 113.

quadrata, 113.

venosa, 114.
TETRASPH.ERIDA, 52.
TETRASPYEIDA, 1043.
Tetraspyris, 1043.

calcarata, 1045.

cubica, 1044.

Tetraspyris —

scoparia, 1045.

stephanium, 1044.

tetracorethra, 1044.
Tetroniscus, 487.
Tkamwospyris, 1070.

thamnopodia, 1071.
Thalassicolla, 18.

acufera, 46.

australis, 20.

cavispicula, 1551.

maculata, 21.

melacapsa, 21.

nucleata, 20.

papillosa, 22.

pelagica, 23.

pellucida, 19.

punctata, 25.

sanguinolenta, 22.

spumida, 19.

zanclea, 19.
Thalassicollarium, 18.
THALASSICOLLIDA, 10.
Thalassicollidium, 20.
Thalassolampe, 16.

margarodes, 16.

maxima, 17.

primordialis, 13.
Thalassophysa, 21.

papillosa, 22.

pelagica, 23.

sanguinolenta, 22.
Thalassopila, 17.

cladococcus, 17.
Thalassoplancta, 36.

brevispicula, 36.

cavispicula,, 1551.

longispicula, 36.
Thalassosphsera, 31. ,

belonium, 31.

bifurca, 33.

rhaphidium, 31.
THALASSOSPH.ERIDA, 29.
Thalassoxanthium, 32.

bifurcum, 33.

cervicorne, 33.

furcatum, 33.

hexactinium, 32.

medusinum, 32.

octoceras, 34.

ovodimare, 34.

punctatum, 34.

triactinium, 32.

triradiatum, 32.
Thecosphsera, 78.

sequorea, 80.

capillacea, 81.

diplococcus, 81.

dodecactis, 82.

entactinia, 81.

Thecosphsera —

favosa, 79.

floribunda, 79.

icosactis, 82.

inermis, 80.

maxima, 82.

medusa, 80.

micropora, 81.

phaenaxonia, 79.

triplodictyon, 79.
THECOSPH.BRIDA, 78.
Theocalyptra, 1397.

cornuta, 1398.

discoides, 1398.

orci, 1397.

veneris, 1397.
Theocampana, 1422.
Theocampe, 1422.

cassis, 1424.

collaris, 1425.

costata, 1426.

cryptocephala, 1426.

eryptoprora, 1423.

ehrenbergii, 1422.

geminata, 1425.

megalopora, 1425.

nucula, 1423.

ovulum, 1424.

pirum, 1423.

sphserothorax, 1424.

stenostoma, 1423.

versipellis, 1425.
Theoeentra, 1424.
Theocapsa, 1426.

aldrovandi, 1428.

aristotelis, 1427.

bserii, 1430.

cuvieri, 1430.

darwinii, 1431.

democriti, 1427.

forskalii, 1429.

galeni, 1427.

gessneri, 1428. i

lamarckii, 1430.

linnaii, 1429.

malpighii, 1428.

miilleri, 1431.

pallasii, 1429.

plinii, 1427.

rathkei, 1430.

sarsii, 1431.

schwannii, 1431.

wolffii, 1429.

wottonis, 1428.
Theocapsetta, 1426.
THEOCAPSIDA, 1426.
Theocapsilla, 1427.
Theocapsomma, 1428.
Theocapsura, 1430. .,
Theoconus, 1399.

1800

THE VOYAGE OF H.M.S. CHALLENGES.

Theoconus —

segeus, 1400.

an i plus, 1402.

ampullaceus, 1402.

ariadnes, 1402.

campauulatus, 1400.

dionysius, 1402.

ficus, 1403.

jovis, 1401.

junonis, 1401.

lateraa, 1403.

longicornis, 1401.

orthoconus, 1400.

zancleus, 1399.

zanguebarieus, 1400.
Theocorax, 1399.
Theocorbis, 1401.
THEOCORIDA, 1396.
Theoeoronium, 1415.
Theocorusca, 1407.
Theoeorys, 1414.

alauda, 1418.

ampullacea, 1402.

apollinis, 1418.

attenuata, 1417.

bachabunda, 1417.

cretica, 1415.

diamo, 1416.

jlcus, 1403.

hyalothorax, 1417.

longicornis, 1370.

martis, 1419.

