. THE DANISH INGOLF- EXPEDITION.
es ; VOLUME V.
Cyr eae S
a ee Mine, acer, i

—

COPENHAGEN. Aes
) BY BIANCO LUNO.

THE DANISH INGOLF-EXPEDITION.

VOLUME V.
6.

a RGN oe:

(RAR Ts I3)

BY

HJALMAR BROCH.

WITH 2 PLATES AND 20 FIGURES IN THE TEXT.

4 3
“onal Muses /
COPENHAGEN.

PRINTED BY BIANCO LUNO.

1g16.

Y

CONTENTS

Page ,
LCL A CC A sedate ahs,s Grats eievara i ctetacs er arcsaie smn anemeau sneyansin sl dieteseidutnes 1]
EMTIELOGUUCtO Rye IN OLES a aeiesee east ieieietatere ee eiareic pera ceclavaerens le 3

a. The Hydroid Gonophores bearing on classification. 4 _

b. The comparative anatomy of the nourishing individ-

uals and the system of the athecate hydroids ._... 7
II. Athecate Hydroids of the northern Atlantic .......... 11
CCH Oleg Capreata) eee aati ans eicpsrcmmariieiitste se eke aise cies: II
Bamiliys Coryrtd ae’ tic. siae sreiapeare ance tones piss tert grag eke. sper$ II
Coryne Gaertner ......4- Sesto aree nis Ske FON a LS,
Corgine Sarste (ily Orv.EL) ioe scene cnc eae clases cee ariel
=) Lodertr Naw allS))| glee ascent ean nee ok 15
a Peestlla GOLEM OKe, cana des sen ahieseenas.s =, seicers 16
— sp. aff. Aincks? Bonnevie.............. 18 |
Bamily Myriothelzdae . 50. ice cen wee ece Eaters eted LO.
Migr 20tHelan Nici O: ue Sit ie sere 6 as tise oe ayn oats 19)
Myriothela phrygia (Fabricius)................ 19
aRtaa tea i yy 222 ite Lexgetrd Leyes iciets teneaae wash Sigte easaler a erevaentav ses seat 21
IRA TAM Ob beh =) See aden ae De Senin tars 22
Tubularia pulcher (Seemundsson)............ 22
— PE LVOR aT Aye Di) itp ath al cir ee oe Ip oy er Be Se 24
—_— VELAUS BIO CCK... aivcicins cpetre sve baie autte o- 25
— larynx Ellis et Solander.......... 27
= S Papi e tie awa etn ae esis eet ak ods 28 |
CompmorpRa Nis SiAtS. sth etete sine ect asta ats 6,2 2 mc 29 |
Corymorpha nutans M. Sars .....2.0.02:0.005% 31 |
-- LACUS IM, WS AL Sie yaa cae sjn\ desi thee, Wenaucts tenes 32 |
os groenlandica (Allman),............. 33

Corymorpha sp. indet............. ayaa

Section /ilifera .
Family Clavidae
Clava Gmelin.....

Clava multicornis (Forskal)

Mer ond cNiOG MANY, ccc ale sccs cae seo asi ae iene

Merona cornucopiae Norman ..................

Monobrachium Mereschkowsky ................

Monobrachium parasitum Mereschkowsky...

Family Bougainvillitdae........

Hydractinia Van Bemedien! 25... 200 dee osgns ee

Hydractinia Sorsit Steenstrup................

echinata: (HVemimnig)\ enc w. ae eae ees

= CaHICA BETS HG wa kinase oieishiseie:
Bougainvillia VESS OMe date couse ies neers oe

Bougainvillia conferta (Alder)..................

LCxALONUNUSE NOLL SP art ates iaencrsp cicero he tie tao

Perigonimus repens (Wright)...............005.

— abysst Gu Ole Siar Sec iis case ae

— FOSEUSN (NED OcaitS)) bea cepaye ne abeheie- steno ders

Fa mily UAE ATO QET TT on Eo eens Re
Ludendrium, Fone nD er Pye. cme tas 6 as ee elas cic
Eudendrium rameum (Pallas)............0.00..

= ramosum (inné)..........
_ Wrachiv War tliat vrei. 2\<0,svelens ciel iets
— annulatim, NOTMA IM. «4. 62 ee celta es
— COPLUAKEWAUG Gris aa -cereiersiee eis aeons

Preface.

The investigation of the large Danish collections of hydroids from the Faroe Islands, Iceland,
and Greenland, and the researches into the interesting material brought home from the Ingolf
Expedition, have realised great results. In fact, several points of dispute as to the classification of
northern species have been settled. In the first place, the Danish collections contain original specimens
of some species which have been described as new several times after being originally recorded. In
other cases, the large number of specimens tend to bridge the division between species which have
hitherto been looked upon as “good” ones. It is, indeed, a matter of regret that deficiencies of diagnosis
and inaccuracy of design have frequently put obstacles to the recognition of species previously recorded,
and that the literature has, consequently, been encumbered with synonyms which we should rather
have done without. This inconvenience, in fact, enforces the necessity of giving full and exhaustive
accounts of every single species. The American investigators, indeed, on the pattern of Nutting
have iong tried to give brief diagnoses and drawings of all American species. But it must be observed
that, because of the impressionist way of drawing, the illustrations are, as a general rule, somewhat
wanting in accuracy, and to the brief diagnoses there is the objection that they are often too summary
to give exhaustive account of the distinguishing features. On the whole such weak points as appear
in the last works of Allman, have gone down to his epigones. Great difficulties, indeed, are in this
way given to students of the geographical distribution of the hydroids. No doubt, more species than
those which are at present pointed out by literature, are common to the European and the American
seas. But in general it proves impossible to form, on the ground of the brief diagnoses, a well-founded
opinion as to the virtual qualities of many species. As far as the European species are concerned, we
are fortunate in possessing the classic work of Hincks, A History of the British Zoophytes. However,
since the appearance of that work, plenty of fresh subjects have been added by descriptions of several
species and genera which can hardly all be maintained, and publications have of late appeared in such
abundance that it proves difficult to students of this group of animals to find their way through the
crowded matter.

These are the reasons why I have tried to give new and detailed diagnoses of every single
species in question. The diagnoses are essentially founded on the copious material occurring in the
Danish collections. Of synonyms I have only selected those of absolute necessity. Detailed accounts
of synonymy are found — as far as earlier literature is concerned — in the excellent treatises of Bedot,

The Ingolf-Expedition. V. 6. I

HYDROIDA

IS)

Matériaux pour servir a Vhistoire des Hydroides, and — regarding recent literature on northern
hydroids — in the groupings framed by Jaderholm (1909), Broch (1909), and Kramp (1914). As far
as possible, the various species are accompanied by maps illustrative of the geographical data in the
northern Atlantic. Besides the collections the recent literature has served as basis. In this respect
the groupings occurring in the works of Bonnevie (1899), Jaderholt (1909), Broch (1909), Se-
mundsson (1911), and Kramp (1914), have proved particularly available.

I have made it a point to define precisely the limits of genera and families by full diagnoses,
and at the same time I have tried to account for the leading principles I hold to for the purpose of
division and classification. The various authors have maintained various opinions as to the systematic
principles of classification; many of them have disregarded phylogeny and allowed biological considera-
tions to play a predominant part; consequently the circumscription of genera has been practised in
most various ways. To leave no opening for misunderstanding I have thought it necessary to give
a detailed account of each species in question, even if the work should be delayed and grow a little
broader than I wanted. However, I hope that in this way the extensive and methodical Danish col-

lections will tell better and to fuller advantage than otherwise.

Trondlyjem the 22nd August 1915.

I. Introductory Notes.

Scarcely in any other part of the animal world greater difficulties are thrown in the way of
the systematist than those occasioned by the lowest Coelenterata, impeding the attempts to establish
a natural grouping of the hydroids and their attendants, the hydromedusz. This is due not only to
the actual deficiencies of our knowledge of these low organisms, but also to the fact — as pointed
out by Kiihn in his excellent summary (1913) — that the groups present partly a confused series of
adaptations and phenomena of convergency, partly the occurrence of medusz of widely divergent
development as companions of closely allied hydroids or, vice versa, closely allied meduseze accompanying
hydroid polyps divergently developed. It is a striking fact that in certain species, for instance the
Codonida, the phylogenetic development and differentiation of form of the medusz have been com-
paratively stunted, whereas the polyps (Coryuide, Pennariude, Tubularide) have developed hetero-
geneously so as to present a large series of various forms. The exact reverse is represented
by the homogeneous polyps of the family Bougainvilliide forming the nurse generation of the hetero-
geneously developed hydromeduse of the families M/argclide and Tiaride. The possibility of construct-
ing a safe system common to medusze and hydroid polyps, indeed, appears remote. For in the first
place the two “generations”, on account of their excessive abundance of species, have had to be treated
separately, each generation by specialists of its own, and moreover, we are in fact still in the dark as
to which of the two generations is to be regarded as the primitive or the phylogenetically older.

When looked upon as a whole the group of Zoophytes must be characterized as a very low
group of animals. In the nurse generation as well as in the free-swimming medusz the structure
of the individual is very simple, though the meduse after all must be said to be a little higher
organised than the polyps. In addition to the two primary layers of cells, the endoderm and the ecto-
derm, occurs in the medusze a “mesogloea”, whose descent from one or the other of the primary layers
is not yet definitely ascertained as far as all species are concerned. However, a mesoglcea also occurs
with some hydroids, for instance the “parenchyma” of the Zzdelaride, which is a typical endodermal
formation.

To students of the hydroids it very soon becomes obvious that the leading systematic characters
have been derived from such criteria as urge themselves on a superficial view of the animals, while,
contrarily to the method practised in investigating most other groups of animals, the inner

anatomy is all but entirely left out of account. This is due to the generally accepted view that the

*

be

4 HYDROIDA
structure of the hydropolyps is throughout quite homogeneous and accordingly affords no holds of
use to the systematist. A careful study, however, of the slight information occurring in the literature as
to the structure of the polyps, will show that the old view is wrong. In this connection it will be
sufficient to refer to the excellent passage written by K ithn (1913), Die Ausbildung des Polypenkorpers,
in which are mentioned several examples of the heterogeneous structure of the polyps in the various
groups of hydroids.

Nevertheless Kithn himself (1913), in constructing his system of the hydroids, has, according
to the old practice, left this fact almost wholly out of account. I will afterwards come back to the
subject and point out how unreasonable it is to set aside this part of systematics even though a
thorough investigation of the anatomy of the polyps may seem almost impracticable because of the
state of preservation in which the hydroids generally occur in the materials of the great expeditions
and collections. In fact, it is confirmed that evinsen (1893) is right, emphasizing that the systematist
in treating of hydroids should rather lay stress on all about the nourishing individuals than on the

varying development and organisation of the generative individuals.

a. The Hydroid Gonophores bearing on classification.

Our knowledge of the hydroids has advanced a vast stride ahead owing to the thorough
researches of Kiihn into the development and the organisation of the gonophores (1910). As to the
importance of the gonophores to systematics, it has lately (1913) been asserted by the same author
that no weight whatever can be given to the various gonophoral development, but that particular
stress should be laid on the structure of the full-grown gonophores. On account of difference of structure
he distinguishes between four types of sessile gonophores: eumedusoids, cryptomedusoids, heteromedusoids,
and, finally, the simple gonophores, called styloids (Bonnevie 1898). The eumedusoid gonophores, indeed,
retain the structure of the medusa throughout, and occasionally breaking away (Campanularia integra
Me. Gillivr. — Agastra mira Hartlaub) occur like defective medusz. The structure of the crypto-
medusoid gonophores is more reduced. Certainly they keep their endocodon and their umbrellary cavity,
but have a single-layered umbrellary endoderm; however, also of cryptomedusoids occur exceptional
instances breaking away, as in Pachycordyle Weismannt Hargitt. The heteromedusoids are entirely
wanting the umbrellary endoderm, and the inner umbrellary ectoderm is formed by delamination, not
by invagination of the outer ectoderm (endocodon). The simplest gonophores, finally, are without any
trace of medusoid organisation. These four types of sessil gonophores Kithn (1913) regards as char-
acters important to the systematist for the division of hydroids into genera.

