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V

BRITISH HYDEOID ZOOPHYTES,

VOL. I.

EndcinJrium rameum, Pallas.

'j sf

HISTORY

OF THE

BRITISH HYDKOID ZOOPHYTES.

BY

THOMAS HINCKS, B.A.

IN TWO VOLUMES.

VOL. I.— TEXT.

LONDON:

.10HN VAN VOORST, PATERNOSTER ROW.

MDCCCLXVIII.

" THAT which we foolishly call vastness is, rightly considered, not more
wonderful, not more impressive, than that which we insolently call little-
ness."— BUSKIN.

R E F A C E.

IT is not necessary that I should enter into any
explanation of the causes that have delayed the
publication of the present work, which was designed
and announced several years since ; but I should be
ungrateful if I did not acknowledge the enduring
patience of the Publisher under trials of no ordinary
kind.

The appearance of this work cannot certainly be
accounted premature. Twenty-one years have elapsed
since the second edition of Dr. Johnston's ' History
of British Zoophytes ' was published ; and during that
period the whole aspect of his favourite science has
changed. His classification of the Hydroida has long
been in great part obsolete, while the number of known
species has been almost trebled since he wrote. Like
his predecessor, Ellis, he rendered in his day invaluable
service to Zoophytology, and gave an impulse to the
study of it, of which we are now reaping the fruits.
It should be added that there is a charm in his work,
which does not become obsolete with its science ; it

PREFACE.

will always rank, with the ' Corallines ' of Ellis,
amongst the classics of natural-history literature.
As a manual for the use of the student, however, it
has long ceased to be of value ; nor is there any work
in existence that contains a complete account of the
British Hyclroida. The place therefore is vacant,
which the present work aspires to fill. I have endea-
voured to make it a full and faithful exposition of our
present knowledge, and to do for the students of this
day what Johnston's ' History ' accomplished for those
of his own generation. It is certainly time that the
remarkable results attained since he wrote, and now
widely scattered, should be presented in a connected
form and made available for general use, and that the
difficulties should be removed which interfere with the
cultivation of one of the most delightful branches of
Natural History.

This Preface might have been very brief, had not
the kindness of many friends and fellow workers laid
me under heavy obligations, which it is a duty and a
pleasure to acknowledge ; without such cooperation,
indeed, I could not have accomplished my work.
Foremost amongst those to whom I have been in-
debted for help, it is right that I should place my
lamented friend the late Mr. Alder, one of the ablest
of British naturalists, and one of the most amiable
and upright of men. In the course of a long corre-
spondence, extending over many years, and relating
chiefly to our favourite studies, I have had the oppor-
tunity of profiting largely by his extensive knowledge,

PREFACE.

accurate observation, and sound judgment. During
the preparation of this work I have had the benefit of
his valuable opinion in many cases of difficulty, and
have often been materially assisted by his cautious
wisdom and remarkable skill in the discrimination of
species. His collection was freely placed at my ser-
vice ; and many of the figures with which this work is
enriched are engraved from his admirable drawings.

To Mr. Busk I am under peculiar obligations for
much valuable counsel and practical aid, and especially
for his kindness in placing at my disposal his large
and interesting collection of foreign Hydroida and an
extensive series of drawings.

To my friend Prof. Allman I owe my warmest
thanks for the readiness with which, out of his large
stores of knowledge, he has communicated informa-
tion that I happened to need, or favoured me with
his views on doubtful points. I am also indebted to
him for drawings of some of the species which he has
discovered. The reader of this work will understand
how much I, in common witli all zoophytologists, owe
to his writings.

Dr. Stre thill Wright has rendered me most impor-
tant service by permitting me to reproduce the figures
which illustrate his valuable papers, and by freely
communicating to me his views on some of the most
interesting questions in zoophytology.

To the Rev. A. M. Norman I am indebted for the
use of the late Mr. Barlee's collection of Hydroida,
including many Shetland acquisitions, and for the

PREFACE.

opportunity of examining specimens obtained by him-
self in the course of his extended dredgings.

Mr. J. Gwyn Jeffreys has kindly supplied me with
a quantity of zoophytes procured during one of his
famous Shetland cruises, amongst which were one or
two most beautiful species new to science.

Mr. C. W. Peach, who was a valued contributor to
Dr. Johnston's ' History,' and who is an enthusiastic
worker still, has come to my assistance with an ample
list of habitats, and has also contributed some inter-
esting specimens.

My acknowledgments are further due to Professor
Wyville Thomson for some exquisite drawings which
have been engraved for this work ; to Dr. Collingwood
for a list of the zoophytes found in the neighbour-
hood of Liverpool, and notes on some of the species ;
to my friend Mr. E. W. H. Holdsworth for his
interesting observations on Cladoncma ; to Mr. George
Hodge for the use of figures and the communication
of specimens ; to Mr. Leipner for some very skilfully
mounted specimens of Campanularian and other zoo-
phytes; and to Mr. G. S. Brady for Hydroida obtained
in Connemara.

I have also to thank Professor Sars and Professor
Van Beneden for their great courtesy and kindness in
forwarding to me copies of their publications.

In the preparation of the plates I have had the zea-
lous cooperation of Mr. Tuffen West, who has spared
no pains in the execution of the engravings, and whose
practical acquaintance with the subjects delineated,

PREFACE.

combined with his well-known artistic skill, has en-
abled him to produce a most satisfactory result.

One point in the work itself requires a word of
explanation. It has been impossible, from the very
nature of the objects treated of, to make the specific
descriptions as brief as I could have desired. I have
therefore printed in Italics the leading and distinctive
characters, so that the peculiarities which separate
each species from others may be recognized at a

glance.

I trust that this work may facilitate the study of
one of the most charming branches of Natural History,
and so tend in its degree to foster a taste which, I
can testify from experience, is an unfailing source of
delight, and affords the most welcome relief and
refreshment amidst the cares and harder duties of
life.

T. H.

Great Malvern,
November 20th, 1868.

Plumularia haledoides (young!

CONTENTS.

PAGE

INTRODUCTION ........................................ i

TERMINOLOGY OP THE HYDROIDA .................... i

THE HYDROID COLONY .............................. v

REPRODUCTION .................................... xx

RATE OF GROWTH. PHOSPHORESCENCE .............. xliii

GEOGRAPHICAL DISTRIBUTION ........................ xlv

METHOD OP COLLECTING THE HYDROIDA .............. xlviiii

BIBLIOGRAPHY .................................... lii

DICHOTOMOUS TABLES " .............................. lii

CLASSIFICATION .................................... Ivii

Suborder I. ATHECATA ................................ 1-135

Family CLAVID^E ............................... 1-18

„ HYDRACTINIID^E .......................... 18-27

„ PODOCORYNID^: ......................... 27-35

,, LARIDJE .................................. 35-37

„ CORYNID.33 ................................ 37-61

„ RTAURIDIIDJE .............................. 61-69

CL.VVATELLIDJE ............................ 69-75

„ MYRIOTHELIP.T: .......................... 75-78

„ ............................ 79-87

„ ATBACTYLIDJK ........................... 87-113

„ TUBULABIID^K ............................ 114-131

3 72 SO

CONTENTS.

.Suborder II. THECAPHORA 137-308

Family CAMPANULARIID^E 137-185

„ CAMPANULINIDJE 186-195

„ LEPTOSCYPHID^E 196-198

„ LAFOEIDJE . . ; 198-215

„ TRICHYDRIDJE 215-218

„ COPPINIID^E 218-220

„ HALECIID^E 220-233

„ SERTULARIIDJE 233-279

„ PLUMULARIIDJE 279-308

Suborder III. GYMNOCHROA 309-31G

Family HYDRIDE 309-316

APPENDIX 317-325

LIST OF WORKS ON THE HYDROIDA 327-328

INDEX TO THE WOODCUTS 331-334

INDEX 335-338

INTRODUCTION,

A GENERAL sketch of the structure of the Hydroida, and
the history of their reproduction and development, is a fit-
ting prelude to the study of our British species. It would
be impossible, in a systematic work like the present, to dis-
cuss at length the many interesting and difficult questions
that meet the student in this province of zoology. It will
rather be my aim to convey an accurate idea of the form
of structure that characterizes this group of animals, and
of the striking facts of the Hydroid life-history.

As a preliminary, it will be necessary to define the de-
scriptive terms employed in this work.

TERMINOLOGY.

I have endeavoured to simplify in this department as
much as is consistent with precision, believing that a cum-
brous and difficult terminology is the bane of science. As
uniformity of practice is clearly desirable, and much con-
fusion arises from the use of terms in different senses, I
have made only those changes that seemed to be absolutely
necessary, and have adopted the terms that have obtained
most currency in the higher literature of the subject.

A precise terminology is no doubt of great value ; but

a

11 INTRODUCTION.

to burthen technical language with a multitude of harsh-
sounding Greek compounds is to check, and not to aid, the
cultivation of science. The aim should be to combine
definiteness with simplicity, as far as possible.

The following List includes the principal terms with
which the student of the Hydroida should be familiar : —

ZOOID. — Any one of the principal elements, more or less
independent, that make up the complex individuality of
the zoophyte, — e.g. the polypite, the reproductive body,
whether fixed or free, &c.

POLYPITE. — The alimentary or nutritive element of the
Hydroid colony, consisting of a digestive sac, with a ter-
minal opening (mouth) and organs of prehension (ten-
tacles). Occasionally the adult zoophyte consists of a
single polypite, as in Myriothela, Corymorpha, and Hydra ;
but generally a large number, the product of successive
buddings, are organically united, so as to form a compo-
site and plant-like structure.

. — The common flesh or trunk, which unites
and binds together the polypites in a compound zoophyte.
The following parts must be distinguished in it : — the stem,
which is sometimes simple and sometimes branched, and the
adherent base* or stolon, which roots the zoophyte to the
surface on which it grows. The latter is generally filiform
and reticulated ; but in some cases it occurs as a solid,
chitinous crust (Hy dr actinia) .

POLYPARY. — The chitinous f sheath or tube which encloses

* The former of these is the hydrocaulus of sortie writers, and the latter
the hydrorhiza.

t Chitine is a suhstance resembling horn, but differing from it in chemical
composition.

INTRODUCTION. Ill

the coenosarc, to a greater or less extent, in all (?) the fixed
Hydroida. It varies in the degree of development, some-
times investing the whole of the cosnosarc, and sometimes
only a small portion of it. It usually forms a solid cover-
ing, but in some cases is a mere membranous film.

HYDROTHECA or CALYCLE. — The chitinous receptacle in
which the polypites are lodged in one of the Hydroid sub-
orders ( Thecaphora) . The term cell has been commonly
applied to this portion of structure ; but as this word is
now generally used in physiological science with a totally
different meaning, it will be more convenient to dispense
with it here.

GONOPHORE. — The bud in which the reproductive ele-
ments are formed. It consists of an external envelope
(ectotheca), enclosing either a fixed generative sac, between
the walls of which the ova and spermatozoa are developed,
or a free sexual zooid*.

GONOZOOID. — The sexual zooid, whether fixed or free ;
the gonophore minus the ectotheca. In some genera
(e. g. Clavatella and Corymorpha) the gonozooids are
destitute of an ectothecal covering at all stages of their
development.

* A somewhat different meaning is given to the term gonophore from that
which it bears in the works of Prof. Allman, by whom it was introduced. A
little uncertainty, it seems to me, connects itself with his use of the word.
He has denned the gonophores to be " certain buds of a peculiar structure,
destined for the formation and protection of the generative elements." Of
these buds an ectotheque or protective envelope is, in a large proportion of
cases, an essential part ; and the contained sexual zooid, when free, makes its
escape from this outer sac, which then withers away. Now, as employed by
Allman, the gonophore is sometimes the reproductive bud with its ectotheca,
and sometimes the contained zooid, whether fixed or free. To me the gono-
phore is the whole bud, and the sexual zooid developed in it, whether as a
fixed sac or a floating polypite, is the gonosooid.

a2

IV INTRODUCTION.

SPOROSAC. — The generative sac.

GONOTHECA or CAPSULE. — The chitiiious receptacle,
within which the gonophores are produced, in the sub-
order Thecaphora.

CORBULA. — The protective case which shelters the repro-
ductive capsules in the genus Aglaophenia. (Woodcut,
fig. 37, page 308.)

UMBRELLA or SWIMMING-BELL. — The contractile disk, by
means of which the medusiform gonozooid propels itself.

MANUBRIUM. — The hollow body terminating in a mouth,
which is suspended from the top of the umbrella, and
hangs free in its cavity.

VELUM. — The delicate membrane which partially closes
the opening of the swimming-bell.

LITHOCYSTS. — Small sacs developed on the margin of
the swimming-bell, in certain genera, and containing
refractile spherules. They are probably organs of sense.

PLANULA. — The usual form of the Hydroid embryo.

TROPHOSOME. — The whole company of alimentary zooids
associated in a Hydroid community.

GONOSOME. — The sexual zooids of the community.

ECTODERM. — The external membrane or layer of the
body-substance amongst the Crelenterata.

ENDODERM. — The internal layer of the body-substance.

NEMATOCYSTS or THREAD-CELLS. — Minute sacs imbedded
in the body-substance containing delicate projectile threads.

INTRODUCTION. V

PALPOCIL. — A rigid, hair-like process, occurring on the
tentacles of some of the Hydroida, and probably an organ
of touch.

THE HYDROID COLONY.

In a few cases the adult Hydroid consists of a single
polypite ; but generally many are organically united
and form a colony or community. Associated life is the
rule, and solitary existence the rare exception. Amongst
the animals that compose the present order gemmation is
universal, and by successive buddings the complex plant -
like structure is rapidly evolved from the primary polypite,
which is the product of the egg. Even in Hydra, which is
a solitary being, the vegetative power is active ; but the
buds, which are produced in profusion, are thrown off
instead of being retained in permanent connexion with the
parent stock.

The Hydroid colony, which may include its thousands
of polypites, as well as a large company of reproductive
zooids, is the result, like the tree, of a continuous process
of budding, and, whatever its extent, has originated in
a single polypite. The analogies, indeed, between zoo-
phyte-life and plant-life are numerous and striking ; and
we shall best illustrate and explain many points in the
history of the Hydroida by a reference to the facts of the
vegetable world.

Every Hydroid colony consists of two parts (which may
be considered separately) — the coenosarc or common con-
necting substance, and the zooids held in organic union by
it, which discharge different functions in the service of the
commonwealth.

The coenosarc is a fleshy tube (a thread of animal sub-
stance hollowed out in the centre) which now appears as

VI INTRODUCTION.

a trailing fibre adherent to some body and rooting the
whole colony to its place, now as a simple or branching
trunk supporting the zooids, and multiplying and renewing
them. It is composed of two layers, an outer (ectoderm)
and an inner (endoderm) , which enter into every portion of
the structure. The endoderm lines the whole of the body-
cavity, and is chiefly concerned with nutrition : the ecto-
derm is much more susceptible of modification, and gives
rise to many important structures. Between these two
primitive layers a third is sometimes interposed, described
by Allman and Wright as a muscular coat, composed of
longitudinal fibres, and by Reichert as " a supporting
lamella — a sort of inner skeleton." It has been observed
in the body of the polypites, and, if muscular, will explain
the rapidity with which they retract themselves*. In most
cases the ccenosarc is partially or wholly protected by a chiti-
nous covering (polypary) , which is a secretion from its outer
layer. In many families the polypary invests the whole of the
soft animal substance, and expands into elegant cups or caly-
cles around the body of the polypites ; and we have thus a
cast of the composite structure in chitine, which, in the
disposition of its parts and its general aspect, bears a close
resemblance to a plant.

In other families the polypary is less developed, merely
investing the stolonic network and the base of the poly-
pites, or also clothing the trunk and branches, but never
forming a true calycle. The Hydra alone, if we except the

* Vide a paper by Dr. T. Strethill Wright on Hydractinia echinata, Edinb.
N. P. Journ. N. S. for April 1857, paragraph 21. Also a paper by Eeichert
in the ' Monatsbericht der Akad. der Wissenchaft. zu Berlin ' for July 1866.

For the histology of the Hydroicla, the student should consult Kolliker's
' Icones HistologicaV part ii.

INTRODUCTION. Vll

floating members of the order, is totally destitute of a poly-
pary.

Through the tubular cavity of the coenosarc the nutrient
matter, elaborated within the stomachs of the polypites,
circulates, reaching every portion of the structure and
supplying the elements needed to maintain the health and
growth of the whole.

The circulation is of the simplest kind : a stream, bearing
along with it a multitude of restless granules of various
sizes, issues from the stomachs of the polypites and rushes
through the cavity of the coenosarc, pervading every portion
of the organism. After flowing downward for some time,
there is a pause in the circulation, and then the current
rushes back with great impetuosity, and, once more entering
the stomachs of the polypites, mingles with the contents.
A busy ferment takes place for some seconds in the diges-
tive sac, the larger particles hurrying to and fro amidst
the contained mass of food, until at length the efflux again
commences. The inner surface of the ccenosarc is covered
with vibratile cilia, and these seem to be the chief agents
concerned in maintaining the flow of the currents.

Within the buds, which pullulate at certain points from
the common substance, and are developed into new poly-
pites, there is always a great aggregation of the nutrient
particles and a remarkable activity amongst them. They
crowd the cavity of the nascent polypite, and supply, as it
were, the building-material that is needed for the extension
of the structure.

The coenosarc of the zoophyte may be likened to the
trunk, branches, and roots of the tree, regarding the latter
merely as a means of attachment to the soil. The zooids
which it supports and binds together in one organic whole

Vlll INTRODUCTION.

may be compared with the leaf-buds and flower-buds of
the plant.

There arc two principal classes of them — the nutritive,
or those which are concerned in obtaining and preparing
food for the commonwealth, and the reproductive, which
are charged with the propagation of the species.

The polypite or alimentary zooid, though varying in
form and colour, and in the arrangement of the prehensile
organs with which it is furnished, is always identical in
essential structure with the Hydra, the type of the class
Hydrozoa. It consists of a soft contractile body, very mu-
table in shape, the walls of which are composed of the same
elements as those of the ccenosarc, and are, indeed, a con-
tinuation of them. The interior is occupied by the diges-
tive cavity, which is not a distinct bag or sac, but a mere
hollow scooped out, as it were, in the body-substance. At
its upper extremity it terminates in an oral opening ; and
below it communicates freely with the general cavity of
the ccenosarc, and lies open to the nutrient currents that
pervade it. In some families (e. g. Campanulariidce} the
base of the stomach is connected with the common canal
traversing the stem by a narrow tubular passage, the
C( transition-piece " of Reichert *. (Woodcut, fig. i. b.}

The oral aperture is simple or somewhat lobed, and is
commonly borne on the summit of a more or less promi-
nent proboscis, which is capable of great elongation and
contraction and is remarkable for its mobility. In some
genera the proboscis is conical, in others it is trumpet- or
funnel-shaped. Amongst the Eudendriida and Campanu-

* Vide a paper "On the Contractile Substance and Intimate Structure of
the C'ampanularies, Sertularia, and Hydride" by Prof. Reichert, Monats-
bericht der Akadern. der Wissenschaft. zu Berlin, July 1866. Translated by
Dallas, Ann. N. II. for January 1867.

INTRODUCTION.

IX

lariidce it takes the latter form, and is a very conspicuous
feature. (Woodcut, fig. i. a.) It is continually changing

Fig. i.

its shape, now enormously distended, now flattened down
and with the lips thrown back, so as to form a saucer-like
disk, now opening and closing rapidly, but never long the
same. It is an admirable instrument, in conjunction with
the tentacles, for the selection and prehension of food. In
some Hydroids there is a marked constriction at the base
of the proboscis; and in the curious genus Ophiodes
(Hincks) the body is divided by a depression a little below
the tentacles into two regions, a pharyngeal and gastric.
Reichert distinguishes the narrow between the proboscis
and the stomach as " the cesophageal passage." In gene-
ral, however, the structure of the digestive sac is perfectly
simple, and no defined " regions " can be recognized.

Within the stomachs of the alimentary zooids the food
is digested and prepared for the nutrition of the whole
structure. The polypites are the feeders of the common-
wealth, and the unceasing activity of many thousands of
them in the larger species is engaged in keeping up the
necessary supplies.

X INTRODUCTION.

The tentacles or prehensile organs are ranged round the
oral extremity, or variously distributed over the surface of
the body. They are filiform appendages, more or less ex-
tensile, and always bear a formidable armature of thread-
cells, which are often aggregated in prominent groups,
so as to roughen the surface, or to give it a beaded
appearance.

The tentacle of the Hydroid is a tubular extension of the
wall of the body, and communicates at the base with its
cavity. In some cases, as in Hydra, it seems to be a simple
tube, open throughout, in which the fluids circulate freely ;
but generally the cavity is more or less obliterated, and the
tentacle presents the appearance of being septate, and par-
tially filled up by a cellular axis.

In two of the suborders under which the Hydroida are
ranged, the tentacles are disposed in a single wreath or
circle, which surrounds the base of the proboscis, and are
simply filiform ; but amongst the Athecata they exhibit
considerable variety both of form and arrangement.
They are sometimes scattered over the body of the poly-
pite, in some cases there is a slight tendency to a spiral
arrangement, in others they are placed in two remote
circles, and in one species, at least, their number is reduced
to two. Amongst the Tubulariida a large number of very
short arms immediately surround the oral extremity, and
a wreath of long slender tentacles encircles the base of
the body. In many species these organs are arranged in
two approximate series, one immediately behind the other,
so closely set as to appear like a single circlet.

In this suborder the tentacles are either slightly clavate
or capitate, or simply filiform. In some genera the capi-
tate and filiform kinds are both present.

INTRODUCTION. XI

The capitate tentacle, of which we have good examples
in Coryne and Clavatella, bears on its summit a globular
head, consisting of a collection of thread-cells — a formi-
dable battery of offensive weapons, which is brought to bear
on any passing prey. The arm is also endowed with vigo-
rous percussive power, and when its numerous poisoned
threads are brought into play, it can hardly fail to arrest
and paralyze any of the smaller creatures that may come
within its range. (Plate VII. fig. 1 6.)

The thread-cells, which bear so important a part in the
Hydroid economy, exhibit many modifications. They
occur in the ectodermal layer, and are present in as-
tonishing profusion, not only on the tentacles, but in other
portions of the structure. They consist of minute sacs
imbedded in the flesh and filled with fluid, which contain
a long and delicate thread, capable of being projected with
considerable force and inconceivable rapidity. These
threads bury themselves in any soft substance against
which they may be directed, and, it is supposed, convey
into the wound which they make some poisonous fluid.

The thread-cell is a most interesting piece of structure.
The long dart which it encloses is borne on a continuation
of the inner wall of the sac (the " sheath " of some writers,
the " axial body" of others), which is often covered with
barbs. (Woodcut, fig. iii. a.) When retracted, the thread is
spirally coiled within the cell and sometimes wound round
the sheath. (Woodcut, fig. iii. c.) Two kinds of thread-
cell are often met with on the same species. Besides the
formidable instruments with which the tentacles are armed,
large bean-shaped cells are sometimes crowded together in
immense quantities, as, for example, in the ectoderm of
the coenosarc in Hydranthea, and in the outer covering of

Xll

INTRODUCTION.

its gonophore. It is difficult to imagine what relation
these can bear to the economy of the animal.

Fig. ii. Fig. iii.

Groups of these bean-shaped cells are also present on
many of the tentacles of the latter zoophyte, a little above
the base, and form a beautiful ring of prominent pearly
bosses.

Besides the thread-cells, the arm of the Hydroid bears
another organ, which has been named by Dr. Wright the
palpocil, and which is connected, no doubt, with the sense
of touch. It consists of a long and delicate spine, springing
from a small bulb, which is buried in the ectoderm. These
palpocils or sensitive hairs are scattered over the tentacles
in many species, and over other portions of the body,
and must aid the capture of prey by giving instant notice
of the presence of any animalcule or other small creature
that may brush against them. It may be their function to
rouse the thread-cells into action.

INTRODUCTION. X11L

Besides the ordinary tentacles, peculiar appendages occur
in two genera, Cladonema (Plate XI. fig. 2) and Stauri-
dium (Plate XII. fig. 1), which I have named false tenta-
cles, and which seem to discharge the function of tactile
organs. They are filiform processes, standing out in a
single series, near the base of the body at some distance
below the arms, and at first sight might be taken for ten-
tacles deprived of their capitate extremities. They are,
however, perfectly rigid, and the tips at least are thickly
covered with the sensitive palpocils. It seems to be their
office to warn the polypite of the presence of prey, for if
one of them is touched by an animalcule in its course, the
body is immediately bent towards it, and the tentacles are
brought into play.

In a few species the tentacles are united for a portion of
their length by a very delicate membranous web. In
Ophiodes (Plate XLV. fig. 2b) it is well developed, and
forms a rather deep cup enclosing the proboscis. In this
genus it is armed with small clusters of thread-cells, which
are set round it, one in each of the spaces between the
tentacles, like so many batteries, and can discharge on the
shortest notice a multitude of poisoned darts. It is very
interesting to see the threads cast forth beyond the tips of
the tentacles, and waving about in all directions amongst
them, as if prepared to act with them in seizing and dis-
abling their prey.

The intertentacular web is of rare occurrence, and is
generally very slightly developed ; but it has a special
interest as the homologue in the polypite of the swimming-
bell in the free sexual zooid.

Amongst the Thecaphora the polypite is protected by a
calycle (Woodcut, fig. i.), within which it shelters itself by

XIV INTRODUCTION.

contracting the body and tentacles, and folding the latter
together. When in pursuit of food, it stretches itself
beyond the opening of its little dwelling, and expands its
wreath of milk-white arms, the starry blossom, as it were,
of the animal-plant.

The calycles take the most graceful forms, resembling
little chalices or vases, and are often decorated with cre-
nated or castellated borders. In many species the aper-
ture is furnished with an operculum, which opens to allow
of the passage of the polypite, and closes on its retreat. It
is a simple but very effective contrivance, and exhibits
two or three principal modifications. In some cases the
margin of the calycle is cleft into a number of pieces,
which converge and meet in a point, and form a more or
less conical lid. (Woodcut, fig 19, page 178.) In others,
the cover is a membranous extension of the walls of the
calycle, which falls into plaits or folds when the polypite
withdraws, and so roofs over the opening. Amongst the
Sertulariidce, the operculum presents another and a very
interesting form, which has its exact parallel amongst the
Protozoa. It consists of a plate or valve placed within the

Fig iv.

\

calycle, a little below the orifice, which is attached to the
interior surface on one side and seems to be a continuation

INTRODUCTION. XV

of its inner layer, and which shuts clown over the polypite
in a slanting position when it withdraws itself. When the
polypite emerges, it slowly pushes the valve back and keeps
it erect so long as it is exserted : on its retreat, which is
as quick as light, the lid flies back to its place. (Woodcut,
fig. iv. a, the operculum closed ; b, ditto open.)

Dr. Wright has described a similar structure as occurring
in the beautiful Protozoan Vaginicola valvata* ; and
amongst the terrestrial mollusca it has its analogue in the
clausium of the genus Clausilia. In some species the
operculum seems to be a simple piece attached to the
margin at one side by a kind of hinge, which falls down
over the orifice like the lid of a box.

The life of the polypites is by no means commensurate
with that of the zoophyte. They frequently perish from
various causes — falling, in some cases, like leaves, in others
being absorbed into the substance from which they sprung ;
while the ccenosarc retains its full vitality, and, in time,
will bud forth a fresh crop. When the polypite is under-
going the process of absorption, an extraordinary ferment
is visible in its digestive sac; the granules contained in
the nutrient stream are seen to be as actively at work as
when a new portion is being added to the organism,
moving restlessly about within the cavity, then hurrying
from it, and soon reentering it, until the materials of the
body have been, as it were, broken up and borne away to
be wrought into fresh structures.

Dr. Wright has observed, in the case of Hydractinia,
that in the winter the coenosarc often exists in a high
state of development, while the polypites are few in number

* " Description of New Protozoa," Edinb. N. P. Jouru. N. S. for April
1858.

XVI INTRODUCTION.

or altogether absent, and only reappear with the return of
spring. This condition may remind us the of winter rest
of the plant.

Besides the polypites, which are essential parts of
every zoophyte, special appendages of the ccenosarc are
met with in some species. Amongst these must be placed
the curious structures which have been named "nema-
tophores" by Mr. Busk, and which are characteristic of
the family PlumulariidfS . They consist of an extension of
the polypary, which may be tubular, or cup-shaped, or
conical, open at the upper extremity, and enclosing a
granular mass, in which large thread-cells are sometimes
imbedded. They may be classified as simple or compound,
sessile or pedunculate. The simple nematophore is a
chitiiious tube or cup, consisting of a single chamber. The
compound nematophore is bithalamic, having a slender
tubular portion below (Woodcut, fig. v. a) , and expanding
above into a hemispherical cup (Woodcut, fig. v. b). It is
attached at the base only, and free throughout its length ;
whereas the simple nematophore is generally to a consider-
able extent adnate to the calycle or stem.

The pedunculate form (Woodcut, fig. v.) I have only met
with on Plumularia Catharina. In this -p-

species the pair of lateral nematophores
connected with the calycle are mounted
on peduncles, by which they are raised
to about the level of the rim. They are
of the bithalamic type. The other ne-
matophores, which are profusely distri-
buted over this beautiful species, are sessile.

Good examples of the simple tubular form are afforded
by Aglaophenia phima (Woodcut, fig. vi.) and A. tubvlifera.

INTRODUCTION. XV11

Simple cup-shaped nematophores occur on Plumularia
pinnata, while those of P. sttacea and some other species
of this genus and of Antennularia are bithalamic.

The nematophores occur on various parts of the
zoophyte, and are usually present in force about the
hydrotheca. They are met with over all portions of the
stem and on the creeping fibre ; but the most remarkable
aggregation of them is found on the corbula, or case that
protects the gonophores in the genus Aglaophenia, where
every tooth on the crested ribs is formed by one of these
curious bodies*.

The contents of the nematophore have been recently
investigated by Prof. Airman f; and to him we owe the
important observation that the soft granular mass which
fills it "has the power of emitting very extensile and
mutable processes," that comport themselves in every
respect like the pseudopodia of an Amoeba, which they also
resemble in their structure. These processes " consist of
a finely granular substance, which undergoes perpetual
change of form;" and "they can be entirely withdrawn,
so as to leave no apparent trace of their existence" J.
(Woodcut, fig. vi.)

* Prof. Huxley, in a paper " On the Anatomy and Affinities of the Family
of the Medustu " (Phil. Trans. 1849, p. 427), in which, I believe, we have the
first notice of the nematophore, has described a form occurring in a foreign
species of Plumularia as consisting " of a stem proceeding from the pedicle
of the ovary, bearing a series of conical bodies.'1 This evidently corresponds
with the spur-like process fonnd at the base of the corbula in our own
Aglaophenia fubulifera, nnd is nothing more or less than a supernumerary
rib or "leaflet," edged, as all the elements of the corbula arc, with
nematophores.

t "On the Occurrence of Anicebiform Protoplasm, and the Emission <,('
!'-"ii<lopodui, among the Hydroida,'' Ann. N. H. for March 1XIV1.

\ The substance of the body amongst (he ITydroida really differs but
slightly from that, of the Protozoa. True it is differentiated into distinct

b

XV111

INTRODUCTION.

I have made similar observations on Plumularia setacea
and P. frutescens. On a young specimen of the latter
species obtained at Oban the nematophores were in a state

Fig. vi.

a

Fig. vii.

The calycle of Aglaophenia

pluma. a. The lateral
nematophore. b. The ex-
tensile process.

of great activity, sending out long filamentary processes,
which tended some upwards and some downwards, follow-
ing the course of the stem and branches, and completely
investing the zoophyte with a multitude of gossamer-like
threads. (Woodcut, fig. vii.)

It has been conjectured that the nematophores are
organs of offence. But this is hardly probable, as they
only contain thread- cells in some cases, and when present

layers ; but the ectoderm is of the simplest homogeneous texture — a struc-
tureless contractile substance, not, unlike " sarcode " in any essential parti-
cular ; and the soft masses contained in the nematophores seem to be
ectodermal offshoots, somewhat less consolidated than the layer from which
they originate.

INTRODUCTION. XIX

it would seem that these organs are not carried out in the
processes. Their number and the power which they pos-
sess of completely investing the zoophyte with their ex-
tensile threads would seem to show that they bear an im-
portant relation to the economy of the animal. They may
be concerned in the nutrition of the colony ; but without
further observations we can form no certain opinion
respecting their function*.

In the genera Hydr actinia and Podocoryne, which ap-
proach the Siphonophora in complexity of structure, some
curious appendages occur in addition to the alimentary
polypite. We have first the spiral bodies, described under
Hydr actinia echinata (p. 24), which are developed on the
edge of the common base or crust, round the mouth of
the shell that supports the colony. They are remarkable
for the energy with which they uncoil and twist themselves
about when called into action. They usually form a
somewhat dense fringe round the mouth of the shell
(which is almost always tenanted by a Hermit-Crab), and
are roused from their state of quiescence by anything that
may irritate the surface of the coenosarc. As they are
well armed with thread-cells they may be regarded as
organs of offence, though it is difficult to understand how
they can act very effectively against the enemies of the
commonwealth.

The other appendages referred to are long and extensile
filaments that spring from the surface of the cosnosarc
in certain portions of the colony, like the tentacles of
Velella, and which Dr. Wright regards as fishing-lines,

* In the account of Hydr actinia echinata (p. 25) I have treated the ne-
matophorcs as offensive organs ; but since this passage was written I have
conic (o the cmiclusion that this is probably not their function.

h 2

XX INTRODUCTION.

enabling the zoophyte to seize food scattered about on tin-
ground by the Crab when feeding*.

Perhaps the most extraordinary of the crenosarcal ap-
pendages met with amongst the Hydroida are the snake-
like organs with which the genus Ojthiodes is furnished.
(Plate XLV. fig. 2 a.) One of them is always stationed
close to the polypite, and great numbers are distributed
upon the creeping stolon. They are vigorous in their
movements, capable of enormous elongation, and sur-
mounted by a large capitulum, thickly covered with
thread- cells. They may act not only as organs of defence,
but also as auxiliaries in the capture of food.

The Hydroid colony is enlarged by a purely vegetative
process : fresh polypites bud rapidly from the prolific pulp ;
and in the larger and arborescent kinds branches and
branchlets germinate, according to the pattern of the
species, from the zoophyte as from the tree. For the
multiplication and diffusion of the species, special zooids
are set apart; and to them is allotted the reproductive
function, as to the polypite that of nutrition. They cor-
respond with the flower-buds of the plant.

REPRODUCTION.

The polypites, or feeders, of the Hydroid colony are
almost always present ; the sexual zooids are developed at
certain seasons only, in buds of peculiar structure, which
occupy different positions in different species. Amongst

* Allman regards these filaments " as an abnormal state of the ordinary
polypite," and stales that they are not usually present. But on examination
Iliey are found to bear the cln.-rM resemblance to a tentacle, bring slightly
enlarged towards the tip, and endowed with extraordinary extensibility.
They oeeiir both on Hydractinia and Podocoryne cnrnca, and, I believe, are
very generally present, though when contracted they are with difficulty
recogni/.i ''

INTRODUCTION. \ \ I

the Thecaphora, these reproductive buds are always borne
on an offshoot from the ccenosarc, which is enclosed in a
chitinous receptacle or urn (gonothcca) . (Woodcut, fig.
xv.) In the suborder Athecata they are never protected
by a true gonothcca,, though in sonic species they are
encased in a thin coating of chitiue. In this division they
occupy very various positions. Sometimes they are deve-
loped irregularly amongst the tentacles of the ordinary
polypite (Coryne), or at different points on the body (Cla-
vatella and Podocoryne) ; in other cases they occur on
the cosnosarc (Periyonimus) , while in Tubularia and its
allies they germinate at the base of the lower circle of
tentacles. In other cases, again, they are borne on special
zooids, which are evidently polypites more or less atro-
phied and deprived of some of their characteristic parts.
The atrophy varies in degree : sometimes it shows itself
in a reduction of the number of tentacles ; sometimes these
organs are represented by mere clusters of thread-cells
(Hydr actinia); sometimes they are altogether wanting
(Cionistes], and the polypites become nothing more than
a columnar offshoot from the coenosarc, closely resembling
that which bears the gonophores within the capsule of the
Thecaphora. The zooid (whether modified or not) which
carries the reproductive buds may be designated the fertile
or proliferous polypite *.

In Hydra the reproductive buds are developed within
definite regions on the body of the polypite, and are gene-
rally produced when the ordinary gemmation has altogether
ceased, or is beginning to fail, (Woodcut, fig. 40, p. 313).

The gouophores exhibit many modifications; like the

* The modified polypites whose function it is to originate the sexual buds,
and which take no part in the nutrition of the colony, are the c/onoblast'uliu
of Huxley.

XX11

INTRODUCTION.

flower-bud of the plant, they have their many forms and
even colours. If we examine their structure we find that
the apparent differences amongst them are numerous and
striking ; but a closer investigation shows us that, amidst
all the deviations, a community of plan may be traced.

The sexual bud consists (almost universally) of an outer
investment (the ectotheca), which serves as a protective
case, and a contained zooid, which may be male or
female, and which originates sooner or later the gene-
rative elements. The two sexes are sometimes borne on
the same colony, but more commonly the zoophyte is
dioecious. The cases, however, are much less rare than
had been supposed, in which both the male and female are
mingled on the same shoots. The Hydra is sometimes
monoecious and sometimes dioecious, the true representative
of its Order in this as in so many other points.

The sexual zooids are either fixed or free. They either
continue attached and mature and discharge their con-
tents in situ (Woodcuts, figs. viii. and ix. ), or at a certain

Fig. viii.

Fig. ix.

VIII. The gonopliore of Clava. — a. The spadix, communicating with the
ccenosarc. b. The endoderm of the gonozooid. c. The ectoderm of the same.
(I d. The ectotheca, enclosing the gonozooid. a'. Ovum. The gonozooid.
n, b, c, is the equivalent of the manubrium. IX. Gonophore of Aglaophcnia

INTRODUCTION.

XX111

stage of their development they liberate themselves from
the parent stock, escape from the sac which had hitherto con-
fined them, and enter on a term of independent existence.
(Woodcut, fig. x.)

Fig. x.

a.

a. The gouozooid enclosed in its ectotheca. b. The same, after the rupture
of the sac, on the point of detaching itself.

They are now altogether separated from the colony to
which they belong, and so thoroughly are their affinities
concealed by the locomotive and other adaptive organs
with which they are furnished, that they might readily
pass for members of another tribe. Indeed we can
scarcely imagine a more complete contrast to the staid and
stationary zoophyte, in outward form and habit of life, than
tlic medusiform zooid which it evolves from its own sub-

XXIV

INTRODUCTION.

stance and sends forth laden with the seed of new com-
monwealths.

The free sexual zooid, with two or three exceptions,
assumes the form of a medusa, and is furnished with a
contractile swimming-bell or umbrella, by whose rhyth-
mical contractions it is propelled through the water.
(Woodcut, fig. xi. a.)

From the centre of the crystal dome is suspended a hollow

Fig. xi.

body (the manubrium, Woodcut, fig. xi. 6), terminating at
the free extremity in a mouth, and at the point of attach-
ment in communication with a number of radiating tubes
or canals (Woodcut, fig. xi. c), which pervade the substance
of the umbrella, extending to its margin, where they join
a circular canal that connects them all (Woodcut,

INTRODUCTION.

XXV

fig. xi./, /). The swimming-bell (the float and natatory
organ, and the most striking feature of the structure) is
partially closed below by a filmy membrane or veil, in the
centre of which there is a circular aperture (Woodcut,
fig. xi. e). Its margin is furnished with a larger or smaller
number of tentacles, and in many cases with a series of
small sacs, in which one or more refractile spherules are
enclosed. The latter are in all probability simple organs
of sense ; but of what nature, we are not in a position to
determine (Woodcut, fig. xii.) . Their function has been

Fig. xii.

,(. The t-ireular c.uml. />. The ocellus, c. The sac or litlioi-jsi. c'. The
spherule of lime.

XXVI INTRODUCTION.

supposed to be auditory ; but the conjecture is hardly
borne out by an extended investigation of their structure.

At the base of the tentacles (Woodcut, fig. xii. £) there
is often a collection of pigment-cells (a coloured spot or
ocellus) in which a crystalline body is sometimes imbedded,
as in Eleutheria and Clavatella. In Tiaropsis diademata,
Agassiz describes as many as fourteen highly refractive
bodies, or lenses, as forming a crescent within the pigment-
spot*. These ocelli are regarded, with much probability,
as rudimentary organs of vision, or at least as holding a
place in the Hydroid economy analogous to that of the
eye in higher organisms. It is interesting to remark that
these very simple organs of sense make their appearance
only in the zooids which are destined to become free.

The digestive cavity is lodged in the rnanubrium, and
the nutritive material prepared in it passes into the canals
and circulates through them ; the oral extremity is some-
times lobed, and sometimes furnished with tentacular
appendages, which assist in the capture of food.

The generative elements are developed either between
the two membranes that form the walls of the manubrium,
or in special sacs, which are borne on the radiating canals
(Woodcut, fig. xi. o). They usually occur in the former
position amongst the Athecata, and in the latter amongst
the Thecaphora ; but the distinction is not universal. The
period at which the ovaries and spermaries make their
appearance varies considerably; in some cases they are
developed before the zooid detaches itself, in others not
until long after its liberation.

The free gonozooid has by no means attained its full

* Contributions to the N. II. of the U. S. vol. iv. p. 300.

INTRODUCTION. XXV11

development and perfect form on leaving the parent stock;
in a large proportion of cases it undergoes very con-
siderable change subsequently. The form of the umbrella
may alter, and the marginal tentacles and other bodies
and even the radiating canals increase greatly in number ;
while the manubrium may become much elongated, or
develope additional oral appendages *. The early and
mature states are often so dissimilar as to have been re-
ferred to different species ; and as there is seldom the
opportunity of observing the whole course of development,
the varying phases of the sexual zooid are a source of
much perplexity to the systematist f.

Gemmation is not confined to the fixed portions of the
Hydroid colony ; it also enters into the history of the free
and locomotive zooids. In many cases they manifest the
vegetative tendencies of their tribe, and multiply rapidly
by budding. Gemmation seems usually to take place
when the true reproductive function is in abeyance. Thus
in the spring the gonozooid of Clavatella developes buds
on the margin of the body between each pair of tentacles,
which are cast off at a certain stage of growth ; while
later on in the year the vegetative activity ceases, and
reproduction by ova and spermatozoa takes its place.
These buds, which are analogous to those produced in
such profusion by the Hydra, bear an exact resemblance,
when mature, to the zooid that originated them. In other
cases they spring from the manubrium, or from the bul-

* A. Agassiz has pointed out that the tentacles are developed in a certain
fixed order, and has given the formula of development for many species.
(Proc. Boston Nat. Hist. Soc. vol. is., August 1862.)

t A good illustration of the changes which the detached zooid may undergo
before reaching maturity, and of the complexity of structure which it may
finally attain, is afforded by the genera Bouff(dut'i[li« and 7,</yt>ducf>/[a.

XXV111 INTRODUCTION.

bous base of the tentacles, or from the tentacle itself, or
from the radiating canals.

The free zooid, then, after its detachment, may pass
through many stages of growth and development itself,
and originate a large number of similar organisms, before
proceeding to discharge its principal function, the elabo-
ration of the generative elements. With the escape and
dispersion of the latter, its existence, in all probability,
usually terminates.

Towards the end of its course it sometimes loses its loco-
motive organs and passes into a state of quiescence, and in
this condition closely resembles, in all essential particulars,
an ordinary polypite. The locomotive energy fails, the
umbrella is first reversed and then shrinks into a shapeless
mass, which hangs about the base of the body, and bears
the tentacles streaming behind it. (Woodcut, fig. xiii.)

Fig. xiii.

The medusiforin zooicl of Podocoryne carnca in its quiescent stage. — a. Tlic
remains of the swimming-bell, b. The tentacular bulbs, o. The ova in the
walls of the manubriuui.

The adaptive dress which had fitted the zooid for a free

INTRODUCTION. XXIX

existence, and which disguised its real affinities, is cast
aside, and that which remains is at once recognized as a
polypite. During the period of quiescence the ova are
liberated, and the mamibrmm then dissolves away *.

It would be difficult to exaggerate in speaking of the
beauty of these floating flower- buds, as they may well be
called. The vivid tints which they often display, the
gracefulness of their form, the exquisite delicacy of their
tissues, and the vivacity of their movements, combine to
render them singularly attractive. Frequently they are
so perfectly translucent that their bubble-like forms only
become visible in a strong light. In other cases the um-
brella is delicately tinted, while the manubrium displays
the gayest colouring, and brilliant ocelli glitter on the
bulbous bases of the tentacles. To their other charms that
of phosphorescence is often added; they are not only
painted like the flower, but at night they are jewelled with
vivid points of light, set round the margin of the bell, or
one central lamp illumines the little crystal globe, and
marks out its course through the water. Though indi-
vidually minute, their numbers are so immense that they
play an important part in the production of the luminosity
of the ocean. The surface of the sea for miles together
is often thickly covered with them ; and on still, sunny days

* This " retrograde metamorphosis " has been observed by Dujardin and
Holdsworth in Cladoncma — in Podocoryne by Loven, Peach, and myself, in
Byncoryne by Allman and myself, and in Turris by Gosse, who remarks,
after describing the reversion and disappearance of the umbrella, "of the
scores kept, this was the common, and therefore, I suppose, the natural ter-
mination." I have observed the same thing universally in Podocoryne carnea.
The gonozooid of Clavatella, which has no swimming-bell to dispose of,
equally loses its locomotive habit towards the close of its life, and fixing itself
by the suctorial disks that had before served it as feet, remains perfectly
inactive until the escape of the ova, which is speedily followed by its own
dissolution.

XXX INTRODUCTION.

iii autumn certain species swarm in immense shoals off
the coast *. Any one who has watched the escape of the
goiiozooids from a specimen of the common Obelia genicu-
luta will feel no surprise at the accounts which are given
of the numbers of minute medusas that sport near the
surface of the ocean, and at night make it glow with
phosphoric fires.

In this species each of the pretty urn-like capsules,
which are produced in great profusion, contains a large
number of zooids ; and several hundreds are soon liberated
even from a small specimen. On the vast tangle-beds that
fringe all portions of our coast, Obelia geniculata is uni-
versally present, forming extensive forests over the long
ribbon-like fronds ; and from these, during the breeding-
season, countless thousands must be cast off.

The stationary life of the polypi te does not offer much
to interest the observer ; but the habits of the medusiform
zooids are singularly attractive.

Like miniature balloons they float suspended in the
water for awhile ; then they suddenly start into motion,
propelling themselves by a series of vigorous jerks or casts,
and at the same time contracting the tentacles into the
smallest compass ; then they become quiescent again, and
sink slowly and gracefully, like parachutes, to the bottom
of the vessel, some of the arms extended laterally, and the
rest dependent. In all cases locomotion is effected by the
pulsation (the alternate systole and diastole) of the swim-
ming-bell.

The tentacles have various uses. They assist in the
capture of prey ; they are employed as organs of attach-

* A. Ayassiz. ' Catalogue of North American Acalepba1,' p. 7-'!.

INTRODUCTION. XXXI

ment, by means of which, the zooid anchors itself while
searching for food ; they also serve occasionally as legs.
They are well armed with thread-cells, the deadly power of
which compensates for the feebleness of the frail organism
in other respects, and enables it to deal with creatures
much higher in the scale of being than itself.

It is interesting to watch the zooid when in quest of
food. Anchoring itself by some of its tentacles, it casts
out the remainder in all directions, elongating and attenu-
ating them to an extraordinary degree, and keeping the
extremities in a state of incessant tremulous motion, as if
feeling for something.

The mouth, placed as it is at the extremity of a free and
extensile body, and often furnished with tentacular appen-
dages, is in itself well adapted for the capture of prey. In
the later stages of its existence, when the swimming-bell
has collapsed and the tentacles are no longer available, the
gonozooid is dependent on this organ for its supplies of
food.

At first sight there appears to be a total dissimi-
larity between the (so-called) medusa and the polypite.
In general aspect and in mode of life they present a
striking contrast. The structural affinities between them
are completely veiled by the modifications which adapt the
sexual zooid to a free and locomotive existence. The swim-
ming-bell is a mask, behind which the polypite is effectually
concealed. We cannot wonder that the escape of the
(so-called) medusa from the reproductive capsule of the
zoophyte was at first regarded as a marvel, and excited so
lively an interest. But the medusiform structure (which,
with one or two exceptions, is characteristic of the zooids
that are destined for independent existence) is only a

XXX11 INTRODUCTION.

variation on that which we find in the polypite, exhibiting
the same principal elements, which are modified in con-
formity with the new conditions of being. The free gono-
zooid is essentially a polypite suspended in a contractile
bell, which bears it through the water. We have only to
imagine an ordinary alimentary zooid, detached and with
its tentacles united by a web for a portion of their length,
to have a structure closely resembling the (so-called)
medusa. In Campanulina acuminata the arms of the poly-
pite are, to some extent, palmate (Plate XXXVII. fig. b],
and in the delicate web which connects them we have the
homologue of the swimming-bell*. A polypite of this
genus, separated from its colony, and floating by means of
its tentacular disk, would suggest at once the aspect and
habit of the medusiform zooid.

In its highest form the sexual polypite takes on a struc-
ture which fits it for independent existence. The tubular
appendages, which in the nutritive zooid are mere prehen-
sile organs f, are now connected for the greater portion of
their length by a highly contractile membrane, and form
a bell or disk, which serves as a float and a propeller. The
extremities remain free, and discharge the office of ten-

* Prof. Allman has remarked that in all cases the tentacles of the poly-
pite are necessarily included in the thickness of the body-walls for some dis-
tance from their origin. And this included portion he regards as the repre-
sentative of the radiating canals. (" Report on the Reproductive System in
the Hydroida," Rep. Brit. Assoc. for 1863, p. 364.)

f The view which regards the tentacles of the polypite and the radiating
canals of the (so-called) medusa as homologous parts is confirmed by many
considerations. It is worthy of remark that in some cases (e. g. Zygodacfyla)
the canals increase in number as the zooid advances towards maturity, just
as the tentacles of the polypite do ; and the course of development is the
same in both. The new canals originate at (lie base of the manubrium, and
irradually grow downwards to the circular vessel on the margin.

INTRODUCTION. XXX111

tacles. An outgrowth from the margin of the membra-
nous bell forms the veil, which partially closes it below.

The body, containing the stomach, and corresponding
with the proboscis or anterior portion of the ordinary
polypite, is suspended, as it were, from the centre of the
domed roof of the swimming-bell, and hangs free in its
cavity. In the alimentary polypite the homologous struc-
ture stands erect in the centre of the tentacular wreath.

The tentacular tubes, which form in the free zooid the ribs
on which the umbrella is, as it were, supported, also serve
as the canals through which the nutritive fluid circulates*.
They communicate, like the tentacles of the polypite, with
the cavity of the stomach, and are further united at the
margin of the swimming-bell by a circular canal. This ad-
ditional structure completes the simple circulatory system.
So far it is the only element which has not its homologue
or equivalent in the polypite.

In Clavatella we have an intermediate form, which
throws much light on the relation of the medusiform
structure to that of the polypite, and very clearly links the
two together. In this genus the sexual zooid, though free
and locomotive, is not furnished with a swimming-bell.
It wants the striking feature of the (so-called) medusan
structure, and, instead of floating and swimming, moves by
means of suctorial disks, borne at the extremity of a branch
or fork of the arms. (Plate XII. fig. 2 a.) But though
ambulatory in its habits and destitute of the contractile
float, it reminds us at once of the medusa. It has the
same general form : as it moves, the mouth hangs down-
wards ; and round the body, at the base of the tentacles,

* In the Hydra, the tentacles are simple tubes into which the fluids pene-
trate freelv.

XXXIV INTRODUCTION.

are a number of coloured ocelli. On examination it is
found to be furnished with radiating canals, which are
short and broad, and correspond in position with the arms.
There is also a circular canal.

The tentacles exactly resemble those of the polypite,
with the exception of the branches bearing the adhesive
disks. In other respects there is the closest resemblance
between the free zooids of Clavatella and its polypite.
The oral extremity of the latter, detached from the long
pedunculated body which supports it *, requires very slight
modification to convert it into the curious ambulatory
structure which is charged with the propagation of the
species. Putting aside for the moment the eye-specks and
the locomotive appendages which are superadded to the
stationary organism, there is but a single point of diffe-
rence between the two of any significance. In the gono-
zooid a larger portion of the tentacles is included in the
body-walls than in the polypite, and the included portions
are united by a circular vessel f. The sexual zooid of
Clavatclla may be regarded as a partially developed me-
dusa ; it is as clearly a slightly modified polypite. If we
imagine the extension of the body- wall upon the tentacles
to be carried somewhat further, we have the perfect
swimming-bell.

The close resemblance between the gonozooid and the

* This seems to have its homologue in the pedicle by which the gonozooid
is attached to the parent stock, a portion of which it bears with it for a time
after liberation,

It may be noted further that the reproductive buds of Chivatdla are de-
stitute of any ectothecal covering, and exactly resemble the polypites in their
mode of growth.

t The study of Cluvah'Ua leaves no room for doubt as to the homological
relation between the mdiating canal and the tentacle

INTRODUCTION. XXXV

polypite in this zoophyte is somewhat concealed by the
peculiar habit of the former, as it is seen striding along
with inverted mouth. But in the kindred genus Eleutheria
the special locomotive organ is wanting, the mouth of the
gonozooid is turned upward as it moves, and it has all the
appearance of a polypite propelling itself, with little appa-
rent ease or agility, by means of its tentacles.

So much may suffice respecting the structural identity
between the two principal elements of the Hydroid colony
— the polypite and the (so-called) medusa, which, on a
superficial view, appear to offer such a complete and
striking contrast *.

In the free sexual zooid with its contractile bell and
mercurial habit, which not only matures but also diffuses
the seed of new generations, the hydroid structure reaches,
as it were, its culminating point.

In a large proportion of cases, however, the reproductive
element appears in much humbler guise. The gonozooid
is permanently attached to the colony, like the alimentary
polypite, and developes and liberates its products in situ.
Amongst these fixed zooids, which are extremely numerous,
a gradation of structure is traceable. A series of transi-
tional forms connects the simplest of them, which is a
mere sac, with the most complex, which makes a near
approach to the medusa in structure, though not destined
to become free. In different species the development of
the gonozooid is, as it were, arrested at different points ;
and it is only in certain cases that it attains the highest

* I have not attempted to give an exhaustive view of this deeply interesting
portion of my subject. Those who desire a fuller treatment of it may con-
sult the works of Prof. Allman, and especially his admirable paper on C'or-
di/lophora (Phil. Trans. June 1853), and his " Eeport on the reproductive
system in the Hydroida." Report Brit, Assoc. for 18<>3, pp. 3

c2

XXXVI

INTRODUCTION.

condition — that of an organism endowed with the means of
locomotion, and fitted for independent being. Thus in
Hydra it is a mere bulging of the body-wall, between the
two layers of which the generative elements originate ; and
this, it must be remembered, is the earliest stage of all the
more complex forms. In Clava it is a distinct process,

Fia\ xiv.

V-

I

i ,

-

Male capsule of Gonothyr&a Loveni. — a. A gonozooid, still within the
capsule, b. The spermatic mass. c. The spadix communicating with the
cavity of the ccenosarc. «'. A gonozooid, borne at the summit of the capsule,
discharging the spermatozoa, b'. The spermatic mass, fully developed, c'.
The spadix.

containing a prolongation of the general cavity of the body,

INTRODUCTION. XXXVU

enclosed by the two membranes (ectoderm and endoderm) ;
it is, in fact, a manubrmm without the oral aperture, nutri-
tion being provided for by the general circulation. In other
cases a membranous envelope (which is the equivalent of the
swimming-bell) and rudimentary radiating canals are super-
added. In Tubularia a still further advance is made ; the
gonozooid, though permanently attached, is furnished with
a swimming-bell, in which the canals are present and the
orifice, round which are set four tubercles representing the
marginal tentacles. (Plate XX. fig. b.} The manubrium
is destitute of a mouth. In this form there is every prepa-
ration for free existence up to a certain point; but the gono-
zooid remains enveloped in the ectotheca, and the swim-
ming-bell is converted into a nursery, in which the embryo
passes through the later stages of its development. In Gono-
thyraa (Woodcut, fig. xiv.) a yet nearer approach is made to
the medusiform structure : the umbrella is furnished with
tentacular appendages ; and the gonozooid at a certain stage
is pushed beyond the orifice of the capsule, and hangs
there as if on the very point of escaping and entering upon
a separate existence. It maintains its connexion however,
and, like the seed-vessel, after ripening and scattering its
products it withers away.

Many other modifications occur ; but those which have
been mentioned exhibit the gradual transition from the
simplest to the most complex form.

Occasionally we see the development of the gonozooid
arrested at a certain stage, and, instead of becoming free as
in normal cases, it continues in connexion with the parent
stock. Thus in Syncoryne the sexual zooid is usually
locomotive ; but towards the close of the breeding, season, it
is sometimes met with in a depauperated condition, without

XXXV111

INTRODUCTION.

tentacles and with a merely rudimentary mouth : though
the swimming-bell exhibits contractility, it never acts as a
locomotive organ, but the zooid continues attached and
does not attain a much higher point of development than
that of Tubularia. I have observed a similar seasonal
arrest of development in Podocoryne proboscidea. In such

Fig. xv.

' , " /

Female capsule of Campanularia flexuosa. — a. An ovum, with germinal
vesicle and spot, still confined between the walls of the gonophore. b. The
spadix, communicating with the general cavity of the cceuosarc. c. An ovum
in one of the stages of segmentation, d. A planula. r. The ccenosarc of the
zoophyte.

INTRODUCTION.

XXX IX

cases we have the fixed and the free condition of the gono-
zooid within the limits of a species, the former being
abnormal and the result of partial development, but
representing a perfect and permanent form in another
portion of the series.

It only remains to give a short account of the develop-
ment of the Hydroid embryo. (Woodcut, fig. xvi.) The

Fig. xvi.

a-

1. The planula of a Carupanularian Hydroid.

2. The same, in a more advanced stage. — a. The enlarged extremity, by
which the embryo attaches itself, b. The chitinous film. c. The point at
which the polypite is developed.

3. The young Campanularian soon after attachment. — a. One of the tubular
lobes into which the disk divides.

The arrows show the direction in which the planulc moves.

ovum after impregnation passes through the various stages
of segmentation, and is resolved at last into a minutely

xl INTRODUCTION.

granular mass; and this, by the rearrangement of its
material, and further development, is transformed into the
elongate and somewhat conical embryo known as the
planula. (Woodcut, fig. xvi. 1.) When mature, the em-
bryo escapes from the reproductive sac into the water, and
for a short period enjoys a free and active existence. The
centre of the body is now found to be occupied by an
elongate cavity ; the walls which enclose it are composed
of two layers, the ectoderm and eudoderm ; and the surface
is all but universally clothed with vibratile cilia*. After
a while the body enlarges towards one extremity, and a
thin chitinous film forms over a portion of its surface
(woodcut, fig. xvi. 2); the movements become sluggish ; and
at length the cilia disappear altogether, and the embryo
fixes itself by the enlarged end, which expands into a flat,
circular disk, the remainder of the body standing erect in
the centre of it. (Woodcut, fig. xvi. 3.) The disk, by which
the embryo is now permanently attached, soon breaks up
into a number of lobes, which again divide dichotomously.
(Woodcut, fig. xvi. 3 a.) The whole structure is at this
stage invested by a chitiuous envelope or polypary.

As development proceeds the upper extremity is moulded
into a polypite within a transparent urn, the lid of which
it pushes off when mature. From this primary stem, with
its single polypite, by a series of successive buddings the
complex plant-like structure is evolved ; while the discoid
base gives off the delicate threads that net the surface of
weed or stone, and originate and hold together in organic
union whole forests of tree-like shoots.

* The planule of Coppinia arcta, in many respects an anomalous species,
is not ciliated. The embryos of Coryne vaginata are unciliated amoeboid
bodies, which undergo remarkable changes of form after liberation.

INTRODUCTION.

Xli

The course of development is subject to one or two
variations. In some cases the entire body of the embryo
on becoming attached spreads out into a circular disk, from
the centre of which the stem is subsequently developed.
In Tubularia (Plate XX. figs, c, d) and in Coryne Van-Benc-
denii (p. 46) the planule stage is wanting, and the embryo
takes on the form of the polypite before leaving the gono-
phore. When it escapes from its confinement the body is
furnished with an oral aperture at one end, surrounded by
a number of tentacles ; it continues locomotive for a short
time, and then fixes itself by the aboral extremity, and
developes a stem and the full complement of arms.

In some of the species which are furnished with a

Fis. xvii.

d

The gonotlieca of Sertularia cupressina. — «, b, c. The capsule crowned by
the marsupium in various stages of development, d. The capsule with the
marsupium ruptured for the escape of the planulse.

chitinous receptacle for the protection of the gonophores
(Thecaphora] , the ova at a certain stage are transferred to
a kind of nest or marsupial sac enveloped in a thick

xlii INTRODUCTION.

gelatinous covering*, and borne at the summit of the
capsule, in which they complete their development.
(Woodcut, fig. xvii.) This species of nidification is far from
uncommon. The marsupium is sometimes formed, as
Allman has suggested, by an extension of the endotheca
or membrane which immediately confines the ova (Wood-
cut, fig. xvii.) ; but in other cases the entire gonozooid is
pushed upward, and at last beyond the opening of the
capsule, by the growth of the column supporting it, and,
having secreted a gelatinous coating, is converted into a
kind of nest, in which the ova pass through the later stages
of their development f.

It may be well briefly to sum up the leading facts of the
reproductive history of the Hydroida.

In each colony, the alimentary and reproductive func-
tions are distributed amongst two classes of zooids.

The sexual zooids, like the flower-bud of the plant, are
only developed at certain seasons, and occupy various
positions in the different species. In a large number
of cases they exhibit a modification of structure adapt-
ing them for independent existence, and when mature
detach themselves from the colony and become free and
locomotive.

The free sexual zooid, in all but one or two exceptional
cases, may be regarded as essentially a polypite with its
arms united by a contractile web, so as to form a float and
natatory organ. Disguised by its adaptive dress, it has
been separated from its kindred under the name of a
medusa; it is in reality a swimming polypite.

* The acrocyst of Allman.

I' Wright has observed this in Opercularella /nc/ruttr. The marsupium of
Campamdaria neglectu is formed in the same way. ( Vule p. 172.)

INTRODUCTION. xliii

When liberated, it matures and disperses the generative
elements, and, having thus fulfilled its function, perishes.

In other cases the gonozooids never become free, but,
like the alimentary polypites, remain in permanent con-
nexion with the colony. In this condition they exhibit
many diversities, and constitute a series of transition forms
leading up to the highest, in which the provision for a free
and locomotive existence is complete.

The embryo of the Hydroida is all but universally a
ciliated body, the analogue of the winged seed of the
plant, which diffuses the species.

RATE OF GROWTH. PHOSPHORESCENCE.

All the evidence we possess on the point seems to show

that the development of the fixed Hydroida proceeds

rapidly. Timber immersed in the sea is soon found to be

covered with a luxuriant growth of zoophyte. Mr. Couch

considers it probable that a large specimen of Sertularella

polyzonias may be formed, under favourable circumstances,

in fourteen days. At Rio Janeiro a Eudendrium, allied to

E. rameum, has been observed to cover the bottom of a

boat in fifteen days. Stimpson mentions that, on the

hooker which he used for dredging at Grand Manaii,

an Obelia had reached the height of an inch in less than a

month after the bottom of the vessel had been scraped

clean ; and Van Beneden speaks of the great rapidity with

which Tubularia coronata is developed along the coast of

Belgium*.

* The following illustration of the enormous rate at which some of the
Hydroids multiply is from M'Cracly: — "I have observed the medusas (of
Tubularia cristata) fully grown and casting their larva; as early as March 10th,
and as late as September 13th, during all which time thousands of larv;u arc

xliv

INTRODUCTION.

As amongst plants, some species are annuals, especially
such as are parasitic on the fronds and stems of seaweed,
while others are probably perennial. The large, arbores-
cent masses of the stouter kinds of Sertularia, Halecium,
Eudendrium, &c. must be the growth of several seasons.
Van Beneden has seen specimens of Tubularia and Cam-
panularia live for several years in an aquarium without
any diminution of their vegetative activity. The medusi-
form zooids, the vagrant members of the colony, are com-
paratively shortlived ; their function is seasonal, and as
soon as it is fulfilled they perish*.

It seems to be not improbable that the polypites in
some cases perish in the winter, like the leaves of decidu-
ous plants, and are renewed with the return of spring.
Lamouroux states that he had found this to be the case in
some species; and Lieut. Thomas, in a note on Euden-
drium ramosum, records the fact that at Alloa, where this
zoophyte is abundant, no specimens were found "with
' heads ' on in the month of November " f. Dr. Strethill
Wright, too, as mentioned before, has seen many speci-
mens of Hydr actinia in which the coenosarc was fully
developed in winter, but the polypites were few in number

continually shed, and in consequence thousands of new colonies established,
their multiplication becoming so great during a favourable season that the
rocks literally appear clothed with the yellow stems and rose-coloured blos-
som-like bodies of these flower-animals."— G-ymnophthalmata of Charleston
Harbour, Proc. Elliott Soc. Charleston, vol. i.

* "Dans les plantes comme dans les auimaux, la vie est generalernent
longue et la tenacite grande dans les individus agames ; ephemere et delicate,
an contraire, dans les individus sexues. L'analogie entre la mednse et la
fleur so confirme de plus en plus." — Fan Ben. Polypes, p. 101.

t Supplement to Johnston's ' British Zoophytes,' p. 467.

INTRODUCTION.

or altogether wanting. On the return of spring, however,
they reappeared.

The polypites of the Hydroid colony, as well as their
raedusiforra brethren, exhibit in many cases the beautiful
phenomenon of phosphorescence. This has been observed
in many species, but only, I believe, amongst the Theca-
phora. Mr. Hassall has celebrated the beauty of the trawl-
nets when raised at night, draperied with zoophytes which
glitter " like myriads of the brightest diamonds." The
luminosity resides in the living polypites, which, when irri-
tated, instantaneously light up their little coloured lamps,
and literally flash fire at their assailants. The common
Obelia geniculata, which may be met with on every coast, is
a phosphorescent species, and, if agitated soon after its
removal from the sea, will furnish a fine display of " living
stars."

GEOGRAPHICAL DISTRIBUTION.

Little can be said on this branch of the subject. So far
as we can judge, the British Hydroida, with a few excep-
tions, are generally distributed round our coasts. There
seems to be little localization of species. As yet we have
only an imperfect knowledge of the distribution of the
smaller kinds ; but the large and well-known species have
most of them a very wide range. A few forms are essen-
tially boreal and do not descend below the north-eastern
section of the English coast : such are Salacia abietina
and Sertularella tricuspidata. Sertularia fuse a has only
been observed on the east coast of Scotland and the north-
east coast of England.

The eastern sea-board is fully exposed to the sweep of
polar currents, which exert a very marked influence on its

xlvi INTRODUCTION.

fauna. This is recognized in the absence of many fine
species of Hydroida which occur on the southern and
western coasts, as well as in the presence of a few northern
forms that are not found elsewhere, and the prevalence of
others which become rare in warmer districts. Thuiaria
thuja, which is abundant in the extreme north (North Cape
Sec.), is one of the characteristic hydroids of the east coast
of England. It all but disappears in the west, being ex-
tremely rare along the coasts of Devon and Cornwall. The
Aglaophenice, 011 the other hand, which flourish so re-
markably in the south-west and along the north-western
coasts that are exposed to Gulf-stream influences, barely
put in an appearance in the north-east.

Of A. pluma Mr. Alder mentions only a single specimen
as having occurred in Northumberland and Durham. A.
myriophyllum is reported equally rare, while A. pennatula
and A. tubulifera are absent altogether.

Three species, Diphasia alata, Calycella fastigiata, and
Afflaophenia tubulifera, have been found in Cornwall and
also in Shetland, the Hebrides, and on the west coast of
Scotland, but nowhere else in Britain. The last-named
flourishes luxuriantly in Oban Bay, having for its com-
panion there, as in Cornwall, the beautiful coral, Caryo-
phylla Smithii; and it has lately been obtained by Mr.
Norman in the Hebrides. There can be little doubt that
the peculiar distribution of these species, no less than that
of the Madrepore, is due to the influence of the warm
current, which after bathing the south-western shores of
England, sweeps away to the north, touching the Orkneys
and Shetland in its course. Afflaophenia tubulifera is also
a South-African form.

To the same genial influence we owe the remarkable

INTRODUCTION. xlvii

beauty and luxuriance that distinguish the zoophytes of
Devon and Cornwall and, to a less extent, of the west coast
of Scotland.

A few species are decidedly local. Diphasia pinnata, the
finest of the British Scrtulariidse, is confined to the coast
of Devon and Cornwall. Coryne vaginata is the common
representative of its family in the south and west, but
does not range northward, so far as we know at present.

Syncoryne eooimia fills a similar position on the east
coast, and does not appear to occur elsewhere.

A large number of the Athecata have only been observed
hitherto in the north ; but as most of them are minute
species, and have only been discovered recently, we should
not be justified in drawing any inferences as to the extent
of their range.

If we turn now to the foreign relations of the British
Hydroids, we find that a large number of them occur along
the Atlantic coasts of North America, mingled with others.
At least thirty species are known to be common to the two
faunas*. The North-Pacific forms seem to be altogether
distinct from our own. A few of our British species cluster
about the North Cape : most of these have a very wide
range of distribution ; but one or two are chiefly confined
to the north-eastern division of our coast.

Many Hydroids are common to Britain and the Medi-
terranean. Clavatella, which has been found as far north
as Whitby, on the east coast of England, ranges to Nice ;
and Podocoryne carnea is at home in Norway and at
Naples. Some of our species are inhabitants of the coast
of Labrador, the polar waters that bathe the North Cape,

* The Hydroid fauna of Labrador and the Gulf of St. Lawrence seems to
be to a large extent identical with that of our own north-eastern coasts.

xlvili INTRODUCTION.

and the Mediterranean. A small group of forms, including
a few of the Plumulariidee and some of the most cosmo-
politan of the Sertulariida, is common to Britain and
South Africa.

In the South Pacific the Hydroid genera are represented,
for the most part, by species distinct from our own ; but a
few British forms have been noticed at various points in
Australia and the neighbouring seas*.

METHOD OF COLLECTING THE HYDROIDA.
The British Hydroida are all marine, with the exception
of Hydra (a truly fluviatile form) and Cordylophom (which
is an inhabitant of fresh water here, but elseAvhere is met
with in waters more or less saline) . Some of the species
are confined to deep water; but a very large proportion
are littoral, or inhabit the Laminarian zone, which skirts
the shore. On a favourable coast, where a large extent of
rock is laid bare at low tide, a rich harvest may be gathered
without resorting to the use of the dredge. A large num-
ber of the more minute Athecata (Hydr actinia, Corynidce,
Atractylida, Tubulariidae, &c.), including many of the
rarer and more interesting forms, are littoral in their
habits, and also many of the Campanulariidae (the exquisite
' ' Bell Corallines "), of the smaller Plumulariidae, and other
Thecaphora. Many species manifest a preference for cer-
tain zones of the space included between tide-marks, and
are only found within very definite limits. Some are
confined to certain kinds of weed, or almost invariably

* Diphasia pinnata at Sydney (and also in South Africa), PlmntiJaria
obliqua in Van Diernen's Land, Sertularia attenuata at Port Adelaide, and
Lafoea fruticosa in Bass's Straits.

Sertularella polyzonias and Scrtularia operculata seem to be the two
British species which have the widest range.

INTRODUCTION.

associate themselves with certain kinds of mollusk. Tlic
peculiarities of habitat arc very curious, and must be learnt
by observation and experience.

The littoral Hydroids must be sought in the tide-pools,
both large and small, in the chinks and crannies of the
rock, on the underside of stones, and beneath the hanging
weed. I have described elsewhere (vide p. 298, note) the
method of search which is most likely to prove successful
in the case of the minuter species, and the apparatus
which is requisite. Of course a vast deal may be done in
a more "easiful" way; but the collector will find an ample
reward for his labour, whatever it may be, in the beauty
of the scenery which it will open to him, and the interest
of the material which he will gather.

The larger Sertularian zoophytes, whose graceful plant-
like forms are so familiar, can only be obtained in the
living state by means of the dredge ; but the horny ske-
letons may be gathered on most sandy beaches, and fre-
quently in great profusion, after stormy winds. Large
tangled masses of them, which are full of beauty in them-
selves, are cast ashore, and if examined while still fresh
and moist will often be found to conceal some of the
smaller kinds in a living state. The dredge, indeed, is
essential to those who would thoroughly investigate the
Hydroida ; but rich material for study and a great variety
of forms may be obtained on the shore.

The free medusiform zooids may be captured with a hand-
net from the rocks, or by means of a tow-net from a boat,
especially in still, warm autumn weather, when they swarm
near the surface of the sea. They are difficult to keep ;
and few have as yet succeeded in obtaining and hatching
the ova, and tracing the development into the polypite

d

1 INTRODUCTION.

form. Those who have the opportunity will do well to
take up this line of investigation, which promises to yield
the most interesting results. The reproduction and de-
velopment of the Hydroida may be studied with great
facility in many of the littoral species of Coryne, Syncoryne,
Perigonimus and Tubularia. The ubiquitous Obelia geni-
culata may always be readily obtained in summer with its
capsules, within which the gonozooids may be watched
through all the stages of their development, and from
which they may be seen escaping in numbers.

The larger and stouter species of Hydroida may be pre-
served by drying ; but even these lose much of their beauty
in the process. The Campanulariidte should be kept in
fluid*, as their calycles shrivel up when dried. The
Athecata generally must also be preserved in the same
way, as the polypites, which exhibit many varieties, afford
important characters ; and the mere polypary without them
is, in a large proportion of cases, useless for the purpose of
identification. Specimens kept in fluid retain much of
their original beauty, though of course the exquisite
colours that adorn many species are lost.

But to appreciate fully the extreme loveliness of these
" animal-plants " they must be seen in life. A tuft of
Halecium or Eudendrium, the one laden with white, the
other with brilliantly tinted polypites, like blossoms on
some tropical tree, is a perfect marvel of beauty. The
unfolding of a mass of Plumularia taken from amongst the
miscellaneous contents of the dredge and thrown into a
bottle of clear sea-water, is a sight which, once seen, no
dredger will forget. A tree of Campanularia or Obelia,

* The best methylated spirit is a good and convenient preservative fluid.

INTRODUCTION. li

when each one of its thousand transparent calycles, itself
a study of form, is crowned by a circlet of beaded arms,
drooping over its margin, like the petals of a flower, offers
a rare combination of the elements of beauty.

The rocky wall of some deep tidal pool, thickly studded
with the long and slender stems of Tubularia, surmounted
by the bright rose-coloured heads, is like the gay parterre
of a garden. Equally beautiful is the dense growth of
Campanularia, covering (as I have seen it in Plymouth
Sound) large tracts of the rock, its delicate shoots swaying
to and fro with each movement of the water, like trees in
a storm — or the colony of Obelia on the waving frond of
the tangle, looking almost ethereal in its grace, trans-
parency, and delicacy, as seen against the coarse dark sur-
face that supports it.

But, besides the remarkable beauty, there is a charm in
the life-story of these beings. " There must always be a
certain fascination in a history which tells us of animals
composed of multitudes of individuals (zooids) living an
associated life, and so combining as to produce the most
graceful plant-like structures — vegetating like a tree —
putting forth thousands of polypites, like leaves, each a
provider for the commonwealth — putting forth also a com-
pany of buds, charged with the perpetuation of the species,
ripening in transparent urns and scattering their winged
seeds broadcast, or sent forth, moulded and painted by
the highest art, like fairy emigrant-ships freighted with
young life, to colonize distant seas. And these are the
simple facts of nature"*.

* Vide an article by the author, entitled " Zoophytes : the History of their
Development," in the Quarterly Journal of Science, vol. ii. no. 7, p. 416.

n INTRODUCTION.

BIBLIOGRAPHY.

It is unnecessary to give any extended list of works on
the Hydroida, as those who are studying the literature of
the subject will find full information in the ' Bibliographia '
by Agassiz, published by the Ray Society, the supple-
mentary volumes by Carus and Engelmann (Bibliotheca
Zoologica, 1848 to 1860), and the invaluable ' Record of
Zoological Literature/ issued annually under the editor-
ship of Dr. Giinther. A good list of Memoirs published
subsequently to 1860 is prefixed to the ' Catalogue of
North American Acalephee/ by Alexander Agassiz ; while
the well-known journal,, the ' Archiv fur Naturgeschichte/
contains a critical review of the Coelenterate literature of
each year by Prof. Leuckart, which is of the highest value
to the student. In Prof. Greene's < Manual of the Coelen-
terata ' there is also a list of some of the principal works
and papers on the Hydroida.

A selected list, which may answer the general purposes
of the student, is given at the close of the present work.

DICHOTOMOUS TABLES.

The following Tables are added to enable the student at
once to refer any species which he may find to its place.
It must be clearly understood that they do not represent
natural affinities and relationships, but are a purely arti-
ficial contrivance to save time and somewhat wearisome
labour. Having determined by their aid the genus to
which his zoophyte belongs, the student should refer to
the Synopsis of Families and Genera at the close of the
Introduction to learn its position in the natural system.

The characters on which the dichotomous division is

INTRODUCTION. Hit

based arc, as far as possible, such as may be easily recog-
nized. But the generic groups are frequently founded on
differences in the reproductive system only; and in such
cases it has been necessary to employ the gouozooid as
the criterion. For example, Coryne and Syncoryne are
identical so far as the trophosome is concerned, and are
distinguished solely by the character of the sexual zooids ;
in such a case, if the reproductive bodies have not been
observed, the only plan is to go through the species of the
two genera until we find the description that answers to
the form before us.

An illustration will best indicate the method of employ-
ing the Tables. Let Tubularia indivisa be the zoophyte
that wre wish to determine. It has a polypary, but no
calycles, and therefore belongs to the Athecate division
(Table I.) ; its polypites are associated, not solitary, and
therefore under Bracket 1 we are referred to No. 3 for
further information. Turning to Bracket 3 we learn that,
as it has tentacles of one kind only, we must pass 011 to
No. 7. Bracket 7 gives us the choice between capitate
and filiform tentacles; and, as our zoophyte has undoubtedly
the latter, we are referred to No. 11. There we at once
place it under the first division, " tentacles in two separate
circles," and are directed to No. 12, where we learn that
it is an Ectopleura if it has free gonozooids, and a Tubu-
laria if it has not. Should this point be undetermined,
we may turn first to the genus Ectopleura, and finding
that it contains but a single species, which is minute and
not clustered, we shall at once be guided to Tubularia as
our goal.

liv

INTRODUCTION.

TABLE I.— ATHECATA.

Hydroida with a polypary, but without true calych'S.

Genera.

i I Polypites solitary 2

' I Polypites associated 3

(Tentacles capitate and scattered

2. < over the body MYBIOTHELA.

( Tentacles filiform, in two circles , . COBYMOBPHA.

q j Tentacles of two kinds 4

1 | Tentacles of one kind 7

i Upper tentacles capitate; lower
without capitula, rigid 5
Upper tentacles capitate j lower
filiform and flexile 6

(Capitate tentacles in a single cru-
ciform verticil CLADONEMA.

' i Capitate tentacles in several cruci-
( form verticils STAUBIDIUM.

„ I Stem simple VOBTICLAVA.

' I Stem branched ACHABADBIA.

j I Tentacles capitate 8

' j Tentacles filiform 11

( Tentacles scattered or in several

8. < whorls 9

{ Tentacles in a single whorl CLAVATELLA.

n I With free medusiform gonozooids 10
' I Without free gonozooids COBYNE.

-,n \ Polypary composed of two coats . . ZANCLEA.

| Polypary simple SYNCOBYNE.

-, -, \ Tentacles in two separate circles . . 12
' | Tentacles scattered or in one circle 13

i i) \ With free medusiform gonozooids . ECTOPLEUBA.

| Without free gonozooids TUBULABIA.

13.

I Tentacles scattered 14

j Tentacles in a single verticil

17

INTRODUCTION.

Iv

Genera.

1 , i Polypites on a distinct stem 15

' ( Polypites sessile 16

; Stems a simple tube (or rarely with
a single branch) TUBICLAVA.
Stems much branched and plant-
like CORDYLOPHORA.