mercurii, 1419.

minervae, 1419.

obliqua, 1417.

ovata, 1416.

plutonis, 1416.

scolopax, 1416.

sphaeropbila, 1418.

tnberculata, 1419.

turgidula, 1415.

veneris, 1415.
Theocorypha, 1405.
Theocorytlnum, 1416.
THBJCYRTIDA, 1395.
Theocyrtis, 1405.

aspera, 1408.

barbadensis, 1406.

cylindrica, 1406.

elegans, 1406.

macroceros, 1407.

microtheca, 1407.

cenojihila, 1408.

paupera, 1407.

prosei-pinse, 1408.

ptyuhodes, 1408.

trachelius, 1405.
Tlieodiscoma, 414.
Theodiscura, 415.
Theodiscus, 413.

Theodiscus —

christianus, 414.

divinus, 414.

nirwana, 415.

trinitatis, 414.

vanitatis, 415.
Theopera, 1357.

chytropns, 1358.

cortina, 1358.

fusiformis, 1357.

luscinia, 1358.

prismatica, 1357.

pyramis, 1357.
THEOPEKIDA, 1354.
Theophana, 1394.

corona, 1394.

noaaria, 1395.
THEOPH^NIDA, 1393.
THEOPHORMIDA, 1366.
Theophormis, 1366.

eallipilinm, 1367.

eruciata, 1367.

medusa, 1367.

senaria, 1368.
THEOPILIDA, 1315.
Theosyringium, 1409.

pipetta, 1409.

siphouium, 1409.

tibia, 1409.

tubnlus, 1411.
Theopilium, 1321.

cranoides, 1322. '

tricostatum, 1322.

triradiatum, 1322.
Theopodium, 1328.

pyramidale, 1328.

tricostatum, 1328.
THEROSPYRIDA, 1055.
Therospyris, 1058.

canis, 1058.

felis, 1059.

leo, 1059.
Tholartus, 663.

isocolus, 664.

paniscus, 664.

sagitta, 665.

tricolus, 664.

tripanis, 665.
Tholocubus, 677.

tessellatus, 677.

te.^seralis, 678.

tesserarius, 677.
Tholodes, 665.

cupula, 665.
Tholoma, 671.

metallasson, 672.

quadrigeminum, 672.
THOLONIDA, 660.
Tholonium, 678.

bicubicum, 678.

Thelonium —

ellipticum, 679

hexonium, 679.

sphsericum, 679.

sphiEronium, 679.
Tholospira, 699.

cervicornis, 700.

dendrophora, 700.

hystrix, 700.

nautiloides, 699.

spinosa, 696.
Tholospirema, 699.
Tholospironium, 700.
THOLOSPYRIDA, 1077.
Tholospyridium, 1079.
Tholospyris, 1078.

cupola, 1080.

fsnestrata, 1079.

galeata, 1079.

ramosa, 1079.

tripodiscus, 1079.
Tholospyrium, 1078.
Tholostauras, 670.

cruciformis, 670.

dodecabelos, 671.

octobelonis, 671.

polybelonis, 671.

quadrigatus, 670.

tetrabelonis, 671.
Tholothauma, 682.

ellipsoides, 682.
Thoracaspis, 862.

bipennis, 862.

circopora, 862.

ellipsoides, 862.

nephropora, 862.
Thyrsocyrtis, 1350.

anthvphora, 1491.

arborescens, 1350.

bachabunda, 1417.

bromia, 1349.

dionysia, 1402.

furcata, 1351.

jacchia, 1402.

lycm, 1348.

amophila, 1408.

radicata, 1351.

nticulata, 1274.

rhizodon, 1350.

rhizopodium, 1351.

rhizopus, 1351.

trifida, 1352.

TlAROSPYRIDA, 1078.
Tiarospyris, 1082.

amphora, 1083.

galea, 1082.

mitra, 1082.

pervia, 1082.
Toxarium, 995.

bifurcum, 997.

n

REPORT ON THE RADIOLARIA.