Stechow (1913) in his important work on Japanese hydroids occupies another standpoint,
attaching more importance to the conditions of the gonophores. Thus he draws nearer to earlier
principles of classification, but at the same time he tries to make his systematic division more manage-
able by drawing out characters from the outward morphology of the colonies, thus effecting the
transition to the American school. The Americans, headed by Nutting, look on classification only as
“a matter of convenience”, and accordingly in their groupings, as a matter of fact, relinquish the idea
of constructing a natural system aiming at summing up and drawing by critical sifting of the char-

acters a skeletonlike picture of the phylogenetic affinities of the group of animals in question. Con-

HYDROIDA

On

sequently the system brought about by the American investigators, picking up heterogeneous char-
acters, is indeed, as I have shown in an earlier treatise (190g), to a great extent one of arbitrariness,
placing the species now in one, now in another genus, according to the character it is thought desir-
able to emphasize at the moment. The system has, in this way, become a matter of chance.

Before proceeding to the special explanation of the several species of hydroids and their occur-
rence in the seas of the northern Atlantic, we, therefore, must try to realize, from a systematic and
phylogenetic point of view, the value of each single character. In the first instance the question must
be answered what part the gonophores play as to the phylogeny of the hydroids or, in other words,
what importance has to be attached to the gonophores and their conditions for the purpose of
classification.

The application of the characters of the gonophores as distinguishing marks of higher system-
atic unities, of families, or of subfamilies, has been abandoned by all modern investigators of the
hydroids. On the other hand, it is held by several investigators that they are of importance as to the
limitation of genera. The last significant publications maintaining this view, are those of Kiihn (1913)
and Stechow (1913). Ktihn, however, applies the characters of the gonophores with much caution
and discretion, while Stechow, as a glance at his tables (1913, p. 36 and the following pages) suffices
to show, undiscerningly recurs to the principle of laying the main stress on the “medusa” as contrasted
with the “sporosac”. In fact, as long as the limits between these designations are not more precisely
defined, they will be subject to much arbitrariness. An interesting instance is afforded by the point
in dispute, where the limits are to be drawn between the genera Coryne and Syncoryne. The old
criterion, accepted by Allman and other investigators, was the free medusa as contrasted with the
fixed gonophore or sporosac, and, to all appearance, it is the same limitation Stechow tries to
maintain in his table. Indeed, this principle of limitation was only supportable on the ground of the
deficient knowledge of the organisation and development of the hydroid gonophores attained to in
Allman’s days. Kihn, therefore, (1913, p. 229) is seen to take quite another departure, defining the
Syncoryne as including all species having “medusze”, while the Coryze is distinguished by styloid
gonophores. It is evident from Ktiin’s previous argument (l.c. p.174) that under “imédusz” he also
includes the eumedusoids which normally do not break loose, and that accordingly Corywe, in his
opinion, exclusively embraces species having styloid gonophores.

Parallel to these genera Stechow also treats of Podocoryne (with medusee) and of //ydractinia
(with “sporosacs”). Kiithn (1913, p. 227) groups them in the following vague way:

Podocoryne |
Hydractinia J

From his premises (lc. p. 226) it appears that he agrees with most modern investigators, think-

Medusen (Margelinen), Eumedusoide, Cryptomedusoide, Styloide.

ing it right that the two old genera should be merged into one, //ydractinza; for he states that in
fact we have here before us a series of closely allied forms, in which “zwischen Arten mit Vollmedusen
und einfachen Medusoiden die verschiedensten Ubergiinge bestehen”. Thus Kiihn, elsewhere considering
the characters of the gonophores as significant generic criteria, in this place actually reduces them
to mere specific characters.

In another connection Kiihn (1913 p. 197) gives an instance of the fact that the sexes in

6 HYDROIDA
one and the same species can be distinguished by different types of gonophores; thus the female
gonophore of Laomedea flexuosa Hincks is heteromedusoid, while the male gonophore is styloid.
This strongly defined sexual dimorphism is most interesting, and the question is obvious whether the
case is a solitary one, or if in other species other types of gonophores, of those stated by Kuhn,
might perhaps be found united in one and the same species. On that account I have (1915) more
closely examined the development of the gonophores of, among others, the 7wézzlaria indivisa Lin.
and the Zubularia regalis Boeck, two species in which a marked sexual dimorphism is found pro-
nounced in the external characters of the gonophores. The examinations resulted in the startling result
that the female gonophores of both species are eumedusoid, though not equally high in medusoid
organisation, whereas the male gonophores of both species are heteromedusoid and of entirely the
same organisation and development as the gonophores of the genus Lampra Bonnevie (1898) (comp.
Broch rors). It is owing to the gonophores that Lampra is separated from Corymorpha, the latter
genus producing free medusze or having gonophores eumedusoid. Acting on this principle of division,
as far as the species of the genus Zwbelaria are concerned, we should have to separate the male
Tubularia indivisa and Tubularia regalis as a new genus, while the female individuals belonging to
the same species would retain their places'.

The outcome of the searching studies of the last years shows, indeed, that in proportion as a
greater number of species have been examined, the more evidently the characters of the gonophores
appear as criteria of species. The increasing knowledge of the gonophores makes ever clearer that
the gonophores alone cannot form the base of any division of genera, but at most serve as second-
arily corroborative.

The free meduszee show throughout a greater abundance of forms developed than the polyps,
which are more conservative. No doubt, the medusee present a series of phenomena of adaptation
and, accordingly, display several characters of convergency, to which the systematists are inclined to
attach a greater phylogenetic value than is their virtual due. Nowhere, I dare say, the adaptations
to habits of life and the accommodations to varying physical conditions play such a part as with the
pelagic organisms, to which the slightest variation of salinity and of temperature causes great
changes of viscosity of the surrounding water, decisive of the adaptation of their suspension organs.
Therefore, the hydroid systematist should not lay too much stress on the statements of the medusoid
specialist as to the systematic grouping of the free-swimming generation; phylogenetically the char-
acters of the nurse generation are of the greatest interest. A similar state of things urges itself with
the sessile gonophores. It is a circumstance of vital importance to the maintainance of the species,
that the generative individuals are able to accommodate themselves quickly to the peculiar conditions
of life to which the species is subjected. What I observed in my treatise on the Sty/asteride (1914),
is fully applicable (or even more so) to the case under consideration: “Owing to their conservatism in
development the polyps are of the most important phylogenetic interest. The gonophores, the genera-
tive individuals, on the other hand, might almost be said to be a playball in the hands of chance
biological conditions and thus phylogenetically have much less interest”.

1 The possibility of a fusion of four species is precluded, as in Zbularia indivisa and in Tubularia regalis G and 2

occur in the same colony.

HYDROIDA 7)

On account of their dependence on outward conditions and their power of plastic accommodation
to biological influences, the gonophores are unsuitable for basis of division into genera. On the other
hand, the genera, owing to the conditions of the gonophores, often fall into a series of biological
groups (or subgenera). The systematists who lay the main stress on the gonophores in establishing
the system, in fact apply biological conditions as fundamentum divisionis, and let phylogeny, the pro-

perly governing principle of systematic inquiry, recede into the shade.

b. The comparative anatomy of the nourishing individuals, and the system of the
athecate hydroids.

An exact review of the researches of the last years makes ever clearer, as also appears from
the statements above, the correctness of Levinsen’s view (1893), maintaining that in the great classifica-
tion of the hydroids the main stress must be laid on the peculiar conditions of the nourishing polyps,
and reducing at the same time the modifications of growth and the conditions of the gonophores as
characters of subordinate importance. Later investigators’ have, indeed, attached ever more importance
to the conditions of the polyps. But in so doing they have almost exclusively taken into considera-
tion such morphologic criteria as urge themselves on a superficial view of the polyps. The inner
anatomy, on the contrary, has been disregarded. Kitthn (1913) certainly by the way points out that
the inner anatomy can be different in the different groups. He treats (I. c. p. 50) at some length
of the peculiar structure of the polyps of the Zzézlaritd@, and points out the multifarious development
of the ¢hecaphores. But in drawing the bases of his system he makes no attempt to turn these features
to further account.

As a result of searching inquiries, the structure of the polyps in the different genera and
families has turned out not to be quite so homogeneous as it has been generally held. Both in the
construction of the ectoderm and in that of the endoderm differentiations occur, which may be char-
acteristic of greater or smaller groups of species and give us several holds for judging the systems
drawn up for hydroids in the course of time.

Therefore, it will here be appropriate to give a brief synopsis of the more important peculiarities
of anatomy distinguishing the various groups of athecate hydroids, in order to apply them afterwards
to drawing up the system of the group.

The ectoderm, deciding by the disposition of its elements whether the tentacles have to be
claviform or not, has, to some extent, been turned to account as fundamentum divisionis. The clavi-
form shape is particularly due to the accumulation of the stinging cells on the tips of the tentacles,
while the tentacles are filiform when the nematocysts are more equably distributed. A third type of

tentacles, which, as far as is known, is found with all thecaphore hydroids, occurs in the Eudendride;

« Works like that of Poche (1914) I leave out of account. That sort of “zoology” which is based not on study of
the organisms themselves, but only on what may be beaten up from books, here debouches in the construction of airy castles
of complicated systematics, which does not advance zoological science by a hairbreadth, but only contributes to increasing
the systematic confusion. Between “regnum” and “family” are inserted 34 — thirty four — degrees. It is a matter of regret
that we do not learn how many osculant categories must be placed between “family” and “individual” to give a “full” picture

of nature. But this will suffice to illustrate the scientific value of the work.

8 HYDROIDA

here the stinging cells are arranged in dense transverse belts round the tentacles so as to give these,
when distended, a peculiar transversely striped appearance.

On the ground of filiform and claviform tentacles Kiithn (1913) divides the athecate hydroids
into the two principal groups of /7lifera and Cafitata. However, we find in the latter group also
instances of filiform tentacles; in the Pexaride filiform tentacles occur together with claviform ones;
in the Zwbelariéde, on the contrary, the claviform tentacles have disappeared, at any rate in the polyps
fully developed. Kiihn (lc. p. 228), therefore, also makes the reservation that the tentacles are “dauernd
oder in der Jugend geknépfit”. Embryological studies on Corymorpha have, in fact, shown that the
actinula has claviform tentacles (Torrey 1907, Hartlaub 1907). However, this state of things cannot
be generalized as a matter of course to embrace the 7du/aria; on the contrary the figures of Allman
(1872) show quite distinctly that the actinula in Z2zdeularia larynx and Tubularia indivisa have filiform
tentacles, and inquiries into the Zwdularia regalis in the Trondhjem Fjord have shown no trace of
capitate tentacles during the development of the actinula. Nor do here claviform tentacles occur in
full-grown polyps.

But even though the definition of Kitthn must be characterized as erroneous so far, there is
another criterion showing that his division of groups is correct. A searching study of the very nemato-
cysts, shows, as a matter of fact, that the athecate hydroids fall into two large principal groups, cor-
responding to the Cafztata and the /7lifera stated by Kuhn.

In the hydroids occur two characteristic principal forms of nematocysts (Pl. I, figs 1—7). In all
the Capitata we find large oviform or almost wholly spherical nematocysts of the same principal type
as is often mentioned in the /4ydrva. These large nematocysts are always accumulated on the tips of
the claviform tentacles, as in the Coryze, while on the filiform tentacles of the Zudwlaria they are
more equably distributed all over the ectoderm of the tentacles. However, these stinging capsules are
also found elsewhere in the ectoderm of polyps, as is the case with Monocoryne and Myriothela. In
the last mentioned form the nematocysts, like those of AZ/lepora, have developed dimorphicly; besides
the typical oviform nematocysts we find here a larger and more slender oval form; in general the
latter nematocysts are outnumbered by the oviform ones, but still they amount to a large percentage
of the total stock of stinging capsules occurring in the animal. In the A@//efora this type of nemato-
cysts, judging from the figures in hand, is rather broad.