{ Tentacles few ; the four uppermost
long and erect TIRKIS.

Tentacles very numerous CLAVA.

I Polypites with a bilabiate mouth

17. < (and two tentacles) LAR.

( Polypites with a simple mouth . . 18

[Tentacles with bosses formed of
-. Q \ large thread-cells placed a little

' 1 above the base HYDRANTIIKA

(Tentacles without bosses 19

i q I Polypites sessile , 20

' | Polypites on a distinct stem 22

(Gonophoresborneonpolypiteswith-

')() 3 out tentacles 21

' j Gonophores borne on polypites with
( tentacles or on the adherent base PODOCORYNE and

CORYNOPSIS*.

( Polypites supported on a chitiuous

01 J and muricated crust HYDRACTINIA.

" ' i Polypites developed on a simple

( retiforni stolon CIONISTES.

I Polypites with a trumpet-shaped

22. <. proboscis EUDENDRIUM.

| Polypites with a conical proboscis . 23

( Body of polypite and lower part of
o., J tentacles covered by a membra-
" ' 1 nous sheath BIMKRIA.

( Polypites without such covering . . 24

Gonophores borne on polypites

24 without tentacles DICORYNE and HE-

Gonophores borne on the ccenosarc. 25 TEROCORDYLE.

1 More or less arborescent GARVEIA and Bou-

25. •! GAINVILLIA.

[ Small, and of simple habit AxRACTYLisand PE-

RIGOXIMUS.

* These genera diifer only in the character of the medusifonn zooid.

Ivi

INTRODUCTION.

TABLE II.— THECAPHORA.
Hydroida with true calycles.

Genera.

I Calycles erect aud free 2

1. < Calycles adnate, disposed along the
( stem and branches : 11

f * Calycles supported on a short pro-
cess from the stem ; polypitesonly

2.<( partially retractile 3

j Without the stem-process; poly-

t pites wholly retractile 4

I With snake-like tentacular organs
3. < distributed over the ccenosarc . . OPHIODES.

\ Without such organs HALECIUM.

{Calycles truly campanulate or bell-
shaped 5
Calycles not campanulate 6

t- I Calycles operculated LOVENELLA.

I Calycles not operculated ........ CLYTIA, OBELIA,

CAMPANULARIA,
THAUMANTIAS and

GONOTHYR^Af.

f Calycles ovato-conic J CAMPANULINA, ZY-

GODACTYLA,
OPERCITLARELLA,
and LEPTOSCY-
Calycles tubular or cylindrical. ... 7 PHTJS.

( Calycles with a conical operculum. 8
7. < Calycles without a conical oper-
( culum 9

{' Calycles constricted at the base and
pedicellate CALYCELLA.

Calycles not constricted at the base
and perfectly sessile CUSPIDELLA.

* The process immediately supporting the calycle or the jointed shoot
on which it rests is a projection from the stem. The calycles in this section
only shelter the base of the polypites.

•f In this group the trophosorne affords no generic characters. If the
reproductive bodies are absent, the student must treat it as a single genus,
and identify his zoophyte by a reference to the specific descriptions.

I The calycles in this section are more or less ovate, becoming pointed
above, where the margin is cleft into convergent segments. This form must
be distinguished from the long, tubular shape.

INTRODUCTION.

Ivii

Genera.

iCalycles united towards the base
by a cellular mass COPPINIA.

Calycles scattered 10

ICalycles rudimentary (exceedingly
short cylinders) TIMCHYDHA.

Calycles not rudimentary LAFOEA.

Without nematophores 12

With nematophores 18

[Calycles cylindrical, and disposed
jo J in longitudinal rows on all sides

' 1 of the stem SALACIA.

( Calycles otherwise disposed 13

iCalycles decumbent, scatteredalong
a creeping fibre (no erect stem).. FrLELLUM.

Calycles arranged in series along
the stem and branches 14

I , ( Calycles unilateral HYDRALLMANIA.

' | Calycles biserial 15

lg | Calycles immersed THUIABIA.

' } Calycles not immersed 16

Calycles decidedly alternate, with

a prominent operculum SERTULAEELLA.

Calycles without external oper-
culum 17

(Gonothecse (female) with a cleft

J margin and internal marsupium . DIPHASIA.

1 Gonothecse with a plain orifice and

( without marsupium SERTULARIA.

I With verticillate branchlets ANTENNULARIA.

I Without verticillate branchlets . . 19

(With a mesial neniatophore at-

n a J tached to the front of the calycle

1 Without a mesial uematophore at-

( tached to the front of the calycle

AGLAOPHENIA.

PLUMULARIA.

CLASSIFICATION.

It would be a fruitless labour to give any detailed
account of the earlier systems of classification, which have
now only an antiquarian interest. Those who are curious

Mil INTRODUCTION.

in such matters may consult Johnston's ( History/ where
they will find a careful review of all that had been done
in this department from the time of Ellis downwards — and
the third volume of Agassiz's ( Contributions to the Natu-
ral History of the United States/

Until a very recent period the real facts of the Hydroid
life-history had not been fully ascertained, and the basis
of a natural arrangement was therefore wanting. Even
when Johnston wrote the true nature of the medusiform
zooid had not been determined, and he followed Van
Beneden in regarding it as the embryo. At that time,
also, a very small number of the (so-called) rnedusoids had
been traced to their Hydroid stock, and the naked-eyed
Medusae were still treated as a group distinct from the
Hydroida. The accumulation of facts has proceeded
steadily since that period ; but the correct interpretation of
them and the elaboration of a really philosophical classi-
fication are amongst the latest results of research.

The Hydroid community presents two dissimilar ele-
ments, discharging respectively the functions of alimen-
tation and reproduction ; and in a large number of cases
these two elements separate from one another at a cer-
tain stage, and lead thenceforth an independent existence.
Before the connexion between these sundered parts was
recognized, and while they were only known as distinct
and dissimilar organisms, they were ranged under different
classes and distinguished by different names. A double
nomenclature was invented to designate what were only
fragments of one and the same individuality. Integral
portions of the same being were treated as if there were
no affinity between them ; and the zooid which had but
lately detached itself from the Hydroid stock, and would

INTRODUCTION. lix

soon lay the foundations of a new Hydroid colony, was
relegated in the systems of classification to a distance
from all its nearest of kin.

This primary and inevitable mistake has introduced a
large amount of confusion into this department of zoology,
and we are only now escaping, in part at least, from the
effects of it.

The most important result of recent investigation has
been the union of the Hydroid zoophytes and the naked-
eyed Medusae of authors in one great natural group. The
two forms of structure embraced in this division, the one
represented by the Hydra, and the other by the (so-called)
Jelly-fish, which appeared so dissimilar when only known
in isolation, are now proved to be essentially identical :
the fixed and floating polypites are but different phases of
one and the same organism. And these elements are
variously manifested and combined in the Hydroid
group. In some cases there are fixed zooids (alimentary
polypites) and free zooids (sexual polypites) developed from
the same stock, and constituting one (zoological) individu-
ality. In other cases there are two classes of fixed zooids,
the nutritive and reproductive, permanently united ; in
others, again, there are only free zooids (floating poly-
pites) in which the nutritive and sexual functions are
combined. But these are in reality nothing more than
variations of one and the same structural group.

There has been considerable diversity of opinion as to
the true position of the small number of medusan * forms
that are developed directly from the ovum without the
intervention of any fixed Hydroid stock. But they certainly

* This term is employed here and elsewhere as an adjective, descriptive
of a certain modification of Hydroid structure.

Ix

INTRODUCTION.

present no structural peculiarities that would entitle them
to stand alone, and are rightly merged in the Order, which
includes so many kindred zooidal forms. Agassiz and
Fritz Miiller have taken this view"; and Cams, in his
admirable classification of the Ccelenterata, has referred
them to the Hydroida, though he has placed them in a
distinct group (Haplomorpha) , apart from the forms into
whose life-history the two elements enter. Huxley pro-
poses a separate Order for the naked- eyed medusas that
are developed directly from the eggs of similar organisms ;
but the absence of the fixed-polypite stage can hardly be
accounted more than a generic character when it is re-
membered that the Lizzia observed by Claparede, the eggs
of which produce medusas,, is identical in structure with
the sexual zooid of the Campanularian LepioscypTms (All-
man). I can see no reason whatever for detaching the
medusan forms developed directly from the ovum, and not
as buds on a fixed stock, from the Hydroida, either as a
separate order, or even as a secondary section. To the
latter they are bound by the closest structural affinities ;
and instead of dismembering the Hydroid group on the
ground of this difference in the mode of development, it is
surely more philosophical to enlarge our conception of its
range.

I have therefore rejected Carus's subgroups Haplo-
morpha and Diplomorpha, and have preserved the simple
unity of the order Hydroida. The present work, however,
embraces only the medusan forms that have been traced
to a fixed Hydroid stock.

Another result to which we have been brought by our
increased knowledge of Ccelentcrate structure is the recog-
nition of the close affinity subsisting between the Siphono-

INTRODUCTION. Ixi

phora (Eschscholtz) and the Hydroida proper. The rela-
tionship is masked by the striking difference in habit and
general aspect between the two groups ; but the restless
ocean vagrants and the stationary, plant-like beings that
seem to offer the most complete contrast to them are
essentially identical in structure, and the leading pecu-
liarities of each group are only modifications of that
structure adapting it to various modes of life.

At certain points of the Hydroid series, the apparent
dissimilarity is much less marked ; and a colony of Hydr ac-
tinia or Podocoryne very plainly betrays its affinity to
Velella or Physalia.

Carus lias ranged the Siphonophora and the Hydroida
proper, as separate groups, under his order Hydromedusa.
Agassiz unites the two as a single order, constituting sub-
orders for the leading divisions of each.

Huxley, who is followed by Greene, divides the Sipho-
nophora into two groups, Calycophoridce and PhysopJioridce,
which he regards as orders of his Class Hydrozoa, parallel
with the Hydridce, Corynidcs, and Sertulariadae , and with
the Lucernariadce, including the covered-eyed Medusae of
Forbes*, and Lucernaria.

All these arrangements recognize the close affinity of
the Siphonophora and Hydroida, and differ only in the
details of their grouping.

In the present work the first three of Prof. Huxley's
orders, Hydrides, Corynida, and Sertulariada, are treated
as suborders, and constitute together the order Hydroida.

It seems to me clear that these divisions have no claim
to be considered groups of equal value with the Discophora
(Lucernariadce of Huxley) .

* Steganophthalmata, Forbes; Fhanerocarpee, Each. ; Acraspeda, Gcgon-
baur.

INTRODUCTION.

The Calycophorida and Physophorida I should also rank
as suborders,, and unite in the single order Siphonophora.
The Medusida of Huxley, under which he has ranged the
naked-eyed Medusae that have not yet been traced to a
Hydroid stock, and those which are known to be developed
directly from the ovum, according to the views already
stated, should cease to constitute a distinct group. For the
Steganophthalmata (Forbes) with Lucernaria, which form
the third of the orders of Hydrozoa, Discophora seems to
me a better designation than Lucernariada, which has been
adopted by Huxley, and which is derived from a strikingly
aberrant form.

In classifying the Hydroida and constructing the generic
groups, respect must be had, as emphatically pointed out
by Allman*, to both the nutritive and reproductive ele-
ments. It is much easier, however, to recognize the
correctness of this principle in the abstract than to apply
it practically to the work of the systematist; for the
affinities suggested by one of these elements are, in many
cases, by no means affirmed by the other.

The trophosomes of two species may agree very closely
in character, while the gonozooids are widely dissimilar,
and vice versa. To take a striking illustration : the repro-
ductive zooid of Corynopsis, a genus which ranks in the
family of the Podocorynidce, is identical when first liberated
with that of Bougainvillia, a member of the family Atrac-
tylida-\. So Syncoryne eximia and Stauridium productum,
which are referred to different genera from the dissimi-

* In bis valuable paper " On the construction and limitation of genera
among tbe Hydroida," Ann. N. H. for May 1864.

t By an error, Bougainvillia is referred, on page 35, to the family of the
Eudcndriidce.

INTRODUCTION. Ixiii

larity in the polypites, originate mcdusiform gonozooids
\vhicli are not merely alike, but identical at the time of
detachment*. In these examples the trophosomes are
dissimilar, whilst the gonosomes agree. But the cases are
much more numerous in Avhich the alimentary zooids
exhibit the closest relationship, while the gonozooids pre-
sent differences that would be commonly accounted generic.
Amongst the Corynidce, three genera (Coryne, Sijncoryne,
and Zancka] are undistinguishable one from the other, so
far as the trophosome is concerned. In the large and
beautiful family Campanulariidae, all the generic groups,
with a single exception, are founded on characters sup-
plied by the gonosome alone; and many similar cases
might be cited.

Perfect agreement in the alimentary characters does not
of necessity imply agreement in the sexual characters ;
whilst, on the other hand, the trophosomes may be
strikingly unlike, and the gonozooids identical.

Our system of classification must be harmonized with
these perplexing facts ; and it is hardly a paradox to say
that in some respects it may appear less natural if strictly
conformed to the order of nature.

It may be remarked, in passing, that in some genera
the differences between the species are chiefly exhibited
in the trophosome, and the gonozooids are almost, or alto-
gether, identical. This is remarkably the case in the

* A. Agassiz (in bis ' Cat. of North American Acalcphae, 1865) expresses
his belief that at a more advanced stage these gonozooids would exhibit diffe-
rences—and will not allow that " medusae generically identical " are " deve-
loped from Hydroids generically distinct." Since the publication of his
work, however, observations have placed it beyond doubt that many cases
occur in which the gonosomes are identical, while the trophosomes present
differences that must be accounted generic.

Ixiv INTRODUCTION.

genera Syncoryne and Periffonimus, and more or less so in
several others. In such groups the alimentary portions of
structure would seem to have been more susceptible of
modification than the reproductive.

In constituting the genera, I have endeavoured to give
due weight to the different structural elements. I have
followed Agassiz and Allman in regarding the presence or
absence of a free sexual zooid as a character of generic
value, though the adoption of this view leads to the sepa-
ration of species that in all else are most nearly allied.
But I must most strongly dissent from the practice of
those authors who have multiplied divisions on the ground
of slight variations in the gonozooid*.

The three suborders under which I have distributed the
British Hydroida correspond with the Tubularina, the
Sertularina, and the Hydrina of Johnston ; but I have-
thought it better to introduce significant titles for these
higher divisions rather than to ring the changes on the
names of the typical genera.

The character which distinguishes the first suborder,
Athecata (the naked condition of the polypites), is asso-
ciated with great diversity in the configuration of the body
and the structure and disposition of the tentacles. A rich
variety of shape and colour characterizes the polypites of

* There has been a tendency amongst some writers to pay almost exclu-
sive attention -to the medusan element, both in their description and classifi-
cation ; but the nutritive and reproductive structures are coordinate, and
due regard must be had to both, if we are to form a just conception of the
individual Hydroid, or of the affinities and relationships of the Hydroida.

On the subject of classification, reference may be made to two admirable
and exhaustive papers in the ' Natural History Review,' Nos. xi. and xii., for
July and October, 1863, which are devoted to a review of the 4th vol. of
Agassiz's ' Contributions,' and discuss very fully and with great ability the
various questions connected with the systematic arrangement of the Hydrozoa.

INTRODUCTION. 1XV

this division. Amongst the Thecaphora, on the contrary,
they exhibit very little variation, and the tentacles are in-
variably filiform and arranged in a single wreath. A like
uniformity prevails in the position of the gonophores
throughout the latter suborder; they are always borne
on a columnar offshoot from the coeuosarc, which is homo-
logous with the proliferous polypite amongst the Athecata,
whether fully developed or more or less atrophied.

The Thecaphora are remarkable for their plant-like
growth and the elegance of their forms. *

The following Table exhibits the scheme of classification
adopted in the present work : —

Subkingdom CCELENTERATA, Frey & Leuckartf.

Class HYUROZOA, Huxley.
Ord. I. HYDKOIDA. Ord. II. SIPHONOPHORA. Ord. III. DISCOPIIORA.

Order I. HYDEOIDA.

Suborder I.— A THE CAT A.

Hydroida destitute of true thecse or protective cases, either for
the polypites or g-onophores.

Family I. — Clavidse.

CLAVA, Gmelin.
TUBICLAVA, Allman.

TURRIS, Lesson.
CORDYLOPHORA, Allnian.

* These two suborders correspond with the Gymnogonial and Angiogoniul
divisions of Allman. The terms here employed seem to me to have tin's
advantage, that they are more general in their application, and may be taken
to apply both to the trophosorue and the gonosorne.

t Beitrage zur Kenntn. dcr wirbellosen Thicrc, von Frey u. Leuckart, p. 37.

Ixvi INTRODUCTION.

Family II. — Hydractiniidae.
HYDRACTINIA, Van Beneden.

Family III. — Podocorynidse.

PODOCORYNE, Sars.
CORYNOPSIS, Allman.

? CIONISTES, Wright.

Family IV. — Laridae.
LAR, Gosse.

Family V. — Corynidse.

CORYNE, Gaertner.
SYNCORYNE, Ehrenberg.

ZANCLEA, Gegenbaur.

Family VI. — Stauridiidse.
CLADONEMA, Dujarclin. ] STAURIDIUM, Dujardin.

Family VII.— Clavatellidse.
CLAVATELLA, Hincks.

Family VIII. — Myriothelidae.
MYRIOTHELA, Sars.

Family IX. — Eudendriidae.
EUDENDRIUM, Elireuberg.

Family X. — Atractylidse.

ATRACTYLIS, Wright.
PERIGONIMUS, Sars.
HYDRANTHEA, Hincks.
GARVEIA, Wright.

BIMERIA, Wright.
DICORYNE, Allman.
HETEROCORDYLE, Allman,
BOUGAINVILLIA, Lesson.

Family XI. — Tubulariidae.

TUBULARIA, Linn. CORYMORPHA^ Sars.

ECTOPLEURA, Agassiz.

INTRODUCTION.

Family XII. — Pennariidae.
VORTICLAVA, Alder. | ACHARADRIA, Wright.

Suborder IL— THECAPHORA.

Hydroida furnished with thecse.

Family I. — Campanulariidse.

CLYTIA, Lamouroux.
OBELIA, Per. & Lesueur.
CAMPANULARIA, Lamk.

LOVENELLA, HillclvS.

THAUMANTIAS, Escli.
GONOTHYR.EA, Allman.

Family II. — CampanuliiiidaB.

CAMPANULINA, Van Ben.
ZYGODACTYLA^ Brandt.

OPERCULARELLA, Hincks.

Family III. — Leptoscyphidse.
LEPTOSCYPHUS, Allman.

Family IV. — Lafoeidae.

LAFOEA, Lamouroux.
CALYCELLA, Hincks.
CUSPIDELLA, Hincks.

SALACIA, Lamouroux.
FILELLUM, Hincks.

Family Y. — Trichydridae.
TRICIIYDKA, Wright.

Family VI. — Coppiniidse.
COPPINIA, Hassall.

Family VII. — Haleciidse.
HALECIUM, Okcn. OI'HJODES; Hincks.

INTRODUCTION.

Family VIII. — Sertulariidae.

SERTULARELLA, Gray. | HYDRALLMANIA, Hincks.
DIPHASIA, Agassiz. " THUIARIA, Fleming.

SERTULARIA, Linn.

Family IX. — Plumulariidse.

ANTENNULARIA, Lamk.
AGLAOPHENIA, Lamx.

PLUMULARIA, Lamk.

Suborder III.— GYMNOCHROA.

Hydroida destitute of polypary ; locomotive.

Family I. — Hydridse.
HYDRA, Linnaeus.

Agassiz, on the strength of observations made on the
Millepora alcicornis, Linn., proposes to transfer to the Hy-
droida the coral-making group of the Tabulata, which has
hitherto ranked amongst the Actinozoa. He also conjec-
tures that the Rugosa of Milne-Edwards belong to the
class Hydrozoa.

BRITISH HYDROIDA.

Suborder L— ATHECATA.

Tum-LARiNA, Ehrenberg, Corall. des rothen Moeres, 70; Jolinston, Brit.

Zooph. i. 29.

CoRYNiD^E (order), Huxley, Oceanic Hydrozoa, 21.
TUBULARI.E, Agassiz, N. H. U. S. ir. 338.
G-YMNOTOKA (except Hyrlra), J. V. Cams, Handbuch der Zoologie, ii. f>f>0.

Family I. — Clavidae.

POLYPITES claviform or fusiform, ivith scattered filiform
tentacula.

Genus CLAVA, Gmelin.

Der. C'lava, a club.
CORYNA, Elirenberg, Corall. d. rothen Meeres, 69.

GENERIC CHARACTER. — Polypites clavate, contractile,
ivith many scattered smooth tentacula, rising from a filiform
stolon, sheathed in a chitinous polypary, which also invests
the base of the polypite : reproduction by means of fixed
sporosacs, borne singly or in clusters on the body, behind
the posterior tentacles.

B

Z CLAVID^E.

THE species of Clava are all strictly littoral, and are
found on stones and weed between tide-marks.

We are indebted to Dr. Strethill Wright* for correcting
the error of previous naturalists, who had universally de-
scribed the polypites of this genus as naked and single.
The polypary is slightly developed, forming a delicate
sheath round the creeping fibre, and rising into a little
cup at the base of the polypites.

Reproduction is dioecious, the male and female gono-
zooids being borne by distinct colonies. The gonophore is
of very simple structure, and destitute of investing capsule.
Each ovary produces one or two ova, which are developed
into ciliated planuloid embryos.

The genus has representatives in the New and Old
Worlds. It ranges to North America, and is widely dis-
tributed through the North of Europe, having been ob-
served in Norway, Denmark, the Faro Islands, the Skaga-
rack, the Baltic, and Belgium, as well as on our own
shores. It is not included in Sars's c Mediterranean Lit-
toral Fauna/ All the known species occur in Britain.

1. C. MULTICORNIS, Forskal.

HYDRA MULTICORNIS, Forsk, Descriptiones Animalium, &c., 131 ; and Icones

Berum Naturalitim, pi. 20. figs. B, b.
CORYNE SQUAMATA, Couch, Cornish Faun, iii. 11, pi. i. fig. 1 ; Van Bcneden,

Rech. sur les Tubulaires, 60, pi. v.
CLVVA MULTICORNIS, Johnston, Brit. Zooph. SO, pi. i. figs. 1-3.

„ REPENS, T. Strethill Wright, Eclinb. New Phil. Journ. (N. S.) for July

1857, pi. ii. fig. 1.
,, DISCRETA, AUman, Ann. N. H. Nov. 1859.

Plate I. fig. 1.
POLYPITES separate, ranged at irregular intervals along

* On Clava, Ed. N. P. Journ., N. S. vi. (July 1857).

CLAVA MULTICORNIS. O

the creeping filiform base, white, rose-, or flesh-coloured,
with numerous tentacles; GONOPHORES round, hanging
in many-pedicled clusters immediately behind the lower
tentacles.
Height about ^ inch.

AFTER much consideration I venture to assign For-
skal's name to the common Clava of our coasts, with
scattered polypites. I admit at once that it is difficult to
arrive at a conclusion, and that there is room for diversity
of opinion. Forskal's description becomes hopelessly
obscure at the very point where it should be clearest, and
I can only urge that the interpretation which I put upon
his words is as good as any other that can be offered. His
figure, however, though poor, seems to me intelligible
enough, and I have no doubt that it was suggested by the
present species. Probably he may have confounded, as
other naturalists have done, the scattered and the clustered
forms. The Hydra squamata of Miiller is one of the
clustered species, and both his description and figure are
excellent. It is desirable to retain for the science, if
possible, both these early and well-knoAvn names ; and I
therefore propose relying chiefly on the figure to connect
Forskal's with the scattered form, and to refer Miiller's
to one of the species with clustered polypites.

The number of arms in this pretty species, as amongst
all the Hydroids of this suborder, varies with age. It
ranges up to 30 or 40. The prevalent colour of the poly-
pites is a rich rose, and there are few more beautiful
sights of the kind than a fine colony of this zoophyte
overspreading the surface of some tide-pool stone. The
oral extremity is opake white. The anterior portion of the
body is endowed with great mobility, and materially
assists the tentacles in the capture of prey. The latter
are slightly enlarged at the tip, which is covered with

B.2

4 CLAVIDyE.

minute hairs — the palpocils, or organs of touch. The ex-
tremity of the tentacle possesses great prehensile power,
and the Annelid or small Crustacean which may come in
contact with it is at once made captive and firmly held
in spite of its struggles.

Hab. Generally distributed on our coasts, between tide-
marks, commonly on stone. It is abundant in Devon and
Cornwall, and has been noticed in the Frith of Forth
(Wright), the Orkneys (Allman), and in Shetland (A.M.N) .

2. C. SQUAMATA, Muller.

HYDRA. SQUAMATA, Muller, Zool. Dan. i. 3, tab. iv. figs. 1-3.
CORYNE SQUAMATA, LcimJc. An. sans Vert. (2nd edit.) ii. 73.
CLAVA MEMBRANACEA, T. S. Wright, Ed. New Phil. Journ. (N. S.) for July
1857, pi. ii. figs. 2, 3.

Plate I. fig. 2.

POLYPITES in dense clusters, springing from a crust com-
posed of delicate membranous tubes agglutinated together,
tall, expanding above, of a rich reddish tint, with nume-
rous white tentacula, the clusters united by a simple,
filiform stolon ; GONOPHORES forming a broad and very
prominent collar round the body.

Height of the polypites in extension from half an inch to
an inch.

I HAVE little doubt that this form, which has been cha-
racterized by Wright under the name of C. membranacea,
is the Hydra squamata of Muller. In all important points
it agrees with the species so well described in the ' Danish
Zoology ;' and even the peculiar character of the crust is
indicated, when the author says of the polypites, "ope
microscopii ex materia mucida fucum vestiente, ortum
sximere videntur." Muller found his Hydra on the Fucus

CLAVA C011NEA. 5

vesiculosus; and this seaweed is the common habitat of
the British species that I have identified with it.

In C. squamata the polypites are closely massed together,
and form colonies on the fronds of the Fucus, the larger of
Avhich measure about half an inch across. They are tall,
and expand from the base upwards, thickening considerably
towards the tentacles. Under the microscope the body
appears lineated longitudinally, especially in the older
polypites. The tentacles are pellucid white, and number
about twenty in the adult *. The gonophores hang in
large bunches below the posterior tentacles, and form a
massive and conspicuous collar. Individually they are of
considerable size, and almost spherical in form.

The crust that supports each colony is made up of many
tubes massed together ; and the upper surface of it is com-
pletely covered with the cup-like extensions of the poly-
pary, from which the polypites rise ; these give it a honey-
combed appearance when the polypites are removed. The
tubes are of extreme delicacy, and composed not of solid
chitine, but of a soft membranous material. The colonies
do not generally stand alone : the tubular basis sends oft'
slender, filamentary prolongations, which creep along the
weed and give rise at intervals to new clusters.

Had. Queensferry, Firth of Forth, on Fucus vesiculosus
(T. S. W.) : Lerwick, low water, on the same weed (A.M. N.) .

[Denmark, on Fucus vesiculosus (Miillcr) .]

3. C. CORNEA, T. S.Wright.

Eclin. New Phil. Jouni. (N. S.) for July 1857, pi. ii. fig. 4.

Plate I. fig. 3.

POLYPITKS clustered, slender, slightly tapering, of a rc<idis1i-

* Muller jiive.* I lie number 0-10.

6 CLAVID^E.

brown (?) colour, with about 20 white, tapering ten-
tacula, borne on an adherent crust, composed of chitinous
tubes cemented together into a solid plate ; GONOPHORES
in rather small bunches, forming a somewhat narrow
ring round the body.

C. CORNEA is a smaller and slighter species than the
preceding. The polypites are more delicately formed and
want the broad expansion towards the upper part of the
body; they taper gradually, and not very markedly,
downwards. I can only speak doubtfully of the colour,
as I have not examined living specimens; but I should
judge it to be a reddish brown. The clusters appear much
less dense and massive than those of C. squamata. This is
due not only to the fact that the polypites are less closely
packed together, but also to the inferior size of the belt of
reproductive buds, which is enormous in C. squamata, and
of very moderate dimensions in the present species. I
have not noticed the lineated appearance in the polypites
of C. cornea. The crust is a solid chitinous plate, of a
decided horn-colour, made up of many tubes intertwisted
or laid side by side, and cemented together. The tubes
are larger and made of much firmer material than those of
C. squamata.

The two species, though allied, differ Avidely in general
aspect, as well as in the details that have been referred to.

Hob. The Orkneys, on Fucus (Goodsir) : Scotland, on
seaweed (Prof. Wyville Thomson) .

4. C. LEPTOSTYLA, Agassiz.

Contributions to the Nat. Hist, of the U. S. iv. 218, pi. xxi. and fig. 32, p. 222.

Plate II. fig. 1.
POLYPITES set closely together, forming moss-like bunches

CLAVA LEPTOSTYLA. •

on the creeping stems, which are usually agglutinated
together in a mass, very tall and graceful, the body much
attenuated for a short distance (about ^ of an inch)
above its origin, after which it suddenly increases in dia-
meter to about three times that of its base, and rises
to the height of half an inch in full-grown specimens,
with a very slightly tapering outline; tentacles not
less than 35 in the adult, arranged in a close
spiral, tapering, pointed, very long, and slender; GONO-
PHORES round, forming compound raceme-like bunches,
which sometimes occupy one-third of the length of the
body, but more commonly are croAvded at the upper
part.

THE above description is based on the account of this
species given by Agassiz in his great work on the Natural
History of the United States. I owe it to the kindness
of Mr. F. H. West, of Leeds, that I am able to make this
interesting addition to our British list. He was good
enough to send me some time ago a very fine specimen of
a Clava, which he had obtained from Morecambe Bay.
The remarkable size and gracefulness of the polypites at
once arrested my attention ; and a little examination dis-
closed the slender and stalk -like base of the body, which
is so marked a character of the C. leptostyla. This speci-
men, which formed a crowded colony on the surface of a
muss el -shell, lived with me for some time, so that I was
able to make careful observations upon it ; but, unfortu-
nately, my notes have been mislaid, and I retain little but
the general impression of its striking beauty. I add a few
particulars, taken from Agassiz's detailed description : —

" The creeping stems are usually so closely interwoven
and agglutinated to each other by their horny sheaths
that, owing to the density of the mass, they cannot be
easily distinguished as tubular bodies; but upon the out-

8 CLAVID^.

skirts of the group, where they are youngest, each one
may be traced separately."

The polypites are "highly contractile, and capable of
assuming a variety of shapes." When very lively the
body " is stretched to the utmost, with elongated head and
extremely attenuated tentacles ; at other times . . . the
head is depressed to a flat-topped disk, from which the
tentacles radiate nearly in one plane, like the spokes of a
wheel." " When disturbed, the whole body assumes the
most contracted condition; the stem and head shorten,
and the tentacles retract towards their bases, even to such
an extent as to be only three times longer than thick,
whilst the inner surface of the chymiferous cavity becomes
deeply plicated in obliquely transverse folds, which look
like spiral semipartitions." This was very apparent in
my specimens*.

The gonophores are borne on pedicels, 10, 15, 20, or 25
of which " spring from a large, thick and short peduncle,
which projects directly from the sides of the body. This
form of grouping may be compared to a very short raceme,
as the term is used in reference to plants. Usually these
bunches are attached to the stem, nearly on the same
level, and just below the tentacles; but frequently the
crowded groups extend downward, either continuously or
in detached masses, over one-third of the distance towards
the base/3

Agassiz speaks of Clava leptostyla as forming "little,

* Montagu, in an unpublished work now in the possession of the Linnean
Society, mentions a similar peculiarity as presented by a Clava which he
identifies with the Hydra squamatu, and had found on the leaves of Fucus
vesiculosus in the estuary of Kingsbridge, South Devon. " When examined
by a lens," he says, " the intestinal canal is observed to be undulatory or
spiral, and appears to be the coloured part of the body, the exterior part
being hyaline." This is the only record, I believe, of the occurrence of a
clustered Clam in Devon ; and it is not improbable that the species observed
by Montagu was the C. leptosfyla.

CLAVA DIFFUSA. 9

red, moss-like bunches " on Fucus vesiculosus at low-
water mark, where they are exposed to the dash of the
breaking surf.

Hal). On a mussel-shell from Morecombe Bay (F. II .

West) .

[North America (Agassiz).j

5. C. NODOSA, T. S. Wright.

" Observat. on British Zoophytes and Protozoa," Edinb. N. Phil. Journ.
(New Ser.) xvi. 154.

POLYPITES single, small, aurora-coloured, each springing
from a small knot of convoluted tubes ; POLYPARY mem-
branous.

"THE very delicate threads of the polypary creep over
the fronds of the seaweed, and at intervals twine them-
selves into a convoluted knot of membranous tubes, from
which a single polyp arises. This species occurs only at
low-tide mark, while C. repens [inulticornis] , for which it
may be mistaken, is found in shallow rock-pools" (T. S. W.).
Hab. On the fronds of Delesseria sanguined, at Queens-
ferry and Largo (T. S. W.).

6. C. DIFFUSA, Allman.

Ann. & Mag. N, H. (3rd .ser.) xi. 8 (Jan. 1863).

POLYPITES very slender, of a light rose-colour, developed at
intervals upon a reticulated stolon; tentacula about 20,
CJOXOPHORES scattered, some produced just behind the
posterior tentacula, others extending singly or in small
clusters for some distance backwards upon the body of
the polypitc.

Height about | inch.

I GIVE this species on the authority of Prof. Allman, and

10 CLAVID^E.

must confess to some doubt as to its validity. The prin-
cipal character that separates it from C. multicornis is the
diffusion of the reproductive bodies. But this occurs
occasionally in other species, and can hardly be accounted
a character of much significance. Muller* represents
such a condition in his figure of the Hydra squamata ; and
Agassizf, in his account of Clava leptostyla, says that the
bunches of reproductive buds frequently extend doAvnward,
either continuously or in detached masses, over one-third
of the distance below the base of the tentacles. Possibly
we may have in C. diffasa a species of which this is the
normal and constant characteristic ; but at present I am
inclined to regard it as a mere variety.

It is right to add that Prof. Allman found the clusters
of gonophores scattered in all the zooids of the colony which
he examined. The polypites, too, were attenuated, and of
a delicate rose-colour.

Hab. In rock-pools at low water of spring tides. Out-
skerries, Shetland Isles (G. J. A.) .

Genus TUBICLAVA, Allman.

Der. Tubus, a tube, and Clava, the name of a Hydroicl genus.

GENERIC CHARACTER. — Stems erect, simple or branched,
given off at intervals from a creeping stolon; the whole
ccenosarc invested by a polypary ; polypites claviform, with
scattered filiform tentacula : reproduction by means of fixed
sporosacs, borne in clusters on the body of the polypite}
immediately behind the posterior tentacula, or on the sum-
mit of very short stems developed on the creeping base.

THE genus Tubiclava is most nearly allied to Clava.

* Zoologia Danica, pi. iv.

t N. H. United States, vol. iv. p. "2'22, fig. &.'.

TUBICLAVA CORNUCOPIA. 11

It differs from it in having the polypites elevated on dis-
tinct stems, clothed with a polypary. There is also, as
Prof. Allmaii has remarked, an affinity between it and
Cordylopliora.

I have so far modified the diagnosis as to make the
genus include the T. cornucopia, Norman, and have given
the grounds of the change in my account of that species.

1. T. LUCERNA, Allman.
"Notes on the Hydroida," Ann. N. H. (3rd ser.) xi. 9 (Jan. 1803).

STEMS quite simple, or rarely with a short lateral branch ;
polypary corrugated, dilated at the base of the polypitc,
pale yellowish brown ; POLYPITES when extended about
equal to the stem in height, white, with pale-ocJtreous
centre ; tentacula about 20, confined to the anterior third
of the body ; GONOPHORES borne in clusters behind the
lowest tentacles, and exactly resembling those of Clava.

Zoophyte about 2 lines in height.

Hab. Creeping over loose stones in a rock-pool, Torquay :
on stones between tide-marks, Dublin Bay (Of. J. A.).

2. T. CORNUCOPI/E, Norman.

TUBICLAVA CORNUCOPIA, A. M. Norman, Ann. N. II. (3rd ser.) xiii. 82 (Jan. ..

1864), pi. ix. figs. 4, 5.
MKRONA CORNUCOPIA, Norman, Ann. N. H. (3rd ser.) xv. 202 (April 1805).

Plate II. fig. 2.

STEMS about a fifth of an inch in height, invested by
a small trumpet-shaped tube, very slightly curved,
which is somewhat transparent and more or less encir-
cled by raised lines of growth ; POLYPITES greatly elon-

12 CLAVLD^E.

y cited; tentacles numerous, scattered over the whole of
the club-shaped head; GONOPHORES in mulberry-likemasses,
borne on very short stems, which are situated in openings
in the creeping base (rudimentary tubes}.

MB. NORMAN has, with considerable hesitation*, consti-
tuted the genus Merona for the reception of this species
at the suggestion of Prof. Allman. The only difference
between it and Tubiclava is to be found in the position of
the sporosacs, which, instead of forming clusters on the
body of the ordinary polypites, are massed together at the
extremity of short stems (yonoblastidia] .

The character of the polypary, of the polypites, and of the
sporosacs themselves is identical in the two, and I confess
I am unable to see any sufficient ground for separating
them.

The degree in which the fertile polypite may be atro-
phied in the discharge of its functions does not seem
to be a point of much significance. In some cases it is
fully developed at first, but the head and tentacles are
absorbed as the reproductive bodies advance towards
maturity, and it is converted into a (so-called) gonoblas-
tidiam. In Eudendrium capillare (Alder) the male spo-
rosacs at least always occur in umbelliform clusters ; yet
Prof. Allman himself has abandoned the genus Corymbo-
gonium, which he had based on this peculiarity. Tubiclava
cornucopia bears much the same relation to T. lucerna
' as E. capillare^ does to the members of its genus which
carry the sporosacs round the base of a perfect polypite,
and should not be separated from its true kindred on the

* "It. . . . still appears to me questionable whether the exact position
of the gonophores is a sufficient ground on which to establish a genus."
—Ann. N. H. for April 1865.

t The Etidendrii'.m fti-ln/H-nla (Wright) and other species present the
i-amc structure as E. capillare.

TURRIS NEGLECTA. 13

ground of this trifling difference. If the genus Merona
were adopted, we must dismember the very natural group
of forms now included under the genus Eudendrium.

Hub. " Tubiclava cornucopias was dredged in from 80 to
100 fathoms, about 20 miles north of CJnst in Shetland,
and was parasitic on the shells of Astarte sulcata and Den-
talium entails. It is worthy of remark that in every
instance the Hydrozoon was observed upon shells still
occupied by the living Mollusca, and that it invariably had
assumed a position at the posterior extremity of the shell,
where it would receive the benefit of the aqueous currents
caused by the mollusk, which, while providing for its own
necessities, thus unwittingly performed the kindly office of
feeding its hungry neighbour " (Norman) : coast of Nor-
thumberland, "on the posterior end of a Dentalium en-
talis " ( J. A.)

Genus TURRIS, Lesson.

Der. Turris, a tower.

GENERIC CHARACTER. — Stems short, rooted by a filiform
stolon, bearing the polypites on their summits ; the ccenosarc
invested by a polypary ; polypites claviform, with scattered
filiform tentacles.

Gonozooid free and medusiform. Umbrella subcylin-
drical, with 4 or 8 longitudinal bands ; manubrium massive,
four-lipped ; radiating canals 4 ; marginal tentacles nu-
merous, each with an ocellated bulbous base.

T. NEGLECTA, Lesson.

TURIUS N-EGLECTA (the free zooid), Lesson, Prodr. No. 38 ; Acal. Hist. 284 ;
Forbes, Brit. Naked-eyed Medusa1, 23, pi. iii. fig. 2 ; Gosse, Devonsh.
Coast, 348, pi. xiii. figs. 6-10 ; AHman, Ann. N. H. (3rd ser.) xiii.
3;r>2 (May 18fi4).

14 CLAVIDzE.

CYAN.EA COCCINEA (free zooid), Davis, Ann. N. H. vii. (1841) 234, pi. ii.

fig. 1,2,3.
CLAVULA Gossn (the polypite), T. Strethill Wright, Edin. New Phil. Journ.

(N. S.) for July 1859, pi. yiii. fig. 1.

Plate III. fig. 1.

POLYPITES minute, of a crimson colour, borne on short
stalks, which rise at intervals from the creeping stolon ;
tentacles about 12, the upper row long, four in number,
erect, the rest scattered, shorter, inclined upwards.

GONOZOOID. — UMBRELLA, in the mature zooid, subhemi-
spheric, slightly pointed above, transparent, smooth, with
four longitudinal bands ; MANUBRIUM of a rich crimson
when laden with the ova, — the mouth with four lips,
which are fimbriated at their edge; MARGINAL TENTACLES
more than 60 in number, closely set, very contractile,
each of them springing from a large bulbous base, on the
upper part of which is a brilliant crimson ocellus.

THE sexual zooid of this species has long been known,
having been described by Lesson in 1837 as an indepen-
dent animal. Forbes gives it a place amongst his naked-
eyed Medusae, and celebrates its beauty. In its native
element it "is brilliant as a bead of brightest coral." Mr.
Gosse obtained the first clue to its history in 1852, having
observed the escape of the embryos from the ovary and
their subsequent development into minute polypites. Dr.
Wright was afterwards fortunate enough not only to rear
the polypites, but also to keep them until they had attained
their perfect form. We are still ignorant of the position
in which the reproductive bodies are developed, and of
their early history.

The embryo is oval, dark crimson in colour, and ciliated.
After becoming attached it is developed into a branching
stolon, from which perpendicular stems originate, bearing
polypites with four long and straight tentacles. The further

CORDYLOPHORA. 15

change consists in an increase of the number of arms,
which are scattered over the body as in Clava.

Hab. In the Solent and around the Isle of Wight, not
uncommon : the West Bay of Portland (Forbes) : Tenby
(Dr. J. F. Davis); Ilfracombe (Gosse): Queensferry, Firth
of Forth (T. S. W.).

Genus CORDYLOPHORA, Allman.

Der. Kop3u\?), a club, and ^optw, I bear.
SYNCORYNA, Agassiz, N. H. U. S. iv. 339.

GENERIC CHARACTER. — Stem well-developed, branching,
rooted by a filiform stolon ; the whole of the ccenosarc in-
vested by a chitinous polypary ; polypites fusiform, deve-
loped from the extremities of the branches, with scattered
filiform tentacula : reproduction by means affixed sporosacs,
borne on the stem, never on the polypite.

THE genus Cordylophora is peculiarly interesting, as con-
taining the only composite Hydroids that have been found
in fresh water. It seems, however, to be equally at home
in brackish water. The C. albicola (Kirchenpauer) grows
on buoys at the mouth of the Elbe ; and Lindstrom. has
obtained C. lacustris in the half-saline waters of the Baltic
amidst a curious assemblage of marine and fluviatile
plants and animals. In this locality it grows on the stems
of Myriophylla. Paludina impura, fresh-water Entomos-
traca, and the larvre of insects abound. Associated with
these is the Corophium longicorne, an undoubtedly littoral
form, while the Tergipes lacinulatus, a thoroughly marine
Crustacean, creeps in numbers amongst the branches of
the Cordylophora*.

* Vide a paper by Lindstrom on "the Invertebrate Fauna of the Baltic,"
in iho ' (Efversigt af Kongl. Vetensk.-Akad. Forhandlingar ' for 18f>5.

IH CLAVID^E.

The genus occurs in North America, Prof. Leidy having
discovered another species, according to Agassiz, in New-
port Harbour, R. I.

Van Beneden has recently studied C. lacustris, and sup-
plies some curious illustrations of the voracity of the poly-
pites and their power of dealing with their prey.

Having put some water-fleas (Daphne) into the vessels
containing the Cordylophora, he was surprised in a short
time to see these active Crustaceans struggling amongst
the arms of the polypites, and soon losing their power of
motion, and lying, as it were, paralysed in their solid
carapaces. He has also seen worms (Nais) and Planariee
seized and devoured. The former, though very tenacious
of life, yielded rapidly to their assailants, and passed into
the digestive cavity of the polypites.

C. LACUSTRIS, Allman.

CoRDYLornouA LACUSTRIS, Allman, Ann. N. H. xiii. (1844) 330; Phil. Trans.

for 1853, 367, pi. xxv. and xxvi. ; Johnst. B. Z. 44, woodc.

fig. 5 : Hincks, Ann. N. H. (2nd scr.) ii. 180 (March 1853),

pi. vi. figs. 1, 2.
SVNCORYNA LACUSTRIS, Agassis, N. H. U. S. IT. 33(.i.

Plate III. fig. 2.

STEM slightly flexuous, more or less branched; branches
alternate, cylindrical, suberect, annulated above the
point of origin ; POLYPITES white, ovoid, prolonged above
into a conical proboscis, and supported on a fleshy neck,
to the base of which the chitinous polypary extends ;
tentacles 12-14; GONOPHORES oval, subsessile, invested
by a delicate chitinous covering, generally from one to
three on each branch.

Height between 2 and 3 inches.

THIS is the only composite and plant-like Hydroid which

CORDYLOPHORA LACUSTRIS. 17

inhabits our fresh waters. It has been thoroughly in-

o •,

vestigated by Allman, who has made it the subject of an
admirable memoir, which is one of the most important
contributions to our knowledge of the structure and
physiology of the Athecate Hydroida.

The polypitcs of Cordylophora, when kept in confine-
ment, soon perish, and are soon reproduced. They do not
drop off, like those of Tubularia, but are destroyed by a
process of absorption. The arms are roughened by thread-
cells, which are arranged in regular nodules. The poly-
pite, like the Hydra, possesses a remarkable power of
elongating and shortening its tentacles. At times they
are so much extended as greatly to exceed the entire body
in length, and in this state are attenuated into most deli-
cate filaments. When contracted they appear corrugated,
and comparatively thick.

The polypite is a singularly beautiful object when the
tentacula (some 12 or 14 in number) are all fully elon-
gated, floating like gossamer threads through the water,
and waving to and fro with its every slightest movement.

The reproductive buds are produced on the ultimate
ramules, at some distance behind the polypite. There are
sometimes as many as three on a branch, which are placed
alternately, "the more advanced being always nearer to
the main stems " ( Allman) . I have counted twelve ova
in a single female capsule, but more commonly the num-
ber amounts to six or eight. They are developed into
ciliated planulse, which escape through the ruptured
walls of the sac.

On reaching the water the embryo remains inactive for a
few seconds, undergoing remarkable changes of shape ; the
body then acquires a rotatory motion, and it sails off with
considerable rapidity. It is elongate-oval in form, somewhat
broader at one extremity than the other, opake white in

c

18 HYDRACTINIID^E.

the centre, and semitransparent toAvards the edge of the
body, and completely covered with cilia. Planulse which
had made their escape late in the evening, I have found
attached on the following morning. The cilia disappear,
and they fix themselves by one extremity, which expands
into a roundish disk, the body standing erect in the centre
of it. This gradually assumes the form of the polypite, the
upper portion becoming ovoid and pointed above. Three
or four tentacles also sprout from it, while the polypary
forms round the basal part. When the stem has reached
a certain height, it swells into small protuberances here
and there, which soon develope themselves into branches
and polypites. At the same time the base sends out
creeping shoots, from which fresh stems originate ; and the
process of germination continues until a whole forest of
plant-like structures has been evolved from the single
primary zooid.

Hob. On an old submerged boat, Grand Canal, Dublin
(G. J. A.) : in the Commercial and other Docks, London,
on wood, &c. (Dr. Bowerbank) : in a cistern at Kensing-
ton (Busk) : near Lynn Regis (Dr. Low) .

[G&lo-strat, Baltic (Lindstrom) : near Stockholm (Ret-
zius) : Schleswig (Van Beneden) .]

Family II. — Hydractiniidae.

POLYPJTES claviform, sessile, with a single verticil of fili-
form tentacles round the base of a conical proboscis,
borne on an expanded and continuous crust ; the cceno-
sarc naked above.

HYDRACTINIA. 19

Genus HYDRACTINIA, Van Beneden.

Der. Hydra, a genus of Hydroicla, and Actinia, a Sea-anemone.

EciiiNoc'iiORiUM, Hassall, Annals N. H. for July 1841.
SYNIIYDRA, De Quatrefages, Ann. Sc. Nat. xx. 232.

GENERIC CHARACTER. — Polypites claviform, sessile, with
a single verticil of filiform tentacula surrounding the base of
a conical proboscis, developed at intervals from the cosno-
sarc, which forms a naked expansion above, and below con-
sists of a mass of anastomosing stolonic tubes clothed with
a chitinous polypary, which are adnate to one another and
form a continuous crust : reproduction by means of fixed
sporosacs, which are borne on partially developed polypites*,
destitute of tentacles and furnished with many spherical
clusters of thread-cells round the oral extremity.

POLYMORPHISM reaches its height amongst the Hydroicla
in the genera Hydractinia and Podocoryne. In each
colony of these zoophytes several distinct kinds of zooid
with separate functions are united together, presenting a
wonderful variety of form and structure. We have in
Hydractinia, (1) the alimentary polypites, whose sole
office it seems to be to procure and digest nutriment for
the commonwealth; (2) the fertile polypites, which are
small and attenuated and only furnished with rudimentary
tentacles, and which support the true reproductive zooids ;
(3) the fixed reproductive sacs, which differ in shape and
colour in the two sexes ; (4) the spiral appendages, snake-
like organs, endowed with great muscular power, and
localized in certain regions of the common basal crust;

* This is not always the case. Gegenbaur mentions that he has found
gonophores on fully developed polypites (Grundziige der vergleichenden
Anatomic, p. 99, & p. 94. fig. 15).

C 2

20 HYDRACTINIID^E.

and (5) the tentacular filaments, highly extensile thread-
like processes with nematocysts at the tip, distributed
chiefly on the outskirts of the colony. In Podocoryne we
have, as a variation, a locomotive sexual zooid.

In studying these remarkable organisms, we are at once
reminded of the oceanic Hydrozoa, the complex colonies
of which float freely in the open sea. There are many
striking resemblances between Hydr actinia and some of
the Physophoridas. Both exhibit the same polymorphism ;
in both the reproductive bodies are borne on peculiarly
modified polypites; in both tentacular appendages are deve-
loped from the ccenosarc, and a solid expansion supports the
community. Hydractinia and Podocoryne, from the nature
of the habitat which they almost invariably select, enjoy
the benefits of locomotion, though themselves fixed. They
employ the mollusk and the Hermit-crab as their carriers,
and to some extent, probably, as their purveyors also.

The expanded crust of Hydractinia supporting the
curious assemblage of zooids has been investigated by
several eminent naturalists, from whom we have had con-
flicting accounts of its nature and the mode of its forma-
tion. Agassiz takes the view that the whole horny mass
is a " foot-secretion " just as truly as it is among the
gorgonioid polyps — an opinion which had been previously
maintained by De Quatrefages. Dr. Strethill Wright,
who has thoroughly investigated the history of Hydrac-
tinia, and who was the first to notice some of the most
interesting points of its structure, arrives at the opposite
conclusion, that the mode in which the polypary is secreted
is essentially the same as amongst other hydroid zoophytes.
There is some difficulty in examining the chitinous
expansion, closely adnate, as it usually is, to the body on
which the colony is planted. Frequently, however, in the
case of old shells tenanted by the Pagurus, it is found to

HYDRACTINIA.

21

extend for some distance beyond the edge of the shell, and
to form a considerable addition to the lip. This portion
can be readily removed and submitted to the microscope.
A careful examination of this free extension of the crust
has yielded the following results : — The upper surface is
invested by a white fleshy substance, from which the poly-
pites and spiral organs are developed in large numbers,
the latter almost exclusively on the extreme margin. On
examination, this soft layer is found to be mainly com-
posed of a multitude of delicate, anastomosing, tubular
stolons closely packed together. The surface of the layer
is more or less roughened by minute points of chitine,
which protrude through it, and, running in lines, mark
out the course of the stolouic tubes. At intervals large
grooved and muricated spines occur, which are also partially
covered by the fleshy crust.

If a portion of the base be divided transversely so that
the intimate structure may be examined in section, the
following appearances are observable.

Fig. 1.

A large proportion of the slice is seen to be occupied by
a chitinous framework (fig. I, a a), the upper side of
which is overspread by the fleshy carpet that bears the
polypites (fig. 1, b b}, while the inferior surface is more or
less covered by a thin layer of a mucus-like substance

22 HYDRACTINIID^.

(fig. I, c). The appearance of the framework itself as seen
in section is that of a series of tubes laid side by side 011
a plate of chitine, and closely appressed one to the other.

The tubular orifices are completely filled in with coenosarc.
Above they rise into many spinous projections so as to
exhibit a jagged outline ; below they rest uniformly on the
chitinous base. Here and there smaller spinous processes
are given off from the under surface of the latter, and pene-
trate the mucous layer that invests it.

The structure of the framework seems to be of this
kind. From a thin basal lamina of chitine rise numerous
chitinous lamellae, terminating above in serrulated edges,
which sometimes run parallel to one another and some-
times anastomose. The spaces between them form the
channels in which the soft cosnosarcal stolons are contained;
and from these rise the polypites and the spiral and ten-
tacular appendages. The passages or tubes thus formed
are covered in above, not by a solid wall, but by a chitinous
network, which stretches across them a little below the
free serrated edges of the lamellae.

Through the meshes of this fenestrated covering the
fleshy matter passes and forms a superficial layer, filling
in the grooves between the ridges and overlying the frame-
work, with the exception of the points of the spinules.

The larger spines owe their origin to the elevation of
the tubes at certain points.

The chitinous crust of Hydractinia, then, is in no true
sense a " foot- secretion ; " it is a modification of the ordi-
nary stolonic base of the hydroid zoophyte, and is secreted
in essentially the same way. The peculiarity consists in the
reticulated covering of the chitiuous tubes, allowing of the
outgrowth of the coenosarc and the consequent formation
of a naked superficial layer.

The mode of development will be understood by a

HYDRACTINIA ECHINATA. 23

reference to Plate IV. fig. 6, which represents a young poly-
pite in an early stage of growth. Before the formation of
the head and tentacles, radical prolongations are given off
at the base, which are the beginnings of the stolonic net-
work. The spaces between them are gradually filled in by
the extension of the coenosarc until they are almost united ;
but instead of coalescing, they seem to secrete on each side
of them the chitinous lamellae, the spinous ridges of which
soon show themselves on the surface * ; and the passages
thus formed are covered in by a reticulated roof. The
free investing layer of the coenosarc rests upon this roof
and conceals it.

In an early period of growth the base of Hydractinia
appears, according to Dr. Wright's observations, under
various forms, and, in some of the conditions which he has
described, resembles very exactly that of Podocoryne at a
corresponding stage. But the development of this portion
of the structure requires further investigation.

H. ECHINATA, Fleming.

AI.CYONIUM ECHINATUM, Flem. Brit. An. 517.

ALCYONIDIUM ECHINATUM, Johnst. Br. Z. (1st edit.) 304, pi. xlii. figs. 3, 4.

HYDRACTINIA LACTEA (the male), Van Sen. Tubulaires, 64, pi. vi. figs. 7-14.

„ ROSEA (the female), Van Ben. Tubul. 63, pl.vi. figs. 1-6.

ECHINOCHORICM CLAviGERUM, Hassall, Ann. N. H. July 1841, 371, pi. x. fig. 5.
SYNHYDRA PARASITES, Quatrefages, Ann. Sc. Nat. xx. 232, t. 8, 9.
HYDRACTINIA ECHINATA, Johnst. B. Z. 34, pi. i. figs. 4-6 ; T. Strethitt Wright,

Edinb. New Phil. Journ. (N. S.) for April 1857 ; idem, Ann.

N. H. for August 1861 ; Allman, Proceed. Eoyal Soc. Ed.

session 1857-58.
,, FOLYCLINA, Agossiz, N. H. U. S. iv. 227, pi. xvi. (vol. iii.) and

pi. xxvi. (vol. iv.) fig. 18.

Plate IV.
CHITINOUS CRUST covered with numerous grooved and

* Vide De Quatrefages on Synhydra, Ann. Sc. Nat, (2nd ser.1 Zool. xx. -M.">.

24 HYDRA CTINIID^E.

serrated spines; ALIMENTARY POLYPITES milk-white, with
a variable number of tentacula (20-30 in*. the adult),
which are held in extension, alternately elevated and
depressed; FERTILE POLYPITES short and slender, bearing
the gonophores in clusters or scattered upon the upper
portion of the body; GONOPHORES (male) oblong and
pointed above, of a yellowish colour, (female) roundish
and rose-coloured, — occasionally developed on the com-
mon base ; APPENDAGES OF THE CCENOSARC, long, filamen-
tary organs spirally coiled while at rest, with clusters
of thread-cells round the free extremity, and slender,
very extensile tentacula distributed singly 011 the out-
skirts of the colony.

H. ECHINATA selects for its habitat invariably, so far as I
have observed, univalve shells that are tenanted by the
Hermit-crab ; and there can be no doubt that its alliance
with the crustacean, though not essential to its wellbeing,
is at least the source of material advantage to it. I have
never found it in the situation in which Agassiz describes
his H.polyclina as frequently flourishing, on rocks in tide-
pools, where it sometimes covers, he says, "several square
feet with a rosy, velvet-like carpet," though it also occurs
on " the shells of Gasteropods, which serve as a retreat for
the Hermit-Crab." This zoophyte forms a whitish fleecy
covering on the shell of the mollusk, involving the greater
part of it when finely developed. The waving forest of
tall and graceful polypites generally reaches its greatest
height towards the mouth, round the edge of which are
set the curious snake-like appendages, either coiled up or
unrolled and cast out over the orifice like a fringe. Inter-
mingled with the perfect polypites, and commonly present
in immense numbers, are the rudimentary zooids, which
carry the generative sacs, attenuated by their work, and
looking as if weighed down by their burthen. Towards
the outskirts of the colony and along the growing edge of

HYDRACTINIA ECHINATA. 25

the crust, the polypites are of much smaller size ; aucl in
this region occur the tentacular filaments, which are
capable of great extension, and float like long fishing-
lines through the water. When not extended, these are
so inconspicuous as readily to escape observation. Rising
amongst the dense ranks of the polypites is a multitude of
serrated spines ; and supporting the whole array of curious
and beautiful structures spreads the common crust with
its soft overlying carpet of coenosarc.

A remarkable point in the history of the Hydractinia is
the amount of sympathy that exists between the zooids
composing a colony. This is due to the horizontal fleshy
layer which immediately connects them all. It has been
noticed that ift any part of the common base be irritated
the spiral appendages uncoil simultaneously, and lash
themselves violently backwards and forwards, and then
quickly roll themselves up again *. I have seen a whole
company discharge themselves with remarkable energy,
and with the precision of a regiment on drill.

After studying the structure and the singular associated
movements and the constant position of these bodies, I
have no doubt that Dr. Wright is correct in regarding
them as special organs of the zoophyte (" forms of a
truly definite nature"), notwithstanding the opposite de-
cision of Agassiz.

It is difficult to assign them a function, unless they be,
as Dr. Wright has conjectured, " organs of defence or
offence/5 They may, perhaps, be analogous in this
respect to the nematophores of the Plumulariida or the
curious tentacular appendages of Ophiodes.

* Vide a very interesting paper on Hydractinia in the Edinburgh New
Phil. Journ. for April 1857, by Dr. Strethill Wright, to whom we are in-
debted for the first notice of the spiral and tentacular appendages, and a very
accurate and philosophical account of the general structure of this zoophyte.

26 HYDEACTINIIDJ3.

If we direct our attention to the alimentary polypites,
we find that the proboscis is capable of extraordinary dis-
tention, and assumes the most protean forms. In its
most marked deviation from the normal condition, it pre-
sents the appearance of a wide saucer-like disk, the
tentacles standing out round the rim. In the prolific
polypite the buccal prominence is small and broadly coni-
cal, and is often concealed by the clustering masses of
thread-cells. I am inclined to think that the mouth is
not absolutely suppressed. Dr. Wright speaks of a
whitish spot on the tip of the proboscis, through which
he has succeeded in forcing " the contents of the intes-
tine ; " and Agassiz describes a mouth in his H. polychna,
a species which I am unable to distinguish from our own
H. echinata.

The sporosacs are distributed over the upper part of
the body, and attain an immense size as their contents are
matured. They are present in all stages of development
on the same polypite, one or two being generally much in
advance of the rest. The shape and colour vary in the
two sexes, the male sporosac being often much elongated
and of a vellowish tint, the female roundish and rose-

*

coloured.

H. echinata is liable to be infested by the larvae of a
Pycnogon, which manage in some way or other to take
possession of the polypites and convert them into nests, in
which they pass through certain stages of their develop-
ment*. These converted polypites are nothing more
than capacious sacs, without tentacles, in which, as in a
comfortable nursery, the brood of young Pycnogons spend
their early days, feeding 110 doubt on the nutrient juices
of the zoophyte.

* Vide a paper by Dr. Strethill Wright, Jouru. of Microscop. Science
(N. S.) vol. in.

PODOCORYNID.E. 27

Hab. On old univalve shells (Buccinum undatum, Fusus
corneus, Turritella communis, Nassa reticulata, Littorina,
Natica, Trochus zizyphinus, &c.) at low- water mark and
in deep water; generally distributed.

[Ostend (Van Ben.) : Normandy and Brittany, always
on shells tenanted by the Pagurus (De Quatrefages) :
North America (Agassiz) .]

Family III. — Podocorynidse.

POLYPITES sessile with a single verticil of filiform ten-
tacula round the base of a conical proboscis.

Genus PODOCORYNE, Sars (in part).

Der. Trof's, a foot, and Coryne, a genus of Ilydroids.
DYSMORPIIOSA, Philippi, Erichson's Archiv for 1842, 37, tab. i. fig. 3.

GENERIC CHARACTER. — Coenosarc consisting of a net-
ivork of creeping fibres, clothed with a polypary which also
forms a small cup-like investment round the base of the poly-
pites — the network in the adult state filled in ivith chitine,
so as to constitute a continuous crust ; polypites sessile,
claviform, with a single verticil of filiform tentacula
surrounding the base of a conical proboscis ; gonophores
borne on the body of the polypite below the tentacles,
or on the common basis, and originating free, medusiform
zooids.

Gonozooid : Umbrella bell-shaped ; manubrium shorter
than the umbrella, four-lipped, each lobe bearing a tuft of
vibratile thread-cells ; radiating canals 4 ; marginal ten-
tacles springing singly from bulbs ivithotit ocelli, the first

28 PODOCORYNIDyE.

set placed at the termination of the canals, the number
increasing with age, and always a multiple of four.

THE Dysmorphosa of Philippi is undoubtedly identical
with Podocoryne, and his name has precedence in point of
time. As, however, Sars's genus must be broken up into
two sections (the one including the species in which the
sexual zooids become free, the other those in which they
continue fixed), both names may be retained. I have
assigned Podocoryne to the former of these divisions, of
which the well-known P. carnea may be taken as the type.
The other should bear Philippics name *.

Under P. carnea an account is given of the mode in which
the common crust is developed in this genus. The early and
the later states are so different that they would probably be
referred to distinct genera if the intermediate stages of
growth had not been observed.

Krohn has described the budding of young from the
manubrium of the free sexual zooid, and A. Agassiz has
made similar observations on an allied species (Dysmor-
phosa fulgurans}. Development takes place with great
rapidity, and "buds of the third generation are already
forming while the second is still attached."

Agassiz mentions that the latter species is sometimes so
abundant that the whole sea, when disturbed, is brilliantly
lighted by the peculiar bluish phosphorescent colour which
it gives out f. We cease to wonder at the amazing num-
ber of these (so-called) Medusae when we know that thev
are not only thrown off by hundreds from each densely
packed hydroid colony, but that every one of them has the
power of producing a family by gemmation.

* Allman has proposed the name Stylactis for this section. But as he
now recognizes the identity of Dysmorphosa and Podocoryne, he will pro-
bably not deem it desirable to displace either of the older names.

t Catal. of North American Acalephw, p. 163.

PODOCORYNE CARNEA. 29

The first set of marginal tentacles consists of four, which
arc placed at the termination of the radiating canals.
The subsequent increase takes place by fours, the largest
number thus far observed in any species being 16.

Podocoryne rivals Hydr actinia in the variety of form
that exists amongst its zooids. The degeneration of the
fertile polypites is never so complete as in the latter genus,
and, indeed, in some cases it has no existence at all. I
have shown that the spiral and filamentary appendages
are common to both. There is a close relationship between
the two genera.

1. P. CARNEA, Sars.

PODOCORYNA CARNEA, Sars, Faun. Litt. Norv. part i. 4, t. i. figs. 7-18.

„ ALBIDA, Sars, ibid. 7.

PODOCORYNE CARNEA, Allman, Ann. N. H. for July 1859 and May 1864 ;
Hincks, Rep. Brit. Assoc. for 1864, (Proc. of Sect.) 99.

Plate V.

POLYPITES tall, expanding slightly upwards, white or red-
dish, with an opake-white proboscis, and a variable
number (4-30) of long and graceful tentacles, rising from
an iiicmsting base, thickly covered (in the adult state)
with smooth linear spines; GONOPHOHES borne in clusters
on the body of the polypites *, a little below the base of
the tentacles, pedunculate, containing each a single
medusiform zooid.

GONOZOOID. — UMBRELLA deep bell-shaped, thickly covered
with minute thread-cells, and with a wide velum ; MANU-
BRIUM short, reddish, with a tuft of large, vibratile
thread-cells on each lobe of the mouth; MARGINAL TEN-
TACLES eight, very extensile, springing from red bulbs,
four fully developed at the time of liberation, and four
more or less rudimentary.

* The fertile polypites are generally, but not universally, smaller than
the alimentary, and furnished with fewer tentacles (4-5).

30 PODOCORYNID^:.

WE have had conflicting accounts of this zoophyte from
authors, their discrepancies being due to the fact of their
having observed it in different stages of growth. Sars
describes the polypites as united together by a kind of
incrusting mantle, which after their death remains behind
' ' as a brown epidermal investment, bearing numerous
pointed spines of a horny nature/' Allman regards this
as probably a mistake, and characterizes the hydrorhiza
as simply tubular and retiform. But Podocoryne presents
us with both conditions. In its younger state the poly-
pites rise from delicate milk-white fibres, which run in
nearly parallel lines over the surface of the shell that bears
the zoophyte, and which are united by cross fibres, forming
at first a rather wide-meshed net. These cross fibres in-
crease in number and often anastomose, and gradually the
meshes are filled in by a chitinous crust, which appears to
involve the tubular basis itself. Numerous pointed spines
are developed simultaneously, as it seems, with the growth
of the crust ; at least I have never noticed them when the
stolonic network was perfectly simple. They are not muri-
cated, like those of Hydractinia, but smooth. In this way
the common base becomes a continuous expansion, thickly
studded with spinous processes, as described by Sars, on
which the polypites are densely crowded together. I have
specimens overspreading the shells of Nassa reticulata,
that exhibit the two conditions side by side. The delicate
milk-white network of fibres covers a considerable portion
of the surface ; but at certain points the meshes may be
seen partially filled in by the crust, while at others they
are converted into a solid expansion.

The stolonic portion, then, of Podocoryne cornea occurs
under the following forms : — (1) as a network of fibres of
greater or less complexity ; (2) as a network the fibres of
which are involved in a chitinous crust, which partially

PODOCORYNE CARNEA. 3]

fills in the meshes, and is set at intervals with spines ;
and (3) as a continuous crust bristling with spines.

These facts are interesting, not only as clearing up the
discrepancies in the accounts of the species, but as throwing
light on the formation of similar structures.

The polypites of P. carnea vary in colour ; they are
sometimes white or with a slight tinge of yellow, and
sometimes reddish. The proboscis is always opake white,
and at the base of it there is often a collar of deeper red.

There is no constant and uniform difference in size and
the number of tentacles between those which bear the
reproductive bodies and those which do not. Commonly
the prolific polypites are smaller than the rest, and are
sometimes much dwarfed and attenuated, the number
of arms being reduced to 4 or 5. But they occur with 7
or 8, 10, and even 16, and are not unfrequently fully
developed in all respects.

The gonophores are produced in large clusters, forming
a collar round the body of the polypite, some distance be-
low the tentacles. I have counted 6 in a group; and Sars
gives the number at 8—11.

At the time of liberation the four tentacles, which are a
continuation of the radiating canals, are fully developed,
and there is generally a smaller tentacle in the centre of
two of the interradial spaces. Two more soon bud from
the remaining spaces, so as to make the whole number
eight ; but 110 further increase has been observed.

The mouth is divided into four distinct lobes, each of
which is furnished with a tuft of thread-cells. These are
mounted on extremely delicate peduncles ; and when the
mouth is in search of food they are brought into an erect
position, and are in constant vibratile motion.

The gonozooid swims by a series of jerks or casts, and
carries the arms curled back over the bell.

32 PODOCOHYNID^E.

P. carnea is furnished with the curious spiral appendages
first described by Wright as occurring on Hydr actinia
echinata. They are placed in a row round the opening of
the shell that supports the hydroid colony, on the edge
of the investing crust, and are generally curled up in two
or three coils. They have a white central core, and are
very slightly enlarged at the free extremity. I have also
observed in certain portions of the colony slender filaments
springing immediately from the crust, wrhich correspond
with the tentacular appendages of Hydr actinia.

Hob. On stones in rock-pools near low-water mark, and
on old shells brought up on the lines of the fishermen, Inch
Garvie, Firth of Forth (G. J. A.) : on Nassa reticulata and
Turritella off Torbay in moderate depths, and in Swanage
Bay, Dorset : Oban, on operculum of Buccinwn (T. H.) :
Cullercoats (J. A.).

The shell of Nassa reticulata is the favourite habitat of
this species, and I have found it generally present on spe-
cimens taken up with the dredge. The main lines of the
creeping stolon usually follow with much regularity the
transverse sutures of the shell, the intervening spaces
being barred by the cross fibres previously to the consoli-
dation of the crust.

[Norway : Naples, in 10-20 fathoms, on shells tenanted
by the Pagurus (Sars) .]

2. P. AREOLATA, Alder.

HYDRACTINIA AREOLATA, Alder, Suppl. to Northumb. Cat. Trans. Tynes. Nat.

F. C. v. 225, pi. ix. figs. 1-4.
RHIZOCLINE AREOLATA, Allman, Ann. N. H. for May 1864.

Plate VI. fig. 1.

POLYPITES small, white, columnar, slightly enlarging above,
and terminating in a conical mouth; tentacles 6-10,

PODOCORYNE AREOLATA. 33

appearing of different lengths from their varying contrac-
tility ; the incrusting base from which the polypites rise,
a solid chitinous expansion"*, bearing simple linear spines
in groups, having areolar spaces between them ; GONO-
PHORES sessile on the base, large, globular, or slightly
pear-shaped, containing each a single zooid.

GoNozooiD. — UMBRELLA (at the time of liberation) sub-
globose, moderately deep, covered with thread-cells ;
MANUBRIUM rather long and columnar, but not extend-
ing beyond the margin of the umbrella; RADIATING
CANALS golden-yellow, continued by four rather short
marginal tentacles with bulbous bases, one to three
shorter tentacles in each interradial space, the number
varying with age.

Height of polypite about -^ inch.

PROF. ALLMAN has constituted for this species the genus
Rhizocline, which he ranks amongst the Hydractiniidce.
From this decision I am compelled to dissent. The H.
areolata of Alder is a true Podocoryne, presenting all the
essential characters of that genus as defined by its
founder, Sars.

The mere fact of its producing its gonophores on the
stolon instead of the body of the polypite cannot entitle
it to generic rank, for we meet with the same variation
within the limits of a species. Nor is there anything
peculiar in the nature of the incrusting base. Mr. Alder
describes it as a " solid chitinous expansion ; '' but in its
origin it is no doubt a reticulated stolon, the meshes of
which are gradually filled in with chitine, as is the case
in Podocoryne carnea^. The gonozooid of H. areolata
agrees with that of Podocoryne in all essential particulars.
In Mr. Alder's specimens the number of tentacles was 1G ;

* In an early stage this is probably represented by an open network,
t Mr. Alder agrees with me in my interpretation of this portion of (In-
structure.

1)

34 PODOCOllYNIDYE.

but Mr. Hodge, who has obtained the species at Seaham
Harbour, figures only 8, the largest number hitherto
observed on P. carnea. In both cases there is a progres-
sive increase with age, and as yet we do not know the
maximum with certainty.

I have therefore no hesitation in referring Mr. Alder's
Hydroid to the genus Podocoryne.

Hub. " On a dead shell of Natica Alderi, brought in by
the fishing-boats at Cullercoats" (J. A.) : on Natica
Grcenlandica, Shetland (A. M. N.) : Seaham Harbour, in
30 fathoms (Mr. Hodge).

Genus CORYNOPSIS, Allman.

Der. From icopvvri, a club, and oi^is, face (resemblance).

GENERIC CHARACTER. — Polypites sessile, claviform, with
a single verticil of filiform tentacula surrounding the base
of a conical proboscis, rising from a creeping and ramified
stolon, clothed with a chitinous polypary ; gonophores borne
on the body of the polypite below the base of the tentacles,
and originating free, medusiform zooids.

Umbrella of the gonozooid (at the time of liberation] deep
bell- shaped ; manubrium not reaching the orifice of the bell,
with 4 short tentacles round the mouth ; radiating canals
4, each terminating in a bulb, bearing two tentacles with a
distinct ocellus at the base.

C. ALBERT, Hodge.

PonoooRYNE ALDERI, Hodge, Trans. Tynes. Nat. F. C. v. 82, pi. ii. figs. 10-1").
CORYNOPSTR AUIF.RI, Allman, Ann. N. II. for May 1804.

Plate VI. fig. 2.

PoLYriTEs tall and slender, tapering towards the base, of
a pale pink colour, with 6 or 8 to 12 tentacles ; GONO-
PHORES produced at a short distance below the tenta-
cular verticil.

LARID^E.

35

GrONozooiD. — UMBRELLA (at. the time of liberation)
rather deeply campanulate ; MANUBRIUM short, of a pale
green colour; RADIATING CANALS terminating in con-
spicuous orange bulbs, each bearing two granulated
tentacles, with a deep-red ocellus at the base.

Height of the polypites i to i inch.

THE polypite of this species presents all the characters of
Podocoryne. The reproductive zooid is identical at the
time of detachment with that of the genus Bougainvillia,
which ranks amongst the Eudendriidae.

It is probable that it follows the same course of deve-
lopment, and exhibits, when mature, the branched oral
appendages and the marginal clusters of tentacles that
belong to the latter in its adult state. But the later
stages of its growth have not been observed.

Hub. Deep water, Seaham Harbour, Durham, on Ser-
pula (G. H.)-

Family IV. — Laridse.

POLYPITES with a very small number of filiform tentacula,
springing from the base of the proboscis, but not form-
ing a circle round it.

Fig. 2.

36 LAREDO .

Genus LAR, Gosse.

Der. Lar, a household god.

GENERIC CHARACTER. — Polypites fusiform, sessile, with
two tentacula springing from the base of a bilabiate pro-
boscis, developed on a creeping and anastomosing filiform
stolon* ; reproduction unknown.

WE require further information before anything can be
said with certainty of this extraordinary form. It has
only occurred in Mr. Gosse's aquarium, and its reproduc-
tive phase has not been observed.

LAR SABELLARUM, Gosse.

Transactions of the Linn. Soc. xxii. 113, tab. xx.

Woodcut, fig. 2.

POLYPITES about ^ inch in height, very slender towards
the base, enlarging above and terminating in a head-
like lobe, which is separated by a constriction from
the rest of the body; mouth furnished with two pro-
minent lips; tentacula long and muricated ; the ADHE-
RENT BASE a loose network of slender threads.

Mr. GOSSE describes the polypites as bearing " a most
ludicrously close resemblance to the human figure, and as
closely imitating certain human motions." They were
" incessantly bowing and tossing about their arms in the
most energetic manner/' Certainly if the figure from
which our woodcut is copied be not exaggerated, a Larite
colony must strikingly resemble a company of excited
gymnasts.

* This adherent base is probably enclosed in a delicate polypary ; but there
is no mention of it in Gosse's description.

CORYNID.E. 37

Allman says of the genus, " we are almost tempted to
regard it as an abnormal condition of some other form."
It must hold a provisional place until some new light is
thrown upon its history by further observation.

Hob. On a Sabella in Mr. Gosse's aquarium.

Family V. — Corynidae.

POLYPITES with capitate tentacula, scattered or in several
whorls.

G-enus CORYNE, Gaertner.

Der. Kopvi'tj. a club.

CAPSVLAUIA, Cuvier, Tableau elementaire, (i65.
STIPULA, Sai-s, Bidrag til Siidyrenes Naturhist. (1829).
SYNCORYNA, Ehrenberg, Corall. 70 (in part).
HERMIA, Johnston, Brit. Zooph. (1st eel.) 111.

ACROCIIORDIUM, Meyen, Nov. Act. Acad. Nat. Cur. 1834, xvi. 1(J5, tab. xxviii.
fig- 8.

GENERIC CHARACTER. — Stem simple or branched, rooted
by a creeping filiform stolon, the whole sheathed in a thin
chitinous tube, smooth or annul at ed ; polypites terminal,
clavate ; tentacles capitate, scattered over the body or in
several whorls ; reproduction by means of fixed sporosacs,
borne on the body of the polypite.

AMONGST the polypites which answer to Gaertner's de-
scription, two or three very distinct modes of reproduction
are met with, and it is therefore necessary to distribute
them into corresponding groups. His name is here em-
ployed in a restricted sense, to designate the species that
do not originate free medusiform zooids. The differences

38 CO11YNID.E.

between the present genus and Syncoryne are confined to
the gonozooids, the polypites of both presenting the same
characters. The list of synonyms must be understood to
apply to the two genera.

The Capsularia of Cuvier is probably identical with
Coryne as originally denned ; but his description is defec-
tive and obscure,, and his name has not been adopted by
subsequent authors. I therefore retain Gaertner's well-
established designation, though it is of later date.

There is still some uncertainty in the use of the name
by authors. Even so high an authority as Van Beneden
in his recent work follows Ehrenberg in making the Hydra
squamata the type of the genus Coryne. But this is quite
inadmissible, because (1) Gmelin had previously founded
his genus Clava for this form ; and (2) Gaertner, who ori-
ginated the name Coryne, applies it to a polypite with
capitate tentacles.

There is great difficulty in determining the synonymy of
the species of Coryne. I believe it to be quite impossible
to settle with any approach to certainty what the C\
pusilla of Gaertner was. The name has been applied to
many different forms, has almost been used as a general
appellation for everything corynoid, and it is a serious
question whether it would not be wise to discard it alto-
gether. As, however, it is old and familiar and finds a
place in every work on zoophytology, I have retained it,
and have connected it with a species that perhaps agrees
better than most with Gaertner's description and figure.
It is of the first importance that there should be fixity of
usage with respect to nomenclature, and I therefore hope
that this decision may be accepted as a starting-point for
the future.

We know but little of the geographical distribution of
this and the following genus. Two or three species have

C011YNE PUSILLA. 39

been observed in North America, one of which at least is
identical with a British form*. A single species from the
Pacific shores of the American continent (San Francisco)
has been published by A. Agassiz ; and I have met with a
minute species on gulf-weed, which I believe to be unde-
scribed. The genera are represented on the coasts of
Greenland, of Norway (to the North Cape), of Sweden,
and of Belgium by forms that occur in our own seas.

1. C. PUSILLA, Gaertner.

CORYNE I'USILLA, Gfierfno; in Pall. Spicil. Zool. fase. x. 40, tab. 4. fig. 8.
? Sv.NcoitYNALisTERii, Van Bcncdcn, Mem. sur Ics Tubul. 54, pi. iii. figs. 11, 12.
CORYNA GLANDULOSA, Daly ell, Bern. An. Scotl. ii. pi. xxi.
CORYNE RAMOSA, Alder, North. & Durli. Cat, in Trans. Tynes. P. C. iii. 102.
„ SESSILIS (young), Gossc, Devonsh. Coast, 208, pi. xiv. figs. 1-3.

Plate VII. fig. 1.

STEM rather stout, irregularly and sparingly branched ;
polypary of a dark horn-colour, closely and distinctly
cumulated throughout ; POLYPITE long, linear, very slen-
der, scarcely tapering towards the lower extremity, red-
dish ; tentacles very numerous (30 or more], rather long
and slender, and not expanded at the base, subverticil-
late ; GONOPHORES scattered over the body.