1801

Toxarium —

circospyris, 995.

constrictum, 996.

cordatum, 996.

costatum, 997.

furcatum, 997.

pedatum, 997.

subcirculare, 996.

thorax, 996.
Toxellinm, 995.
Toxidium, 996.
Toxonium, 997.
TREMATODISCIDA, 491.
Trematodiscus, 492.

concentricus, 492.

ellipticus, 494.

flwtnlla, 493.

haeckclii, 1763.

heliarides, 496.

heterocyclus, 494.

macroporus, 493.

microporus, 493.

orlnculatus, 492.

sorites, 493.

soritoides, 1762.
Triacartus, 1436.
Triactinosphcera, 590.

zittelii, 590.
Triactiscus, 432.

tricuspis, 432.

tripodiscus, 432.

tripyramis, 432.
Tribono«phsera, 98.

eentripetalis, 98.
Triceraspyris, 1029.

arborescens, 1032.

corallorrhiza, 1031.

cortiniscus, 1030.

damaecornis, 1032.

didicerog, 1030.

furcata, 1031.

gazella, 1031.

giraffa, 1031.

longicornis, 1032.

maniculata, 1031.

tripodiscus, 1030
Trichogromia, 1661.

hirsuta, 1661.
Tricircarium, 985.
Tricirconium, 986.
Tricolocampe, 1411.

amphizona, 1413.

arcta, 1414.

cingulatft, 1414.

cylindrica, 1412.

doliolum, 1414.

panthera, 1413.

polyzona, 1412.

pupa, 1412.

stenozona, 1413.

(ZOOL. CHALL. EXP. — PART XL.-

Tricolooampe —

urnula, 1413.
Tricolocampium, 1412.
Tricolocamptra, 1413.
Tricolocapsa, 1431.

brownii, 1433.'

decandollei, 1433.

dioscoridis, 1432.

linnai, 1432.

schleidenii, 1433.

theophrasti, 1432.
Tricolocapsium, 1433.
Tricoloeapsula, 1432.
Tricolospyris, 1097.

baconiana, 1098.

kantiana, 1098.

leibnitziana, 1098.

newtoniana, 1098.
Tricraiiastnim, 541.

wyvillei, 551.
Trictenartus, 1440.
Tricyclarium, 987.
Tricyclidium, 984.

dictyospyris, 984.

semantrum, 985.
Tricyclonium, 987.
TRICYRTIDA, 1313.
Tridictyopus, 1145.

conulus, 1145.

elegans, 1145.

vatillum, 1145.
Trigonactinium, 472.
Trigonactura, 471.

lanceolata, 472.

pythagorse, 471.

rhopalastrella, 471.

triacantha, 472.

trigonobrachia, 472.

trigonodisous, 472.

trixiphos, 473.
Trigonacturium, 471.
Trigonastrum, 539.

gegenbauri, 539.

krohnii, 539.

regulare, 539.
Trigonocyclia, 464.

triangularis, 464.
Triodiscus, 566.

lenticula, 566.

trigonus, 567.

spinosus, 567.
Triolena, 564.

hexabelone, 564.

primordialis, 564.

tribelone, 564.

trigonalis, 564.

trispinosa, 564.
Trioniscus, 486.
Triopyle, 564.

circulus, 565.
1887.)

Triopyle —

cordigera, 565.

hexagona, 565.

renigera, 565.

spinigera, 566.

trigona, 565.
TRIOPYLIDA, 563.
TRIOSPH.SRIDA, 52.
Triospyridium, 1032.
Triospyris, 1030.
Triospyrium, 1030.
TRIOSTEPHIDA, 967.
Triostephus, 983.
Tripilidium, 1140.

cladopodium, 1142.

clavatum, 1141.

cortiua, 1140.

costatum, 1141.

dichopodium, 1142.

elongatum, 114?.

hemisphsericum, 1140.

lychnocanium, 1141.

ovatum, 1141.
Triplagia, 908.

horizontalis, 909.

primordialis, 909.

triradialis, 909.
TRIPLAGIDA, 908.
Triplecta, 921.

triactis, 922.

triangulum, 921.
TRIPLECTIDA, 921.
TP.IPLOZONAKIA, 656.
TRIPOCALPIDA, 1133.
Tripocalpis, 1135.

cortinaris, 1137.

galea, 1136.

plectaniscus, 1136.

tricostata, 1136.

triserrata, 1136.
Tripocoronis, 981.
Tripocubus, 994.
TRIPOCYRTIDA, 1192.
Tripocyrtis, 1201.

challengeri, 1231.

plagoniscus, 1201.

plectaniscus, 1202.

tripodiscus, 1202.
Tripodictya, 505.

triacantha, 505.

tribelonia, 505.

trigonaria, 505.
Tripodiscinus, 1143.
Tripodisculus, 1144.
Tripodocorys, 1142.
Tripodonium, 1137.

campanulatum, 1137.

ovatiim, 1137.
Tnpodiscium, 1143.

campanula, 1144.