The rest of the hydroids are distinguished by quite a different type of nematocysts. The pre-
dominant type is a very small, all but rod-shaped nematocyst, particularly occurring in the tentacles,
generally accumulated in belts, vertically on the tentacle axis, giving the tentacles, when wholly
stretched out, a peculiar transversely striped appearance, like that of the tentacles of the Audendrium
recorded. Concurrently with this typical small nematocyst distinguishing all /7fera sometimes occurs,
finally, a somewhat larger form, as in the Hwdendriwm and the Stylasteride. In the Eudendrium
Wriehtt we find in the tentacles only small rod-shaped stinging capsules; on the contrary in the
basal whorl of stinging cells of the polyp body of the species in question the capsules are much larger,
though keeping a slenderly oval appearance. It is strange that this large type of the Ladendrium
and the S/lasteride should appear almost entirely consistent with the aberrant slenderly oval nemato-

cyst with the Myriothela. The simultaneous occurrence of the type in so different and so highly

HYDROIDA 9

organised forms suggests, indeed, that we have before us phenomena of convergency, the cause of
which is at the moment quite inexplicable.

However, not only the ectoderm itself and its elements are of interest to comparative anatomy.
The derivates of the ectoderm are of great importance. In the same way as the ectoderm of
the stem secretes a periderm, we find that with all thecaphore hydroids a chitinous hydrotheca is
secerned by the ectoderm of the polyp. Remarkably enough, a parallel is found also in a single genus
of the athecate hydroids, the Perigonimus. In this genus the ectoderm of the polyp secretes a
“pseudohydrotheca’, a hydrotheca-like, folding periderm case of a jellied substance surrounding the
basal portion of the polyp up to the tentacle whorl. The first inquiries as to the pseudohydrotheca
have been made by Hadzi (1913 and 1gr4). The pseudohydrotheca is distinguished from the real
hydrotheca in having no free margin, but being distally firmly connected with the ectoderm of the
polyp so as to be indistinguishable, on a superficial view, when the polyp is wholly distended. On the
contrary, when the polyp is contracted, the pseudohydrotheca is, in general, easily discerned, forming
a richly folded cover round the basal portion. The pseudohydrotheca bears some resemblance to the
genuine hydrotheca by the way in which the polyp is attached to it, the supporting lammella of the
polyp being basally connected with the pseudohydrotheca by a whorl of small chitinous pro-
minences. Similar chitinous prominences are also seen, for instance in Hewdendrium, connecting the
soft parts of the stem with the periderm cover; systematically, however, no particular interest can be
attached to them.

Also in the endoderm diversities of great interest are found. The simplest, most homogeneous
shape is represented by the gastric endoderm of Clava (Broch 1911), forming a homogeneous epithel-
ium for absorbing the nourishment, from the orifice of the mouth to the passage of the polyp into
the stem; almost all of the cells of the gastric endoderm are filled with larger or smaller grains
showing a strong affinity to Delafield’s hematoxyline (“nutritive cells’ and “albumen cells”, comp.
Schneider 1902). As to Coryne, the state of things is quite different; here the endoderm in the
portion nearest to the mouth is extremely rich in mucous gland cells, while the digestive cells are
comparatively few in number. In Coryze we must consequently distinguish between the oral
portion secerning mucus and the part of the endoderm of the polyp which is the proper gastric or
digestive portion. The difference between these two endodermal zones appears still more distinctly in
Myriothela; the glandular cells are here densely concentrated on a small portion near to the mouth,
strongly conspicuous by its clear blueing after being treated with Delafield’s heematoxyline; the
other endodermal cellular forms have almost wholly disappeared in the glandular zone with
Myriothela. In Tubularia, on the contrary, the glandular zone has disappeared, so that the endoderm
here by its homogeneous appearance all over the polyp strongly recalls the case of Clava.

A rather different state of things is found in the Bougainvilliide. Here, indeed, mucous cells,
occur in the oral endoderm of the polyp. But the bulk of the cellular elements in the oral portion as
far as the whorl of the tentacles, is constituted by cells which appear indifferent to the nutritive elements.
All the cells here have small nuclei strongly concentrated, while in the gastric endoderm taking the
nourishment, from the whorl of tentacles and downwards, the nuclei are large, with open chromatine

net-work. This condition of things is still more pronounced in Hwdendrium, the mucous cells of

The Ingolf-Expedition. V. 6. ez

Io HYDROIDA

which, however, are most frequently concentrated in the proboscis, closely to the basis of the tentacles,
where the entrance to the proper gastric cave is found.

Thus there is throughout a typical difference between the Capzfata and the Filifera as to
endodermal matters, though the C/ava apparently presents an intermediate form or a form of depar-
ture from which the other types are derivable. Simultaneously the /7%/i/era, as far as can be judged
from the data in hand, bear a typical resemblance to the thecaphore hydroids, and here the parallel
between the Audendrium and the Campanulariide is particularly obvious. Whether this is owing to
a closer affinity or it must be explained only as a phenomenon of convergency, we must at present
leave unanswered, because of our deficient knowledge of the group.

A single family, the 7zédelariide, shows an anatomic peculiarity, as with the species of this family
there occurs a peculiar m’esogloeal formation. At the basis of the large tentacles the endoderm has
developed a thick supporting cushion formed as a ring of mesoglceal tissue of large cells round the polyp.
This leans inwardly on the supporting lamella, and is bounded against the axial endoderm of the tentacles
by a delicate membrane, which in some cases it is rather difficult to point out.

Hollow tentacles occur in two ways. In their original shape they are, as is the case with
Hydra, openly communicating with the gastric cave of the polyp. This state of things, however,
has ceased with most hydroids and cannot be found in any of our northern species. In these, on the
other hand, occasionally occurs, as in Clava multicornis and in Myriothela a central cavity in
the tentacles, at any rate in their basal part. This cavity, however, does not communicate with the
gastric cave of the polyp, but is basally bounded by the unbroken supporting lamella. This central
cavity of the tentacles, as it is represented by well-developed Clava mudlticornis, might be looked upon
as a primitive condition of things. However, in forms so highly organised as AZyriothela, it must
sooner be considered as a secondary phenomenon, which cannot have any direct correspondence with
the primitive condition of things in Hydra.

In Ayriothela the tentacles show a peculiar structure, elsewhere unknown in the hydroids.
The matter is more precisely described by J&derholm (1905). The supporting lamella is in the
thickened distal part of the tentacle transformed into a cushion constructed by delicate radially
placed fibres, showing no cellular structure and densely crowded. They seem to be intended for
strongly stiffening the distal portion of the tentacles and for making the armed outmost portion of
the tentacles larger and more powerful of resistance.

On the ground of the anatomical features stated, and of morphological characters hitherto turned
to account in systematics, is brought about a system which, as far as the athecate hydroid families

are concerned, can be summed up in the following key of determination:

A. No formation of gonophores. Eggs and sperms, developed in the wall of the polyp. The tentacles
— if such ones occur — hollow, openly communicating with the gastri¢ cave (Sectio Simplicia nov.)
Fam. //ydride.

B. The generative cells developed in special gonophores.
I. The polyps with large, broadly oval or spherical nematocysts (Sectio Capitata K thn).

a. The tentacles of the polyp wholly or in part claviform.

HYDROIDA II

1) The polyp having only one kind of nematocysts. The claviform tentacles of simple struc-
ture, having no central cavity and no particularly developed supporting lamella.

a. All tentacles claviform. Fam. Corynide.

8. The distal tentacles claviform; proximally a whorl of filiform tentacles. Fam. Pexnariide.

2) The polyps, besides having oviform or spherical nematocysts, also provided with slenderly
oval or nearly cylindrical stinging capsules.

g. Without calcareous skeleton. The claviform tentacles having a central cavity, greatly
widened distally, but not openly communicating with the gastric cavity of the polyp.
The supporting lamella, in the outer portion of the tentacles, developed into a thick
radial fibrous supporting tissue. Fam. A/yriothelide.

f. Colonies with calcareous skeleton. The tentacles of simple structure, having no central
cavity. Fam. JZlleporide.

b. All the tentacles of the polyp filiform, arranged in two main circles:

1) The proximal (basal) whorl of tentacles leaning against a well-developed mesoglaal cushion.
The polyps of radial symmetrical structure. Fam. 72zdulariude.

2) The mesoglcal formation at the basis of the proximal whorl of tentacles almost wanting,
owing to radial canals. The structure of the polyps bilaterally symmetric. Fam. Aranch-
zocerianthide.

Il. The nematocysts always only slender, the small ones quite rod-shaped. (Sectio Filifera K tihn).
a. Colonies without calcareous skeleton.

1) The tentacles irregularly spread all over the polyp, or reducible to a single large tentacle.
The endoderm not differentiated into oral endoderm and gastric endoderm. Fam. Clazvide.

2) The tentacles forming a main circle round the polyp. The endoderm differentiated into
an oral endoderm and a gastric endoderm.

g. The polyps fusiform with conically pointed proboscis. Fam. Boegainvillide.

8. The broad body of the polyp well defined from the stem, and provided with a clavi-
form proboscis placed with a narrow basis on the whorl of the tentacles. Often two
kinds of nematocysts, large ones and small ones. Fam. Ludendride.

b. Colonies with calcareous skeleton and with two kinds of nematocysts, the large ones being

slenderly oval or nearly cylindric, frequently slightly curved. Fam. Stylasteride.

Il. Athecate Hydroids of the Northern Atlantic.

Section Capitata Kuhn.
Family Corynidae.

“Hydroids with fusiform or more cylindric polypes, whose oral portion is conically pointed.
The stinging capsules are large, oviform, or almost globular. All the tentacles of the polype are

capitate with the stinging cells mainly concentrated on the thickened distal portion. The structure

>*

12 HYDROIDA

of the tentacles is simple, with no central cavity, and with a thin supporting lamella without any
particular thickening. In the endoderm we must distinguish between an oral portion, abounding

in mucous gland cells, and the gastral portion proper. The colonies develop no calcareous skeleton”.

It is questionable, as is also pointed out by Kithn (1913), whether it is justifiable to maintain
the Corynidae and the Pennariidae as two distinct families. Stechow (1913) states that “das gleich-
zeitige Vorkommen geknOpfter und fadenformiger Tentakel ein vorziigliches Merkmal fiir das Bestim-
men ist”; simultaneously, however, he ranks the genera Acawlis and Clavatella with the Corynidae,
though, having tentacles both capitate and filiform, they should, from this main characteristic, be
reckoned among the Pennaritdae. Also as compared with the 7zézlaridae, the limitation of the Pexnari-
dae makes some difficulty. Thus Bonnevie (1899) e. g. classes //elerostephanus among the Tu-
bulariidae in spite of the fact that the species is provided with capitate distal tentacles. Stechow
(1913), on the other hand, as well as Broch (1911), ranks this genus with the Pennaridac. I regret
that I am in lack of material for a more thorough inquiry into the Pexnaridac; it is not unlikely
that the anatomical structure of the polypes might afford safer holds for the judging of this group of
hydroids than the merely outward morphological characters.

The Corynidae form a very central group, with which all the other groups of the section of
Capitata, stated by Kiihn, are likely to have originated. — At the first glance it may appear as if
one of the genera Monocoryne has got nematocysts heterogeneously developed, so as to show, be-
sides oviform or globular capsules, partly also long, narrowly oval ones. That this is not the case, is ascer-
tained by a careful study of material of Alonocoryne gigantea (Bonnevie) collected in the
Trondhjemsfjord. Partly all the nematocysts of this shape are discharged, and partly developmental
stages of other nematocysts than oviform ones are not traceable. It is, therefore, obvious that, in
being discharged, the oviform nematocysts assume a narrowly oval shape. The apparent dimorphism
of the nematocysts would otherwise have been greatly interesting as a connecting link with JZ7i0-
_ thela, and would have been likely to support the supposition of Bonnevie (1899) of the derivation of
the last-mentioned genus from the Corynidae through AZonocoryne. But as a matter of fact, the large
Monocoryne gigantea shows the anatomical structure of the true Coryuidae. Swenander (1903) mentions
that its tentacles are coalesced at the basis; this statement, however, only holds good for the ectoderm,
which in several places appears to be stratified; the endoderm, as far as the single tentacles are con-
cerned, continues, wholly surrounded by the ectoderm, to the supporting lamella. Aonocoryne gigantea
presents another peculiarity which the inquirers have hitherto obviously failed to notice; the indivi-
duals are hermaphrodite, in a most peculiar way. Not only we find in a single individual sheer female
and sheer male gonophores; but among these also occur several gonophores containing, besides large
ova, also sperms and spermatocytes of all stages. The gonophores of this species are reduced to
cryptomedusoids.