Height about an inch.

THE tentacles in C. pusilla are more truly whorled than
in any other species of Coryne, but the arrangement is by
no means perfectly regular. They are slender and fur-
nished with large capitula.

The ammlation of the stem is well-defined. The rings
are narrow, closely set, and not prominent. The branch-

* The Syndic? //OH, of A. Agassiz (North- Amer. Acaleplue, 177) is founded
on a small Corynoicl, obtained in Massachusetts J5ay and Eoston Harbour.
The dill'erenees between it and .s////cu/y///<' are confined to the sexual zooid.
and do not seem to be of generic value.

40 CORYNLD.E.

ing is simple and scanty. The tufts are of somewhat
spare and straggling habit, and have no tendency to
busliiness.

The linear figure of the polypites is a vrery marked
character. They are slender, of considerable length, and
of about equal size from one extremity to the other.

In some specimens I have noticed that the gonophores are
slightly pointed above, and I believe that this peculiarity
will be found to distinguish the male.

Sir John Dalyell's figure of Coryna glandulosa (Rem.
An. vol. ii. pi. xxi.) is an admirable representation of this
species. The C. sessilis (Gosse) is probably the young of
it. At Ilfracombe (Mr. Gosse's locality) I have frequently
found an unbranched and subsessile Coryne, agreeing very
closely with his figure, which was undistinguishablc from
the C. pusilla that was growing in the same pools.

It is impossible to make much of the synonymy. The
C. ramosa of Alder's Catalogue I know, from correspond-
ence with the author, to be identical with C. pusilla. Pos-
sibly so is the Stipula ramosa of Sars. Alder has identi-
fied the Syncoryna Listerii (Van Ben.) with the present
form, after the examination of specimens supplied by Van
Beneden himself. If this decision be correct the figure
in the ' Mem. sur les Tubulaires ' is very inadequate. In
his later work Van Beneden has assigned the name to
a different form, which seems to be the Syncoryne
Sarsii.

It were a hopeless task to attempt to clear up the confu-
sion that has been caused by the want of sufficiently
minute and careful diagnosis.

Hab. Scotland (Sir J. G. Dalyell) : in rock-pools, Tyne-
mouth (R. Howse) : Filey, Yorkshire : Ilfracombe, in
rock-pools (T. II.)

C011YNE VAGINATA. 41

2. C. VAGINATA, Hincks.

CORYNE, Lister, Phil. Trans, for 1834, 376, pi. x. fig. 3.

„ RAMOSA, Johnston, B. Z. 42, pi. vi. figs. 4, 5; Gossc, Devon. Coa.-i.

190, pi. ix.

?HEIOIIA r.LANDULOSA, Hassall, Ann. Is. H. for 1841, 283, pi. vi. fig. 2.
CORYNE VAGINATA, Hincks, Devon Cat. Ann. N. H. (ser. 3) ix. pi. vii. figs. 1,1 n.

Plate VIII. fig. 1.

STEM tall, branched, annulated throughout ; branches
given off on all sides of the stem, bearing polypiferous
ramuli ; POLYPITES fusiform, prolonged beloiv into a
slender neck, winch is invested by a delicate membranous
cup-like extension of the polypary, ringed like the stem ;
tentacles 15-20, or more, rather long and slender, bent
inwards when at rest, extremities rose-coloured.

GONOPHORES spherical, shortly stalked, produced in large
numbers over the greater part of the body.

Height 3 or ^ inches in finely grown specimens.

THIS is one of several species that have been confounded
under the name of C. ramosa. It is of tall and slender
habit, and somewhat irregularly branched. The polypary
is of firm texture and a decided horn-colour. The poly-
pites are slender and fusiform, tapering off towards the
mouth and downwards, and prolonged below into a narrow
neck of some length. The upper extremity of the body is
opake white, and the central portion of a reddish-brown
colour. The tentacles are commonly held curved inwards,
and have large, more or less deeply tinted roseate tips. The
portion of the polypary surrounding the slender base of
the polypite expands into a kind of cup, which extends
nearly to the lowest tentacles. It is composed of three or
four indistinct rings, and is simply membranous.

The stem and branches are closely and regularly annu-
lated throughout.

The capsules present no peculiarity ; they form a very

42 COIIYNLCLE.

dense mass over about two-thirds of the body of the polypite.
The ova are large, and have a conspicuous germinal vesicle.
Mr. Gosse witnessed the exclusion of 25 from a single
capsule, " the process being all over in about a minute."
The number varies considerably : I have met with 12, 18,
and 20. They are oval or circular, and of a brownish
colour, but undergo remarkable changes of form after ex-
clusion, shooting out processes here and there, and hardly
presenting the same shape for many seconds together.
They seem to have no locomotive power*.

This beautiful species is identical with the Coryne
figured by Lister in his notable paper in the Philosophical
Transactions for 1834. Gossc has also given a very
characteristic representation of it. The Syncoryna Listerii
of Van Beneden is certainly not identical with Lister's
species.

Hob. In tide-pools, near low-water mark : South Devon:
Ilfracombe, and neighbouring coast : Swanage, Dorset :
Clew Bay, co. Galway (T.H.) : co. Cork, common (G. J.A.) :
Channel Islands, very fine.

This is the common Coryne along the south-western
coast. Its favourite habitat is amongst the luxuriant
vegetation clothing the sides of the tide-pools, where it
attains a large size, and adds not a little to the beauty of
their scenery.

3. C. VERMICULARIS, Hilicks.
" On New British Hydroida," Ann. N. II. for October 1806.

Plate VIII. fig. 2.
ZOOPHYTE /ow/m/gr dense shrubby tufts ; STEM much branched

* Mr. Gosse has recorded similar observations in his ' Devonshire Coast.'
pp. 194-195.

CORYNE VEKMICULAllIS. 'io

dichotomously , of a very light straw-colour and delicate
texture, wavy, annulated, especially towards the base,
the branches and upper portions of the stem often
smooth or slightly wrinkled ; POLYPITES of great length
(about ^ inch when mature), stout, almost cylindrical
for half their length when extended, then tapering off
very gradually towards the oral extremity ; tentacles in
irregular and very distant ivhorls, rather stout, with
large capitula, about 25 in number.

GONOPHORES borne at the base of the tentacles over the
lower half of the body, spherical, shortly stalked.

Height of the tufts about | inch.

THE size of the polypites is the point that first attracts
attention in this species. The length is remarkable, being
about a third greater than in any other British Coryne.
The body is thick, and cylindrical below, and tapers off
very gradually towards the apex. Altogether the polypites
have a very worm-like appearance. The tentacles are
sparingly distributed over the surface, a considerable space
intervening between the imperfect whorls over the whole
of the upper portion of the body. They are more nume-
rous and closely set near the base.

The polypary is exceedingly delicate, being colourless
and perfectly transparent on the branches, where the
ringing is often very faint or obsolete. The cocnosarc is
of great thickness, almost filling up the tubular cavity of
the stem. The branches are short and wavy. The rami-
fication commences near the base of the primary stem,
and consists of a succession of dichotomous divisions and
subdivisions, resulting in the formation of little slirub-like
tufts. Many filamentous branchlets, not bearing polypites
and slightly clavate at the extremity, are distributed over
the zoophyte (Plate VIII. fig. 2, x x}. The reproduc-
tive buds seem to be confined to about the lower third of
the body.

44

CORYNID^l.

In many of the polypites the anterior
portion of the body is much swollen and
destitute of tentacles, a change which is
probably due to the presence of some
parasitic larva. [Woodcut, fig. 3.]

I have not had the opportunity of ex-
amining C. vermicularis in a living state.
The foregoing description is founded on
numerous specimens, well preserved in
spirit, which were supplied by Mr. Busk.

Hob. Shetland, from deep water.

Fig. 3.

4. C. FRUTICOSA, Hincks.

"Catalogue of Devon and Cornwall Zoophytes," Ann. N. H. (3rd ser.) viii.
158-9, pi. vi. figs. 5, 6.

Plate VII. fig. 2.

ZOOPHYTE bushy ; STEM slender, slightly and irregularly
annulated throughout, much branched ; polypary delicate
and light-coloured; BRANCHES erect, long, closely set,
much and irregularly ramified; POLYPITES somewhat
swollen beloiv, tapering above, with about 20 tentacula,
which are rather long and furnished with small capitula,
a verticil of five immediately below the mouth, and the
rest scattered.

GONOPHORES densely clustered, chiefly about the lower part
of the body, sessile.

Height from an inch to an inch and a half.

THIS species forms dense, clustered, bushy masses on
Fucus ; it is of very delicate habit. The polypary, which
is extremely thin and transparent, is more or less ringed
throughout, but the annulations are neither regular nor
strongly marked. The branches grow erect, and attain a

CORYNE VAN-BENEDENII. 45

considerable length, those which spring from the lower
part of the stein often rising to the height of the main
shoot ; they are set closely together, and give off' plenti-
fully secondary branches and branch lets. The polypites
are of moderate size ; they are somewhat enlarged below,
and taper gradually towards the oral extremity. They
want the narrow neck that supports those of C. vayinata,
and there is no membranous cup at the base. The ten-
tacles are rather long and slender, and have very small
tips. The reproductive sacs, when mature, are very large ;
they often form a kind of collar round the lower part of
the body, but are sometimes more diffused. The dense
bushy growth of C. fruticosa is very unlike that of any
other British species.

Hub. On Facus, Mount's Bay : Exmouth (T. H.) : Herm
(half-tide), forming luxuriant tufts 011 a seaweed (G.
Hodge) .

5. C. VANBENEDENII.

SYNCORYNA PUSILLA, Van Brn(den, Rech. sur les Tubul. f>2, pi. iii. figs. 1-10.
CORYNE PUSILLA, Johnst, B. Z. 41, pi. iv. figs. 1, '2.

Plate IX. fig. 1.

ZOOPHYTE small and very delicate ; STEM flexuous, irregu-
larly branched, bearing many short, non-poly piferous
ramules ; polypary transparent, papyraceous, pale yellow,
ivith a few obscure wrinkles ; POLYPITES small, subclavate,
with a slight membranous cup round the base ; tentacles
from 12-16, or sometimes more; GONOPHORES few in num-
ber (2—3), very large, pedunculate, situated at the base
of the lower tentacles ; EMBRYO actiniform.

Height from ^ to f inch.

WE are mainly indebted to Van Beneden for our know-

CORYNHLE.

ledge of this species, which he has described under the
name of Syncoryna pusiUa. It has no claim, however,
to be identified with the original C. pusUIa of Gaertner,
and I have therefore renamed it after its distinguished
discoverer.

Van Beneden describes the tentacles as disposed in
three equidistant rows of four each, but remarks that he
had seen individuals with only two rows, and that iu other
cases it was difficult to recognize any regularity in their
disposition. The number of arms is dependent on age,
and in adult polypites reaches 16 or even more. There
is a very slight tendency to verticillate arrangement.

The stems are extremely delicate and irregularly flexu-
ous, and the polypary is thin and transparent. The num-
ber of short ramuli not bearing polypites is a marked
character.

The polypites are somewhat clavate in form, blunt, and
rounded at the oral extremity, and tapering off slightly
below, but not produced as in Syncoryne Sarsii. There
is a small membranous dilatation of the polypary round
their base.

Van Beneden has given us an account of the mode of
reproduction. The embryo is actiniform, and on issuing
from the reproductive sac resembles a miniature Octopus,

Fig. 4.

with four arms (fig. 4). It moves sloAvly about for a

CORYNE VAN-BENEDENII. 47

time by means of its rudimentary tentacles, and at last
fixes itself by tlie base and assumes the perfect form.

Through the kindness of the late Mr. Alder I have had
the opportunity of examining specimens supplied by Van
Beneden himself, and found at Ostend, and I am thus
enabled to describe some of the earlier stages of de-
velopment.

The gonosacs are capacious and contain a single em-
bryo, which occupies the centre of the cavity.

The oral extremity is uppermost ; and four rudimentary
tentacles can be distinguished through the walls of the
sac, in mature specimens, surrounding a prominent pro-
boscis. Four simple tubular processes, taking their origin
in opposite pairs at the base of the gonosac, embrace the
embryo, and converge above it (Plate IX. fig. 1 c}. They
are the representatives of the gastrovascular canals.

We have in this case a mode of reproduction very
similar to that which is met with in the genus Tubnlaria.

I am unable to give any British habitat for C. Van-
Benedenii. It has never occurred to myself, nor have
I received it from any of my correspondents. Dr.
Johnston, however, has given an original and very
characteristic figure of it, which was taken from British
examples, and he states that it is often parasitical on
Tubularia indivisa.

The Syncoryna pusiHa of Van Bencdcn's latest work*
is a different species, and referable to the next genus.

* Reclierchos sur la Faunc Littoralc deBclgique, Pott/jifx, 1S(>0. \i. 11',).

48

Genus SYNCORYNE, Ehrenberg (in part).

Der. <rvv, along with, and Coryne, a genus of Hyclroicls.
[Tlie synonymy given for the last genus applies equally to this.]

SARSIA (the free zooid), Lesson, Zooph. Acaleph. 333.
STIIENYO (ditto), Dujardin, Ann. Sc. Nat. (1845).
SYNCORYNE, Allman, Ann. N. H. for May 1864.

GENERIC CHARACTER. — Stem simple or branched, rooted
by a creeping filiform stolon, the whole sheathed in a thin
chitinous tube, smooth or cumulated ; polypites terminal,
more or less clavate ; tentacles capitate, scattered over the
body ; gonophores borne on the body of the polypite, and
containing medusiform zooids.

Gonosooid : Umbrella (at the time of liberation] deep
bell-shaped or globular; manubrium not reaching to the
orifice of the bell, with a simple mouth ; radiating canals
4; marginal tentacles 4, springing from ocellated bulbs.
The mature zooid has the manubrium enormously developed.

SYNCORYNE embraces the members of the old genus
Coryne that originate free reproductive zooids of the
Sarsia type. I follow Allman in adopting for this sec-
tion Ehrenberg' s name, which has been widely used,
especially amongst continental naturalists.

There are several points of special interest in the re-
productive history of this genus. In the first place, the
free zooids of the British species are either identical,
or nearly so, at the time of their liberation from the
parent stock. The differences, where any exist, are very
slight. In one case (S. gravata] the umbrella is desti-
tute of thread-cells, which are present in all (?) the other
species. S. pulchella has two interradial furrows on the
bell, and S. gravata and S. decipiens four. In S. eximia

SYNCORYNE. 49

and S. Sarsii no furrows have been observed. The gono-
zooids of these two species, and of the Stauridium pro-
ductum, seem to be perfectly similar in all external cha-
racters, at least in the first period of their free existence.
Observations are still wanting to show whether differences
arise in the further course of their development.

The researches of Agassiz have proved that the free
zooid of S. gravata (C. mirabilis, Agass.) assumes, when
mature, the form of Sarsia, a genus founded by Lesson
for a " Naked-eyed Medusa," whose most striking charac-
teristic is thf remarkable length and extensibility of the
manubrium. It was discovered bv the distinguished

v

Norwegian naturalist whose name it bears.

The changes which the zooid of S. gravata undergoes
in its progress towards maturity seem to be almost con-
fined to the manubrium. There is a slight alteration in
the shape of the umbrella, but no increase in the number
of tentacles with age. The manubrium in the adult
state, when extended, is twice or three times the length
of the umbrella. The upper portion, by which it is sus-
pended from the centre of the crystal dome, is thinner
than the rest ; the middle region is somewhat inflated (and
it is here that the ova are developed), whilst towards the
free extremity it is more or less clavate in form [Plate
III. fig. 3]. At the time of liberation, the manubrium
is of moderate dimensions, and does not extend to the
mouth of the bell. It is probable that in all the species
of Syncoryne the free zooid passes through a similar
change.

We are also indebted to Agassiz for the interesting-
observation that the gonozooid in some cases presents a
very different appearance in the early and latter part of
the breeding-season. In the one it is free and perfectly
developed; in the other it is sometimes reduced to a fixed

50 CORYNID.E.

condition, its shape is altered, the tentacles are wanting,
and the generative products are matured while it is at-
tached to the zoophyte. In such cases the polypites
also are often atrophied. One or two species have been
founded on this merely seasonal phase.

The species of Syncoryne are for the most part littoral,
and seem to be very indifferent to the quality of the water
in which they live. S. gravata, according to Agassiz, is
found either in pure sea-water or at the mouths of rivers ;
and Loveii states that S. Sarsii occurs even in stagnant
water.

1. S. EXIMIA, Allman.

CORYNE EXIMIA, Allman, Ann. N. H. for August 1859.

„ LISTERII, Alder, North. Cat. in Trans. Tynes. Club, iii. 102.
SYNCORYNE EXIMIA, Allman, Ann. N. H. for May 1864.

Plate IX. fig. 2.

ZOOPHYTE forming large entangled masses, much and ir-
regularly branched ; MAIN STEMS smooth, except towards
the base ; BRANCHES generally ringed above their origin,
bearing polypiferous ramuli, which are mostly unilateral
and annulated throughout ; POLYPITES rather small, with
a membranous cup round the base ; tentacles from 20
to 30, scattered over the body, with the exception of
the first 4, which are disposed in a verticil behind
the mouth; GONOPHORES pedunculate, springing from
the bases of the tentacles over the greater part of t/te
body.

UMBRELLA of the free zooid (at the time of liberation)
deeply bell-shaped, studded with thread-cells of large
size (about 0-06" in transverse and a little more in ver-
tical diameter), with a wide velum; MANUBHIUM reddish,
extending to about the middle of the umbrella; MAR-
GINAL TENTACLES very extensile, springing from large

SYNCOIIYNE EXIMIA. 51

red bulbs, with a dark reddish-brown ocellus on the
outer side, and set with knot-like clusters of thread -
cells, the terminal group forming a spherical bulb.
Height of the stems 3 or 4 inches in fine examples.

S. ExmiA has small reddish polypites, with an opake-
white proboscis, and a very delicate membranous cup
round the base.

The general colour of the zoophyte is a pale pink.
The reproductive buds are mounted on long peduncles,
and are developed in large numbers over almost the whole
of the body.

The smoothness of the principal stems and the uni-
lateral arrangement of the branchlets are characteristic
points.

S. eximia is one of the Hydroids that are infested by
the larvse of the Pycnoyon, a very curious form of Crusta-
cean *. The parasitism is of a most extraordinary kind.
At a very early stage of their existence the young Pycno-
ffons gain access in some way or other to the interior of
the Zoophyte, and find their way through the cavity of
the coenosarc into the budding polypites, which they oc-
cupy, using them as nests during the further stages of
their development.

The growth of the nascent polypites thus invaded is
arrested, and they are converted into long clavate sacs,
within which the larval intruders find an undisturbed
retreat. At the proper time they rupture the investing
polypary, and make their exit.

On a small colony of the Syncoryne I have found as many
as five of the Pycnogon sacs. They were of a rose-red
colour ; and from one of them the young Crustacean was
extricating itself, one or two legs protruding at the top.

* Vide a paper by Mr. Geo. Hodgo, Ann. X. H. (ser. 3) vol. ix. p. .'fci.

E 2

52 COBYNIDJE.

Hab. Attached to rocks and the stems of Laminaria
digitata, Firtli of Forth (G. J. A.) : on Coral/inn and other
seaweeds, and on the sides of rock-pools, Northumberland,
very abundant (J. A.) : Seaham Harbour, abundant (G.
Hodge) : Hartlepool (A. M. N.) : Whitby : Filey Brigg, on
Laminaria and other weeds, towards low-water mark,
very abundant (T. H.).

This is the common Syncoryne along the north-eastern
coast.

2. S. SARSII, Loven.

SYNCORYNA SARSII, Loven, Svenske Vetensk. Acad. ITancll. 1835, tab. viii.
figs. 7-10; Wiegmann's Archiv, 1837, 321, tab. vi. figs. •_'.'»
28 ; Sars, Faun. Litt. Norv. part i. 2, t. i. figs. 1-G.

,, RAMOSA, Loven, loc. cif. tab. viii. figs. 1-6.

,, LOVENII, Sars, Faun. Litt. Norv. part i. 2 (footnote).

Plate VII. fig. .",.

STEM slender, very sparingly branched; polypary trans-
parent, of a very light horn-colour, sliylitlij and irregu-
larly wrinkled or annulated, especially towards the base,
generally smooth above; POLYPITES elongate oval, of a
light red colour, produced below into a long neck, with
12-16 tentacles scattered over the body; GONOPHORES
(2 or 3) with short peduncles, borne chiefly, but not
exclusively, at the base of the lowest tentacles.

UMBRELLA of the free zooid (at the time of detachment)
globular, with thread-cells; MANUBRIUM short; MAR-
GINAL TENTACLES springing from bulbs, each bearing a
reddish-brown ocellus, nodulated with thread-cells, and
terminating in a spherical cluster.

Height of zoophyte about i inch.

THE stems of S. Sarsii, which are very slender, and not
flexuous and tangled as in Coryne VanBenedenii, are either
simple or bear two or three short branches. There is very

SYNCORYNE GRAVATA. 53

little distinct ammlatioii on the polypary, but towards
the base there is always a certain amount of rather
irregular ringing, and here and there it is more or less
strongly wrinkled. The upper part is generally smooth.
The polypite is ovate above, and produced below. The
polypary only extends to the base of a long neck, on which
the tentaculiferous portion of the body is supported. The
line of junction is very distinctly marked.

The erect and comparatively simple habit, the annulatcd
stem, and the form of the polypite distinguish this species
from the C. VanBenedenii. It is also of larger size.

As Agassiz has suggested, the Syncoryna ramosa (Loven)
(S. Lovcnii, Sars*) is probably only the phase assumed
by the S. Sarsii towards the close of the breeding-season.

Hub. Firth of Forth (T. S. W.) : Seaham Harbour,
Durham, on Antennularia, from 25 to 30 fath. (G. Hodge) .

[The Cattcgat (Loveii) : Island of Floroe (Sars) .]

3. S. GRAVATA, T. S. Wright,

CORYXE GRAVATA, Wright, Observat. on Br. Zooph. Ed. New Phil. Journ. for

April 1858, pi. vii. fig. 5.
S utsiA .MIRABILIS (the sexual zooid), Agassi;, Mem. Ainer. Acad. of Arts and

Sciences (I860), iv. part ii. 224, pi. 4. 5.

CORYNE SUHABILIS, Agassiz, N. H. U. S. iv. 185, pi. xvii. (vol. iii.).
TUBULARIA STELLIFERA, Couth. Boston Jouru. N. H. ii. 56.

Plate X. fig. 1.

STEM smooth, simple or slightly branched; POLYPITES
small, slender, with 16 tentacles in the adult state;

* The Syneoryna Loven ii of Van Bciieden ( Kecli. isur la Faune Litt. de Bel-
gique, p. 121, pi. v. figs. 6, 7) is a totally distinct species ; it.s polypites are
of great length, and have many whorls of tentacles. It may be our ('m-i/m-
•pusilla, but I confess myself unable to identify with certainly any of tin'
species of Syncoryne described in the above work.

54 CORYNIDzE.

GONOPHORES somewhat globular, borne amongst the
tentacles, or immediately below them.
GONOZOOID. — UMBRELLA (at the time of liberation) globular,
destitute of thread-cells, with 4 interradial furrows;
MANUBRIUM extending to about the middle of the um-
brella, subcylindrical ; MARGINAL TENTACLES springing
from bulbous bases, bearing a prominent dark ocellus,
nodulated with clusters of thread-cells, and terminating
in a spherule.

THIS species is the subject of an elaborate memoir by
Agassiz, in which he has treated its history exhaustively.
He has also fully described the adult gonozooid in a sepa-
rate paper. Wright had previously discovered the species
in Scotland, but had only met with it in the depauperated
condition which, according to Agassiz's observations, it
assumes towards the close of the breeding-season. He
describes his Coryne mirabilis as producing in the early
part of the year free gonozooids that resemble the Sarsia
of authors, while later on (April or May) these disappear,
and their place is taken by medusiform bodies of a differ-
ent shape, which probably in most cases continue fixed,
and mature their generative elements in situ. And this
change in the reproductive zooid is usually accompanied
by the degeneration and sometimes total disappearance
of the polypites. In this stage of the life-history, the
gonozooids are imperfectly developed. They are elongate-
ovate or cylindrical in form, generally with four small
bulbs instead of tentacles, and a manubrium inflated by
the mass of ova or spermatozoa, so as almost to fill the
cavity of the bell. Occasionally the tentacles are developed,
but " they have a stiff, jagged, and awkward appearance."
Some of these abnormal zooids have " a withered arid
wrinkled look," and probably cast their products in situ
and then perish. Others exhibit vigorous movements, and

SYNCORYNE GRAY ATA. 55

may, Agassiz conjectures, drop from the parent stem,
though he has never found them swimming freely like the
perfect zooid. At the same time the polypites are often
more or less affected. The tentacles are sometimes reduced
by absorption to mere papillae ; sometimes they disappear
altogether; and in some cases the whole head vanishes,
and the stem is surmounted by a single gonozooid, or
occasionally by two.

In the month of May I found a large colony in the
latter condition, overspreading the underside of a stone on
Filey Brigg. The heads of the polypites had in almost all
cases disappeared, and each stalk bore near its extremity
one or two ovate medusiform bodies attached by a short
peduncle (Plate X. fig. 1 d) . The tentacles were represented
by mere projections on the margin of the umbrella, on
each of which there was a dark spot. The maimbrium
was rose-coloured and not inflated. The zooids were ac-
tive in their movements.

I have no doubt that the C. gravata of Wright is iden-
tical with the C. mirabilis of the American coasts ; and his
name, as the first published, must take precedence.

Agassiz has established the identity of the free zooids
produced by his Coryne mirabilis with a Sarsia (of authors)
which abounds in Boston Harbour during the spring
months (March, April, and May) . The ice has scarcely
gone from the shores, we are told, when it makes its ap-
pearance in numbers, that " swarm near the surface on
any sunny day " *. The adult zooid seems to resemble
very closely the Oceania (Sarsia} tubulosa of Sars, figured
in the ' Beskrivelser/ and may probably be identical with
it. It is described as very active and graceful in its move-
ments, and very voracious, swallowing quickly " large
numbers of small Medusae and, especially, other kinds of
* ' North American Acalephae,' by Alexander Agassiz, 176.

56 CORYNID^E.

Hydroid Medusae and the young of Aurelia flavidula, and
also other soft animals and small Crustacea/3 Forbes has
celebrated the appetite of Sarsia tubulosa for Crustacean
diet, and tells us how it apparently enjoys " the destruction
of the unfortunate members of the upper classes with a
truly democratic relish. "

The maiiubrium is capable of extraordinary elongation,
and is a formidable instrument for the capture of prey.
When contracted, it is not more than half the length of
the bell.

S. gravata is of humble size and very slightly branched.
The stems are often perfectly simple, and only about a
quarter of an inch in height. Dr. Wright describes the
polypites as colourless; but Agassiz says that the zoophyte is
tinted rose by coloured granules lining " the whole extent
of the digestive cavity and chymiferous tube." Possibly
the absence of distinct colour may have been due to the
depauperated condition of the specimens examined by the
former of these observers.

Hab. North Berwick, spreading over the surface of
stones in a rock-pool (T. S. W.); Filey Brigg, Yorkshire,
in a similar situation (T. H.). I have also taken the form
known as Sarsia tubulosa at the same place.

[North America (Agassiz) .]

4. S. DECIPIENS, Dujardin.

SVNCOKVXA DECii'iE.NS, Dujardin, Ann. Sc. Nat. (3rd ser.) Zool. vol iv. 275,
pl.xiv.

I 'Lie X. fig. 2.

STEM smooth, slightly branched; POLYPITES slender, red-
dish, someivhat fusiform, with a prominent proboscis and
much produced below : teittactf/a 8 or 9, scattered over

SYNCORYNE PULCHELLA. 57

the thickest portion of the body; GONOPHORES pyri-
form, reddish, on short peduncles, borne behind the
lowest tentacles.

UMBRELLA of the free zooid bell-shaped, the height and
width about equal, with four interradial furrows* ; MA-
NUBHIUM lageniform ; MARGINAL TENTACLES springing
from bulbous bases, each with a dark ocellus, nodulated
with thread-cells, and terminating in a larger spherical
cluster.

THIS species is nearly related to the preceding. The small
number of tentacles is one of the chief distinctive cha-
racters. The gonophores also, apparently, are not scattered
amongst the tentacles as in S. gravata, but are borne
behind the lowest.

I have not had the opportunity of examining specimens ;
but Mr. Alder's drawing from which our figure is taken,
and which may be trusted for its accuracy, shows that the
form of the polypite is peculiar. The oral extremity is
elongated and narrowed ; immediately below it the body
swells out for a short distance, and then tapers off gra-
dually towards the base. The tentacles, which are rather
long and slender, are distributed over the thicker portion
of the body.

The species requires further investigation.

Hab. Firth of Forth (T. S. W.).

5. S. PULCHELLA, Allmau.

"Notes on the Hydroida,'' Annals N. H. for June 1865.

STEMS unbranched and attaining a height of about half an
inch, not annulated, but with a few shallow transverse
corrugations towards the base, of an orange colour ; POLY-

* "An milieu de 1'intervalle des canaux se trouvc un sillon qui parait occupe
par nil cordon tendinous, duquel partent des fibres contractiles." — Dujardin.

58 COKYNID^E.

PITES with 15-20 tentacula, body deep orange, becoming
pale where it passes into the stem ; GONOPHORES borne
on short peduncles in a dense cluster immediately behind
the lowest tentacles.

GONOZOOID. — UMBRELLA bell-shaped, with its transverse
and vertical diameters nearly equal, covered with thread-
cells, and traversed by two opposite interradial furrows,
extending from the base of the manubrium to the margin
of the bell; MANUBRIUM deep orange; MARGINAL TEN-
TACLES springing from orange bulbs, with a distinct
ocellus, nodulated with clusters of thread-cells, and
with a larger spherule at the extremity.

CLOSELY allied to S. decipiens, from which it differs " in
its simple habit, in the more ovate form of the polypite,
and in its more numerous tentacles" (Allman). The um-
brella also has only two of the furrows, instead of four as
in Dujardin's species.

Hub. Rooted to the bottom of rock-pools near low-water
mark. Skelmorlie, Firth of Clyde (G. J. A.) .

Genus ZANCLEA, Gegenbaur *.

GEMMARIA, M'Cracly, Gymnophthalmataof Charleston Harbour, Proc. Elliott
Soc. Nat. Hist. Charleston, 151.

GENERIC CHARACTER. — Stem simple or branched, rooted
by a creeping filiform stolon, the whole invested by a chitin-
ous polypary ; polypites more or less clavate ; tentacles capi-
tate, scattered over the body ; gonophores borne on the body
of the polypite, and originating free medusiform zooids.

Umbrella of the sexual zooid (at the time of liberation]
nearly spherical; manubrium not reaching the margin of
the bell, tvith a simple mouth ; radiating canals 4 ; marginal

* "Versuch eines Systemes cler Medmen,'1 in Zeitschrift fur wissenschaft-
liche Zool. 1856, p. 229, t, viii. fig. 4.

ZANCLEA IMPLEXA. 59

tentacles 2, set along one side with pedunculated sacs, filled
with thread-cells, and springing from non-ocellated bulbs at
the extremities of opposite canals — the two intermediate
canals terminating in bulbous dilatations, without tentacles ;
a caecal tube filled with thread-cells extending, in the walls
of the umbrella, from the bases of the 4 tentacular bulbs,
and parallel to the corresponding radiating canal*.

ACCORDING to Gegenbaur's observations, the free zooid
of Zanclea has four tentacles when adult. The manubrium
does not change with age, as in that of Syncoryne, but
continues short up to the time of the development of the

ovaf-

The characters on which the Gemmaria of M'Crady is
founded seem to be quite insufficient to justify its separa-
tion from Zanclea, if unaccompanied by important differ-
ences iu the trophosome. A. Agassiz believes that the
polypites of the two forms are most closely allied ; if so,
I can see no ground for retaining M'Crady's genus.

Z. IMPLEXA, Alder.

TUBULABIA IMPLEXA, Alder, Trans. Tynes. Club, iii. 108, t. ix. figs. 3-0.
COUYNE PELAGICA, Alder, ibid. iii. 103, t. ix. figs. 1, 2 (the young).

,, IMPLEXA, Aider, ibid. v. 227-

„ BRIAREUS, All-man, Ann. N. II. (July 1859), 3rd ser. iv. 54.
ZANCLEA IMPLEXA, Allman, Ann. N. H. for May 1864.

Plate IX. fig. 3.
STEM slender, slightly and subunilaterally branched, from

* Of these groups of thread-cells M'Crady says (Gymnophthalmata of
Charleston Harbour) that their " refractive power gives them a brilliancy
such as to remind us irresistibly of clusters of precious stones. These bril-
liants are set in a membranous case."

t Vide Gegenbaur's figure, tab. viii. f. 4 i.

60 CORYNLD/E.

£ to | inch high ; POLYPARY composed of two coats, the
inner horn//, more or less cumulated, the outer membranous,
smooth, transparent ; POLYPITES* nearly cylindrical, much
elongated, very transparent, of a pearly white colour ;
tentacles numerous (40-50), very small and slender, set
in 7 or 8 imperfect rows ; GONOPHORES in a single sub-
verticillate cluster towards the lower part of the body,
shortly stalked.

GONOZOOID with a nearly spherical UMBRELLA (at the time
of liberation) and a wide velum ; MANUBRIUM subcylin-
drical, carmine-coloured ; MARGINAL TENTACLES springing
from reddish tubercles.

THIS species is one of the most beautiful of its tribe, and
is at once distinguished by the peculiar structure of its
polypary, the long subcylindrical body, and the very large
number and remarkably small size of the tentacles. It
sometimes forms dense tangled masses, but is not uncom-
monly found of much humbler size and simpler growth.

Dr. Wright has described the thread-cells, which are of
two kinds — oval and barbed on the tentacles, and long
and cylindrical on the body of the polypite. Both are
present within the polypary.

We have an interesting observation by Allman on the
structure of the tentacles of the gonozooid*. He found
the peduncles of the sacs containing thread-cells (which
are set along the whole length of the arms) to be capable
of enormous elongation. They have the power of ex-
tending themselves to a length which considerably sur-
passes that of the longer or vertical diameter of the um-
brella. ' ' While the medusa continued to float undisturbed
through the water, the peduncle would remain projected
in a straight line, becoming at the same time amazingly
attenuated ; but on the least disturbance it would become

* " Notes on the Ilyclroicla," Ann. N H. for July 1864.

STAURIDIID^E. 01

suddenly shortened to less than the one-twentieth part
of its length when extended, drawing the capsule back
with it in its contraction /J

A pencil of long fine vibratile cilia surmounts each
capsule, and keeps it, when the peduncle is extended, in a
state of constant movement.

Hub. On an old anchor from 40 fathoms, 30 miles east
of Holy Island, coast of Northumberland (R. Howse) : on
shells of Fusus antiquus from deep water, Cullercoats (J.
A.) : on Cellepora pumicosa, Seaham Harbour (G. Hodge) :
Inch Garvie (T. S. W.) : on stone in a rock-pool, Firth of
Forth (G. J. A.).

Family VI. — Stauridiidss.

POLY FIXES clavate or subcylindrical, ivith true and J\ilsc
tentacula, the former capitate, and disposed in one or
more verticils ; the hitter rigid, without capitula, and
probably serving as tactile organs.

Genus CLADONEMA, Dujard'm.

Der. K\acvos, a branch, ;incl I'ijpa, a thread (tentacle).

GENERIC CHARACTER. — Steins s'unple or branched, rooteil
by a creeping filiform stolon, the ivhole invested by a poly-
par y ; polypites borne on the summit of the stems and
branches, clavate, with a single verticil of four capitate
tentacula placed immediately below the oral extremity, and
disposed in the form of a cross, and beneath these four
false tentacles or tactile organs, also arranged in a cross,

02 STAURIDIID^E.

rigid, destitute of capitula, covered towards the extremity
with palpocils ; gonophores borne on the body of the poly-
pite, and originating free medusiform zooids.

Gonozooid. — Umbrella deep bell-shaped; manubrium large,
with a number of tubercles round the mouth; radiating
canals 8-10 ; marginal tentacles springing from ucellated
bulbs at the extremity of the canals, branched, nodulated
with clusters of thread-cells, and furnished towards the base
ivith appendages bearing suctorial disks.

ALLMAN ranks Cladonema and Stauridium in the family
of the Pennariidce ; but their affinity, as it seems to me,
is clearly with the Corynidc? and Clavatellidae, while Pen-
naria is closely allied to Tubular ia. The curious append-
ages which I have named false tentacles can hardly be
compared with the wreath of inferior tentacles in the
latter genus ; they are members of the same system to
which the capitate arms belong, modified, and discharging
a different function.

C. RADIATUM, Dujardin.

CLADONEMA RADIATUM (free zooid), Dujardin, Ann. des Sc. Nat. xx. (1843)
370; Ann. des Sc. Nat. (3rd ser.) Zool. iv. 271.

CORYNE STAURIDIA ("the slender Coryne"), Gosse, Dev. Coast, 257, pi. xvi.
figs. 1-5.

Plate XI.

STEM simple or slightly branched, of extreme tenuity ;
polypary perfectly hyaline and smooth ; POLYPJTES cla-
vate, rounded at the oral extremity, tapering off below
(when extended) to about the thickness of the stem,
coarsely annulated ; the eiidoderm laden with opake-
white granules ; the four capitate tentacula covered
with small tubercles, bearing palpocils ; the four false

CLADONEMA RADIATUM. 63

tentacles placed a little above the termination of the
body and at right angles to it, rounded at the tip ;
GONOPHORES large, two or three in number, developed
at the base of the inferior tentacles.

GONOZOOID. — UMBRELLA deep bell-shaped, covered with
minute thread-cells, slightly produced and pointed at
the top, immediately over the base of the manubrium ;
MANUBRIUM fusiform, lobed, with 5-7 oral tubercles ;
MARGINAL TENTACLES springing from red bulbs, each
with a dark ocellus, more or less branched, very exten-
sile, roughened by prominent groups of thread-cells,
and furnished with a variable number (1-4) of filiform
appendages, terminating in suctorial disks.

DUJARDIN was the first to describe this very curious and
beautiful Hydroid. He has given a full account, accom-
panied by admirable figures, of its structure and develop-
ment. It has also been studied by Krohu, Gegenbaur,
and Van Benedeu. Gosse has described the polypites
from Devonshire specimens, but did not meet with the
reproductive bodies.

My friend Mr. E. W. H. Holdsworth has been fortunate
enough to procure several specimens of the free zooid from
the tanks in the Zoological Gardens, and has succeeded
in keeping them, so as to trace almost the entire course
of the reproductive history, while his own aquarium has
yielded the polypites in considerable numbers. His notes
and sketches he has very kindly placed at my disposal ;
and they enable me to supply an original account of the
species, which corroborates, and in one or two points
corrects, that which we have from Dujardm.

The polypites are very mutable in form, as the accom-
panying woodcuts, which are careful studies from nature,
will show (fig. 5). Fig. /represents an individual that has
swallowed a Cyclops, whose tail protrudes from the mouth.

STAURIDIIDJE.

"All the motion/' Mr. Holds worth remarks, "takes
place above the lower arms, which always appear to retain

Fig. 5.

their position at right angles to the lower part of the
body." The apparatus for the capture of food is very
complete. The spherical bulb at the extremity of the
upper tentacles is a congeries of thread-cells, each of
which furnishes its projectile; the arm itself is endowed
with vigorous percussive power, and its surface is studded
with minute tubercles surmounted by sensitive palpo-
cils. The false tentacles are rounded at the tip, which is
thickly covered with the tactile hairs ; and their function
seems to be to give notice of the presence of animalcules
or other prey. If anything touches one of them, the head
and upper arms are instantly bent towards it.

The specimens of the gonozooid examined by Mr. Holds-

CLADONEMA 11ADIATUM. 65

worth differed from Dujardiir's in having ten arms instead
of eight, and seven oral lobes instead of five. The number
of branches on the arms is variable. In some cases there
is only one, in others two or three are present. Probably
the number increases with age. The suctorial appendages
also vary in number. ' ' Most commonly there are three,
rarely only one, more frequently two, and sometimes four/'
They are attached to the tentacles just above the basal
enlargement, and, unlike the same organs in Clavatella
prolifera, are never used for locomotion. The zooid fre-
quently fixes itself firmly by means of its suckers, and the
arms are thrown back (" redresses ") , and stand erect
around the umbrella*. It swims by short and rapid
jerks; and when in motion, the tentacles are closely
retracted and the suckers outstretched.

The lobes which surround the mouth are pedunculatcd
clusters of thread-cells, and arc identical in structure with
the capitula of the tentacles.

The later stages in the history of the zooid have been
carefully observed by Mr. Holdsworth ; and his account of
them agrees in the main with Dujardin's. After a time
the umbrella begins to slough away at the top, and the
subumbrella is much depressed, so that the manubrium is
protruded through the orifice in the velum. At this stage
the zooid is firmly attached by its suckers, and the arms are
in frequent motion.

The sloughing away continues until there is nothing
left but the manubrium " with the subumbrella flattened

* " Eieri n'est gracieux comme un Cladoneme nonchalamment etale au
milieu cle son bassin, fuyant devant quelque danger imnginaire ou reel, on
solidement tapi par ses ventouses pour resister au courant, pendant qu'il
etale soigneusement ses longs cirrhes dans toutes les directions. On pent
rester des heures entieres en contemplation dovant ces organismes infimes,
qui semblent moins solides qu'une bulle dp savon, et qui se conservent
cependant en depit des vagues. des chocs et des tempetes." — Vim £e»cdcn.

F

66 STAURIDIID^.

down and gathered together at its base, the tentacles being-
still perfect and forming a fringe at the rear of the base."
They are as active in contraction and extension as when
the umbrella was perfect. This change occupied, in the
case described by Mr. Holdsworth, from the 19th to the
22nd of August. The reproductive zooid had now dis-
carded the accessory structure essential to a free existence,
and returned to the simple polypite condition.

On the 1st of September, eight of the ten arms had
become detached and were leading an independent life.
They survived in this state for several days, moving about
bodily to a slight extent.

On the 6th of September the manubrium was observed
to raise itself and stand erect, " and whilst doing so the
mouth expanded and the margin was slowly turned back
until it almost reached the base ; and at the same time a
cloud of minute specks was expelled. After about two
minutes the manubrium resumed its natural shape; but ova
continued to pass out, singly or a few at a time." The
margin was afterwards thrown back on several occasions,
whilst the manubrium was still on its side and ova dis-
charged more or less abundantly. Dujardin describes
some of the eggs as being deposited before the disappear-
ance of the umbrella, and tells us that they were removed
from the stomach by the tentacles and glued to the sides
of the vessel in which the zooid was kept. Nothing of the
kind has occurred to Mr. Holds worth, and he is inclined
to regard the somewhat marvellous story as founded 011 a
mistake. "When the animal was perfect/' he writes,
" one or two tentacles were frequently inserted far into the
peduncle ; but this was simply conveying food to the
stomach, as I have often distinctly observed. I have
watched an animalcule accidentally touch one of the ten-
tacular branches, and instantaneously it, with the greater

STAURIDIUM. 67

part of the entire tentacle, has been thrust far into the
throat. I cannot help thinking this may have been mis-
understood, and possibly some minute and irregular projec-
tions (which exist on the tentacles besides the regular masses
of thread-cells) may have been mistaken, on the tentacle's
return, for ova." He adds that the arms are often applied
to the glass. I have little doubt that this is the true
explanation of the appearances on which Dujardin's account
is based.

The ovaries form longitudinal bands in the walls of the
maiiubrium, and seem to correspond in number with the
oral lobes. They are of a pinkish colour. After the
expulsion of the ova, the maiiubrium remains motionless
for some days and gradually dissolves away.

According to Krohn, the free zooid of Cladonema lives on
a Conferva at the bottom of the sea, and seldom comes to
the surface.

Hob. Devonshire (Gosse). It has also occurred in the
tanks in the Zoological Gardens, and abundantly in Mr.
Holdsworth's aquarium.

[St. Malo (Dujardin): Messina (Krolm): Belgium (Van
Ben.}.]

Genus STAURIDIUM, Dujardin.

Der. from oravpos, a cross.
STAUEIDIA, T. S. Wright, Ed. N. P. Journal (N. S.) for April 1858.

GENERIC CHARACTER. — Stems simple or branched, rooted
by a creeping, filiform stolon, the whole invested by a poly-
pary ; polypites borne at the summit of the stems, subcylin-
drical, with several verticils of capitate tentacula disposed
in the form of a cross, and at some distance below these a
single verticil of false tentacles, or tactile organs, rigid, fili-
form, and covered with palpocils towards the free extremity ,

P2

68 STAUKIDIID^E.

gonophores borne on the body of the poll/pile and origi-
nating free medusiform zooids.

Gonozooid : Umbrella deep bell-shaped; manubrium with
a simple mouth ; radiating canals 4 ; marginal tentacles 4,
nodulated with dieters of thread-cells, and springing from,
ocellated bulbs.

S. PRODUCTUM, Wright.

STAURIDIA PRODUCTA, T. S. Wright, Edinb. N. P. Journ. for April, 1858,

pi. vii. figs. 6, 8.
CORYNE CERBERUS (the young), Gosse, Devon. Coast, 222, pi. xiv. figs. 4-0.

Plate XII. fig. 1.

STEM smooth, simple or slightly and irregularly branched ;
POLYPITES elongate, reddish, the oral extremity opake
white, with 12 tentacles (in the adult state) disposed in
three whorls of four, furnished with numerous palpocils,
the capitula of the uppermost row larger than the rest ;
false tentacles (tactile organs) 4-6, usually suberect;
GONOPHORES borne at the base of the lower tentacles,
pyriform, slightly pedunculate, of a pinkish colour, not
more than one or two on a polypite.

GONOZOOID. — UMBRELLA (at the time of liberation) deeply
bell-shaped, studded with thread-cells ; MANUBRIUM of
moderate length, rose-coloured; MARGINAL TENTACLES
springing from rose-coloured bulbs, on one side of which
is a dark reddish-brown ocellus, very extensile, set along
their entire length with knot-like clusters of thread-
cells, and terminating in a spherical bulb.

I HAVE ab'eady pointed out the identity of the gonozooid
of this species, at the time of liberation, with that of Syn-
coryne eximia (Allman), a member of another genus *.
While within the capsule the marginal portion of the
disk is folded in, and the knotted arms lie in the interior
of the umbrella.

* Ann. N. H. for December 1862.

STAURIDIUM PRODUCTUM. 00

After a time, the investing sac is ruptured by the fre-
quent and vigorous movements of the gonozooid, and the
involved portion of the disk, bearing the tentacles, is slowly
forced out. In a case which came under my observation,
half the margin, with two tentacles, was first pushed out ;
after a few more violent spasms the other half followed ;
and almost immediately the little crystal sphere, with its
rose-coloured pendant and four rose-coloured tubercles,
from which as many beaded arms depended, liberated
itself and moved gracefully through the water.

The Sarsia turricula of Prof. M'Crady's paper on " the
Gymnophthahnata of Charleston Harbour" (Proc. of Elliott
Soc. of Nat. Hist. vol. i. 138, pi. viii. figs. 6-8) appears
to be identical with the gonozooid of S. productum. His
account, however, of the Coryne from which he supposed
it to proceed does not enable me to determine the species
with certainty.

The arms of the Stauridium, as of the Athecata generally,
increase in number with the age of the polypite. The
young are found with only two, three, or four of the capi-
tate tentacles, placed a little below the oral aperture;
after a time the second verticil is developed, and then the
third. The row of false tentacles seems to be produced
contemporaneously with the first series of capitate arms.
The Coryne Cerberus of Gosse is founded on an immature
specimen of the present species.

Hal. Caroline Park, near Edinburgh, on Phutiularia
fulcata (T. S. W.): Ilfracombe, in rock-pools on the Cap-
stone, very abundant (T. H.).

Family VII.— Clavatellidae.

POLYPITES with a single verticil of capitate tentacula ftur-
roundiny the base of the proboscis. GONOZOOIDS
ambulatory.

70 CLAVATELLIDJE.

Genus CLAVATELLA, Hinclcs.

Der. Diminutive of Clava, a club.

GENERIC CHARACTER. — Stems simple and very short,
rising from a creeping filiform stolon, the whole invested by
a polypary ; polypites borne on the summit of the stems,
with a single verticil of capitate tentacula round the base of
the proboscis.

Gonozooids ambulatory, developed in clusters on the lower
portion of the body of the polypite, not enclosed in an in-
vesting sac (ectothcca). Umbrella wanting; radiating
canals 6 or (occasionally] 4 ; marginal tentacles bifurcate,
the outer branch capitate, the inner clavate and terminating
in a suctorial disk ; an ocellus at the base of each tentacle.

CLAVATELLA is nearly related to the Eleutheria of De
Quatrefages, at least so far as the free zooid is concerned.
The polypites of the latter genus have not yet been dis-
covered. They are probably extremely minute, like those
of Clavatella, which had escaped detection until very re-
cently, though widely and abundantly distributed.

These are the only genera at present known in which
the gonozooids are ambulatory. That of Clavatella is a
pretty agile walker and climber, at one time using its suc-
torial disks as feet, and moving with ease even up the per-
pendicular sides of a glass vessel, at another employing
them as hands, and climbing amongst the branches of the
seaweed. That of Eleutheria, on the contrary, seems to
be chiefly scaiisorial in its habits. Both the branches of
its tentacles are surmounted by the globular heads, armed
with thread-cells ; the special locomotive organ is wanting;
and we are not surprised, therefore, to read in M. de
Quatref ages' s interesting 'Memoire' that it drags itself
with difficulty over a smooth surface, but displays con-

CLAVATELLA. 71

siderable activity as soon as it reaches a tuft of coralline
or weed. Eleutheria keeps the mouth turned upwards
when it moves ; Clavatella, on the contrary, always carries
it below.

The important difference in the tentacles, accompanied
as it is by a corresponding difference in habits and mode
of life, must be accounted a generic distinction, and Cla-
vatella, therefore, is not to be ranked as a mere synonym
of Eleutheria.

Considerable diversity seems to prevail in the number
of the arms. I have never met with more than six, and
Krohii* in his very valuable paper gives the same number.
Claparedef, however, states that in most of his specimens
there were eight. Filippi J would regard this difference as
specific ; but of his own specimens, while a large propor-
tion had six arms, 15 per cent, had seven. The number
is so variable that it cannot be accounted a character of
any special significance. The radiating canals also vary
in number, according to the observations of Claparede,
but never exceed six.

I have already pointed out§ the close resemblance which
there is between the reproductive zooid of Clavatella and
the alimentary polypite. In no Hydroid is the structural
identity of these two elements so apparent as in the pre-
sent species. The sexual zooid is a free polypite, with
the lower portion of its arms united by a membrane
closely investing the base of the proboscis, and the upper
portion furnished with a sucker-bearing fork. If the mem-

* " Observations on the Structure and Reproduction of Eleutheria, Q.ua-
tref.," Wiegmann's Archiv, 18GI, p. 157.

t Beobachtungen iiber Anatomic imcl Entwicklungsgeschichte Wirbelloser
Tbiere.

^ Mem. della E. Acad. d. Sci. di Torino, (ser. 2) torn, xxiii.

§ "On Clavatella, a new genus of Coryuoid polypes, and its Eeproduc-
tion," Ann. N. H. for Fob. 1801.

72 CLAVATELLID^E.

brane were extended into a bell, it would be converted into
a (so-called) medusoid ; an equally slight modification
would change it into an ordinary polypite. It is easy to
recognize in the short and wide radiating canals the basal
portions of the tentacles involved in the connecting web.
The canal, according to Krohn, runs down in the axis of
the arm, and penetrates each branch, reaching to its
extremity.

The only additional elements besides are the circular
canal and the ocelli, which may be regarded as simple
organs of sense and the natural accompaniments of a free
and independent existence.

The arms of the sexual zooid, divested of their locomo-
tive appendages, bear an exact resemblance to those of the
alimentary polypite, even exhibiting the same number of
opake- white patches in precisely the same positions ; in-
deed the general resemblance of the two, before the
liberation of the gonozooid, is most striking ; it is only
after its liberation, when it is seen striding along on its
stilt-like legs, the proboscis hanging down as in the swim-
ming forms, that the close relationship is disguised by the
change of posture and habit.

The ova in this genus are produced in the extreme pos-
terior portion of the body, between the ectoderm and
endoderm (Plate XII. fig. 2, «) . The two membranes are
separated more and more widely as the embryos mul-
tiply and increase in size, and the body of the zooid be-
comes much distended. At last the outer wall is ruptured,
and the contained young are successively liberated. The
males are much less common than the females.

The gonozooid of Clavatella multiplies rapidly by gem-
mation, the buds being developed in the interradial spaces,
close to the periphery of the body. Gemmation is con-
fined to the spring, and later on in the season gives place
to the production of ova, as in the common Hydra.

CLAVATELLA PROLIFERA. 73

C. PROLIFERA, Hincks.

CLAVATELLA PROLIFERA, HincJcs, Ann. N. II. (3rd scr.) vii. 73, pi. vii. & viii ;

AUman, Ann. N. II. for May 1864.
ELEUTIIEUIA, Krohn, in Wiegmann's Archiv, 1861, 157; Agassis, N. H. U.S.

iv. 341.

Plate XII. figs. 2, 2 a.

STEM very short, supporting a single polypite, the polypary
smooth and delicate; POLYPITES linear-cylindrical, he-
coming clavate above, very extensile, the oral extremity
and centre of the body opake Avhite ; tentacles (in the
mature zoophyte) 8, with large globular tips; a patch
of opake white just below the capitulum, and another
towards the base.

GONOZOOIDS in two opposite clusters, hemispherical, yel-
lowish white ; RADIATING CANALS very short and wide ;
PROBOSCIS funnel-shaped, opake white; MARGINAL TEN-
TACLES variable in number (6, 7, 8), the capitate portion
resembling exactly the arm of the polypite ; a dark-red
ocellus at the base of each tentacle.

THE polypites of this exquisite species possess a remark-
able power of altering the dimensions of the body. At
times they are greatly elongated and attenuated, and pre-
sent the appearance of most delicate milk-white threads*.
If disturbed, they suddenly contract, and assume a flask-
like form. The body during extreme extension is about
I inch in length.

The tentacles vary in number with age, but do not seem
to exceed eight, four of which are held erect and four de-
pressed. The capitula are large, and thickly covered with
thread-cells. The movements of the polypite are extremely
graceful ; and the extensibility both of the body and ten-
tacles gives it great advantages in pursuit of prey.

During the summer and autumn months, reproductive

* The entlodcrui is white, invested by a transparent ectoderm.

.

71 CLAVATELLID^E.

buds are almost always present ; they are constant in
position, forming two clusters at opposite points on the
lower portion of the body. Each cluster consists of three
or four buds in various stages of development, from a sim-
ple excrescence on the surface of the body to the fully
formed zooid. As it approaches maturity, the movements
of the gonozooid become frequent and vigorous; and at
length the pedicle by which it is attached gives way, and
it enters upon its term of free existence, moving about by
means of its suctorial disks. It now bears a considerable
resemblance to a Lilliputian starfish. In its movements
and mode of life it presents a marked contrast to the
medusiform zooid of other Hydrozoa. The latter is active
and mercurial, dancing gaily through the water by means
of the vigorous strokes of its crystalline swimming-bell.
The former strides leisurely along, or, using the adhesive
disks as hands, climbs amongst the branches of the weed.
In. the latter stage of its existence it becomes stationary,
fixing itself by means of its suckers ; and thus it remains,
the capitate arms standing out rigidly, like the rays of a
starfish, until the embryos are ready to escape.

Claparede states that he has met with specimens in
which there were two ocelli at the base of each arm.

Clavatella prolifera was first discovered at Torquay. It
occurred in the small basins scooped out in the masses of
limestone with which the shores of Torbay are, in many
parts, so thickly strewn, amongst forests of Laomedea
flexuosa and companies of the daisy-anemone in posses-
sion of every chink and cranny, and scattered colonies of the
exquisite little Zoanthus sulcatus. It is found universally
in the higher and smaller pools, and prefers such as
are clean and not much overgrown by weed. It requires
close observation and a keen eye to detect the presence of
the polypites, which are like the finest threads. In a

MYRIOTIIELIDyE. 75

strong light their milk-white colour betrays them. At
the proper season, the ambulatory zooids may be obtained
abundantly in the small tufts of algse that stud the bottom
and sides of the pools.

Clavatella has a very definite range on the coast, not
descending, so far as I have observed, below the higher zone
of the littoral region. Its diffusion is limited, no doubt, by
the structure and habits of its ambulatory gouozooid.

Hub. Torquay : Ilfraconibe : Filey Brigg, Yorkshire :
Whitby (T. H.).

[Nice (Krohn).]

Family VIII. — Myriothelidse.

POLYPITES solitary *, with very numerous, minute, capitate
tentacula scattered over the body.

Genus MYEIOTHELA, Surs.

Der. fivptos, innumerable, and 0»/X/}, a nipple.

CANDELABRUM, De Blainville.
ARUM, Vigurs.
SrAiux, Gosse.

GENERIC CHARACTER. — Polypites solitary, cylindrical, ter-
minating above in a conical proboscis, springing from an
adherent base, which is clothed with a chitinous polypary ;
tentacles very small, capitate, covering the greater portion
of the body.

Gonophores borne on coryniform processes, clustering
round the base of the poly pites, and containing fixed sporosacs.

THIS curious form was first described by Otho Fabricius
in his 'Fauna Grcenlandica/ under the name of Lucernaria

* This term is used to denote that there is only a single primary or ali-
mentary polypite. ( Vide next page.)

70 MYRIOTHELID^E.

jjkrygia. He states that he referred it provisionally to this
genus, and that in many points it was closely related to
Hydra. De Blainville (in 1834) , neglecting this hint, and
failing altogether to appreciate its true affinities, separated it
much more widely from its kindred, and assigned it a place
near Sipunculus, under the generic name of Candelabrum.
In 1849 it was rediscovered by Sars, who gave an admi-
rable account of it as Myriothela arctica, and placed it
amongst the Hydroida, between his Coryna and Syncoryna.
He did not at the time recognize the identity of his zoo-
phyte with the Lucernaria phrygia of Fabricius ; but many
years after, at a meeting of the Northern Scientific Asso-
ciation, he announced that he had seen a specimen of the
latter in the University Museum at Copenhagen, and that
it was neither more nor less than the Myriothela.

Agassiz has lately restored the genus Candelabrum of
De Blainville, on the ground of priority of date ; but as
this author was wholly ignorant of the true nature of the
animal, and has left us no description of it that is of any
scientific value, his generic name must properly give place
to that of Sars, who was the first to characterize it ade-
quately*. The original specific designation conferred by
Fabricius must be retained.

Myriothela is usually described as a solitary polypitc ;
it would perhaps be more correct to say that it is a cluster
of polypites, one of which is fully developed and of large
size and acts as the alimentary zooid, while the others are
small and rudimentary and support the reproductive buds.
The peculiarity is the development of the prolific zooids on
the base of a single primary polypite instead of on the
ccenosarc as in Hydractinia &c.

Mr. Alder has suggested the probability of a close affi-
nity between Myriothela and tlieAcaulis of Stimpson, and

* Vide Allrnan, "Notes on the Hydroida," Ann. N. H. for July 18(31

MTRIOTHELA PIIRYGIA. 77

would place it in the family of the Tululariida. To this
view I am unable to assent, although it has received a cer-
tain measure of support from Prof. All man. The Acaulis
is furnished at first with a verticil of filiform tentacles near
the base of the polypite (though they are said to disappear
subsequently) ; and between these and the upper capitate
tentacles the reproductive buds are developed on the body.
But Myriothela, so far as we know, is destitute of basal
tentacles at all stages of its existence, and the gonophores,
instead of being borne on simple or branched pedicels as in
the Tubnlariidce, are produced on distinct coryniform zooids
— small, rudimentary polypites, which are homologous with
the (so-called) gonoblastidia of Hydractinia or Dicoryne.
It is, as I have said before, a cluster of polypites nearly
related to Coryne ; but its marked peculiarities would seem
to entitle it to stand as the type of a separate family.

M. PHRYGIA, Fabricius.

LUCERNARIA PHRYGIA, Fair. Faun. Greenland. 343.

CANDELABRUM riiRYGii'M, De Slain v. Actinolog. 318.

MYRIOTHELA ARCTICA, Sars, Zoolog. Eeise i Lofoten og Finmarken, 14 ; Gosse,

Marine Zool. 19, fig. 25.

ARUM COCKSII, Vigurs, Eep. Eoy. Polyteck. Soc. 1849.
SrADix PURPUREA, Gossc, Ann. N. H. (n. s.) xii. 125.
CANDELABRUM ARCTICUM, Agassiz, N. H. U. S. iv. 341.

Plate XII. fig. 3.

POLYPITE cylindrical, very extensile ; tentacles extremely
numerous and closely set, covering about three-fourths
of the body, with a reddish-brown spot on the capitulum ;
the basal portion of the body minutely speckled with
white, and crowded with the processes bearing the
gonophores, which are slender, pointed above, with a few
minute wart-like tentacles on the upper portion ; GONO-
PHORES produced a little below the tentacles, subsessile,
globular, when mature of a very large size and a pink

78 MYRIOTHELID^.

colour; the ADHERENT BASE massive, of a dark horn-
colour, sending out a few tubular and root-like prolon-
gations. Embryo actiniform.

Tins extraordinary Hydroid is remarkable for mutability
of form and vigour of movement. The body when elon-
gated extends at times to as much as an inch and a half in
length. In its contracted condition it is somewhat fusi-
form; butSars's epithet " cylindrical" is strictly applicable
to it when extended. For about three- fourths of its length
the body of the primary polypite is completely covered by
the small capitate tentacles (Plate XII. fig. 3, c}} which,
with their reddish tips, give a mottled or variegated appear-
ance to the surface. The basal portion bears a dense cluster
of the small prolific polypites on which the reproductive
buds are developed; these may be seen in frequent and
vigorous motion. They bear a close resemblance to minute
Corynes, having a few tentacles on the upper portion of the
body and carrying the gonophorcs below them. They seem
to be destitute of a mouth. As in Coryne, the reproductive
bodies attain a very large size. The actiniform embryo
has been observed by Mr. Cocks and Mr. Alder ; it con-
tinues (< free for several days, and perambulates on its stilt-
like legs with ease and agility."

Sars describes Myriothela as destitute of a polypary;
but in fact it springs, like others of its tribe, from an adhe-
rent base sheathed in chitine, though it is sometimes
inconspicuous and difficult to detect.

Hub. Under stones, at extreme low water, Gwyllyn Vase,
near Falmouth (Cocks) : Lulworth : Weymouth, nume-
rous under stones and on rocky ledges at spring tides
(Gosse) : Meadfoot, Torquay, on stone (T. H.) : Ilfracombe,
dredged (Leipner).

[Greenland (Fabricius) : Troniso, in 20-30 fathoms
attached to stones or Sertttlarixe (Sars).]

EUDENDRIID.E. 79

Family IX. — Eudendriidse.

Poli/piics borne on a well-developed stem, with a single ver-
ticil of filiform tentacula surrounding the base of u
large trumpet-shaped proboscis.

Genus EUDENDRIUM, Ehrenberg (in part) .

Der. ev well, and SevSpov a tree.

GENERIC CHARACTER. — Stem branched, rooted by a
creeping filiform stolon, the whole invested by a chitinous
polypary ; polypites borne at the extremity of the branches,
vase-shaped or roundish, with a prominent, trumpet-shaped
proboscis and a single verticil of filiform tentacula round
tlit base of it. Gonophores developed from the body of the
polypite below the tentacles, or from the stem, containing
fixed sporosacs — the female simple, the male consisting of
several chambers arranged in moniliform series.

THE Eudendria form a well-marked group. They are
most of them of decidedly arborescent habit, and bear
graceful and often brilliantly coloured polypites, which are
remarkable for their conspicuous funnel-shaped
proboscis.

The gonophores are generally developed on the
body of the polypite, but sometimes occur on the
stem. In many cases the fertile polypite is atro-
phied and disappears, and the reproductive buds
hang in umbelliform clusters at the extremity of
the branches.

The male sporosac is ultimately polythalamic,
consisting of several chambers placed one above another
(woodcut, fig. G). In its first stage it consists of a simple
spherical sac, borne on a peduncle, and enclosing a maim-

80 EUDENDRIIDyE.

brium, in the walls of which the spermatic mass is deve-
loped. Gradually, however, the peduncle lengthens., and
a second sperm-sac is formed upon it immediately below
the first ; sometimes a third follows below the second ; but
this seems to be commonly the limit. This polythalamic
structure is a very simple modification of the
ordinary gonophore. The female sporosac
contains a single ovum, which is more or less
encircled by the loop-like spadix (wood-
cut, fig. 7).

According to Agassiz the colour of the polypite some-
times differs in the two sexes'*.

The genus Eudendrium is widely distributed in the
European Seas, and has representatives in North America.
One of these (E. tenue, A. Agass.) I believe to be identical
with a British species, and E. ramosum, according to
M'Crady, has been found at Charleston. E. rameum
occurs near the North Cape, as well as abundantly on our
own shores, and ranges to the Mediterranean. Sars de-
scribes a new species (E. pusillum) found near Messina,
and Stimpson reports one (E. cinc/ulatum] as occurring at
Grand Manan, Bay of Fundy.

1. E. RAMEUM, Pallas.

TUBULARIA RAMEA, Pallas, Elencli. 83; Johnst. B. Z. (1st eel.) 117, pi. v.
figs. 1, 2 ; Dalyell, Bern. An. of Scotl. i. 50, pis. vi.-x.

TIIOA SAVIGNYI, Lamx. Expos. Meth. 15.

TUBULARIA RAMOSA, Johnst. Trans. Newc. Soc. ii. 253, pi. x.

EUDENDUIUM RAMEUM, JoTinsf. B. Z. (2nd eel.) 45, pi. v. figs. 1, 2; Lands-
borough, Pop. Hi.st. B. Z. 107, pi. ii. fig. 5 ; Alder, North. &
Durh. Cat. in Trans. Tynes. F. C. iii. 103 ; T. 8. Wright, Ed.
New Phil. Journ. (N. S.) for Jan. 1859, pi. ii. figs. 1,2.

Woodcut, fig. 8.

ZOOPHYTE tree-like, much and irregularly branched ; MAIN

* ride his account of E. dispar, N. II. IT. S. vol. iv. p. 288.

EUDENDRIUM RAMETJM. 81

STEM (trunk) thick and coarse, composed of many agglu-
tinated tubes, of a dark brown colour; PRINCIPAL BRANCHES
compound below, but running out into a single tube towards
the extremity, much ramified ; BRANCHLETS simple, alter-
nate, with a few slight rings at their origins ; POLYPITES
vase-shaped, of a reddish colour, with 24 muricatc ten-
tacula ; GONOPHORES (male) in umbclliform clusters,
(female) oval, borne 011 the polypite or scattered over
the stem below it, containing a single yellow ovum.
Average height, when full-grown, G inches.

"THIS is a splendid animal production — one of the most
singular, beautiful, and interesting among the boundless
works of nature. Sometimes it resembles an aged tree,
blighted amidst the Avar of the elements, or withered by
the deep corrosions of time ; sometimes it resembles a
vigorous flowering shrub in miniature, rising with a dark-
brown stem, and diverging with numerous boughs, branches,
and tAvigs, terminating in so many hydrae, wherein red and
yellow intermixed afford a fine contrast to the Avhole."

So writes Sir John Daly ell with justifiable enthusiasm.
The dredger Avill meet with no more beautiful sight than a
fine specimen of this zoophyte, bearing, it may be, a thou-
sand of the flower-like polypites, and laden Avith its bright-
yellow fruit. Its resemblance to an aged tree in miniature
is equally striking.

E. rameum is rooted by a dense, sponge-like mass of
fibres, and sometimes attains a height of eight or nine
inches.

The male gonophores as well as the female are developed
from the polypite ; but complete atrophy of the latter seems
to take place chiefly in the case of the male, and the gono-
phores of this sex are almost always met with in an ad-
vanced state as umbelliform clusters. The embryo on
Issuing from the female sac is a large bright-yellow plauule.

G

82 EUDENDRIIDyE.

Hab. Deep water, on shells, stones, &c. ; widely distri-
buted. It is found in Shetland, in the Clyde, and along
the eastern coast of Scotland and England; very abun-
dantly at Lythara, in Lancashire ; sparingly in Cornwall
(off the Deadman) : in Ireland (east coast).

[Tromso and Hammerfaest in 30 fath. (Sars): Mediter-
ranean (Pallas).]

2. E. RAMOSUM, Linnseus.

SMALL RAMIFIED TUBULAR CORALLINE, Ellis, Corall. 31, pi. xvi.fig. «,?pl. xvii.

figs, a, A.
TUBULARFA RAMosA, Linn. Syst. 1302; Lamk. An. sans Vert. (2nd eel.) ii.

126 ; Lamx. Expos. Meth. 17.
(?) SERTULARIA RACEMOSA, Cavolini.
TUBULARIA TBICHOIDES, Pallas, Elencb. 84.
Ei'DENDRiuM RAMOSUM, Elirenberg, Corall. roth. Meer. 72 ; Johnst. B. Z. 40,

pi. vi. figs. 1, 2, 3.

Plate XIII.

ZOOPHYTE pinnately branched; MAIN STEMS consisting of a
single tube, long and slender, straight, of a chest nut-
brown colour, smooth, or with ringed spaces irregularly
distributed ; BRANCHES alternate, slightly constricted at
their origins and ringed above them, bearing short, sub-
erect ramules, which are more or less aniiulated ; POLY-
PITES large, of a pinkish colour, with about 24 long
white tentacles.

Height about 6 inches.

THE long, simple stems, which are generally of a dark rich
horn-colour, and the slender habit distinguish this species
from the preceding. While there is a good deal of varia-
bility in the branching, it never assumes the truly arbo-
rescent character that belongs to E. rameum. There is
often a considerable amount of annulation on the stems ;
but it is irregularly distributed *.

* "Tuhulis * * * alterne ramoBis passimque annulatis." — Palla*.

EUDENDRIUM ANNULATUM. 83

Hob. On shells &c., generally distributed round the
coasts of Great Britain and Ireland.

3. E. ANNULATUM, Norman.

•; On uhdescribed British Hyclrozo:i, Actinozoa, and Polyzoa," Ann. N. H.
for Jan. 1S64, 83, pi. i\. figs. 1-.°..

Plate XV. fig. 1.

ZOOPHYTE shrubby, densely branched, of a bright full horn-
colour ; MAIN STEMS very thick and strengthened by a
network of anastomosing tubes on their surface ; RA-
MULES extremely numerous, short, and delicate, closely
and distinctly annulated throughout ; POLYPITES with
from 16-20 tentacles ; GONOPHORES (? male) in clusters,
oval, and shortly stalked, from 8-20 in a group.

Height 4 inches.

THE shoots rise from an iiicrusting mat, which consists of
a close network of broad and somewhat flat anastomosing
fibres. The dense shrubby habit, the regular annulation,
and the curious superficial network are distinctive cha-
racters of this fine species.

We know little of the reproduction; but, as in other
Eudendria, the fertile polypite is, ultimately at least,
merely rudimentary.

Hab. " Found in a cave known as * Buness Hall/ which
is one of many caverns, all remarkably rich in animal life,
which penetrate the cliffs on the eastern side of Burrafirth,
the northernmost of the voesof Shetland. It was attached
to the perpendicular sides of this cavern, about a foot be-
neath the water at the lowest spring tide. Other, but
much smaller, specimens were inhabiting a rock-pool just
outside the cave. These last examples, though not more
than an inch or an inch and a half high, were loaded with

EUDENDRIED^E.

reproductive bodies, which, hoAvever, were wholly absent
from their larger brethren in the cave " (A. M. N.) .

4. E. ARBUSCULA, T. Strethill Wright.

"Observations on Brit. Zooph.," Edinb. New Phil. Journ. for July 1859,
113, pi. ix. fig. 5.

Plate XIV. fig. 1.

ZOOPHYTE much and densely branched ; MAIN STEM formed
of a number of tubes agglutinated together, of a dark
horn-colour; BRANCHES also compound towards the base,
becoming simple above, often much divided and sub-
divided, bearing numerous slender and transparent ra-
mules, more or less ringed, which support the polypites ;
POLYPITES white, with many tentacula, and a ring of
large thread-cells round the base of the body ; GONO-
PHORES (male) borne in clusters on short stems, springing
at right angles from the branches, the summit crowned
with a tubercle, containing barbed thread-cells ; (female)
unknown.

THIS species forms bushy tree-like tufts, from 1 to 2 inches
in height, and thickly clothed with snowy polypites. The
branches are ringed near their insertions.

The male reproductive bodies are distributed in clusters
over the zoophyte. Each spermary usually consists of
two spherical sacs^ one above the other, borne on a rather
long peduncle, the uppermost surmounted by the curious
tubercle, with its battery of thread-cells.

Hab. Queensferry, Firth of Forth (T. S. W.).

5. E. CAPILLARE, Alder.

EUDENDKIUM CAPILLARE, Alder, North, and Durh. Cat. in Trans. Tynes. F. C.
iii. 105, t. iii. figs. 9-12; Hincks, Devon and Cornw. Cat., Ann.
N. H. x. (3rd ser.) 360.

EUDENDRTTJM CAPILLARE. 85

CORYMBOGONIUM cAPiLLARE, All man, Ann. N. H. for Aug. 1861, 168.
DICORYNE CAPILLARE, Alder, Supp. North, and Durh. Cat. in Trans. Tynes.

F. C. v. 230.
?EIJDENDRIUM TE.vuE, A. Agassiz, North Amer. Acalephae, 160, fig. 250.

Plate XIV. fig. 2.

STEM very slender and thread-like, pale horn-coloured, and
very transparent, irregularly branched; BRANCHES of
equal thickness with the main stems, ringed at their
origin; POLYPITES vase-shaped, yellowish brown, with
an opake- white proboscis and "between 20 and 30 long
slender tentacles ; GONOPHORES (male) clustered, borne
on short ramules, delicatelij annulated, springing from
the lower part of the stem or the creeping stolon, raised
on peduncles, and with a tubercle on the summit;
(female) somewhat oval, pedunculate, ranged round the
body of the polypite*.

Height of zoophyte from ^ to | inch.

THIS species is remarkable for its great delicacy and trans-
parency. The smooth and slender stems are just tinged
with the faintest horn-colour.

The male sporosacs hang like clusters of fruit from the
extremity of very short branchlets, which occur only 011
the lower portions of the stem or on the stolon, the barren
polypites crowning the summit of the superior branches.
The gonophores are furnished with a tubercle at the top,
like those of E. arbuscula.

Hub. On Antennularia ramosa, Embleton Bay, North-
umberland (R. Embleton) : Firth of Forth , on Delesseria
sanguinea, from about 4 fathoms (Gr. J. A.) : Torbay, on

* There is very little variation in the gonophores amongst the species of
Eudcndrium. The males are usually clustered, the polypite that gives ori-
gin to them disappearing in great part as they advance to maturity. The
polypite that bears the female gonophores seems to be less subject to atropln .
which, however, probably sets in before the liberation of the ova.

86 EUDENDRIII)y£.

Salicornaria farciminoides &c., not uncommon ; near
Polperro, Cornwall (T. H.).

6. E. VAGINATUM, Allnian.

"Notes on the Hydroida," Ann. N. H. for Jan. 1863, (ser. 3) xi. 10.

ZOOPHYTE much branched, polypary deeply and regularly
anmdated throughout ; POLYPITES vermilion, with about
18 tentacula, — the body, as far as the origin of the ten-
tacles, enveloped in a loose corrugated membranous
sheath, which loses itself posteriorly upon the polypary ;

REPRODUCTION UllknOWll.

Height about 1| inch.

Hub. " In rock-pools at extreme low water, spring tides,
Shetland" (G. J. A.).

7. E. INSIGNE, Hincks.

EUDENDRIUM INSIGNE, Hincks, Devon and Cornw. Cat., Ann. N. H. (ser. 3)

ix. 159 and 297, pi. Tii. fig. 2.
HUMILE, Alhnfm, Ann. N. H. for Jan. 1863, (ser. 3) xi. 9.

Plate XIV. fig. 3.

ZOOPHYTE delicate, more or less branched; stem and
branches closely ringed throughout; POLYPITES rather
large, vase-shaped, with about 20 tentacles, red, with
a shade of yellow or brown ; GONOPHORES (male) desti-
tute of a terminal tubercle ; (female) globose, on short
stalks, of an orange colour.

Height (commonly) about a quarter of an inch, sometimes
more.

THE polypary of this species is distinctly annulated
throughout, like that of a Coryne. The polypites are
very graceful in form, and of a reddish-brown colour;
the proboscis, as is very commonly the case in this and

ATHACTYLID^E. 87

allied genera, is opake white, aiid thickly paved with large
thread-cells. There is a circular groove near the base of
the body, from which the gouophores spring — a portion of
the structure which I misinterpreted at first, and which
led me to suppose that there was a shallow cup round the
base of the polypite.

The polypites bearing the reproductive buds are not
confined to any particular portion of the zoophyte, but
are irregularly distributed. In this species I have some-
times found male gonophores borne 011 fully developed
polypites. In other cases they form mere clusters at the
extremity of the branches.

I have little hesitation in identifying the present species
with the E. humile of Allman. His specimens were ob-
tained in much the same locality as those from which I
originally described the species, but were of somewhat
larger growth. His variety corymbifera is probably
founded on examples of E, insigne in which the fertile
polypites were atrophied.

Hab. Torquay, on rocks between tide-marks; Ilfra-
combe; Swanage, Dorset (T. H.).

Family X. — Atractylidae.

Polypites borne on a stem*, with a single wreath of filiform
tentacula surrounding a conical proboscis .

Genus ATRACTYLIS, T. S. Wright (in part).

Der. arpaicros, a spindle.

GENERIC CHARACTER. — Ccenosarc sheathed in a chitinous

* The stem is sometimes rudimentary, and a few species occur in which,
so far as our present knowledge of them goes, it is suppressed altogether ;
but the development of a stem is a prevailing characteristic of the group.

88

polypary ; stems erect, funnel-shaped, developed at intervals
on a creeping stolon ; polypites emerging from the summits
of the stems, into which they are retractile, fusiform, with a
conical proboscis , surrounded by a single verticil of filiform
tentacula. Reproduction by fixed sporosacs, which are
invested by a chitinous envelope and borne on the sides of
the stem.

ATRACTTLIS is distinguished from Perigonimus solely by
its mode of reproduction. A simple fixed sac takes the
place in this genus of the medusiform zooid. The ovary
contains a very large number of eggs, developed as usual
between its two component layers ; and these at a certain
stage are forced, after " a most laborious process of partu-
rition"*, through the ruptured wall of the sac into a kind
of gelatinous nest which crowns it (Plate XVI. fig. 1 b}.
There they are matured into planules. This extracapsular
nidus is not uncommon in the next suborder (Thecaphora] .
Sertularia pumila and Calycella syringa offer examples of it.

A. ARENOSA, Alder.

ATRACTYLIS ARENOSA, Alder, Supp. North. Cat. in Trans. Tynes. F. C. v. 231,
pi. ix. figs. 5-7 ; T. S. Wright, Micr. Journ. (N. S.) iii. 47,
pi. iv. figs. 7-10.

Plate XVI. fig. 1.

STEMS short, funnel-shaped, generally covered with minute
grains of sand or with mud; POLYPITES milk-white, with
long, slender tentacles alternately elevated and depressed,
6-12 in number, according to age; GONOPHOBES pyriform,
shortly stalked, borne on the lower half of the stem,
usually two in number, one opposite to the other.

THE stems of this species, though somewhat irregular in

* Vide " Observations on Brit. Zoophytes;1 by Dr. T. Strethill Wright,
Microscop. Journ. vol. iii. (N. S.).

PERIGONIMUS. 89

form, expand gradually from the base to the top, and do
not present the cup-shaped enlargement above, which
is characteristic of Perigonimus repens, a near ally. The
sanded surface is also a good distinctive mark. The gono-
phores are generally two in number, but three sometimes
occur ; they are constant in position, and produce an
immense number of ova.

Hub. On the undersides of stones and the roots of
Laminariae at Tynemouth and Cullercoats, occasionally
(J. A.) : Largo (T. S.W.) : under stones, and on Laminaria-
roots, Filey Brigg, very common (T. H.).

Genus PERIGONIMUS, Sars.