Rr226

1802

THE VOYAGE OF H.M.S. CHALLENGER.

Tripodiscium —

clavatum, 1143.
furcatum. 1144.
ovatum, 1143.
ramosum, 1144.
sphserocephalum, 1144.
tristylospyris, 1143.
Tripospyrantha, 1025.
Tripospyrella, 1026.
TRIPOSPYEIDA, 1025.
Tripospyris, 1025.

capitata, 1025.
clavata, 1028.
conifera, 1027.
cortina, 1025.
cortiniscus, 1026.
diomma, 1026.
eucolpos, 1029.
euscenium, 1147.
furcata, 1021.
lirxomma, 1028.
semantidium, 1029.
semantis, 1026.
semantrum, 1027.
tessarorama, 1028.
tribrachiata, 1029.
triomma, 1026.
triplecta, 1027.
Tripospyrissa, 1027.
Tripospyromma, 1028.
Tripterocalpis, 1137.

conoptera, 1138.
ogmoptera, 1138.
phylloptera, 1138.
TRIPYLEA, 1521.
Trisolenia, 113.

megalactis, 114.
zanguebarica, 97.
Trissocircus, 985.

binellipsis, 985.
globus, 986.
lentellipsis, 985.
octahedrus, 986.
octostoma, 986.
TRISSOCYCLIDA, 982.
Trissocyclus, 986.

sphaeridium, 987.
stauroporus, 987.
triaxonius, 987.
Trissopilium, 1138.

lithomelissa, 1139.
tetraplecta, 1139.
Tristephaniscus, 984,
Tristephanium, 982.

dimenaivum, 983.
hertwigii, 983.
octopyle, 983.
quadricorne, 984.
Tristylocorys, 1140.
Tristylospyris, 1032.

Tristylospyris —

clavipes, 1033.
furcata, 1034.
palmipes, 1033.
ramosa, 1034.
scaphipes, 1033.
triceros, 1033.
tripodiscium, 1034.
Tristylospyrula, 1033.
Tristylospyrium, 1034.
Trizonium, 637.

amphibelonium, 638.
constrictum, 637.
decabelonium, 639.
dodecabelos, 640.
hexabelonium, 639.
hexagonium, 638.
octobelonium, 639.
octogoniuui, 638.
pleurobelonium, 638.
staurobelonium, 639.
tricinctnm, 637.
TROCHODISCIDA, 412.
Trochodisculus, 417.
Trochodiscus, 417.

cenophacus, 417.
cingilluin, 419.
echiniscus, 418.
medusinus, 417.
odontotrochus, 418.
Solaris, 418.
stellaris, 418.
Trypanosphsera, 109.
coronata, 110.
dentata, 110.
terebrata, 110.
transformata, 111.
trepanata, 110.
TYMPANIDA, 987.
Tympanidium, 1003.

barbadense, 1004.
binoctonum, 1004.
foliosum, 1003.
spinosum, IOCS,
staurooircum, 1004.
Tympaniscus, 1001.
bipes, 1001.
coroua, 1001.
dipodiscus, 1001.
dizonius, 973.
dodecaster, 1002.
fibula, 1002.
quadrupes, 1002.
tripodiseus, 1002.
Tympanura, 1003.
Tympanomma, 1004.
Tuscarantha, 1706.
Tuscaretta, 1707.
Tuscaridium, 1709.

cygneum, 1709.

Tusoaridiura —

lithornithium, 1710
Tuscarilla, 1708.
Tuscarora, 1706.

belknapii, 1708.

bisternaria, 1706.

cygneum, 1709.

murrayi, 1706.

porcellana, 1708.

tetrahedra, 1707.

tubulosa, 1707.

wyvillei, 1707.

TuSCARORIDA, 1702.

Tuscarusa, 1707.

medusa, 1709.

Urocyrtis, 1762.

amalise, 1762.
emmae, 1762.
stephauii, 1762.