In the internal structure of the polype of the Corynzdae our attention is fixed on a great ac-
cumulation of mucous gland cells in the endoderm next to the orifice. Here are densely accumulated
a lot of cells, whose affinity with Delafield’s haematoxyline make them very conspicuous on material

well preserved. This concentrated glandular zone is found still more strongly marked in the dZyrvo-

HYDROIDA I2

thelidac, whereas in the 7wbularidac it has disappeared. It forms a striking contrast to the proboscis
of the HLudendriidae, the outer oral portion of which is more abounding in indifferent endodermal
cells and more nearly approaching the state of things in the Bougarnvilliidac, in which, however, also
the indifferent endodermal cells appear in larger numbers. As is mentioned beiore, this oral zone is
wanting both in the Clavidae and the Stylasteridae.

The Corynidac, like their near relations the A/yriothelidac, are distinguished by a vigorously
developed polype musculation, and in connection with this show an astonishing power of changing
appearance and volume. It is easy for them to swallow a comparatively large copepode, and in my
material I have found several shapeless-looking Coryze-polypes which were digesting rather large
crustaceans. Thus they are very greedy animals, frequently feeding on organisms larger than the
polype of normal size. Series of sections show how the food half dissolved also is led direct into the
gonophores and is absorbed by their endodermal spadix. The endodermal cells of the spadix then are
filled with some granulous contents, which are greedily absorbing and tenaciously keeping the haema-
toxyline of Delafield, while they are rather indifferent to both the haematoxyline of Bohmer and

to eosine. However, the cells also contain several eosinophile grains.

Gen. Coryne Gaertner.

“Corynidae forming colonies, with solitary capitate tentacles spread all over the hydranth. The
colony is formed by the ramification of an upright hydrocaulus, whose tubes do not communicate

through secondary canals. The gonophores are developed on the proximal portion of the polypes”.

Many investigators place the species productive of medusae in a separate genus, Syzecorye.
This criterion, however, is of merely biological nature, and thus of less importance to systematists.
And apart from this, it is evident that some species of Coryze produce more strongly reduced eume-
dusoids which are only quite exceptionally detached from the mother colony. The species have not
yet been sufficiently examined. Therefore, it is obvious that, for instance, the species Coryue Lovent
(M. Sars) must have been several times confounded with Coryne Sarsi (ovén). In the medusoid
gonophores of the former species the tentacles are wholly reduced, while Corywe Sarsz has complete
medusoid gonophores with tentacles. The opinion maintained by L. Agassiz (1860) and Hincks
(1868), based on the observations of L. Agassiz (l.c.) and Clark (1865), that some species of Coryne
at one time of their lives produce free-swimming medusae, at other times, on the contrary, sessile
eumedusoids, has not yet been refuted, but, quite the contrary, been strengthened by the observation
of a parallel condition of things in species of Campanularia (Giard 1899, Behner tg14). It is
not impossible that Coryne Sars: should be one of these species of Coryne. In Coryne Loveni the
eumedusoid gonophore has lost its tentacles, and at the same time the development of the generative
cells shows us that the gonophores are not here normally disengaged from the colony. Other species,
such as Coryne Hinckst Bonnevie and Coryne brevicornts Bonnevie, seem to have gonophores
somewhat more reduced, still, however, keeping the medusoid structure strongly defined. These
species, then, exhibit stages forming the transition to Coryne puszlla Gartner with its strongly

reduced styloid gonophores.

14 HYDROIDA

If we, therefore, like Kiihn (1913) and Stechow (1913), separate Syxcoryrve as a genus of its
own, there will be insurmountable difficulties about drawing the limits. If, as is done by Stechow,
the limit is drawn by the production of free-swimming medusae, Coryze Lovent must normally be
omitted from the genus Sywzcoryze, and a species such as Coryne Sarst will probably have to be reck-
oned sometimes among the Syzcoryne, at other times, on the contrary, among the Coryne. If, on
the other hand, we follow Kithn and draw the limits of genera between species with eumedusoid
gonophores and species having gonophores more strongly reduced, it may be greatly questionable
where, for instance, Corynze Hinckst and Coryne brevicornis ought in fact to be placed. In this case
as in others, the more species we learn to know more exactly, the more impossible it proves to draw
the limits of genera on the ground of gonophoral conditions. To this must be added that in all the
species of Coryze or Syncoryne the colonies and the polypes are so uniform as to their appearance,
that they cannot with certainty be identified to species or included under one or the other of the two
“genera”, if the gonophores are wanting or only little developed. It is, therefore, absurd to insist on
drawing an artificial and arbitrary line of distinction, founding on merely biological phenomena of

adaption.

Coryne Sarsii (Lovén) Johnston.

1835 Syacoryna Sarsii, lovén, Bidrag til Kannedomen af Slagterna Campanularia och Syncoryna
p. 275, pl. 8, fig. 1—6.
1847 Coryne Sars, Johnston. A History of the British Zoophytes, p. 43.

?i9tr Syzcoryne Sars, Semundsson, Bidrag til Kundskaben om de islandske Hydroider I, p. 72.

“The delicately constructed colonies attain to a height of up to 30 mm. The hydrocaulus is
wholly irregularly ramified with no distinct main stem; the branches form acute angles with the stem
or the main branch whence they proceed; both the stems and the branches are almost entirely
smooth with no rings nor wrinkles. The strongly contractile polype, when extended, attains to a
length of up to 1.5 mm., and is then almost wholly filiform; when contracted, it is oviform or nearly
globular. The numerous capitate tentacles are irregularly distributed over the polype.

The gonophores develop into medusae, which are likely to break away during the greater
part of the generative period of the polype; the medusa bud developes four tentacles. One or two,

more rarely three, gonophores occur simultaneously on the polype”.

Material:

Iceland, Reykjavik. Shallow water (associated with small JZyZclus).

In all probability, Sa mundsson (1902, 1911) is right in including these very delicately con-
structed colonies under Coryne Sarsii. The occurrence of the species is boreal. But the possibility that
the species is frequently confused with forms nearly related, as yet precludes certain decision as to its
distribution. Coryne Sarsi is recorded from the coasts of Norway, Bohuslin, Denmark, Helgoland,
Great Britain, Iceland, and Northern France. Hartlaub (1905 a) and Jaderholm (1903), though with

some doubt, refer some colonies from Tierra del Fuego and from Patagonia to the same species.

HYDROIDA 15

Coryne Loveni (M. Sars) Bonnevie.
1835 Syzcoryna ramosa, Loven, Bidrag til Kannedomen af Slagterna Campanularia och Syncoryna, p.
275, pl. 8, figs. 7—1O0.
1846 _ Lovent, M. Sars, Fauna littoralis Norvegiae, p. 2, footnote.
1899 Coryne Loveni, Bonnevie, Norske Nordhavs-Expedition, p. 14.

“The colonies are rather coarsely constructed and attain a height of up to 30 mm. The hydro-
caulus is wholly irregularly ramified and shows no distinct main stem. The branches proceed almost
rectangularly from the stem or the mother branch, but at once curve upwards, forming a very acute
angle or even a parallel with it. The hydrocaulus and the branches are almost entirely smooth, having

only here and there wrinkles slightly indicated. The strongly contractile polype, when extended,

caauarin: 2 O Os.17) EI Carsten eae aad boom mee eee ee, UCR eh 8) eee er ea 2000m.

Text-fig. A. The occurence of Coryne Loven in the Northern Atlantic (the hatched coastal Region denotes
a scattered occurence, the totally black parts indicate a common occurence)
attains to a length of nearly 2 mm., and then is slenderly fusiform or nearly cylindric; when contracted
it is oviform, oval, or almost globular. The numerous capitate tentacles are irregularly distributed
all over the polype.
The gonophores develop into eumedusoids, 1.5 mm. long, with no tentacles, normally not break-
ing away; they have four well-developed radial canals and a circular canal. Up to three gonophores

occur on the polype near its base”.

Material:
Greenland, Godthaab litoral (on Ascophyllum)

Norway, Bjarkéi, Lofoten litoral (on /2cotdeae)

16 HYDROIDA

Hartlaub (1907) informs us that in his aquaria he has observed a Syncoryne, whose gono-
phores are not set free, though being full-grown medusae with four tentacles well developed; the
generative products are developed in the sessile medusa, which is reduced after having performed her
generative task. Hartlaub refers this form to Coryne (Syncoryne) Lovent M. Sars. ‘This identifica-
tion however, cannot be right; most likely we have here rather in hand individuals of the Coryne
Sars during the part of the generative period when the medusae are not detached. Through Mr.
C. Dons, conservator at Tromsd6, I received a very copious material of Coryze Lovent from Bjarkéi,
where the species occurs in abundance on the /wcozdea in the tidal water region. The large number
of individuals examined have most frequently two, more rarely three gonophores, which are developed
into a complete medusa without any tentacles. The four radial canals end in a small enlargement,
which is the only indication of tentacles traceable. The species, accordingly, cannot be identical with
the form recorded by Hartlaub, but agrees very well with the description and the illustration given
by Lovén.

Coryne Loveni is earlier known only from the west coast of Scandinaviat. Jaderholm (1909,
taf. 1, fig. 7) gives an excellent drawing of the species collected from Bohuslan; elsewhere it is recorded
from the coast of Norway from Bergen as far as Lofoten, where its occurrence in the northern part
of its habitat is most numerous. Some colonies from Godthaab show us that Coryne Lovent must
also be added to the fauna of Greenland. The species is native to the boreal tidal water zone and

attains to its most luxuriant development in the passage to the regions of the Artic Ocean.

Coryne pusilla Gartner.
1774 Coryne pusilla, Gartner, in Pallas: Spicilegia zoologica vol. 1, fase. Io, pag. 40; pl. 4, fig. 8.
1893, Syncoryne mirabilis Levinsen, Meduser, Ctenophorer og Hydroider fra Grénlands Vestkyst, p. 150.
1902 Coryne vermicularis, C.fruticosa, Syncoryne eximia, Seemundsson, Bidrag til Kundskaben om de

islandske Hydroider, p. 50.

“The colonies are coarsely constructed, attaining a height of up to 4o mm. The hydrocaulus
is wholly irregularly branched, showing no distinct main stem; the irregularly curved branches are
everywhere densely wrinkled and form almost right angles with the hydrocaulus or with the
mother branch. The strongly contractile polyp, when extended, attains to a length of 2.5 mm., and
is then slender and narrowly fusiform or almost wholly cylindrical; when contracted, it is oviform or
oval. The numerous capitate tentacles are irregularly distributed over the polyp.

The gonophores are globose, showing a styloid structure. There occur 4—8 gonophores, irregu-

larly distributed over the proximal (basal) half of the polyp”.

Material:
The Faroe Islands.
Iceland: Grindavik. On littoral algae (labelled Coryne pusilla and C. fruticosa).
Reykjavik. On littoral algae (labelled Swcoryne eximia and Coryne vermicularis).
Greenland (labelled Syxcoryne mirabilis).

t Dr. P. L. Kramp kindly informs me, that Coryne Loven? is abundant in the Little Belt.

HYDROIDA 17

A closer investigation of the living polyps and of their conditions very soon shows us that the
appearance of the polyp is varying very strongly according to its state of contraction. Now it is
stretched at length, assuming approximately the shape of a thin worm, now it is again contracted to
a short, thick lump, very nearly approaching the globular shape. Sometimes the polyp is at the widest
at the base; sometimes it is contracted in this part, so that the largest width appears farther out.
The study of the live polyps thus, in this case as in many others, shows us that many characters
which have been turned to account as criteria of species with the Coelenterata, may be of most doubt-
ful value or even of no importance whatever to classification. In the first place, of course, this is appli-
cable to the various states of contraction, which, in Corynxe pusilla, have even led to subdivision into
several species. Jaderholm (1909) thus, on account of difference of shape of the polyp, still

distinguishes Coryne pusilla and Coryne vermicularis Hincks; as, however, all other characters wholly

200 Mm. IC NE CES Ste - tooom. a —.—..2000m

Text-fig. B. The distribution of Coryne pusilla in the Northern Atlantic.

agree, and the differences put to account as specific characters fall far within the limits of the polyp
movements described above from observation of living individuals, the separation into species cannot
be recognized; Coryne vermicularis forms a synonym of Coryne pustl/a and, in fact, only represents a
phase of the movement of the polyps.