Der. Trepl, all round, and yovifios, fruit-bearing.
ATRACTYLIS, T. S. Wright (in part).

GENERIC CHARACTER. — Coenosarc sheathed in a chitinous
polypary ; stems branching or simple, rooted by a thread--
like stolon ; polypites fusiform, with a single verticil of fili-
form tentacles round the base of a conical proboscis ; gono-
phores developed from the ccenosarc.

Gonozooids free and medusiform. Umbrella (at the
time of liberation) deep bell-shaped ; manubrium short ;
radiating canals 4 ; marginal tentacles 2 or 4 (increasing
in number with age], springing from non-ocellated bulbous
bases.

A GROUP of minute zoophytes of simple habit, or with
very slight branching, which usually colonize the shells and
opercula of various univalve mollusks. If we except P.
linearis, which is doubtfully referred to this genus, all the
species produce gonozooids that are nearly identical in
external appearance.

90 ATBACTYLIDJE.

The operculum is a very favourite site for the Periyo-
mmMS-settlement, affording no doubt peculiar facilities for
procuring an abundant supply of food. The alliance is far
from uncommon between the stationary zoophyte and
the mollusk or the restless Hermit Crab, the former securing
the advantages without the toils of a vagrant life, and
sharing the spoil without the fatigues of the chase.

1. P. REPENS, T. S. Wright.

EUDENURIUM PUSILLUM, Wright, Proc. Koy. Phys. Soc. Edinb. 1857, p. 231,

pi. ii. figs. 8, 9; Ed. N. P. Journ. (N. S.) vi. pi. ii. figs. 8, 9.
ATRACTYLIS REPENS, Wright, Proc. Koy. Phys. Soc. Edinb. 1858, p. 450, pi. xsii.

figs. 4, 5; Ed. N. P. Journ. (N. S.) ix. (1859,) 108, pi. i.

figs. 4,5; Alder, Supp. Nortb. Cat. in Trans. Tynes. F. C.v. 230.
PERIGONIMUS REPENS and vvsiLixs,Allman, Ann. N. H. for May 1864.
PERIGOMMUS MINUTUS, All-man, Notes on Hydroida, Ann. N. H. for January

1863.

Plate XVI. fig. 2.

STEMS erect, simple or bifurcate, more or less dilated and
cup-shaped above, from g to \ inch in height; POLYP IT E
small, club-shaped, white, partially retractile into the
upper part of the tube ; tentacles from 4-1 2, according
to age; GONOPHORES pedicellate, borne on the stems at
various heights.

GONOZOOID. — UMBRELLA mitre-shaped, with numerous
thread-cells in its substance ; MANUBRIUM 4-lipped ;
MARGINAL TENTACLES, at the time of liberation, 4,
springing from yellowish-brown bulbous bases at the
termination of the radiating canals — two very long, two
rudimentary*.

DR. WRIGHT first described this species under the name
of Endendrium pusillum. In a subsequent paper he trans-
ferred it to the genus Atractylis, and changed the specific
name to repens. As such it is quoted in his own writings

* The latter seem to be sometimes undeveloped at the time of liberation,
but they soon make their appearance.

PERIGONIMUS REPENS. 91

and in those of other zoophytologists, and I therefore
retain the later designation to avoid confusion.

He has given a graphic description of the habits of the
gonozooid. " When first separated from the zoophyte,
it seeks the surface of the water with long zigzag bounds,
carrying its tentacles closely coiled in spirals. Having
remained swimming there for a short time, it begins to
sink slowly with the mouth of its bell uppermost, and the
tentacles, uncoiling themselves, stream behind, to a distance
of more than twenty times the length of the bell, in straight
lines or graceful curves, sweeping the water in search of
prey." . . . " A jar of these lively creatures, some swimming
rapidly about like small frogs, with their half-coiled ten-
tacles jerking backwards at each stroke, others descending
headlong in flocks like the falling train of a rocket, and
all glittering under oblique illumination in the dark water,
forms one of not the least interesting of those scenes of
beauty which are of daily occurrence to the naturalist."

The gonozooid at the time of detachment has only two
arms fully developed ; but two more are present in a very
rudimentary state, or soon bud from the two smaller mar-
ginal tubercles. Dr. Wright has observed* that after a
time four other tubercles appear on the marginal canal,
and possibly the multiplication of the tentacles may pro-
ceed much further.

The P. minutus of Allman, judging from the description
of it, for unfortunately we have no figure, is identical with
P. repens in all but one or two trifling particulars. The
umbrella of its gonozooid is described as having " a some-
what conical form " at the summit, and its reproductive
buds as borne on much longer peduncles than those of P.
repens. Now in Dr. Wright's first figure the swimming-

* '• Observations on British Protozoa and Zoophytes," Annals N. H. for
August 1861 — under Atractylis palliata.

92 ATEACTYLID^.

bell is represented as slightly produced and pointed at the
top ; and though in a subsequent figure it is rounded, it is
fair to infer that this diversity arose from his having had
the two forms under observation*. The variation I cannot
regard as of much importance.

Nor is the difference in the length of the peduncle which
supports the gonophore in itself a point of greater moment.
These slight variations, if constant, might fairly be taken
account of along with other distinctive characters ; but as
the sole criteria of the species they seem to me to be insuf-
ficient.

Prof. Allmaii also refers to the entire absence in his
species of the two smaller tentacles, at the time of liberation.
But Dr. Wright's latest note on his species implies that,
in some instances at least, they are not developed on the
gonozooid of P. repens till a subsequent period ; and, as I
have often observed (in the case of Podocoryne cameo),
there is very great diversity in the time at which the mem-
bers of the second set of tentacles make their appearance.

From these considerations, and desiring to avoid the
undue multiplication of species, though I must always dis-
sent from Prof. Allman's judgment with hesitation, I pre-
fer to rank P. minutus as a synonym of P. repens.

Hub. On Sertularians and the Spider Crab, Firth of
Forth (T. S. W.) : on Dentalium entails, the operculum of
Fusus antiquus, and other shells, from the fishing-boats,
Cullercoats (J. A.) : (P. minutus) " forming a fringe round
the edge of the operculum of Turritella communis, dredged
in Busta Voe, Shetland. Out of between twenty and
thirty specimens of living Turritella examined, not one

* I have a characteristic drawing of P. repens by Mr. Alder, representing
the reproductive bodies in situ, borne on short peduncles. It is accompanied
by a figure of the free zooid, in which the umbrella is distinctly produced
and conical at the .summit.

PERIGON1MUS PALLIATUS. 93

was free from this remarkable little zoophyte" (G. J. A.):
Ilfracombe, on stones (T. H.).

2. P. SESSILIS, T. S. Wright.

EUDENDRIUM SESSILE, Wright, Edinb. New Phil. Journ. (N. S.) vi. 90, pi. Hi.

figs. 16, 17.

ATRACTYLIS SESSILIS, Wright, Edinb. New Phil. Journ. (N. S.) ix. 109.
PEIUGONIMUS SESSILIS, Allman, Ann. N. H. for May 1864.

Plate XVII. fig. 1.

POLYPITES supported on a very short ringed stem, or sessile,
red or white, with 8 tentacles, sheathed up to the ten-
tacles in a delicate membranous tube ; GONOPHORES sessile,
borne on the creeping stolon, close to the polypites, and
often in pairs.

GONOZOOID identical with that of the preceding species.

Hab. On shells from deep water, Firth of Forth, and
on rocks about Granton (T. S. W.).

3. P. PALLIATUS, T. S. Wright.

ATRACTYLIS PALLIATA, Wright, Ann. N. H. for Aug. 1861, 129, pi. iv. figs. 6, 7-
PERIGONIMUS PALLIATUS, Allman, Ann. N. H. for May 1864.

Plate XVII. fig. 2.

STEMS short; POLYPITE minute, fusiform, white, with 8
alternating tentacles, the body clothed up to the border of
the mouth with a gelatinous envelope*; GONOPHORES
borne on the stolon, of large size.

GONOZOOID. — UMBRELLA subcylindrical, with thread-cells ;

MANUBRIUM 4-lipped ; MARGINAL TENTACLES 2, Opposite,

long, the intervening canals terminating in small bulbs.

OF this zoophyte Dr. Wright says, "When first observed,
its closely set and dense white polypes, surrounded by their

* " With a thick layer of ' colletoderm.' "—Wright.

ATRACTYLID.E.

gelatinous envelopes, were mistaken for a mass of minute
ova *#•*•*. The medusoids are of great size when com-
pared with the very minute polype, and resemble exactly
those of Atractylis (Perigonimus] repens. I have not
witnessed any further development in them after their
separation from the zoophyte."

Hab. On a shell inhabited by Pagurus Bernhardus, at
Granton, Firth of Forth (T. S. W.).

4. P. VESTITUS, Allman.

" Notes on the Hydroidci," Ann. N. H. for July 1864.

STEMS from half a line to two lines in height, greatly dilated
towards the summit, simple, or occasionally with one or
two short branches; POLYPARY yellowish brown, with
adherent particles of sand ; POLYPITES with from 6-10
tentacles, usually held in extension, alternately elevated
and depressed, a delicate continuation of the polypary
extending over the whole of the body beyond the tentacles
and almost to the margin of the mouth; GONOPHORES
produced, for the most part, on the stem, occasionally on
the stolon, borne on long peduncles, which are invested
for about half their length by the polypary.

GONOZOOID. — UMBRELLA (at the time of liberation) oviform,
much contracted towards the mouth, the walls very thin
and with minute thread-cells immersed in them ; MANU-
BRIUM with four shallow lips ; MARGINAL TENTACLES 2,
opposite, with non-ocellated bulbous bases, the interve-
ning radiating canals terminating each in a smaller bulb.

THE only character of any importance, so far as I can
judge, which separates this form from the P. palliatus of
Wright is the shape of the umbrella at the time of libera-
tion. In Prof. Allmair's specimens the bell was contracted
towards the mouth, and was therefore oviform, instead of
cylindrical as in Dr. Wright's zoophyte. The other dif-

PERIGONIMUS SERPENS. 95

ferences noted by Allraan are, that in P. vestitus the stem
is rather more developed, and that its reproductive bodies
are chiefly (but not exclusively) borne on the stem, whilst
those of P. palliatus, as observed by Wright, were confined
to the creeping stolon. Further investigation may pro-
bably show that the two forms must be united ; it is cer-
tainly needed to prove that they are distinct.

Hub. On an old Buccinum-shell, Firth of Forth, asso-
ciated with Hydr actinia echinata (G. J. A.).

5. P. SERPENS, Allman.

" Notes on the Ilydroida," Ann. X. II. for January 1863.

Plate XVI. fig. 3.

STEMS erect, short, simple, tapering slightly downward, about
2 lines in height; POLYPARY delicate, transparent, not
dilated at the base of the polypites ; POLYPITES reddish
orange, retractile, the body oval, with about 12 or 14 ten-
tacles, which are held in complete extension, alternately
elevated and depressed; GONOPHORES produced on the
creeping stolon, and elevated on rather long peduncles.

GONOZOOID. — UMBRELLA dome-shaped (at the time of
liberation), with the vertical slightly exceeding the
transverse diameter; MANUBRIUM reaching to about one-
half the depth of the bell, with a simple mouth ; MARGINAL
TENTACLES 2, opposite, very extensile, and with large
reddish-orange bulbs at the base, the intermediate
radiating canals terminating each in a very small bulb-
ous dilatation.

THIS is a very brilliant little zoophyte. The polypites,
during complete extension, are almost cylindrical, and rise
a good way above the top of the stem. They are of a
vivid reddish- orange colour, with the exception of the
tip of the proboscis, which is whitish. The coenosarc
is of the same bright tint as the body of the polypite,
so that a colony presents a very gay appearance.

90 ATRACTYLIDJE.

The polypary of this species is extremely delicate, yield-
ing like a mere skin to the movement of the polyp ites.

Hab. On the stems of Halicornaria setacea, from about
12 fathoms, Torbay (G. J. A.) : on rocks and Laminaria,
under the lower ledges, Capstone, Ilfracombe ; Filey Brigg
(T. H.).

Species doubtfully referred to this genus.

P. (?) LINEARIS, Alder.

ATRACTYLIS LINEARIS, Alder, Supp. North. Cat. in Trans. Tynes. F. C. v. 230,

231, pi. x. figs. 1-3.
PERIGONIMUS ? LINEARIS, Attman, Ann. N. H. for May 1864.

Plate XVII. fig. 3.

STEMS linear, horn-coloured, unbranched, (?) nearly smooth,
a little undulating, and slightly wrinkled on the lower
part; POLYPITE slender, retractile — with 8 long tentacles,
alternately elevated and depressed; GONOPHORES pear-
shaped or subglobular, set two or three together on the
stem.

GONOZOOID. — UMBRELLA globose, slightly truncated below,
with a contracted aperture ; MANUBUIUM inconspicuous,
branched at the base; MARGINAL TENTACLES 4, subcla-
vate, springing from semicircular yellowish lobes.

Height of zoophyte \ inch.

THE stems of this species rise much higher, and are pro-
portionally more slender, than those of P. repens, and
are not so much expanded at the aperture. In the young
state, however, it is difficult to distinguish the two species.
The gonozooids are very different; but we need a fuller
and more precise description of those of P. linearis than the
condition of Mr. Alder's specimens permitted him to give.
Hab. On Turritella communis, Astarte Danmonia, and
other shells from deep water, Cullercoats (J. A.).

PERIGONIMUS COCCINEUS. 97

P. (?) MINIATUS, T. Strethill Wright.

ATRACTYLIS MINIATA, T. S. Wright, Observations on Brit. Zooph., Micr. Journ.
(N. S.) iii. 48. "

ZOOPHYTE tree-like, branches given off at an acute angle
from the stem, crooked, wrinkled, but not ringed, coeno-
sarc yellow ; POLYPITES with 8 alternate tentacles, oral
cavity silvery, lining of the stomach bright red-lead
colour; REPRODUCTION unknown.

THIS zoophyte forms little "gnarled, shrubby" tufts about
an inch high. " The bright-yellow colour of the polypary
(ccenosarc) at once strikes the eye, which is also arrested
by the gaudy colour of the minute polyps. These appear
to be maTked by two broad, internal patches, — one corre-
sponding to the buccal cavity, of a dense silvery white ; the
other to the cavity of the stomach, of a brilliant reddish-
orange.^ (Wright.}

This species can only be placed provisionally until the
reproductive bodies have been observed.

Hub. On stones at Largo, exposed at the lowest tides :
Granton (T. S. W.).

P. (?) COCCINEUS, T. S. Wright.

ATRACTYLIS COCCINEA, T. S. Wright, Observations on Brit. Zooph., Ann.
N. H. for Aug. 1861, viii. (ser. 3) 130.

STEMS about a quarter of an inch high, of a rich pinkish
cream-colour ; POLYPITE fusiform, set at an obtuse angle
to its stalk, not retractile*, crimson or pink, with 8 alter-
nating tentacles, four long and four short ; REPRODUCTION
unknown.

THE stems are given off from an open network of milk-

* Sars makes the non-retractility of the polypite one of the characters of
his genus Perigonimus. But forms, otherwise most nearly allied, differ in
this respect ; and the character is certainly not of sufficient importance to
justify their separation.

H

98

ATRACTYLID.E.

white fibres, and bear at their summits a single crimson
polypite with transparent, colourless tentacles. " This
beautiful little zoophyte, when seen with a single lens, pre-
sents a perfect garden of minute animal flowers covering the
roots of the seaweed." (T. S. Wright.}

Hab. Inch Garvie, Firth of Forth, on roots of Laminaria
saccharina (T. S. W.).

P. (?) BITENTACULATUS, T. S. Wright.

ATRACTYLIS BITENTACULATA, Wright, Journ. Anat. & Physiol. i. 334, pi. xiv.
fig. 5.

STEMS very short; POLYPITES minute, club-shaped, non-
retractile, each furnished with two
erect tentacles ; REPRODUCTION ^i. 9.

unknown.

THE polypites are thickly clustered
on a retiform stolon. "They have
the habit, like that of Lar (Gosse),
of quickly and repeatedly bending
down the body until the mouth is
brought close to the surface on which
the zoophyte grows."

Hob. Found in a Pecten-shell
dredged from the Firth of Forth, near Inch Keith (T. S.W.).

P. (?) QUADRITENTACULATUS, T. S. Wright.

ATRACTYLIS QUADEITENTACULATA, Wright, Journ. Anatom. & Physiol. i. 334,
pi. xiv. fig. 6.

POLYPITES sessile, short, columnar, non-retractile, with 4
alternate tentacles — two long and depressed, two very
short and nearly at right angles to the body.

HYDRANTHEA.

99

THE shorter tentacles were occasionally absent on Dr.
Wright's specimen. I cannot but suspect that both the
present and the preceding species will prove to be imma-
ture forms.

Ha b. Found creeping on the side of a vessel of sea- water
containing shells and zoophytes dredged from the Firth
of Forth (T. S. W.).

Genus HYDRANTHEA, Hincks.

Der. From Hydra, a genus of Hydroida, and avGos, a. flower.

GENERIC CHARACTER. — Stems very short (rudimentary),
rising at intervals from a network of anastomosing tubes,
the ivhole Invested by a polypary ; poly piles borne singly on
the stems, elongate, fusiform ; tentacles filiform, in a single
circle surrounding a low conical proboscis, each alternate
tentacle bearing a prominent tubercle composed of large bean-
shaped thread-cells ; gonophores large, borne on peduncles,
which spring from the creeping stolon, not invested by the
polypary, containing fixed sporosacs.

IN Hydranthea the stem is very slightly developed, and
the polypite is not retractile within it. The tentacles are
very numerous and surround a somewhat ample disk, in the

H

100 ATBACTYLID^E.

centre of which rises a short proboscis. They are held al-
ternately elevated and depressed, and each of the drooping
arms bears near its base one of the curious bosses that
constitute so striking a feature of this zoophyte. They
consist of a number of elongate bean-shaped thread-cells,,
piled together so as to form silvery-white prominences on
the lower side of the tentacles — a girdle of pearls round
the base of the tentacular ring.

The gonophores are of great size and are supported on
a rather long peduncle, the base of which is invested by
the polypary.

They contain a single sporosac, from the bottom of which
proceed four much-branched vessels, terminating near the
top in blind extremities and immediately enclosing the ova,
which fill with a dense mass the interior of the cavity. I
have not detected any traces of a manubrium. The ecto-
theca, or outer envelope of the gonophore, is filled with
the long bean-shaped thread-cells, which are also present
in amazing numbers in the ectoderm of the coenosarc.

H. MARGARICA, HinclvS.

ATRACTYLIS MARCARICA, Hincks, Ann. N. H. for Jan. 1803, (ser. .3) vol. xi.
45, pi. ix. fig. 4.

Plate XIX. fig. 1.

STEMS invested by small, somewhat funnel-shaped exten-
sions of the polypary ; POLYPITES white, with a tinge of
yellowish colour on the thickest part of the body, slightly
retractile, tapering downwards, swollen in the centre,
and expanding towards the upper extremity, with about
30 tentacles, alternately elevated and depressed, and
webbed at the base ; GONOPHORES produced singly or in
pairs close to the polypites, globular, the peduncle tapering
downwards and enclosed at the base by a small chiti-
nous cup.

GARVEIA. ] 01

THE poly piles, with their numerous tentacles, bear some
resemblance to a full-blown flower. The pearly bosses,
which are of a lustrous white when seen against a dark
ground, are very conspicuous, and form a unique and
beautiful garniture. The web connecting the tentacles
extends but a short distance above the base.

The gonophores (female), when fully developed, exceed
the polypites considerably in size, and contain a very large
number of ova. I have counted 300 that had bceu pressed
out of a single sporosac. The branched gastrovascular
vessels are orange-coloured.

Hub. Ilfracombe, on Flustra foliacea and on this only,
in about 7-10 fathoms off the Capstone. The Flustra is
very abundant in this locality; and almost every bunch that
comes up is more or less invested by the Hydranthea, which
covers it with its delicate network and multitudes of
minute polypites.

Genus GARVEIA, T. S. Wright.

Der. Named from Inch Garvie, in the Firth of Forth.

GENERIC CHARACTER. — Stems compound and branched,
roofed by a filiform stolon, the whole invested by a polypary ;
polypites fusiform, with a single verticil of tentacles, which
are not alternately elevated and depressed, surrounding a
conical proboscis ; gonophores borne on the summit of short
branches springing from the stem or the stolon, and con-
taining fixed sporosacs.

IN this genus the tentacles, contrary to the general rule,
are held erect in one uniform series, and not alternately
elevated and depressed. The gonophores spring from
branches terminating above in a shallow cup, which exactly
resemble those that support the polypites.

102 ATRACTYLHXE.

G. NUTANS, T. S. Wright.

GARVEIA NUTANS, Wright, Ed. N. P. Journ. (N. S.) for July 1859, 109,
pi. viii. fig. 5.

ECDENDRIUM (CoRYTHAMNIUM) BACCIFEBUM, Allman, Notes OH Hydr. ZoOpll.,

Ann. N. H. for July 1859.

Plate XIV. fig. 4.

ZOOPHYTE about an inch in height, irregularly branched;
MAIN STEM composed of a few aggregated tubes, becoming
gradually attenuated as it gives off its branches, and at
last consisting of a simple tube; branches slender, slightly
wrinkled, often bent abruptly a little behind the termi-
nal polypite, expanding at the extremity into a delicate
funnel-shaped cup; POLYPITES fusiform, the body red,
with about 10 thick, orange tentacles ; GONOPHORES
remarkably large, oval, each borne on a long peduncle,
which issues from the summit of a short ramulus, — ova
of a deep orange-colour.

IN its perfect state the main stem of this zoophyte is com-
posed of a bundle of delicate tubes, agglutinated together,
which diverge at intervals so as to form branches, until at
length, towards the extremity, it has dwindled down to a
single tube. The polypary is wrinkled transversely (at
times almost annulated) throughout. It expands at the
extremity of the branches into a cup, which is exceedingly
delicate and merely covers the base of the polypite.

The polypites are small and chiefly remarkable for their
brilliant colours, the body being red, according to Wright,
and the tentacles yellow. The prevailing colour of the
zoophyte seems to be orange. Dr. Wright has remarked
that, "when irritated, the zoophyte bends all its polyps
downwards, like flowers drooping on their stalks " — a cir-
cumstance that has suggested the specific name.

The ramules that support the reproductive bodies dilate
at their extremities, like the polypiferous branches, into a

BIMEBIA VESTITA. 103

cup, from whose centre the long peduncle of the gonophore
springs. They occur on the stem and primary branches,
and also on the fibrous mat from which the zoophyte rises.
Hob. Inch Garvie (T. S. W.) : on rocks, zoophytes, and
seaweeds near low- water mark, Firth of Forth (G. J. A.) :
Shetland (T. H.).

Genus BIMERIA, T. S. Wright.

Der. Formed from the name of the Bimer Eock, iu the Firth of Forth.
MANICELLA, Allman.

GENERIC CHARACTER. — Stems branched, rooted by a
thread-like stolon, the whole of the ccenosarc enclosed in a
chitinous polypary ; polypites vase-shaped, with a single
verticil of filiform tentacles, the body and the lower part of
each tentacle clothed in an opake-brown membrane ; gono-
phores borne on short ramules developed on the stem and
branches, and containing fixed sporosacs.

B. VESTITA, T. Strethill Wright.

BIMERIA VESTITA, T. S. Wright, Edinb. N. P. Journ. (N. S.) for July 1859,

109, pi. viii. fig. 4 ; Allman, Ann. N. H. for May 1864.
MANICELLA FUSCA, Allman, Ann. N. H. for July 1859, and August 1859.

Plate XV. fig. 2.

STEM very slender, branched, — the branches alternate, spi-
rally corrugated above their origins, bearing a few short
ramules ; the polypary of a dull brown colour, covered
with minute particles of earthy matter and sand, and
continued as a membranous envelope over the body of
the polypite and the lower half of the tentacles ; POLY-
PITES with a slightly alternating series of about 16

104 A.TRACTYLIDJE.

slender tentacles; GONOPHOIIES ovate, enveloped by the
polypary, borne on the summit of short branches, which
are wrinkled spirally.

WE have two independent accounts of this zoophyte, from
Wright and Allman, who discovered it about the same
time. For I have little doubt of the identity of the Bimeria
vestita and the Manicel/a fusca of these authors, although
the former is described by Wright as destitute of a pro-
boscis, while the latter, according to Allman, has this organ
well-developed. The proboscis amongst the Hydroids is
constantly changing its form and assuming the most diffe-
rent appearances, being sometimes extremely prominent,
and at others so much contracted as to be scarcely visible.
As the two zoophytes perfectly agree in other characters,
it is probable that this slight discrepancy between the
descriptions merely points to a difference in the condition
of the specimens examined.

The polypary of Bimeria, when divested of its earthy
coating, is transparent and of delicate texture. The whole
habit of the zoophyte is slender, the branching is very
regular, and there is no expansion towards the terminal
aperture. The most marked character is the membranous
envelope, or extension of the polypary, which involves the
body of the polypite and forms a rather thick sheath round
the lower portion of the tentacles. Dr. Wright has
remarked that the unclothed half only of the arms is fur-
nished with thread- cells.

Hub. On the Bimer Rock, near North Queensferry, and
on Inch Garvie, Firth of Forth (T. S. W.): Firth of Forth,
" attached to other zoophytes and seaweeds near low water,
spring tides" (G. J. A.): Whitby, Yorkshire; Torbay and
Salcombe, South Devon, dredged on other zoophytes, not
uncommon (T. H.).

DICORYNE CONFERTA. 105

Genus DICORYNE, Allman.

Der. From Sis, double, and vopvvr), a club.

GENERIC CHARACTER. — Stem branched or simple, rising
from a creeping, filiform, and anastomosing stolon, the whole
invested by a polypary ; polypites (alimentary] fusiform,
with a single verticil of filiform tentacula round the base of
a conical proboscis ; gonophores borne on rudimentary poly -
pites, destitute of tentacles, which are developed on the stems
or on the creeping stolon ; gonozooid natatory, ciliated over
its entire surface, and having two filiform tentacles diverging
from the posterior end.

D. CONFERTA., Alder.

ECDENDRIVM (?) coNFERTUM*, Alder, Durh. & North. Cat. in Trans. Tynes.

Nat. F. C. iii. 103, pi. i. figs. 5-8.

DICORYNE STRICTA, Allman, Ann. N. H. (3rd ser.) iv. 370.
DICORYNE CONFERTA, Allman, Ann. N. H. (3rd ser.) viii. 1G8 ; Ahlcr, Supp.

to North. Cat., Trans. Tynes. N. F. C. v. 228, pi. viii. figs. 1, 2.

Plate XVIII. fig. 1.

STEM simple or irregularly branched, the branches erect ;
polypary of a light brown colour, strongly annulatecl
across, slightly dilated and everted at the extremities of
the branches ; ALIMENTARY POLYPITES rather large, fusi-
form, white or pale flesh-coloured, with a verticil of
about 16 tentacles; FERTILE POLYPITES slender, fusiform,
covered with thread-cells above, and bearing the gono-
phores in clusters round their base ; GONOPHORES oval,
shortly stalked.

GONOZOOID oval, pointed at one end, expanded and trun-
cated at the other, from which the two long tentacles
diverge.

* Mr. Alder identifies with this species the Tubu.hinu described by John-
ston in the 'Trans, of the N. II. Soc. of North umb.. Durh., and Newcastle-
<m-Tyno,' li. '2^:'>.

106 ATRACTYLIDJS.

DICOETNE CONFEETA grows iii dense masses on old univalve
shells. Its principal shoots rise to a height of about
half an inch and are irregularly branched. The branches
are erect, " ascending at a very acute angle from the
stem," so that the habit is slender and compact. Besides
the taller shoots, there are generally many short, unbranched
stems, bearing single polypites. These are chiefly of the
proliferous kind ; and I have seen a large portion of the
surface of the shell, over which the zoophyte was spreading,
densely covered with a multitude of them, heavily laden
with the clustering fruit. The fertile are also mingled
with the alimentary polypites on the larger shoots ; but in
the specimen to which I have referred, the latter formed an
inconsiderable element, compared with the thick under-
growth that surrounded them.

The number of the tentacles is variable. It sometimes
reaches 16, but Alder gives 10 as the usual complement.

The remarkable free zooid of ilieDicoryne is unique, so far
as our present knowledge goes, and is extremely interesting
as an intermediate form. It consists of a sexual polypite
(manubrium) furnished with two tentacles, which repre-
sent the more usual natatory organ, while simple ciliary
action replaces the propulsive movement of the swimming-
bell. It swims, according to Allman, " with its body in a
vertical position, carrying the posterior or tentacular extre-
mity uppermost, and maintaining all the time a constant
rotation on its longer or vertical axis." The female zooid
produces two ova.

Hab. On old shells of Buccinwn undatum and Fusus
antiquus from deep water, Cullercoats (J. A.) : Orkney, in
about 3 fathoms, on an old Buccinwn undatum tenanted
by a Hermit Crab (G. J. A.) : Shetland, on Turritdla &c.
(A. M. N.).

HETEROCOKDYLE CONYBEAREI. 107

Geuus HETEROCORDYLE, Alhnan.

Der. From erepos, dissimilar, and KopdvXt), a club.

GENERIC CHARACTER. — Stems simple or branched, rising
from a creeping filiform and anastomosing stolon, the whole
invested by a polypary ; polypites fusiform, with a single
verticil of filiform tentacula round the base of a conical pro-
boscis ; f/onophores borne on rudimentary polypites, desti-
tute of tentacles, developed directly from the creeping stolon,
containing fixed sporosacs.

H. CONYBEAREI, Allmau.

Ann. Nat. Hist, for July 1864, (Srdser.) xiv. 59, pi. ii.

Plate XVIII. fig. 2.

STEMS branched or simple, crowded on the creeping stolon,
the longest attaining a height of about 4 lines ; poly-
pary transversely corrugated, slightly dilated at the base
of the polypites, ash-brown ; POLYPITES with about 12
tentacles, alternately erect and depressed, presenting a
slightly clavate outline at their extremities; GONOPHORES
borne on erect, club-shaped shoots, thickly set with
thread-cells above, which spring out of a short tubular
process from the surface of the creeping stolon, with
very short peduncles, densely crowded, commencing a
little behind the upper extremity of the shoot and ex-
tending to within a short distance of its base.

THIS species closely resembles, in general appearance,
Dicoryne conferta ; but it is of humbler growth and some-
what stiffer habit, and is further and chiefly distinguished
by its simple, fixed sporosacs.

Hab. The Harbour of Glengariff, co. Cork, on old uni-
valve shells tenanted by Hermit Crabs (G. J. A.) : Oban,
on Buccinum, near low- water mark (T. H.).

108 ATRACTYLID^E.

Genus BOUGAINVILLIA, Lesson.

Der. Named after a distinguished French voyager, Admiral Bougainville.

HIPPOCRENE, Mertens, Mem. Acad. St. Petersbourg, 1835, 229.
MAIUJELIS, Steenstrup, Vidensk. Medel. for 1849-50, 43.

GENERIC CHARACTER. — Stem branched, rooted by a fili-
form stolon, the whole ccenosarc invested by a polypary ;
pohjpites fusiform, with a single wreath of filiform tentacles
round the base of a conical proboscis ; gonophores developed
from the branches and originating free zooids.

Gonozooid : Umbrella (at the time of liberation] deep
bell-shaped ; manubrium shorter than the bell, with 4 oral
tentacles ; radiating canals 4 ; marginal tentacles 8, borne
in pairs on bulbs at the termination of the canals, with an
ocellus at the base of each.

As the zooid advances towards maturity the tentacles of
the manubrium become branched, and those on the marginal
bulbs increase considerably in number.

IT is a curious fact, and one that strikingly illustrates
the difficulty attendant upon the classification of the
Hydroida, that the sexual zooid of Corynopsis, one of the
Podocorynidce, is identical with that of the present genus,
at least in its earliest stage.

The Margelis of Steenstrup has been adopted by
Agassiz for the members of Lesson's genus Bougainvillia,
which have " a long, slender digestive cavity, with but
slightly branching tentacles." But the differences be-
tween the two sections, which are confined to the repro-
ductive element, seem to me to be of slight significance,
and quite insufficient to justify the dismemberment of a
group that exhibits in its leading features so definite a
type of structure.

BOTJGAINVILLIA RAMOSA. 109

1. B. RAMOSA, Van Bencden.

EUDENDRIUM RAMOSUM, Van Ben., Rech. sur les Tubul. 56, pi. iv. (with the

exception of fig. 2).

TUBULARIA RAMOSA, Dcili/dl, Rem. An. Scotl. i. 64, pi. xi.
MEDUSA OCILIA and DUODECILIA (the free zooid), Daly. ibid. 66 & 72, pi. xi.
ATIUCTYLIS RAMOSA, T. S. Wright, Edinb. New Phil. Journ. (N. S.) for Jiiii.

1859, vol. viii. pi. i. figs. 1, 2, 3.
MARGELIS RAMOSA, Agassiz, N. H. U. S. iv. 344.
BOUGAINVILMA RAMOSA, All tnan, Ann. N. H. for May 1864.

Plate XIX. fig. 2.

ZOOPHYTE much branched, of a yellowish horn-colour;
MAIN STEMS and larger branches thick, composed of
many delicate tubes ; the branches alternate and some-
ivhat spirally disposed, bearing numerous short ramules,
which dilate at the extremity into a kind of cup, within
which the polypite is in great part retractile • POLYPITES
with nearly 20 white tentacles when adult; GONO-
PHORES borne in pairs or clusters on the ramules, a little
below the cup-like expansion, pyriform, pedunculate,
invested by a delicate capsule, and containing a single
zooid.

GONOZOOID. — UMBRELLA (at the time of liberation) deep
bell-shaped, without thread-cells ; MANUBRIUM of an
orange colour, with simple oral tentacles, which carry
capitate clusters of thread-cells at the extremity ; MAR-
GINAL TENTACLES with orange bulbs and a dark ocellus
at the base of each.

WHEN finely grown, B. ra/nosa attains a height of 3 in-
ches, and presents a very tree-like appearance. In large
specimens the main stem is very thick and coarse, and the
branching luxuriant and irregular. The habit, as noted
by Mr. Alder, is not unlike that of Halecium. The lower
and larger branches are compound, like the stem, and
often much ramified. The polypiferous ramules are short,
and terminate in a very decided cup, within which the
polypite is almost concealed when retracted. This cup is

110 ATRACTYLID^;.

very frail, and soon disappears after the death of the
polypite.

The gonozooids, which are produced in great numbers,
undergo remarkable changes after their liberation. These
consist in the development of additional tentacles and
ocelli on the marginal bulbs, until the number reaches 6
or 8 in each cluster, and in the dichotomous division and
subdivision of the oral appendages. When fully matured,
they are probably identical with the B. Britannica of
Forbes's monograph.

The changes in the zooid subsequent to its detachment
have been observed by Wright in this species, and by A.
Agassiz in the American B. superciliaris. We learn from
the latter author that the second sets of tentacles are " de-
veloped in pairs, one tentacle on each side of those of
the first set," and the development proceeds in this order
until the number is complete.

In its first stage the gonozooid of B, ramosa is the Me-
dusa ocilia of Dalyell.

Hab. On shells and stones and on other zoophytes :
Scotland, on Virgularia mirabitis (Dalyell) : Queensferry,
Firth of Forth (T. S. Wright) : Oban Bay, in about 15
fathoms, very fine; dredged in Torbay (T. H.) : from the
deep-water fishing-boats, Northumberland, fine (J. A.) .

[Ostend, Van Ben.]

2. B. FRUTICOSA, Allman.

BOUGAINVILLIA FRUTICOSA, Allman, Notes on the Hydroida, Ann. N. H. for

July 1864.
EUDENDRIUM RAMOS™, Allman, Proc. Hoy. Soc. Ed. Dee. 6th, 1858.

ZOOPHYTE rising to the height of about 2 inches, much
branched; MAIN STEMS composed of aggregated tubes;
branches subalternate, the polypary of the smaller
branches slightly corrugated transversely; POLYPITES

BOUGAINVILLIA MUSCUS. Ill

in extreme extension nearly cylindrical, protected at the
base by a membranous corrugated cup, into which about
a third of the body is withdrawn when contracted; GO-
NOPHORES pyriform, on distinct peduncles, invested by
a delicate cliitinous capsule, springing from the upper-
side of the ramules, along which they range almost from
end to end.

GONOZOOID. — UMBRELLA (at the time of liberation) deep
bell-shaped, with a well-developed velum, measuring
about ^Q inch across its base ; MANUBRIUM subcylindrical,
somewhat dilated at its base, of moderate size ; RADIA-
TING CANALS terminating in bulbs, containing red pig-
ment-granules, at the root of every tentacle a black
eye-speck.

THE foregoing description is based on Prof. Allman's
papers. I have not had the opportunity of examining
this species, which differs very slightly from the B. ramosa.

The following are the distinctive points : — The polypite
of B. fruticosa when extended is of a more cylindrical and
slender form ; the membranous cup is smaller, covering
only about one-third of the body, whereas in B. ramosa it
almost entirely conceals the polypite during extreme con-
traction; and the reproductive buds are borne along the
whole of the upper surface of the ramules, instead of
occurring in pairs or small groups a little behind the free
extremity. The goiiozooids of the two forms seem to be
identical.

Hub. Growing in abundance on a piece of floating tim-
ber in the mouth of the Kenmare River, co. Kerry (G. J. A.) .

3. B. MUSCUS, Allmau.

PERIGONIMUS MUSCUS, Allman, Ann. N. H. for Jan. 1863.
BOUGAINVILLIA MUSCUS, Allman, Ann. N. H. for May 1864.

STEMS about half an inch in height , simple , springing at hi-

112 ATEACTYLIDyE.

tervals from the creeping stolon, find sending off short
branches, which are for the most part without further
ramification ; POLYPARY light brown, slightly corrugated,
with a well-marked cup-like dilatation at the base of the
polypite ; POLYPITES light reddish brown, with about 1 6
tentacula held, in extension, alternately elevated and
depressed; GONOPHORES borne on a rather long pe-
duncle, and springing from the branches a little behind
the polypite.

GONOZOOID. — UMBRELLA (at the time of liberation) dome-
shaped ; MANUBRIUM extending to about a third of the
depth of the umbrella.

THE free zooid is in all points undistinguishable from that
of B. ramosa. The present species is known by its " small
size and general habit, its more simple ramification, and
the fact that its stems consist of a single tube, instead of
being composed of numerous tubes coalesced into a dense
bundle." (Allman.}

Hub. In a rock-pool, Torquay, where it occurred abun-
dantly, creeping over the bottom in small moss-like tufts

(j. a A.).

I have met with a form in various localities which is
somewhat intermediate between this species and B. ramosa
(Plate XIX. fig. 3). It is of small size, not exceeding an
inch in height ; the main stem is compound towards the
base, but still slender as compared with that of the latter
species. The ramification is simple, the branchlets being
regularly alternate and approximate. The colour is a
light yellowish brown, and the polypary has the appear-
ance of being sanded over. The main branches are less
distant than in B. ramosa and are not compound, and the
whole habit is simpler and more delicate. The composite
portion of the stem is slender, and does not extend far.
It is made up of very delicate tubules.

Long fusiform bodies, supported on separate ramuli,

EOUGAINVILLIA MUSCUS.

113

are commonly met with on this variety, the significance of
which I have not determined with certainty, but which
are probably the nests of some parasitic larva, such as has
been observed on Hydr actinia and Syncoryne. Van Bene-
den has represented a similar structure on a zoophyte
which he refers to his Eudendrium ramosum (Mem. sur les
Tubulaires, pi. iv. fig. 2), but which, judging from his
figure of the gonophores, must be a distinct species
(woodcut, fig. 11). Possibly this may be identical with

Fig. 11.

my variety, which I have never found with its repro-
ductive bodies. This point must be left for future
settlement.

TUBULARIID^E.

Family XI. — Tubulariidae.

POLYPITES flask-shaped, with two sets of filiform tentacula,
one oral, the other placed near the base of the body,

Genus TUBULARIA, Linnceus (in part).
Der. From tubulus, a little tube.

PARYPHA, Agassiz, N. H. U. S. iv. 342 (for some of the species).
THAMNOCNIDIA, Agassiz, N. H. U. S. iv. 342 (ditto).

GENERIC CHARACTER. — Stems simple or branched, rooted
by a filiform stolon, the whole invested by a polypary ; poly-
pites flask-shaped, with filiform tentacles disposed in two
verticils — the oral short and surrounding a conical pro-
boscis, the aboral long and forming a circle near the base
of the body ; gonophores borne on peduncles springing from
the body of the polypite between the two circles of tentacles,
containing fixed sporosacs.

THE polypites of this genus are richly coloured with va-
rious shades of red, and present the appearance of bright
flowers on erect and slender stems.

The reproductive buds never become detached; but in
some cases (e. g. T. indivisa] they are furnished with an um-
brella in which the radiating and circular canals are present,
and an orifice surrounded by four tubercles, representing
the marginal tentacles. The manubrium is destitute of a
mouth. There is every preparation for independent exist-
ence up to a certain point ; but here an arrest of deve-
lopment takes place, and the bud remains enclosed in the
outer envelope, while the swimming-bell is converted into
a chamber or nursery, in which the embryo passes through
its early stages, escaping at last through the opening above.
In the development of Tubularia the plannle stage is ab-

TTJBULARIA INDIVISA. 115

sent, and the young, on issuing from the ovisac, has
already assumed the polypite form. A verticil of long
arms surrounds the base of the proboscis ; and the oral
series is either present in a rudimentary condition or
subsequently developed (Plate XX. fig. b, b) . The embryo
walks about by means of its arms, like a cuttlefish, with
its head downwards*. After a time it attaches itself by
its base, and the stem is gradually developed.

We meet with a similar mode of reproduction in a mem-
ber of the genus Coryne (C. VanBenedenii] and also in My-
riothela.

The polypites of Tubularia, at least when kept in capti-
vity, are shed at short intervals, but are soon renewed.
The prolific pulp gives origin to a succession of genera-
tions ; and the birth of each is registered by the formation
of a ring on the polypary.

1. T. INDIVISA, Linnaeus.

"TUBULAR CORALLINE, LIKE OATEN PIPES," Ellis, Corall. 31, t. xvi. fig. 6.
TITBULARIA INDIVISA, Linn. Syst. 1301 ; Lamk. An. s. Vert. (2nd ed.) ii. 125 ;

Lamx. Exp. Meth. 17 ; Daly ell, Rem. An. Scotl. i. 2, pi. i. ii.

iii. & iv. ; Lister, Phil. Trans. 1834, 366, pi. viii. fig. 1 ;

Johnst. B. Z. 48, pi. iii. figs. 1, 2 ; "Mummery, Q. J. Microscop.

Sc. for 1853, 28; T. S. Wright, Ed. N. P. Journ. (N. S.) for

Jan. 1858, 113, pi. iii. figs. 2, 3; Allman, Ann.N. H, for July

1859.

„ CALAMARIS, Pall. Blench. 81 ; Ehrcnb. Corall. roth. Meer. 71.

(?) TUBVLARIA OIGANTEA, Lamx. Expos. 17, t. Ixviii. fig. 5.

Plate XX.
STEMS clustered, simple, erect, without cumulation, narrowed

* Van Beneden's statement respecting the young of T. coronata, "elle
n'a aucun moyen de locomotion," is incorrect. The tentacles are employed
as feet. They are also used as oars, by means of which it moves freely
through the water ; and in more than one case probably the floating Tubu-
larian embryo lias been taken for a new generic form.

i 2

116 TUBULARinLE.

and twisted at the base, horn-coloured, rising to a height
of from 6 to 12 inches ; POLYPITES deep red ; oral tentacles
short and very numerous., aboral long, white, tapering,
about 40 in the adult ; GONOPHORES on branched pedun-
cles, forming large and very numerous clusters, springing
from the base of the lower tentacles; SPOROSACS with
four radiating canals and four small tubercles at their
terminations.

THE habit of T. indivisa is eminently simple, though occa-
sionally the stems divide slightly towards the lower part.
At the base the tubes are much twisted and interwoven,
and are often agglutinated together for some distance
above it.

The embryos on exclusion from the ovisac not unfre-
quently fix themselves on the stems, and develope them-
selves in this position, so as to give the appearance of
branching. I have seen whole colonies of young of all
ages grouped on the older stems.

The gonophores are developed in great profusion, and
the clusters attain a large size, hanging down on all sides
like bunches of fruit. The sporosac exhibits in great
part the structure which is characteristic of the free
sexual zooid, but continues permanently attached. At
the upper extremity there is a somewhat square opening,
with four red spots on the margin, marking the termina-
tion of the radiating canals. The spadix is red and
conspicuous. When the embryo issues from the ovisac it
has twelve of the long arms, and the oral series is just
sprouting.

The stem in T. indivisa is traversed by a system of lon-
gitudinal canals in which the circulation of the nutrient
fluid takes place ; these are arranged in a circle immedi-
ately within the outer wall of the ccenosarc, the central
portion being imperforate. They arc ciliated on the in-

TUBULA1UA INDIVISA. 117

terior surface, and terminate above in a single cavity at
the base of the lower tentacular verticil*.

This beautiful zoophyte has a wide range bathymetri-
cally, being found on rocks between tide-marks, and in
shallow water near shore, and also at great depths (140
fathoms, off the Mull of Galloway, Beechey] .

The T. gigantea of Lamouroux, which reaches a height of
from 12 to 15 inches, was referred by Dr. Johnston to the
present species; but Mr. Alder, who obtained it on the
Northumberland coast, was of opinion that it might prove
distinct, and certainly required further examination.

Hob, On rocks between tide-marks and in shallow water,
and on shells, stones, &c. from deep water : common and
generally distributed.

It often covers profusely the sides of rocks and the
under surface of ledges a little above low-water mark,
hanging from them in unsightly tufts when the tide is out,
but rising into sudden beauty with the return of the water,
and clothing them with all the gaiety of a garden. On the
pontoons of the great landing-stage at Liverpool it must
grow in wonderful luxuriance, and present a rare spectacle
of zoophytic beauty. I shall not soon forget the bucketful
of this zoophyte, in the finest condition, which Mr. Moore,
the able Curator of the Free Museum in that town, procured
for me from this locality.

Dr. Collingwood informs me that in February he has
taken specimens from the landing-stage " having pendent
clusters of ova two inches long." In summer, he adds,
this zoophyte " appears to offer a favourite feeding-ground
for Dendronotus arborescens." The Dingle rocks, also in
the Mersey near Liverpool, are covered, as I learn from
the same gentleman, at low-water mark and below it, with

* Dr. T. S. Wright, " Observations on Brit. Zooph.," Eel. N. P. Journ.
(N. S.) for Jan. 1858 ; Agassiz, N. H. U. S. vol. iv. L'07.

118 TUBTJLARIID^:.

a luxuriant growth of T. indivisa. " After a storm," he
writes, " I have seen this spot looking like a stubble-field,
the heads all gone, and the straw-like tubes only left."

Lieut. Thomas tells us, in the valuable notes which are
published in the Supplement to Johnston's ' History/ that
" on the oozy bottom which lies outside a line drawn be-
tween Flamborough Head and the Staples " it grows to a
very large size. Prof. Forbes found it in Rothsay Bay,
flourishing, as it seemed, "upright on a muddy ground
like a flower, fixed by the tapering root-like termination
of its horny case." In Cornwall, according to Couch, it
ranges in height from 2 to 14 inches. Dr. Perceval
Wright has found it in remarkable beauty off the west
coast of Ireland. Guernsey (A. M. N.).

[Tromso and the North Cape in 30 fathoms, and Bergen
(Sars): Greenland (Morch) : Bay of Biscay (Beltremieux) .]

2. T. LARYNX, Ellis and Solander.

"TuBULous CORALLINE WRINKLED LIKE THE WINDPIPE," Ellis, Corall. 30,

fc. xvi. fig. b.
TUBULARIA MUSCOIDES, Pattas (not. Linn.), Blench. 82.

„ LARYNX, Ellis and Solander, 31 ; Lamk. An. s. V. (2nd ed.) 126 ;

Johnst. B. Z. 51, pi. iii. fig. 3, and pi. v. figs. 3, 4 ; Daly ell, Kern.

An. Scotl. i. 42, pi. v.
EUDENDRIUM BitYOiDEs, Ehrenb. Cor. roth. Meer. 72.

Plate XXI. fig. 1.

STEMS clustered, simple or slightly branched, slender, pel-
lucid, pale horn-coloured, ringed at pretty regular in-
tervals; POLYPITES small, light red, with white ten-
tacles; GONOPHORES clustered on short peduncles, oval,
of a purplish-red colour.

Height from ^ an inch to 1^ inch.

T. LARYNX is of humble growth, much smaller than the next
species, and more regularly ringed. Annulated spaces

TUBULARIA CO11ONATA. 119

occur at intervals throughout the length of its stems, which
are of very thin papyraceous texture. It is sometimes
simple, but often irregularly and fantastically branched,
the branches being short and given off at various angles.
The polypite is very small in comparison with that of T.
coronata, but brilliant as others of its tribe, " equal in rich-
ness of colour to the Guernsey Lily," according to Ellis ;
and the gonophores are borne in shortly stalked clusters.

The tubes of T. larynx are on the whole less slender
than those of T. coronata, but its delicate little tufts con-
trast strongly with the tall complicated masses of the latter
species.

Hob. Common between tide-marks, and ranging to deep
water. " Near the opening of the Thames, adhering to
other marine bodies and often to the bottoms of ships ''
(Ellis) : from brackish water to 50 fathoms, on the east
coast, Scotland (Lieut. Thomas) : on stones between tide-
marks, South Devon, common (T. H.): Belfast Lough
(W. Thompson) : &c. &c.

[Mediterranean (Pallas) : Mouth of the Elbe (Kirchen-
pauer) ; Grand Manan (Stimpson).]

3. T. CORONATA, Abildgaard.

TUBULAUIA CORONATA, Abildgaard, Zool. Dan. (Milllcr), iv. 25, pi. cxli. figs.
1-5 ; Van Beneden, Memoire sur les Tubul. 49, pi. i. figs. 7-19 ;
Allman, Proc. Roy. Soc. Edinb. Session 1857-58.
„ LAKYNX, var. j3, Johnston. B. Z. (1st. edit.) 116.
„ GRACILIS, Harvey, Proc. Zool. Soc. no. xli. 54 ; Johnston, B. Z.
(2nd edit.) 52, pi. iv. figs. 3-5; Aider, North, and Durh.
Cat. in Trans. Tynes. F. C. iii. 107.

Plate XXI. fig. 2.

STEMS clustered, very slender, irregularly branched, of a
light straw-colour, smooth or somewhat wrinkled, with
occasional ringed spaces; POLYPITES larye, bright orange-

120

red ; GONOPHORES on much-branched peduncles, forming
large clusters, oval, with 4 small tubercles at the upper
extremity when mature.
Height 3 to 3£ inches.

THIS species grows in complicated masses formed of very
slender, light-coloured, interlacing tubes. The stems are
often much and irregularly branched, especially towards
the lower extremity. They are for the most part perfectly
smooth; but here and there a few distinct annulations
occur, and there is sometimes a good deal of obscure
wrinkling. The polypites are large and handsome, and the
long branched clusters of gonophores with their red centres
form a conspicuous feature.

This species has been fully investigated by Van Beneden*.
He states that the young, on exclusion from the gono-
phore, has usually twelve long arms, but he has observed
as few as six. The oral tentacles, in the cases that came
under his observation, were not developed until some time
after the embryo had made its escape. It appears, how-
ever, from the observations of Sars, that they are sometimes
present in a rudimentary state at the period of liberation.
Indeed the embryos seem to be excluded in very various
stages of development. The gonophores contain simple
sporosacs with four inconspicuous tubercles at the summit.

The T. gracilis of Harvey is probably identical with the
present species ; but his description leaves some room for
doubt.

Hob. Generally in deep water. Shetland ( J. G. Jeifreys) :
Northumbei'land, " on corallines and other marine sub-
stances, generally on a muddy bottom, in the coralline zone
and deep water" (J. A.): Lytham, Lancashire, in great
profusion, cast ashore in large compact masses (T. H.).

* Faune littor. cle Belgique, Polypes, 186(3, p. 110. pi. iy.

TUBULARIA SIMPLEX. 121

[Belgium (Van. Beu.) : mouth of the Elbe (Kirchen-
pauer) : Denmark (Abildgaard) : Sars records the occur-
rence of a Tubularia at Messina under the name of T.
larynx, which he identifies with the T. coronata of Van
Beneden. He states that the same species is common in
the North Sea.]

4. T. SIMPLEX, Alder.

TUBULARIA DUMORTIERII, Johnst. B. Z. 50 ; Alder, Trans. Tynes. F. C. iii. 106.
,, SIMPLEX, Alder, Supp. North. Cat. in Trans. Tyncs. F. C. v. 232,
pi. viii. figs. 3, 4.

Plate XXII. fig. 1.

STEM slender, smooth, unbranched, without cumulations,
generally a little angulated at intervals and tapering to-
wards the bottom, horn -coloured, usually solitary and
attached by a short creeping base; POLYPITE slender,
rose-coloured; tentacles whitish, the oral biserial, shorter
and less numerous than in T. indivisa ; the aboral 20-24,
moderately long.

Height 2 to 2^ inches.

THE tubes of this species are exceedingly slender, and the
angulatioii seems to be a pretty constant character. The
smaller size and the solitary habit distinguish it from T.
indivisa. When living, the stems appear orange or scarlet,
from the contained coenosarc.

Dr. Johnston has given a very accurate description of
this form, but referred it to the T. Dumortierii of Van
Beneden, from which it differs widely. He says that the
gonophores are spherical and shortly stalked.

Hab. On shells and other marine bodies from deep water,
Cullercoats (J. A.) : Berwick Bay (Dr. Johnston) : Oban,
on stone (T. H.).

122 TUBULARinXE.

5. T. BELLIS, Allman.

" Notes on the Hydroida," Ann. N. H. for January 1863.

Plate XXI. fig. 3.

STEMS short, sparingly branched, from | to 1 inch in
height, pretty regularly marked by distinct annulations,
which extend to the creeping stolon ; CGENOSARC orange,
deepening in tint towards the base, expanding into a
collar immediately below the polypites ; POLYPITE very
large, measuring, in full-sized specimens, about 5 lines
from tip to tip of the extended tentacles, body scarlet ;
GONOPHORES oval, on short, erect, branched peduncles ;
each gonosac with 4 well-marked tentaculoid tubercles on
Us summit ; the peduncles and spadix scarlet.

" A BEAUTIFUL little zoophyte, conspicuous by the bright
colour and large size of its polypes." (Allman). The an-
nulatiou, which extends pretty uniformly throughout the
stem, is remarkably Avell-defmed.

Hab. " Attached to the bottom of rock-pools at extreme
low-water spring-tides, Shetland" (G. J. A.).

6. T. ATTENUATA, Allman.

"Notes on the Hydroida," Ann. N. H. for July 1864.

STEM 3 or 4 inches high, slender, obscurely corrugated, of a
light straw-colour, very irregularly branched, with the
branches given off at a wide angle ; POLYPITE supported
on a collar-like expansion of the coenosarc, the oral ten-
tacles about one-third as long as the aboral, the body
deep vermilion between the two tentacular verticils, and
thence becoming paler towards the enlarged base ; GO-
NOPHORES (male) on short, erect, branched peduncles,
usually 5-8 in a cluster ; tentacular appendages long.

" T. ATTENUATA is a deep-water species. * * * It differs

• ECTOPLEUIIA. 123

from T. coronata chiefly iu its more diffuse habit and the
short erect peduncles of its clusters of gonophores ; while
from the T. simplex of Alder it is easily distinguished by
its branched hydrocaulus [stem] and the greater length
of its distal [oral] tentacles." (Allman.}

Hab. Firth of Forth, from about 15 fathoms ; Shetland
seas, from about 50 fathoms (G. J. A.).

7. T. HUMILIS, Allman.

" Notes on the Hydroida," Ann. N. H. for July 1864.

STEMS about 1 inch high, simple or sparingly branched,
springing at distinct intervals from the stolon; POLY-
PARY light yellow, with nearly obsolete transverse corru-
gations; POLYPITES rather small, scarlet, supported on
collar-like expansions of the coenosarc; oral tentacles
about 15, aboral 20 ; GONOPHORES (male) borne on very
short branching peduncles, and forming erect scarlet clus-
ters, usually about three in each cluster ; summit of gono-
sac with three rather large tentaculiform tubercles.

" IT resembles T. bellis in its mode of growth and in the
shortness of its hydrocaulus [stem] , but is at once distin-
guished from this species by the absence of distinct aimu-
latiou, and by the smaller size and less appressed form of
the polypite." (Allman.}

Hab. " On rocks close to the level of low-water spring-
tides, near the mouth of Kinsale Harbour" (G. J. A.).

Genus ECTOPLEURA, Agassiz.

Der. eKTos, without (outside), and TrXevpa, a rib.
TUBULARU (in part).

GENERIC CHARACTER. — Stems Jistular, simple or branched,

TUBULARIID^E.

rooted by a filiform stolon, the whole clothed by a polypary ;
polypites flask-shaped, with filiform tentacles in two verticils
— the oral short, surrounding a conical proboscis, the aboral
long, near the base of the body ; gonophores developed in
clusters on the body of the polypite between the circles of
tentacles, containing free medusiform zooids.

Gonozooid : Umbrella (at the time of liberation] nearly
spherical (slightly flattened at the two poles) , traversed by
prominent longitudinal ribs formed of series of thread-cells ;
manubrium with a simple mouth, shorter than the bell;
radiating canals 4 ; marginal tentacles 4, without ocelli at
the base.

E. DUMORTIERII, Van Bencden.

TUBULARIA DUMORTJEUII, Van Bcneden, Mem. sur les Tubul. f>0, pi. ii. ;

Johnston, B. Z. pi. vii. figs. 1, 2 (not the species described in

the text).
ECTOPLEURA DUMORTIERII, Agassiz, N. H. U. S. iv. 342.

Plate XXI. fig. 4.

STEMS about half an inch in height, scattered, simple (or
occasionally very slightly branched), slender, of a pale
horn-colour, attenuated and annulated at the base;
POLYPITES proportionally large, rose-coloured ; oral ten-
tacles short, in two series, numbering about 24 ; lower
tentacles about 30, of moderate length; GONOPHORES
spherical, borne on short, branched peduncles.

GrONozooiD. — UMBRELLA (at the time of liberation) melon-
shaped, traversed by eight longitudinal ribs ; MANUBRIUM
reddish; MARGINAL TENTACLES set at intervals with clus-
ters of thread-cells.

THE Tubularia Dumortierii of Johnston is not the zoophyte
that had been previously described by Van Beneden under
this name, but another species, which has been distinguished
and characterized by Alder as T. simplex.

Prof. Wyville Thomson has recorded the occurrence of

CORYMORPHA. 125

the Belgian zoophyte in Belfast Bay; but specimens of the
dried polypary from this locality, which he has kindly sent
me, are much stouter and of coarser texture than any ex-
amples I have seen of E. Dumortierii, and, I believe, must
be referred to some other species. A single stem with its
polypite, attached to a piece of drift-wood which I obtained
in the Isle of Man, cast ashore on the magnificent shingle-
beach at the Point of Ayr, is the only British specimen
that I know of. I have had the opportunity of comparing
it with specimens of E. Dumortierii supplied by Van Be-
nedeii, and have assured myself of their identity.

The present form is of small size and great delicacy of
habit, and the stems are developed singly and not in clus-
ters. The polypary is of a light yellowish horn-colour and
transparent. It is slightly annulated towards the base of
the stem, which, in my specimen, tapers off very finely, and
is attached to a short creeping fibre ; indeed the tube gra-
dually expands upwards from the point of attachment to
the terminal aperture. Here and there in the course of
the stem there occurs a more or less perfect ring.

The polypite is large for so diminutive and delicate a
species, and, like most of the tribe, is of a reddish colour.

Hob. On drift-wood cast ashore at the Point of Ayr, Isle
of Man (T. H.).

[Ostend, abundant on Flustra, the carapace of crabs,
&c. (Van Beneden).]

Genus CORYMORPHA, Sars (in part).

Der. Kopvvr] (C'orync), a club, and (Jtoptyi), form.

GENERIC CHARACTER. — Polypite solitary, borne on a
simple stem, which terminates in a conical base and is invested

120 TUBULAKIID^E.

by a delicate membranous sheath ; flask-shaped, with two
sets of filiform tentacles — the oral short, in several verticils
placed close together and surrounding a prominent probos-
cis, the aboral longer, in a single series near the base of
the body ; gonozooids on branched peduncles, borne on the
body of the polypite at the base of the lower tentacles, free
and medusiform when mature.

Gonozooid : Umbrella (at the time of liberation] nearly
globular ; manubrium with a simple mouth ; radiating canals
4<, terminating in four marginal bulbs, from one of which,
in some cases, a single tentacle is developed, while in others
each bulb bears a tentacle.

THE Steenstrupia of Forbes is founded on the free zooid
of this genus.

Corymorpha is distinguished by a number of remarkable
characters. Its solitary habit it shares with only two
Hydroid genera beside (Myriothela and Hydra}. The
membranous sheath which invests the coenosarc is a modi-
fication of the more usual polypary ; while the free basal
extremity, with its appendages, adapted to root the zoo-
phyte in the sand, is a unique peculiarity. The gono-
zooids, like those of Clavatella, are not contained in a pro-
tective sac (ectotheca) , but are naked throughout the course
of their development.

Schmidt has constituted the genus Amalthaa for two or
three species in which each of the four bulbs on the margin
of the umbrella gives origin to a fully developed tentacle.
In all other points they seem to agree with Sars's genus
Corymorpha ; and I cannot allow that a mere difference in
the number of arms, unaccompanied by any other structural
peculiarity, is a sufficient ground for detaching them from
it. I have therefore made the diagnosis of the present
genus broad enough to include them.

CORYMORPHA NTITANS. 127

1. C. NUTANS, Sars.

COUYMORPHA NUTANS, Sars, ' Beskrivclser ' &c. 7, pi. i. fig- 3; Forbes Sf Good-
sir, Ann. N. H. for 1840, (1st ser.) v. 310; Johnston, B. Z.
54, pi. vii. figs. 3-6 ; Hodge, Trans. Tynes. F, C. v. 80, pi. ii.
figs. 1-10 ; Alhnan, Ann. N. H. for January 1863.

Plate XXII. fig. 2.

STEM subcylindrical, tapering slightly upwards, and enlar-
ging at a short distance above the blunt, conical base, of a
pinkish colour, traversed by reddish-brown longitudinal
lines; POL YP A RY a transparent membranous tube; POLY-
PITE of a pink colour ; oral tentacles very numerous (about
80), delicate, very contractile, arranged in several alter-
nate series ; aboral tentacles about 30, white, long, and
tapering.

GONOZOOIDS naked, borne in clusters on the extremities of
the branched stalks ; UMBRELLA (at the time of libera-
tion) almost globular, slightly narrowed towards the
aperture, continued above into a short conical apex tra-
versed by a canal, with a broad velum and of a pale
yellowish-brown colour; MANUBRIUM large, subcylin-
drical ; MARGINAL BULBS reddish- brown, with carmine-
coloured spots, — one, larger than the rest, bearing a single
tentacle, the others without tentacles ; the tentacle very
extensile, beaded with spherical clusters of thread-cells,
of which the terminal one is the largest.

Size, at the time of liberation, about -^ of an inch in
diameter.

THE lined appearance of the stem in Corymorpha is due to
the presence of a number of longitudinal canals excavated
in its substance, through which the nutrient fluid circu-
lates. The arrangement of these canals is much the same
as that met with in Tubularia.

The lower tentacles possess little contractility, differ-

128 TUBTJLAHIIDTE.

ing in this respect from the oral series, which act as pur-
veyors to the mouth. The number can only be stated ap-
proximately, as it varies with age. The arms are pure
white; while the proboscis is pink, and the clusters of
gonozooids orange-coloured. Forbes says of the Cory-
morpha, that " when placed in a vessel of sea- water it pre-
sented the appearance of a beautiful flower. Its head
gracefully nodded (whence the appropriate specific appella-
tion given it by Sars), bending the upper part of its stem.
It waved its long tentacles to and fro at pleasure, but
seemed to have no power of contracting them. Its beauty
excited the admiration of all who saw it."

The membranous sheath, according to Allman, invests
the entire stem, lying close to it on the upper part, and
forming a loose corrugated sac below. Forbes and Goodsir
represent it as deciduous, and state that it disappears in
the adult, with the exception of the part that envelopes
the base. In the specimens which I have examined it
covered a large portion of the stem, but did not extend so
far as the base of the polypite. It probably varies with age.

A number of tubular and extensile appendages are given
off from the lower part of the stem, which are free pro-
longations of the longitudinal canals. I have little doubt
that they are organs of attachment, as I have always found
them immersed in the sand, and they are generally thickly
coated with it. But, besides these larger processes, the
whole of the conical base gives off an immense number of
extremely delicate threads, often of very considerable
length, which form an entangled mass of interlacing fibres.
These are very adhesive ; and spreading in all directions
through the sand, they gather the particles about them and
form a complicated and tenacious root, by which the zoo-
phyte is securely fixed in its place. If the sand be carefully
removed, the extremity is seen to be completely villous.

CORYMORPHA NUTANS. 129

Sarshas accurately described this portion of the structure,
and has remarked on the difficulty of detaching the Cory-
morpha from its site. "When taken up, it has usually a
bulb of sand at its base, which is held together by the ad-
hesive threads.

Allman has seen a specimen, when in confinement and free
from sand, attach itself to the bottom of the vessel in which
it was kept, by means of a multitude of fine tubular fila-
ments, which formed an entangled web-like tissue, and
which were ultimately invested with a delicate polypary.

We have here a most interesting modification of the
hydrorhiza, adapting it to the pecidiar locality in which
the Corymorpha lives. The ordinary stolonic network,
which is suitable only for a firm base, gives place to a mul-
titude of long hair-like adhesive rootlets, which fix the
zoophyte securely, even in the yielding sand.

The gonozooid seems to undergo little change after
liberation, merely increasing in size.

Hub. Bay of Stromness, Orkneys, in 10 fathoms (Forbes
and Goodsir) : Shetland (Forbes) : Fowey, Cornwall* : Isle
of Man (J. A.) : Seaham Harbour, Durham, not uncom-
mon in from 6-12 fathoms (G. Hodge) : Firth of Forth in
about 14 fathoms (G. J. A.).

Corymorpha nutans varies much in size according to the
locality. Specimens from the far north reach a height of
3£ or 4^ inches. The Durham examples are smaller;
while the Cornish specimen is still more diminutive.

[Near Bergen, Norway, in 30-40 fathoms (Sars) : Grand
Manan, on a sandy bottom in from 4-15 fathoms, abun-
dant : off West Quoddy Head one hundred, or more, were
taken at a single haul of the dredge (Stimpson)t-]

* Mr. Peach has also obtained two other specimens in Fowey Harbour.

t Sars, in a recent paper on Corymorpha, has described several new and
nearly allied spcciea. Steenstrup has published a tropical form procured
from Rio Janeiro.

130 TUBTJLARIID^.

2. C. NANA, Alder.

HYDRACTINIA, Johnston, B. Z. 463, woodcut, fig. 79 a.

? (Alderi) Gray, Cat. Brit. Mus. Eadiata, 61.

CORYMORPHA NANA, Alder, North, and Durh. Cat. Trans. Tynes. F. C. iii. 108,
pi. ix. fig. 7, 8 ; Supplem. Trans. Tynes. F. C. v. 233, pi. xi.

Plate XXII. fig. 3.

STEM elongated, subcylindrical, transparent, white or yel-
lowish, with opake ivhite lines, bearing towards the lower
part of it a number of extensile tubular processes ; poly-
pary a transparent filmy sheath, ending at the base in a
gelatinous mass (?) by 'which the animal is att ache d ; POLY-
PITES yellowish ; oral tentacles about 16-18 in two imper-
fect rows, aboral tentacles 15-20.

GONOZOOID naked, sessile, urn- or bell-shaped ; UMBRELLA
(at the time of liberation) rather deep, semiglobose,
transparent white ; MANUBRITJM rather long and thick ;
RADIATING CANALS yellowish, three of them ending in a
yellow bulb on the margin, the fourth produced into a
club-shaped (?) tentacle.

Height of zoophyte | to f inch.

" COKYMORPHA NANA is a very active animal, constantly
changing its form and the proportions of its parts. * * *
In many of its states it bears a considerable resemblance
to C. nutans, from which, however, it differs, not only in
the diminutive size, but in the gonophores being sessile
(not pedunculated or branched as in the latter), and large
in proportion to the size of the animal. The medusoicl
differs from that of C. nutans in having the umbrella
rounded at the top ; in other respects it is very similar."
(Alder.} Alder seems to have described the single tentacle
of the gonozooid when in a contracted condition. It pro-
bably resembles in structure that of C. nutans.

He states that this species produces dissimilar repro-
ductive bodies. On one polypite they were developed into

131

free zooids ; on another they presented a very different
appearance, having tuberculated lobes on the upper part,
and remaining attached during the whole time that the
polypite continued to live, about ten days. Mr. Alder had
little doubt of their continuing permanently fixed. He
conjectures that the distinction is a sexual one ; but we
must wait for further observations before we can decide
upon its significance. We have, I believe, no analogous
fact on record.

Family XII. — Pennariidae.

POLYPITES with two sets of tentacles — one oral and capitate,
the other aboral and filiform.

Genus VORTICLAVA, Alder.

GENERIC CHARACTER. — Polypites borne on simple stems,
developed at intervals on a creeping filiform stolon, the whole
ccenosarc clothed with a very delicate film-like polypary (?);
tentacles in two dissimilar verticils — the oral short and capi-
tate, the aboral long and filiform.

Reproduction unknown.

THIS genus was founded by Alder after the examination of
a single specimen, which had probably not attained its full
development. He describes the polypite as solitary and
naked; and Wright assigns the same characters to his V.
proteus. In both cases, however, I believe, the individuals
observed were merely primary polypites, and would have
given origin in time to a creeping stolon on which other po-
lypites would have been developed. I have a specimen of
Vorticlava (obtained at Salcombe in South Devon) which

K.2

132 PEXNARIID.E.

consists of two polypites united by a short adherent base,
one of them apparently fully grown, the
other of small size and with only four
knob-like tentacles round the upper ex-
tremity (woodcut, fig. 12). It may per-
haps be referable to the V. proteus ; at
any rate it shows what the perfect form
of the genus is.

The type of the family Pennariidce is the Pennaria of
Goldfuss, founded on the Sertularia pennaria of Cavolinr's
admirable work (a form that has not occurred on our
shores) .

1. V. HUM ins, Alder.

••Cut. of Zooph. of North, and Durh.," Trans. Trues. F. C. iii. 10U.pl. lii.
figs. 1-4.

Plate XXIII. fig. 1.

STEM nearly cylindrical, tapering slightly towards the
upper part ; POLYPITE wrhite, semitransparent ; oral ten-
tacles 5, short and stout ; aboral tentacles 10, rather
stout, smooth, about three times the length of the upper.

Length of body -^ inch.

Mr. ALDER'S specimen, which lived with him for several
days, " was sluggish, holding itself always in a curved po-
sition, as represented in the figure/'' The mouth is tubular
and prominent ; the upper tentacles which surround it are
generally curved inwards; they bear a cluster of small
thread-cells on the capitula.

Hab. On Corallina officinalis in a rock-pool between tide-
marks, Cullercoats (J. A.) : Felixstowe (Busk).

ACIIARADRIA. 133

2. V. PROTEUS, T. S. Wright.

" Observations on Brit. Zooph.," Quart. Journ. Microscop. Science, iii. (N. S.)
50, pi. v. figs. 1-6.

Plate XXIII. fig. 2.

STEM, when fully extended, cylindrical and slender, capable
of great elongation and contraction, invested by a deli-
cate transparent film ; POLYPITE somewhat globular ;
capitate tentacles 5, filiform tentacles 9.

THE transparent layer which covers the body of the poly-
pite ' ' extends from the foot, where it forms a thick mass, to
a ridge which runs beneath the insertion of the lower row
of tentacles."

The zoophyte, as it occurred to Dr. Wright, was solitary,
and had the power of changing its place. But, as I have ex-
plained, his specimens were probably immature, the pri-
mary polypites of a species which is compound and fixed in
its perfect condition. It maybe identical with the Devon-
shire form to which I have referred before ; but in the
present state of our knowledge nothing can be said with
certainty of the species of Vorticlava. A glance at the
figures of V. proteus will show that it well deserves its
specific name.

Hab. On a stone in the " Fluke Hole," Firth of Forth
(T. S. W.).

Genus ACHARADRIA, T. Strethill Wright.

GENERIC CHARACTER. — Stems branched) clothed with a
chitinous pohjpary • polypites with two rows of tentacles —
the aboral long and filiform, the oral short and capitate.

Reproduction unknown.

134

Dr. WRIGHT has given us a very brief description of this
zoophyte. He does not mention or figure any creeping
base ; but probably the erect shoots are bound together
and rooted by a filiform stolon, as in other cases. " This
little Tubularian * * bears the same relation to Vorti-
clava that Tub. larynx does to Corymorplia" (Wright.}

A. LARYNX, Wright.

" Observations on Brit. Zooph.," Micr. Journ. (N. S.) iii. 50, pi. v. figs. 7, 8.

Plate XXIII. fig. 3.

STEMS sparingly branched, spirally twisted ; POLYPITES pale
orange ; oral tentacles from 2 to 8, aboral from 4 to 12.
Height about £ inch.

A. LARYNX resembles in habit Tubularia larynx.
Hob. On stones, Ilfracombe (T. S. W.).

[The following genus should have been placed amongst
the Podocorynida, p. 35.]

Genus CIONISTES, T. S. Wright.

GENERIC CHARACTER. — Polypites sessile, with a single
verticil of filiform tentacles, developed at intervals on a re-
ticulated stolon ; gonophores borne on rudimentary poly-
pites, which are columnar and without either tentacles or
clusters of thread-cells ; reproduction by means of fixed
sporosacs.

WE have but a slight account of this genus from its

CIONISTES RETICULATA. 135

author; and it is difficult to decide upon its true position.
It seems to have most affinity with the Podocorynida, and
maybe referred provisionally to that family. I had in-
tended originally to place it amongst the Atractylida>,
and am now obliged to insert it out of its proper
connexion.

C. RETICULATA; T. S. Wright.

Ann. N. H. for August 1861, (ser. 3) viii. 123, woodcut, fig. 1.

POLYPITES (alimentary) minute, white, with short tentacles,
borne at distant intervals on a close network of flattened
tubes; GONOPHORES (male) oval, somewhat pointed above,
numerous, developed on imperfect polypites, which are
thickened towards the apex.

ALL our knowledge of this species is derived from a very
brief description by Dr. Strethill Wright, which is not
minute enough to be of much value.

Hab. On an old shell, Granton, near Edinburgh

(T. S.W.).

Fig. 13.

Podoeorync areolata (Alder).

136

CAM PAN ULAHIID^E.

Campanularia angulata, Hincks.

CAMPANULA R1JD.E. 137

Suborder II.— THECAPHORA.

SERTULAKJ.NA, Ehrenbcrg, Coral!, des roth. Meer. 73; Johnston, Brit. Zoopb.

i. 57.

SERTULAKIAD.E, Huxley, Oceanic Hydrozoa, 21.
SERTULARLE, Agassiz, Nat. Hist. U. S. iv. 348.
SKEXOTOKA, J. V. Cams, Handbuch der Zoologie, ii. 558.

Family I. — Campanulariidse.

HYDROTHEC.E terminal, pedicellate, campanulate ; POLY-
PITES with a large, trumpet-shaped proboscis.

THIS family is preeminent for delicate beauty and
graceful habit. It includes a very considerable number
of British species, of which some are deep-water forms ;
but a large proportion are found either between tide-
marks or at no great distance from the shore.

If we imagine minute crystalline chalices, creuated or
plain round the margin and mounted on slender pedicels,
twisted spirally or delicately ringed, which are all united
and bound to the body on which they grow by the finest
network of tubes, we have the form which the polypary
assumes in one section of this exquisite group. In an-
other the species are arborescent and sometimes of con-
siderable size, their tree-like tufts presenting the most
lovely shapes, the branches laden with the hyaline calycles
(variously formed and adorned) and with the vase-like cap-
sules, and the whole structure exhibiting an indescribable
delicacy of texture and gracefulness of habit. In both
these sections the polypites are generally large and hand-
some ; and when the embossed tentacles are thrown out
over the margin of the little crystal dwelling, some droop-
ing downwards, others standing almost erect (like a circle

138 CAMPANTJLARIIDJE.

of guards) around the central proboscis, a prettier sight
will not often reward the naturalist.

"Delicacy, transparency, and grace pervade the entire
structure ; the spirit of beauty has thrown itself into every
curve and line : the eye rests with full satisfaction on the
little cups, so perfect is their form ; and hardly less beau-
tiful are the ringed and twisted pedicels that support
them."

In another section the calycles are curiously opercu-
lated, being surmounted by little turrets formed of con-
vergent segments, which open to allow of the passage of
the polypite, and close again as it retreats.

The polypites present few diversities. The body, when
extended, is elongate, expanding upwards, and terminating
above in a very conspicuous cup-shaped proboscis, around
which the numerous milk-white tentacles, roughened by
the whorls of thread-cells, are ranged, alternately de-
pressed and elevated.

The polypite does not extend to the bottom of the
hydrotheca, but rests on a kind of floor a short distance
from it, to which the coanosarc or common connecting-
thread is prolonged from below.

In one instance at least (Campanularia flexuosa, Hincks),
the tentacles are united towards the base by a membranous
web of extreme tenuity. The gonophores are contained
in protective cases (gonothecae), which exhibit the elegance
of form that is so characteristic of the family.

The reproductive zooids in this family present many
modifications. In some of the genera they are simple
sporosacs, in which the generative products are matured
within the capsule, being discharged at length through its
orifice. In a few cases the development of the ova is
completed within an extracapsular marsupium, which
bursts at last and liberates the planulcs. In other genera

CAMPANULARIID^. 139

we have free medusiform zooids, and these exhibit different
types of structure.

The generic groups in this family are founded for
the most part on the differences presented by the
reproductive system. In Lovenella alone are good dis-
tinctive characters supplied by the polypite and caly-
cle; in the remaining genera they must be sought al-
together in the portions of structure connected with the
propagation of the species. As these are not always
present, a practical difficulty will often encounter the
student ; he may be unable, in the first instance, to refer
his specimen to its genus, and must go through the
species of several allied genera in order to determine its
position. A similar difficulty meets the systematist, who
can only assign a provisional place to those forms the
reproductive phase of which has not been observed*. In
one or two cases I have ventured to locate such forms
conjecturally; but most of them are ranged for the time
under Campanularia, with which, so far as the trophosome
is concerned, they agree, and must be referred to their
proper place in the system as their reproductive history
is known. The number of such species is but small.
Much more numerous probably are the reproductive
zooids that have not yet been traced to the Hydroid
stock.

The Campanulariida are very widely distributed over
the globe. Many of the British forms have been obtained
on the Atlantic coast of North America, as well as a con-
siderable number of species belonging to the genera Clytia
and ObeHa which have not been found in our seas. One
or two fine species of Campanularia are described by A.
Agassiz from the Pacific side — one of them, of gigantic
size, ranging from San Francisco to Behring's Straits.
* These remarks apply to many other families.

140 CAMPANULARIIDJE.

The Campanularia volubilis (Linn.) has been observed
at the following points: — the coast of Massachusetts, the
Gulf of St. Lawrence, Iceland, the North Cape, and Shet-
land. Obelia yeniculata has been tracked along much the
same course. All the Norwegian species have, I believe,
been obtained in Great Britain.

Of the Mediterranean species, which are not numerous
so far as known to us, a large proportion occur on our
own coasts.

In Australia and New Zealand the family seems to be
well represented by forms which differ from the European.
I have described a remarkable species from Melbourne
(Hincksia, Agassiz), which has very curious decumbent
gonothecae ; and I possess a second from Australia, which
exhibits the same peculiarity.

Nowhere perhaps is Campanularian life to be met with
in greater profusion than on the floating weed of the
gulf-stream. I have seen large masses of it netted over
by the delicate white fibre of a species allied to Clytia
Johnstoni, from which rose thousands of the annulated
stalks, surmounted by the prettiest campanulate calycies.

Genus CLYTIA, Lamouroux (in part).

Der. From Clytie, one of the Oceanides.