Xanthiosphfera, 119.

capillacea, 119.

erinacea, 120.

lappacea, 120.
Xiphacantha, 758.

alata, 761.

.ancorata, 760.

eiliata, 761

cruciata, 754.

crucifera, 759.

emarginata, 759.

falcata, 759.

foliosa, 754.

macroptera, 760.

murrayana, 763.

pectinate, 757.

platyptera, 761.

quadridentata, 758.

serrata, 757.

spinulosa, 759.

stauroptera, 760.

trigonoptera, 760.
Xipliacanthidium, 760.
Xiphacanthonium, 758.
Xiphatractus, 332.

armadillo, 332.

chlamydophorus, 333.

dasypus, 333.

euphractus, 332.

glyptodon, 334.

radiosus, 334.

spinulosus, 332.

sulcatus, 333.
Xiphodictya, 503.

amphibelonia, 503.
auiphirrhopalia, 504.
staurospira, 504.
heliospira, 504.
Xiphoptera, 777.

REPORT ON THE RADIOLARIA.

1803

Xiphoptora —

dodecactena, 778.

icosactena, 778.

tessaractena, 778.
Xiphosphaera, 123.

astrsea, 126.

bipolaris, 297.

ceres, 126.

clavigara, 126.

euphrosyne, 124.

flora, 125.

gsea, 123.

gigantea, 125.

hebe, 127.

luna, 123.

juno, 125.

maxima, 124.

pallas, 124.

planeta, 123.

venus, 123.

vesta, 126.
Xiphospira, 504,

XlPHOSTYLIDA, 122.

Xiphostylus, 127.
alauda, 128.
alca, 130.
alcedo, 127.
anhinga, 128.
' ardea, 131.
cuculus, 129,
edoUus, 130.
emberiza, 131.
falco, 130.
gallus, 128.
motacilla, 127.
phasianus, 127.
pieus, 129.
trochilus, 129.
trogon, 129.

ZONARIDA, 682.
Zonarium, 684.

octangulurn, 685.

Zonarium —

quadrigatum, 685.

quadrispinum, 685.

tetratholium, 685.
Zonaspis, 833.

sequatorialis, 834.

cingulata, 834.

fragilis, 833.
Zonidium, 687.

octostylium, 688.

octotholium, 688.
Zoniscus, 686.

hexathalamius, 686.

hexatholius, 687.

octacanthus, 687.

rectangulus, 686.

tetracanthus, 687.
ZONODISCIDA, 411.
Zonodiscus, 412.

saturnalis, 412.
Zygacantha, 746.

complanata, 748.

compressa, 747.

costata, 746.

dichotoina, 747.

dicopa, 748.

foliacea, 748.

furcata, 747.

lanceolata, 746.

semicompressa, 748.
Zygacantharium, 746.

ZYOACANTHIDA, 742.
Zygacanthidium, 747.
Zygacanthonium, 748,
ZYGARTIDA, 397.
Zygartus, 401.

chrysalis, 401.

doliolum, 401.

larvalis, 398.

virginis, 369.
Zygocampe, 399.

chrysalidium, 400.

corasium, 400.

Zygocampe —

pupula, 399.
ZYGOCAMPIDA, 392.
Zygocircus, 945.

acacia, 1947.

butschlii, 948,

dodecanthus, 947.

hexagonus, 947.

pentagonus, 946.

polygonus, 947.

productus, 958.

rhombicus, 946.

sagittalis, 946.

tetragonus, 946.

trigonus, 946.

triquetrns, 347.
ZYOOCTRTIDA, 1015.
ZYGOSPYRIDA, 1021.
Zygospyris, 1055.

equus, 1056.

quadrupes, 1055.
Zygostaurus, 774.

amphithectus, 774.

arcuatus, 774.

caudatus, 775.

certmtus, 775.

frontalis, 775.

longicomis, 774.

sagittalis, 775.
ZYGOSTEPHANIDA, 970.
Zygostephaniscus, 972.
Zygostephanium, 972.

constrictum, 973.

dizonium, 973.

paradictyura, 973.
Zygostephaaus, 970.

bicornis, 972.

dissocircus, 971.

miilleri, 971.

ramosus, 971.

reniformis, 972

serratas, 971.

violina, 972.

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