Coryne pusilla has previously been recorded from the north of France, from Great Britain and
Ireland, from Helgoland, from Denmark, from Bohuslin, from the west coast of Norway, from the
‘aroe Islands, and from Iceland (Reykjavik). In my material there also occurs a colony marked
“Greenland?”, wrongly determined as Syxcoryne mirabilis Agass; the species thus seems to belong to
the fauna of Greenland, but particulars are still missing. The rather numerous Icelandic colonies of

the species are all derived from the south-western point of the island. The species, accordingly, must

The Ingolf-Expedition. V. 6. 3

8 HYDROIDA
be characterized as southern boreal; it mainly occurs along the coasts of the North Sea and round
the British Isles; how far it advances to the north on the coast of Norway, we do not as yet know

with certainty; but a any rate it does not push forward as far as into the Arctic seas.

Coryne sp. aff. Hincksi Bonnevie.
Material:

“Ingolf” St. 44. 61°42’ Lat. N., 9°36’ Long. W., 545 met. 4.8°.

A small colony of young individuals of a species of Coryxe is attached to the stalk of a Zi-
bularia sp. The hydrocaulus is irregularly wrinkled and attains a height of up to 6 mm. with polyps
1—2 mm. long. There occur 4—8 small, apparently medusoid, gonophores at the base of the polyp
closely below the tentacles. The tentacles are short. The stolon of the colony is reptant, the stalks
of the polyp are unbranched. On account of the bad state of preservation it is impossible to furnish
a proper design of the individuals.

It is possible that the individuals belong to the species Coryne Hinckst Bonnevie, which

has previously been recorded only from a depth of 100 fathoms near Hammerfest (Bonnevie 18g9).

Family Myriothelidae.

“Large solitary hydroid polyps with stratified ectoderm, in which occur two kinds of nemato-
cysts. Besides the typical oviform nematocysts of Cafzfata are found in somewhat smaller numbers
narrowly oval or nearly cylindrical, rather large nematocysts which are especially frequently occur-
ring in the ectoderm of the gonophores. The tentacles are capitate with a central cavity which does
not communicate with the gastral cavity of the polyp, and which is distally broader. The vigorously
developed distal portion of the tentacles is shored up by a particularly developed portion of the supp-
orting lamella, here showing a fibrillary structure with fibres radiarily arranged. The supporting
lamella is vigorously developed in the wall of the polyp and provided with bilamellae. The endoderm
exhibits a dense circle of mucous glands at the mouth of the animal. No calcareous skeleton is

developed”.

The Atyriothelidae seem to be nearly related to the Corynidae, and also to the ALleporidac,
which latter form calcareous skeletons. The last mentioned family presents in its dimorphically
developed nematocysts a strong resemblance to the AZyrzothelidac. However, only a character as the
peculiarly developed supporting lamella in the thickened distal portion of the tentacles, as well as
the dimorphic development of the nematocysts, justifies the distinction of the J/yriothelidae as a patti-
cular family beside the Corynidae. Already Bonnevie (1899) has pointed out the near rela-
tion between Myrzothelidae and Corynidae and the bridge between them suggested by the species J/o-
nocoryne gigantea (Bonnevie). The arrangement by groups of the tentacles and the attachment of
the gonophores to these groups are very likely to form the base of the development of the blasto-

styles of AZyriothela, But on account of the peculiar direction in which the structure of the tentacles

HYDROIDA 19

of the Afyriothelidae has developed, we cannot subscribe to the view of Ktihn (1913), reducing the two
families into one. The anatomical structure of the polyps of the two groups differs too much, and to
this difference must be attached a greater importance than the investigators have hitherto been inclined
to do; anatomically the difference between the groups is too great to allow their amalgamation, in
spite of the agreement of the two families as to the endodermal mucous gland portion near the ori-
fice of the polyp.

Hitherto only one genus has been recorded of Myriothelidae.

Gen. Myriothela M. Sars.

“The large solitary polyps have only exceptionally slight indications of hydrocaulus; in general
the base of the polyp is truncate or pointed and provided with rhizoids or filaments of adhesion,
which are in fact transformed tentacles. Both the ectoderm and the endoderm are stratified. The
tentacles are capitate and are irregularly distributed over the polyp and the blastostyles. The gono-
phores are developed on small polyp-like blastostyles attached to the inferior half of the polyp; the

blastostyles bear tentacles on their distal portion”.

The genus AZyriothela is recorded from the northern seas and from the Antarctic Ocean. The
c=)
spread and rare occurrence of the individuals prevents us from deciding whether the genus is in fact

bipolar, as the finds hitherto recorded seem to indicate.

Myriothela phrygia (Fabricius) M. Sars.
1780 Lucernaria phrygia Fabricius, Fauna Groenlandica, Nr. 333, p. 343.
1851 ALyriothela arctica M. Sars, Beretning om en zoologisk Reise, p. 134.

1873 — phrygia G.O. Sars, Bidrag til Kundskab om Norges Hydroider, p. 130.

“The capitate or almost cylindrical polyp extended reaches a length of about 4oo mm. The
inferior termination of the polyp is truncate, and it is attached to the substratum by tentacle-like fila-
ments of adhesion. Above the portion wearing blastostyles it is studded with strong capitate tentacles;
on the other hand tentacles are wanting on the surface of the polyp between the blastostyles.

The cryptomedusoid gonophores are developed on small polyp-like blastostyles, attached to the
inferior portion of the polyp and wearing capitate tentacles on their outward parts. The female blasto-
style has only one or two fully-developed gonophores at the same time, while the male blastostyles

wear numerous gonophores”.

Material:
“Ingolf’ St. 117. 69°13’ N., 8°23’ W., depth 1003 fathoms, + 1° C.
— St. 125. 68°08’ N., 16°08’W., — 729 — + 08°C.

Myriothela phrygia Nas an enermous faculty for extension and contraction, and it is likely to
share this faculty with its nearest relatives. A specimen I had the opportunity of observing when it
was brought up by the trawl in the Trondhjemfjord, had stretched its distal portion wearing tentacles

so strongly that the animal was as thin as a thread and measured up to 30 cm. in length; but as

re)

20 HYDROIDA

soon as it was irritated by the preservation fluid, it contracted to a length of only 9 cm., and simultan-
ously the diameter of the distal portion of the polyp increased to the measure of 2—3 mm. This
observation shows how little importance is, in fact, to be attached to the absolute measures of the
polyp in the limitation of the species of AZyriothela. While the individuals from st. 117 wholly agree
with the earlier descriptions and drawings of the species, the defective specimen from st. 125 (tab. I,
fig. 8) at the first glance differs greatly. The broad, longitudinally strongly contracted basal portion
is studded with blastostyles in a narrow belt, above which the polyp tapers rapidly so as to assume
a conical appearance fairly reminding of the drawing by Bonnevie of ALyriothela mitra (1899, tab. IV,

fig. 3). However, a closer examination shows that the distal portion of the polyp has been torn off,

200M moe wee— OOO RR -.t000mM. arn sen SOLE

Text-fig. C. Localities of Myvriothela phrygia in the Northern Atlantic.

and as its trunk above the blastostyles is studded with capitate tentacles, while the polyps of the
species mentioned have no tentacles at all, a mistake of identity is out of the question.

Myriothela phrygia is an arctic deep-sea form, mainly occurring in the icy water at the bottom
of the northern seas. It is recorded from Taimyr (J4derholm 1908), from the north of Norway, and
from the depths of the ocean between Spitzbergen and Greenland (Bonnevie 1899), besides from the
localities laid down in the map subjoined (Text-fig. C). The original description has been given on
specimens from Greenland, from where, however, we still lack particulars as to localities. “Ingolf”
now adds two new finds in the waters of the Arctic Sea between Iceland and Jan Mayen. On the
whole, the occurrence of the species is scattered; most of the finds are situated in high-arctic regions,
and here the species is seen to occur even at so small a depth as between 12.8 and 14.6 m (J ader-

holm 1908). Therefore, two localities are, indeed, apt to give surprise. One of these localities is recorded

HYDROIDA 21

from the “Michael Sars” 1902, when the species was found in the warm Atlantic waters to the south of the
Wyville-Thomson-Ridge (Broch 1903). There is in this case a possibility that the animal has been carried
with Arctic currents from northern regions; if so, the currents have conveyed the animal at an early
period of life to the new locality, where it has been able to subsist and develop further. The other
locality, in the Trondhjemfjord was previously recorded, and the Trondhjem Museum was in possession
of a defective specimen which was said to have been taken in the fjord; but particulars were wanting
till the researches of the fjord in 1911 brought to light, from the depth of 200 m., near Tautra, and
thus in the midst of the Atlantic water layers of the fjord, a well developed female polyp. This find
gives the more surprise, because there is left no opening for the possibility that the specimen should
have been carried to this place from Arctic water layers. Like other Arctic hydroids, such as
Tubularia regalis Boeck, Corymorpha groenlandica (Allman), and Stegopoma plicatile (G.O. Sars),
Myriothela phrygia thus thrives very well in the region of the Trondhjemfjord which is otherwise
characterized by Atlantic Zofhohelia-reefs. This cannot, however, be turned to account as a proof
against the Arctic character of the species; in the Trondhjemfjord all these species must be looked

on as Arctic relicts.

Family Tubulariidae.

“Hydroids forming colonies, or solitary, with large oviform or globose nematocysts in the ecto-
derm. The tentacles of the full-grown polyp are filiform and simply constructed with no central cavity;
they are arranged in two main circles, a proximal whorl round the broad basal portion of the polyp
and a distal whorl round the mouth. The basal whorl of tentacles is supported by a ring-shaped
mesogloeal cushion round the basal portion of the polyp. The polyps are radially symmetrical. The

supporting lamella shows a very simple structure”.

Most authors refer to this family also Branchiocerianthus, which I reckon as the type of a family
of its own, the Branchiocerianthidae. This family is distinguished from the Z2dzdaritdae partly by bilaterally
symmetrical polyps, partly by the peculiar anatomical structure of the polyps. In fact, the structure of the
polyps of the Branchiocerianthidae differs greatly from that of all other hydroids (comp. Stech ow 1909).
There occurs a supporting lamella of complicated structure, and the polyp is provided with numerous,
prominent radial canals. They are distinguished from the Z2ée/ar7dae also in their inner anatomy by almost
lacking any trace of mesogloeal tissue at the base of the proximal whorl of tentacles, owing to the
radial canals. These points of difference are, indeed, of such importance that they fully justify the sepa-
ration of Branchiocerianthus into a family of its own, the Branchiocerianthidae beside the Tubulariudae.

Kiihn (1913) divides the Zadulariidac into two subfamilies, 7dulariinae and Corymorphinae.
The former he defines by the characters “Koloniebildend, Periderm gut entwickelt”, while the latter
is defined as “Solitir, Periderm hiutig oder riickgebildet, Wurzelhaare”. To this is to be observed that
a species as 7ubularia cornucopia Bonnevie is a typical Zwébularia in spite of its forming no colonies.
The filamentary appendages of Corymorpha must be compared with similar phenomena in J/yriothe/la,
some species of which have rhizoids, while others such as A/yriothela Cockst (Vigurs), attach thems-

elves by a plateformed perisarc; when this is considered as nothing else or no more than a criterion

22 HYDROIDA

of species with AZyriothela, there tells indeed little in favour of raising it to a distinguishing mark
between two subfamilies of the Zzdzzlartidae. As far as finally the development of the periderm is
concerned, this is a gradual character showing many transitions, to which no importance can be

attached as a distinguishing mark between two subfamilies.

Gen. Tubularia Linné.

“Hydroids most frequently forming colonies, the hydrocaulus being surrounded by a stiff and
chitinous perisarc. The polyps are radially symmetrical, having two main circles of tentacles, a proximal
(basal) whorl of long tentacles leaning on a mesogloeal ring in the trunk of the polyp, and a distal
whorl with short tentacles round the mouth. The tentacles are also in the actinula filiform! The gono-
phores are generally borne on blastostyles; the gonangia spring from the trunk of the polyp between

the two whorls of the tentacles”.