CAMPAKULARIA (in part), Lamarck, An. s. V. (2nd ed.) ii. 129.

CLYTIA, Agassiz, N. H. TJ. S. iv. 354 ; Van Beneden, Faune Litt. de Belg.

Polypes, 165.

TROCUOPYXIS, Agassiz, N. H. U. S. iii. 46 ; iv. 354.
PLATYPYXIS, Agassiz, N. H. U. S. iv. 306, 354.
EUCOPE (in part), Gegenbaur, " Versuch eines Sjst. der Medus.," Zeitscb. f iir

wissenschaft. Zool. viii. 241 (the free zooid).
CAMPANULARIA, Allman, Ann. N. H. for May 1864.

GENERIC CHARACTER. — Stem simple or slightly branched,

CLYTIA. 141

rooted by a creeping stolon ; hydrotlieca bell-shaped, with-
out operculum ; polypites with a large trumpet-shaped pro-
boscis ; gonothecce borne on the stolon and on the stems, and
producing free medusiform zooids.

Gonozooid : Umbrella (at the time of liberation) almost
globular; manubrium short, ^-lipped; radiating canals 4 /
marginal tentacles 4, with bulbous bases, ivhich are not
ocellated ; lithocysts 8, two in each interradial space, borne
on the free margin of the umbrella.

The number of tentacles and of lithocysts increases with
age, and the shape of the umbrella undergoes considerable
change.

I FOLLOW Agassiz and Van Beneden in adopting Lamou-
roux's name of Clytia for the present section of the
Lainarckian genus Campanularia, which must be broken
up into several distinct groups. It is distinguished by its
somewhat deep-belled gonozooid Avith a comparatively
small number of arms, and with the lithocysts between the
tentacles and not upon them. The species that produce
free sexual zooids with a depressed umbrella and numer-
ous reentrant arms, and the lithocysts placed on the base
of the tentacles, must bear the name Obelia, which was
introduced by Peron and Lesueur in 1809. To the species
that are destitute of a medusiform zooid, Lamarck's old
and well-established designation, which was applied ori-
ginally to simple and branched forms alike, may be
assigned.

The Laomedea of Lamouroux and Johnston was formed
to include the branched and tree-like as distinguished
from the simple and creeping species — a division that does
not represent the natural affinities and cannot be main-
tained. In choosing between the various names that have
a claim to be retained for the new groups, I have thought

142 CAMPANULARIED^E.

it better not to apply the one which immediately suggests
to the mind this false distinction, and has become identi-
fied with the branching forms, to genera composed
either wholly or in part of simple species. I have
therefore retained Clytia, which was assigned by its
author to such species, for the first section, and Cam-
panularia for the third*.

Besides the groups just referred to, Lamarck's Cam-
panularia would embrace within its ample bounds the
Gonothyraa of Allman, while in C. syringa it includes
the type of yet another genus.

The present genus affords a striking illustration of the
changes which the sexual zooid may pass through as it
advances towards maturity. According to the observa-
tions of A. Agassizf, that of C. bicophora (which seems to
be our C. Johnstoni with an American title) loses after a
time its globular outline, and
assumes the appearance repre-
sented in the accompanying
figure (woodcut, fig. 15). The
lower portion of the bell bulges
out, the tentacles are doubled
in number, and the rudiments
of eight more are traceable on the margin. The ovaries
have also increased in size.

In its adult stage the zooid is hemispherical in form,
and measures a quarter of an inch in diameter ; it is fur-

* Allman has apportioned these names somewhat differently. He has dis-
carded Clytia on the ground that it has been less generally used by authors,
and gives Laomedea to the third group. To me, I confess, a less familiar
name seems preferable to one with which inconvenient associations are con-
nected ; and it must not be forgotten that Clytia finds a place in the two
latest works of any magnitude on the Hydroida, those of Agassiz and Van
Beneden.

t North American Acalepha5, p. 78, figs. 108-110.

CLTTIA. 113

nished with sixteen long tentacles ; and additional litho-

cysts are also developed, one on each

side of the four primary tentacles

(woodcut, fig. 16). The ovaries are

"brownish purse-like glands, extending

towards the base of the proboscis."

I have never witnessed these changes
in C. Johnstoni ; but I have found the
sporosacs present before the escape of the gonozooid, and
laden with ova shortly after; so that the reproductive
functions are discharged in the earliest as well as in the
later stages of its existence. Wright has made similar
observations, and has seen the ova developed into young
Campanularians in about a week after the escape of the
zooid from the capsule.

Agassiz is of opinion that three of Gegenbaur's species
of Eucope (E. campanulata, E> thaumantoides , and E.
affinis) are only different ages of Clytla bicophora ; and I
have little doubt that the opinion is correct.

C. JOHNSTONI, Alder.

SKRTULARIA VOLUBILIS, Ellis Sf Soland. Zoopb. 51, pi. iv. figs, e, f, E, F.
CAMPANULARIA VOLUBILIS, Johnst. B. Z. 107-108, woodcut, fig. 18; Coucli,

Corn. Faun. pt. 3. 40, t. xi. fig. 1 ; Hincks, " on Keproclue-

tion of Campanulariadoe," Ann. N. H. for July 1852, pi. iii.

fig. 5.
„ JOHNSTONI, Alder, North. &Durh. Cat. in Trans. Tynes. F. C.

v. 126, pi. iv. fig. 8 ; T. S. Wright, Ed. New Phil. Journ.

(N. S.) for April 1858 ; Allman, Proc. Boy. Soc. Ed. for

Dec. G, 1858.
EUCOPE CAMPANULATA, E. THAUMANTOIDES, E. AFFINIS (the free zooid), Gegen-

baur, Syst. d. Medus., Zeitsch. f. wissench. Zool. viii. 243,

244, pi. ix. figs. 8, 9, 10, 12, and 13.
CLYTIA BICOPHORA, Agassiz, N. H. U. S. iv. 304, pi. xxvii. figs. 8, 9 ; pi. xxir.

figs. 0-9.

Plate XXIY. fig. 1.
STEMS long, transparent, simple or slightly branched,

14 i CAMPANULARIID.E.

ringed at the base and at the top, the intermediate por-
tion generally smooth ; HYDROTHECJE deeply campanulate,
and rather large, expanding slightly above, with 10-12
strong triangular teeth round the rim ; GONOTHEC^E borne
on the creeping stolon, and occasionally on the stem,
ovate, strongly ringed transversely — the segments more
or less carinated — truncate at the top and shortly pe-
dunculate.

GONOZOOID. — UMBRELLA (at the time of liberation) globose,
perfectly transparent, with numerous thread-cells im-
bedded in its substance, and a very wide velum ; MANU-
BRIUM short, somewhat swollen towards the base, with
a 4-lipped mouth ; MARGINAL TENTACLES very extensile,
muricated, halfway between each pair a small tubercle
(rudimentary tentacle) with a lithocyst on each side
of it.

C. JOHNSTONI is one of the commonest of our British Cam-
panulariidse. The calycles are generally large and the
pedicels of great length : but there is considerable varia-
tion in these points ; on the same specimen the calycles
are often of the most various sizes. The denticulation of
the margin is strongly marked. The stems for the most
part have the middle portion smooth ; but there is some-
times a little ringing even here, and I have met with a
variety (which I do not venture to separate from C, John-
stoni) in which they are closely ringed throughout. The
capsule is more or less produced, and the rings upon it
are much more clearly denned in some specimens than in
others.

The polypite is large and handsome, with between 20
and 30 long, muricated tentacles.

C. Johnstoni is occasionally branched, and bears the
capsules on the stem. I have not seen more than one or
two branches in any case (exact copies of the original
shoot), on which a small and imperfectly formed capsule

CLYTIA JOHNSTONI. 145

was usually present. Sometimes, however, as I learn from
Dr. Strethill Wright, two or three branches spring from a
little below the polypite, and " these secondary stems in
like manner give off tertiary stems/' the capsules in such
specimens being often axillary.

The free zooid seems to have been first noticed by Van
Beneden, who has figured it in a paper entitled " Un mot
sur le Mode de Reproduction des Animaux Inferieurs/'
published in 184-7.

It is a most exquisite organism, about •£$ of an inch
in height at the time of liberation, of graceful form and
the purest transparency; its presence is indicated to the
naked eye by five opake-white dots, marking the four arms
and the manubrium. The perfectly translucent umbrella
can only be detected by the aid of a lens. The arms during
motion are curled up in several spiral coils, but are capable
of great extension. The reproductive sacs are borne on
the radiating canals as minute globular enlargements.
Each of the lithocysts on the free margin of the umbrella
contains a single spherule of carbonate of lime, which is
highly refractile. These charming little floating polypites
are cast off in immense numbers by the fixed colonies
of the Clytia, each freighted with the seed of new ge-
nerations; so that we may not wonder at the profuse
distribution of the species. M. Lacaze-Duthiers, writing
from the neighbourhood of St. Malo, says that he could
not take up any water from the sea without meeting with
some of them. He was able to observe the ciliated em-
bryo, which he describes as resembling a Paramecium in
form, and about half a millimetre long.

The Campanularia Gegenbaurii of Sars (Middelhavet's
Litt. Faun. p. 48 ; Gegenbaur, ' Generationswechsel/ pi. i.
figs. 1, 2) is perhaps a mere variety of the present species.

Hob. Extremely common from between tide-marks to

L

146 CAMPANULAUIID^E.

deep water. Like other Campannlarians it shows a pre-
dilection for the red weeds. The ribbon-like leaves of
Zostera marina are also frequently profusely covered with
it ; indeed it is generally distributed and adorns with its
crystal cups and ringed pedicels the most various marine
substances.

[Belgium ; Brittany ; Norway (Van Ben.) : coast of
France generally (Lacaze-Duthiers) : "from Grand Ma-
nan Island, at the extreme eastern coast of Maine, all
along the New England coast to Vineyard Sound, south
of Cape Cod " (Agassiz).]

Genus OBELIA, Peron fy Lesueur*.

LAOMEDEA, Larnouroux, Bulletin Philomatique, 1812.

CAMPANULARIA (in part), Lamarck, An. s. V. (2nd ed.) ii. 129.

MONOPYXIS, Ehrenberg, Corall. roth. Meer. 73.

THAUMANTIAS (in part), Forbes, Brit. Naked-eyed Medusae, 41.

EUCOPE (in part), Gegenbaur, " Syst. d. Medus.," Zeitschr. f. wissenschaft.

Zool. Tiii. 241 (the free zooid); Agassiz, N. H. U. S. iv. 351.
OBELIA, M'Crady, Gymnoph. Charleston Harb. ; Agassiz, N. II. U. S. iv. 351 ;

Allman, Ann. N. H. for May 1864.

GENERIC CHARACTER. — Stem branching, plant-like, rooted
by a creeping stolon ; hydrothecce campamilate, without
operculum ; gonothec& borne on the stems and branches ;
reproduction by free medusiform zooids.

Gonozooid : Umbrella (at the time of liberation] depressed
and disk-like ; manubrium short and quadrate ; radiating
canals 4 ; 'marginal tentacles numerous (increasing in num-
ber with age) , prolonged at the base and projecting inwards ;
lithocysts 8, two in each interradial space, borne on the in-
ner side of eight of the tentacles near the base.

M'CRADYf was the first to restore the name Obelia, con-

* "Histoire gen6rale des Meduses," Ann. du Museum, xiv. 43, 1809.
t Gymnophthalmata of Charleston Harbour, p. 94.

OBELIA. 14-7

ferred by Peron and Lesuenr at a very early date on a
supposed Medusa, which we now know to be the repro-
ductive element of a Campanularian zoophyte. Agassiz
has adopted it for one section of the species, producing
gonozooids with a shallow, disk-like umbrella; and All-
man has extended it to the whole group. In this, I have
no doubt, he is right. The character employed by
Agasssiz to distinguish his genera Eucope and Obelia
(the number of arms which the sexual zooid possesses at
the time of liberation) is barely of specific value.

The younger Agassiz insists upon the presence or ab-
sence of sporosacs at the time of liberation as an important
character, and goes so far as to separate the 0. yemculata
of Wright from that of Gosse because they differ in this
respect. To the former, which he identifies with the
Eucope diaphana of his father's great work, he assigns
the name of alternata. I feel convinced that this is a
mistaken view ; and unfortunately it is one which intro-
duces confusion and difficulty into the science by enlarging
the list of synonyms. The fact is, that the gonozooids
contained in the same capsule leave it in very various
stages of development ; this is proved by the differences
in size and the condition of the marginal tentacles at the
time of liberation*. And I have no doubt that the earlier
or later appearance of the ovaries is to be explained in the
same way : it is a variation in the degree of development,
and not a specific difference. On the free zooids of Clytia
Johnstoni Wright and myself have found ovaries with ova
directly after their escape ; Allman, on the contrary, met
with none on his specimens. A. Agassiz found them in

* Wright also mentions another diversity amongst the gonozooids of 0.
geniculata. In some the ovaries were close to the manubrium, in others
midway between the base of it and the marginal canal ("Observat. on Brif.
Zoophytes," Ed. N. P. Journ. for .Tnn. 1*.">9).

148 CAMPANULARIID^E.

the young zooid, "hardly visible, as very short narrow
lines on both sides of part of the upper half of the radia-
ting tubes "*. These observations point to variations
in the time of development, and prove that the period
at which the sporosacs appear is not a point of any special
significance.

In the present work the Eucope and Obelia of Agassiz,
embracing respectively the species with 24-armed and 1(3-
armed gonozooids, are blended in the single genus Obelia ;
and the E. alternata (A. Agassiz) is ranked as a synonym
of the well-known and widely distributed 0. geniculata
(Linnseus) .

It appears from the observations of A. Agassiz that, in
this genus, " with advancing age the Medusae lose the
habit of swimming with the proboscis uppermost, and
gradually assume the usual mode of swimming of jelly-
fishes." The arms increase greatly and, it would seem,
rapidly in number, and the sporosacs become larger and
change their form with age, differing somewhat in shape
in the two sexes.

In the Thaumantias of Forbes's Monograph several
members of this genus are included; and some of his
species are only various stages of one and the same
Obelia.

The earliest figure of the medusiform zooid with
which I am acquainted is found in Easter's ' Opuscula
Subseciva' (1762)t- He gives a very fair representa-
tion of it, and describes it as a polyp which had fallen
from the coralline " ob vehementiorem aqua infusionem."
He observed a considerable number of these detached
polyps swimming freely in the water, and fancied that in
some cases they fixed themselves again on the branches

* North American Acalepha?, p. 78. t Vol. i. p? 27, pi. v. fig. D.

O13ELIA GENICULATA. 119

from which they had dropped. His inference was, that
the polypites and the coralline were distinct organisms,
and had no essential connexion with one another.

1. O. GENICULATA, Linnseus.

" KNOTTED-THREAD CORALLINE," Ellis, Corall. 22, pi. xii. b, B.

SERTULARIA GENICULATA, Linn. Syst. 1312; Pallas, Elench. 117; Lamk. An.

s. Vert. (2nd ed.) ii. 149.
LAOMEDEA GENICULATA, Lamx. Cor. flex. 208 ; Johnst. B. Z. 103, pi. xxv. figs.

1, 2; Gossc, Devon. Coast, 84, pi. iv. (the free zooid).
CAMPAXULARIA GENICULATA, Flem. Brit. An. 548.
MONOPYXIS GENICULATA, Ehrenbcrg, Corall. roth. Meer. 73.
EUCOPE DIAPHANA, Agassis, N. H. U. S. iv. 322, pi. xxxiv. figs. 1-9*.
OBELIA GENICULATA, Allman, Ann. N. H. for May 1864.
EUCOPE ALTERNATA, A. Agassi?, North Am. Acaleph. 86.

Plate XXV. fig. 1.

STEM zigzag, sometimes sparingly branched, jointed at
each of the flexures, and thickened immediately below
them, so as to form a series of projections or rests, from
which the pedicels rise; HYDROTHEC^E somewhat ob-
conical, rather short, the length slightly exceeding the
width, with a plain margin, borne on short, annulated
stalks (rings 4-6), which are suberect and taper slightly
upwards ; GONOTHEO/E axillary, urn-shaped, attached by
a short ringed stalk (3-4 rings).

GONOZOOID. — UMBRELLA (at the time of liberation) very
shallow, discoid, colourless, presenting a reticulated ap-
pearance ; MARGINAL TENTACLES 24 ; SPOROSACS OVal.

THIS species is distinguished from all its British congeners
by the peculiar structure of the stem. It is divided by
simple joints into a number of short and rather stout in-

* The Thaumantias diaphana described by Agassiz in the Mem. Am. Acad.
iv. p. 300, is, according to A. Agassiz, the sexual zooid of another species, and
was wrongly referred by him to the present species in the ' Contributions to
the Nat, Hist, of the United States.'

150

ternodes, which are elbowed above on alternate sides, so
that a kind of bracket is formed for the support of the
calycles. The capsules are of a most elegant form, resem-
bling, as Dr. Johnston has remarked, a Greek vase or urn ;
they are elongate, and taper off gradually from the flat-
tened top to the base, becoming very slender below. From
the summit rises a short tubular orifice. They very gene-
rally project at right angles to the plane in which the
calycles lie*; at times, however, they seem to be ap-
pressed to the stem. They contain a large number of
gonophores. The gonozooids are beautiful objects, and
very lively in their movements; they are liberated in
great numbers, and are excluded in very various stages of
development : — some small, with the arms stunted ; others
much larger, with the arms of considerable length.

The shallow swimming-bell is often reverted, the mauu-
brium hanging below the convex surface, and the tentacles
drooping in graceful curves from, the margin. In this
state they might serve as the model for a vase. The
lithocysts contain a refractile spherule, and stand out
prominently on the basal portion of the tentacle. I
have noticed a little orange-colour at the base of the
manubrium.

There are two marked forms of this species : — one deli-
cate, of a pure whiteness and rather humble growth ; the
other much larger and coarser in habit, and less strongly
zigzagged. I have seen specimens in which the scale of
all the parts was much smaller than in the common form.
A dense forest of this variety covers a broad frond of sea-
weed in my collection, bearing the elegant capsules in
great profusion; they are developed 011 the creeping

* Agassiz has pointed this out in his account of the American Eucope
(liaphana, a species which I cannot hesitate to identify with the present
(3i.II. U. S. v,,l. iv. p. 324).

OBELIA GELATINOSA. 151

stolon, as well as ill the axils, and are in some cases
borne on rather long peduncles. The number of gono-
zooids liberated from a colony of this kind, in which the
capsules, each containing perhaps a dozen of them, cover
a large proportion of the shoots, and are crowded in clus-
ters on the creeping fibre, must be enormous ; and it must
be remembered, in estimating the produce, that each of
the zooids bears the seed of many colonies. Specimens
are often coloured red, the colour being due to a very
minute alga, which covers the surface with a network of
chain-like vegetation. O. geniculata is a phosphorescent
species ; and the sudden illumination of a forest of it on
some sombre Laniinariaii frond is a truly beautiful spec-
tacle. If it is agitated in the dark, a bluish light runs
along each stem, flashing fitfully from point to point as
each polypite lights up its little lamp.

Hab. On seaweed, and especially the fronds of Lami-
naria digit ata, near low-water mark; very common and
generally distributed.

[Massachusetts, U. S. (Agassiz) : Hamilton Inlet, La-
brador, in 15 fath. (T. H.): North Cape and neighbouring
coasts (Sars).]

2. O. GELATINOSA, Pallas.

SEIITULARIA GELATINOSA, Pallas, Elench. 116; Fleming, Edinb. Phil. Journ.

ii. 84.
LAOMEDEA GELATIXOSA, Lamx. Corall. flex. 92 ; var. (3, Johnst. B. Z. 104,

pi. xxvii. fig. 1 ; Hincks, Devon. Cat., Ann. N. H. (3rd eer.)

viii. 259.
CAMPA.VULARIA GELATINOSA, Lamk. An. e. V. (2nd ed.) 134.

Plate XXYI. fig. 1.

SHOOTS clustered, rising from a fibrous and spongy
mass ; STEM compound, made up of numerous delicate
tubes, closely bound together, tapering upwards, straight

152 CAMPANULARIID^E.

or very slightly sinuous, of a dark brown colourj thickly
branched; branches given off at short intervals in pairs,
which are placed alternately on opposite aspects of the
stem, so as to present a subverticillate arrangement, com-
pound for some distance above the point of origin,
the upper portion consisting of a single tube and very
hyaline, divided and subdivided into very numerous
alternate ramules, and annulated above the divisions ;
HYDiioTHEC^E very small, of the thinnest texture, cam-
panulate, supported on rather long ringed and tapering
pedicels, the margin cut into denticles of a castellated
form, slightly hollowed out at the top; GONOTHEC^E
axillary, ovate, somewhat flattened at the top, with a
raised aperture.
GONOZOOID with 16 arms at the time of liberation.

PALLAS'S description of this species is admirable, and it is
the only one we possess that is not positively incorrect.
Fleming took the rim of the calycles to be
plain, and conjectures that Pallas may have Fig. 17.
seen the tips of the tentacles showing above
the edge and mistaken them for crcnations !
Johnston adopted Fleming's opinion on this
point, and has besides confounded the true
O. gelatinosa with a very different form, the
Campanularia flexuosa (Hincks) . Many sub-
sequent authors have accepted his view ; and much con-
fusion lias been the result. Milne-Edwards, supposing
Fleming's even-rimmed Campanularia to be distinct from
Pallas's Sertularia gelatinosa, has made it a species and
given it the name of Laomedea Flemingii; but there is
no doubt that Fleming had the same form before him
as the Russian naturalist*, the crenature having escaped
his notice owing to the extreme tenuity of the margin.

•;' I have been informed by the late Mr. Alder that he had examined speci-

OBELIA GELATINOSA. 153

0. gelatinosa is a well-marked species ; it attains a
height of 8 or 10 inches. A fine specimen procured at
Ex mouth was about 6 inches high, and consisted of an
exquisite cluster of as many as 10 shoots.

The branches, which are divided into a multitude of
extremely delicate ramules, are of a tender, pellucid white-
ness, with the exception of the basal portion, and contrast
with the thick and dark-coloured composite stem ; they
occur in pairs, which originate close together on the stem,
but immediately diverge ("furcts in modum ") and spread
out on each side. They are long in the lower portion and
middle of the stem, drooping slightly, and diminish in size
above, giving a very elegant form to the shoots.

A single calycle commonly springs from the fork formed
by the dichotomous division of the branchlets. The pedi-
cels of the terminal calycles are of unusual length, ringed
at the top and bottom and smooth between.

Hob. Between tide-marks ; not common. Exmouth
(T. H.) : Cornwall (C. W. P.) : " very abundant on some
points of the Solway at low- water mark on a stony bottom JJ
(Sir W. Jardine) : the Tay, towards Flisk beach, in brack-
ish water (Fleming) : Shetland (Dr. Cohlstream) : Liverpool

mens of 0. gelatinosa received from Fleming, and had assured himself that
they were really identical with Pallas's zoophyte. Kirchenpauer, in his
interesting work entitled ' Die Seetonnen der Elbmimdung ' suggests that
Fleming may have had before him the form which I have named L.flcxuosa,
and that Milne-Edwards should have the credit of first perceiving its
claim to specific rank. In this case his name (Flemingii) would supersede
flcxuosa. But Fleming's description could not apply to the latter form ; so
that, even if we had not Alder's unimpeachable testimony, the supposition
would be untenable.

The Campanularia gelatinosa of Van Beneden's Memoire has no right
to its name. It is quite distinct from the present species, and is probably the
S. longissima of Pallas. Amongst American authors, Leidy, Stimpson, and
Gould have applied the name to species which differ, I believe, from the
one to which it properly belongs.

154 CAMPANULARIID^.

(Dr. Collingwood). Dr. Collingwood writes, "The most
common and characteristic zoophyte (next to Tubularia
indivisa, perhaps) of our shores. It is interesting as
being a favourite feeding-ground for some minute forms of
Nudibranchiata (e. g. Eolis despecta, E. exigua, E. con-
cinna)." It is in the greatest profusion in the tide-pools
of the Dingle Rocks, where it attains a large size. Also
abundant at Egremont, Hilbre Island, and other places.
[" Mare Belgium alluens," Pallas.]

3. O. LONGISSIMA, Pallas.

SERTULARIA LONGISSIMA, Pall. Elencb. 119.

MONOPYXIS LONGISSIMA, Ehrenb. Corall. roth. Meer. 73.

LAOMEDEA DICIIOTOMA, Tar. /3, Juhnst. B. Z. 102.

LAOMEUEA LONGISSIMA, Alder, North. & Durh. Cat. in Trans. Tynes. F. C. iii.
121 ; Suppl. Trans. Tynes. F. C. v. 237 ; Hincks, Devon. &
Cornw. Cat,, Ann. N. H. (3rd ser.) viii. 259.

CAMFANULARIA GELATINOSA, Van Beneden, Meui. sur les Campanul. 33,
pi. i. & ii.

Plate XXVII.

STEM filiform, flexuous, giving off much-ramified branches
at short intervals and ringed above their origins, of a
dark horn-colour, sometimes black, and of great length ;
branches alternate, long and spreading, the principal
stem flexuous, with pinna springing from each bend,
which are themselves more or less branched, amiulated
above every division ; HYDROTHEC.E campanulate, rather
large and deep, of very delicate texture, the margin cut
into blunt and shallow teeth, borne on rather long
ringed pedicels, which taper upwards ; GONOTHECJE
axillary, ovate, smooth, with a raised central aperture.

GONOZOOID (at the time of liberation) with 20-24 tentacles.

O. LONGISSIMA attains a height of a foot or upwards, and is
of very graceful habit. Its form is somewhat pyramidal, as

OBELIA LONGISSIMA. 155

the branches gradually decrease in length towards the apex.
The stem is distinctly flexuose and of a very deep horn-
colour, becoming black in older specimens. The branches,
which towards their extremities are very delicate and light-
coloured"^, are placed at no great distance from one
another, and are in most respects copies in miniature of
the parent stock. Their pinnee, which diminish in size
towards the top of the branch, are alternate, and are sub-
divided into numerous branchlets ; the axils of these
braiichlets are commonly occupied by a calycle or a small
shoot. The calycles are frail and deciduous, and it is dif-
ficult to obtain specimens on wrhich they are present.

The C. yelatinosa of Van Beneden is clearly identical
with the present species, although he tells us that the rim
of its hydrothecse is plain. The very shallow dentation of
the hyaline and attenuated margin may easily have escaped
his observation. He has figured the sexual zooid with
well-developed, spherical ovaries. In masses of zoophyte
cast ashore after strong winds this species is often very
abundant, and is at once recognized by its long, dark,
thread-like stems.

Hab. Rather deep water, common : Northumberland,
frequent (J. A.) : Peterhead and Wick, dcepish water ;
Gorran Haven, Cornwall, plentiful (C. W. P.): Eiley, York-
shire; Devon, abundant in the trawl refuse (T. H.): Port-
marnock. Though I am only able to give a few localities
for this species, I have no doubt that it is very generally
distributed. Till lately it had been confounded with O.
dic/totoma f.

[Coasts of Belgium, most abundant (Pallas): Mouth of
the Elbe (Kirchenpauer).]

* " * * snbstantia * * albida, moth'*, fenera," Pallas.

t We owe its restoration to specific rank to the sagacity of Mr. Aider. .-;t.

*T * - i5 ^^»

>x

156 .CAMPANTJLAlirUXE.

4. O. DICHOTOMA, Linnaeus.

" SEA-THREAD CORALLINE," Ellis, Corall. 21, pi. xii. figs. «, A.
SERTULARIA DICHOTOMA, Linn. Syst. 1312 ; Ellis $• Soland. Zooph. 48.
LAOMEDEA DICHOTOMA, var. a, Johnston, B. Z. 102, pi. xxvi. figs. 1, 2; Alder,
North, and Durh. Cat, Trans. Tynes. F. C. iii. 121.

Plate XXVIII. fig. 1.

STEM filiform, slender, nearly straight, irregularly branched,
ringed above the origin of the branches, of a deep horn-
colour ; branches suberect, often very long, and more or
less ramified, ringed at intervals, a single calycle in the
axils ; HYDROTHEC^E alternate, broadly campanulate and
deep, polyhedral above, each side corresponding with a
very slight sinuation of the margin, borne on ringed ped-
icels, which vary in length from 4 or 5 to as many as
16 rings; GONOTHEC.E axillary, slender, smooth, widen-
ing from the base upwards, and terminating above in a
raised, somewhat conical aperture.

GONOZOOID. — UMBRELLA very shallow, without thread-cells;
MANUBRIUM trumpet-shaped ; MARGINAL TENTACLES (at
the time of liberation) 16.

IT is difficult to settle the synonymy of this species, as the
descriptions of the older authors are wanting in minute-
ness and precision, and several kindred forms have been
confounded under the Linnean name dichotoma. I have
retained it for the present form, which^ seems to corre-
spond best with the Ellisian and Linnean species, and have
only given such synonyms as are undoubted.

0. dichotoma is of comparatively humble size, and has
none of the subverticillate mode of growth which gives so
much beauty to its near ally 0. flabellata. The stems and
branches are almost straight ; the latter are irregularly dis-
tributed, often very long and straggling, and more or less
branched. They are intermingled, on the main shoots,
with simple ringed pedicels bearing a single calycle. The

OBELIA FLABELLATA. 157

hydrotheca is large, and both broad and deep. The rim
has usually been described as perfectly plain ; but on close
investigation it is found to be very slightly sinuated, and
the depressions answer to a number of sides or faces, which
give a polyhedral figure to the upper portion of the cup.
This structure can only be detected by careful examination
with the microscope.

The differences between the gonozooids of the different
species of Obelia are very slight, at least in their earliest
stage. The multiplication of the tentacles is carried to a
great extent as the zooid advances towards maturity ;
Gegenbaur describes his Eucope pohjstyla, which he had
traced to a Campanularian stock, as possessing one hun-
dred and twenty of them.

Hab. Common : often parasitical on other zoophytes.

5. O. FLABELLATA, HillclvS.

? SERTULARIA DICHOTOMA, Dalydl, Eem. An. Scotl. 212, pi. xli.
CAMPANULARIA FLABELLATA, Hincks, Ann. N. H. (3rd ser.) xviii. 297.

Plate XXIX.

STEM filiform, somewhat zigzag, branched, strongly annu-
lated above the origins of the branches, of a dark horn-
colour; branches alternate, flexuous, given off at each
bend of the stem, rather short and fan-shaped, divided
and subdivided dichotomously , and ringed above each
division, generally forked immediately above the point of
origin, the arms of the fork tending in opposite directions,
and giving a subverticillate appearance to the ramifica-
tion-, HYDROTHECA alternate, short and subtriangular,
with a wide aperture and an entire margin, borne on
ringed and tapering pedicels of variable length ; GONO-
THEC.E axillary, ovate, somewhat flattened at the top,
with a short tubular orifice, attached by a ringed stalk.

GONOZOOID ?

158 CAMPANULARIIDyE.

THIS species seems to have passed, like 0. lonyissima, as a
variety of 0. dichotoma ; it is of much larger size, rising
to a height of 8 or 10 inches, or perhaps more. The ra-
mification is perfectly regular, the branches short, spring-
ing alternately from the stem, and forking immediately
above the base into two principal shoots, each of which is
divided and subdivided dichotomously. The arms of the
fork tending in opposite directions give the branch its
somewhat flabellate form, and to the whole zoophyte its
verticillate appearance.

The decidedly flexuous character of both stems and
branches offers another point of contrast with 0. dicho-
toma. The calycles, too, are formed on another pattern,
being shorter and subtriangular.

If I am right in identifying this species with the C.
dichotoma of Dalyell (and his description and figure agree
better with it than with 0. longissima, the only other
allied species), the gonozooid has about 23 (probably 24)
tentacles, forming a " pendent marginal fringe." He
gives it the name of Tintinnabulum, from its resemblance to
a hand-bell.

O. flabellata is separated from the preceding species by
a group of distinctive characters — the subverticillate habit,
the flabelliform branches, the flexuous stems, the short
subtriangular calycle, and the much larger size.

Hab. Tenby, on rocks in tide-pools (J. A.) : Scotland
(Sir J. Dalyell).

OBELIA PLICATA. 159

Referred provisionally to this genus.

6. O. PLICATA.
Plate XXX. fig. 1.

SHOOTS clustered; MAIN STEMS composed of a large number
of very slender, flexuous tubules bound together, thick
below and tapering upwards, sending off a multitude of
branches ; BRANCHES, some compound, and some simple
and very delicate, of great length and much ramified,
annulated above the origin of the branchlets ; HYDRO-
THEC/E alternate, broadly campanulate, even-rimmed, and
borne on ringed pedicels.

GONOTHEC^E unknown.

Height between 3 and 4 inches.

THE only other British Obelia which has a thick compound
stem, the O.gelatinosa, differs widely from O.plicata in its
habit of growth and in the character of its hydrothecae.
The latter species forms large clusters of shoots, which
are remarkable for their luxuriant ramification. The main
stem is a bundle of delicate tubes closely adherent to one
another, and gives off branches at short intervals; those
on the lower portion are thick and compound, those above
becoming gradually more slender, until towards the ex-
tremity of the shoot they are perfectly simple. The stem
itself, of course, diminishes proportionately as bundle
after bundle of the tubular strands that compose it is given
off, and tapers away towards the top. The branches are
very long, and clothe the stems densely to the summit ;
they are generally much ramified, so that the habit of the
species is eminently shrubby and luxuriant.

The calycle very much resembles in form that of O.
dichotoma.

Hab. Shetland (J.G.Jeffreys).

160 CAMPANULARIIDJE.

Genus CAMPANUL ARIA, Lamarck (in part) .

Der. Campanula, a bell.

LAOMEDEA, Lamouroux (in part).

? SILICULARIA, Meyen, Nov. Acta &c. xvi. 183-1*.

ORTHOPYXIS, Agassiz (for some of the species), N. H. U. S. iv. 355.

LAOMEDEA, Agassiz, N. H. U. S. iv. 352 ; Allman, Ann. N. II. for May 1864.

GENERIC CHARACTER. — Stems simple or branched, rooted
by a filiform stolon ; hydrotheca bell-shaped and hyaline,
without operculum ; polypites ivith a large, cup-shaped pro-
boscis ; gonotliecce borne on the stems or on the creeping
stolon ; yonophores containing fixed sporosacs, which mature
their products within the capsule.

THE genus Campanularia as now restricted includes no
form that would not come under the Lamarckian definition
of it ; it embraces, however, certain portions of Lamouroux's
Laomedea. Agassiz has formed the genus Orthopyxis for
one or two species in which the sporosac is furnished with
branching gastrovascular canals; the modification, how-
ever, is too trivial to stand as the sole criterion of a genus.
There is no important difference between the sporosac with
these canals and the sporosac without them, so long as they
are not subservient to the purposes of free existence.

Section a. "With simple and unbranched stems.
1. C. VOLUBILIS, Linnaeus.

SERTULAKIA VOLUBILIS, Linn. Syst. (12th ed.) 1311.

" SMALL CLIMBING CORALLINE WITH BELL-SHAPED CUPS," El 'Us, Corall.24,pl. xiv.

fig. a, A.
CAMPANULARIA VOLUBILIS, Alder, North, and Durli. Cat. in Trans. Tynes.

R C. iii. 125, pi. iv. fig. 7.

Plate XXIV. fig. 2.

STEMS rising at intervals from the stolon, which is some-

* This genus is founded on two Campanularian species of simple habit,
bearing a general resemblance to Clytia John&toni or Campanularia volubilis.

CAMPANULARIA VOLUBILIS. 101

times plain, sometimes spirally twisted, and which often
sends off free shoots, rather long, spirally twisted, with
a single spherical ring below each catycle*; HYDROTHECTE
rather narrow and deep, of equal width throughout, till
within a very short distance of the base, when they sud-
denly contract, with about ten shallow, blunt denticles
round the margin ; GONOTHEC.E ON short stalks (2 whorls),
flask-shaped, smooth, with a long narrow neck.

Mr. ALDER was the first to point out that the Sertularia
volubilis of Linnaeus is a distinct species from the Cam-
panularia volubilis of Johnston f. In his ' Northumber-
land Catalogue ' he has defined the characteristics of the
two forms with his accustomed accuracy both of pen and
pencil, and restored to its proper rank one of the prettiest
of its tribe.

The C. volubilis is a small species, and may be readily
known by its spirally twisted (not ringed) stems and the
solitary spherule beneath the calycles. The latter, too,
are much more cylindrical than those of the allied species,
and the denticulation is comparatively minute. The
creeping stem has a fashion of detaching itself and casting
forth long, delicate, and transparent spiral shoots ; when
attached it is sometimes smooth.

The neck of the prettily shaped capsules varies con-
siderably in length. They are generally produced but
sparingly, and scattered singly along the creeping stem;
but I have seen them crowded together in numbers, and
forming a dense mass about the base of the calycles.

Hub. On zoophytes from deep water; widely distributed.

[Norway (Sars) : off Reikiavik, Iceland, in 100 fathoms,

* " At the bottom of each [cup], where they join the stalk, the microscope
discovers to us a very minute spherule or little ball, as in some drinking
glasses." — Ellis.

f The (.'I i/ tiu JuJiiiK/uiii of the present work

M

162 CAMPANULARIID^.

amongst icebergs, on Sertularia (T. H.) : Mingaii Islands;
Henley Harbour (20-30 fath.), Gulf of St. Lawrence (A.
S. Packard, jun.) : Massachusetts (Agassiz).]

2. C. HINCKSII, Alder.

CAMPANULARIA VOLUBILIS, var., Hincks, Ann. N. H. (2nd scr.) xi. 180.

„ HINCKSII, Alder, North. & Durh. Cat. in Trans. Tynes. F. C-

iii. 127, pi. iv. fig. 9.

Plate XXIV. fig. 3.

STEM generally long, with two or three rings at the top
(one of which is included in the cup) and one or two
slight tivists at the base, the intermediate portion smooth j
HYDROTHEC^E deep and very large, with parallel sides,
lined at regular intervals longitudinally, the margin cas-
tellated, or cut into square-topped denticles, which are
slightly hollowed out above; GONOTHEC.E of a much elon-
gated ovate form, becoming narrower towards the upper
extremity, which is truncate, divided by transverse rings
into numerous (10-12) rounded and not very prominent
segments, and attached by a short, smooth stalk.

C. HINCKSII is remarkable for its large, lineated calycles,
with a castellated rim which is ornamented with as many
as fourteen square-topped denticles. The pedicels vary in
size, but are commonly of considerable length.

The reproductive capsules are beautiful objects, very
long and slender, almost cylindrical in form, and usually
ringed throughout (Woodcut, fig. 18). The spaces between
the rings are very slightly convex and are not carinated.
In some cases, however, the annulation is almost obliter-
ated, and the capsule is in great measure smooth.

The ova are numerous, and piled up like balls, forming
an elongated central mass.

CAMPANULARIA INTEGRA.

1G3

Hab. On zoophytes &c., from moderate depths (10-20
fathoms) to deep water ; rather rare.

Fig. 18.

Torbay, in about 8 fathoms ; Oban, in about 15 fathoms
(T. H.) : Northumberland and Durham, on shells and
zoophytes from deep water, rather rare (J. A.) : Hebrides
(A. M. N.) : Wick (C. W.P.) : Shetland (J. G. J.): north
of Ireland, in deep water, common (Prof. W. Thomson).

3. C. INTEGRA, Macgillivray.

CAMPANULARIA INTEGRA, Macgillivray, Ann. N. H. ix. 465 ; Johnston, B. Z.
109, pi. xxviii. fig. 2.

Plate XXXI. fig. 1.

STEMS long, slender, twisted, with two or three spherical
rings immediately below the caiycle; CREEPING STOLON
smooth ; HYDROTHEC^E campanulate, wide above, tapering
very gradually towards the base, with a plain rim ; GONO-
much elongated, spirally twisted, the volutions

M 2

164 CAMPANULARIID^E.

sharply carinated, truncate above, with a plain circular
orifice, below somewhat abruptly attenuated, and attached
by a short, smooth stalk.

I HESITATE to identify the C. l<evis of Couch with this
species, although it may possibly be nothing else. He
speaks of " the footstalk " as unringed, and dilating gra-
dually into the calycle. The latter part of this description
has no application to C. Integra, nor to any other Cam-
panularia that I know of, while the pedicel of the present
species has always two or three very marked rings at its
upper extremity, and is distinctly twisted below them.

When the capsules, which are profusely developed and
of most elegant form, are present, there are few prettier
sights of the kind than a colony of this species.

Hab. Donmouth (Macgillivray) : Hastings (Saunders)
(it seems to be common on the south-eastern coast) : Ilfra-
combe, on red weed; Filey (T. H.) : on roots of Lamina-
rise and Ascidise, low-water mark, Bamborough (J. A.) :
Wick (C. W. P.) : Belfast Bay.

[C. Integra occurs in immense profusion on weed from
Hamilton Inlet, Labrador, taken up in 15 fathoms. The
capsules are in great abundance and of very large size,
and the whole aspect of the specimens betokens a con-
genial habitat. The calycles have their chitinous walls
greatly thickened.]

4. C. CALICULATA, Hincks.

CAMPANULARIA CALICULATA, Hincks, Anu. JN. H. for March 1863 (2nd ser.),

xi. 178, pi. v. B. ; Attman, Proc. Koy. Soc. Edinb. 1857-58.
C. BREVISCYPHIA, Sars, Middclhavet's Litt. Faun. 49, pi. i. figs. 12, 13.
CLYTIA POTERIUM, Ayassiz, N. H. U. S. iv. 297, pi. xxviii.

Plato XXXI. fig. 2.
STEM a simple pedicel of variable length, with a single

CAMPANULARIA CALICTJLATA. 165

well-marked ring immediately Mow the cahjcle, and
merely crenated or faintly annulated from this point to
the base; HYDROTHEC^E campanulate, with an even rim,
the walls greatly thickened, so as to give the appearance
of a double calycle, and projecting inwards towards the
bottom to form a diaphragm, beneath which there is a
spherical cavity ; GONOTHEC.E shortly stalked, of an ir-
regular oval shape, having a somewhat wavy outline,
truncate at the top, and with a wide aperture.

WHEN I first described this beautiful species, I was fully
persuaded that the calycle was really double, that within
the outer wall there was a distinct inner cup, which im-
mediately enclosed the body of the polypite. I now see
that this was an error, and that the peculiar appearance
which the species presents is due to a remarkable thicken-
ing of the polypary. The terms of my former description
must therefore be modified ; but the name caliculata is still
sufficiently appropriate.

The cavity of the hydrotheca, which is enclosed by a
considerable thickness of transparent chitine, has all the
appearance of an inner cup suspended within the true
calycle. The illusion is complete. In shape it resembles
an inverted hand-bell, the spherical space at the bottom of
it representing the handle.

The form of the hydrothecee is liable to some variation.
Commonly they are not deep, rather wide at the top,
narrowing downwards very slightly, and well rounded-off
below ; but another type occurs, which is more elongate
and tapers off more decidedly, and bears a striking resem-
blance to an old-fashioned wine-glass.

These two forms are generally mingled on the same
specimens. The pedicels are not of such a uniform and
moderate length as I formerly supposed; they have
sometimes as few as 9 or 10, and sometimes as many as
20 crenations or more.

166 CAMPANULARIIL>.£.

The C. breviscyphia of Sars seems to have been founded
on examples of C. caliculata with more elongated stems
and somewhat shorter calycles than those from which the
original description was taken. I have little hesitation
in identifying it with the present species. Sars has ob-
tained specimens of C. caliculata near Bergen on which
the pedicels had more than 30 rings — or, rather, " slight
waves/7 as Agassiz more accurately styles them. As in
other species, there seems to be much variability in this
portion of the structure.

The newly formed calycle is covered by a convex cap,
shaped like a watch-glass, which the polypite pushes off
when fully developed.

The calycles are very tremulous, owing to the deep con-
striction of the stem to form the spherule on which they
rest, and are soon detached after the death of the polypite.

The reproductive capsules (female) contain two sporo-
sacs, a large one above and a smaller one below — or some-
times only one, which occupies, when its contents are
matured, the greater portion of the cavity. Four branched
gastrovascular canals spring from the base of it, amongst
the ramifications of which the ova are placed (Plate XXXI.
fig. 2 d\ The capsule was first described by Sars (' Medi-
terranean Littoral Fauna/ p. 50) ; and its structure and the
development of its contents have been thoroughly investi-
gated by Allman and Agassiz*. The latter has frequently
seen a portion of the contained mass of planules forced
out of the capsule, still enclosed in the sac, and remaining
attached externally.

The planule is ovate, and clothed with vibratile cilia.

* In Agassiz'.s great work on the Natural History of the United States,
this species is described and figured as Clyfia poteriinn. It is to be regretted
that this distinguished author did not pay more attention to the European
forms before naming his American Hydroids, many of which, I believe, are
identical with British species.

CAMPANULARIA VERTICILLATA. 1G7

I am indebted for my first knowledge of this species to
Mr. R. S. Boswell, who many years ago showed me speci-
mens of it exquisitely mounted, according to a method of
his own, so as to display the polypites.

Hub. On the red algoe chiefly (Delesseria sanguined &c.),
near low-water mark and in moderate depths ; not
common.

Pegwell Bay, near Ramsgate (R. S. Boswell) : Old Head
of Kinsalc, co. Cork (R. Allniau) : Ilfracombe; Swauage,
Dorset (T.H.): Courtniasherry Harbour, co. Cork (Gr. J. A.):
Jersey (A.M. N.).

[Messina (var. breviscyphia, Sars); Bergen (Sars): Ha-
milton Inlet, Labrador, 15 fathoms, on red weed (T. H.) :
Massachusetts, " almost invariably attached to seaweeds,
or to the stem of other hydroids " (Agassiz) : Nova Scotia
(teste A. Agassiz.)]

Section b. Branched and with compound stem.

5. C. VERTICILLATA, Linnaeus.

" HOUSE-TAIL CORALLINE WITH BELL-SHAPED CUPS," Ellis, Coiiill. '23, pi. xiii.

figs, a, A.

SEKTULARIA VERTICILLATA, Linn. Syst. 131U; Palais Elench. 115.
CLYTIA VERTICILLATA, Lamx. Cor. flex. 202.
HALECIUM VEKTICILLATUM, Okcit, Lchrb. Nat. 92.
CAMPAXULARIA VERTICILLATA, Lanik. An. s. V. (2nd ed.) ii. 131 ; Juhnst. B. Z.

112, pi. xxvi. figs. 3, 4.
CAPSULAKIA VEUTICILLATA, Gray, B. M. Radiata, 87.

Plate XXXII. fig. 1.

STEMS erect, composed of many parallel tubes, irregularly
branched, obtuse at the top ; branches compound, cylin-
drical; HYDROTHEC.E bell-shaped, rather large and deep,
expanding slightly and very gradually upwards, with
about 12 pointed denticulations on the margin, borne

] 68 CAMPANULAllIIU.E.

on pedicles, which are more or less annulated at the top
and bottom,, patent, and arranged in whorls at regular
intervals ; GONOTHECVE flask-shaped, smooth, with a
narrow neck, and very shortly stalked.

THE term " equisetiform" which Ellis has applied to this
species, gives an admirable idea of the mode in which the
pedicels are disposed on the stem and branches. They
form equidistant whorls, and " give the whole very much
the appearance of the plant called Horsetail or Equisetum."
There are about 5 to each whorl. The calycles are of a
thin and delicate texture. C. verticillata sometimes attains
a luxuriant growth, and is much and variously branched.

Hub. In the coralline zone, on shells &c.; common. It
is taken up in immense quantities by the trawlers on the
south-west coast.

[Tromso, rare; North Cape, common in 30-50 fath.
(Sars) : Henley Harbour, Labrador, in 20 fath. on a pebbly
bottom (A. S. Packard, jun.) : coast of La Charente-infe-
rieure, Bay of Biscay (Beltremieux).]

Section c. With branching stems [Laomedea, Lanix.J

6. C. FLEXUOSA, Hincks.

LAOMEDEA GELATINOSA, var. a, Johnston, B. Z. 105, pi. xxv. figs. 3, 4 ; Couch,

Corn. Faun. 39, pi. x. fig. 2.
LAOMEDEA FLEXUOSA, Hincks, Devon and Cornw. Cat., Ann. N. H. (3rd ser.)

viii.260; Attman, Ann. N. H. for May 1864.

Plate XXXIII.

STEM filiform, flexuous, simply pinnate or irregularly
branched, of a light horn-colour, ringed at the base and
above the origins of the branches; HYDROTHEC^E alternate,
large,<:up-shaped,ivide above, the sides sloping off somewhat
abruptly towards the base, with a plain rim, and borne on
rather long, ringed pedicels (0-7 rings or more), which are
given oft' at each bend of the stem ; GONOTHECA: (female)

CAMPANTJLARIA FLEXUOSA. 169

axillary, very large, elongate, oval, smooth, rather wide
and truncate at the top, attached by a short, ringed
stalk (3-4 rings), and containing numerous sporosacs;
male smaller; POLYPITES with the tentacles slightly
webbed.

C. FLEXUOSA, which was included under Obelia gelatinosa
by Johnston, is one of the commonest of our littoral
zoophytes. In amazing profusion it spreads over a con-
siderable portion of the littoral zone, now half buried in
the mud beneath the loose stones, now covering with its
delicate forests the sides of the tidal pools filled with the
most pellucid of water. It forms also a dense undergrowth
on the surface of the larger rocks, beneath the pendent
weed, where it is left flattened down and half dried on the
recession of the sea. A beautiful sight it is to see the
prostrate forests revive, and waving to and fro with the flux
and reflux of the incoming tide. We cease to be sur-
prised at its abundance when we examine the reproductive
capsules (female)*, which are of enormous size, as compared
with the calycles, and often crowded on the shoots, each
one containing a large number of planules. They are also
occasionally met with on the creeping stolon .

The tentacles of the polypite are united towards the
base by a membrane of extreme tenuity, similar to that
which exists in Campanulina acuminata. The species is
subject to but slight variation. In some situations the
shoots have a tendency to run out above into tendril-like
fibres. The pedicels which support the hydrothecae also
vary considerably in length, and the ramification is more
or less luxuriant; but the flexuous habit, the broad,
obconic, and even-rimmed calycle, and the gigantic capsule
are constant and striking features.

* The male capsule is much smaller than the female (vide Plate XXXII I.
fig. f>), and somewhat different in shape.

170 CAMPANULARIID^.

C. flexuosa attains a height of about an inch.
Hab. Confined to the littoral region, and extremely
common on all parts of our coast.

Shetland, Jersey, Cornwall, Isle of Man, Ireland, &c.

7. C. ANGULATA, Hincks.

"Catalogue of Devon and Cornw. Zooph.," Ann. N. H. (3rd ser.) viii. 26],
pi. viii.

Plate XXXIV. tig. 1, and Woodcut, fig. 14.

STEM slender, simply pinnate or very slightly branched, zig-
zag, the spaces between the bends very long, ringed at the
base and above the origin of the pedicels, often produced
at the extremity into long, tendril-like claspers ; HYDKO-
THEC,E alternate, canipanulate, rather deep, tapering
gradually downwards, even-rimmed, borne on very long
ringed pedicels, which are given .off at each flexure, and
are slightly attenuated above; GOISOTHECJE irregularly
ovate, with a feio obscure wrinkles, and occasionally one
or two projecting points, terminating above in a short,
broad neck, ivhich is somewhat truncate at the top, deve-
loped on the creeping stem and attached by a short, ringed
stalk (3-4 rings) ; POLYPITE with about 24 remarkably
long and slender tentacles.

Height from | to f inch.

THIS species may be known by the great length of the
internodes, which bend from side to side and form a series
of obtuse angles, and of the tapering pedicels that support
the calycles. They have commonly from 9-12 rings, and
sometimes nearly 20 ; occasionally there is a smooth por-
tion about the middle of the pedicel. The tendril-like
prolongation of the stem is also a striking feature ; it is
often of great length, much thickened above, and strongly
annulated towards the lower end. Specimens occur in

CAMPANTJLAftlA NEGLECTA. 171

which the stem is only about -J of an inch in height,
with two or three calyclcs, while the tendril is fully \ an
inch long.

The capsules, so far as I have seen, are never borne on
the stem ; they are somewhat variable in shape. All the
specimens that I have hitherto examined are on the Zoster a.
The creeping stem runs along the leaf, giving off erect
shoots at short intervals, and between them the capsules
are ranged ; they commonly spring from the side of the
stolon and are therefore recumbent on the surface of the
leaf.

Hub. On Zostcra marina. Ramsay, Isle of Man ; Tor-
bay (T. H.) : Jersey (abundant on Zoster a) (A. M. N.) :
Youghal (Miss Ball) : North of Ireland (Prof. W.
Thomson) .

8. C. NEGLECTA, Alder.

LAOMEDEA NEGLECTA, Alder, Northumb. & Durli. C'at. iu Trans. Tynes. F. C.
iii. 123, pi. v. figs. 1, 2 ; Hincks, Devon & Cormv. Cat., Ann.
N. II. (3rd. ser.) viii.

Plate XXX. fig. 2.

ZOOPHYTE delicate and of very humble growth; STEM fili-
form, subfleosuose, simply pinnate, annulated (4-7 rings)
above the origin of each pedicel, and sometimes slightly
ringed below ; HYDROTHEC^E alternate, narrow and deep,
borne on ringed pedicels, with about 8 bimucronated
denticles round the margin ; GONOTHEC^E pyriform, axil-
lary or borne on the pedicels, with a short, ringed stalk,
— ova matured in an external marsupium ; POLYPITE
with 15-16 slender tentacles.

IN its usual condition this is a very minute species, at-
taining a height of about j~j of an inch, very sparingly
branched or perfectly simple, each stem bearing a single

172 CAMPANULARIID.E.

calycle. In Devonshire, however, I have found it of much
larger size (about | of an inch high), more decidedly
branched, and bearing the reproductive capsules in abun-
dance. They are produced in the axils; and sometimes
one is present a little above them on the pedicel that
supports the hydrotheca. They contain one sporosac,
which buds from the side of the upper part of the axial
column, and ultimately becomes terminal. It bears two
or three ova, and is at last carried up and pushed through
the orifice of the capsule, becoming invested with a thick
gelatinous covering, and forming a nest in which the eggs
are hatched into planuloid embryos.

The margin of the calycle in C. neglecta is of extreme
tenuity, and it is a matter of no slight difficulty to define
the subturreted crenulations.

Hub. On the underside of stones, between tide-marks,
and on other zoophytes &c., from inshore to the coralline
region; common.

9. C. EXIGUA, Sars.

CAMPANUI/ARIA, Gegenbaur, Generationswechscl bei Medus. u. Pol. 35 (note),

pi. i. figs. 5, 6.
LAOMEDEA EXIGUA, Sars, Midclellmvet's Litt. Faun. 50.

Plate XXVIII. fig. 2.

STEM very delicate, slightly flexuous, giving off at each
bend simple pedicels, ringed at the base and upper
extremity (the intermediate space being smooth), which
support the calycles; HYDROTHECA very small, regu-
larly funnel-shaped, xoith an even rim ; GONOTHEC.E axil-
lary, elongate, smooth, somewhat fusiform.

Height about \ inch.

Tins very minute species was first described and figured by

CAMPANULARIA DECIPIENS. 173

Gegenbaur, who also investigated its reproductive history,
but did not name it. The calycles are almost trian-
gular, with perfectly straight sides (" ohiie Ausbuchtung").
The pedicels are described by Gegenbaur as only annulated
at the top and bottom, the central portion being plain ; but
this is probably not a constant character. The stem is
ringed at the base and above each branch. The capsules
are elongate, tapering off towards the base, and narrowed
for a short distance below the truncate extremity; they
are filled with numerous sporosacs.

Hub. On zoophytes, Swanage, Dorset (T. H.).

[Messina (Gegenbaur and Sars): Belgium, where it
attains a rather large size (Van Beneden).]

10. C. DECIPIENS, T. Strethill Wright.

" Observat. on Brit. Zooph.," Journ. of Micr. Sci. (N.S.) iii. 49, pi. v. fig. y.

ZOOPHYTE minute ; STEM filiform, flexuous, annulated with
about 5 rings above the origin of the pedicels which
support the hydrothecse; HYDROTHEOE widening rapidly
towards the top, ivith even, double rims, borne on ringed
pedicels ; POLYPITES with about 16 tentacles.

" THIS pretty little Laomedea resembles much the L. ney-
lecta of Alder, except that the margin of the cell is even
and has the appearance of being double for about half
its length from the rim, though, from the extreme delicacy
of the cell, this character is only made out with difficulty."
(Wright.} The reproduction is described as exactly similar
to that oWjjercularella lacerata, except that the marsupium
of C. decipiens contains only three ova, while that of 0.
lacerata contains six or eight.

A more minute diagnosis is much to be desired. So

174 CAMPANTJLARinXE.

slight a description, unaccompanied by any figure but one
of a single calycle, is not sufficient for the purpose of
identification.

Hub. Firth of Forth (T. S. W.).

Species referred provisionally to this genus.

C. (?) GIGANTEA,

" On new British Hydroida,'' Ann. N. II. for October 1866 (3rd ser.) xviii.
297.

Plate XXXV. fig. 1.

STEMS delicate, of a very light horn-colour and papyraceous
texture, annulated at the base and below the calycle,
irregularly and sparingly branched; branches erect,
copies of the primary shoot, sometimes themselves
branched ; HYDROTHEC^E of enormous si~e, deeply cam-
panulate, very wide at the top and for some way below it,
and then tapering off gradually, length about double the
greatest width, the rim cut into broad and blunt teeth ;
GONOTHEC^E unknown.

Height about an inch.

THIS well-marked form may be at once recognized by the
extraordinary size of its calycles, which arc very much
larger than those of any other known species. They vary
somewhat in breadth, but their dimensions are always
gigantic for the tribe.

The general habit of growth resembles that of Gono-
thyrtea gracilis (Sars). The primary shoot sends off one
or more branches, generally at a considerable height above
the base, each of which is a pretty exact copy of itself.
These branches are somewhat constricted at their origin,
and closely ringed for some distance above it ; they ter-

CAMPANULARIA FRAGILIS. 175

minate in a single calyclc. Occasionally the branching is
carried further ; but in all the specimens which I have seen
it is simple and scanty. Below the calycle there are
several well-marked, somewhat compressed rings. The
stems are singularly tender and transparent.

I am indebted to Prof. Wyville Thomson for the speci-
men from which this description is taken. Unfortunately
he was unable to study the reproduction, so that the species
can only be provisionally placed.

Hob. Lamlash Bay, Arran, 011 shells (Prof. Wyville
Thomson) .

C.? FRAGILIS, Hincks.

LAOMEDEA FRAGILIS, HincJcs, Ann. N. H. for January 18(53, xi. (3rd. ser) 40,

pi. ix. fig. 3.
? CAMPANULARIA ELONGATA, Van Bcnedcn, Fauno Litt. cle Belgique, Polypes,

1G4 & 150, fig. 6.

Plate XXXII. fig. 3.

ZOOPHYTE very minute and delicate ; STEM flexuose, giving
off alternately, at each flexure, ringed and tapering pe-
dicels, which support the culycles, annulated above the
origin of each pedicel; HYDROTHEC.E much elongated and
very narrow, attenuated below, -with an even rim. Re-
production unknown.

Height about \ inch.

THIS species is smaller and more delicate even than the
C. neglecta (Alder), and it is as graceful in form as it is
fairy-like in size. The stem is decidedly flexuous, and
the calycles are remarkable for a combination of (com-
paratively) great length and narrowness. When the poly-
pite is extended, only the proboscis and the wreath of ten-
tacles are beyond the orifice.

I suspect that the C. elongata of Van Bcnedcn is iden-

176 CAMPANULARIID^E.

tical with the present species. He has figured a single
hydrotheca, which corresponds exactly with that of C. fra-
gilis ; and his description,, in all important points, agrees
with the one just given. He has noticed especially the
very minute size*.

Hob. In pools on the lower ledges of the Capstone,
Ilfracombe, forming miniature groves oil the underside of
stones (T. H.).

[(C. elongata] Coast of Belgium (Van Beneden).]

C. ? RARIDENTATA, Alder.

Suppl. North, and Curb. Cat. in Trans. Tynes. F. C. v. 238, pi. x. fig. ."-.

Plate XXVI. fig. 2.

STEM short, simple, rising from a slight bulbous expansion
of the stolon, ringed above and below, and bearing a
single calycle ; HYDROTHEC^: rather long and narrow,
tapering a little towards the base, and with 5 or 6 deep,
pointed crenulations round the margin; GONOTHEC^:
unknown.

Height ^Q inch.

A MINUTE species, with a slender calycle and a very small
number of marginal denticles.

Dr. Strethill Wright has succeeded in rearing a Cam-
pannlarian from the planules of Thaumantias inconspicua
(Forbes) which bears a close resemblance to the present
species f. It is not improbable that C. raridentata may
prove to belong to the same genus.

Hob. On other zoophytes from deep water, Cullercoats,

* " Cette espece est tellement petite qu'avec une bonne loupe ordinaire on
la distingue a peine ; elle nous avait lungtemps ecbappe." — Polypes (1SGG),
p. 164.

t Journ. oi' Microscop. Science for October 1862, pp. 221 & 308.

LOV^NELLA CLAUSA. 177

occasionally (J. A.) : on coralline &c. between tide-marks,
Torquay ; on zoophytes, amongst the Brixham trawl-re-
fuse, not uncommon ; Swanage Bay, Dorset, common in
5-7 fathoms (T. H.).

Genus LOVENELLA, Hincks.

Der. Named after the distinguished Swedish naturalist, Loven.

GENERIC CHARACTER. — Stems simple or slightly branch-
ing, rooted by a thread-like stolon ; hydrotheca turbinate,
elongate, crowned with a distinct, conical operculum, com-
posed of many convergent segments ; polijpites with a large
and prominent proboscis.

Reproduction unknown.

THIS genus is distinguished from its allies by its long
(but not tubular) operculated calycles. Its polypite is of
the same type as that of Campamdaria.

L. CLAUSA, Loven.

CAMPANULARIA CLAUSA, Loven, Bidrag till Kannedomen af Slagtena Campan.
och Syncoryna, 3 (note).

Plate XXXII. fig. 2.

STEMS simple or very sparingly branched, with a few rings
at the top and bottom, the intermediate portion crenated
or wavy ; branches short, simple, erect, supporting a
single calycle; HYDROTHEC^E hyaline, very long and
slender, tapering off gradually below, the rim cut into
shallow crenations, which correspond with the segments
of a turret-shaped operculum, composed of about 8 pieces
that converge and meet in a point ; POLYPITE with about
15 tentacles; GONOTHEC.E unknown.

THIS beautiful species was characterized by Loven inci-
dentally in a note to his famous paper on Campanularia and
Syncoryna. It had not, I believe, attracted the notice of
any subsequent author; and supposing it to be new to

N

178 CAMPANULARIID2E.

science, I described it at the meeting of the British Associ-
ation in 1864 from Devonshire specimens, and gave it the
very name which the Swedish naturalist had already be-
stowed upon it. -. )

The species is at once known by its remark-
ably long, slender, and graceful calycles, with
their turret-like opercula. The habit is compa-
ratively simple, the primary shoots occasionally
bearing a single short branch. The hydrothecse
are much produced and attenuated below, and
the space between the diaphragm on which the
polypite rests and the base is unusually great
(Woodcut, fig. 19).

Hab. On stones, dredged off the Oar Stone,
at the entrance to Torbay, in about 10 fathoms (T. II.).

[On Fuel from stony ground, off the coast of Sweden
(Loven) .]

Genus THAUMANTIAS, Eschscholtz* .

TIIAUMANTIAS, Forbes (in part), Erit. Naked-eyed Medusae, 41 ; Gegenbaur,
Versuch. einer Syst. d. Medus., Zeitsch. fur wissenschaft. Zool.
viii. 237.

GENERIC CHARACTER. — Stem simple (or branched!},
rooted by a thread-like stolon; hydrotheca campanulate;
polypites with a prominent funnel-shaped proboscis ; repro-
duction by free medusiform zooids.

Gonozooid : Umbrella hemispheric; manubrium flipped ;
radiating canals 4; marginal tentacles numerous; spoi'osacs
in the course of the radiating canals ; lithocysts wanting.

THE Thaumantias of Eschscholtz was founded on the
Medusa hemisphterica of Grouovius, a species which is

* Syst. dcr Acaleph. p. 103.

THAUMANTIAS IXCONSPICUA.

179

destitute of lithocysts. Forbes has adopted it, and made
it include a number of forms, generically distinct, of which
some are referable to Obelia and Clytia. Gegenbaur has
properly retained the name for the section that agrees Avith
the type species in not having lithocysts.

Only the reproductive phase was known until Dr. Wright
succeeded in rearing from the egg the polypites of T. in-
conspicua, and thus determining the position of the genus.

I see no reason for withdrawing Thaumantias from the
family of the Campanulariidfe.

T. INCONSPICUA, Forbes.

Monograph of the Erit. Naked-eyed Medusae, 52, pi. viii. fig. 3; T. S.
Wright, Journ. of Micr. Science (N. S.), ii. 221 & 308.

Woodcut, fig. 20.

STEM simple, ringed at the base and immediately below the
calycle, or sometimes through-
out; HYDROTHEC.E with from Fig. 20.
seven to nine deuticulatioiis on
the margin ; GONOTHEC.E un-
known.

GONOZOOID. — UMBRELLA smooth
and colourless, measuring
about |- inch across ; MANU-
BRIUM narrow, quadrangular,
and of a yellow colour, with
lanceolate lips; MARGINAL TEN-
TACLES increasing in number with age (16-40), springing
from small pale-yellow bulbs, with a faint tawny spot ;
SPOROSACS long and linear, and of a faint lilac or greenish
hue, with a central fulvous line.

DR. WRIGHT describes the trophosome as closely resembling
that of Campanularia raridentata (Alder) . The annulation

x 1

180 CAMPANTJLARIID.E.

of the stem varied amongst the specimens which he suc-
ceeded in rearing ; in some cases it extended throughout,
in others it was confined to the top and bottom. In some
of the young zoophytes the ringing at the base ' ' was pre-
ceded by a slight dilatation ; " the denticulations on the
margin of the calycle were usually seven in number. The
mature trophosome has yet to be observed.

Forbes gives the number of tentacles on the free zooid

.at from 16 to 20; but he adds that between each pair

there is a rudimentary marginal tubercle, which would no

doubt be developed into a perfect tentacle. There may,

perhaps, be a still further increase in number.

Hub. Hebrides, common (Forbes) : Firth of Forth
(T. S. W.).

Genus GONOTHYILEA, Allman.

Der. y6vos, offspring, and Svpalos, outside the door.
LAOMEDEA, Lamouroux (in part).

GENERIC CHARACTER. — Stem erect and branched, rooted
by a thread-like stolon ; hydrothecte campanulate and hya-
line ; pohjpiteft ivith a prominent contractile proboscis ; re-
production by fixed medusiform sporosacs, which are fur-
nished with a circle of filiform tentacles, and, when mature,
become extracapsular, and are borne on the summit of the
gonotheca.

THERE is nothing to distinguish this genus from Cam.
panularia or Obelia but the structure and history of the
sexual zooids, which exhibit some very interesting pecu-
liarities. They are medusiform, but never become free :
the generative products are developed as in an ordinary
sporosac; but before their liberation the gonophore is

GONOTKYR^EA LOVENI. 181

carried upwards by the growth of the axial column, and
at length is pushed beyond the orifice of the capsule, and
remains attached externally until the contents are matured
and discharged, when it withers away. The gonozooid in
this genus combines to some extent the characters of the
free and fixed forms; it links the one to the other, and
shows the impossibility of separating them structurally by
any hard line of demarcation.

1. G. LOVENI, Allman.

" SEA-THREAD CORALLINE," Ellis, Corall. pi. xii. C, and xxxviii. B.

CAMPANULARIA DICHOTOMA, Lister, Phil. Trans. 1834; Van Beneden, Faune

Litt. de Belg. Polypes, 156, pi. xv. figs. 1-4.

,, GENICULATA, Lovhi, Wiegmann's Arcbiv, 1837; Schultzc,

Muller's Archiv, 1851 ; Van Beneden, Mem. sur les Cam-
pan. 34, pi. iii. figs. 1 & 6V

LAOMEDEA DICHOTOMA, T. Strethitt Wright, Edinb. New Phil. Journ. (N. S.)

for Jan. 1859.
., LOVENI, Allman, Ann. N. H. for August 1859.

GONOTHYK.EA LOVENI, Allman, Ann. N. H. for May 1864.

Plate XXV. fig. 2.

STEM erect, flexuous, irregularly branched, annulated above
the origin of the branches and polypiferous rarnuli; HY-
DROTHECjE alternate, deeply campanulate, narrow, the
margin with 10 small and blunt denticles, borne on short
ramuli, which are ringed throughout; GONOTHEC^E broad
and truncate at the top, tapering off to the base (obconic],
supported on short annulated stalks, axillary, carrying
on the summit, when mature, from 2 to 5 of the extra-
capsular sporosacs.

THE history of this species is interesting. Its peculiar
mode of reproduction was noticed by Ellis, who has' given
an excellent figure of it, but identifies it with his Sea-
thread Coralline. Lister, in his well-known paper in the
'Philosophical Transactions' (1834), described the male

182 CAMPANULARIID^E.

organs, but left the question of specific distinctness un-
touched. In 1836, Loven. published an account of the
female, accompanied by admirable figures, which is of the
highest value ; but he wrongly referred it to the Campanu-
laria geniculata. Schultze, in turn, investigated its his-
tory, adopting LoveVs name for it. At a later period,
Dr. Strethill Wright recognized its claims to specific rank,
and gave a detailed account of its reproduction, but re-
tained for it the name of Laomedea dichotoma, which be-
longs to another well-marked form. Alder suggested its
separation from Laomedea flexuosa, with which Allman
had at first identified it ; and the latter subsequently raised
it to specific and then to generic rank, and completed the
interpretation of its history. Few species have been pri-
vileged to receive the special attention of so many distin-
guished naturalists.

G. Lovetii ordinarily grows in tree-like tufts, much and
irregularly branched, and attains a height of about half
an inch. Prof. Allman, however, mentions a large variety
which is three or four inches high, and forms " long, lax
tufts."

In the absence of the capsule, the best distinctive mark
is to be found in the shape of the calycle, which is rather
deep and slender, contrasting strongly in this respect with
that of Campanularia flexuosa, perhaps its nearest ally, and
has in addition a denticulated rim. The teeth are small
and blunt, and very readily escape observation.

The tentacles on the female sporosacs are well-developed
and vary in number; on the male they are smaller and
less numerous.

Hab. On the fronds of the larger seaweeds at low-
water mark, and occasionally on stones, in tide-pools.
Brighton (Lister) : Dartmouth and Torquay, on Fucus ;
near Dunolly Castle, Oban, in profusion on weed and

GONOTHYll^EA GRACILIS. 183

stones (T. H.) : on stones between tide-marks, at Culler-
coats (J. A.) : Cramoncl Island, Firth of Forth, on Fucus
vesiculosus (G. J. A.) : Shetland (A. M. N.): Carrickfergus,
on weed and wood close to low-water mark ; Moukstown,
near Cork, on the pier (Wy ville Thomson) .

[Coast of Belgium (Van Beneden) : Sweden (Loven).]

2. G. GRACILIS, Sars.

LAOMEDEA GRACILIS, Sars, Beretning om en Zoolog.-Eeise i Lofoteii og Fiu-
marken, 18; Middelhavet's Littoral-Faun. 51, pi. ii. figs. 1-4.
GONOTIIYK.EA GRACius, Allman, Ann. N. H. for May 18(34.

Plate XXXVI. fig. 1.

STEM very slender, straight, giving off branches sparingly
and at irregular intervals, ringed at the top and bottom
and above the origin of the branches, which resemble
the primary stock, and are frequently in their turn
branched; HYDROTHEC.E much elongated, campanulate,
slender, the margin with about 12 long, pointed denticles ;
GONOTHEC/E subcylindricttl, smooth, the upper extremity
truncate, tapering off below, attached by a ringed peduncle
(5 or 6 rings) , and borne on the stems and creeping stolon.

THE branching of this species is peculiar. In the speci-
mens that I have examined, the primary stem bears a
single shoot, which has the appearance of growing upon it
rather than out of it, and this in its turn bears another
precisely similar to itself. The branching is carried much
further in well-grown examples, as may be seen in Sars's
figure. Sometimes the branches are separated by consider-
able intervals; sometimes two spring from opposite points
on the stem.

There are two rings immediately below the calycle, and
at the base of both main stem and branches ; and above
the origin of the latter there is an animlatcd space.

184 CAMPANULARIID^E.

The calycles are of a most elegant form, deep and nar-
row, tapering off gradually towards the base, but having
the sides parallel for the upper two-thirds of their length.

The capsules are borne on the creeping fibre as well as
on the stem, and not exclusively on the latter as stated
by Sars ; they are longer than the calycles, but slenderer,
somewhat narrowed towards the truncate top, of a pro-
duced oval shape below, tapering off towards the base.

Sars has described the female gonozooids. The sporo-
sacs, when attached to the top of the capsule, are furnished
with a circle of short tentacles, and contain two ova.

Hab. On the tests of Ascidians, sponge, and zoophyte ;
dredged in Birterbuy Bay, Conuemara (G. S. Brady).

[Bergen, attached to Laminaria saccharina, not rare
(Sars). The same naturalist describes a form found at
Messina, which he regards as a variety of the above. It
differs from it in having somewhat shorter and broader
calycles, with smaller denticles on the margin.]

Referred provisionally to this genus.

G. ? HYALINA, Hincks.

'• On now British Hydroida," Ann. N. H. xviii. (3rd ser.) 297.

Plate XXXV. fig. 2.

SHOOTS densely clustered on the creeping stolon, tall and
much branched; MAIN STEMS very slightly flexuous, of a
deep horn-colour below, becoming white and very delicate
towards the upper extremity, giving off branches at each
bend, strongly annulated at the base and above each
division ; branches erect, flexuous, very tender and hya-
line, sometimes of great length and much ramified — a single
calycle or a branch springing from each axil; HYDRO-
THEC.E alternate, much elongated, slender, of very thin

GONOTHYR^EA HYALINA. 185

texture, with nearly parallel sides for two-thirds of their
length, and then tapering off to the base, borne on ringed
pedicels, the rim cut into numerous shallow denticles of
castellated form, slightly indented at the top ; GONO-
THEC.E axillary, irregularly ovate, flattened at the top,
and supported on a ringed stalk.
Height about 2 inches.

I PLACE this fine species provisionally in the genus Gono-
thyraea. The reproduction has not been traced ; but, from
the structure of the capsule, I have little doubt that this
will prove to be its right position. It is difficult to give
a concise, and at the same time accurate, description of the
form of the gonotheca; it is long, truncate above and
tapering below, straight on one side and curved outwards
on the other.

The ramification is irregular and luxuriant ; branches are
given off at each of the slight flexures of the stem, but they
vary much in length and complexity ; their growth is erect,
so that the shoots are comparatively narrow and slender.

A very striking feature of the species is the remarkably
tender and hyaline character of the branches and of the
extremities of the main shoots, which are of a most
delicate whiteness.

There is very great variation in the length of the pedi-
cels supporting the hydrothecffi, the number of rings
ranging from 4 or 6 to nearly 20. The calycles are large
and very graceful in their proportions.

Hab. Profusely investing Tubularia, Halecium halecinum,
&c. from Shetland, and, I believe, from deep water. I am
indebted for my specimens to Mr. Jeffreys, who has so
energetically and thoroughly explored the Shetland seas
with the dredge, and who has not forgotten his brother
naturalists while attending to his own special department
of the science.

186 CAMPANUHNIDJ-:.

Family II. — Campaimlhiidse.

HYDROTHEC.E ovato-conic, pedicellate ; POLYPITES cylindri-
cal, ivith a small conical proboscis.

IN this family the campanulate calycle disappears, and
the polypite is of the long, slender, cylindrical type, taking
its origin at the very base of the hydrotheca and termi-
nating above in a short, conical proboscis, instead of the
large trumpet-shaped organ which belongs to the true
Campanulariidce.

Genus CAMPANULINA, Van Beneden.

Der. From Campanula, a bell.

GENERIC CHARACTER. — Stem simple or branched, rooted
by a thread-Hike stolon ; hydrothecce produced and pointed
above ; polypites cylindrical, with ivebbed tentacles ; repro-
duction by free medusiform zooids, a single one of which is
contained in each capsule.

Gonozooid: Umbrella (at the time of liberation] deep
bell-shaped; manubrium short and ^-lipped; radiating
canals 4 ; marginal tentacles 2 or 4, with bulbous bases ;
lithocysts 8, borne on the margin of the umbrella, one on
each side of the primary tentacles.

THE medusiform zooid in its earliest stage bears a gene-
ral resemblance to that of Clytia, and subsequently passes
through much the same course of development. The
tentacles and lithocysts increase in number ; and the um-
brella, which is at first deep bell-shaped, becomes more and
more depressed, and finally assumes the shape of a flattened
segment of a sphere. These changes have been observed by
A. Agassiz in the Oceania languida, which is no doubt the
reproductive zooid of a member of the present genus. The
tentacles in this species increase from two to about forty.

CAMPANULINA ACUMINATA. 187

1. C. ACUMINATA, Alder.

CAMPANTJLINA TEXUIS, Van Bencden, Un mot sin- le mode cle Reproduct. dcs
An. infer., Bullet, de 1'Acad. Roy. de Belgique, xiv. no. 5,
fig. 6; Faune Litt. de Belg. Polypes, 174, pi. xiii.

LAOMEDEA ACUJIIXATA, Alder, North. & Durh. Cat. in Trans. Tynes. F. C. iii.
124, pi. v. figs. 5-8 ; T. Sfrefhill Wright, Edin. N. Phil.
Journ. for Jan. 1858, 108, pis. i. and ii.

WIUGHTIA ACUMINATA, Affassi^, N. II. U. S. iv. 354.

Plate XXXVII.

STEM slender, more or less branched, annulated, the annu-
lations strongest at the base and becoming fainter or
disappearing towards the calycle ; branches given off a
little below the calycles, and copies of the primary shoot ;
HYDROTHECJE thin, membranous, finely striated longitu-
dinally, elongate pod-shaped, squared below and tapering
to a fine point above; GONOTHEC.E very large, cylin-
drical, smooth, supported on long peduncles, developed
on the steins, generally near the base, or on the stolon ;
POLYPITES very extensile, with about 20 muricated ten-
tacles, united for about ^ of their length by a mem-
branous web.

GONOZOOIDS pale-emerald green*; UMBRELLA subhemi-
sphericai, becoming mitrate during contraction, covered
with large thread-cells, more especially about the middle
and upper parts ; MANUBRIUM quadrangular ; TENTA-
CULAR BULBS ringed with deep-blue, destitute of ocelli.

VAN BENEDEN was the first to examine and figure this
interesting form, so long ago as 1847. He named it Cam-
panulina tenuis, constituting a new genus for its reception,
and taking the web which unites the basal portion of the
tentacles as the principal distinctive character. He gives,
however, no detailed description, and his figure does not
enable us to recognize the species which he had in view.
Mr. Alder has determined its identity with his OAvn Lao-
medea acuminata from an examination of specimens trans-

* "Aussi belles de couleur quelcs plus belles emeraudi's." -— Vu»

188

CAMPANTJLINID^.

mitted by Van Beneden. While the Belgian naturalist's
genus is retained, there can be no doubt that Alder's spe-
cific name is entitled to precedence, as he has given us the
first full diagnosis and an admirable figure. Dr. Strethill
Wright's valuable observations on the reproductive zooid
complete the history of this species.

Mr. Alder remarks that the polypite, ' ' when extended,
stretches far beyond the cell, the latter adhering closely
to it and becoming cylindrical;^ it frequently changes
form. The tentacles are alternately elevated and de-
pressed, so as to form two circles. The beautiful web
which unites their bases is "studded with thread -cells of
very large size, ranged along each side of the tentacles 'J
(Wright). (Woodcut, fig. 21.) The stem is sometimes

Fig. 21.

simple, bearing a single polypite only; but in other
cases it is repeatedly branched, and "is transformed
into a more or less bushy shrub, covered with polypites,
and rarely bearing a large Medusa-bud, which is generally
developed from the first stem" (Wright}. The hydro-
theca is extremely membranaceous and yielding, becoming

CAMPANULINA REPENS. 189

still more delicate towards the top, where it collapses and
is folded together and creased so as to form a conical apex,
which serves the purpose of an opei'culum. Mr. Alder
describes the margin as slightly crenulated. I believe,
however, that there is no true crenulation, but that the
appearance is due to the points formed by the folds of the
membrane.