The gonophores are, in this genus as in most other genera, sometimes medusoid, sometimes
more or less reduced. The species producing free medusae have been grouped by many authors as a
genus of their own, //ydocodon. In this case as in others, the question then arises where the line is to
be drawn. While in species as 7udularia pulcher (Seemundsson) the medusa breaks away, the fully
developed medusoid gonophore in Zwzdularia regalis Boeck, as far as is known to us, never voluntar-
ily relinquishes its sessile existence. If we follow Kiihn (1913), as might seem right, we get into a
dilemma, having to refer the female of 7adbelaria regalis to Hybocodon, while the male, having crypto-
medusoid gonophores (Broch rgr5), must remain in the genus Zwéwlarza. Only this should be suffi-
cient to show the error of turning the organisation of the gonophores to account as fundamentum
divisionis. No doubt, it is wrong to set up /yéocodon as a particular genus of hydroids, and the same
is certainly the case with the genus Az/iscus set up by Seemundsson (1899), the medusae of which
as we are going to see, are scarcely particularly distinguished as compared to the other AWydbocodon-
medusae.

Tubularia pulcher (Szemundsson).

1899 Aaliscus pulcher Semundsson, Zoologiske Meddelelser fra Island, p. 425, Tab. IV.

“Colonies, the hydrocauli of which are up to 50 mm. long, unbranched, and separated down to
the reptant hydrorhiza. The stalk is covered with a brown perisarc, which is thick at the base, but
upwards against the polyp narrowing periodically and at distinct intervals, so that the stalk gets an
appearance approximately articulate; the spaces between the transverse striae, brought about in this
way, attain their greatest length in the middle part of the stalk, being here 13 mm. long. The upper
portion of the stalk is provided with a thin perisarc, widening funnel-shapedly into a thin collar
under the polyp. The polyp is fitted out with a basal circle of 24—30 tentacles, about 5 mm. long;
the distal tentacles, about 30, are placed, densely crowded, in a narrow belt, consisting of several rows,
round the orifice, and attain a length of a little more than 1 mm.

The gonophores develop into free //ydocodon-medusae with gemmation on the bulb of the

« The tentacles of the actinula may be swollen at their tips (comp. Allman 1872) but never show the dense accumula-
tion of stinging cells here. which is so characteristic in the truly capitate tentacles of the section Cafvtata.

HYDROIDA 23

large tentacle; there are four radial canals. The bell exhibits five exumbrellary stinging cell stripes.

The gonophores are developed on eight blastostyles faintly branched, a little more than 1 mm. long”.

Material:

Iceland, Reykjavik. Near the shore (1 specimen).

The specimen in hand is one of the original specimens investigated by Samundsson (1899).
It is an individual with hydrocaulus 30 mm. high. The polyp is fitted out with 25 proximal tentacles,

gonophores

2

5 min. long, and 8 blastostyles a little branched, about 1 mm. long. A closer inquiry of the
gives a picture somewhat different from that drawn from the explanation of Semundsson. In the
first place the umbrella of the medusa is not quite symmetrical, but somewhat oblique, as in //yboco-
don prolifer 1, Agassiz. At first only one tentacle, not two, is developed on the large tentacle bulb
(Tab. II, fig. 16); the “corpora acuminata et duo ovata”, mentioned by Szemundsson as springing
from the tentacle bulb, are all gems of medusae; none of them can be made out as “initium tentacu-
lorum novorum” belonging to the original medusa. Wherever at the first glance two tentacles seem
to occur on the bulb, a closer research will show that one of them in fact belongs to the bud of a
new medusa on the bulb of the gonophore. Therefore, we have to concur in the opinion of Hart-
laub (1907) and subscribe to his explanation of the apparent occurrence of two tentacles with //yéo-
codon prolifer as satisfactory for the species in hand, that “bei der Knospung von Hybocodon der Ten-
takel in der Entwickelung stark voraneilt und schon fertig sein kann, wenn der dazu gehdrige Me-
dusenkérper noch nicht deutlich in die Erscheinung getreten ist”.

The conditions of gonophores described show a much nearer relationship to Zzdularia (f/ybo-
codon) Christinae Hartlaub (= Tubularia prolifer Bonnevie 1899). Hartlaub’s drawing of //ybo-
codon Christinae (1907, fig. 98) is, according to the statements cited, easily recoucilable to the figure a
little more skeletonlike given by Seemundsson (1899, tab. IV, fig. 3). Nor is the difference between
the polyps very great; Bounevie (1899} states for her specimen 14 proximal tentacles, about 10 mm.
long, while the species stated by Samundsson is said to have 24—30. It is a matter of regret that
we only know the length of the proximal tentacles of the specimen in hand. But on account of the
great contractility of the tentacles, no particular systematical importance can be attached to their
length, and as far as the difference of numbers of the proximal tentacles is concerned, we see in other
Tubularidae within easy reach such a variety that the difference quoted by itself cannot justify any se-
paration of species. When 7udularia Christinae is nevertheless maintained as a separate species beside
Tubularia pulcher, it is in the first place owing to the express declaration of Bonnevie (1899) that
her specimen has no collar under the hydranth; such a collar is, on the other hand,‘strongly developed
in Zubularia pulcher, though at the first glance it may seem very little distinctive on material preserved."

Hartlaub (1907) holds that the medusa is identical with the medusa drawn by Steenstrup
(1842), Coryne fritillaria, and much is speaking in favour of the correctness of this supposition. On the
other hand, the polyp described by Steenstrup, in the same place and by the same name, cannot
be identified. It may be that it really is a Coryne,; some features are even suggestive of Coryne Lo-
vent M. Sars; but the only thing the drawing shows us with full certainty, is that the polyp is no

1 The original specimen of Bonnevies Zubularia prolifer was wanting in the museum of the Kristiania university.

24 HYDROIDA
Tubularia, and that its medusoid gonophores, if they are rightly perceived, cannot develop into medusae
of the Hybocodon type.

The only locality from which Zxdularia pulcher is recorded with certainty, is the shore near

Reykjavik, Iceland, where it has been found only once.

Tubularia indivisa Linne.
1758 Tubularia indivisa Linné, Systema Naturae, Ed. 10, p. 803.

1899 ~- obliqua +- T.indivisa Bonnevie, Norske Nordhavs-Expedition, p. 24.

“Colonies, whose long dark brown-coloured hydrocauli are, in the lower part, twisted together.
The stems are covered with a vigorous perisarc, but show no rings nor wrinkles. No collar is formed
below the polyp. The polyp has a basal whorl of 20 to 30 tentacles up to 20 mm. long; the distal
tentacles are up to 3 mm. long and densely crowded round the orifice in a whorl consisting of
several rows.

The female gonophores are eumedusoid with four rudimentary radial canals, one of which
(the shortest) is often slightly indicated even in the gonophore fully developed. The gonophore
has, near the apex, a tentacle-like bulging, obliquely situated. The male gonophores are crypto-
medusoid and almost wholly globular, not oval. The gonophores are born upon up to Io blasto-
styles, which attain a length of 10 mm. ‘The actinula-larvae, when set free, wear filiform

tentacles”.

Material:
“Ingolf” St. 31, 66°35’ N., 55°54’ W.; depth 88 metres 1,6° C. (Davis’s Straits).
— St. 87, 65°02’, N., 23°56’, W.; depth 110 metres (West-Iceland).

Greenland: Davis’s Strait (without further data).

— Egede’s Minde( — — —).
Iceland: Brede Bugt 65°12’ N., 23°28’ W., depth 36 fathoms.
— Grindavik littoral.

— Skagestrand depth 60 fathoms.
— Vestmannod littoral.
The Faroe Islands (without further data).

The North Sea: the West side of large Fishing bank 57°7’N., 2°40’ E., depth 37 fathoms.

Swenander (1903) has pointed out that T'belaria obliqua Bonne vie (1899) is based on female
individuals of 7wdularia indivisa; thus in the very external characters of the gonophores this species
presents a peculiar sexual dimorphism, and inquiries into the conditions of the gonophores (Broch
1915) have made good that this sexual dimorphism is a radical one, the female gonophores being
eumedusoid, the male ones on the contrary cryptomedusoid. — Zwébzlaria indivisa is very easily con-
founded with the following species, Zadularia regalis, particularly when only male individuals are in
hand for examination. In this case only the somewhat different shape of the gonophores makes it

possible to refer with certainty the individuals to one species or the other, the male gonophore of

HYDROIDA

N
1

Tubularia indivisa being globular, and accordingly broadly rounded in the distal part, while that of
Tubularia regalis is oval and showing au attempt to be pointed in the distal part.

Tubularia indivisa has a very wide distribution. Its main occurrence in the boreal seas is bound
to the middle and deeper parts of the littoral region and to the upper part of the deep sea region.
From the cold area we find the species but once recorded, by Grieg (1914). After the examination
of his specimens I cannot confirm this record; the specimens consisting only of hydrocauli without
polyps, more probably belong to another species of Zwéw/aria inhabiting the deep sea.

To judge from literature, Zédelaria indivisa penetrates rather far into the shallower parts of
the Arctic regions, where it is recorded even from the New Siberia Islands (J iderholm 1908). How-

ever, as appears from what is stated above, there is a possibility that some of the Arctic individuals

sovvsscessisescsces 200 MM, = amma maa 600m. twee 1000 M.

esate eae, 2 OGOIM.
Text-fig. D. The distribution of Zwdularia indivisa in the Northern Atlantic.

are in fact to be referred to 7wdelaria regalis. — The species also penetrates far towards the south.
It is recorded by Fewkes (1881) even from the Caribbean Sea, by Allman (1877) from between Cuba
and Florida, and by Billard (1906) from the west coast of Africa. As Zzbelaria indivisa is recorded
at the same time both from the East and the West coast of North America, it must be characterized

as a circumpolar or rather “circumboreal” (Nordgaard 1912) species.

Tubularia regalis Boeck.
1860 Tubularia regalis Boeck, Videnskabsselskabets Forhandlinger for 1859.
1899 -- — + TZvariabilis Bonnevie, Norske Nordhavs-Expedition, p. 24.
Colonies whose long, dark-brown-coloured hydrocauli are in the lower parts twisted together.
The stem is covered with a vigorous periderm, but shows no rings nor wrinkles. No collar is formed

The Ingolf-Expedition. V. 6. |

26 HYDROIDA

below the polyp. The polyp wears a basal whorl of 20—35 tentacles up to 4o mm. long; the distal
tentacles, up to 3 mm. long, are densely crowded round the orifice in a whorl consisting of several rows.

The female gonophores are eumedusoid with 3—6 external longitudinal ribs and as many
corresponding radial canals. The male gonophores are cryptomedusoid and oval, often with an attempt
to be pointed in the distal part. The gonophores are born upon up to 20 blastostyles, which attain a

length of 35 mm. The actinula larvae, when deliberated, wear filiform tentacles.

Material:

Between the Faroe Islands and the Shetlands, depth 505 fathoms.

Tubularia regalis presents so many points of resemblance to 7wdelaria indivisa that the risk of

confounding the two species is very easily incurred. As a general rule, the full-grown polyps of 72-

cotenbaganonensIaS¢ 200 m. eo rs as ewe = OOO) IM, tame ee 1000 M~. seroma ea OO

Text-fig. E. The occurence of Zudularia regalis in the Northern Atlantic.

bularia regalis are larger than those of Zudbeularia indivisa. But this is not the case in younger
individuals of Z2bularia regalis, in which consequently the only certain distinguishing marks are pre-
sented by the gonophores. The gonophores, indeed, are typical enough in the female individuals, but
are not very conspicuous in the male ones, especially at earlier stages. The male gonophores of 7Z7-
bularia regalis are oval, while those of 7udbularia tndivisa are globular. It is evident from the diag-
nosis of the species, that also 7wbeularia regals presents a strong sexual dimorphism. ‘The first who
got aware of this fact, was Swenander (1903), who accordingly pointed out that the female had been
described as a different species Zubularia variabilis Bonnevie.

Tubularia regalis is a form of true Arctic character, particularly occurring in the deeper

parts of the cold area. In the seas far towards the north it rises to shallower parts, and it is, for instance,

HYDROIDA 27
recorded from Spitzbergen at the depth of only 38 m. (Broch 1909). Evidence of its occurrence
in the Kara Sea is still wanting. From this locality a specimen is in hand, determined by Bergh
(1887) as Zubularia regalis. As a matter of fact, the specimen is a Corymorpha, probably a Cory-
morpha glacialis M. Sars. — A remarkable exception to the habitat stated is formed by the frequent
occurrence of the species in the Trondhjem Fjord, where it is found in abundance on the Lophohelia-
reefs. In spite of the luxuriant development which it attains in the Trondhjem Fjord, it must probably,
like Corymorpha groenlandica (Allman), Myriothela phrygia (Fabricius), and Stegopoma plicatile

(G. O. Sars), be accounted for as an arctic relict in this locality.

Tubularia larynx Ellis et Solander.
1786 Tubularia larynx, Ellis et Solander, The Natural History of Many Curious and Uncommon
Zoophytes, p. 31.
1864 —- humilis, Allman, Notes on Hydroida, p. 57 and 60.

Colonies whose long polyp stems, generally unbranched and irregularly curved, are separated
quite down to the tangled network of basal tubes. The stems are covered with a fairly vigorous, but
colourless perisarc, which is irregularly wrinkled or more rarely quite smooth. The polyp wears a
basal whorl of up to 25 tentacles, attaining a length of 8 mm.; the numerous distal tentacies, 2 or 3
mim. long, are densely crowded round the orifice in a whorl consisting of several rows.

The gonophores are eumedusoid, without radial canals, but with a rudimentary circular canal;
they are most frequently provided with three rudimentary tentacles. The gonophores are supported by
6—12 short blastostyles, which may be erect or hanging. The actinula larvae, when deliberated, show

filiform tentacles.

Material:

Iceland: Reykjavik.
GASES EYE cis We ota dey aia hE 5 oe nse Taucile Bie Page yen arecele SUPRA o Chee ane aye depth 4 fath.
Reetlavakes «pcieepam eggs isiici sis ore, siaiecavahege pe dualslerandueeees Slams aisbaapagene ee came at I5—16 -
Haxehmots three: miles ING7 by ke ellaivilke tna cite io cus sities teens ee _- 195 —
Ol delanel Ord: vate vac aes cotati goatee worn Reap oe a lotena sad Soars ab noeonemt -- 25 -—
Sty Kkisholmye ns quscictosnsneaelet cat ony Ge NONE S ayefaer ecoermes cutjans ghelerst onto — 20-30 —
SEG 1h Avs tn eh ctn, Sate eae caves Ne, nine thaectacatn SaNae NEES sae cist dietotenahe altel = 40 m
MGS Eta iOS ATS! es ee mates oven cin el clase sertooeia piel atthent a wisv overs «spoushe oie oaks) ¢ ~- 28 fath.

ANOS VECO DIE Nehss Teh saferdeld oy Ay eloes G ee Oeke bon ee owe Shae Ch omeae suede — 16—23

MLSE sNOL eh Sear OOS aha Ne mrCO LE a dictencbererersn teh wvsas ein. cian sithafehceiae saisleryers aeons -- 50 —

The synonymy of the varying species has been thoroughly accounted for by Fenchel (1905).
He points out that, as is also maintained by Bonnevie (1899) and by Swenander (1903), Z2dezlarta
coronata Abildgaard must be subsumed under 7zdelaria larynx. On the other hand, it is not plainly
seen whether he regards Zubeélaria humilis Allman to be a peculiar species. On a closer exami-
nation, indeed, the characters pointed out by Bonnevie (1899) as distinguishing marks, prove to
be of no particular systematic importance. The wrinkling of the stem is strongly varying from

HYDROIDA

iS)
(ee)

one individual to another in a larger colony, and individuals with quite smooth stems are not seldom
observed in colonies which are otherwise typical Zdelaria larynx. ‘The dimensions of Z2dbelaria humels
wholly agree with those of young colonies of Zudularta larynx, and the numbers stated as characteristics
stand far within the range of variability known in this species. Then only remains the condition of
the blastostyles, which should be erect in Zudelaria humilis, but hanging in 7ubwlarta larynx. An
examination, however, of living material will show that only in rare cases the blastostyles of 72dzlaria
larynx can be described as hanging (comp. Broch igri); on the contrary they are generally borne in a
rather erect position, particularly when not yet very large. Thus also this criterion proves to fail,
and consequently we are forced to consider Zaéelaria humilis as a synonyme of Tubuélaria larynx.

Tubularia larynx is an entirely boreal species, which has its main occurrence in the zone of the

acottaoesaAsooT 200 mM. Sse soo UUOtn Seep CEB peeaisiecssoetrece te OOOITT:

Text-fig. F. The distribution of Tudularia larynx in the Northern Atlantic.

laminaria and the red algae. Towards the south it enters into the Mediterranean, and towards the
north it penetrates as far as Nova Zembla, and seems still to occur at Spitzbergen. On the south-
western coasts of Iceland it is very frequent, and it is also found on the east coast of North America,

It is to be wondered that the species has not yet been met with at Greenland.

Tubularia sp. indet.
Stems of Zudelaria of the type indivisa-regalis are in hand from the following localities:
“Ingolf”? St. 8 63°56’ N., 24°40’ W., depth 136 fathoms, + 6°o C.
AGS Wigs, HOS TO" Parise ROR se ECG OZR Ne Mar 10h
=H eB01 OlsSOe =) 50227 — 1435 — + 1°5 -

HYDROIDA 29

“Ingolf’ St. 4o. 62°00’ N., 21°36’ W., depth 845 fathoms, + 3°3 C.
Pp)

— - 86. 65°03'6 - 23°47'6 - —- 7 —

—~ - 87. 65°03'2 - 23°56'2 - — m0 — ?

— - 106. 65°34’ - 8°54’ - — 447 — =, O76. G.
— - 127. 66°33' - 20°05' - — 44 — + 5°6 -
— - 143. 62°58’ - 7°09! - -—— 388 — sop Oi ae

Of a type like that of Zudbularia cornucopia Bonnevie from the localities:
“Ingolf’ St. 11. 64°34’ N., 31°12’ W., depth 1300 fathoms, + 1°6 C.

a a 18. 61°44! Z 30°20' _ —_ 1135 = ={e 2°6 2

Gen. Corymorpha M. Sars.

Solitary hydroids, whose contractile hydrocaulus is surrounded by a flexible, thin, and membran-
aceous perisare. The hydrocaulus is attached to the substratum by numerous rhizoids. The structure
of the polyp is radially symmetrical with two main whorls of tentacles, a proximal or basal whorl
of long tentacles supported by a mesogloeal ring in the polyp body, and a distal whorl of short ten-
tacles round the orifice. In the full-grown polyp all the tentacles are filiform; in the actinula
larva at any rate the distal (oral) tentacles may be capitate. The gonophores are generally supported

by blastostyles; the gonangia arise from the body of the polyp between the tentacle whorls.

As early as 1909 I stated this limitation of the genus, grouping at the same time the species,
on the ground of gonophoral matters, in four subgenera. However, I suggested that, as to the rela-
tions between the two subgenera Monocaulus and Lampra, a closer inquiry was wanting. As a matter
of fact, one of the species stated by Allman (1876) Monocaulus groenlandica really proves to be
identical with two of the species of Lampra stated by Bonnevie (1899). Also the other northern spe-
cies of Monocaulus has met a peculiar fate, being first ranked by Allman (1872) within his genus as
Monocaulus glacial’s (M. Sars), and afterwards (1876), after the examination of some specimens from
the museum of Copenhagen, described as a new species, Amalthaeca tslandica Allman.

These matters, indeed, throw a glaring light on the unmaintainability of the subdivision into
so-called “genera” to which Corymorpha has been the subject. At the first glance it is a matter of sur-
ptise that Stechow (1913) still tries to maintain the old genera. Indeed, in zoology more considera-
tion must be given to the observations made on living individuals than has hitherto been done. Thus
the two main criteria turned to account by Stechow (1912) for the purpose of distinguishing Cory-
morpha Sarsti Steenstrup (1854) and Corymorpha vardéensis oman (1889) testify to the fact that
matters of contraction are still allowed to play a prominent part as to the limitation of species. By
the observation of a living Corymorpha it will soon be ascertained that, by extension and contraction
of the lower parts of the polyp and of the upper sections of the stem, the same polyp will show now
a more emphatic distinction from its stem, now a smoother transition into it. The points of difference de-
lineated by Stechow (1912, Taf. 12, Fig. 2 and 3) are, in this respect, not so great as those which

may be observed in a single individual while alive. The other main character, that the spadix of the

30 HYDROIDA

gonophore of Corymorpha Sarsii is “fast immer” projecting from the umbrellar cavity, while this is
“fast nie” the case with Corymorpha vardéensis, is in the first place very vague, and secondly depend-
ent partly on the various contraction of the umbrella, partly on the sex and the degree of maturity
of the gonophore. On the whole there can be no doubt that the description of Corymorpha vardéensis
is based on an individual of Corymorpha Sarsi.

I have entered on this subject because Stechow (1912, 1913) puts together the species menti-
oned into a genus of their own, malthaca. The genus was first established by O. Schmidt (1854) for the
species Amalthaeca uvifera O. Schmidt, which is likely to be identical with Corymorpha Sars. It em-
braces the species of Corymorpfha whose gonophores develop into complete medusae, but, after all, not
breaking away, whereas the species whose medusae are normally breaking away, are gathered in the
genus more narrowly limited, Corymorpha. It is evident,however, that the medusa of Amalthaca excep-
tionally breaks away and then leads a wretched life, unfit as it is for free existence on account of
possessing a too small umbrella, the greater part of which is, into the bargain, occupied by the enormous
spadix with mature generative cells. The medusa strongly reduced, further, shows so near a rela-
tionship to the medusa of Corymorpha nutans M. Sars that a systematist of medusae so skilful and
discerning as Hartlaub (1907) decides on only placing it in a subgenus of the medusoid genus
Corymorpha. he classification afterwards maintained by Mayer (1910), who distinguishes the two
groups of medusae as peculiar genera and even places them in quite different places in his syn-
opsis, as Amalthaca and Steenstrupia, only proves that he has failed to notice the excellent drawing
by M. Sars (1877), which shows us in fact, that the female gonophore, when fully developed, is often
an entirely typical S¢eenstrupia, though one of the main tentacles is not quite so large as in Cory-
morpha nutans. The figures delineated by Sars wholly agree with the facts observed in living
individuals, and make good the correctness of Hartlaub’s view of division, giving the right place
to affinity and biology. But where is then the fundamentum divisionis adaptable for the purpose of
classifying the Corymorpha-like species of polyps into separate genera?

From Amalthaea to Monocaulus glacialis there is, indeed, a very short step; all the difference,
as a matter of fact, is to be found in the gonophore, also here eumedusoid, being even somewhat more
reduced, as the tentacles, the special organs of the umbrellar margin, are entirely wanting. The con-
formity of the polyps is obvious; the gonophores of both species are eumedusoid and normally sessile;
the difference is accordingly too little for a separation of genera.

Then only remains the group of Zampra, whose gonophores are cryptomedusoid. A generic
separation between, for instance, the species of Lampra and Corymorpha (Monocaulus) glacialis, will,
as I have recently pointed out (1915), correspond to a generic separation between g# and ? in Z2dw-
laria indivisa Vjinné or Tubularia regalis Boeck. A particular argumentation of the unnaturalness
of this limitation is hardly required. But then it is obvious, as a matter of course, that a generic
separation of the species of Lampra and the other species of Corymorpha cannot be maintained. Also

the species of Zampra must be ranked within the genus Corymorpha.

HYDROIDA 21

Corymorpha nutans M. Sars.

1835 Corymorpha nutans, M. Sars, Beskrivelser og Iagttagelser ...... Da 7 Elo x, Bigg 3

The hydrocaulus, when extended, attains a height of roo mm. It is broad at the basis, attached
to the substratum by numerous rhizoids, and tapering upwards till it reaches its least breadth closely
below the polyp. The basis of the polyp is broad and surrounded by a proximal whorl consisting of
up to 50 tentacles, which, when extended, attain a length of 30 mm. The distal tentacles are small
and placed round the orifice in a main whorl composed of several irregular circles quite closely set.

The gonophores are developed into free medusae with four radial canals, one well-developed

tentacle and three rudimentary ones. The gonophores are developed on 15—20 blastostyles, arising

200 m. SS came mer ere. $000 M. ape etn MR

Text-fig. G. The habitat of Corymorpha nutans in the Northern Atlantic.
(In the hatched regions the litterature denotes a scattered, allthough common occurence),
closely above the proximal whorl of tentacles. The blastostyles bear small alternating branches, each
- 5

provided with a large number of gonophores.