The capsules make their appearance, according to Van
Beueden, in the month of June. I have only seen C. acu-
minata alive in an aquarium, where it covered profusely
a deserted univalve shell ; and I have seldom witnessed a
more remarkable display of Hydroid beauty.

Hob. On an old shell of Fusus antiquus from deep water,
Cullercoats (J. A.): on an old oyster-shell from the Firth
of Forth (T. S. W.).

[Coast of Belgium, on shells, stones, and wreed (Van
Beneden) .]

2. C. REPENS, Airman.

" Notes on the Hydroida," Ann. N. H. for July 1864.

Plate XXXVIII. fig. 1.

STEM simple or branched, distinctly annulated, branches
alternate; HYDROTHEC.E conical, closed by a membra-
nous operculum, formed of deep and acute convergent
segments ; GONOTHEC^E large, obconic, slightly gibbous
at one side near the base, with a short ringed stalk,
borne on the creeping stolon and occasionally on the
stem; POLYPITES very extensile, with about 16 tentacles
alternately elevated and depressed, and united at the
base by a very shalloio web.

GONOZOOID (at the time of liberation) with four very ex-
tensile tentacles, which are nodulated by clusters of
thread-cells.

THIS species differs from the last in the following parti-

190 CAMPANULINID^E.

culars : — Its calycle is " crowned by long converging seg-
ments, which on the retreat of the polypite form a true
operculum," while in C. acuminata it is merely " continued
by a delicate, collapsile, and undivided membrane ; " the
web that unites the bases of the tentacles is much more
slightly developed ; and the gonozooid has four tentacles,
instead of two, at the time of its escape from the capsule.
Hob. Investing the surface of Sertularian Hydroids
from about 5 fathoms in the Firth of Forth (G. J. A.).

3. C. TURRITA.
Plate XXXVI. fig. 2.

STEM distinctly ringed throughout, somewhat zigzagged,
bearing short, annulated ramules in groups of two or
three at every bend, each of them supporting a polypite ;
HYDROTHEC^E tall and slender, widening gradually up-
wards from the base, with an operculum composed of
short, convergent segments ; GONOTHEC JE broad and sub-
truncate above, bulging slightly at one side, tapering
downwards, shortly stalked, and borne on the stem.

GONOZOOID closely resembling that of C. acuminata.

I AM only able to give an imperfect account of this very
pretty species, as I have not had the opportunity of ex-
amining specimens. It differs notably from C. repens in
the shape of the calycles. The segments composing the
operculum are very much shorter in proportion to the
length of the hydrotheca than in the latter species. In
C. repens they are deep and form a tall, acuminate
covering, which is about a third as long as the calycle ; in
C. turrit a the striking feature is the disproportion between
the latter and the shallow operculum. The general habit
and the grouping of the ramules also differ in the two
forms.

ZYGODACTYLA. 191

The gonozooid of C. turrita, as I learn from Professor
Wyville Thomson, who has kindly supplied me with the
drawing on which this description is founded, resembles
that of C. acuminata so closely that it is difficult to distin-
guish the one from the other. It is slightly broader in its
proportions and perfectly colourless. The umbrella is
dotted over with large thread-cells.

Hab. Very abundant on Zostera (along with Campanu-
laria angulata], Holy wood, Belfast Lough (Prof. W.
Thomson) .

Genus ZYGODACTYLA, Brandt.

JEQroEEA, Peron and Lesueur (in part).
RHACOSTOMA, Agassiz.

GENERIC CHARACTER. — Stem simple or branching, rooted
by a filiform stolon ; hydrothecce with an operculum formed
of many convergent and acuminate segments; polypites
cylindrical, with the tentacles ivebbed below. Reproduction
by free medusiform zooids.

Gonozooid : Umbrella (in the adult] more or less hemi-
spherical ; manubrium short, ivith many fimbriated lips ;
radiating canals very numerous; marginal tentacles very
numerous, with bulbous bases ; lithocysts borne on the
margin of the umbrella.

THE medusiform sexual zooids of several Zygodactyla;
are known, but in one case only has the polypite been ob-
served. The gonozooids are remarkable for their size;
those of Z. Grcenlandica (A. Agass) sometimes measure as
much as fifteen inches in diameter ; those of Z. crassa, of
the same author, are nearly as large.

The number of radiating canals in the adult is very great
(about 100) ; they are progressively developed; and in very
young specimens, according to the observations of A.

192 CAMPANULINLD^E.

Agassiz, only four are present. They are developed from
the digestive cavity, and gradually extend downwards,
opening at last into the circular vessel. Sometimes two
or three rudimentary tubes of various lengths are met
with between each of the perfect canals. The fimbriated
mouth of the manubrium is a striking feature; indeed
the whole structure is complex, and there is an extra-
ordinary multiplication of parts. It is curious that the
only one of these comparatively gigantic organisms that
has been traced to its stock should prove to be the repro-
ductive phase of one of the smallest of the Hydroida.

Though there is so much superficial difference between
the adult gonosomes of Campanulina and Zygodactyla,
there can be little doubt that these genera should be
ranked in the same family. The trophosomes are identical ;
and in their earliest condition there seems to be no essen-
tial difference between the gonozooids. Those of Zygo-
dactyla have probably only four radiating canals at the
time of liberation, the number increasing, like that of the
tentacles, as they advance to maturity. In Campanulina
the arms multiply, but the canals seem never to exceed four.

Z. VITRINA, Gosse.

^EQUOREA VITRINA, Gosse, Devonsh. Coast, 340, pl.xxiii. ; T. S. Wright, Journ.

of Micr. Science, iii. (N. S.) 45, pi. iv. figs. 1-6.
ZYGODACTYLA VITRINA, Agassis, N. H. U. S. iv. 361.

Plate XXXVIII. fig. 2.

STEM simple (or branched?); HYDROTHEC/E squared below,
and above terminating in many convergent segments;
POLYPITES with 12 alternating tentacles, united for about
a third of their length by a web ; GONOTHEC.E unknown.

GONOZOOID. — UMBRELLA hemispheric or subconic, perfectly
colourless ; MANUBRIUM wide, traversed by opake white
lines, and with very numerous, narrow, pointed, furbe-

OPERCULARELLA. 193

lowed and reflexed lips,, reaching almost to the margin
of the umbrella ; RADIATING CANALS 80-90 ; MARGINAL
TENTACLES white, attenuated, with small bulbs at the
base, extremely numerous (as many as 400 iiithe adult);
LITHOCYSTS with from two to five refractile spherules.

THE polypites have only been observed in their earliest
stages of growth, and we are ignorant what the perfect
form may be. Dr. Wright, having procured specimens of
the sexual zooid (the JEquorea vitrina, Gosse), succeeded
in hatching the ova, and tracing the development of the
planules into extremely minute polypites, which he could
not distinguish from the hydroid phase of Campanulina
acuminata. They were quite invisible, however, to the
naked eye, and in too immature a state to allow of satis-
factory examination.

The goiiozooid attains a very large size, being sometimes
as much as about six inches and a half in diameter. Mr.
Gosse's specimens were much smaller, and only partially
developed. The oral lobes and the marginal tentacles,
with their attendant lithocysts, in the examples which
came under his notice, were much less numerous than in
the adult. The latter numbered more than 200, and the
former about 20 ; while in the older individuals examined
by Wright there were no less than 400 tentacles and 40
lobes. The umbrella is perfectly translucent, and the
radiating canals are described as resembling "bands of
frosted or ground glass upon a body of clear glass."

Hub. Ilfracombe (Gosse) : Scotland (T. S. W.).

Genus OPERCULARELLA, Hincks.

Der. A diminutive form of Opercularia, from Operculum, a lid.
GENERIC CHARACTER. — Stem simple or branching, rooted
by a thread-like stolon ; hydrothecce ovato- conic, with a cleft
border, the segments of which conrcrt/e to form <ni o

o

194 CAMPANULINID^E.

polypites long, cylindrical, and with a conical proboscis ; re-
production by means affixed sporosacs, which (in the female)
become extracapsular before the escape of the planules.

THIS genus is constituted for the Campanularia lacerata
(Johnston), which is identical with Campanulina, so far as
the trophosome is concerned, but differs from it widely in its
mode of reproduction. Allman ranks it along with C.syringa
(Johnston) under the genus Calycella ; but though these
two forms are similar in some respects, their calycles are
formed upon a different type, those of C. syringa allying it
with Lafoea, and those of C. lacerata with Campanulina.

The operculum of the present genus differs from that of
Calycella ; it is nothing more than the cleft border of the
hydrotheca, which collapses and forms a kind of roof. In
Calycella it consists of a true lid — a turreted covering or a
folded membrane. There is indeed a striking dissimilarity
between the hyaline, ovato-conic calycles of Opercularella,
and the long, tubular calycles, of somewhat dense texture,
which distinguish the true CalycellcE ; and the points
which separate the present genus from the Lafoeidcs
connect it with Campanulina. I believe, therefore, that
the natural relationships will be best represented on the
whole by the arrangement which I have adopted.

O. LACERATA, Johnston.

CAMPANULARIA LACERATA, Johns? . B. Z. Ill, pi. xxviii. fig. 3; Van Beneden,
Faune Litt, de Belgique, Polypes, 159, pi. xv. fig. 5-13.

CAPSULARIA LACERATA, Gray, Cat. B. M. Eacliata, 87.

LAOMEDEA LACERATA, Hincks, Ann. N. H. (2nd ser.) x. 86; T. 8. Wright,
Edinb. N. P. Journ. (N. S.)for Jan. 1859, pi. iii.

WRIGIITIA LACEKATA, Agassiz, N. H. II. S. iv. 354.

CALYCELLA LACERATA, Allman, Ann. N. H. for May 1864, 31.

Plate XXXIX. fig. 1.
STEM erect, slender, slightly flexuous, annulated throughout,

OPERCTJLAKELLA LACERATA. 195

sparingly branched; HYDROTHEC^ on short ringed pe-
dicels, alternate, ovato-conical, the operculum composed
of deep, convergent segments ; GONOTHEC^E (female)
large, ovate, smooth, on short, ringed stalks, produced
near the calycles ; (male) subcylindrical.
Height, when mature, from ^ to 1^ inch.

THIS species is commonly found in very humble guise, the
creeping stem sending up at intervals short, ringed stalks,
which bear a single calycle. In this state it occurs pro-
fusely on stones, shells, seaweeds, and other zoophytes.
I have a specimen of this form from Torbay, covering the
inner surface of a shell, in which the reproductive capsules
are produced on the creeping stolon amongst the calycles.
In its most highly developed state O. lacerata is either
bushy or of tall and slender growth ; its usual height is
about half an inch.

The gonothecae are produced abundantly ; the female
are surmounted at a certain stage by a large and conspi-
cuous sac, enclosed in a thick gelatinous envelope, and
containing a brood of several planules*. The polypites
have about fourteen arms, are slender and graceful, and
extend themselves far beyond the top of the calycle.

Hab. Between tide-marks and in moderate depths ; not
uncommon. St. Ives, Cornwall; Exmouth, in tufts of
Bowerbankia ; Ilfracombe ; Isle of Man ; Filey, Yorkshire
(T. H.) : Northumberland (J. A.): Morrison's Haven, Firth
of Forth, in profusion (T. S. W.): St. Andrew's (J. Reid):
Oban (T. H.): North of Ireland (Prof. W. Thomson).

[Coasts of Belgium (Van Beneden).]

* Dr. Wright was the first to describe the reproductive zooids. Vide
Edinb. New Phil. Journ. (N. S.) for Jan. 1850.

O

O

196 LEPTOSCYPHHXE.

Family III. — Leptoscyphidse.

HYDROTHEC^E ovato-conic ; POLYPITES cylindrical, ivith a
conical proboscis ; GENERATIVE ELEMENTS produced in
the walls of the manubrium ; LITHOCYSTS wanting.

Genus LEPTOSCYPHUS, Allman.

Der. from XeTrros, delicate, and CTKU^OS, a cup.

GENERIC CHARACTER. — Stem single or branching, at-
tached by a thread-like stolon ; hydrothecce with an oper-
culum composed of convergent segments; polypites cylin-
drical, with a conical proboscis ; reproduction by free
medusiform zooids.

Gonozooid: Umbrella (at the time of liberation] deep
bell -shaped or conical; manubrium of moderate size, pen-
dent from a conical projection from the roof of the umbrella,
the mouth with four short capitate tentacles ; radiating
canals 4>, each terminating in a bulb without ocellus, bearing
a cluster of two or three tentacles ; a single marginal ten-
tacle with a bulbous base in each interradial space ; litho-
cysts wanting.

THE gonozooid of this remarkable genus is identical
with the Lizzia of Forbes ; the trophosome is that of the
Campanulinida. Now the genus Lizzia is one that pro-
duces the generative elements in the walls of the manu-
brium, a situation in which they never occur amongst the
Thecaphora, except in this single instance. If Allman is
right in referring to his Leptoscyphus the medusiform
zooids which he found free in the phial containing it, the
present genus stands alone in the suborder.

Claparede has found a Lizzia in the development of

LEPTOSCYPHUS TENUIS. 197

which the fixed-poly pite element is wanting, and the ova
give origin directly to the medusa or natatory polypite ;
and Allman proposes to retain Forbes' s name for this type.
The tentacles of the free zooid of Leptoscyphus probably
increase in number with age, until each of the eight mar-
ginal bulbs bears a cluster of them (Woodcut, fig. 22) *.

Fig. 22.

Uzzia grata (A.. Agass.)

In the Lizzies observed by Sars and Forbes, gemmation
took place from the walls of the manubrium.

Leptoscyphus is placed in a distinct family on account of
the remarkable peculiarities of its gonosome.

L. TENUIS, Allman.

LAOMEDEA TENUIS, Allman, Ann. N. H. for Nov. 1859.

LEPTOSCYPHUS TENUIS, Allman, On the construction and limitation of Genera
among the Hydroida, Ann. N. H. for May 1864.

Plate XXXIV. fig. 2.

ZOOPHYTE minute ; STEM geniculate, distinctly annulated ;
HYDROTHEC^: with a deeply cleft margin, borne on ringed

* The woodcut represents an adult Lizzia : the interradial clusters are
smaller than those at the extremity of the radiating canals.

198 LAFOEID^.

pedicels having the same diameter as the stem, and spring-
ing alternately from the bends ; GONOTHEC^: large, cylin-
drical, with the lower end conical, and the upper broad
and truncated, containing a single zooid.

POLYPITES very extensile, with 16 or 18 tentacula.

GONOZOOID. See the description under the generic cha-
racter.

THE tentacles of the gonozooid have the thread-cells uni-
formly distributed over the surface, showing no tendency
to an arrangement in distinct groups.

Hub. On the fronds of Laminaria digitata, from about 3
fathoms water, off the town of Stromness (G. J. A.).

Family IV. — Lafoeidae.

HYDROTHEOE tubular ; POLYPITES cylindrical, with a coni-
cal proboscis.

Genus LAFOEA, Lamouroux.

Der. Named after M. de Lafoye, a botanist and Professor of Matheinaties
in the College of Aler^on.

CALICELLA, Hincks (in part).

GENERIC CHARACTER. — Stem a simple, creeping, tubular
fibre, or erect and composed of many tubes aggregated to-
gether, rooted by a filiform stolon; hydrothecae tubular,
sessile or with a short pedicel, without an operculum, more
or less regularly disposed on the stem and branches ; poly-
plies cylindrical, with a conical proboscis.

Reproduction unknown.

THE section of Johnston's Campanularia including the
smaller species with tubular and somewhat densely cor-

LAFOEA. 199

neous calycles, which are slightly, if at all, pedunculate,
differs widely from the forms with which he associated it.
To Lamouroux belongs the credit of having first recognized
as distinct the type of structure which it exhibits. His
Lafoea was founded (in 1812) 011 an American species
(L. cornuta} which closely resembles the well-known L.
dumosa, and may be identical with it. The genus, how-
ever, was lost sight of until, in 1862, it was restored by
Sars. In the meantime I had constituted the genus
Calicella for the Campanula/rice with tubular calycles, in-
cluding under it both the operculated and inoperculated
forms. This name, of course, must give way to Lafoea, so
far as one section of the group is concerned ; but as I have
decided to form the species with an operculum into a sepa-
rate genus, I retain it for them.

It is a remarkable fact that as yet no observations have
been made that throw any light on the reproductive history
of the present genus. This is the more extraordinary as the
species are profusely developed, and L. dumosa is one of the
commonest and most widely distributed of the Hydroida.
Amongst some thousands of specimens, examined from
time to time, I have never met with any trace of repro-
ductive bodies. Sars records a similar experience*.
Agassiz, indeed, has referred a medusiform zooid observed
by his son to the Lafoea cornuta of Lamouroux ; but we
learn from A. Agassiz, in his ' Catalogue of North Ameri-
can Acalephse/ that this is a mistaken identification.

Of course, the present definition of the genus Lafoea
can only be regarded as provisional. It is quite possible
that more than one type may exist amongst the species
that are ranged under it.

* " Beuiaerkninger over firenorske Hydroida," Videnskab. Porhandlinger,
1862.

200 LAFOEID.E.

1. L. DUMOSA, Fleming.

SERTULARIA VOLUBILIS/?, Pallas, Elench. 123.

„ DUMOSA, Fleming, Edinb. Phil. Journ. ii. 83.

TUBULARIA TUBIFERA, Johnst. Edinb. Phil. Journ. xiii. 222, pi. iii. figs. 2, 3.
? LAFOEA CORNUTA, Lamx. Expos. Meth. 5, pi. Ixv. figs. 12, 14.
CAMPANULARIA DUMOSA, F/em. Brit. An. 548; Johnst. B. Z. 113, pi. xxvii.

figs. 2, 5.

CORNULARIA DUMOSA, Couch, Zooph. Cornw. 39.
,, RUGOSA, Gray, Ann. N. H. i. 238.

CAPSULARIA DUMOSA, Gray, Cat. B. M. Radiata, 88.
CALICELLA DUMOSA, Hincks, Cat. Dev. & Cornw. Zooph. 23 ; Ann. N. H.

(3rd ser.) viii. 293.
LAFOEA DUMOSA, Sars, Videnskab. Forhandl. 1862; Allman, Ann. N. H. for

May 1864.

Plate XLI. fig. 1.

STEM simple and creeping, or erect and irregularly
branched, both stem and branches being composed of
several parallel tubes; HYDROTHEC.E long, stout, nar-
rowed towards the base, sessile, with a plain aperture,
springing from all sides of the stem and branches; GO-
NOTHEC^E unknown; POLYPITES of a sulphur-yellow
colour.

Var. a. robust a (Sars). More robust, thickly branched,
with more numerous calycles, which are densely crowded
together.

Var. /3. With smaller calycles and a simple stem, which is
attached at intervals only to other zoophytes, hanging
from them in a festooned fashion. (Alder.}

Height of erect form from 2 to 4 inches.

L. DUMOSA is subject to many variations in habit, in the
size of the calycles, in the thickness of the compound stem,
the amount of branching, &c. In its humbler or dwarf
condition it is met with in immense profusion, covering the
stems of other zoophytes, running over the surface of sea-
weeds, or investing shells and stones with its delicate net-
work and tinv tubes.

LAFOEA DTJMOSA.

201

Fig. 23.

The erect form rises into bushy tufts. The calycles are
of stout, firm material, and retain their shape when dried ;
they are sometimes distant, sometimes crowded together
on the upright stem and branches.

The variety robusta (Woodcut, fig. 23) was at one time
regarded by Sars as a species ;
but he subsequently changed
his opinion, on finding a form
intermediate between it and
the normal dumosa.

The stems are composed of
more numerous tubes than
in the common form, and the
calycles are somewhat shorter
and thicker.

I have obtained this very
striking variety, which was dredged by Sars near the North
Cape in 30-50 fathoms, from the Coast of Cornwall. It
has a very distinctive habit of growth.

The whole of the ccenosarc in L. dumosa, as well as the
polypite, is of a delicate sulphur-colour.

Hab. On various marine bodies from the littoral region
to very deep water : very common and generally distri-
buted. Dredged by Capt. Beechey, off the Mull of Gallo-
way, in 145 fathoms, and the only hydroid found at this
depth.

[Coasts of Norway (Christiania, Bergen, &c.)(Sars): (var.
robusta) North Cape, 30-50 fath. (Sars): Labrador, Cateau
Harbour, Long Island, not common (A. S. Packard, jun.) :
Nova Scotia (teste A. Agassiz) : Massachusetts Bay (A.
Agassiz) .]

202 LAFOEID^E.

2. L. FRUTICOSA, Sars.

CAMPANULAUIA FRUTICOSA, Sars, Eeise i Lofoten og Finmarken, 18 ; Nyt Ma-

gaz. f. Naturvid. 1850, 6 B. 138.
„ GKACILLIMA, Alder, North, and Durh. Cat. in Trans. Tynes.

F. C. iii. 129, pi. vi. figs. 5, <>.
CALICELLA FRUTICOSA, Hincks, Devon and Cornw. Cat., Ann. N. H. (ser. 3)

viii. 293.
LAFOE.V FRUTICOSA, Sars, Benuerkn. over fire norske Hydroid., Videnskab.

Forhandl. 1862.

Plate XLI. fig. 2.

STEM erect,, compound, irregularly and often subunila-
terally branched; HYDROTHEC.E very slender, long, with
an entire aperture, of a thin and fragile material, borne
on short pedicels, ivith 3 or 4 rings, or loosely twisted and
with two whorls; GONOTHECJE unknown.

Height (when finely grown) about 3 inches.

As compared with L. dumosa this species is eminently
delicate and fragile. It grows in shrubby tufts, and, when
living, is of a light yellow or citron-colour. The calycles
are distinctly stalked ; they are much narrowed below, and
a little above the base curve outwards on one side,
and are slightly concave at the opposite point : this gives
them a somewhat crooked appearance. The calycles of
L. dumosa are much straighter and stouter ; they are also
of denser texture and sessile. The present species is made
of much more delicate material than its sturdy ally, and,
when dried, sorely disappoints the collector, the calycles
shrivelling up and the specimen losing its beauty.

I have identified the L. fruticosa (Sars) and the L. gra-
cillima (Alder), though not without some doubt. They
differ chiefly in the character of the pedicel, which in the
former is distinctly ringed, and from one-third to half the
length of the calycle, while in the latter it is loosely twisted,
" making about two turns " and not more than one-fourth
the length of the calycle. The hydrothecre also are

LAFOEA PARVULA. 203

commonly longer and thinner in the British than in the
northern form. Sars describes the polypite of his fmti-
cosa as " white or ash-coloured; " but that of gracillima, as
observed on beautiful specimens procured at Oban, where
the species occurs in great luxuriance, is citron-coloured.
If these differences should prove to be constant, it may be
necessary to separate the northern from the British form,
and to retain the two names. Authority is pretty well
balanced on the point. Sars is inclined to regard them
as distinct ; Alder considered them identical.

Hub. On shells, zoophytes, &c. Northumberland and
Durham (from deep water) occasionally (J. A.): Oban Bay
(in 15-20 fathoms), very fine and abundant (T. H.): Shet-
land (A. M. N.): South Devon (J. A.).

[Common near Bergen in 30-50 fath., especially where
there is a strong current ; Tromso, rarer ; North Cape,
extremely abundant (40-50 fathoms) in a strong current,
on rocky ground (Sars): coast of Iceland, in 100 fathoms
(the northern form) (T. H.).]

I have examined the Lafoea from Bass's Straits in Mr.
Busk's collection, referred to by Alder (North. & Durh.
Cat.), and have little doubt that it is identical with the pre-
sent species.

3. L. PARVULA, Hincks.

" Further notes on British Zoophytes," Ann. N. H. for March 1853, (ser. 2)
xi. 178, pi. v. A.

Plate XL. fig. 1.

STEM creeping; HYDROTHEC.E very minute, cylindrical,
broad (width considerably more than half the lengtli],
rounded off below, with an entire aperture, borne on
short, ringed stalks (4 rings]; GONOTHEC^E unknown.

THE creeping stem is of great delicacy, and forms a rude

204

LAFOEID.E.

Fig. 24.

kind of network. The calycles are
exceedingly minute, and of equal
width throughout, till within a short
distance of the base, when they are
abruptly rounded off; they are of a
somewhat dense corneous texture,
and preserve their shape well when
dried (Woodcut, fig. 24).

Had. On Nitophyllum from the
north of Ireland (Professor Hincks,
University College, Toronto).

4. L. POCILLUM.

Plate XL. fig. 2.

STEM creeping; HYDROTHEC^E minute, tumid beloiv, with
the sides curved inwards above, and expanding again
slightly towards the top, aperture entire, borne on rather
long, ringed pedicels ; GONOTHECLE unknown.

THE very graceful outline of the calycle distinguishes this
species from all the other British members of its genus,
amongst which the prevalent form is cylindrical or simply
tubular. It resembles a very elegant little goblet mounted
on a twisted stem. In the hydrotheca of L. pocillum the
lower half is the widest portion ; above it the sides are
incurved, but they expand again towards the aperture.
The length of the pedicel varies ; it usually consists of 6
or 7 rings, but is occasionally longer.

Hab. Oban Bay, creeping over a seaweed (T. H.).

[Hamilton Inlet, Labrador (15 fathoms), on weed (teste
T. H.).]

CALYCELLA. 205

5. L. FYGMjEA, Alder, MS.

Plate XL. fig. 3.

STEM creeping; HYDROTHEC.E very minute, cylindrical,
elongate and narrow, of a yellowish horn-colour, borne
on very short, ringed pedicels (2 or 3 rings}; GONOTHEC^E
unknown.

THIS form was discovered by the late Mr. Alder, and named
by him in manuscript, but never published. It is extremely
minute ; the calycle is a narrow cylinder rounded off below
and borne on a very short pedicel. In some of Mr. Alder's
figures there are traces of a slight and shallow operculum ;
but I have not been able to distinguish one in the speci-
mens which I have examined, and must leave it to other
observers to decide the point. If it be an operculated
species, it must be transferred to the following genus.

Hab. Tynemouth (J. A.): Gouliot Caves, Sark, in pro-
fusion (A. M. N.).

Genus CALYCELLA, Hincks (in part).

Der. A diminutive formed from K«\JI£, a cup.
CAMPANULARIA, Lamark (in part).

GENERIC CHARACTER. — Stem a creeping tubular fibre, or
erect, compound, and branched, rooted by a filiform stolon ;
hydrothec<e tubular, with an operculum formed of convergent
segments or a plaited membrane ; polypites cylindrical, with
a conical proboscis. Reproduction by means of fixed sporo-
sacs, which (in the female] become extracapsular before the
liberation of the ova.

THIS genus, as originally constituted*, had a much wider

* "Cat. of South Devon and Cormv. Zooph.." Ann. N. H. (.'3rd ser.) viii.203.

206 LAFOEED^E.

range, and included those Campanularian species of which
the C. dumosa (Fleming) is the type. The restoration of
Lamouroux's name (Lafoea) for the latter group renders
it necessary to define Calycella anew ; and I now restrict
it to the operculated forms, of which Campanularia syringa
(Linnaeus) may be taken as the type.

1. C. SYRINGA, Linn.

" CREEPING BELL CORALLINE," Ellis, Corall. 25, pi. xiv. fig. b, B.
SERTULARIA SYRINGA, Linn. Syst. 1311.

„ VOLUBILIS, Pall. Blench. 122.

„ REPENS, Ellis $ Soland. Zooph. 52.
CLYTIA SYRINGA, Lamx. Cor. flex. 203.
CAMPANULARIA SYRINGA, Lamk. An. s. Vert. (2nd eel.) ii. 132; Van Bencde/i,

Camp. 37, pi. iii. fig. 9; JoJmst. B. Z. 110, woodcut 19.
CAPSULARIA SYRINGA, Gray, Cat. B. M. Eadiata, 86.
CALICELLA SYRINGA, Hincks, Cat. Devon Zooph. 23 ; Ann. N. H. (3rd ser.)

viii. 294 ; All-man, Ann. N. H. for May 1864.
WRIGIITIA SYRINGA, Agassis, N. H. U. S. iv. 354.

Plate XXXIX. fig. 2.

STEM creeping, smooth; HYDROTHEC^E of a dark horn-
colour, cylindrical, rounded off below, with a slightly
sinuated margin, which is prolonged above into an oper-
culum composed of 8 or 9 segments, borne on twisted
pedicels of variable length, but with not less than three
or four whorls ; GONOTHEC^E oval, smooth, with short,
ringed stalks (1 or 2 rings), distributed amongst the
calycles.

THE rim of the hydrothecre in this species is always
described as perfectly plain ; and so, on a first inspection, it
appears to be. But a careful examination with the micro-
scope shows that it is very slightly sinuated, rising at
intervals into minute points, between which are extremely
shallow depressions corresponding with the segments of

CALYCELLA SYRINGA. 207

the operculinn. The latter is often connected with a
curious piece of structure.

It consists of a membranous tube or sheath, which rises
to a greater or less height above the true margin of the
calycle, and terminates in a serrated border. Within this
sheath, and at the base of the denticulated edge, the oper-
culum or lid is placed, composed of several converging
segments, Avhich fit closely together and constitute a
conical roof to the little dwelling below. The crenated
margin of the sheath, which is extremely delicate, rises
above the top of it, and forms an ornamental border
round it.

This structure is only met with on some of the calycles,
and is so minute and delicate that it requires a high power
and careful manipulation to master its details. It is a
later growth, and is developed on the older hydrothecse.
The lid is sometimes drawn within the calycle and reversed,
so as to exhibit the figure of an inverted cone.

The pedicel of C. syringa is of very various length, but
when shortest has three or four rings (or spiral twists).
The texture of the calycles is somewhat densely corneous,
and they are generally of a deep horn- colour.

The acrocyst or external marsupium, in which the ova
pass through the later stages of their development, is a
spherical sac with a gelatinous covering, that rests like a
ball on the summit of the capsule *.

The polypite has about sixteen arms.

Hab. On other zoophytes and on seaweeds ; very com-
mon.

[Off Reikiavik, Iceland, in 100 fathoms (T. H.).]

* "Notes on the Reproduction of the Campanulariadse," by the Rev. T.
Hincks, Ann. N. H. for August 1852.

208

LAFOEIDyE.

2. C. FASTIGIATA, Alder.

CAMPANULARIA FASTIGIATA, Alder, Ann. N. II. for February 18(30.

Plate XXXIX. fig. 3.

STEM creeping, smooth, closely adherent; HYDROTHEC.E
large, oblong, tubular, gradually tapering off below into
a pedicel, which is smooth and of variable length, — above
" rising into two opposite points, between which a plaited
membrane on each side slopes over the aperture, forming
an operculum with a medial ridge"*; GONOTHEC.E un-
known.

Height of calycle ^ inch.

ALDER has pointed out the resemblance of the remarkable
operculum with which this species is furnished to the roof
of a house, " the two opposite angles forming the gables."

The pedicel is commonly about a third of the length of
the calycle, but sometimes
much longer. It exhibits
no trace of annulation.

The Lafoea plicatilis of
Sarsf (Woodcut, fig. 25)
resembles this species in
the structure of the oper-
culum, but is otherwise dis-
tinct. It belongs to the
present genus rather than
to Lafoea.

Hob. On the stem of a Eudendrium from the inner
Hauf, Shetland (Barlee): the Hebrides (A. M. N.): on
Plumularia tubulifera &c. from Cornwall (T. H.).

* Alder.

f " Bemrerkninger over fire norske Hydroida," Videnskabs. Forhandl.
1862. He describes the gonothecw of L. pJicafiUs, which are very long and
cylindrical, and contain many gonophores ; but he has not observed the
development of the sexual zooids.

CUSPIDELLA HUMILIS. 209

Genus CUSPIDELLA, Hincks.

Der. Diniin. formed from ctispis, a point.

GENERIC CHARACTER. — Stem creeping, filiform ; hydro-
theca cylindrical or subcylindrical, perfectly sessile, with a
conical operculum composed of many pieces; polypites
cylindrical, with a conical proboscis.

Reproduction unknown.

IN this genus there is no trace of a pedicel or erect stem ;
the calycles are not constricted towards the base, but are
open cylinders to the point of junction with the creeping
fibre.

When it was first constituted, only a single species was
known ; but I have since met with two more, in which the
typical characters are well represented. All the species
are exceedingly minute.

1. C. HUMILIS, Hincks.

CAMPANULARIA HUMILIS, Hincks, MS. ; Aider, Suppl. North. & Durh. Cat, in

Trans. Tynes. F. C. v. 230.

CALYCELLA? HUMILIS, All man, Ann. N. H. for May 1864.
CusriDELLA HUMILIS, Hincks, Ann. N. H. for October 1866.

Plate XXXIX. fig. 4.

STEM very delicate; HYDROTHEC^E subcylindrical, rather
stout and short, the upper portion divided into 10 or 12
convergent segments, which form an operculum; GONO-
THEC.E unknown.

THE calycles of this curious and very minute species are
like little cylinders rising directly from the creeping stem ;
occasionally they expand slightly upwards. The oper-
culum is sometimes drawn within the calycle, as in the
case of Calycella syringa.

210 LAFOEID^E.

Hab. On tlie stems of zoophytes. Llandudno, North
Wales; Whitby; Shetland (T. H.) : Northumberland,
"on other zoophytes from deep water, occasionally "(J. A.).

2. C. GRANDIS.
Plate XL. fig. 4.

HYDROTHEC^E cylindrical, slender, much elongated, some-
times curved, with an operculum composed of fewer and
larger segments than in the last species ; GONOTHEC^E un-
known.

Height of calycle about twice as great as in C. humilis.

THIS species differs from the preceding chiefly in the pro-
portions of the hydrothecse, which are narrow and com-
paratively gigantic; those of C. humilis are dwarfish,
and broad in proportion to their height. In the present
species the Avidth is only about £ or ^ of the height ; in
the last it is about \ or ^ of it. There are also differences
between the two forms in the operculum.

Hab. Birterbuy Bay, Connemara (G. S. Brady): Shet-
land (J. A.).

3. C. COSTATA.
Plate XL. fig. 5.

HYDROTHECLE somewhat broadly cylindrical, encircled by
two or three rather prominent ribs, or lines of growth,
dividing them into ser/ments, the uppermost or opercular
segment formed of thinner material than the rest, and
supporting a conical operculum, composed of very nu-
merous convergent pieces ; GONOTHEC^E unknown.

THE calycle of C. costata is generally divided into three
segments, besides the uppermost. The latter is a delicate

SALACIA. 211

and half-membranous continuation of the walls of the
hydrotheca, and is crowned by a very beautiful operculum,
which is capable, as in several allied forms, of being re-
tracted within the cylinder. The transverse rings or ribs
mark the periods of growth. The present species is very
minute.

Hab. On Syncoryne eximia, Whitby, Yorkshire (T. H.).

Genus SALACIA, Lamouroux* .

GRAMMARIA, Stimpson, Marine Invertebrate of Grand Manan, 9.

GENERIC CHARACTER. — Stem erect, composed of aggre-
gated tubes, branching, rooted by a filiform stolon (?); hy-
drotheca cylindrical, sessile, without operculum, adnate for
the greater part of their length, disposed on all sides of the
stem and branches in regular and equidistant longitudinal
series ; gonothecce scattered on the stem and branches ;
gonophores unknown.

Polypites long, cylindrical, with a conical proboscis.

THE Salacia of Lamouroux, founded on an Australian
Hydroid (S. tetracyttara], is identical in all essential par-
ticulars with the Grammaria of Stimpson, and I have
therefore restored his name. In Lamouroux's species the
stem is much compressed, and the apertures of the hydro-
thecae are on a level and scarcely project, but in other
respects it closely resembles the American and British
form.

Salacia is very nearly related to Lafoea. The principal
difference between them is to be found in the disposition
of the calycles : in the latter genus they are irregularly
distributed ; while in the former they are arranged on a

* Polypes Flex. Corallig. p. 214; Exposition Methodique. p. 1.~>.

212 LAFOEID^E.

definite plan, and form regular, longitudinal rows. In
Lafoea they are free throughout their entire length, and
patent ; in Salacia they are in great part adnate.

Sars has pointed out that in the present genus the hy-
drothecae are not separated from the stem by any constric-
tion, and that the polypites when contracted can withdraw
themselves wholly from them into the tube of the stem.

S. ABIETINA, Sars.

CAMPANULARIA ABIETINA, Sars, Eeise i Lofoten og Finm., Nyt Magaz. f.

Naturvid. 1850, 139.
GRAMMARIA ROBUSTA (young), Stimpson, Marine Invert, of Grand Manan, 9,

tab. i. fig. 3.
,, RAMOSA, Alder, Cat. of North, and Durh. Zooph. in Trans. Tynes.

F. C. iii. 130, pi. iv. figs. 1-4 ; v. 239, 240.

„ ABIETINA, Sars, Bemrcrkn. over fire .Norske Hydroider, Viden-
skabs. Forhandl. 1862.

Plate XLI. fig. 3.

STEM stout, horn-coloured, irregularly branched, the bran-
ches constricted at the base; HYDROTHEC/E disposed in
four (or five) longitudinal rows, those of the adjacent
rows alternating, those of the opposite on a line with
each other, free above, and bending outwards to a dis-
tance nearly equalling the width of the stem, with an
even margin; GONOTHEC^E unknown; POLYPITES of a
sulphur-colour, with 18-20 tentacles.

Height, in fine specimens, nearly 4 inches.

THIS species has been fully investigated by Sars, who has
obtained it abundantly on the Norwegian coasts, and has
had ample opportunity of studying it in a living state.
He has given a detailed account of the polypites, which
are of the same type as those of Lafoea dumosa. " They
are cylindrical, very slender and tall, so that when ex-
tended they only occupy a third of the diameter of the

SALACIA ABIETINA. 213

calycle, and project fully a calycle's length beyond the
opening. The body is slightly thicker at the upper ex-
tremity, where the mouth is placed on the top of a conical
proboscis, which rises from the centre of the tentacular
wreath." The tentacles are held alternately erect and
standing out straight from the body. The colour of the
polypites is light sulphur or greenish yellow. " They are
very shy, seldom protrude themselves, and only when they
are in perfectly fresh sea-water. At the slightest touch
or shaking of the vessel in which they are kept, they draw
themselves back with extreme rapidity and with a jerk,
like the Polyzoa, not only into their calycles, but, as the
latter are not furnished with a transverse partition, even
out of them, and within the tube of the compound stems
and branches, so that the calycle is left quite empty."
" The whole polypary is strong, rigid, of a light brownish-
yellow colour ; the calycles are transparent, with a slight
yellowish tinge"*. Sars has never found any trace of the
reproductive bodies.

The Grammaria robusta (Stimpson) is founded on young
and unbranched specimens of the present species.

Hab. From the deep-water fishing-boats, Northumber-
land, rather rare; Coquet and Berwick Bay (J. A.) : Shet-
land, not rare in deep water (A. M. N.) .

[Near Bergen, in 30-40 fathoms, on stony ground, not
rare ; North Cape, of larger size and more luxuriantly
branched (Sars) : Grand Manan, Bay of l\moly, Lami-
narian zone (Stimpsou).

Salacia abietina is confined to the north, and, accord-
ing to Sars, is a truly Arctic form. The north appears
to be the headquarters of the Lafoeidce generally.]

* Beimvrkuinger over IhvXorsko H\ ih-oitkT, p. l.'J.

214 LAFOEIDJE.

Genus FILELLUM, Hincks.

Der. Dimin. offilum, a tliread.
KETICTLARIA, Wyvillo Thomson.

GENERIC CHARACTER. — Stem creeping, filiform, reticulate,
immersed in a chitinous crust ; hydrothecce tubular, decum-
bent, adherent, without operculum, irregularly disposed
along the stem, to which they are attached at the base or by
a short stalk ; gonotheca unknown.

THIS genus was constituted by Prof. Wyville Thomson
under the name of Reticularia, which unfortunately had
been previously assigned to a group of Fungi, and there-
fore cannot be retained.

I have not been able to satisfy myself as to the presence
of a crust involving the creeping stem, and have included
this character in the definition of the genus on the authority
of Prof. Thomson.

F. SERPENS, Hassall.

CAMPANULARIA SERFENS, Hassall, Zoologist, No. 69, 2223; Transact. Micr.

Soc. iii. (1852) 163, pi. xxi. fig. 4.
CAPSULARIA SERPENS, Gray, Brit. Mus. Badiata, 151.
EETICULAUIA IMMEKSA, Wyville Thomson, Ann. N. H. (2nd ser.) xi. 443, pi. xvi.

figs. 2, 3.
„ SERPENS, Hincks, Ann. N. H. (2nd ser.) xviii. 469 (1856).

Plate XLI. fig. 4.

STEM extremely delicate, forming an irregular network ;
HYDROTHEC^E oblong, with an even patulous rim, at-
tached for about two-thirds of their length, free and
curved upwards towards the aperture, sessile or with a
very short stalk, sometimes laid alongside the stem, and
sometimes forming an angle with it; GONOTHEC^: un-
known ; POLYPITES very minute, of a greenish colour.

THIS is the common parasite of some of the larger Sertu-

TRICHYDRID^E. 215

lariiclse, and especially of Sertularia abietina. The calycles
very generally overspread the stem of this zoophyte, and
are often so densely and confusedly massed together that
it is difficult to distinguish their shape ; in such specimens
they form a crust, bristling with the free tubular orifices.
On a broader surface, where there is space for more regu-
lar development, the species assumes a very different and
a much simpler appearance ; the hydrothecse are sparingly
distributed, and their character is recognized at once.
Specimens of this kind are found occasionally on shells.
The calycles sometimes occur in pairs, one on each side of
the stem, sometimes singly, and sometimes in companies.

Hab. On Sertularia abietina, Hydrallmania falcata, and
other zoophytes, and on shells occasionally; very common.

[Off Reikiavik, Iceland, in 100 fathoms (T. H.).]

Family V. — Trichydridze.

HYDROTHEC.E merely rudimentary, tubular ; POLYPITES cy-
lindrical, very extensile, with a small conical 'proboscis.

Genus TRICHYDRA, T. S. Wright.

Der. From 9pi£ (rpi%6s), hair, and Hydra, a polypite.

GENERIC CHARACTER. — Stem creeping, branched ; hydro-
thecae rudimentary, consisting of very short tubular pro-
cesses, given off at intervals from the creeping stem ; poly-
pites cylindrical, very slender and extensile, with a short
conical proboscis.

Reproduction unknown.

I FEEL very doubtful as to the true position of this ob-
scure genus. Wright would place it amongst the Corynida>
of Johnston, on account of the progressive development of

216 TRICHYDBJD^E.

the tentacles. He also states that the polypites show no
disposition to hold the tentacles in a double row ; but Van
Beneden's testimony is to the opposite effect*. He ranks
the species under Eudendrium, with which genus, as now
defined, it has little in common.

Allman includes Tricky dr a amongst the Campanulariidts;
but it has no affinity with the typical forms of this family.
Any position assigned to it at present can only be regarded
as provisional.

The polypites in many points resemble those of the
Lafoeidce and Campanulinidce, and are wholly retractile
within the tubular thecae. The latter, though remarkable
for their minuteness, exhibit the simple cylindrical form
which is met with in some of the Lafoeidte. In the
absence of all trustworthy information f respecting the
gonosome, I shall make Trichydra the type of an allied
family.

T. PUDICA, T. S. Wright.

TRICHYDKA PUDICA, Wright, Edinb. New Phil. Journ. (N. S.) for Jan. 1858,

6, pi. iii. fig. 1.
?EuDENDRit'M PUDICUM, Van Bcneden, Faune Litt. de Belg. Polypes, 116,

pi. viii. figs. 1, 2.

Woodcut, fig. 26.

CffiNOSARc enclosed in a transparent, membranous poly-
pary; HYDROTHEC^E cylindrical, even-rimmed, of un-

* It may perhaps be doubtful whether Van Beneden's zoophyte is iden-
tical with the present form, since he represents the polypary as a delicate
and transparent covering, which extends over a great part of the body of the
polypite, rising much higher than in Wright's figures. In other points it
agrees with it.

t Wright figures a meclusoid (Micr. Journ. iii. 50, pi. vi.) which he found
in the vessel containing Trichydra, and fancied might be its sexual zooid ;
but he could detect no trace of gonophores on the zoophyte, and we must
therefore wait for further evidence.

TRICHYDRA PUDICA.

217

equal length, but all very short ; POLYPITES about £ inch
in length, exceedingly attenuated during extension,

Fig. 26.

transparent, with the exception of the proboscis, which
is of a dense silvery white; TENTACLES 4-12, long and
waving.

"Tnis interesting little zoophyte is remarkable for the
laxity of its habit and the extensibility and transparency
of its polyps." When at rest they " extend their bodies
and tentacles to their utmost length ; but a sudden glare
of light or shaking of the vessel in which they are confined
causes the modest hair-polyp to contract itself, or to bend
the buccal cavity and tentacles loosely downwards, like a
flower drooping on its stalk. It seldom entirely with-
draws itself into its cell unless irritated." (Wright.}
Hab. The "Fluke Hole," Firth of Forth, covering a

218

small shell ; " shells and stones, which have been kept
quiet in an aquarium for some time, are occasionally
covered with it " (T. S. W.).

Family VI.- — Coppiniidae.
united by an encrusting, cellular mass.

Genus COPPINIA, Hassall.

Der. Named after Mr. Coppin.

GENERIC CHARACTER. — Zoophyte consisting of a number
of long tubular hydrothecce crowded closely together and
united by an adherent cellular mass, which involves the
lower portion of them, the upper portion remaining free ;
ova developed in the cavities of the cellular mass, and es-
caping as planul<s ; polypites cylindrical and very extensile.

THIS is an aberrant form amongst the Hydroida; and
too little is known of its structure and development to
enable us to speak with confidence respecting its relations
to its tribe. Its calycle and polypite ally it to the Lafocidce,
and it is propagated, like the Hydroida generally, by
means of plaiiulae ; but it presents us with several striking
peculiarities. The individual polypites are not united at
the base by a creeping stem, but are bound together by a
spongy, cellular mass, hi which their calycles are plunged,
as it were, for a considerable portion of their length.
This mass adheres to the surface, and often involves the
stem, of various Sertularian zoophytes.

"Additions to the colony," according to Prof. W.
Thomson, ' ' appear to take place by the budding of the
hydrse at the base of the tube-like cell, by which process
a new hydra is formed, which is separated from its parent,
secretes a tube-cell of its own, and ultimately secretes a

COPPINIA ARCTA. 219

quantity of granular matter, which pushes it still further
from the rest of the community."

The ova are produced in the cavities or compartments
which pervade the common connecting-substance, and
give a tessellated appearance to its upper surface ; they
are found in great numbers clustering around the tubes of
the hydrothecse, in the upper portion of the matrix, a
little below the surface. I have never seen them in the
deeper parts of it. After the escape of the planules, a
small aperture is visible in the covering of each compart-
ment. Dalyell, from whom we have the fullest account
of this zoophyte, throws no light on the nature of the
ovarian chamber or the development of the ovum; and
in the few cases in which I have had the opportunity of
examining recent specimens, I was unable to determine
these points.

The ova lie singly or in clusters, and without any regu-
larity of arrangement, within the matrix. Each of them
is enclosed in a delicate, transparent membrane.

The planule is elongate, broad at one end, and tapering
off towards the other, about one-third of a line in length,
and not ciliated. It moves in worm-fashion, and is of a
greenish-yellow colour. When it ceases to move, accord-
ing to Dalyell, the body becomes round and deeply annu-
lated, exhibiting a number of prominent segments. One
end enlarges while the other is elongating, and the latter
is moulded into a calycle with its contained polypite.

C. ARCTA, Dalyell.

SERTULARIA ARCTA, Dalyell, Bare and Eeraark. An. Scotl. i. 224, pi. xlii.
COPPINIA MIRABILIS, Hitssfill, Zoologist, No. 09, 2223; Trans. Microscop. Soc.
iii. 160, pi. xxi. figs. 1, 2.

Plate XLI. fig. 5.

ZOOPHYTE forming small, irregular, encrusting masses of

220 HALECIIDJ*:.

a greenish-yellow colour ; HYDROTHEC.E long and slen-
der, with an even aperture, the free portion generally
curved ; POLYPITES with 8-10 tentacles, stretching to a
great distance beyond the opening of the calycle when
extended.

THE calycle is provided with a valve-like operculum, which
closes on the retreat of the polypite. Great numbers of
planulse are liberated ; and as they escape the mass loses
its yellowish colour, which is due to their presence.

It is not improbable that the Campanularia intertexta of
Couch (Conchella intertexta, Gray) may have been founded
on the present species ; but the description in the c Cornish
Fauna ' is not sufficient for identification.

Hab. On the stems of other zoophytes, especially Ser-
tularia abietina and Hydrallmania falcuta ; common and
widely distributed.

Family VII. — Haleciidse.

HYDKOTHEC^E biscnal, subsessile, jointed to a lateral pro-
cess from the stem; POLYPITES partially retractile.

Genus HALECIUM, Oken *.

THOA, Lamouroux (1816).

GENERIC CHARACTER. — Zoophi/te plant-like, more or less
branched, rooted by a creeping stolon ; hydrothecce biserial,
tubular or deeply campanulate, subsesslle, jointed to a short
lateral process from the stem ; poly pites partially retractile,
large and fusiform ; gonothecce scattered, dissimilar in the
two sexes ; reproduction by means of fixed sporosacs.

THE genus Halecium is somewhat intermediate between

* Lcln-buch Naturg. 91 (1815).

HALECITJM HALECINUM. 221

the Campanularian group and the Sertulariidcs ; its caly-
cles are subsessile, and not let into the stem as in the
latter family. Its habit makes an approach to that of the
Campanulariidce ; while its large and scarcely retractile
polypites remind us of those of the Athecata.

In some species, and possibly in all, the female capsule
exhibits a curious peculiarity, being surmounted at a
certain stage by two perfectly formed polypites which pro-
trude from the orifice, and are seen to be a continuation
of the column that traverses the cavity and bears the
gonophore. This is the only instance amongst the Theca-
phora in which the proliferous polypite is not permanently
atrophied and reduced to a mere columnar offshoot from
the coanosarc ; but amongst the Athecata it is commonly
fully developed, and the cases of partial or complete atrophy
are exceptional. These capsular polypites were first noticed
by Van Beneden on H. halecinum; they occur onH. Beanii;
and I have also found them on H. nanum, a species from
the gulf-weed described by Alder.

The marked peculiarities of Halecium entitle it to be
made the type of a distinct family.

1. H. HALECINUM, Linnfeus.

"HERRING-BONE CORAL," Ellis, Corall. 17, pi. x.

SERTULARIA HALECINA, Linn. Syst. 1308; Pall. Blench. 113; Esper, Pflanz.

Sert. t, xxi. figs. 1,2; Lamk. An. s. V. (2nd ed.) ii. 146.
TIIOA HALECINA, Lamx. Cor. flex. 211 ; Blainv. Actinolog. 488, pi. Ixxxiv.

figs. 4, 4 a.
HALECIUM HALECINUM, Schwcigger, Handb. 42fi ; Johnston, B. Z. 58, pi. viii.

Plate XLTT.

SHOOTS erect, of a rigid habit, irregularly branched, springing
from a sponge-like mass of fibres; STEMS compound,
made up of many delicate tubes, tapering upwards ;

222 HALECIID^E.

principal branches also compound, pinnate, or bipinnate ;
pinnae alternate, placed at regular intervals, sometimes
themselves pinnate, jointed, the internodes short and
stout ; HYDROTHECjE alternate, one or a pair immediately
below each joint, tubular, with a plain and slightly
everted rim-, GONOTHEC^E borne in rows on the upper
side of the pinnae, — (male) ovate, slender, tapering off
below, with a very short pedicel of about two rings;
(female) oblong, broad above and narrowing towards the
base, with a short tubular orifice at one side of the sub-
truncate top.

THIS species, which is one of the commonest of the British
Hydroids, attains a height of from 6 to 10 inches ; it is
somewhat coarse in appearance, and characterized by a
marked angularity and stiffness of habit. The disposition
of the branches and pinnae is very regular and definite, and
they all form an acute angle with the stem from which
they spring. The calycles, in their simplest condition,
consist of a single tubular piece articulated to a projection
from the stem ; in older specimens, however, they are
made up of several such pieces, which fit into one another
and mark the successive generations of polypites.

The principal stems are composed of a multitude of
extremely delicate tubules, agglutinated together, as
many as a hundred strands combining in the main trunk
of the zoophyte. Some of these diverge at regular inter-
vals to form the larger branches and the pinnse, and the
stem is thus gradually attenuated upwards, until at the
apex it runs out to a fine point. The polypites are large,
elongate, somewhat fusiform, and have rather thick ten-
tacles.

Hab. On shells, stones, &c., in both shallow and deep
water, but more usually the latter; very common and
generally distributed.

IIALECIUM MURICATUM. 223

[Coast of Belgium (Van Ben.) : Greenland (Mb'rch) :
Tromso and North Cape in 30-50 fathoms., common
(Sars): Labrador (A. S. Packard, jun.): Massachusetts
Bay (A. Agassiz): Mediterranean (teste Pallas).]

2. H. MURICATUM, Ellis and Solander.

SERTULARIA MURICATA, Ellis 8f Soland. Zooph. 59, pi. vii. figs. 3, 4 ; Esper,

Pflanz. Serb. tab. xxxi. figs. 1, 2.

LAOMEDEA MURICATA, Lamx. Expos. Meth. 14, pi. vii. figs. 3, 4.
CAMFANULARIA MURICATA, Slainv. Actinolog. 473.
TIIOA MURICATA, Couch, Corn. Faun, pt. iii. fig. 16.
HALECIUM MURICATUM, Jofmst. B. Z. 60, pi. ix. figs. 3, 4.

Plate XLIII. fig. 1.

ZOOPHYTE stout and riyid, springing from a fibrous mass,
irregularly and densely branched, yellowish brown; STEM
and branches compound, consisting of many tortuous
tubes agglutinated together, sometimes simple at the
extremity ; branches erecto-patent, pinnate, slightly
tapering; pinnse alternate, delicate, jointed ; HYDRO-
THECJE placed alternately, one below each joint, tubular,
rather short, with a much everted rim ; GONOTHEC^E ovate,
on a short pedicel, roughened by raised roivs of prickles,
which radiate towards each side from a central line,
crowded on the stem and branches.

H. MURICATUM is of a rugged aspect; the stems and branches
are thick and coarse, and frequently almost hidden by the
clustering masses of capsules. The ramification is luxii-
riant, erect, and rigid.

The capsules, which are beautiful objects under the
microscope, have much the appearance of a minute bi-
valve shell, with a spinous surface; they are borne in
extraordinary profusion on all parts of the zoophyte. No

224 HALECIID^.

difference between the sexes in the shape of the gonotheca
has as yet been noticed.

Hab. On shells, &c., from deep water, not common;
Peterhead, Wick, Banffshire, from fishermen's lines ; Firth
of Forth (C. W. P.): on oyster-shells from Loch Ryan
(D. L.): Northumberland (J. A.): Seaton (J. Hogg):
Whitby (T. H.): Scarborough (W. Bean): Cornwall, off
Mevagissey, rare (Couch): Giant's Causeway (A. H. H.).

[Off Reikiavik, Iceland, in 100 fathoms (T. H.): on a
fishing-bank off Caribou Island, Straits of Belle Isle, in
30-50 fath., frequent ; Square Island, a few miles north of
Cape St. Michael, in 30 fath., common (A. S. Packard,
jun.).]

3. H. BEANII, Johnston.

THOA BEANII, Johnston, B. Z. (1st eel.) 120, pi. vii. figs. 1, 2.
HALECIUM BEANII, Johnston, B. Z. (2nd ed.) 59, pi. ix. figs. 1, 2.

Plate XLIII. fig. 2.

ZOOPHYTE shrubby, irregularly branched, of a delicate and
graceful habit; STEM and larger branches compound,
tapering upwards, pinnate; pinnae alternate, often
branched, slightly zigzag, jointed at short intervals;
HYDROTHECJE alternate, one below each joint, small, tubu-
lar, somewhat dilated towards the aperture; GONOTHEC^E
borne at the base of the calycles, — (male) elongate-
ovoidal; (female) slipper -shaped, with a short tubular
orifice in the middle of the upperside.

THIS pretty species is extremely light and delicate, and, in
the absence of the curious female capsule, may be easily
recognized by its habit and mode of growth. In its young
state it is simply pinnate, but becomes much and variously
branched and assTimes a very bushy appearance. The

HALECIUM LABROSUM. 225

stems are much more slender than those of H. halecinum,
the ramification is more irregular and intricate, and there
is none of the stiffness and formality which characterize
that species.

H. Beanii seems to be generally dioecious ; but the two
sexes are sometimes mingled on the same shoot. The
female capsule contains from 4 to 6 ova, arranged in a row,
which are matured into white, somewhat flask-shaped
planulae. This species is commonly about two inches in
height, but occasionally rises to five or six.

Hal). On shells &c., and very often parasitic on other
zoophytes, from moderate depths to deep water; common
and widely distributed.

4. H. LABROSUM, Alder.

Ann. N. II. (ser. 3) iii. 354, pi. xii. figs. 1-3.

Plate XLIY. fig. 1.

•-•

ZOOPHYTE irregularly branched, and of a somewhat flaccid
habit, purplish when fresh, attached by numerous fibres;
STEM composed of several tubes ; the larger branches also
compound, generally dividing dichotomously, pinnate;
pinna alternate, jointed, often bearing pinnules, and
more or less ringed transversely above each joint ; HYDRO-
THECyE borne singly or in pairs below the joints, mode-
rately deep, much expanded and everted at the margin,
jointed and ringed at the base ; GONOTHEC.E (male) ovate,
broad below and obtusely pointed above, of a purplish-
brown colour, set on a short pedicel of about two rings ;
(female) ovate, broad below and tapering upwards, cleft
at the summit.

THIS fine species is one of Mr. Alder's numerous additions
to the list of British zoophytes. It may be readily dis-
tinguished from H. halecinum, even if the reproductive

Q

226

HALECIID^E.

Fig. 27.

capsules should be absent. Its mode of growth is lax and
irregular, and contrasts strongly with the stiff and erect
habit of its ally ; its stems are not so stout, and the
texture is more delicate. The annulation of the branches
which is often very strongly marked, and the form of the
deep, somewhat campanulate calycle, with its elegantly
everted margin, are good distinctive signs. The purplish
colour, too, seems to be a constant character in fresh speci-
mens.

The male capsules only have been described by Mr.
Alder. I am indebted to Mr. Peach
for very fine specimens from Wick,
bearing the females in abundance.
(Woodcut, fig. 27.)

As in the other species of this genus,
the calycles are often composite, seve-
ral cups rising one within the other
and registering, as it were, the number
of polypites that have budded succes-
sively and perished.

H. labrosum is commonly between
3 and 4 inches high, but occasionally
reaches 6 inches.

Hob. Coast of Northumberland, deep water (Alder):
Moray Firth (Mr. Macdonald): Shetland (Barlee): Wick,
on fishermen's lines (C. W. P.).

5. H. TENELLUM, Hincks.

HALECIUM TENELLUM, HincJcs, Cat. Devon & Cornw. Zooph., Ann. N. H. (3rd

ser.) viii. 252, pi. vi. figs. 1-4.
HALECIUM LABROSUM (young), Alder, Ann. N. H, (3rd ser.) iii. 355.

Plate XLV. fig. 1.
ZOOPHYTE minute and extremely delicate ; STEM slender,

HALECIUM PLUMOSUM. 227

often strongly ringed at intervals, irregularly branched,
branches given off at the base of the calycles, sometimes
singly, sometimes in pairs ; HYDROTHEC^E funnel-shaped,
gracefully everted at the margin, often of considerable
length, in many cases a number (frequently 4 or 5)
rising one within another; GONOTHEC.E ovate, smooth,
borne on short pedicels and occurring singly.
Height of fine specimens from \ to ^ an inch.

THIS very beautiful species is remarkable for its extreme
slightness and delicacy. There is much variety in the
amount of annulation on the stems and branches ; some-
times, as in the specimens from which my first description
was taken, they are almost smooth, in other cases they
are distinctly and very elegantly ringed. A simple
calycle is rarely met with on mature specimens. Gene-
rally the polypite protrudes from the uppermost of a pile
of little cups, with prettily everted rims, which fit one
into the other.

The capsules vary in form, being broadly ovate, or
slender and somewhat pointed above; they contain a
single, large gonophore.

Hub. On zoophytes and Polyzoa. Salcombe Bay, Devon,
on Salicornaria farciminoides ; Filey (T. H.): Northum-
berland, on Tubularia indivisa and Sertularia abietina, from
deep water (J. A.) .

6. H. PLUMOSUM.
Plate LXIV. fig. 1.

SHOOTS tall and slender, flexible, sparingly branched; STEM
and branches compound, tapering, pinnate ; pinnce alter-
nate, placed at regular intervals, simple, delicate, some-
times bearing a few pinnules, divided by oblique joints
into very short and somewhat wedge-shaped internodes ;

228 HALECIID^.

alternate, one immediately below each
joint, the lateral process small and closely appressed to
the stem, the cup slender, expanding at the top, and
slightly everted; GONOTHEC.E unknown.

I VENTURE to describe this species, from a specimen in the
collection of Trinity College, Dublin, even in the absence
of the reproductive capsules. The most marked charac-
teristic is the slender, flexible, and feathery habit. The
stem, though composed of several tubes, is delicate as
compared with that of H. halecinum, and altogether wanting
in the rigidity which belongs to that species. The minute
structure of the pinnae is also peculiar ; they are divided,
by joints which are decidedly oblique (slanting alternately
in opposite directions), into numerous very short seg-
ments, which are not of equal width throughout, but taper
somewhat downwards. The process that supports the hy-
drotheca projects but little; and the cup is small, with a
slightly everted margin. H. plumosum attains a height of
T> inches.

The H. filiforme* of Alder seems to resemble the present
species in its mode of growth, but it is described as having
a simple stem and rather long internodes.

Hab. Ireland.

* I do not include this form in the present work, as Mr. Alder, I believe,
saw reason to change his opinion about it, and to regard it as probably a mere
variety or an immature state of some other species. The following is his
description: —

" H. FILIFORME, n. sp. — Polypary very slender, flexible, simple or consisting
of a single tube throughout ; the stem not much branched ; branchlets short,
alternate, arising from the side of a cell ; the internodes rather long ; cells
rather slender, tubular, with a slightly everted margin. Length 4 } inches.''-
Suppl Cat. North. $ Durh. Zooph.

HALECIUM SESSILE. 229

7. H. GENICULATUM, Norman.

•• On the Hydrozoa &c. of the Hebrides,'1 Eeport of the British Assoc. for
1866, 196.

STEM slender, branching, the branches all in the same
plane ; branchlets flexuous, bending alternately right and
left between the calycles, jointed, the joints consisting of
a single stricture or more rarely two; HYDROTIIEC.E
borne immediately below the joints, much elongated,
simply tubular, fully two-thirds as long as the internodes,
constricted near the base ; GONOTHEC.E unknown.

Height 1| inch.

THE bent stem, resembling in this respect that of Obetia
geniculata, and the very long calycles are the most salient
characters.

Hab, Dredged in deep water in the Minch (A. M. N.).

8. H. SESSILE, Norman.

'• Oil the Hydrozoa &c. of the Hebrides," Keport of the Erit. Assoc. for
1866, 196.

Plate XLIV. fig. 2.

STEM slender, irregularly branching, branches not in the
same plane; branchlets jointed, the joints consisting of
a single stricture; HYDKOTHEC^E alternate, very short,
and perfectly sessile, not rising at all separately from the
lateral stem-processes, of which they are mere openings,
without being raised into a tube ; GONOTHEC.E unknown ;
POLYPITES large, very narrow at the base, thence gra-
dually expanding to the summit, where they suddenly
swell into a wide, campanulate mouth ; tentacles long
and slender.

Height (probably) 1^ inch.

THE size of the polypites in this species is remarkable.

230

They rise, according to Norman, " above the hyclrotheca
to a height (exclusive of tentacles) which is not less than
five times its diameter, and far overtop the level of the suc-
ceeding hydrotheca." The calycles are quite rudimentary.
Hob. In deep water in the Minch (A. M. N.).

Genus OPHIODES, Hincks.

Der. otptwSijs, snake-bearer.

GENERIC CHARACTER. — Stem branching, rooted by a
creeping stolon ; hydrothecae vase-shaped ; poll/piles not
retractile within the calycle ; the body deeply constricted
a little below the base of the tentacles; tentacles in a
single verticil, muricate, webbed, and surrounding a coni-
cal proboscis ; tentaculoid organs borne singly on the stem
and on the creeping stolon, highly extensile, protected at the
base by a small chitinous cup, and terminated at the upper
extremity by an enlarged capitulum armed with thread-
cells ; reproduction by means of fixed sporosacs.

THE remarkable tentacular organ with which Ophiodes is
furnished, and which may be regarded as the equivalent of
the nematophore, consists of a very extensile, snake-like
appendage, with an enlarged head, attached at the lower
extremity by an extension of the coenosarc. The base is
protected by a small chitinous tube, which expands from
its point of origin upwards; the capitulum contains
numerous thread-cells, from which very long threads,
barbed below, are emitted.

These tentaculoid organs are capable of great elongation
and contraction, and execute the most vigorous move-
ments, stretching themselves out with apparent eagerness

OPIIIODES MIRABILIS. 231

and twisting in all directions. When extended, they are
often three or four times the length of the polypite, and in
this state appear as most delicate, hair-like filaments.
My attention was first drawn to the zoophyte by a number
of them dispersed on the creeping stolon, which were
twirling themselves about in the maddest fashion, as if to
scare away invaders.

One of these curious organs is almost always attached
to the stem a little below the calycle, and when extended
rises far above it ; and as it twists itself about, with its
formidable armature ready for instant action, it has all the
appearance of a purveyor or protector to the polypite.

A striking feature of the genus Ophiodes is the con-
striction of the body of the polypite, dividing it into
two well-marked regions — the oral, including the proboscis
and the tentacular wreath and a kind of jM^m-pharynx,
and the aboral, traversed by the digestive cavity.

The polypite does not extend to the bottom of its hy-
drotheca, but rests on a membranous diaphragm that
shuts off the upper third of it and forms a cup-shaped
chamber. This diaphragm is perforated in the centre
(Plate XLV. fig. 2 c); and through the orifice the body is
linked on to the coenosarc, which traverses the lower por-
tion of the calycle.

O. MIRABILIS, Hincks.

Aunals N. H. for November 1866, (ser. 3) xviii. 421, pi. xiv,

Plate XLV. fig. 2.

STEM erect, sparingly branched, rudely annulated at the
base, and jointed at intervals throughout; HYDROTHEC^;
bulging slightly immediately above the base, with the

232 HALECIIDyE.

sides incurved, expanding gradually towards the top,
with a patulous opening and an everted rim ; a single
TENTACULOID ORGAN on the stem a little below the
calyclc, and many distributed 011 the creeping stolon;
GONOTHECJE ovate, ringed transversely, with a wide tubu-
lar neck, subpedicellate, borne on the creeping stolon;
POLYPITES very tall when extended, the inferior portion
of the body clavate, the oral funnel-shaped ; tentacles
about 18, a brownish cluster of thread-cells between
each pair, on the connecting web.
Height about £ inch.

THE branching of O. mirabilis is very slight and simple.
It forms small tufts, bearing three or four polypites ; the
extremity of the stem often runs out into a long, filamen-
tary offshoot, with short lateral branches.

The polypite, when fully extended, is a singularly
beautiful object, imitating to some extent the form of a
tall and graceful candelabrum ; only the base of the
body is within the calycle. The web that unites the lower
portion of the tentacles forms a rather deep cup* surround-
ing the proboscis, with the batteries of thread-cells, which
glitter against a dark ground, set round the outside of it.
These intertentacular thread-cells are similar to those
which thickly cover the capitulum of the snake-like organs.
They emit a very long thread with a barbed base ; these
slender filaments may be seen cast forth beyond the ten-
tacles and intermingling with them, and must constitute
an effective auxiliary force for the capture of prey. The
arms are held alternately elevated and depressed.

When kept in confinement the tentacles are soon
thrown back, drooping listlessly downwards, and the pro-

* There is a conspicuous opake-while collar within this cup, al the base
of the anus.

SERTULA1UID.E. 233

boscis becomes extraordinarily prominent; the whole as-
pect of the polypite is changed.

I have only met with one or two gonothecse. A single
large sporosac occupied the interior, in the centre of which
was a somewhat flask-shaped, opake body, terminating
above in a narrow neck (Plate XLV. fig. 2 d) : this was
probably the spermary.

Ojjhiodes mirabilis, it will be seen, exhibits a large
number of interesting characters.

The distinct funnel-shaped head crowning the tapering-
body, and itself crowned by the tentacular verticil with its
battery of thread-cells at every embrasure, the elegant
calycle, the strange snake-like organ near it, either resting
motionless and sentinel-like, or twisting vehemently about
and casting abroad its fatal threads, and the numerous
similar organs below, writhing and lashing themselves
about, without apparent object, constitute a really remark-
able group of curious structures.

Hub. On weed, dredged in shallow water (5-8 fathoms),
Swaiiage Bay, Dorset ; Ilfracombe, chiefly on Laminaria-
roots and stems, from the lower ledges 011 the Capstone,
very abundant (T. H.).

Family VIII. — Sertulariidse.

perfectly sessile, more or less inserted in the
stem and branches ; POLYPITES ivholly retractile, with
a single wreath of filiform tentacles round a conical
proboscis; GONOZOOIDS always fixed.

234

SERTULARIIDJE.

Fig. 28.

S. fusiformis (Hincks).

S. temtta (Aider).

Genus SERTULARELLA, Gray.

Der. Diminutive of Sertularia.

SBRTULARIA aucfc. (in part).

COTULINA, Agassiz, N.H. United States, iv. 356 (for 8. polyzonias only).

AMPHITKOCHA, Agassiz, ibid. iv. 356 (for S. rugosa).

GENERIC CHARACTER. — Zoophyte plant-like; stem more
or less branching, jointed, rooted by a creeping stolon ; hy-
drothecae biserial, decidedly alternate, with a toothed orifice,
and an opercidum composed of several pieces ; gonothecte scat-
tered, transversely ringed, slightly dissimilar in the two sexes.

THE genus Sertularella was constituted by Gray, to in-
clude that Section of the Sertularice of which S.polyzonias
may be regarded as the type. Only two British species
had been recognized at the time of the publication of his
list ; but the number has since been increased to six. In
other parts of the world the group is largely represented ;
and the examination of many foreign forms has led me to
retain the genus. The decidedly alternate arrangement

SERTULARELLA POLYZONIAS. 235

of its calycles is accompanied by a peculiar and character-
istic habit of growth. The physiognomy, indeed, of the
group is very striking, and the principal characters are
well marked. The calycles have always a toothed orifice,
and are closed by a somewhat prominent operculum
composed of several convergent pieces. The reproductive
capsules, whilst exhibiting many varieties of form, are
always more or less wrinkled or ringed transversely ; they
have usually a denticulate aperture. The male and female
only differ in size and in the nature of their contents.

The type species (S. polyzonias} seems to be very
generally distributed. Two or three of our British forms
range to the extreme north, and S. tricuspidata may be
said to have its metropolis there. In the same region
a remarkable variety of S. polyzonias occurs, of a very
robust habit and having its calycles more than double the
usual size. I have specimens from Iceland; and Sars has
obtained it near the North Cape. He also states that he
has received the same variety from Massachusetts, U.S.

The genus is represented in the South Seas by a
number of forms distinct from those of Europe. One of
them (the S. Johnstoni, Gray) makes a near approach to
our S. tricuspidata.

1. S. POLYZONIAS, Linn.

" GREAT TOOTH CORALLINE," Ellis, Corall.5, pi. ii. figs. « A, b B, and pi. xxxviii.

figs. 1 & A.

SERTULARIA POLYZONIAS, Linn. Syst. x. 813 ; Esper, Pflanzenthiere, Sert. t. yi.
figs. 1-6; Lamk. An. s. Vert. ('2nd ed.) ii. 142; Lama:. Cor.
flex. 190; Johnsf. B. Z. 61, pi. x. figs. 1 & 3; Ddyctt, Kern.
An. i. 134, pi. xxii.

„ FLEXUOSA, Linn. Syst. x. 814, no. 34.

„ ERICOIDES, Pall. Elench. 127.

„ PINNATA, Templeton, Mag. N. H. ix. 468.

HIBERMCA, Johnsf. B.Z. (1st ed.) 128.

., ELLISII, M.-Edwarch, Lam. An. s.Vert, (2nd ed.) ii. 142; Johmt.

B.Z. (1st ed.) 123.

236 SERTULARIID^.

SEUTULAKELLA POLYZONIAS, Gray, B. M. Kadiata, 68.
COTULINA POLYZONIAS, Ayassiz, N. II. U. S. iv. 350.

Plate XLVI. fig. 1.

STEMS slender, slightly ivaved, irregularly branched ;
BRANCHES subflextious, alternate, but produced at unequal
distances, often themselves much and variously branched,
jointed obliquely ; HYDROTHEC/E placed immediately be-
low the joints, distant, urceolate, bulging below, above free
and divergent, with a wide, everted and ^-toothed aper-
ture; GONOTHEC^E produced at the base of the calycles,
large, ovate, wrinkled transversely, with a tubular quadri-
dentate orifice, and shortly stalked.

S. POLYZONIAS presents many varieties of size and habit ;
but the shape and arrangement of the calycles suffice for
its identification amidst them all. It is often of very
luxuriant growth, forming large, arborescent masses, which
exhibit the most complex ramification. The main portion
in such cases sends off at intervals long, slender shoots,
which in their turn originate a whole system of offshoots,
each of them much branched, the whole constituting a
perfect tangle of interlacing stems. Such masses, when
freshly cast upon the shore, and before the evanescent
colour has faded, have a certain exquisitely delicate beauty,
and may almost be said to glitter on the dark heaps of
seaweed. Between tide-marks the species is of much
humbler growth.

When living, S. polyzonias is of a bright straw-colour
and is certainly one of the prettiest, as it is one of the most
generally distributed, of the Hydroids. It is a littoral as
well as a deep-water species, having a wide range bathy-
metrically no less than in space. It is in truth a cosmo-
politan form, having been met with in most parts of the
world.

The polypites are large, and have 20 or more ten-
tacula. The female reproductive capsule contains a

SERTULARELLA GAYI. 237

single sporosac ; and the eggs at a certain stage of their
development are discharged from it into an external mar-
supium, in Avhich they are matured into free, ciliated
embryos (planufa) . Ellis, with his accustomed accuracy,
has figured it in this condition, surmounted by the delicate
sac crowded with the ripening ova.

The male and female capsules differ considerably in size,
the former being the smaller and of a whitish colour, whilst
the female are coloured yellow by the contents.

Hab. On shells, seaweeds, &c. ; generally distributed
round our coasts.

[Massachusetts, robust var. ; Greenland, do. (Sars) :
Iceland, do. (T. H.) : Newfoundland (Landsborough) :
Straits of Belle Isle, between tide-marks, common, in
deeper water very stout and large (A. S. Packard, j mi.):
Grand Manan, Bay of Fundy (Stimpson) : Madeira;
South Africa; Falkland Islands (Busk) : Red Sea (T. H.):
La Charente inferieure (Beltremieux): Lussin Piccolo,
Adriatic (Grube): Mediterranean (Cavolini).]

2. S. GAYI, Lamouroux.

SKRTTLARTA GAYI, Lamx. Expos. M£th. 12, tab. Ixvi. figs. 8, 9 ; HincJcs, Cat.

Devon and Corn. Zooph., Ann. N. H. (3rd ser.) viii. 2r>2;

Alder, Cat. North. Zooph., SuppL, in Trans. Tynes. F. C-

v. 23(i.

„ ERICOIDES, var., Pall. Elench. 128.
LA SEUTULAIRE DE GAY, Blainv. Man. d'Actinol. 481.
SERTULARIA POLYZONIAS, var. /3, Johnst. B. Z. Gl, pi. x. fig. 2.

Plate XLVI. fig. 2.

SHOOTS erect, composite, pinnate; BRANCHES alternate,
approximate, obliquely jointed, of various lengths, giving
off ramules here and there ; HYDROTHECTE urceolate, dis-
tant, one to each internode, frequently wrinkled, swollen
below, narrower and divergent above, with a 4-toothed
aperture ; GONOTHEC^: elongate, ovate, tapering towards

238

SERTULARIID^E.

the aperture and the base, somewhat compressed, strongly
ringed above, the lower portion smooth — aperture small,
with two denticles.

THE S. Gayi of Lamouroux was regarded by Dr. Johnston
as a variety of the somewhat protean S. polyzonias ; but
after some consideration, I venture to restore it to specific
rank. In habit it is sufficiently distinct. The stems are
thick and coarse, made up of many fibres agglutinated
together, erect, and rigid, and wanting altogether the sub-
flexuous character of the allied species. They are pinnate,
the pinme springing alternately at regular intervals and
very close together, whereas in S. polyzonias the branches
are distant and irregularly distributed. The calycles differ
but slightly in the two species. Those of S. Gayi are
somewhat stouter, and frequently wrinkled transversely.
The capsules afford a good specific character. They are
rather smaller and more slender than those of polyzonias,
compressed, tapering very decidedly towards the apex,
and wanting the tubular orifice (Woodcut, fig. 29). The

Fig. 29.

aperture is smaller, and bears only two opposite denticles

SERTULARELLA TRICU SPED ATA. 239

on the margin, instead of tlie four teeth which occur in
the preceding species. The ringing, which is very marked,
covers only the upper third of the capsule, the inferior
portion being perfectly smooth.

S. Gayl ranges in height from about 4 to 10 inches. It
is a deep-water form. Pallas describes it, under his S.
ericoides, as " elegantissimam omnium varietatem."

Hub. Cornwall, not uncommon; climbing over Gor-
gonia, from 60 fathoms, off the Deadman; amongst the
refuse of the Plymouth trawlers (T. H.) : Isle of Wight
(Solander) : Norfolk and Suffolk (C.W. P.) : Durham and
Northumberland, occasionally in deep water (J. A.) : Pe-
terhead and Wick (C. W. P.) : Shetland (A. M. N.) :
Birterbuy Bay, Comiemara (G. S. Brady) : Dublin Bay.

[Coast of Normandy (Gay).]

3. S. TRICUSPIDATA, Alder.

SERTULARIA TRICUSPIDATA, Alder, North, and Durham Cat. in Trans. Tynes.

F. C. iii. Ill, pi. iv. figs. 1, 2.
„ ERICOIDES, Espcr, Pflanzth. Sertul. pi. xii. figs. 1, 2.

Plate XLVII. fig. 1.

STEMS slender, alternately branched, or divided dichoto-
mously, often bipinnate at the top, jointed above each
calycle, and twisted at intervals ; HYDROTHEC.E distant,
cylindrical, smooth, slightly expanded and everted above,
with a 3-toothed aperture : GONOTHEC.E large, strongly
ribbed across, with a plain funnel-shaped aperture, which
rises from the centre of a bowl-like expansion.

THIS species is separated from S. polyzonias by a group
of well-marked characters. It is of exceedingly delicate
habit, of a light brown colour, and attains a height of
about 2 inches. The mode of growth is irregular. Some-
times the branches are alternate, and often themselves

240

SERTULARIID^E.

Fig. 30.

much branched; sometimes the stems divide dichoto-
mously, and frequently terminate in a fork. The calycles
are narrow and cylindrical — not swollen at the base. The
rim of the aperture rises into three strong denticles, the
largest in front, and the others on the sides. The margin
is somewhat thickened.

The capsules, which are very large in proportion to the
size of the calycles, are less inflated than
those of polyzonias, and much more
strongly ribbed transversely. The sides
are cut into deep dentations between the
rings, which extend uniformly from top
to bottom. At the upper extremity
the capsule expands into a kind of
bowl, and from the centre of this rises
a narrow funnel-shaped aperture with a
plain rim.

S. tricuspidata has only been found
in the north. Amongst some dredgings,
obtained in 100 fathoms, near Reikiavik, in Iceland, it
occurs in great abundance and of unusual size. The spe-
cimens from this locality bear the reproductive capsules
in profusion, their branches being frequently laden with
them throughout their whole extent. They were taken
up amongst "icebergs, grounded and drifting." It is
probably this species which Mr. Busk has figured in the
' Microscopical Journal/ from a specimen procured in
Greenland, under the name of S. polyzonias.

Hab. Parasitical on other zoophytes, "from the deep-
water boats that supply Newcastle market with fish during
the spring months ; not rare" (J. A.).

[Off Reikiavik, Iceland (T. II.): Greenland (Busk):
Straits of Belle Isle, in 40 fathoms, abundant (A. S.
Packard, jun.) .]

SERTULARELLA RUGOSA. 241

4. S. RUGOSA, Linnaeus.

" SNAIL TREFOIL CORALLINE," Ellis, Cor. 20, tab. xv. figs. «, A.

SERTULARIA RUGOSA, Linn. Syst. 1308 ; Pall. Elench. 126 ; Exper, Pflanz.

Sert. tab. xi. figs. 1-4 ; Lamk. An. s. Vert. (2nd ed.) ii. 149 ;

Johnston, B. Z. i. 63, pi. x. figs. 4-6.
CLYTIA RUGOSA, Lamx. Cor. flex. 204.
SERTULARIA PATAGONICA, D' Orb. Amer. M6rid.
SERTULARELLA RUGOSA. Gray, List of Brit. Mus. Radiata, 69.
AMPHITROCHA RUGOSA, Agassiz, Nat. Hist. U. S. iv. 356.

Plate XLVII. fig. 2.

SHOOTS small, gregarious, simple or very sparingly and
irregularly branched; STEMS ammlated at the base and
between the calycles; HYDROTHEC^E crowded, barrel-
shaped, strongly wrinkled transversely, narrowed towards
the quadrangular aperture, which is set obliquely and
looking outwards, and is furnished with four very minute
denticles and a quadripartite operculum ; GONOTHECJE
very large, ovate, strongly ribbed across, with a -^-toothed
aperture.

THERE are two forms of this species. In the larger
and more luxuriant the creeping stem sends up nu-
merous crowded shoots, commonly less than an inch in
height, which are very scantily branched. They are bare
for some distance above the base, and strongly annulated.
Throughout the rest of their length they are covered with
the short barrel-like calycles, which are closely set, the
small intervening spaces being also more or less ringed.
The other is a dwarf variety.

t/

The capsules are three or four times as large as the
hydrothecse. They are generally described as having a
tridentate aperture ; but there are, I believe, four teeth,
one of much smaller size than the rest.

Hab. Most frequently parasitic on Flustra foliacca;
also on seaweed, zoophytes, &c., from low- water mark to
deep water ; common.

R

242 SERTULARIIDJE.

[Greenland (Fabricius) : North Cape, between tide-
marks (Sars) : Square Island, Labrador, in 30 fathoms,
rare (A. S. Packard, jun.).]

5. S. TENELLA, Alder.

SERTULARIA RUGOSA, var., Johnsf. B. Z. 64 & 62, fig. 8 c.

„ TENELLA, Alder, North. Cat. in Trans. Tynes. F. C. iii. 113,

pi. iv. figs. 3-6.

Plate XLVII. fig. 3.

ZOOPHYTE minute ; STEMS short, slender, simple or slightly
branched, zigzagged, and jointed and twisted above each
calycle; HYDROTHEC^E rather distant, elongate, barrel-
shaped, finely ribbed across, the aperture erect, patent,
squared, ^-toothed, and closed by a four-sided opercu-
lum; GONOTHEC.E ovate, slender, ringed transversely,
produced above into a short tubular orifice.

"Tflis pretty little species is smaller and more delicate
in all its proportions than S. rugosa, with which it has
hitherto been confounded. The cells are more erect,
narrower, and more closely and regularly ribbed or
wrinkled across, the wrinkles generally rising a little op-
posite each angle ; there are six or seven in this species ;
in S. rugosa three or four." .... In the latter " the
aperture is much less prominent, and always bent out-
wards." .... The cells of S. tenella " are more dis-
tant than those of S. rugosa/' in this respect resembling
S. polyzonias ; but they are more slender and elongated

than in either species The " polypes appear to be

yellow or orange-colour/'' (Alder.}

Hob. Northumberland, on Plumularia falcata and other
zoophytes, but not common (J. A.) : South Devon, be-
tween tide-marks; Filey, Yorkshire (T. H.) : Peterhead,

SERTULARELLA FUSIFORMIS. 243

occasionally (deep water) ; Wick, on other zoophytes
(C. W. P.) : Hebrides; Shetland, on Tubularia indivisa
(A.M.N.).

6. S. FUSIFORMIS, Hincks.

SERTULARIA FUSIFORMIS, Cat. Devon and Corn. Z. 11, pi. vi. figs. 7, 8, Annals
N. H. (3rd ser.) viii. 253, pi. vi. figs. 7, 8.

Plate XLVII. fig. 4.

STEMS slender, slightly zigzag, generally simple, annu-
lated at the base and below each calycle ; HYDROTHECJE
bent in opposite directions, elongate, somewhat flask-
shaped, smooth, one to each internode, aperture quadri-
dentate, operculurn composed of four pieces — each in-
ternode, with its calycle, of a fusiform figure ; GONO-
THECJS elongate ovate, slender, ribbed across, produced
at the upper extremity into a short neck, and toothed.

Height from -j- of an inch to 1 inch.

THIS minute zoophyte presents the appearance of a
series of fusiform pieces, springing one from the side of
the other about midway, and bending alternately in op-
posite directions. Its nearest ally is the S. tenella. It
is one of the company of pigmy forms, as exquisite as
they are minute, which reward a diligent search amongst
the chinks and crannies of the tidal pools.

Hab. Between tide-marks, on rocks, South Devon;
under one of the lower ledges, Capstone, Ilfracombe
(T. H.) : Torbay (E. Parfitt) : Hebrides (A. M. N.).

R 2

244 SERTULARIIDJE.

Genus DIPHASIA, Agassiz.

SERTULARIA (auct.) (in part).
BYNAMENA, Lamouroux (in part).

GENERIC CHARACTER. — Zoophyte plant-like ; stem more
or less branching, jointed, rooted by a creeping stolon; hy-
drothecte opposite, a pair on each internode, occasionally
subalternate, with an internal, valve-like operculum ; gono-
thecas scattered, differently shaped in the two sexes — the
female ample, more or less cleft or divided into segments
above, containing a marsupial chamber ; the male smaller,
with a central tubulous aperture.

OF this beautiful genus D. rosacea may be taken as the
type; it strikingly represents the characteristics of the
group. Diphasia agrees generally with one section of the
genus Sertularia in the arrangement of its calycles ; but
they are furnished with a plain or rarely an obscurely
toothed aperture, while in the latter they are decidedly
bilabiate or rnucronate. But the chief distinction is
found in the structure of the reproductive capsules, which
exhibit great uniformity throughout the genus, and differ
essentially from those of the allied groups.

In all the species of Diphasia the female gonotheca
encloses a more or less spherical chamber or marsupium,
which surmounts the axial column, and into which the
contents of the several sporosacs are successively dis-
charged (Plate XLVIII. fig. 1, d) . The uppermost portion
of the capsule, immediately surrounding this chamber, is
always cleft or divided into segments, either free or slightly
adherent, which open for the passage of the planules when
mature. The external form varies in the different species ;
but these points of structure are constant.

The male gonotheca exhibits universally the same general
figure. It is usually much smaller than the female, and

DIPHASIA ROSACEA. 245

in the centre of its upper surface there is always a raised
tubular orifice, which is surrounded by several spinous
projections.

This genus has been named by Agassiz, but he has
given no definition of it; he merely refers to the cleft
border of the gonotheca as the prominent feature. He
has ranged under it nearly all our British species, but
wrongly associates with them Sertularia fusca, which is
referable to a very different type.

1. D. ROSACEA, Linn.

" LlLY OR POMEGRANATE-FLOWERING CORALLINE," EH'tS, Cor. 8, pi. iv. figS. fl, A.

SERTULARIA KO.SACEA, Linn. Syst. 1306 ; Esper, Pflanz. Sert. tab. xx. figs. 1-3 ;
Lamk. An. s. Vert. ii. 119 ; Johiist. B. Z. 64, pi. xi. fig. 1 ; 468.
fig. 83.

„ NIGELLASTRUM, Pall. Elench. 129.

DYNAMENA ROSACEA, Lamx. Cor. flex. 175.
DIPHASIA ROSACEA, Agassis, iv. 355.

Plate XLVIII. fig. 1.

SHOOTS very slender and delicate, of a white or pale horn-
colour, branched, the branches alternate, distant, un-
equal, internodes constricted at the base ; HYDROTHEC^E
long and tubular, the upper portion free and more or less
divergent, aperture oblique, entire ; GONOTHECA (female)
pear-shaped, tall, shortly stalked, ivith eight longitudinal
ridges, terminating above in spinous processes of various
lengths, the outer one on each side much the longest,
lanceolate, incurved, with a notch on the outer edge,
the remainder short, crowded, and converging towards
the central aperture; (male) pyriform, curved towards
the base, traversed by longitudinal lamellated ridges,
which rise above into spinous points around a slender
tubular orifice.

S. ROSACEA is remarkable amongst its kindred for slender-
ness of habit and for its delicate, papyraceous texture. It

246 SERTTJLABIIDJE.

is generally of a pellucid whiteness, and throws about its
stems and branches in the most graceful curves.

There is some variation in the degree in which the free
portion of the calycle diverges; in some specimens it
bends abruptly outwards, in others it rather inclines up-
wards. The internodes also are more or less produced and
attenuated below, and are often much constricted at the
joint. The operculum of the calycle is placed a little
below the aperture, and shows distinctly through the deli-
cate walls, giving the appearance of a transverse fold or
crease.

The gonothecse* in an early stage are in the form of an
inverted cone, traversed by eight longitudinal ridges that
terminate above in as many angular projections (Plate
XLVIII. fig. 1, c]. In the perfect state, the female capsule
encloses an oval marsupial chamber, formed by eight ra-
diating, chitiiious tubes, which originate at the summit of
the column bearing the ovarian sacs. The ova are trans-
ferred from these sacs successively into the chamber, and
there pass through the later stages of their development f.
Airman describes the male gonothecce as having only six
of the longitudinal ridges ; but in all that I have examined
there were eight, as in the female. There are generally
from four to six sperm-sacs in each, forming a row, which
extends to the very top of the cavity.

The capsules are sometimes borne in continuous lines
along the upperside of the pinnse, springing from the base
of each pair of calycles.

Hab. On other zoophytes (chiefly) and on shells ; gene-

* " Large and peculiar vesicles, alike difficult to be described and repre-
sented, are borne by the Sertularia rosacca." — Dali/ell.

t Fide Prof. Allman's " Eeport on the Reproductive System in the Hy-
droida," Eeport Brit. Assoc. for 1863, pp. 372-3.

Lieut. Thomas also has given a very accurate account of the structure of
the gonotheca, in the Supplement to Johnston's ' Zoophytes,' pp. 468-9.

DIPHASIA ATTENUATA. 247

rally distributed. It ranges from between tide- marks to
deep water.

[Very abundant in 50 fath., gravelly bottom, in the
Straits of Belle Isle (A. S. Packard, jun.): Massachusetts
Bay (Agassiz).]

2. D. ATTENUATA, HillclvS.

SERTULARIA ROSACEA, Ellis, Cor. 9, pi. iv. fig. C?; Juhnst. B. Z. 470 (speci-
men from Orkney, Lieut. Thomas).
„ PINASTER, var., Johnston, B. Z. 72, figs, c, d.

„ ATTEXUATA, HincJcs, On new British Hydroida, Annals N. H.

for October 18C6, (3rclser.)xviii. 298.

Plate XLIX. fig. 1.

STEMS straight, somewhat rigid, pinnately branched, often
running out above into long tendril-like filaments, which
are thickened and bifid at the extremity; branches simple,
or bearing one or two ramules, alternate, inclined upwards,
sometimes furnished with tendrils ; HYDROTHEC.E tubu-
lar, slender and gracefully curved, about half their length
free and divergent, but not abruptly bent, with a plain,
suberect aperture ; GONOTHEC.E (female) elongate-pyri-
form, tapering off below, and gradually expanding up-
wards, bristling with strong spines above, which are
arranged on six longitudinal ridges, and extend down the
upper third of the capsule ; (male) ovate, with six longi-
tudinal ridges, terminating above in angular points, the
aperture subconical, rising in the midst of them.

THIS pretty species has been confounded with D. rosacea,
to which it bears some general resemblance. The habit
and texture of the two, however, are strikingly distinct ;
so are the reproductive capsules, and there are also dif-
ferences, though minute, in the form and arrangement of
the calycles. D. attenuata is more robust and rigid and

248 SERTULARIID^E.

of larger growth than its ally, and wants its delicate, mem-
branaceous texture. The calycles do not shrivel in drying as
those of D. rosacea do. The stems are much firmer, and
of a decided horn-colour; they are commonly furnished
with long tendril-like extremities. These are occasionally
met with on D. rosacea as on other species, but they are
very characteristic of D. attenuata. The tendrils are com-
posed of a number of oblong pieces separated by joints
(Plate XLIX. fig. 1, d) .

The branches are often long and slightly curved up-
wards, and exhibit the same comparative rigidity as the
main shoots. It is more difficult to describe the differences
in the calycles. Those of D. attenuata are longer and
more slender, and slightly suberect towards the aperture,
which is smaller and less "flaring" than in the allied
species ; they curve gracefully and gradually outward, and
do not bend abruptly. But the chief distinction is to be
found in the gonothecse, which seem almost top-heavy
with their profuse garniture of spines, some of them long,
slender, and acuminate, others shorter and stouter, and
wrinkled transversely. There are generally three on each
ridge, the uppermost being the largest and rising con-
siderably above the aperture. The capsules are sparingly
produced.

After entering into these details, it must be added that
what may be called the egression of the species will enable
the student readily to recognize D. attenuata. Its erect and
somewhat stiffer habit, its decided horn-colour contrasting
with the pearly whiteness of rosacea, its slenderer branches,
its more erect and regularly pinnate form, and its long
tendrils will at once betray it to a quick eye.

This form has been noticed by several previous authors,
but has been accounted a mere variety. Ellis has figured
it Avith the female capsule, referring it to rosacea (pi. iv.

DIPHASIA EALLAX. 249

fig. C). Dr. Johnston's woodcut (fig. 12, c, d, page 72)
represents the male, which he strangely identifies with
pinaster, in spite of the totally different calycles ; and
Couch evidently refers to it when he says, in his remarks
on D. rosacea, " In a specimen before me the gemmules,
though ripe, are not yet excluded, and the spines not only
surround the upper edge of the vesicle, but are scattered
over one-third of the upper surface " *.

Hab. Generally on other zoophytes ; Ilfracombe ; Swan-
age, Dorset, common; Filey; Whitby (T. H.): Gorran
Haven, Cornwall ; Peterhead (C. W. P.) : Brighton (Ellis) :
South Devon (Parfitt) .

[In Mr. Busk's collection there is a fine specimen from
Port Adelaide, about an inch in height.]

3. D. FALLAX, Johnston.

DYNAMENA PINNATA, Ffcm. Br. An. 545.

SEKTULARIA PINNATA, Jolmst. B. Z. (1st ed.) 127, pi. ix. figs. 5, 6.
,, FALLAX, Johnst. B. Z. (2nd ed.) 73, pi. xi. figs. 2, 5, 6.
DIPHASIA FALLAX, Agassiz, N. H. U. S. iv. 355.

Plate XLIX. fig. 2.

STEMS thick, pinnate; branches alternate, sparingly branch-
ed, springing from the front of the stem and arching
outwards — the main shoots and many of the branches
terminating in tendril-like claspers ; HYDROTHEC^E shortly
tabular, the upper part free for a little way and slightly
divergent, with a wide plain aperture, the inner margin
of which is somewhat sinuatcd ; GONOTHEC^E (male) elon-
gate, slender, tapering towards the base, expanding up-
wards and bearing four stout and erect spines, which
surround the raised tubular aperture; (female) ovate,
deeply cleft above into four convergent leaf-like segments.

* Cornish Fauna, part. iii. p. 19.

250

SERTULAUILD^E.

IN its ordinary condition D. fallax presents an elegant
plumous form, the main shoots being often gracefully re-
curved, and the branches arching outwards from their
point of departure on the front aspect of the stem. The
large number of tendrils, elegantly curled and thickened
at the extremity, with which it is furnished, give it a very
marked and peculiar appearance. No other species rivals
it in this respect. The stems are often dark-coloured.
Luxuriant specimens occur in which the simple plume-
like aspect altogether disappears, and the main stem is
thickly set with long branches, each of which is itself
pinnate. An example of this kind now before me, which
is 2 inches high, has more than a dozen plumous branches
down each side, and is provided with between thirty and
forty of the tendril-like filaments. This species is of a
delicate whiteness when fresh, but becomes dark-coloured
in drying, and in this state has usually a glossy or var-
nished appearance. The male capsule has not hitherto
been described. It is, as usual, much smaller than the
female, and presents the general appearance which is cha-
racteristic of this sex throughout the genus (Woodcut,

a

fig. 31). The female capsule contains a somewhat spheri-
cal marsupial chamber, embraced by a number of tubular

DIPHASIA FALLAX. 251

processes, and protected by four long and pointed seg-
ments, into which the upper part of the capsule is cleft.
These originate a good way down, and may be traced in
an early stage of the development ; they are not adherent,
but converge above and so close the aperture, opening
readily for the passage of the embryo. We have here a
modification of the structure already described in the case
of D. rosacea. The circulation of the nutrient fluid may
be traced in the tubes which surround the marsupium. I
have seen as many as six finely ciliated planules moving
freely about within the cavity of the sac.

A specimen in my possession bears capsules of both
sexes, the female occupying the upper portion of the
shoot, and the male being distributed over the lower
branches, — another case of departure from the dioscious
condition which is usual amongst the Hydroida.

Hub. Commonly parasitic on other zoophytes, to which
it binds itself by means of its numerous tendrils. It is a
northern species, ranging from the coast of Yorkshire to
Shetland, and an inhabitant of deep water. Filey, abun-
dant (T. H.) : Scarborough (Mr. Bean's collection con-
tains very splendid specimens, composed of many large
shoots united together) ; Northumberland and Durham,
frequent (J. A.) : Firth of Forth, plentiful (Dr. Cold-
stream) : Loch Fyne (A. M. N.) : coast of Aberdeen
(Macgillivray) : Peterhead, plentiful ; Wick, much rarer
(C. W. P.): Orkney Islands, 35 fathoms; Buchanness,
40 fathoms (Lieut. Thomas): Hebrides; Shetland, 40
fathoms (A. M. N.).

[Tromso, in 30 fathoms, rare ; commoner at Bergen on
stems of Laminaria (Sars) : Grand Manan ; " a few speci-
mens, probably of this species, were taken in deep water'3
(Stimpson) : Massachusetts Bay (Agassiz).]

252 SERTULAEILD.E.

4. D. PINASTER, Ellis & Solander.

SERTULARIA PINASTER, Ellis 8f Solander, Zooph. 55, t. vi. fig. 6 B ; Johnxt.

B. Z. 71, 72, fig. 12 a,b; Alder, Northumb. Cat. in Trans.

Tynes. F. C. iii. 114.

DYNAMENA PINASTER, Lamx. Exp. Meth. 12, t. vi. figs, b, B.
DIPHASIA PINASTER, Agassis, N. H. U. S. iv. 355.
SERTULARIA MARGARETA (the female), Hassall, Ann. & Mag. .N. H. vii. 284,

pi. vi. figs. 3, 4 ; Johnst. B. Z. 72, 73, fig. 13 ; Hincks, Devon

and Cornw. Cat., Ann. N. H. (3rd ser.) viii. 254.
DIPHASIA MARGARETA, Agassiz, N. H. U. S. iv. 355.

Plate L. fig. 1.

STEMS erect and somewhat rigid, regularly pinnate ; pinna?
alternate, often of great length, with occasionally a few
hranchlets ; HYDROTHEC.E tubular, the inferior half adhe-
rent, the superior abruptly divergent and slightly curved
upwards, with a distinct fold at the point of divergence ;
aperture plain and circular; GONOTHEC^: (male) ovate,
subpedicellate, quadrangular above, each angle produced
at the top into a spine ; (female) oval, shortly stalked,
domed above, with four longitudinal ridges and eight
spines borne on the ridges and arranged in two circles,
one near the top and the other somewhat lower down.

Two species have been made out of this well-marked form,
founded on mere differences of sex, which had not been
recognized when Dr. Johnston's work was published. The
Sertularia Margaret a of Hassall is the female of the S.
pinaster described and figured by Solander. This species
is of somewhat rigid habit, and, when dried, of a light
horn-colour. When fresh it is of a delicate pearly white-
ness, and when laden with the yellow capsules, which
stand erect in rows along the pinna?, is a most beautiful
object. The creeping stem sends up pinnate, plume-like
shoots from 2 to 6 inches high, that are either single or
bear similar shoots at irregular intervals, which, as Dr.
Johnston well said, " appear rather to grow on the rachis

DIPHASIA PINASTER. 253

than to grow out of it." Occasionally the main stem
divides dichotomously very near the base, each arm
dividing again, and sometimes subdividing in the same
fashion, so as to form a compound specimen. Sometimes
a tall stem, pinnate at the top, but bare throughout the
greater portion of its length, carries a number of long
plumous shoots, springing from it in various directions,
so as to give a very straggling habit to the whole. The
pinnae occasionally bear a few branchlets, but arc more
generally simple. Under every variety of growth this
species may be recognized by its calycles. The abrupt
divergence of the upper half causes a somewhat deep
central depression in the outer edge, which is accompanied
by a distinct fold. The divergent portion curves outwards
and is slightly concave on the superior side.

As usual, the female capsules are much larger in all
their dimensions than the male; they are both borne
along the upperside of the branches and at the base of
the calycles.

Hab. There has been so much confusion respecting this
species, that localities must be taken with caution. It
seems, however, to be widely distributed.

Shetland ; Hebrides (A. M. N.) : off Sana Island, in
40 fathoms (Hyndman): Clyde district (Forbes): Oban
Bay, abundant (T. H.) : Arran (Landsb.) : off the Mull
of Galloway, in 110-140 fathoms (Capt. Beechey) : Em-
bleton Bay, Northumberland, deep water (R. Embletou) :
Dogger bank (J. A.) : Mersey (Tudor and Dr. Colling-
wood) : Devonshire (Mrs. Griffiths) : Jersey (A. M. N.) :
Ireland, Belfast Bay (Hyndman): Dublin Bay (W. T.):
Giants' Causeway (Hassall).

254 SERTTJLARIID^E.

5. D. TAMARISCA, Linnseus.

"SEA TAMARISK," Ellis, Corall. 4, pi. i. figs, a, A.

SERTULARIA TAMARISCA, Linn. Syst. 1307 ; Pall. Elench. 129 ; Lamx. Cor.

flex. 188; LamTc. An. s. Yert. (2nd ed.) ii. 153; JO^HS?!. B. Z.

74, pi. xiii. figs. 2, 3, 4.
DYNAMENA TAMARISCA, Flem. Br. An. 543.
DiniASiA TAMARISCA, Agassiz, N. H. U. S. iv. 355.

Plate LI.

SHOOTS stout and erect, irregularly branched, the branches
commonly alternate, sometimes opposite, long, simple
or variously branched ; HYDROTHEC^E very large, cylin-
drical, the upper half free and divergent, with a wide,
tridentate aperture ; GONOTHEC^E (male) compressed, ob-
cordate, attenuated below, broad and truncated above,
with a small spine at each side, and a central tubular
aperture; (female) elongate, oval below, above three-
sided, with a pyramidal summit, the edges of the pyramid
serrated, and its basal angles produced into spines.

D. TAMARISCA is distinguished by its robust habit and the
large size of its tubular calycles, which give a strongly
serrated appearance to the stems and branches. They are
of a thin, transparent, corneous texture. The ramification
is irregular — long, simple branches alternating with others,
which are pinnate or bipinnate. The branches frequently
do not lie in the same plane as the stems, but spring from
them in various directions, so as to give a somewhat
shrubby appearance. The mode of growth is straggling
and irregular.

The capsules are produced abundantly, and often line the
branches in conspicuous rows. The male and female are
commonly borne, it would seem, on distinct colonies ; but
this is not universal, as I have a specimen on which they
are intermingled. The former, which alone were known
to Ellis and Johnston, are somewhat in the shape of a
heart, attached by its pointed end. The tubular orifice

DIPHASIA PINNATA. 255

rises in the centre of the upper extremity, which is broad
and truncate, and produced at each side into a more or
less developed spine. They are often slightly furrowed
transversely. The male capsules form rows on the bran-
ches, partly overlapping one another.

The female capsule is of much larger size, and presents
a complex internal structure, which has been minutely
described by Professor Allman*. It consists of two
chambers, the lower of which is traversed by the column
bearing the ovaries. This is surmounted by an upper
story, which encloses a marsupial sac, surrounded by a
number of branched ctecal tubes. The portion of the
capsule which forms a protective case for the marsupimn
is composed of three detached pieces that converge above.
The summit is pyramidal. After the liberation of the
embryos the top of the capsule presents a very ragged
appearance.

D. tamarisca often attains a large size.

Hab. On shells and stones from deep water. Though
not an abundant species, D. tamarisca is very widely dis-
tributed. It occurs in Ireland.

[La Charente Inferieure, Bay of Biscay, common
(Beltremieux) : Grand Manan (Stimpson) : Massachusetts
Bay (Agassiz) .]

6. D. PINNATA, Pallas.

SERTULARIA PINNATA, Pallas, Blench. 136 ; Johnst. B. Z. 69, pi. xii. figs. 3, 4,

and woodcuts, 69. figs, b, b.

„ FUSCESCENS, Turt., Gmel. iv. 677; Lamx. Cor. flex. 195.
NIGELLASTRUM piNNATUM, Oken, Lelirb. Nat. 93.
DIPIIASIA PINNATA, Agass. N. H. U. S. iv. 355.

SERTULARIA NIGRA (the female), Pall. Elench. 135 ; Johnst. B. Z. 68, pi. xii.
figs. 1 & 2, and woodcuts, 69. figs, a, a.

* " Eeport on the Reproductive System in the Hydroida," British Assoc.
Report for 1863, pp. 373-4.

256

NIGELLASTRUM NiGRUM, OJcen, Lehrb. Nat. 93.
DIPHASIA NIGRA, Agass. N. H. U. S. iv. 355.

Plate LII.

SHOOTS pinnate, somewhat lanceolate, deep red or pink when
living, drying black or reddish brown; STEMS straight,
tapering towards the tip, compressed, delicately serrated ;
pinnce simple, alternate or sometimes opposite, not
constricted below the calycles, much attenuated towards
the base, often greatly elongated ; HYDROTHEC^E subal-
ternate, or sometimes opposite, small, crowded, tubulous,
adherent, slightly everted at the top, with a wide, even
aperture ; GONOTHEC^E (male) ovate, tapering to a blunt
point below, with a number of short denticles at the top,
round the central papillary aperture; (female) ample,
subsessile, smooth and varnished, obovate, divided by longi-
tudinal lines, which meet at the apex, into four lobes.

THE Sertularia pinnata and S. nigra of Pallas must be
united as one species, the only differences between them
being dependent upon sex. The former specific name,
which Pallas applied to the male, and which is preferable
in itself, may be retained.

The shoots, which attain a height of 6 inches or up-
wards, spring from the midst of a twisted and tangled
mass of fibres, which sometimes involves the lower part
of the stem for a considerable distance*. A sheaf of many
plumes is often bound together at the base in this way.
The species varies in habit. In some cases the shoots are
plumous in form, elongate and slender; in others the
pinnse are enormously produced, giving a breadth of as
much as 3 inches. The pinnae taper off very finely to-
wards the point of origin, becoming suddenly thicker
above it, and continuing of equal width to the extremity.
There is no constriction below the calycles as in all the

* Tubi intestinuliformes, implexi, usque ad pinnarum originem sissurgen-
tes."— Pallas.

DIPHASIA PINNATA. 257

preceding species ; D. pinnata deviates in this respect from
the typical character of the genus. Its hydrothecse are
not arranged in pairs, separated from each other by a dis-
tinct joint, but are closely arranged along each side of the
branches in slightly alternate order.

Specimens when dried lose their brilliant colouring
(which is due to the presence of the animal pulp) , and
become black, sometimes with a tinge of red, and varnished.

The capsules are produced in immense profusion, often
forming rows along the upperside of almost every pinna,
and giving the zoophyte much the appearance of a minia-
ture tree heavily laden with fruit. The female gonotheca,
which is three times as large as the male, presents a struc-
ture analogous to that which has been described in several
of the preceding species. It is lobate, and the segments,
which are closely adherent at first, separate as the embryos
reach maturity.

This is unquestionably one of the finest of the British
Sertulariidae . We owe the first description of it to Pallas,
who, in his 'Elenchus/ has characterized it with the
minute accuracy that distinguished him.

Hab. D. pinnata seems to be confined to the south-
western district, occurring not uncommonly, at consider-
able depths, in the warm waters which bathe the shores of
Cornwall and South Devon.

The Lizard (Pallas) : off the Deadman, rare ; a few
miles west and north-west of the Eddystone, common
(R. Q. C.) : Coast of Devon (Mrs. Griffiths) : Polperro, in
40 fathoms, 10 or 12 miles from shore (Laughrin). I
have received many specimens from this part of the
Cornish coast.

[In Mr. Busk's collection there is a specimen with the
male capsules from Sydney, and one with the female from
South Africa.]

258 SERTULARIIDJS.

7. D. ALATA, Hincks.

" Notes oa British Zoophytes," Ann. & Mag. N. H. for February 1855,(ser.2)
xv. 127, pi. ii.

Plate XLVIII. fig. 2.

ZOOPHYTE blackish brown, highly varnished; STEM straight,
rather thick, pinnate; pinnae alternate, approximate,
long, not constricted below the calycles, keeled along one
side, and attenuated towards the base; HYDROTHEC.E
elongate, adherent for about two-thirds of their length,
the upper part suddenly divergent, wide, rounded below,
concave above, aperture oblong, the outer margin everted ;
GONOTHEC.E (male) very small, tapering towards the
base, subquaclraugular above, with a mucro, which bends
inwards at each corner; (female) unknown.

Height from 3 to 5 inches.

THIS species is closely allied to the Sertularia mutulata,
a native of Torres Straits, described by Busk in 'The
Voyage of the Rattlesnake/ The only form of gonotheca
hitherto found on it is characteristic of the male sex
throughout this genus. The hydrothecse are minute ; the
free portion is abruptly divergent, and stands out like a
bracket from the stem.

The shoots of D. alata are regularly pinnate, and the
pinnae are almost always simple. They are not constricted
below each pair of calycles, as in most of the other mem-
bers of the genus, but of uniform thickness through a
great portion of their length, becoming slightly attenuated
towards the base. A prominent keel runs down the centre
of each pinna on one of its aspects and of the main stem.
The colour of D. alata when dried is very dark, and the
surface highly polished.

Hab. Shetland (Barlee) : one mile north of Whalsey
Lighthouse, Shetland, in 40 fathoms, rare; Hebrides
(A. M. N.): Falmouth (Cocks): Cornish coast (C. W. P.).

SERTULABJA.

259

Genus SERTULARIA, Linnaus (in part) .

DYNAMENA, Lamouroux (in part).
AMPHISBETIA, Agassiz (for S. operculata).

GENERIC CHARACTER. — Zoophyte plant-like; stems more
or less branching, jointed, rooted by a creeping stolon; hy-
drothecae biserial, opposite, or alternate, without external
operculum ; gonothecce. scattered, with a simple orifice, and
without an internal marsupium.

Fig. 32.

THE genus Dynamena was constituted by Lamouroux
for the Sertulari<B which have the calycles opposite and
in distinct pairs (Woodcut, fig. 32) . Of
this group one section is now referred
to Diphasia; and I can see no valid
reason for separating the remaining
species from those with alternate and
subalternate calycles. The character
relied upon by Lamouroux as diagnostic
is a very shadowy one. In such a spe-
cies as Sertularia filicula, the hydro-
thecse are commonly opposite, but they
are also in many cases subalternate.
On some shoots they occur regularly in
pairs, and usually with a joint between
each pair, as in S. pumila; on others
they alternate slightly, and as many as six are borne on
an internode. If the genus Dynamena were adopted, S.
filicula must be referred to it*, and would thus be separated
from S. abietina, to which it is clearly most closely related.
It is impossible to draw a boundary line satisfactorily ; and

* So Kirchenpauer places it, in a recent paper (1864), in which he has
argued for the retention of Lamouroux's genus.

s 2

260 SERTTJLABIID^:.

I therefore blend the two groups under the old Linnaean
name.

Without the examination of a much larger number of
foreign species, the genera of this family cannot be defined
with certainty and precision; and the present grouping
must be accepted as, to some extent, provisional.

Sertularia is a cosmopolitan genus, and a large number
of species have been described.

With opposite calycles [Dynamena, Lamx.].

1. S. PUMILA, Linnaeus.

" SEA-OAK CORALLINE," Ellis, Corall. 9, pi. v. figs, a, A.

SERTULARIA PUMILA, Linn. Syst. 1306; Pallas, Elench. 130; Esper, Pflanz.

Sert. t. x. figs. 1, 2 ; Lamk. An. s. Vert. (2nd ed.) ii. 145;

Lister, Phil. Trans. 1834, 371, pi. viii. fig. 3; Johnst. B. Z.

66, pi. xi. figs. 3, 4.
DYNAMENA PUMILA, Lamx. Bulletin Soc. Philomatique, 1812, iii. 184; Cor.

flex. 179 ; Flem. Brit. An. 544 ; Agassis, N. H. U. S. iv 355.
SERTOLARA PICCINA, D. Chiaje, An. s. Vert. Nap. iv. 142.

Plate LIII. fig. 1.

SHOOTS crowded on the creeping stolon ; STEM straight or
gently curved from base to tip, simple or ramified;
branches opposite, and in luxuriant specimens them-
selves branched ; both stem and branches divided by
joints into short internodes, each of which, with its pair
of calycles, forms a V -shaped figure; HYDROTHEC^E op-
posite, shortly tubular, free above for about a third of
their length, narrowed towards the aperture, which is
bent outwards and more or less cleft and mucronated ;
GONOTHEC^: (female) irregularly ovate, subsessile, with a
tubular rim ; (male) more slender and regularly oval.

S. PUMILA, the commonest of our littoral zoophytes, covers
the fronds and stems of the various larger Fuci with dense
miniature forests, and occurs on all parts of the coast. It

SEBTULARIA PUMILA. 261

is usually of very humble size, not rising to a greater
height than half an inch. In favourable situations, how-
ever, it attains a more luxuriant growth, sending up shoots
of twice or three times the height, which are variously
branched. Agassiz says that the specimens obtained near
low- water mark are commonly "the most luxuriant, and
more or less branching, while those at higher levels are
quite simple."

S. pumila is of a dusky horn-colour and somewhat close
texture. The polypite, which is long, slender, and grace-
ful, has about 16 tentacles. The capsules are produced
abundantly both on the main stems and branches, and
often occur in continuous rows of considerable length.
The female contains a single sporosac, whence the ova,
which are very numerous"*, are discharged into an exter-
nal marsupium, protected by a gelatinous investment, in
which they complete their development.

The breeding-season, according to Agassiz, extends from
May to September.

Judging from the figures given by this author, there is
but little difference between the male and female gono-
thecse in shape, the former being somewhat slighter and
more regularly oval. S. pumila is one of the phospho-
rescent species. If a frond of Fucus on which it is growing
" receive a smart stroke in the dark, the whole coralline is
most beautifully illuminated, every denticle seeming to be
on fire"t-

Hab. Between tide-marks, chiefly on the larger Fuel,
generally distributed. This zoophyte is met with on the
most barren shores.

[Greenland (Fabricius) : Lofoten and Finmark, common
on Fucus vesiculosus, F. nodosus, and F. serratus, to the

* '• Ovarium ovis plenissimum." — Pallas.

t Stewart, Elem. Nat. Hist, ii. 441, quoted in Johnston s Brit. Zooph.

262 SERTULARIID^.

North Cape (Sars) : Straits of Belle Isle, abundant between
tide-marks (A. S. Packard, jun.) : Nova Scotia (Dawson) :
Grand Maiian (teste A. Agassiz) : Massachusetts Bay
(Agassiz) : Coast of Belgium (Van Ben.) : common at
Naples, from between tide-marks to 1 or 2 fathoms depth,
where it often grows on Caulinia oceanica ; the calycles
longer and slenderer below than in the northern form
(Sars), ? S. gracilis : La Charente inferieure, very common
(Beltremieux) : Mossel Bay, South Africa (Krauss) .]

2. S. GRACILIS, Hassall.

SERTULARIA PUMILA, \&v.,Johnst. B. Z. 67 : var. (3, F. W. L. Thomas in Johnst,

B. Z. 469.
„ GRACILIS, Hassall, MS.

Plate LIU. fig. 2.

STEM extremely delicate and transparent, filiform, simple,
the internodes long, slender, and tapering, often twisted
towards the base; HYDROTHEC^E opposite, tubular, the
upper half free and divergent, narrowed towards the
aperture, which is small and produced into two opposite
mucronated points, between which on one side the rim has
a slightly angular projection; GONOTHEC^E ovate, smooth,
with a very short tubular neck, slightly marginate.

Height about \ inch.

THIS species is only about half the size of its ally, S. pumila,
and much more delicate in all its parts ; it is also light-
coloured and perfectly transparent. The internodes are
elongate and slender, and taper off decidedly below, where
there is generally a twist or fold. There is little difference
in the calycles, except in size. A larger proportion of the
length is usually free in gracilis than in pumila ; but this
is a variable character.

The capsule has a much narrower neck,, and is less de-

SERTULARIA OPERCULATA. 263

cidedly rimmed, than in the preceding species. S. gracilis
has a wider range than S. pumila, and is not an exclu-
sively littoral form.

Hob. Brighton, on algae (Hassall): Norfolk and Corn-
wall (" delicate var. of pumila") (C. W. P.): Swanage Bay,
Dorset, abundant on H. falcata &c. ; Lulworth, on stone ;
Ilfracombe (T. H.): Durham coast; Shetland (A. M. N.) ,

3. S. OPERCULATA, Liunasus.

" SEA-HAIR," Ellis, Corall. S, t. iii. figs. 4, B.

SERTULARIA OPERCULATA, Linn. Syst. 1307 ; Espcr, Pflanz. Sert. t. iv. figs. 1,2;
LamJc. An. 8. V. (2nd ed.) ii. 144; Johnst. B. Z. 77, pi. xiv.
figs. 2, 2.

,, USNEOIDES, Pall. Elench. 132.
DYNAMENA OPERCULATA, Lainx. Cor. flex. 176.

„ PULCHELLA, D' Orbigny.
AMPHISBETIA OPERCULATA, Agassis, N. H. U. S. iv. 355.

Plate LIY.

SHOOTS long, very slender, filiform, slightly jlexuous, branch-
ed ; the branches alternate, dichotomous, often much ra-
mified, erect; HYDROTHEC^E opposite, small, somewhat
obconic, the aperture sloping inwards towards the stem,
its outer angle produced into a very fine and sharp point,
which is slightly incurved, and with a minute denticula-
tion on each side ; GONOTHECJE obovate, smooth, with a
plain circular aperture.

ELLIS'S name for this species, "the Sea-hair Coralline," is
sufficiently expressive of its slender, wavy habit. It
grows in tufts, several inches high, many shoots rising
together and giving off long, ramified branches, so as to
form very large tangled masses. The branches are dicho-
tomous and decidedly erect, and in each axil there is an
inconspicuous calycle. The hydrothecae are minute, and
with their acute projecting points give a decidedly serru-
late appearance to the stems and branches. Of the lateral

264 SERTULARILDJE.

denticles, one is often absent or nearly obsolete, whilst the
other is developed to a length equalling that of the prin-
cipal mucro, which thus appears bifid.

The capsules, which are large, elongate, subsessile, ovate
above and tapering off below, are irregularly and profusely
distributed. They are furnished with a circular lid, that
opens as the contents are matured, and remains attached
by a portion of its margin, which acts as a hinge. They
bear a close resemblance, as Ellis has observed, to the
elegant seed-vessels of some of the mosses.

S. operculata is often prettily festooned by tufts of
Crisia eburnea, and studded with the small, silvery patches
of Cellepora Hassallii. It is sometimes tinged with red.

Hob. On Fuel) at and a little beyond low-water mark ;
generally distributed. It has a special liking for Lami-
naria digitata, the stems of which it often clothes with a
dense, tangled thicket.

[The species has a wide range. Belgium (Van Ben.):
La Charente inferieure, Bay of Biscay, pretty common
(Beltremieux): South Africa (Busk) : Patagonia; the Falk-
land Islands ; the Auckland Islands ; Australia ; New
Zealand; Kerguelen's Land.]

4. S. FILICULA, Ellis and Solander.

SERTULARIA FILICULA or FERN CORALLINE, Ell. 8f Soland. Zoopb. 57, pi. vi.
figs, c, C ; Lanik. An. s. Vert. (2nd ed.) 146 ; Lamx. Cor.
flex. 188 ; Johnston, B. Z. 76, pi. xiv. fig. 1.
,, ABIETINA j3, Pall. Elench. 134.

DYNAMENA FILICULA, Flem. Br. An. 544.

Plate LIII. fig. '3.

ZOOPHYTE composed of long, irregularly branched, luxuriant
shoois ; STEMS pinnate, slender, flexible, bent at short
intervals into alternate angles ; pinnae crowded, springing

SERTULARIA FILICULA. 265

from every bend, short and simple, or much elongated
and composite; HYDROTHEC^E minute, opposite or sub-
alternate, flask-shewed, the aperture oblique and facing
towards the stem, with a plain rim, — a single calycle
standing erect in every axil; GONOTHEC.E pear-shaped,
with a short, tubular aperture.

S. FILICULA is of delicate, wavy habit and a somewhat
bright straw- colour, and is one of the prettiest of its tribe.
It is generally luxuriant in growth, and presents a complex
ramification. It is cast on shore in large, tangled masses,
and may be known at once by its zigzag stems, its peculiar
colour, and its exquisite delicacy. The flask-shaped caly-
cles, too, with the bent apertures, one of which stands
erect in each axil, afford a good distinctive mark.

Amongst the spoils of the shore, there are few things
prettier than this zoophyte, and, familiar as it is, I never
cease to admire with fresh zest its light and elegant
tracery, its pleasant tone of colour, and the intricate
luxuriance of its wavy stems and branches. S. abietina
must be considered its nearest of kin, but the expression
of the two species is totally different ; the latter is coarse
and clumsy as compared with its graceful ally.

The reproductive capsules are rarely met with.

Hub. S. filicula must be accounted one of the more
local species, though it ranges from the north of Scotland
to Cornwall. In the south-west district it must be very
rare. Mr. Couch includes it in his ' Cornish Fauna/ but
I have never met with it amongst the large quantities of
trawl-refuse from Brixham and Plymouth which I have
examined from time to time, nor has it occurred to me in
the course of a lengthened and careful examination of the
Devon and Cornish coasts. It is common near Liverpool
and along the north eastern coast (Scarborough, Filey, &c.) .
Mr. Peach finds it " rather plentiful " at Peterhead, and

266 SERTULARIID^.

less so at Wick. Oban, in from 15-20 fath. (T. H.) : Nor-
folk and Suffolk (C. W. P.): Ireland (W. T.).

[Grand Manan, Bay of Fundy, in 20 fath., on shelly
bottoms (Stimpson): Labrador (A. S. Packard, jun.) .]

With alternate calycles.

5. S. ABIETINA, Linnseus.

" SEA-FIR," Ellis, Corall. 4, pi. i. figs, b, B.

SERTULARIA ABIETIXA, Linn. Syst. 1307; Pall. Elench. 133; Esper, Pflanz.

Sert. t. 1. figs. 1, 2; Lamk. An. s. V. (2nd ed.) ii. 141 ; Lamx.

Cor. flex. 189; Johnston, B. Z. 75, pi. xiii. fig. 1.
DYNAMENA ABIETINA, Flem. Br. An. 543.
LA SERTULAIRE SAPINETTE, Blainv. Actinol. 480, pi. 83. fig. G.
SEUTULARIA ABIETINULA, Dalyell, Anim. Scotl. i. 157, pi. xxv. figs. 6-13.

Plate LV.

STEMS thick, slightly flexuous, regularly pinnate ; branches
alternate, approximate, equidistant, simple or variously
ramified; HYDROTHEC^ comparatively large, croivded,
subalternate, swollen below, narrowed above into a short
neck, which is free and everted, with a plain, oblique
aperture; GONOTHEC^E subsessile, ovate, smooth, with an
even, shortly tubulous mouth.

S. ABIETINA sometimes attains a height of a foot, and in
luxuriant specimens is much and irregularly branched.
In this state it is one of the handsomest of the British
Sertulari(B. It is robust in habit and of a yellowish horn-
colour : the shoots are gregarious and closely packed to-
gether ; from a fragment of shell about f of an inch in
length by ^ an inch in width, I have seen as many as twenty
springing. In its young state it is simply pinnate ; but
mature and well-developed specimens exhibit a very luxu-
riant and striking ramification. The main stem, through
a large part of its course, is set with simple pinrise, which

SERTULARIA ABIETINA. 267

vary much in length, becoming gradually shorter towards
the apex. But every here and there branches are given off
of much larger size, which are themselves pinnate, or even
bi- and tripinnate, — copies, in fact, of the principal shoot.
These branches often curiously imitate the growth of the
parent stock, one or two only of their pinnae attaining an
exaggerated size and exhibiting a composite form. Some-
times a very large proportion of the pirmse on the main
stem are much elongated, continuing simple for about a
third of their length, and then becoming pinnate for the
remaining two-thirds. In this way very elegant specimens
are formed, which may remind us of the proliferous fronds
of some species of fern.

The capsules are produced in rows along the upperside
of the pinnae, and, it would seem, principally in the winter
and early spring. The ova are developed into planules
within an external marsupium, such as we find in Sertu-
larella polyzonias and other species. The embryos are of
a bright yellow colour.

The polypites, which project but little from the calycles,
have 26 (or more) short tentacles.

Hob. On shells, stones, &c. from deep water, very com-
mon ; generally distributed.

Amongst the refuse of the Brixham trawl-boats this
species occurs in immense quantity. The nets come up
laden with it and its allies S. argent ea and H. falcata, — a
glorious sight to the naturalist. The trawlers carry on
their work chiefly in about 30 fathoms, and at this depth
whole tracts of the sea-bottom must be clothed with a
luxuriant growth of these elegant corallines. Mr. Peach
informs me that at Durness, in Sutherland, S. abietina is
often thrown ashore, with a very small admixture of other
rejectamenta, by cart-loads, and is used as manure by the
Highlanders.

268 SERTULARIID^.

We shall feel no surprise at the quantity in which this
zoophyte occurs, when we remember that, besides the rapid
and prolific development of new shoots from the creeping
stolon, the planulse are produced in immense numbers.
At certain seasons the reproductive capsules cover the
pinnse in almost continuous rows, each of them containing,
according to Sir John Dalyell, a brood of six or seven
embryos. A finely grown specimen will bear some 500
pinnae, and if only a fourth of them should produce cap-
sules, and no more than six should occur on each of the 125,
we should have at the lowest computation 4500 planulse as
the offspring of a single shoot, and 90,000 of such a cluster
of shoots as I have described above. In the case of S.
aryentea the capsules are much more numerous, and we
may fairly reckon the produce of a shoot at 1 5,000 embryos.

[Belgium (Van Ben.): La Charente inferieure, common
(Beltremieux) : North Cape, abundant, where there is a
strong stream (Sars): Greenland (Fabricius): Mingan
Islands, Gulf of St. Lawrence, and Labrador (A. S. Pac-
kard, jun.) : St. George's Bank, Newfoundland (Stimpsou) :
Mediterranean (teste Pallas).]

6. S. AROENTEA, Ellis and Solander.

"SQUIRREL'S TAIL," Ellis, Corall. 6, pi. ii.figs. c, C.
SERTULARIA CUPRBSSINA fi, Linn. Syst. 1308.

,, CUPBESSINA (in part), Pallets, Elencb. 142 ; Esper, Pflanz. Sert.

t. iii. figs. 1, 2.

„ ARGENTEA, Ellis Sf Soland. Zooph. 38 ; Esper, Pflanz. Sert. t. xxvii.

figs. 1, 2 ; Lamk. An. s. V. (2nd ed.) ii. 143 ; Lamx. Cor. flex.
192 ; Johnst. B. Z. 70, pi. xv. and pi. xiv. figs. 3, 3 ; Agassi;,
N. H. U. S. iv. 35G.

„ FASTIGIATA, Fabricius, Faun. Groenlandica, 458,

DYNAMENA ARGENTEA, Flem. Br. An. 544.

Plate LVI.

SHOOTS gregarious, bushy, somewhat blunt at the top;

SERTULA1UA ARGENTEA. 269

STEMS slightly waved, of a dark horn-colour, subspirally
branched; branches alternate, approximate, tiro to each
internode, panicled, dichotomously divided and subdivided,
so as to form somewhat broad fan-shaped offshoots,
springing from different sides of the stem, in such a
manner that four or five constitute a whorl ; HYDRO-
THEC.E subalternate, short, urceolate, narrowed toivards
the upper part, which is free and divergent, and produced
into an acute point at the outer side, aperture small
and oblique; GONOTHEC.E broad at the top, attenuated
downwards, with two spines above, or sometimes only
one, and a slightly raised, circular apertiire.

ELLIS'S expressive name for this species, " the Squirrel's
tail," gives a better idea of its general aspect than any
technical description. The stems are thickly clothed with
branches to the very bottom ; but for some distance below
they are small, and they also diminish towards the apex,
the intermediate region being occupied by panicles of about
equal size, so arranged as to cover the stem completely
and produce the rotund and bushy appearance which is
characteristic of the species. The branches divide and
subdivide dichotomously ; and at certain seasons the pin-
nules thus formed bear the capsules, profusely, in rows.

In its young state S. argentea is simply pinnate, and
the pinnae all lie in the same plane ; but the branches soon
begin to divide and assume the corkscrew arrangement.

The shoots attain the height of a foot or more, and are
occasionally bifid ; they grow in dense clusters.

Hab. On shells, stones, &c. chiefly from deep water;
generally distributed. One of the principal elements of
the trawl-refuse on the south-west coast. S. argentea also
occurs at times between tide-marks, but of small size.

[Ostend (Van Ben.): mouth of the Elbe (Kirchenpauer) :
Greenland (Fabr. and Morch) : North Cape in 30-50 fath.

270 SERTULARIID.E.

(Sars): Southern Labrador, Caribou Island, in 8 fath., not
common (A. S. Packard, jun.): Nova Scotia (Dawson):
Grand Manan, common in 4-6 fathoms, attached to stones
(Stimpson): Massachusetts Bay (Agassiz): South Africa
(Busk).]

7. S. CUPRESSINA, Linnaeus.

" SEA-CYPRESS," Ellis, Corall. 7, pi. iii. figs, a, A.

SERTULARIA CUPRESSINA, Linn. Syst. 1308 ; (in part) Pallas, Elench. 142 ;

Lamk. An. s. V. (2nd ed.) ii. 144; Lamx. Cor. flex. 192 ;

Johnst. B. Z. 80, pi. xvi.
DYNAMENA CUPRESSINA, Flem, Br. An. 543.
SERTULARIA ARGENTEA, Dalyell, An. Scotl. i. 189, pi. xxxvii.

Plate LVII.

SHOOTS long and slender, tapering off very gradually towards
the apex, which is much produced ; STEMS stout and
straight, branched ; branches alternate, fan-shaped, nar-
row, rather distant, somewhat spirally arranged, dicho-
tomously divided, the pinnules long and few in number ;
HYDROTHEC^E subalternate, tubular, pellucid, adherent
through most of their length, and scarcely divergent
above, aperture wide, bilabiate, rising into a point on
each side; GONOTHEC.E elongate, tapering below, with
a sharp spine above at each side, or sometimes at
one only, and a central aperture slightly raised and
margin ate.

THE difference in habit between this and the preceding
species is so strongly marked, that each of them may be
recognized at a glance. Pallas, indeed, regarded them as
identical, but he seems to have formed a very imperfect
conception of the sum total of the distinctive characters.
Dr. Johnston confesses himself doubtful ; but Ellis seized
the main points of difference with characteristic quickness,
and saw their true value. His name for the present species,

SERTULARIA CUPRESSINA. 271

" the Sea-cypress" is very expressive of the peculiarities in
its mode of growth and the gracefulness of its habit.

S. cupressina is much larger than its ally, with a thicker
main stem and longer and much narrower branches, which
are less frequently subdivided and less crowded together.
They are gracefully arched or drooping, and of a delicate
pearly whiteness, offering a striking contrast to the stout
and deep-coloured and very conspicuous stem from which
they spring. The branches of S. argentea, on the con-
trary, are broad, compact, rigid, and dark- coloured, forming
a dense clothing, and giving a bushy appearance to the
shoot. Another salient feature of S. cupressina is its
much produced, spire-like apex. The branches begin to
decrease in size at a considerable distance below the top,
and from this point the shoot rapidly tapers away, often
running out into a bare and branchless extremity. The
calycles of the two species are also sufficiently distinct in
form. Those of the cupressina are appressed, tubular, not
much narrowed or divergent above, with a bilabiate mouth ;
while those of argentea are shorter, swollen below, tapering
upwards, with the aperture bent, sharply pointed at one
side, and oblique.

There are commonly six calycles to an internode in this
species ; but the number varies.

The polypites have about 20 tentacles, are long and
slender, and extend very far beyond the orifice of the
calycles.

The capsules, which when mature are crowned by their
large marsupial sacs, are produced in rows along the upper-
side of the pinnules, that seem to bend beneath their
load. They contain about six planules.

Hab. This species seems to be less abundant than the
preceding, though very widely distributed in deep water.
South Devon and Cornwall (T. H.): Dorset (Forbes): very

272 SERTULARIID^.

common along the Yorkshire, Durham, and Northumber-
land coasts ; of large size (2 feet long) at Peterhead and
Wick ; Norfolk (C. W. P.) : in the Bristol Channel (A.
M. N.) : various points on the Irish coast.

[Ostend, very abundant, not far from the shore (Van
Ben.): mouth of the Elbe, 2 feet in length (Kirchenpauer) :
La Charente inferieure, pretty common (Beltremieux):
Henley Harbour, Labrador, in 7 fath. (A. S. Packard,
jun.): Massachusetts Bay (Agassiz).]

8. S. FUSCA, Johnston.

SERTULARIA NIGRA, Jameson, Wern. Mem. i. 565; Johnst. B. Z. (1st eel.) 128.

DYNAMENA NIGRA, Flem. Br. An. 545.

SERTULARIA FUSCA, Joknsf. B. Z. (2nd ed.) 70; woodcuts, 57. fig. 6, 69. fig.

10 c, 70. fig. 11.

NIGELLASTRUM FuscuM, Gray, Cat. Br. Mus. Radiate, 75.
DIPHASIA FUSCA, Affass. N. H. U. S. iv. 355.

Plate L. fig. 2.

SHOOTS rigid, pinnate, lanceolate, very sparingly branched,
of a blackish-brown colour, highly varnished; STEM
rather stout, lined longitudinally, jointed at distant
intervals, with a row of alternate calycles on each side ;
pinnae alternate, several springing from each internode
of the stem, simple, attenuated at the base ; HYDROTHEC^E
closely set, and bent alternately to opposite sides, so as to
give a quadrangular appearance to the pinna, very small,
adnate, with a ivide oblong mouth; GONOTHEC^E pear-
shaped, subpedicellate, smooth, borne on the upperside
of the pinnae.

Height of well-grown specimens about 3 inches.

THE calycles in this species are truly biserial, but they
bend alternately in opposite directions, forming a zigzag
line, and have much the appearance of being arranged in
four rows. They are crowded and completely adnate.

HYDEALLMANIA FALCATA. 273

Hob. On stones &c. from deep water, rare ; this is an
exclusively northern form. Coast of Aberdeenshire (R.
Brown): Northumberland, at Dunstanborough (R. Em-
bleton): Cullercoats, and from the five-men boats (J. A.):
Whitburn, Durham (Miss M. Dale) : off Holy Island (New-
castle Dreclging-Committee) : Stonehaven (Lady Keith
Murray) : off Staples in 35 fath., and off Buchanness
(Lieut. Thomas): Peterhead, very fine, but not common
(C. W. P.): Scarborough (W. B.): Filey (T. H.).

Genus HYDRALLMANIA*, Hincks.

Der. Named in honour of Prof. Allman.

GENERIC CHARACTER. — Zoojjhytefjlant-like; stem bearing
plumous branches, jointed, rooted by a filiform stolon ; hy-
drotheca unilateral, arranged in distinct companies, each of
which occupies an internode ; gonothecas scattered, with a
simple, inoperculate aperture.

H. FALCATA, the type of this genus, was referred to Plu-
mularia by Johnston, on account of the unilateral arrange-
ment of the calycles ; but its affinities are with the Sertu-
lariidse, and not with the Plumulariidse : from the latter
group it is separated by the absence of nematophores.

H. FALCATA, Linnseus.

" SICKLE CORALLINE," Ellis, Corall. 12, pi. vii. figs, a, A, and pi. xxxviii. fig. G.
SERTULARIA FALCATA, Linn. Syst. 1309; Pall. Elench. 144; Esper, Pflanz.

Sert. t. ii. figs. 1, 2.
AGLAOPHKNIA FALCATA, Lamx. Cor. flex. 174.

* I ha-ve adopted this form for the generic name, simply because Allmania
has been already appropriated to a genus of plants, in honour of another
naturalist.

274 SERTULARIIDJE.

PLUMULARIA FALCATA, Lamk. An. s. V. (2nd ed.) ii. 160 ; Johnst. B. Z. 90,

pi. xxi. figs. 1, 2; Dalyett, An. Scotl. i. 17fi, pi. xxxiii.
PENNARIA FALCATA, OJcen, Lehrb. Nat. 94.

Plate LVIII.

STEMS slender, flexuous, spirally twisted, destitute of caly-
cles; branches alternate, rather distant, regularly pin-
nate and plumose, given off above each joint, — pinnae
alternate, jointed; HYDROTHEC^E tubulous, closely ap-
pressed one to the other, ranged in pectinated rows
along the pinnse, with a break at each joint, aperture
plain and obliquely truncate ; GONOTHEOE ovate, tapering
below, with a slightly tubular neck.

WHEN finely grown this species attains a height of 12
inches or upwards ; and the shoots are often compound,
dividing, especially towards the bottom, and bearing seve-
ral offshoots. The form is singularly elegant, from the
spiral disposition of the spreading plume-like branches
around the flexuous stem*. The pinnse are jointed at
regular intervals ; and each internode bears a company of
calycles, Avhich lean, as it were, one upon another, the
sharp outer angles of the oblique apertures giving a pecti-
nated appearance to the rows ; they occur on the branches
as well as the pinnse, but are not present on the main stem.
The polypites are minute and pure white.

The capsules are produced abundantly in spring, and
when filled with their yellow ova or planules " resemble so
many minute lemons both in shape and colour ." Their
structure is simple. A single sporosac, supported on a
short peduncle, fills a large portion of the cavity; and within
this (in the female) a number of light-yellow ciliated
embryos are matured, which escape at once through the
terminal aperture without passing through any marsupial

* " A series of feathers implanted in spiral arrangement around a slender
stem."— Sir J. Daly ell

THUIARIA THUJA. 275

stage. On fixing themselves, they assume the usual circular
form ; the stem soon begins to rise in the centre of the disk,
and the marginal portion is broken up into a number of
rays, which, like so many root-fibres, bind the shoot to its
place. These may still be traced in the adult condition.

In the young state the calycles are bent alternately in
opposite directions; but there is no departure from the
strictly unilateral arrangement (Plate LVIII. fig. c}.

When dried, the branches of H.falcata become recurved,
and assume the sickle-like appearance from which the
specific name is derived.

Hob. On shells and stones, in the coralline zone, uni-
versally distributed.

[Ostend, extremely common (Van Ben.) : Mingan Island,
Gulf of St. Lawrence (teste A. S. Packard, jun.): Grand
Manan; taken often in 35 fath. on the Hake-ground
(Stimpson): Massachusetts Bay (Agass.): South Africa
(Busk).]

Genus THUIARIA, Fleming.

Der. from 9 via, a cedar.

GENERIC CHARACTER. — Zoophyte plant-like ; stem branch-
ing, jointed, rooted by a filiform stolon ; hydrotheccs bise-
rial, imbedded in the substance of the stem and branches.

THUIAXIA is most closely allied to Sertularia ; but the ap-
pression and partial immersion of the calycles give it a pe-
culiar and very distinctive aspect. Few species are known.

1. T. THUJA, Linnaeus.

" BOTTLE-BRUSH CORALLINE," Ellis, Corall. 10, pi. T. figs, b, B.
SERTULARIA THUJA, Linn. Syst. 1308; Pallas, Elench. 140; Esper, Pflanz.

Sert. t. xxii. figs. 1-3 ; Lama-. Cor. flex. 193.
CET/LARIA THUIA, Lamb. An. a. Vert. (2nd ed.) ii. \Ki.

T2

276 SERTULAIIIID.E.

NIGELLASTRUM THUJA, OJcen, Lekrb. Nat. 93.

THUIARIA THUIA, Flem. Brit. An. 54.3; Johnst. Br. Z. 83, pi. xrii. & xviii.

figs. 1, 2.
BISERIARIA THUIA, Bluinv. Actinol. 482, pi. Ixxxi. fig. 3.

Plate LIX.

STEM filiform, rigid, zigzag (the spaces between the
angles very short) , ammlated towards the base, and
obliquely jointed for some way above it, black or dark
horn-colour and glossy, clothed with branches towards
the top, but in the adult state denuded of them through
the greater portion of its length; branches alternate,
somewhat spirally arranged (four forming a whorl) Jointed
to small projections (which remain after they have fallen,
and give a knotted appearance to the stem) , divided and
subdivided dichotomously ; branchlets rounded and taper-
ing towards the extremity ; HYDROTHEOE subalternate,
smooth, approximate, broadly ovate below, tapering
upwards, — the aperture transversely oblong, somewhat
arched above ; GONOTHEC^E produced at the base of the
calycles, subpedicellate, pear-shaped, smooth, with a
circular, slightly margiuated and operculate aperture.

THE fishermen's name for this species, " the Bottle-brush/5
which has been preserved by Ellis, gives an admirable idea
of its general appearance. The stems, which sometimes
attain the height of a foot, are bare for a great portion of
their length, the lower branches dying off as growth pro-
ceeds, while the upper, which remain attached, form a
cylindrical brush, of varying size, at the top ; they are
strongly annulated at the base, and spring from a dark,
spreading crust, concentrically wrinkled. Both Pallas and
Johnston describe the stem as being destitute of calycles
and joints ; but this is far from being the case. The lower
portion of it is divided into segments by strongly marked
oblique joints, which, however, do not extend upwards, or
at least only occur occasionally and without regularity ;

THTJIARIA ARTICULATA. 277

whilst a line of calycles winds round it spirally from top
to bottom. A single joint also occurs on the branches a
little above their origin ; and it is at this point that they
break off, leaving the basal portions, which form the knots
that roughen the denuded section of the stem.

The " brush " varies in size, and is sometimes of con-
siderable length. When fresh, it is of a fine reddish-brown
colour, and contrasts well with the dark shining stem.
The young is simply pinnate. The long, bare stalks of
Thuiaria thuja offer a fine field for settlers, and are com-
monly occupied by a large foreign population ; they are
often encrusted by CeUepora and Alcyonium, and over-
spread by the delicate network and minute cups of the
smaller Hydroida (Lafoea, Filellum, &c.) .

Hob. On shells &c. from deep water. A prevalent
northern form, ranging to the North Cape. The finest
specimens I have seen were from the Dogger Bank ; they
were remarkable for the great length both of the stem and
brush. South Devon (Turton and Kingston): Cornwall,
very rare ; from deep water, Polperro (Couch) .

[Mediterranean (taste Pallas): Tromso and North Cape
on shells (Pecten Islandicus &c.) in 30-40 fath. (Sars):
Gulf of St. Lawrence (tests A. Agassiz): a Thuiaria re-
sembling T. thuja is found, on the authority of Stimpson,
in Behring's Straits.]

2. T. AETICULATA, Pallas.

" SEA-SPLEENWORT or POLYPODY," Ellis, Cor. 11, pi. vi.

SERTULARIA ARTICULATA, Pallas, Elench. 137 ; Etper, Pflanz. Sei't. t. viii.

figs. 1,2.

,, LONCHITIS, Ellis # Soland. Zooph. 42.

CELLARIA LONCHITIS, Lamk. An. s. Vert. (2nd ed.) ii. 186.
TIIUIARIA ARTICULATA, Fletii. Br. An. 545 ; Johnst. B. Z. 84, pi. xviii. figs. 3, 4.
NIGELLASTRUM ARTicuLATUM, Oken, Lelirb. Nat. 93.

Plate LX.
SHOOTS simple or irreijulnrly divided; STEM very slightly

278 SERTULAttHD^E.

waved, compressed, annulated at the bottom, pinnate
above, generally naked below; pinna usually simple,
sometimes much divided and subdivided dichotoniously,
alternate or subalternate, attenuated at the base, approxi-
mate ; HYDROTHECJE subalternate, closely set, broad and
truncate below, becoming narrower above and projecting
slightly, with a plain, circular orifice ; GONOTHEC.E pear-
shaped, smooth, with a round aperture at the top and
an operculum.

ARTICULATA usually attains a height of from 4 to
6 inches. A very luxuriant specimen, dredged by Mr.
Hyndman off Sana Island (in forty fathoms), measured
10^ inches ; but this is quite an exceptional size. The
shoots are plumous in form, and, when living, of a "pellucid
amber-colour." They are commonly branched ; but there
is no regularity in the mode of growth. The pinnse are
usually alternate, but in some cases nearly opposite;
they are articulated, as in T. thuja, near the base to a
short projection from the stem, but are not deciduous to
the same extent as in that species. A row of calycles runs
up each side of the stem, two or three being placed between
every pair of pinnse.

A remarkable variety occurs in Shetland, of which I
have a specimen from Mr. Norman, which has the pinnse
much slenderer than in the common form, and the caly-
cles somewhat widely separated (Plate LX. fig. d). The
habit, too, is diffuse, and some of the pinnse are much
ramified.

Hab. Widely distributed, but not generally abundant;
on stones and shells from deep water. Cornwall, deep
water (50 fath.) (Couch): Devon, not uncommon (T. H.):
Scarborough (W. Bean): Northumberland (J. A.): Clyde
(Forbes): Norfolk, Peterhead, and Wick (C. W. P.): Sana
Island (Scotland) (Hyndman): Shetland (A. M. N.): Isle

PLUMULARIID^E. 279

of Man (Forbes) : Dublin (Ellis) : north of Ireland (W.
Thompson) .

Family IX. — Plumulariidae.

HYDROTHEC.E sessile and unilateral; ZOOPHYTE furnished
with nematophores (minute calycles, containing an
extensile offshoot from the ccenosarc, and frequently
bearing thread-cells}; POLYPITES with a single wreath
of filiform tentacles round a conical proboscis ; gono-
zooids always fixed.

ANTENNULARIA, Lamarck.

Der. From Antennula, dimin. of antenna, the feeler of an iiisect.
NEMERTESIA, Lamouroux.

GENERIC CHARACTER. — Zoophyte plant-like ; stems simple
or branching, jointed, clothed with verticillate branchlets,
and rooted by a mass of fibres ; hydrothecce cup-shaped ;
nematophores bithalamic, distributed along the stem ; go-
nothecce axillary, unilateral.

THE curious ^organs which Mr. Busk has named nema-
tophores make their appearance in the family of the
Plumulariidae, and are not met with beyond it. They
are present in great numbers on the members of this
genus ; but, as a full account of them is given in the In-
troduction, it is unnecessary to allude to them further in
this place.

280 PLTJMULARIID^.

1. A. ANTENNINA, Linnaeus.

"LOBSTER'S-EIORN CORALLINE Or SEA-BEARD," Ellis, Corall. 15, pi. ix. figS. U,

A, B.

SERTULARIA ANTENNINA. Linn. Syst. 1310; Pallas, Elench. 146; Esper,

Pflanz. Sert. t. xxiii. figs. 1-4.
NIGELLASTRUM ANTENNiNUM, Oken, Lelirb. Nat. 93.
NEMERTESIA ANTENNINA, Lamx. Cor. flex. 163.
ANTENNULARIA INDIVISA, Lamk. An. s. Vert. (2nd ed.) ii. 156.
„ ANTENNINA, Johnst. B. Z. 86, pi. xix. figs. 1, 3.

Plate LXI.

STEMS clustered, simple or slightly branched, elongate, erect,
filiform, and springing from a sponge-like mass of inter-
lacing fibres ; BRANCHLETS short, incurved, swollen at the
base — a whorl on each articulation of the stem — divided
by oblique joints into internodes, which are alternately
larger and smaller, the former bearing the calycles ; HY-
DROTHEOE small, campanulate, distant, with an even rim,
always separated by two joints ; NEMATOPHORES conical
cup-shaped, a pair almost immediately above each caly-
cle, and one below it — one on the small intervening in-
ternode, and two (one on each side) at the base of the
branchlet ; GONOTHEC^E produced singly in the axils of the
branchlets, oval, subpedicellate, with a subterminal cir-
cular aperture, looking towards the main stem.

•

THE long thread-like shoots of A. antennina grow in clus-
ters of as many as 40 or 50, and are inserted at the base
in a compact fibrous mass of considerable size, in which
fragments of shell, stones, &c. are usually imbedded. The
delicate chitinous threads or rootlets which compose this
curious appendage grow out in whorls from the lower
region of the stem, and represent the branchlets of the
iipper portion.

This species attains a height of 8 or 10 inches, and is

ANTENNULARIA ANTENNINA. 281

of a bright yellowish horn-colour when fresh. The
branchlets are supported on short processes from the main
stem, which are ranged in verticils, and are permanent.
The pinnules themselves are commonly broken off; and
specimens in this condition have much the appearance of
the lobster's antenna, whence the name is derived.

Allman has described a curious peculiarity in the struc-
ture of the ccenosarc, which is readily observed in speci-
mens preserved in fluid. " Instead of forming a single
tube, it consists of numerous separate tubules, each with
its ectoderm and endoderm. The tubules lie close upon
the polypary, and leave an unoccupied space in the axis
of the stem/' This peculiar structure gives a lined ap-
pearance to the stems.

The female capsule contains one sporosac (occasionally
two) , in which a single yellow ovum is produced ; and this
gives rise to a planuloid embryo of large size*.

In its earliest state the branchlets of A. antennina are
arranged alternately, and there is no tendency to the ver-
ticillate condition characteristic of the adult; in a more
advanced stage they form alternate pairs.

This species is sometimes slightly branched, but the
branching is of the simplest kind, amounting to nothing
more than an occasional bifurcation of the long slender
shoots.

Hob. Generally distributed in deeper water, and com-
monly on a sandy bottom.

[Belgium, common (Van Ben.): La Chareute inferieure,
pretty common (Beltremieux).]

* Sir J. Dalyell says that it is nearly one-twelfth of an inch in length.

282 PLTJMULAEJID^E.

2. A. RAMOSA, Lamarck.

" LOBSTER'S-HORN CORALLINE, var.," Ellis, Corall. 15, 16, pi. ix. figs, b, C.

SERTDLARIA ANTENNINA (3, Linn. Syst. 1310.

NEMERTESIA RAMOSA, Lamx. Cor. flex. 164.

ANTENNULARIA RAMOSA, Lank. An. s. Vert. (2nd ed.) ii. 156; Hassatt, Ann.

& Mag. N. H. vi. 168, pi. v. figs. 1,2; Johnst. B. Z. 88,

pi. xx.

SERTULARIA SETICORNIS, Hogg's Stockton, 33.
ANTENNULARIA ARBORESCENS, Hassall, Ann. N. N. xi. 111.

Plate LXII.

SHOOTS rising by a single trunk, which at a certain height
divides and subdivides irregularly, and springing from a
dense mass of root-fibres ; STEMS thick ; BRANCHLETS
long, tapering, slightly curved outwards, much swollen
at the base, jointed, the internodes straight and of
equal length, arranged in whorls, which are very closely
set, so that the stems are densely clothed with the hair-
like ranmles ; HYDROTHEC^; small, campanulate, distinct,
separated by a single joint; NEMATOPHORES the same in
number and arrangement as in the preceding species,
except that on the basal portion of the branchlets there
are sometimes as many as six, and one is present on the
main stem, a little above their origin ; GONOTHEC^E pear-
shaped, smooth, single, with a subterminal aperture,
facing towards the stem.

IT is not a little strange that there should have been so
much doubt and diversity of opinion amongst authors re-
specting the claims of this handsome form to specific rank.
Even the " lyncean Ellis " and Pallas were at fault ; and
Dr. Johnston, though he separates it from A. antennina in
his second edition, seems to have been thoroughly per-
plexed, and never to have arrived at a clear conviction on
the subject. Hassall, who rightly asserted the distinctness

ANTENNULARIA RAMOSA. 283

of A. ramosa, unwittingly increased the confusion by
basing his diagnosis mainly on a character which has no
real existence !

The distinctive points, however, are sufficiently marked
and are to be found not only in the ramification and
general habit, but also in the minute structure.

Mr. Alder was the first to indicate, and with his usual
accuracy, the differences in detail between the two species;
but even he has omitted one or two characters of consi-
derable importance. In general aspect A. ramosa and A.
antennina are strikingly dissimilar, the luxuriantly branched
and tree-like shoots of the former offering a decided contrast
to the long, simple, and thread-like stems of the latter.
But the difference is not due only to the ramification.
The stems of A. ramosa are much thicker than those of its
ally, and the whorls much more closely set upon them;
they are therefore more densely clothed with the branch-
lets ; and as these are longer than in A. antennina, and
more numerous in each verticil, they give a peculiarly
stout and rotund appearance to the shoots.

The ramuli are long and somewhat recurved, and have
none of the sickle-like shape which is characteristic of
those of the preceding species ; they are made up of
straight internodes of about equal length, each of which
bears a calycle. The short intervening internodes, sup-
porting a nematophore only, which occur in A. antennina,
are wanting; in A. ramosa the corresponding nemato-
phore occurs on the internode that bears the hydrotheca.

Had. Generally distributed ; as abundant as the prece-
ding. At Peterhead and Wick, Mr. Peach informs me, it
is commoner than A. antennina ; and so it is, according to
Macgillivray, at Aberdeen. It is very fine and abundant
in Shetland.

[South Africa (Busk).]

284 PLUMULARIID^E.

Genus AGLAOPHENIA, Lamouroux (in part).

PLUMULARIA, Lamarck (in part).
AGLAOPHENIA, M'Crady.

GENERIC CHARACTER. — Shoots plumose, simple or branched,
rooted by a filiform stolon ; hydrothecce cup-shaped or tu-
bulous ; nematophores only developed in connexion with the
hydrotheca, two lateral and one anterior; gonothecce col-
lected in corbulce, or borne singly near the base of the pinna.

FORBES long ago suggested the dismemberment of the
Lamarckian genus Plumularia. Johnston, taking the
hint, sketched a rearrangement in a note at the close of
his Hydroida, which very accurately represents the natu-
ral affinities, though he overlooked the character which
has the greatest value for the purposes of diagnosis.
More recently, Busk has proposed to divide Plumularia
into two generic groups, characterized by the disposition
of the nematophores and the presence or absence of a
corbula or protective case for the reproductive capsules.
Retaining the old designation for one of them, he has
suggested (but not published) the name Halicornaria for
the second.

There can be no doubt that the Plumularia; (omitting P.
falcata, Lamk.) divide themselves into two very natural
groups, based on the special arrangement of the nemato-
phores. In one section these organs are appendages of
the hydrotheca only, and are disposed on a very definite
and constant plan around it ; in the others they are
distributed generally and profusely along the stem and
branches. With this cardinal distinction are associated
differences of habit and aspect which give a marked fades
to the two genera.

AGLAOPHENIA. 285

The corbula, which is a pinna modified so as to form a
protective envelope for the gonothecse, is commonly pre-
sent in the former of these groups, but is by no means
universal. In one section, of which A. pennatula is the
British representative, it is altogether wanting. Where
it is present, it occurs under two forms. In A. pluma and
allied species it is a closed case; the transverse ribs or
girders which constitute the framework are united by a
thin chitiiious expansion, and the capsules are thus en-
closed in a pod-like receptacle.

In another section, to which A. myriophyUum and many
foreign species belong, the corbula is open ; a number of
disconnected curved processes, springing from the base
of the hydrothecee, arch over the capsules and afford them
a certain amount of shelter. These open corbulae are
often of great length, and are very beautiful structures.
In the second group of Plumularice the gonothecse are
always scattered and unprotected.

On the whole it seems better to retain the two old names,
assigning Lamouroux's to one division and Lamarck's to
the other, than to introduce a new term*.

The genus Aglaophenia is widely distributed, and con-
tains many very striking forms. Some of the species
attain a very large size. Dana describes the East-Indian
A. angulosa as reaching a height of 3 feet, and bearing its
plumes, on an average, about half an inch apart, on oppo-
site sides ; he computes that the number of polypites on
a single specimen is not less than eight millions, " all the
offspring of a single germ, and produced by successive
buddings."

* M'Crady and Agassiz have adopted this course.

286 PLTJMULARIID^E.

With closed corbulse.
1. A. PLUMA, Linnaeus.

"TiiE PODDED CORALLINE," Ellis, Corall. 13, pi. vii. figs, b, B.

SERTULARIA PLUMA, Linn. Syst. 1309; Pall. Blench. 149 ; Esper, Pflanz. Serf..

t. vii. figs. 1,2; Lister, Phil. Trans. 1834, 369, pi. viii. fig. 2.
AGLAOPHENIA PLUMA, Lamx. Cor. flex. 170 ; Agassis, N. H. U. S. iv. 358.
PLUMULARIA CRISTATA, Lamk. An. s. Vert. (2nd ed.) ii. 161 ; Johnst. B. Z.

92, pi. xxiii. figs. 1-3, and pi. xxiv. fig. 1.
„ PLUMA, Flem. Brit. An. 546.

PKNNARIA PLUMA, Oken, Lehrb. Natur. 94.

Plate LXIII. fig. 1.

STEM recurved, smooth, dark brown; pinnae alternate,
simple, one to each internode, approximate, springing
from the front of the stem; HYDROTHECJE cup-shaped,
expanding above, aperture patulous, with a strongly
denticulated and somewhat everted margin ; NEMATO-
PHORES tubular, channelled, the lateral small and not
projecting much ; the anterior stout, adnate through
great part of its length, free at the extremity, which
projects but slightly ; GONOTHEC^: oviform, protected by
a pod-shaped receptacle, formed by the union of a num-
ber of crested ribs, and occupying the place of a pinna.

Var. /3. Dichotomously branched, and of delicate habit.

I HAVE restored the original name conferred on this well-
known species by Linnaeus, which has been unaccountably
supplanted in later English works by Lamarck's designa-
tion.

The graceful plumes rise from a flexuous, creeping fibre,
which trails over the stems and branches of Fuci, and
especially of Halidrys siliquosa, large masses of which are
often profusely covered by this zoophyte. They sometimes
attain a height of 3 inches or upwards, and bear as many as
a dozen of the curious ribbed and crested cases (corbulce)

AGLAOPHENIA PLUMA. 287

which enclose the reproductive capsules. I have seen fine
Devonshire specimens in which the plumes measured
three-quarters of an inch across, and were most elegantly
curved.

The pinnae are of a lighter colour than the stem,, and
are set forward upon it, so that the pairs form a series of
obtuse angles ; and the plume is somewhat carinated below.
Each pinna is slightly arched, and the shoot itself is gene-
rally recurved; so that the whole structure is bounded
and pervaded by lines of beauty.

A variety (ft)* occurs, of very delicate habit, in which the
stem divides and subdivides dichotomously, each branch
being plumose and pinnate.

Hab. On weeds, especially Halidrys siliquosa, and occa-
sionally on shells, rocks, Sec. ; between tide-marks, and in
the Laminarian zone.

A. pluma is much more at home in the south and west
than in the north. We have no record of its occurrence
in Shetland, nor has Mr. Peach met with it at Peterhead
or Wick. Throughout the north it seems to be sparingly
distributed, whilst along the south-western coasts it is
extremely abundant and of great size and beauty. Be-
tween tide-marks it is of humbler growth, and is found
covering the surface of the rock, or investing the roots
and stems of Laminaria.

Westra, Orkney Islands (Lieut. Thomas) : Ayrshire,
often cast in after storms (D. L.): Whitburn Bay, North-
umberland (a single specimen found) (J. A.) : Filey, not
common (T. H.): Mersey, occasionally on Halidrys (Dr.
Collingwood) : Barmouth (J. Gr. Jeffreys): Isle of Man
(T. H.) : around the coast of Ireland (W. T.) : Dover
(Lister) : Jersey (A. M. N.) : Devon and Cornwall, very

* Var. dichotomn, Sars, Middelha vet's Litt. Fauna, 55.

288 PLTJMULARIID^E.

abundant ; Scilly (T. H.). Var. /3. Cork Bay (J. V. Thomp-
son) : Ilfracombe; South Devon (T. H.).

[Belgium, on Fucus, very rare (Van Ben.): La Charente
inferieure, pretty common (Beltremieux) : Bay of Naples,
not uncommon, growing on small algas, frequently on the
stems of Caulinia oceanica, of small size; also from 1-2
fathoms depth; Messina, from 30—40 fathoms, of much
larger size. Var. ft on Cystosira ericoides (Sars): Mossel
Bay, South Africa (Krauss) .]

2. A TUBULIFERA, Hincks.

PLUMULARIA CRISTATA, var., Couch, Corn. Faun. 32 ; Johns?, B. Z. 94, fig. 16.
„ TUBULIFERA, Hincks, Devon. Cat. Ann. N. H. (ser. 3) viii. 256,

pi. vii. figs. 1, 2.

Plate LXIII. fig. 2.

SHOOTS tall, slender in habit; STEM divided by oblique
joints into short internodes, each of which bears a
pinna; pinnae alternate, long, approximate, springing
from the anterior aspect of the stem; HYDROTHEC^E
deep cup-shaped, slender, incurved above in front,
margin finely denticulate, very slightly everted; NE-
MATOPHORES tubular, with an oblong terminal aper-
ture,— the lateral large and very prominent, forming
ear-like appendages on each side ; the anterior a long
spine-like process, tapering downwards, free through a
large part of its length, and sometimes projecting be-
yond the rim; CORBUL^ long, pod-shaped, with nume-
rous serrated ribs (7-11), which are very prominent and
sometimes rise at the top into crested ridges — furnished
with an expanded spur-like process with serrated edges,
springing from the base at one side ; GONOTHEC^E oval,
shortly stalked, arranged in a double row along the cen-
tral line.

THE plumes of this species are of a very delicate habit,
and reach the height of 2 or 3 inches ; they bear a strong

AGLAOPHENIA TUBULIFERA. 289

general resemblance to those of A, pluma, from which,
however, they are readily distinguished on examination.
The hydrothecae of A. tubulifera are slender, somewhat
elongate, gracefully incurved in front, with a very slightly
everted margin, and are not expanded above like those of
A. pluma, which are also broader and have a very patulous
opening. The marginal deuticulation is delicate, and very
much finer than in the latter species, in which the rim is
cut into large and prominent spines, that are much bent
outwards. The lateral nematophores, which in A. pluma
are small and inconspicuous, constitute a striking feature
in the present species, and give a peculiar aspect to the
pinnae when viewed in front. The anterior nematophore
in A. pluma is adnate throughout almost the whole of its
length, the extremity only being free, and this not pro-
jecting much. In A. tubulifera a considerable portion of
it is detached and very divergent, and it attains a much
greater size, sometimes rising above the rim.

A very curious and striking character of the present
species is the large spur-like process attached to the base
of the corbula. This is evidently a supernumerary rib,
which, instead of forming part of the protective case, is
converted into a mere appendage. The marginal teeth
which surround it, and also those which give the serrated
appearance to the ribs of the corbula, are all nematophores.

Hab. On seaweed, zoophytes, shells, &c. in moderately
deep water; not common. Off the Isle of Mull in 30
fathoms (Prof. E. Forbes): Cormvall, on Goryonia &c.
from deep water ; Oban Bay, abundant in 15 to 20 fathoms
(T. H.). Very fine and luxuriant specimens were obtained
in the last locality, in some of which the plumes were
bifid. Hebrides (A.M. N.).

[There is a specimen from Algoa Bay in Mr. Busk's
collection.]

u

290 PLTJMTJLARIID.T2.

With open corbulae.

3. A. MYRIOPHYLLUM, Linnseus.

" PIIEASANT'S-TAIL CORALLINE," Eflis, Corall. 14, pi. viii. figs. «, A.
SEIITULARIA MYRIOPIIYLLUM, Linn. Syst. 1309 ; Pall. Elench. 153 ; Esper,

Pflanz. Sert. t. v. figs. 1-3.
AGLAOPIIENIA MYRIOPHYLLUM, Lamx. Cor. flex. 168 ; Agassis, N. H. U. S.

iv. 358.
PLUMULARIA MYRIOPIIYLLUM, LamJc. An. s. Vert. (2nd ed.) ii. 159; Johnston,

B. Z. 99, pi. xxiii. figs. 4, 5 ; Landsborough, Pop. Hist. B. Z.

152, pi. ix. fig. 28.
PENNARIA MYRIOPHYLLUM, Oken, Lehrb. Natur. 94.

Plate LXIV. fig. 2.

SHOOTS clustered, tall, and "eminently plumous," of a
yellowish colour, rising from a tuft of tangled fibres;
STEM compound, gibbous, or swelling out at intervals
into oblong knobs, pinnate, single or slightly branched ;
pinnae alternate, set closely together, often of consider-
able length, springing from one of the tubes which com-
pose the stem, and so nearly in a single line as gene-
rally to fold together and appear unilateral; HYDRO-
THEC.E rather large, deep, cylindrical, margin very
slightly crenated, and rising into a single larger denticle
in front; NEMATOPHORES, two lateral, suberect, pro-
jecting a little above the rim, — one anterior, a curved
spinous process, with an orifice at the top, which em-
braces the lower portion of the calycle ; GONOTHEC^E
produced in pairs on modified pinnae near the base of
the hydrothecse, sessile, smooth, " resembling a mussel-
shell in shape," protected by a number of long, curved
processes denticulated on the outer edge, which arch
over them and form a kind of corbula.

THE stem of this very handsome species (the " Palma
marina" of old Barrelier*, the "PheasantVtail" of Ellis)

* 1714.

AGLAOPHENIA MYR1OPHYLLUM. 291

is formed of several tubes bound together, and exhibits one
or two peculiarities. On the back of it, " at nearly equal
distances, are formed little regular arch-like risings, which
are compressed and hollowed a little in the middle." (Ellis.)
This is a very accurate description of these curious promi-
nences, which have been supposed to mark the stages of
growth. They are formed by the occasional divergence of
a portion of the tubes from the ascending line of the stem,
and are, in fact, arrested branches. The ramification of
A. myriophyllum is very slight and simple, seldom passing
beyond a single division of the shoot, which generally takes
place not far from the bottom of it. In this way a double
plume is formed. The branch rises from one of the knobs,
and is a continuation of the divergent fascicle of tubes,
which in other cases remains a mere excrescence on the
stem. Frequently too, even when the branch is not per-
fected, the diverticulum rises into a free spinous point
above, which shows its real significance. I have seen a
small and imperfect plume springing from one of the
knobs on a branch, and it is possible that cases may occur
of still further ramification ; but the common habit of A.
myriophyllum is undoubtedly simple.

Another peculiarity of the stem is to be found in the
rows of closely set pores, with raised orifices, which occupy
the furrows between the tubes and give it a punctate
appearance under the lens.

The pinnae in perfect specimens usually clothe a large
proportion of the stem, a small section only towards the
base being naked.

The reproductive bodies, which were first noticed by Dr.
Landsborough, whose name is pleasantly associated with
this species, differ from those of its British congeners in
being protected by a number of detached overarching
processes, and not by a closed case or corbula. A. myrio-

292 PLVMUJLARIID^E.

phyllum attains a height of from 6 to 12 inches, and in
luxuriant specimens 18.

Hub. Rare, chiefly from deep water. Cornwall (not
common) (C. W. P.): Brixham, Torbay (occasionally
amongst the trawl-refuse) (T. H.) : Plymouth Sound
(Bellamy): Dartmouth (G. Busk): off Jersey, (Lewes) :
Mersey (Dr. Collingwood) : Embleton Bay, a single speci-
men (Dr. Embleton): Estuary of the Clyde (T. H.):
LamlashBay (D.L.): Aberdeen (Macgillivray) : LochFyne;
Shetland (A. M. N.): Peterhead, one specimen (C. W. P.):
Isle of Man (E. Forbes): Dublin, from very deep water
(Ellis): Belfast Lough (M'Calla): Youghal (Miss Ball).

[The Mediterranean (Pallas) : Massachusetts Bay (Agas-
siz): Mingan Islands, Gulf of St. Lawrence (teste A.
Agassiz).]

Without corbulse.

4. A. PENNATULA, Ellis and Solander.

SERTULARIA PENNATULA, Ellis Sf Soland. 56, pi. vii. figs. 1, 2.

AGLAOPIIEXIA PENNATULA, Lamx. Cor. flex. 168; Expos. Meth. ii. pi. vii.

figs. 1,2; Agassiz, TS. H. U. S. iv. 358.
PLUMULARIA PENNATULA, LamJc. An. s. Vert. (2nd ed.) ii. 165 ; Johnst. Br.

Zooph. 94, pi. xxii. figs. 1, 2.

Plate LXIII. fig. 3.

SHOOTS plume-like, slender, very graceful; STEM straight,
pinnate for about two-thirds of its length, naked below,
divided into short internodes, each of which bears a pair
of pinnse; pinnae subalternate, crowded, curved, and
springing from the anterior aspect of the stem ; HYDRO-
THEC<E small, cup-shaped, aperture wide, the margin
sinuated, ivith a minute denticle on each side, — a long
incurved spine springing from the base of each culycle
in front, rising considerably above the orifice and bend-

AGLAOPHENIA PENNATULA. 293

ing over it; NEMATOPHORES minute, one on each side
of the calycle above, placed a little below the margin,
and not projecting; GONOTHEC.E rudely pyriform, sub-
pedicellate, smooth, borne singly on the stem at the base
of the pinna.
Height from 3 to 6 inches.

THIS is a rare and beautiful species, of which Ellis might
well say that it is " as remarkable for its elegance of form
as its likeness to the feather of a pen." The pinnae are
placed very close to one another on the anterior surface
of the stem, and have therefore a tendency to fold together
and assume a secund appearance.

The most remarkable point in the history of this species
is the absence of the corbula, or protective case, which
encloses the gonothecse in other mem-
bers of the genus. The capsules, Fig. 33.
which have not been hitherto de-
scribed, are distributed along the
main stem, springing singly at the
base of the pinnae, just as in
other species they are produced at
the origin of the ribs which gird
the corbula (Woodcut, fig. 33). In
this case, the fertile plume itself

forms, as it were, a corbula, the pinnae arching over the
gonothecse. I have a variety from Devonshire which
measures three-quarters of an inch across, and is much
less delicate and feather-like than the ordinary form.

Hub. On shells, seaweed, &c. ; very rare. On the
Pinna ing ens, from deep water, off the Deadman point,
very rare (Couch) : obtained off the Cornish coast
several times on the Corwich crab and the stems of
Laminaria digit ata ; a magnificent mass from Gorran
Haven; Torbay, a single specimen (C.W. P.): Swanagc.

291 PLUMULAIUID^E.

Dorset, on Halidrys siliquosa; Teignmouth (T. H.) : near
lloundstonc, Gahvay (M'Calla) : profusely investing
about 6 inches of the stem of a Laminaria diyitata,
Youghal (Miss M. Ball). Miss Ball's remarkable speci-
men has supplied the principal cabinets in the country.

Genus PLUMULARIA, Lamarck (in part).

Der. Plumula, a little feather.

AGLAOPHENIA, Lamouroux (in part).
PLUMULARIA, M'Crady.
HAHCORNARIA, Busk, MS.

GENERIC CHARACTER. — Zoophyte consisting of plumous
shoots, simple or branched, jointed, attached by a creeping
stolon; hydrotheca cup-shaped; nematophores distributed
alone/ the stem and branches ; gonotheca scattered or
crowded together, but always unenclosed, differing in the
two sexes.

THE members of this genus are generally distinguished
by great delicacy of habit, and want the dense cor-
neous texture of the Aglaophenice. The nematophores,
which present two or three distinct forms, are usually de-
veloped in great profusion, and have no special connexion
with the calycles.

In some of the species the gonothecse are massed to-
gether in great numbers, in others they are distributed
singly ; but they are never gathered together in companies
under the protection of a corbula. They differ more or
less in the two sexes. The polypites are commonly shaped
like a dumb-bell, and of very large size in proportion to
the calycle, into which they are not wholly retractile.

PLUMULARIA PINNATA. 295

We know little of the geographical distribution of this
genus. It has representatives in North America; one or
two, at least, of our British species range to the Mediter-
ranean, and one has been found in Van Diemen's Land.
In the extreme north of Europe, both this and the pre-
ceding genus would seem to be sparingly developed, if not
altogether wanting ; for they are not recorded by Sars as
occurring in Norway, nor do they find a place in M orchis
list of Greenland Hydroids.

1. P. PINNATA, Linnaeus.

SERTULARIA PINNATA, Linn. Syst. 1312; Ellis $ Suland. Zoopk. 46.
AGLAOPHENIA PINNATA, Lamx. Cor. flex. 172.

PLUMULARIA PINNATA, Lamk. An. s. Vert. (2nd ed.) ii. 164 ; Johnst. B. Z. 95,
pi. xxi. figs. 4, 5 ; Agassis, N. H. U. S. iv. 358.

Plate LXV. fig. 1.

SHOOTS clustered, tall, white, or of a pale horn-colour ; STEM.
straight, jointed irregularly; pinnae alternate, several on
each internode ; HYDROTHEC^E rather distant, wide, with
an entire rim, separated by a sinyle, somewhat oblique
joint ; NEMATOPHORES sessile, very minute, one below each
calycle ; GONOTHEC^E forming a double row along the
main stem, rudely ovate or pear-shaped, shortly stalked,
and with a number of spinous projections at the top.

P. PINNATA sometimes attains a height of seven, and
commonly of four, inches; it also occurs of much
humbler gowth, rising only to one and a half inch or
two inches. It is distinguished from P. setacea by its
more robust habit and larger size, as well as its minute
structure. The calycles of P. pinnata are only separated
by a single joint, those of P. setacea by two. Several
pinnae usually spring from each segment of the main stem ;

296 PLUMULARIID^E.

but there is no constancy in the number ; and I have seen
specimens in which the internodes were short, as in P. se-
tacea*, and bore only one. Dr. Johnston assigned three
pinnse to each internode, and relied mainly on this cha-
racter as a distinctive mark of the species; but on the
same shoots the number often ranges from two to five. A.
much safer criterion is to be found in the nematophores,
which are scantily developed and exhibit a very peculiar
structure. They are not pedunculated as in the other
species, but consist of minute cup-shaped processes that
are immediately attached to the side of the pinna, one
below each calycle.

When present, the reproductive capsules afford another
good specific character; they are never axillary, but are
produced in rows along each side of the central stem.
They are irregular in shape, somewhat ovate, and generally
more or less spinous at the top. The male are smaller and
much less numerous than the female ; both sexes occur on
the same stem.

Hub. On shells, stones, seaweed, &c., from low-water
mark to deep water; common. It ranges from Cornwall
to Shetland, and is generally distributed. The deep-water
specimens are of the largest size.

2. P. SETACEA, ElllS.

"SEA- BRISTLES," Ellis, Corall. 19, pi. xi. figs, a, A.
COKALUNA SETACEA, EUis, Corall. pi. xxxviii. fig. 4.
SERTDLAUIA IMNNATA /3, Linn. Syst. 1312.
„ SETACEA, Pall. Elench. 148.

* It. must be remembered that in P. sctacca there is never more than one
pinna to an intcrnocle; the nilc in the case of P. pinnata is that there are
several.

PLUMULAEIA SETACEA. 297

AOLAOPHENIA SETACEA, LtttHX. Col", flex. '271.

PLUMULAIUA SETACEA, Lamk. An. s. Vert. (2nd cd.) ii. 165 ; Johnst. B. Z. 97,
pi. xxii. figs. 3-5 [not fig. 81, p. 465] ; Agassi;, N.H.U.S. 358.
PENNAIUA SETACEA, OJcen, Lekrb. Nat. 94.

Plate LXVI. fig. 1.

SHOOTS very delicate ; STEM slightly waved and regularly
jointed; pinna alternate, one to each internode, origina-
ting immediately below the joint, composed of longer and
shorter internodes, placed alternately, the former bearing
the calycles ; HYDROTHEC/E small, with an even rim, very
distant, separated by two joints ; NEMATOPHORES elongate,
two abreast behind and above the calycle, two in a line
beloiv it, one at the origin of the pinnae, and one on each
segment of the stem ; GONOTHEC^E borne in the axils of
the pinncs ; female ampnllate, smooth, produced above
into a tubular neck, with a plain orifice ; male linear-
oblong, slender, smaller than the female, less produced
above, and tapering to a fine point, with a very minute
terminal aperture.

P. SETACEA varies considerably in size; it is commonly
from an inch to an inch and a half in height, but some-
times attains a larger growth. A variety occurs which is
much and irregularly branched, and of luxuriant habit.
Its arborescent shoots are very unlike the neat little
plumes of the more usual form ; but the minute characters
of the two are identical. This variety, which I have only
received from Cornwall, I believe to be from deep water.
In rock-pools, and when fringing the stems and branches
of other zoophytes (it has a marked predilection for An-
tennularia], P. setacea is of extreme tenuity and delicacy.
In other situations it is frequently of robuster habit, the
main stems being stout and of a deep horn-colour.

This species is one of the commonest and prettiest of
the littoral Hydroids. Forests of its little plumes over-

298 PLUMULABinXE.

spread the surface of the rock in the tidal pools, or invest
the stems of the marine plants. So delicate is it, however,
that it is often difficult to detect — its faint shadow, cast by
the strong light of the summer clay on the rock from
which it springs, being often the only indication of its
presence to the collector*.

The capsules are produced in the axils only, and often
form a continuous row down the centre of the plume. The
difference of sex is less marked than in many cases. The
female capsule is of an elegant flask-like form, with a pro-
longed tubular neck terminating in an orifice sufficiently

* I recommend the following mode of proceeding to the hunter for minute
zoophytes. Of course, I assume that he is equipped in garments which the
old-clothesman would hardly covet, and that he is indifferent to appearances,
as he will probably be if he is a true naturalist. Let him select a likely pool,
one with overhanging ledges and clefts well draperied with weed, upon
which the sun may happen to be shining, and then let him lie down at full
length beside it, that he may be able to peer into it patiently and intensely,
without the fatigue and distraction of stooping. He must prepare for some
close and continuous looking — not merely running Ms eye over the bottom
and the rocky walls, but scanning them carefully inch by inch, raising the
curtain of hanging weed, and allowing the sunlight to pierce the chinks and
crannies and illuminate their hollows, coloured by the brilliant sponge or
the crust of the Lepralia, and teeming with varied life. He should bring
his eye to the edge of the pool, and look down the side, so as to catch the
outline of any zoophytes that may be attached to it amidst the tufts of
minute alga. He must not be content with a hasty glance, but look and
look again until his eye is familiar with the scene, and may accurately dis-
criminate its various elements. And let him watch for the shadows ; for in
following them he will often secure the reality. I have frequently detected
the tinyCampanularice and Plumulariae in this way, by means of the images of
their frail forms, which the light had sketched on the rock beneath them.
For tools, the hunter must have his stout, flat, sharp-edged collecting-knife,
a long-armed and substantial forceps, and a varied array of bottles, ranging
from the Homoeopathic tube to the pickle-jar. If his choice of ground be
good, and his patience proof, and his eye quick, he will have an ample
reward for his labour in the rich spoil of beauty which he will bear away,
even if he should not hit upon any novelty ; but amongst the minute
zoophytes there is still, I have no doubt, much to be done in the discovery
of new forms, as there certainly is in working out thoroughly the history of
those that are known.

PLUMULARIA CATHAR1NA.

299

Fig. 34.

wide to allow of the egress of the mature planulae ; the

ova are arranged in lines, and form a

compact mass, occupying the greater

part of the cavity. The male is smaller,

according to the general rule, and very

slender, wanting the long neck, and

with a minute orifice at the top*

(Woodcut, fig. 34, 0, male ; b, female) .

Hub. On weed, zoophytes, rock, &c.,
from the littoral zone to deep water;
generally distributed.

Branched var. Malahide (Macalla): Cornwall (T. H.).

[On Phallusia intestinalis, at Messina (Sars): Belgium,
on Laminaria (Van Ben.).]

3. P. CATHARINA, Johnston.

PLUMULARIA CATHARINA, Johnst. Mag. Nat. H. vi. 498, figs. 61, 62 ; Brit.

Zooph. 97, fig. 1 (p. 3), fig. 17 (p. 98) ; Agassiz, N. H. U. S.

iv. 358.

AGLAOPIIENIA CATHARINA, Gray, Cat. B. M. Radiata, 81.
?SERTULARIA SECUNDARIA, Cavolini, Pol. Mar. (German tr.) 105, pi. viii.

figs. 15, 16.

Plate LXVI. fig. 2.

SHOOTS clustered ; stems straight or slightly curved, deli-
cate, and pellucid ; pinna opposite, simple or pinnate,
the pairs distant ; HYDROTHECVE deep, with an even mar-
gin, separated by two joints, borne on the main stem as
well as on the pinna; NEMATOPHORES tapering doivn-
wards, expanding into a wide-mouthed cup above, — one
on each side of the calycles, pedunculated, and, two or

* Sir John Dalyell, by a curious blunder, has treated Plumularia setacea
as a portion of Antennularia ramosa, upon which he found it parasitic, and
regards the " ampullate vesicles " as a second kind of reproductive body be-
longing to the latter zoophyte (Rare and Rein. An. of Scotland, vol. i.
p. 205-9, pi. xxxix. figs. 9, 10).

300

three (sessile] in a line along the intervening internodes ;
many distributed over the main stem and creeping sto-
lon ; GONOTHEC^: springing from the base of the hydro-
thecse ; (male) elongate-ovate, slender, tapering above
and below; (female) pear-shaped, operculated, with a
two-jointed stalk, bearing two nematophores near the
base.

THE salient character by which this exquisite species may
be distinguished from all its British congeners is the
arrangement of the pinnse in exactly opposite pairs. This
gives it a very distinctive habit; and it has besides a
peculiar delicacy and beauty of its own. The pinnse slant
upwards ; they are also set forwards on the stem, and the
plumes have therefore the appearance of being partially
folded. A little above the point of origin a single joint
occurs ; and throughout the rest of the pinna the inter-
nodes which bear the calycles alternate with others on
which two or three sessile nematophores are ranged in a
line.

The lateral nematophores on the hydrothecae exhibit a
curious peculiarity : they are mounted on peduncles, by
which they are raised nearly to the level of the rim, and
are beautiful objects for examination with the microscope.
There is an extraordinary profusion of these curious organs
on this species, and they are present on the creeping
stolon as well as on almost every other portion of the
polypary.

The cup or bowl that surmounts the nematophores, and
contains the thread-cells imbedded in a granular mass, is
ample and patulous. I am not acquainted with any
zoophyte in which their structure can be studied to more
advantage.

The reproductive capsules bud from the portion of the
pinna or stem immediately below the hydrotheca, between

PLUMULAllIA CATHAKINA. 301

the base of the cup and the adjoining nematophore. The
male and female are dissimilar, and are intermingled not
only on the same shoot but on the very same pinna. The
female are relatively very ample. The oblique terminal
aperture is closed by an operculum, which is not cast off,
but remains attached at one point as by a hinge. The
central column bears a single sporosac, which
becomes terminal and occupies the upper Fig. 35.
portion of the cavity. One ovum, so far as
I have observed, is produced in each. In
the male, which is slender and comparatively
small, a mass of close granular matter, cor-
responding in shape with the capsule, extends
from the base to the top (Woodcut, fig. 35).

P. Catharina grows in dense clusters, and
attains a height of 3 or 4 inches.

A very curious and beautiful variety occurs in which the
erect stem is wanting, and simple shoots, exactly re-
sembling the pinnse of the ordinary form, are given off
directly from the creeping fibre. In this condition the
entire aspect of the zoophyte is so completely changed that
it might pass for another species. I have little doubt,
indeed, that the obscure Sertularia secundaria of Cavolini
is neither more nor less than the stemless form of P.
Catharina, or of some kindred species ; and the hydroid
described by Dana* under the name of Antennularia
cyathifera is evidently something of the same kind.

The creeping variety of P. Catharina is of a delicate
citron-colour when living ; it is found with reproductive
capsules.

This species was named by Dr. Johnston in honour of
his wife, to whom zoophytologists are under lasting obli-
gations for the drawings (many of them could hardly be
* United States Exploring Expedition : Zoophytes.

302 PLUMULARIID^.

surpassed in beauty) with which she enriched her husband's
classical work.

Hob. On shells, corallines, and especially the tests of
Ascidiaus, from deep water ; generally distributed. Abun-
dant and very fine in Shetland : Cornwall, plentiful ; I
have specimens overspreading the shells of Pinna from
60 fathoms : Arran Islands, west coast of Ireland (Barlee) :
Jersey (A. M. N.) : Peterhead and Wick, on the fisher-
men's lines (C. W. P.): Oban (T. H.): off Sana Island, in
40 fathoms (Hyndmau) : coasts of Yorkshire, Durham,
and Northumberland; Dublin Bay; Isle of Man (T. H.),
&c. &c.

The stemless variety I have dredged off Ilfracombe, and
found growing on Sertularella Gayi, from Cornwall :
Peterhead (C. W. P.).

4. P. ECHINULATA, Lamarck.

PLUMULARIA ECHINULATA, Lamk. An. s. V. (2nd ed.) 1G2; Johnst. B. Z. 464,

465, fig. 80.
SERTULARIA SETACEA, Lister, Phil. Trans, 1834, 371, pi. viii. fig. 4.

Plate LXV. fig. 2.

SHOOTS very delicate ; STEM curved, jointed, the inter-
nodes rather short and attenuated downwards, simply
pinnate ; pinnae alternate, arching gracefully, one on
each internode, with two joints immediately above the
point of origin; HYDROTHEC^E small and basin-shaped,
moderately distant, separated by a single joint ; NEMA-
TOPHORES very minute, cup-shaped, simple, adnate to
the side of the stem, one behind and above the calycle,
one below it, and one (or sometimes two] in the axils of
the pinna ; GONOTHEC^E ovate, subsessile, with longitu-
dinal spinous ribs, borne profusely on the creeping sto-
lon and the central stem.

P. ECHINULATA is commonly from | to 1 inch in height.

PLUMULARIA SIMILIS. 303

Its plumes arc very compact, slightly recurved, and some-
what wide. Dr. Johnston has exaggerated the amount of
resemblance between it and P. sctacea. Besides the dif-
ferences in size and habit, and in the form and position of
the capsules, there is a striking dissimilarity in the details
of structure, in the shape of the calycles, the jointing of
the stem and pinnse, and the number and character of the
nematophores. The latter in the present species are of
the simple type, whereas in P. setacea they are compound,
affording a very good illustration of the bithalamic form.
The female capsule encloses a single large sporosac, con-
taining many ova. The spinous processes, which form a
crest upon the longitudinal ridges f, vary in the degree of
development, and are sometimes of very considerable
length.

Hub. On stone and weed, between tide-marks and in
shallow water ; not uncommon. It shows a decided pre-
ference for Zostera marina and Chorda filum.

5. P. SIMILIS, Hincks.

PLUMULARIA SIMILIS, Hincks, Cat. Devon & Cornw. Zooph., Ann. N. H.

(ser. 3) viii. 257, pi. vii. figs. 3, 4.
„ SETACEA, Landsborough, Pop. Hist. B. Z. pi. ix. figs. 26, 2G*.

Plate LXV. fig. 3.

SHOOTS simple, slender, white, or of a pale horn-colour, and
attaining a height of about an inch and a half ; STEM
jointed, internodes long and of equal width throughout ;
pinnae alternate, one below each joint, set forward on
the stem; HYDROTHEC.E rather large, curving outwards
towards the top, entire, very distant, always separated
by two joints ; NEMATOPHORES minute, simple, one below
each calycle ; GONOTHECJE ovate, elongate, tapering below,

t "Vosiculis cristato-serratis." — Lamarck.

304 PLUMULARIIDyE.

subsessile, smooth, divided into seven or eight obscure
lobes, borne on the creeping stolon and the main stem.

THIS species is nearly allied to the preceding, from which,
however, it differs in size and general habit, as well as in
the minute characters.

The points in which it differs from P. echinulata are as
follows. The plumes are longer, narrower, and less com-
pact and graceful. The internodes of the stem are about
half as long again as those of P. echinulata, and are of
equal width throughout, while those of the latter species
taper a little below. The hydrothecae of P. similis are
rather large, curving gracefully outwards towards the rim,
and free above, with a wide circular opening, and are
very unlike the small basin-shaped calycle of its ally ;
they are always separated by two joints, while in echinulata
there is (normally) only one ; so that the cells are distant
in the one species, and comparatively crowded in the other.

In P. similis there is only a nematophore below the
calycles, none above them or in the axils as in P. echinu-
lata. And, lastly, the capsules are totally dissimilar.

Hob. South Devon, abundant on weed in the Lami-
iiarian zone; Isle of Man (T. H.): Donaghadee (G.
Hyndman): Dublin.

6. P. OBLIQUA, Saunders.

LAOMEDEA OBLIQUA, Saunders, in litt. ; Johnst. B. Z. 106, pi. xxviii. fig. 1.
CAMPANULARIA, Lister, Phil. Trans. 1834, 372, pi. viii. fig. 5.
PLUMULABIA OBLIQUA, HincJcs, Ann. N. H. (3rd. ser) viii. 258.

Plate LXVII. fig. 1.

SHOOTS minute, simple and very delicate; STEM flexuous,
jointed at regular intervals, pinnate ; pinnae given off at
each flexure, alternate, short, bearing a single calycle, and

PLTTMULAKIA OBLTQTJA.

305

with two joints a little above the point of origin ; HYDRO-
THEC^E campanulate, with a deeply sinuated rim ; NEMA-
TOPHORES minute, two immediately above and behind
the calycle, one below it, one in each axil and on each
internode of the stem; GONOTHEC.E very large, ovate,
truncate above.

THIS fairy-like species, which only attains a height of
about a quarter of an inch, was ranked by Dr. Johnston
amongst the Laomedece. It differs from its British con-
geners in having only a single calycle on each pinna, and
therefore wants the characteristic plumous form ; in all
other respects (in the presence of nematophores, which are
developed in great abundance, the structure of the stem,
and the character of the hydrothecse) it agrees with the
genus Plumularia.

The polypite has about sixteen very short arms.

The reproductive capsule was figured by Lister in his
remarkable paper in the ' Philosophical Transactions;' and
nothing, I believe, has been added to his
account of it. It is produced at the base
of the pinnae, contains a single sporosac
and is of remarkable size as compared
with the calycles (Woodcut, fig. 36) .

This minute species is rich in the elements
of beauty. The slender flexuous stem, the
graceful form of the hyaline calycle with its
sinuated rim, nestling in the curved arm of
the pinna, and the tenuity and transparency
of the whole render it a singularly attrac-
tive object.

Hab. On weed &c. near low-water mark,
observation has gone hitherto, P. obliqua must be accounted
a local species. It was originally discovered at Brighton,
and appears to be common in the south-eastern district.
It has occurred at a single point on the Cornish and South-

x

Fig. 36.

v*^, 553 .

: :•; j

m\

"• \

1

So far as

306 PLTTMULAUTtD.K.

Devon coasts ; and I have found it in abundance under the
ledges and in the pools near low-water mark on the Cap-
stone at Ilfracombe : here it forms miniature groves on
the sponge which coats the surface of the rock, or on the
roots and stems of weed. It is also extremely common on
the coast of Dorset, in Swanage Bay &c. Sidmouth, on
Rhytiphlcea (Miss Cutler) : Cornwall (Couch) .
[Van Diemen's Land.]

With compound stem.

7. P. HALECIOIDES, Alder.

PJ,UMUI,ARIA HAM:CIOIBE>I, Alder, Ann. N. H. (ser. 3) iii. 353, pi. 12.

Plate LXVII. fig. 2.

SHOOTS about an inch high, irregularly branched; STEM
compound throughout a great part of its length, simple
and very delicate towards the top, very slightly zigzagged ;
branches given off from different aspects of the stem, com-
pound towards the base, with three joints above the
point of origin; pinnce alternate, distant, springing im-
mediately below a joint, short, often bearing only a
single calycle, and never more than three or four ; HY-
DROTHEC.E very distant, separated by two, or rarely three
joints; NEMATOPHORES very minute, with a somewhat
oblique orifice, one above and one below each calycle, and
one on the central stern, above the origin of the pinna ;
ooNOTHECjE large, ovate, ribbed transversely, with a broad
truncated top, and a very short pedicel, borne on the
stem singly or in clusters.

THE branching of this singularly delicate and beautiful
species has a certain constancy in its irregularity. It is
almost always one-sided — a single branch, of preeminent
size, springing from one aspect of the stem (or sometimes
two or three) , while the opposite is almost bare. In its
mode of growth it is not unlike the genus Halecitim. The

PLTJMULARIA FUUTESCENS. 307

capsule resembles that of Clytia Johnstoni, and the form is
unique amongst the Plumulariidce.

The polypites have about 20 tentacles when mature.
Like others of their tribe they have the habit of throwing
the arms back and allowing them to droop gracefully round
the calycle.

Hab. On stones, and amongst sponge &c. covering the
surface of the rock, near low-water mark. Cullercoats,
and elsewhere on the Northumberland coast, not common
(J. A.): Roker, near Sunderlaiid (Mr. A. Hancock): Shet-
land (Barlee) : the Capstone, Ilfracombe, in the lower rock-
pools (T. H.). In the last-mentioned locality it is not at
all uncommon.

8. P. FRUTESCENS, Ellis & Soland.

SERTULARIA G-ORGONIA, Pall. Elencluis, 158.

„ FRUTESCENS, Ell is Sf Soland. 55, pi. vi. figs, u, A. and pi. ix.

figs. 1. 2.

AGLAOPHENIA FRUTESCEX.'?, Lama:. Cor. flex. 173.
PLUMULARIA FRUTESCENS, Lamk. An. s. Vert. (2nd ed.) ii. 1(50; Johnst. B. Z.

100, pi. xxiv. figs. 2, 3.
PENNARIA FKUTICANS, Okcn, Lehrb. Nat. 1)4.

Plate LXVIL fig. 3.

ZOOPHYTE irregularly branched, shrubby, of a black or dusky-
brown colour, varnished; STEM tapering, composed of many
delicate agglutinated tubes, the branches much and irre-
gularly divided and subdivided into pfumous shoots ; pinna
approximate, crowded, alternate, bearing a brancklet a
little above the point of origin, which is generally bifid ;
HYDROTHEC.E deep, almost cylindrical, adnate, with a
slightly everted plain margin, from one to three on each
internode; NEMATOPHORKS funnel-shaped, the terminal
cup wide and shallow, a pair behind and above the caly-
cle, and one below it ; GONOTHEC.E pear-shaped, shortly
stalked, obliquely truncate above, with a very large oper-
culated aperture, about three times the length of the
calycle.

x2

308

PLUMFLARIIDJE.

P. FRUTESCENS rises from a fibrous l)ase to a height of 5 or
(5 inches. The main stem divides into a number of
branched shoots, which give it a very bushy appearance.
A marked peculiarity is the line of bifid ramuli, which is
borne on the pinnse parallel with the central stem.

Hob. On stones and shells, in deep water ; rare. But
few habitats for P. frutescens have been recorded, though
it has a wide range. It is essentially a deep-water
zoophyte, and seems to be cast ashore in small quantity.
On the Yorkshire coast it is rare. It is occasionally
obtained amongst the immense masses of zoophyte which
a rough easterly gale flings on the sands at Filey ; and
Mr. Bean has dredged it at Scarborough. Mr. Alder
reports it rare off the coasts of Durham and Northum-
berland. Oban (T. H.): Stonehaven, Kincardineshire
(Lady Keith Murray) : Shetland, Middle Haaf ; Hebrides
(A.M.N.): Cornwall, not rare (Couch): South of Ireland.

[Algoa Bay (Krauss).]

Fig. 37.

Corbula of Aglaopheniu phima.

HYBRID JE. 309

Suborder III.— GYMNOCHROA.

HYIHUNA, Ehrenberg (in part), Corall. cles roth. Meer. 67 ; Johnston, 15.

121.

HYDKIIKE, Huxley, Oceanic Hydrozoa, 20.
GYMXOTOKA (in part), .T. V. Carus, Handb. d. Zoolog. ii. •">(>!!.

Family I. — Hydridae.
Genus HYDRA, Linnaeus.

])er. From uSpa, the name appropriated to the fabled Lcrmvun monster.

GENERIC CHARACTER. — Polypites locomotive, single, de-
stitute of polypary, cylindrical or subcylindrical, with a
single series of filiform tentacula round the mouth, and a
discoid adhesive base. Gonozooids always fixed, developed
in the body-walls.

THE body of the Hydra is composed of a gelatinous and
highly contractile substance, and is consequently liable to
many changes of form. The interior is occupied by an
ample cavity, which extends from one extremity to the
other, and terminates above in a simple orifice or mouth.
Around this are placed a variable number of contractile
tentacles arranged in a single wreath. The base of the
body expands into a kind of disk, by which the Hydra
attaches itself to the stems and leaves of plants, and by
means of which it can also glide slowly over their surface.
It fulfils the contrasted functions of attachment and
locomotion.

The tentacles are more or less extensile, and bear n
formidable armature in the shape of numerous thread-cells,
which arc grouped together on small prominences or

310 HYDRIDES.

nodules; they are admirable instruments both for the
capture and destruction of prey. Worms and larvae,
Entomostraca, and even minute fishes constitute the food
of the Hydra • and these are seized by the long, flexible
arms, and probably paralyzed by the threads which are
darted forth from the numerous batteries of thread-cells
covering their surface. It has been noticed that worms
which have escaped from the Hydra's grasp usually die
soon after, as if from the effects of some poisonous secre-
tion.

The Hydra, which is little more than a locomotive
stomach and feeding- apparatus, is remarkable for its
voracity and activity in capturing prey, seizing a worm
" with as much eagerness as a cat catches a mouse"*.

Like the rest of its tribe it is propagated in two ways,
by gemmation and by a true sexual reproduction. In
the earlier part of the year budding goes on rapidly, and
large numbers of young pullulate from various parts of the
body, which are developed into perfect polypites and
finally become detached. This vegetative process is
extremely productive : buds are often present on the
young Hydra before detachment; and as many as four
generations are sometimes organically united, so as to
form a composite being. " We have thus in a transient
stage of the life-history of the Hydra a representation of
that which is the permanent condition of most of the
hydroid zoophytes." Rarely, fissiparous reproduction
occurs, the fission being either longitudinal or transverse.

At certain seasons, and especially towards autumn,
true reproductive organs are developed, the spermary and
ovary being usually present on the same individual, but
borne on different regions of the body. The ovary is
a simple sac, formed by a bulging of the body-wall ; and

* B«kpr.

HYDRA.

311

Fig. 38.

between its investing membranes the ovum is developed
(Woodcut, fig. 38). After a time it bursts the ectodermal
covering which confines it, and
remains attached by a kind of
pedicel. At this stage a very
strong, elastic shell or capsule
forms round the ovum, the sur-
face of which is, in some cases,
studded with spine-like points, in
others tuberculated, the divisions
between the tubercles being polygo-
nal*. After a time the ovum drops
from its pedicel and becomes at-
tached by means of some mucous

secretion, in which state it remains until the liberation of
the embryo. The young Hydra, on issuing from the egg,
has four rudimentary tentacles (Woodcut,
fig. 39) . The ova are occasionally produced
in spring, and in this case they are hatched
in the course of the summer; but more
usually they are developed late in the
autumn, when gemmation has quite ceased,
and undergo no change till the following
year. The spermaries are developed as small
conical projections, a little below the base of the tentacles
(Woodcut, Fig. 40, a) .

The Hydra may also be multiplied indefinitely by me-
chanical division ; almost every portion, separated from the
rest, is capable of producing a perfect polypite. It has
even been observed to break up of itself into numerous
particles, which lived on for a considerable time, and at

* Vide a paper '• On the coexistence of ovigerous and spermatic capsules
on the same individuals of the Hf/clra viridi?'' by Prof. Allen Thomson
(Proe. Roy. Soc. Edinb. No. :J<>. 1*17 >.

Fig. 39.

HYDRIDJE.

last, in some cases, became encysted ; and it is not im-
probable that each of these fragments would ultimately
give origin to a polypite.

The affinities of the Hydridae are with the Athecata, and
Cams includes them in this group ; but the total absence
of polypary, the locomotive habit, and the character of the
reproductive organs seem to me to entitle them to rank
as a distinct suborder.

The Hydra are all inhabitants of fresh water. We know
little of the geographical distribution of the genus ; but it
occurs in North America as well as in Europe.

For a detailed history of the Hydra, and an account of
the curious experiments that have been made to test its
powers of reparation and endurance, reference may be
made to the classical 'Mernoire' of Trembley*, and to the
works of Baker t, KoselJ, Johnston §, Albany Hancock ||,
Laurent If, Jager**, and Eckerft-

1. H. VIRIDIS, Linnaeus.

POLYPES VERD.-S Trembley, Mem. 22, pi. i. fig. 1, pi. iii. figs. 1-10.
HYDRA VIRIDIS, Linn. Syst. 1320 ; Johnst. B. Z. 121, woodcut, fig. 28.
,, VIRIDISSIMA, Pallas, Elench. 31.

Woodcut, fig. 40.

POLYPITES grass-green; body becoming gradually more

* Mernoires pour servir a 1'histoire d'un genre de Polypes d'eau douce, a
bras en forme de cornes. 1744.

+ An Attempt towards a Natural History of the Polype. 1 743.

% Insektenbelustigungen, Tlieil iii.

§ History of Brit. Zooph. i. 125.

|| " Notes on a Species of Hydra found in the Northumberland lakes,'' Ann.
N. H. 1850.

^[ "Eecherches sur 1'hydre et 1'eponge d'eau douce," in Vaillant's 'Voy-
age de la Bonite.'

** " Ueber das spontane Zerfallen cler Siisswasserpolypen. &c.," Wien. Sitx.
1860.

++ Entwicklungsgeschichte des urunm Avmpolvpen ( Hi/dm rii-idix), ls,>->.

HYDRA VI1UDIS.

313

slender towards the lower extremity; tentacles (3-10,
shorter than the body.

THE ovaries are developed in spring and summer (April to

;^f

r

June or July), and also in the autumn. Ecker has re-
marked that the eggs produced in the early part of the
year run their course in the following summer, while those
produced in the autumn pass the winter without change.
The spermary and ovary are home on the same individual,
the former a little behind the tentacles, and the latter
towards the lower part of the body. In the present spe-
cies there seems to be usually only a single ovum.

H. viridis was discovered by Trembley in 1740.

Hab. Ponds and still waters ; very common.

314

HYDRI1XE.

2. H. VULGARIS, Pallas.

HYDRA VULGARIS, Pall. Elench. 30 ; Johnst. B. Z. 122, pi. xxix. fig. 2.
„ GRISEA, Linn. Syst. 1320.
,, BRUNNEA, Templeton, Mag. Nat. Hist. ix. 417, fig. 56.

Woodcut, fig. 41.

POLYPITES orange-brown • body cylindrical ; tentacula 7-
12, rather longer than the body.

THERE seems to be some variableness in the colour; a

Fig. 41.

bright red variety occurs occasionally, and Mr. Albany
Hancock has noticed a flesh-coloured variety in the North-
umberland lakes. The tentacles are rather numerous,
and have none of the remarkable extensibility which cha-
racterizes those of the following species.

The number of eggs produced by a single polypite at
once seems to range from four to seven.

Hab. Ponds and streams; common.

Var. rubra, Putney Heath, near London (J. E. Gray) :
ponds on Wimbledon Common (G. II. Lewes).

[The Hague (Trembley) .]

HYDIIA OLIGACTIS.

315

3. H. OLIGACTIS, Pallas.

"LONC;-ARMED FRESHWATER POLYPE," Ellis, Corall. 10, pi. xxviii. fig. C.
HYDRA OLIGACTIS, Fall. Blench. 29 ; Johnsf. B. Z. 124, woodcut, fig. 27.

,. FUSCA, Linn. Syst. 1320.

.. VERKUCOSA, Templeton, Mag. Nat, Hist. ix. 418, fig. 57.

Woodcut, fig. 42.

POLYPITES brownish ; the lower part of the body suddenly
attenuated, so as to form a kind of peduncle ; tentacula
6-8, capable of great extension, to several times as long as
the body.

THIS species is known at once by the sleuderness of the

Fig. 42.

inferior portion of the body, which has the appearance of

316 HYDKID^E.

a stem or pedicel. It is traversed by a narrow canal,
which terminates below, according to the observations of
Baker, in a small opening. The arms are comparatively
few in number, but are amazingly extensile.

This is a very beautiful and interesting species, and
apparently less common than the preceding.

Hab. Still waters ; rare : near London (Mantell) : near
Belfast (Templeton): the Avon, Guy's Cliff (T. H.).

4. H. ATTENUATA, Pallas.

HYDRA ATTENUATA, Pall. Elcncli. 32; Johnst. B. Z. 12.'3, pi. xxix. fig. I.
„ FALLENS, Turf., Gmel. iv. 692.

POLYPITES " light oil-green, the body attenuated below,
with pale tentacula longer than itself" (Dr. Johnston}.

H. ATTENUATA, according to Johnston, is larger than H.
vulgaris, and " of a more gracile form. Its colour is a dilute
olive-green, with paler tentacula, which are considerably
longer than the body, and hang like silken threads in the
water, waving to and fro without assuming the regular
circular disposition, which they commonly do in the H.
viridis"

I know nothing of this species. Fleming ranked it
under H. vulgaris ; but Johnston, after " long, continuous
observation of individuals in confinement," was convinced
of its distinctness.

Hab. Yetholm Lough, Roxburghshire (Johnston).

APPENDIX,

Family PodocorynidaB.

[Vide page 27.]

Genus PODOCORYNE, Sars (in part).

3. P. PROBOSCIDEA, 11. Sp.
Plate XXIII. fig. 4.

POLYPITES tall and rather stout, of an orange-brown colour,
with a very long and somewhat columnar, opake- white
proboscis, and about 14 tentacles, some of which are
tall and erect, and others short and borne at right angles
to the body ; GONOPHORES forming a large collar round
the polypite, at a short distance below the tentacles,
disposed in two rows, and borne on small tubercles,
ovate, red and purplish.

GONOZOOID. — In the specimens which I have examined, and
which were obtained in the month of September, the
gonozooids had all the appearance of being imperfectly
developed, and never became free. The umbrella and
the radiating canals were visible through the investing
capsule ; and round the free margin of the former were
eight short conical tentacles (four larger and four
smaller), bearing a patch of dark-brown colour near the
base. The cavity of the umbrella was occupied by an
orange mass, with the upper extremity always of a
purplish colour. This mass gradually increased in size,
and passed beyond the opening of the umbrella, but was
still enclosed by the ectotheca. The development was
not traced further ; but I have little doubt that this was

318 APPENDIX.

the spermary, and that the zoophyte was in the depau-
perated condition which marks the close of the breeding-
season"^. Earlier in the year the gonozooids would
probably become free., and mature their products after
liberation. In one instance, and in one only, the con-
tractile movement of the umbrella was observed.

P. PROBOSCIDEA is a larger species than P. carnea, and is
known at once by its long, cylindrical, and very conspicu-
ous proboscis, which is opake-white in colour, and has the
appearance of being fluted down the sides. The tentacles,
which are less numerous than in the last-mentioned species,
are ranged in two semialternating rows — one erect and of
considerable length, the other short, standing out from the
body, and placed a little behind the primary set. When
contracted they become very thick, and almost leaf-like
in form.

The gonophores are borne at a very short distance below
the tentacles, and form a double ring round the body.
They are supported on small tubercles, and sometimes
number nearly a dozen. There is no apparent difference
between the prolific and the barren polypites.

The exact nature of the adherent base was not deter-
mined ; but the polypary encircles the lower extremity of
the polypites.

Hab. On Laminaria-roots, and on stones in rock-pools,
Capstone, Ilfracombe.

Family Corynidffi

Genus CORYNE, Gaertner.

To the synonyms of this genus must be added the Haly-
botrys of Filippi. In a paper presented to the Royal
Academy of Turin, so recently as 1865, this author has
proposed the above name for a Mediterranean Hydroid,
which is nothing more or less than a very ordinary
member of the old and well-known genus Coryne.

Vide the ace-omit of Syncoryne ffravata, p. 54.

APPKMHX. 319

CORYNE PUSILLA, Gaci'tiier.

[ nth- pp. 39, 40.]

THE Stipula ramosa of Sars was referred with doubt to this
species before I had seen the figure of it in the ' Soedyrenes
Naturhistorie." After examining that figure I have no
hesitation in placing it amongst the synonyms of C.pusilla.
The male gonophores in this genus seem to be always
pointed above, while the females are spherical.

Genus SYNCORYNE, Ehrenb. (in part).
SYNCORYNE PULCHELLA.

. 57.]

Plate XV. fi. 3.

.

I HAVE obtained this species on Laminaria-roots from the
Capstone at Ilfracombe, and am thus enabled to give a
figure of it and to add some particulars to Prof. Allman's
description.

The polypites are long, of nearly equal width throughout,
with about 20 very short and thick tentacles, the capitula
of which are scarcely broader than the arm itself. Those
of the uppermost or oral verticil, consisting of four, are
much the largest, those of the lowest are only about one-
third the size. The stem tapers downwards.

There are three gonophores in each cluster, and some-
times two clusters on a polypite, sometimes only one.

SYNCORYNE FEROX, T. S. Wright.

CORYNK FEROX, Wright, Journ. Anat. and Physiol. i. 335.

STEMS single, smooth ; POLYPITES with thick, short tenta-
cles, having the capitula scarcely larger than the width
of the tentacle ; GONOPHORES borne beneath the tentacles.

GONOZOOID similar to that of S. decipiens.

A FULLER description were much to be desired.

This species is nearly allied to the S. decipiens, but

320 APPENDIX.

(lifters from it " in its more robust and clumsy habit."
The chief peculiarity lies in the tentacles, which are short
and nearly of equal thickness throughout ; " and though
they are surmounted by a cluster of thread-cells, the
thread-cells are so few in number that the tentacles can
scarcely be termed capitate."

The present species, according to Dr. Wright, is much
less hardy than S. decipiens. The latter will live for
several years in captivity, whereas S. ferox " seldom sur-
vives more than a few days after having been removed from
the sea." Dr. Wright does not give the number of ten-
tacles, nor does he tell us whether the gouophores are
clustered or not. It is not improbable that this species
may prove to be identical with the $. pulchella (Allman) .

Hob. Firth of Forth. " It inhabits, generally, crannies
in large shells tenanted by Hermit-crabs, and rarely the
hollows of stones found in pools at extreme low-water
mark" (T. S. W.).

Family Clavatellidse.

Genus CLAVATELLA, Hincks.

Prof. F. DE FILIPPI, of whose paper on Eleutheria I had
only seen a brief abstract when the account of this genus
was written, is very confident that one of the forms de-
scribed by Claparede under that name is specifically dis-
tinct from Clavatella prolifera. The mere variation in the
number of tentacles is not a point of any importance ; for
individuals agreeing in having six radiating canals have
been found with 8, 7, and 6 arms. But Claparede met
with specimens having only four radiating canals, and
Filippi says that this character is associated with a differ-
ence in general form and in some points of internal organi-
zation. If so, Claparede's zoophyte may be the sexual
zooid of another species ; but it would be satisfactory to
have the opportunity of examining the polypites before
coming to a decision. It is not a little remarkable that

APPENDIX.

321

the polypitcs of this family should have eluded the obser-
vation of so many excellent naturalists. Prof. Filippi tells
us that in his aquaria, towards the middle of April, the
free zooids of Clavatella prolifera were present " in numero
incalcolahile ; " yet he seems never to have traced them to
their stock.

The polypite is minute and exceedingly slender; but
when extended, its milk-white colour makes it easy to
detect in a good light. It is very limited in its habitat ;

Pig. 18.

Gronozooid of Clavafelln. with young budding.

and the small clean pools, on the higher rocks between
tide-marks, in which it delights are readily examined. It
is not a denizen of such as are thickly overgrown with
weed. Coralline, and a delicate bright-green alga which
grows in small tufts, constitute the chief vegetation of the
haunts of the Clavatella.

It loves the freshest and purest water, and, frail as it
seems and is, it is found amidst the tumultuous dash of the
waves on the most exposed portions of the coast. When
contracted, the body shrinks down amongst the algae, or

v

322

APPENDIX.

into some cranny in the rock,
and the arms are reduced to
mere knobs. (Woodcut, fig.
446).

It is difficult to understand
why Prof. Filippi applies the
name Eleutheria to the gono-
zooid of Clavatdla. He admits
that the latter is generically dis-
tinct from Quatrefages's zoo-
phyte, yet ranks it under his
name ! Eleutheria should be
restricted to the form described
by the French naturalist; the
species bearing arms with dis-
similar branches must be referred
to Clavatella.

Filippi has frequently seen
gemmation commencing on the
young zooid before its separation
from the parent, just as in Hy-
dra, so that three generations
were for the time organically
united. The number produced
by budding must be immense.
(Woodcut, fig. 43.)

Fig. 44.

Family Tubulariidse.
Genus TUBULARIA, Linnaus.

T. INDIVISA, Linnaeus.

I HAVE not included the T. calamaris of Van Beneden
amongst the synonyms of this species. The description of
it does not agree in some points with T. indivisa ; and Mr.
Alder, who had examined specimens supplied by Van

APPENDIX. 323

Beneden, felt doubtful as to the identity of the two. The
following is his note on T. calamaris (Van Ben.) : — " This
is not above half the usual size of T. indivisa, and of a
paler colour. It has rather the aspect of a different species;
but I should not like to decide without seeing something
further of it."

Genus CORYMORPHA, Sars.

C. NUTANS, Sars.
[ Vide p. 129.]

THE small specimen of Corymorpha obtained at Fowey
Mr. Alder regarded latterly as distinct from C. nutans.
He had also found a species at Douglas, Isle of Man,
which he thought might be the C. Sarsii of Steenstrup.
It is not improbable that the other Norwegian species will
be obtained on our shores.

Family Lafoeidse.

Genus FILELLUM, Hincks.

THE chitinous crust assigned to this genus is a very
doubtful character. In young specimens, and those which
are developed on shell, there is certainly no trace of any-
thing of the kind. Where the zoophyte spreads over the
stems of Sertularias, and the calycles are densely crowded
together, it has a spongy appearance ; but it is difficult to
say whether this is due to the presence of a " crust " or to
some other cause.

The Australian genus Lineolaria (Hincks), so far as the
polypary affords the means of judging, seems to be nearly
related to Filellum. It is furnished with spinous, re-
cumbent capsules.

324 APPENDIX.

Family Haleciidse.

Genus HALECIUM.

H. BEANII, Johnston.

ON Plate XLIV. fig. 3 an Halecium is represented which
was obtained by dredging off the Isle of Man, and which
I at one time considered a distinct species. I am now
inclined to regard it as only a peculiar condition of the
well-known H. Beanii. The capsules are for the most
part pyriform, but occasionally elongate, with a slight
depression at the summit. They are borne at the ex-
tremity of the lateral stem-processes, in the position
usually occupied by the calycles. In these particulars the
Isle-of-Man specimen differs from H. Beanii in its ordinary
condition ; and as it was thickly covered with the yellowish
pear-shaped capsules, it presented a very distinctive aspect.
The calycles, however, exhibited no peculiarities, and I
therefore merely direct attention to the variation in the
form and position of the reproductive bodies.

SUPPLEMENT TO APPENDIX.

Family Clavidae.

CORDYLOPHORA LACUSTRIS.

[ Fide page 16.]

I HAVE been favoured by Mr. W. Madeley, of Dudley,
with the following additional habitats for this species : —

On a piece of an old boat in the canal at Tipton ; on an
old boat in the Stourbridge canal, not far from Dudley,
plentiful.

SUPPLEMENT TO APPENDIX.

325

Family Corynidse.

Genus CORYNE, Gaertner.

Additional Species.

C. NUTANS, Allman.

Tn Norman's Shetland Dredging Report, Brit. Ass. Rep. 1868 (1869).

" TROPHOSO.ME. — HYDROCAULUS [stem] attaining a height
of about fonr lines, much branched ; branches subalter-
nately disposed, deeply and distinctly animlated, the
annulations of hydrocaulus [stem] becoming less dis-
tinctly marked towards the base ; POLYPITES depressed
on one side of the stalk, so as to assume a nutant posture,
ovate, with about 15 tentacles.

" GONOSOME unknown."

PROVISIONALLY referred to the genus Coryne in the ab-
sence of the gonozooids.

Hab. Shetland (Jeffreys and Norman).

Fig. 45.

I'lumidaria

LIST OE WOEKS ON THE HYDUOIDA.

ELLIS. Essay towards a Natural History of Corallines. 1755.
PALLAS. Elenchus Zoophytoram. 176G.

Amongst the older authors these two stand preeminent, — the
former for the closeness of his observation, and his sim-
ple truth to life both in his drawings and descriptions, the
latter for his admirably accurate and graphic diagnosis.

Ellis, following the lead of Peyssonel (1727), was mainly
instrumental in establishing the animal nature of the
Zoophytes.

CAVOLINI. Memorie per servire alia storia dei Polipi marini.
1785.

This work is replete with interesting observations.

LAMOTJBOTTX. Hist. Pol. flcxibles. 1816.

— . Exposition Methodique, <fcc. 1821.
LAJIAKCK. Animaux sans Yertebres, vol. ii. 1816.
LISTER. Philosophical Transactions for 1834.
SAIIS. Bidrag til Sordyrenes Naturhistorie. 1829.
— . Beskrivelser og Jagttagelser &c. 1835.
— . Eauna Littoralis Norvegiae, vol. i. 1846.
— . Bidrag til Kundskaben om Middelhavet's Littoral-Fauna.

1857.

— . " Ueber das Ammengeschlecht Corymorpha und seine
Arten," Archiv f. Naturgcschichte. I860. Translated in
Ann. N. H. for 1861, viii. p. 353.

. " Bemajrkninger over fire norsko Hydroidcr," Videnskabs

Forhandl. 1862.
LOVEN. " Bidrag till Kiinnedomen af Slagtena Campanularia och

Syncoryna," translated in Wiegrn. Archiv for 1837.
COUCH. Cornish Fauna. 1838.

VAX BENEDEN. " Mem. sur les Campanulaires de la cote
d'Ostende," 1843, Mem. de P Academic Royale tie Belgique,
vol. xvii.

— . " Me'moire sur les Tubulaires,'' lltid.
. Rech. sur la Faunc littorale de Bclg. Polypes. 1866.

328 LIST OF WORKS ON THE HYDRO IDA.

QUATEEFAGES, A. BE. " Mem. sur rEleutherie dichotome, nouveau.

genre de Rayonnes, voisin des Hydres," Ann. Sc. Nat. (2nd

ser.), Zool. vol. xviii. 1842.
— . " Mem. sur la Synhydre parasite," ibid. 1843, vol. xx.

p. 230.
DUJARDIN. " Observations sur mi nouveau genre de Medusaires

(Cladonema) provenant de la metamorphose des Syneoryn.es,"

Ibid. p. 370.
— . " Mcmoire sur le developpement des Medusaires et des

Polypes Hydraires," ibid. (3rd ser.) 1845, vol. iv. p. 257.
STEENSTRTJP. On the Alternation of Generations. Translated by

Busk for the Ray Soc. 1845.
DALYELL, Sir J. G. Rare and remarkable Animals of Scotland.

2 vols. 1847-48.
JOHNSTON. A History of the British Zoophytes (2nd edit.). 2

vols. 1847.
CARPENTER, W. B. " Review of the works of Dalyell and others,"

Brit. & For. Med. Chir. Review, vol. i. p. 183 : 1848.
FORBES. A monograph of the British naked-eyed Medusae. Pub-
lished by the Ray Soc. 1848.
MUMMERY. " On the development of Tubularia indivisa," Quart.

Journ. Micr. Sc. 1853.
GEGENBATJR. Zur Lehre vom Generationswechsel und der Fort-

pflanzung bei Medusen und Polypen. 1854.
. " Versuch eines Systemes der Medusen, &c." Zeitschr. f.

wiss. Zool. 1857, vol. viii. p. 202.
HINCKS, THOMAS. " Notes on the Reproduction of the Campanu-

lariadaj," Ann. N. H. (2nd ser.) Aug. 1852.
— . " Further Notes on British Zoophytes, with descriptions of

new species," ibid. March 1853.
— . " Notes on British Zoophytes, with descriptions of new

species," ibid. February 1855.
— . " On Clavatella and its Reproduction," ibid. February

1861.
. " A Catalogue of the Zoophytes of South Devon and South

Cornwall" (6 plates), ibid. 1861-62, and separate.
. " On the Production of similar Gonozooids by Hydroid

Polypes belonging to different genera," ibid. December 1862.
— . " On some new British Hydroids," ibid. January 1863.
— . " On new British Hydroida, ibid. (3rd ser.) xviii. p. 296.

LIST OF WORKS ON THE HYDROIDA. 329

ALLMAN. " On the Anatomy and Physiology of Cordylophora,"
Phil. Trans. 1853.

. " On tho Structure of the Reproductive Organs in certain

Hydroid Polypes," Proc. Roy. Soc. Edinb. Sess. 1857-58.
— . " Additional observations on the Morphology of the Repro-
ductive Organs in the Hydroid Polypes," ibid. Dec. 1858.
— . " Notes on the Hydroid Zoophytes," Ann. N. H. for July,

August, and November 1859.

. " Note on the Structure and Terminology of the Repro-
ductive System in the Corynidse and Sertulariadse," ibid. July
1860.

. " Notes on the Hydroid Zoophytes " (sexual zooid of Di-

coryne conferta, &c.), ibid. Aug. 1861.

. "Notes on the Hydroida" (structure of Gorymorpha

nutans, &c.), ibid. Jan. 1863.

. " Report on the present state of our knowledge of the

Reproductive System in the Hydroida," Report Brit. Assoc.
for 1863.

. " On the Occurrence of Amcebiform Protoplasm and the

Emission of Pseudopodia among the Hydroida," Ann. N. H.
for March 1864.
— . " On the Construction and Limitation of Genera among

the Hydroida," ibid. May 1864.

GOSSE. A Naturalist's Rambles on the Devonshire coast. 1853.
WRIGHT, T. STRETHILL. " On Hydractinia echinata," Edinb. N.

P. Journ. for April 1857.

— . " Observations on British Zoophytes," ibid. July 1857.
— . Ditto (Laomedea acuminata &c.), ibid. Jan. 1858.
— . Ditto (Stauridia producta &c.), ibid. April 1858.

. Ditto (Atractylis &c.), ibid. Jan. 1859.

— . Ditto (Coryne implexa &c.), ibid. July 1859.

. " Observations on British Protozoa and Zoophytes," Ann.

N. H. for Aug. 1861.

. " Observations on British Zoophytes " (reproduction of

jEqiiorea vitrina &c.), Micr. Journ., N.S., vol. iii.
— . Paper in Journal of Microscopical Science, N.S., vol. ii.
ALDER, J. " A Catalogue of the Zoophytes of Northumberland
and Durham," Trans. Tynes. Nat. F. Club, 1857.

. Supplement to the above, ibi<l. vol. v.

. " Description of two new Species of Scrtularian Zoophytes

330 LIST OF WORKS ON THE HYDROLDA.

found on the coast of Northumberland," Ann. N. H. (3rd

ser.) vol. iii. p. 353.
AIDER, J. Description of a Zoophyte and two Species of Echino-

dermata new to Britain," ibid. Feb. 1860.
M'CiUDY. " Gymnophthahnata of Charleston Harbour," Proc.

Elliott Soc. Charleston, 1859.
HUXLEY. " The oceanic Hydrozoa," with a general introduction.

Eay Soc. 1859.
HODGE, G. " Contributions to the marine Zoology of Seaham

Harbour," Trans. Tynes. F. C. vol. v. pt. ii. p. 78, 1861.
KROHN. " Beobachtungen iiber den Bau und die Fortpflanzung

der Eleuiheria, Quatref.," "Wiegm. Archiv, 1861.
AGASSIZ, L. Contributions to the Natural History of the United

States : Acalephte. Yols. iii. & iv. 1860-62.
AGASSIZ, A, " Mode of Development of the Marginal Tentacles

the free Medusae of some Hydroids," Proc. Bost. Soc. Nat.

Hist. vol. ix. p. 81 : 1862.

. Illustrated Catalogue of North American Acalephae. 1865.

GREENE, J. KEAY. Manual of the Subkingdom Ccelenterata. 1861.
KIRCHENPATJER. " Die Seetonnen der Elbmiin dung: ein Beitrag

zur Thier und Pflanzen Topographie," Abhandl. d. Naturh.

Vereins, iv. Hamburg, 1862.
— . Ueber neue Sertulariden, 1864.
CARTJS u. GERSTAECKER. Handbuch der Zoologie, vol. ii. pp. 543-

562: 1863.
CLAPAKEDE. Beobachtungen iiber Anatomie und Entwickelungs-

geschichte wirbelloser Thiere. Leipzig, 1863.

. Paper on Lizzia, Zeitsch. fur wissen. Zool. 1860, p. 401.

NORMAN, A. M. " On undescribed British Hydroida, Actinozoa,

and Polyzoa," Ann. N. H. for Jan. 1864.
MOBIUS, KARL. Ueber den Bau, den Mechanismus und die Ent-

wicklung der Nesselkapseln einiger Polypen und Quallen.

1866.

KOLLIKEE. Icones Histologies, part ii.

HEICHERT. " On the Contractile Substance and Intimate Struc-
ture of the Campanularioe, Sertularias, and Hydridce," Mo-

natsbericht der Akad. der Wissenschaften zu Berlin, July

1866; tr. in Ann. N. H. for Jan. 1867.

A list of works on the Hydridce is given in the account of
this family (p. 312).

331

LIST OF WOODCUTS IN THE INTRODUCTION.

No. Page

i. C.ilycle and polypite of Clytia .... T. H ix

ii. Thread-cell of Hydra After Mouirs. . xii

iii. Ditto of Caryophyllia Ditto . . xii

iv. Calycles of Diphasia, showing the ) T< TT

operculum |

v. Pedunculate nematophore T. H xvi

vi. Neuiatophores of Aglaophenia pluma After ALLMAM xviii

vii. Ditto of Phtmulariafnetescens T. H xviii

viii. Gonophore of Coryne After ALLMAN xxii

ix. Ditto of Aglaophenia pluma . . Ditto . . xxii

x. Fertile polypite of Podocoryne .... T. H xxiii

xi. Medusiform zooid T. H xxiv

xii. Tentacle of the same, with lithocyst T. II xxv

xiii. Free zooid of Podocoryne, after ]

the disappearance of the um- I T. H xxviii

brella j

xiv. Male capsule of Gonotliyrcea WYVILLE THOMSON xxxvi

xv. Female capsule of Campamilaria . . Ditto . . xxxviii

vvi. The planula of Campamilaria Ditto .. xxxix

xvii. Capsule of Sertularia, with exter- ) T> u .1-

nal marsupium (

LIST OF WOODCUTS IN THE WORK.

1. Section of the base of Hydractinia . . G. BUSK 21

2. Lar Sabellarum After GOSSE 35

3. Coryne vermicularis T. H 44

4. Coryne ViinBenedetiii. The embryo After VAN BENEDEN 46

5. Cladonema radiatum. Polypites in ) 77. -ITT TT u

different conditions ... j K W'H' H°LDSWORTH G4

(i. Male gonophore of Eudendrium .... T. H 79

7. Female ditto ditto T. H 80

8. Eudendrium rameum. [Frontispiece.] \ mm-r?

9. Perif/onimus bitenfaciilatus After T. S. WRIGHT 98

10. P. quadritentaculatus , ditto ditto 99

11. Bougainvillia, ? species After VAN BENEDEN 113

12. Vortidara, with young polypite bud-

ding from the stolon

13. Gonozooid of Podocoryne arcolaia. ... G. HODGE U5.5

14. Campanularia a>n/ulata WYVILI.E THOMSON !:!<;

332 LIST or WOODCUTS.

No. Page

15. Gonozooid of 1 • i A .>
Clytia bicophora. . I in dift'erent stages. After A. AGASSIZ

16. Ditto ditto 1

17. Calycle of Obelia gelatinosa T. H 152

18. Gonothecae of Campanularia Hincksii T. H 163

19. Caiycle of Lovenella clausa T. H 178

20. Gonozooid of Thaumantias inconspicua After FORBES .... 179

21. Tentacular web of Campanulina acu- I . «, m q WuraHT 188

minata j

22. Lizzia grata After A. AGASSIZ . . 197

23. Lafoea dumosa, var. robusta After SARS 201

24. Lafoea parvula TUFFEN WEST .... 204

25. Lafoea (Calycella) plicatilis After SARS ....... 208

26. Trichydra pudica After T. S. WRIGHT 217

27. Female capsule of Halecium labrosum T. H 226

28. Sertularella fusiformis and S. tenella. . J. ALDER 234

29. Gonotheca of Sertularella Gayi T. H 238

30. Ditto of S. triatxpidata T. H 240

31. Ditto (male) of Diphasiu fattiu T. H 250

32. Scrtularia pumila T. H 259

33. Gonotheca of Aglaophenia pennatula T. H 293

34. Male and female capsules of Pluinu- \ m TT Ooa

7 ? X, II _•'•'

lana setacea j

35. Male capsule of Plum. Catharina T. II 301

36. Gonotheca of Plum, obliqua T. II 305

37. Corbula of Aglaophenia pluma T. H 308

38. Ovum of Hydra viridis After ECKER 311

39. Embryo of H. viridis ... ditto 311

40. Hydra viridis, with spermary and) After ALLEN THOMSON 313

ovary f

41. Hydra vulgaris T. II 314

42. Hydra oligactis T. H 315

43. Clavatella prolifera. Gonozooid I A /., T. 09-1

1 • J" xillGl J. ILJi^Jrl tJ*. J.

bearing gemma j

44. a. Clavatella prolifera (polypite). I rr. TT QOO
, m i j.ij • j. -it, !• -tl oZZ

b. lentacles contracted into knobs. |

45. Plumularia setacea . . . T. II 325

ALPHABETICAL LIST OF WOODCUTS.

Aglaophenia pennatula. Gonotheca 293

A. pluma. The corbula 308

Bougainvillia, ? species 113

Cinnpanularia nngulata 136

LIST OP WOODCUTS. 333

Pago

Campamdaria Hincksii. Gonothecae 163

Campanulina acuminata. Tentacular web 188

( ladonema radiatum. Polypites in various attitudes 64

Clavatella prolifera. Gonozooid, with gemmae 321

C. prolifera. Polypite 322

Clytia bicophora. Gonozooid in different stages 142, 143

Coryne vermicularis 44

C. Van-Benedenii. The embryo 46

Diphasia fattax. Male capsules 250

Eudendrium. Male gonophore 79

„ Female „ 80

,, rameum Frontispiece

Hakcium labrosum. Female capsule 226

Hydra viridis. The ovum 311

„ „ The embryo 311

„ ,. "With spermary and ovary 313

„ vulgaris 314

„ oligactis , 315

Hydractinia. Section of the base 21

Lafoea dumosa, var. robusta 201

,, parvula 204

„ ( Catycelld) jilicatilis 208

Lar Sabellarum 35

Lizzia grata 197

Lovenella clausa. The calycle 178

Obelia gelatinosa. Ditto 152

Perigonimus bitcntaculatus 98

„ quadritentaculatus 99

Plumularia setacea 325

„ ,, Male and female capsules 299

„ Catharina. Male capsule 301

„ obliqua. Capsule 305

Podocoryne areolata. Gonozooid 135

Sertularetta fusiformis 234

„ temtta 234

,, Gayi. Gonotheca 238

„ tricuspidata. ,, 240

Sertularia pumila 259

Thaumantias inconspicua. Gonozooid 179

Trichydra pudica 217

Vorticlara. With young budding from the stolon 132

334

The following are the names indicated by the initials
given in the lists of habitats :—

A. H. H Arthur Hill Hassall.

A. M. N Alfred Merle Norman.

C. W. T. . Charles William Peach.

D. L David Landsborough.

G. H George Hodge.

G. J. A George James Allman.

J. A Joshua Alder.

J. G. J J. Gwyn Jeffreys.

T. H Thomas Hincks.

T. S. W Thomas Strethill Wright.

W. B William Bean.

W. T William Thompson.

ERRATA.

Introduction, page rxii, line 5 from the bottom. For Clava read Coryne.
Page 2, line 17 from the top. For Skagarack read Skager Rack.
Page 35, line 10 from the top. For Eudcndriida read Atractyliclce.

INDEX.

[Synonyms are in Italics.]

Page

ArilARADRIA 133

larynx 134

AfiLAOPHENIA 284

pluma 286

tubulifera 288

myriophyllum 290

pennatula 292

Amphisbetia 259

Amphitrocha 234

ANTENNULARIA 279

antennina 280

indivisa 280

ramosa 282

arborescens 282

Arum 75

ATHECATA (suborder)

ATUACTYLID^E 87

ATRACTYLIS 87

arenosa 88

BIMERIA 101

vestita 103

BOUGAINVILLIA 108

ramosa 109

fruticosa 110

muscus Ill

CALYCELLA 205

syringa 206

fastigiata 208

CAMPANULARIA 160

rolubilis 160

Hincksii 162

integra 163

caliculata 164

verticillato 167

flexuosa 168

angulata 170

Page
CAMPANULARIA

neglecta 171

exigua 172

decipiens 173

? gigantea 174

? fragilis 175

? raridentata 176

brcviscyphia 1 64

elongata 175

gracillima 202

CAMPANULARIID^E 137

CAMPANULINA 186

acuminata 186

tennis 186

repens 189

turrita 190

CAMPANULINHLE 186

Candelabrum 75

Capsularia 37

ClONISTES 134

reticulata 135

CLADONEMA 61

radiatum 62

CLAVA 1

multicornis 2

squamata 4

cornea 5

leptostyla 6

nodosa 9

diffusa 9

CLAVATELLIDyE 69

CLAVATELLA 70,320

prolifera 73

CLAVID.E. 1

Clavula Gossii 14

CLYTIA 140

Johnstoni . . . 143

330

INDEX.

Page
CLYTIA

poterium 164

COPPIMA 218

arcta 219

mirabilis 219

COPPINIID^E 218

CORDYLOPHORA 15

lacustris 16,32-4

CORYMORPHA 125

nutans 127,323

nana 130

CORYNE 37,318

pusilla 39

vaginata 41

vermicularis 42

f'ruticosa 44

VanBenedenii 45

? nutans 325

Lisferii 50

pelagica 59

Briareus 59

Stauridia 62

Cerberus 68

ferox 319

CORYNID.E 37

CORYNOPSIS 34

Alderi 34

Cotulina 234

CUSPIDELLA 209

humilis 209

grandis 210

costata 210

DlCORYNE 105

conferta 105

DIPHASIA 244

rosacea 245

attenuata 247

fallar 249

pinaster 252

tamarisca 254

pinnata 255

alata 258

Dynamcna 244, 259

Dysmorphosa 27

Echinochorium 19

ECTOPLEURA 1 23

Dumortierii 124

Eucope 146

EUDENDRIID.E 79

EUDHHDRIUM 79

rameum 80

ramosum •. — 82

annulatum 83

arbuscula 84

capillare 84

Page

ElTDENDRIUM

vaginatum 80

insigne 86

bacciferum 102

FILELLUM 214, 323

serpens 214

GARVEIA 101

nutans 102

Gcmmaria 58

GoNOTriYR.-EA 180

Loveni 181

gracilis 183

? hyalina 184

Grammaria 211

GYMNOCIIROA (suborder) 309

Gymnatoka 1, 309

HALECIID.E 220

HALECIUM 220

halecinum 221

muricatum 223

Beanii 224,324

labrosum 225

ten^llum 226

plumosum 227

geniculatum 229

sessile 229

Halicornaria 294

Hermia 37

HETEROCORDYLE 107

Conybearii 107

Hippocrene 108

HYDRACTINIA 19

echinata 23

polyclina 23

HYDRACTINIID.E 18

HYDRALLMANIA 273

falcata 273

HYPRANTHEA 99

margarica 100

HYDRA 309

viridis 312

vulgaris 314

oligactis 315

attenuata 316

viridissima 312

grisea 314

brunnea 314

fusca 315

verrucosa 315

pallens 316

HYDRID.E 309

Hydrina 309

LAFOEA 198

clumosa.. . 200

INDEX.

337

Page
LAFOEA

fruticosa 202

parvula 203

pocillum 204

pygmsea 205

LAFOEID.E 198

Laomedea 146

LARID/E 35

LAR 36

Sabellarum 36

LEPTOSCYPHID.E 196

LEPTOSCYPHUS 196

tenuis 197

LOVENELLA 177

clausa 177

Man iccUa 103

Margelis 108

Monopyxis 146

MYRIOTHELA 75

Phrygia 77

arcfica 77

MYRIOTIIELID.E 75

Nemertesia 279

Nigcttastrum thuja 276

OBELIA 146

geniculata 149

gelatinosa 151

longissima 154

dichotoma 156

flabellata 157

? plicata 159

OPERCULARELLA 193

lacerata 194

OPIIIODES 230

mirabilis 231

Orilwpyxis 160

Parypha 114

PENNARIIDvE 131

PERIGONIMUS 89

repens 90

sessilis 93

palliatus 93

vestitus 94

serpens 95

?linearis 96

? miniatus 97

?coccineus 97

? bitentaculatus 98

? quadritentaculatuB 98

PLUMULARIA 294

pinnata 295

setacea 296, 325

Catharina . . . 299

Page
PLUMULARIA

echinulata 302

similis 303

obliqua 304

halecioides 306

frutescens 307

PlA'MULARIID.E 279

PODOCORYNE 27

carnea 29

areolata 32

proboscidea 317

Beficularia 214

immersa 214

Rhizocline areolata 32

SAL ACIA 211

abietina 212

Sarsia 48

SERTULARIA 259

pumila 260

gracilis 262

operculata 263

filicula 264

abietina 266

argentea 268

cupressina 270

fusca 272

flexuosa 235

cricoides 235

Hibernica 235

Ellisii 235

patagonica 241

nigellastrum 245

Margarcta 252

fuscescens 255

usneoides 263

abietinula 266

fastigiata 268

nigra 272

lonchitis 277

seficornis 282

secundaria 298

Gorgonia 307

SEKTULARELLA 234

polyzonias 235

Gayi 237

tricuspidata 239

rugosa 241

tenella 242

fusiformis 243

SKUTULARIID/E 233

Sertularlna 137

Skenotoka 137

Spadix 75

STAUKIDIID.E 61

STAURIDIUM 67

z

338

IN])EX.

Page
STAURIDIUM.

productum Ox

Hthenyo 4<S

Stipula 37, 319

SYNCORYNE 48

eximia f>0

Sarsii 52

gravata 53

deoipiens 5(5

pulchella 57,310

ferox 319

Lov6nii 52

Synhyclra 19

Thqmnocnidia 108

TlIAUMANTIAS 178

inconspieua 179

TIIECAPIIOKA (suborder) 137

TAoa 220

THUIARIA 275

thuja 275

articulate 277

TRICIIYDRA 215

pudica 210

TRICIIYPRIIVE 215

TtTBICLAVA 10

lucerna 11

TUBICLAVA

Page

TrnuLARiA ........................ 114

indivisa .................. 115,322

larynx ........................ 118

coronata ..................... 119

simplex ...................... 121

bellis ........................... 122

attenuata ..................... 122

humilis ........................ 123

gracilis ........................ 119

calamaris ..................... 322

TUBULARIID^: ..................... 114

Tubularina ........................ 1

TURRIS .............................. 13

neglecta ........................ 13

VOHTICLAVA ........................ 131

humilis ........................ 132

proteus ........................ 133

Wrightia acumin at a ............ 187

ZANCLEA ........................... 58

implexa ........................ 59

ZYGODACTYLA ..................... 191

vitrina . .192

THE KN1).

PRINTED BY TAYLOK AND FRANCIS,
REP LION C'OUIIT, FLF.ET STRKFT.

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