Material:
Iceland, 16 minutes N. W. Akranes, depth 26—30 fathoms (a couple of young polyps).

The occurrence of the species is typically boreal. It is indigenous to the middle parts of the
littoral region. Towards the north it goes along the coast of Norway as far as Lofoten and towards
the south it penetrates to the northern parts of France. The species is recorded by Jaderholm (1909)
from Matotschkin Schar (Nova Zembla) at the depth of between 2 and 5 fathoms. This find is most
peculiar and mysterious. Corymorpha nutans occurs not rarely in the North Sea, and I think Hart-

laub (1907) is right in supposing the specimen from the North Sea recorded by me (1905) as a Cory-

32 HYDROIDA

morpha, to be in fact a young colony of Corymorpha nutans. Remarkably enough, the species has
not yet been met with at the Faroe Islands; but it has been found several times on the west side of
Iceland. At Greenland it is not likely to occur; nor has the species as yet been recorded from this

locality.

Corymorpha glacialis M. Sars.
1859 Corymorpha glacialis, M. Sars, Om Ammeslegten Corymorpha.
1872 A/onocaulus glacialis, Allman, A Monograph of the Gymnoblastic or Tubularian Hydroids,
p- 396.
1876 Amalthea islandica, Allman, Diagnoses of new Genera and Species of Hydroida, p. 256, PI.
IX Fig. 5—6.
21887 Tubularia regals, Bergh, Goplepolyper fra Kara-Havet.
Nec 1893 Amalthea tslandica, Levinsen, Meduser, Ctenophorer og Hydroider fra Gronlands Vestkyst,
os wee
The hydrocaulus, when extended, attains a height of 100 mm. It is wide at the base, where
it is attached to the substratum by numerous rhizoids, and is gradually tapering upwards till closely
below the polyp where its width reaches its minimum. The polyp has a broad base, surrounded by a
whorl of up to 50 tentacles, which, when extended, attain a length of 30mm. The distal tentacles are
small and numerous, placed round the orifice in a main whorl formed by several irregular and closely
set circles.
The gonophores are eumedusoid, with four radial canals, but without rudiments of tentacles.
They are sessile. The gonophores are scattered all over the surface of 30—35 unbranched blastostyles,

the oldest and most developed ones at the apex of the blastostyle.

Material:
Iceland, Offord (without particular data). Original specimen of Amalthaca tslandica.

? The Kara Sea (“Dijmphna”. Particular data are wanting). Labelled Zadelaria regals.

The original specimen in hand of Amalthaca tslandica Allman (1876) proves as clearly as de-
sirable that this species is wholly identical with Corymorpha glacialis. Allman, certainly, states that
the gonophores of the species are provided with four short tentacles, which are also, in his rather
skeletonlike drawings, delineated as rather considerable formations. But in the original specimen can
only in some straggling gonophores be pointed out some accidental wrinkles, which, when acting in
good will, we may consider as the origin of the rudimentary tentacles stated. Other divergencies from
the typical Corymorpha glacialis are, on the whole, not traceable.

A specimen from the Kara Sea has been identified by Bergh (1887) as 7ubularia regalis Boeck.
The specimen is an unquestionable Corymorpha and no Tubularia; indeed, everything suggests that
it is a Corymorpha glacialis, but the state of preservation impedes a safe identification.

According to the particulars in hand Corymorpha glacialis is indigenous mainly to Arctic wa-
ters. It has been recorded from the Varanger fjord (M. Sars 1859), from Nova Zembla (Maren-

zeller 1877), and from Spitzbergen (Broch 1909). But the species also penetrates into warmer water

HYDROIDA 33

layers, as is seen (Text-fig. H) from the finds to the north east of the Faroe Islands and on the south
east coast of Iceland (Broch 1903). As new localities must be added Northern Iceland (Ofjord). On
the other hand, the specimens from Davis Strait, recorded by Levinsen (1893) as Amalthaea tslandica,

prove to belong to Corymorpha groenlandica (Allman).

Corymorpha groenlandica (Allman) Broch.

1876. Monocaulus groenlandica, Allman, Diagnoses of new Genera and Species of Hydroida, p. 257,
Pl. IX, Fig. 7—8.

1893. Amalthea islandica +- Monocaulus groenlandica, Levinsen, Meduser, Ctenophorer og Hydroider

fra Gronlands Vestkyst, p. I51.

200 m. So poo VOGELS case ent ons ens -.1000m. rete ICO

Text-fig. H. Finds of Corymorpha glacialis in the Northern Atlantic.

1899 Lampra atlantica + Lampra purpurea, Bonnevie, Norske Nordhavs-Expedition, p. 20, Tab. II
Fig. 4, Tab. III Fig. r.

1903 -- soca, Swenander, Uber die athecaten Hydroiden des Drontheimsfjordes, p. 6, Taf.
Fig. 1—3.
1909 _ arctica, Jaderholm, Hydroiden, p. 41, Taf. I Fig. g—ro.

1909 Corymorpha spitzbergensis, Broch, Die Hydroiden der arktischen Meere, p. 140.

IgI5 — groenlandica, Broch, Hydroiduntersuchungen IV, p. 11.

The hydrocaulus, when extended, attains a height of 100 mm; it is widest at the base, where
it is attached to the substratum by numerous rhizoids, and is gradually tapering upwards till close
below the polyp where the width reaches its minimum. The polyp has a wide base, surrounded by

The Ingolf-Expedition. V. 6. 5

HYDROIDA

a basal whorl of up to 37 tentacles, which, when extended, attain a length of 4omm. The distal ten-
tacles, when extended, attain a length of 9 mm; they are placed in large numbers round the mouth
in a main whorl formed by two or more irregular and closely set circles.

The gonophores are cryptomedusoid and globular (?) or sub-oval (d), often somewhat tapering
distally, but without any rudiments of tentacles). The gonophores are supported by unbranched and
strongly contractile blastostyles, which, when extended, attain a length of 4o mm. The gonophores
first ripen at the apex of the blastostyle. As many as 32 blastostyles may occur, but, in general, the

number is much smaller; the blastostyles arise close above the basal whorl of tentacles.

Material:
“Ingolf’ St. 102. 66°23’ N., 10°26’ W., depth 750 fathoms, + 0°9 C.
- 107. 65°33’ - 10°28’ - = AQ = + 0°3 -
= 1320; 63°36" “= -7°304 = = YX + 0° -

Greenland: Godthaab (no particulars) [Allman’s original specimen of A/onocaulus groenlandical.
Davis Strait, depth 100 fathoms [labelled Amalthaea islandica\.

Iceland: 66°02’ N., 11°05’ W.
5 miles east of Seydisfjord; depth 435 fathoms.

The fairly well preserved specimens of the material recently collected show the following cha-

racters (all the measurements are given in mm).

= == = = =
Height of! plastostyles | Proximal Tentacles Distal Tentacles
Nr. Finds Hydro- oa! = s | Observations
caulus || Number| Length Number Length Arrangement Length
1 || “Ingolf’ St. 139 go 14 5 ? ? in several close circles 2 Hydrocaulus strongly
extended
le tie we rane .
2 || ‘‘Ingolf’ St. 139 | 60 es I—3 || ? ? in several close circles 2 Blastostyles very strong-
ly contracted
Wet || —_—_—___—. a —_ it a
3 || “Ingolf” St. 107 57 Tease 26 25 | in a double circle formed by 1.5
| alternating displacement
4) “Ingolf? St. 102 | 45 | 10 Bt 23 up to 24 | in several close circles 1.5
=| == | Loe halle | 2 | x f | ==
5 || “Ingolf? St. 102 41 | 8 5 25 24 in a double row formed by 2
| | alternating displacement
| <= EE ne | = — IK ae ee) a
6] Davis Strait | 4o 20 7 24 25 | in several close circles 5
— = — ——— I = = SS —— = _ — ——
7 || “Ingolf? St. 107 | ? 10 |6—13/|| 21 30 | in three irregular rows formed 1.5 | Hydrocaulus more than
| | | by alternating displacement 50 mm high
= ~ — | | |
| = 7 7 7 _ = a a
8 | ‘‘Ingolf” St. 102 ? 9 4 28 up to 23 || in several close circles 2
— | —|}. = = — —— — _— == — — a ——
| s | | :
g || “Ingolf” St. 107 | ? | 16 3—4 24 | 22 in a double row formed by 25a
| I | alternating displacement
10 |66°2°N.11°05' W.| ? | 28 |5—18 22 25-30 ? ? Blastostyles placed alt-
| ernatingly; attempt
at forming two rows
11 || “Ingolf” St. 107 | ? | 14 Ae 18 18 | in three irregular rows formed 2
| | | by alternating displacement

HYDROIDA ac
The species, which is widely distributed in the deeper parts of the cold area, has been found by
several expeditions, and has formed the base of the genus Lampra stated by Bonnevie (1898, 1899).
I have already in works earlier published pointed out that, for several reasons, this genus cannot be
maintained. In the first place, the name of Zampra had already been applied to a subgenus of the
beetle family Buprestidae, and should, therefore, disappear among the hydroids, according to the rules
of nomenclature internationally adopted. Secondly the characters distinguishing Lamfra from Cory-
morpha are not sufficient to justify a separation of genera.
A closer examination of the numerous northern species of Zampra described will show their un-
maintainability. A survey of the figures forming distinguishing characters is obtained by grouping the

criteria stated as follows:

im | 7 eel |
Height of) — plastostyles oe Tentacles |
Nomenclature | Hydro- | Proximal Distal Gonophores
el ~———- = = Ea
caulus | Nember| Length | Number| Length Arrangement | Length |
Monocaulus groenlandica Allman 1876.) 1 inch gate) ? | ca. 20 ‘‘Modera-|| “numerous” | short no tentacles
| | | tely long’)
| |
= ——— —— | ao || i |= =) ae
5 fa | s | | :
Lampra arctica Jaiderholm 1gog .....| 45 mm | 22 |5—Smm | 25 25mm |/5-6closecircles| ? | globular,broadly oval
| | with rounded apex
; 7 - = ‘ ace = a | ¥ ri | Tp || Zz Be . 7 a | .
Corymorpha spitzbergensis Broch 1909..| 60mm | 12 | 5mm | 25 zomm || 4-5 close circles 2 mm) oviform or globular

| | | | without tentacles

Lampra atlantica Bonnevie 1899.... |

| | | set circle |

|
Somm | to |4—6mm] 10 /|10-20 ml several close- a without tentacles
| |
L
|
|
|

Lampra purpurea Bonnevie 1899..... | 100 mm | 10 30-40 mm! 30 30-40 ao two circles | ? without tentacles
} | |
SS = ae ee ae | =e cal i aE EE lapRoTasllios onscreen
Lampra socia Swenander 1903.......) 45mm |1$—32\till25mm)29—37) 35mm | numerous |upto| Qmore rounded,
close-set circles g mm 3 sub-oval,

| |
| | | | | lI | | without tentacles

The original discription given by Allman (1876) is founded on a series of young individuals
from Godthaab, in which it may be observed how the number of proximal tentacles increases by new
tentacles being established and growing out among the old ones. How far the number of tentacles
may increase in this way, cannot be settled. But no definite rule of the increase being trace-
able, we here face one of the reasons of the great varying of the numbers of tentacles. In these young
individuals it is also interesting to observe that the distal tentacles are established quite irregularly
Tab. Il Fig. 14), and that the blastostyles arise as simple fingerformed bulges of the polyp wall. The
gonophores only appear at a rather late stage of development.

The skeletonlike figures and rather deficient diagnosis of the species given by Allman long
impeded its recognition, and, therefore, only a couple of specimens occurring in the museum of Copen-
hagen have later on been correctly referred to his species Alonocaulus groenlandica. Bounevie (1899)
accordingly describes two new, closely related species, Lampra atlantica and Lampra purpurea. ‘The
former species is distinguished from the latter mainly by its small number of tentacles, having only
ten proximal ones. However, even though this difference must be regarded as very large, as far as in
the single specimen of Lampra purpurea as many as thirty proximal tentacles have been observed,
we cannot acknowledge it as a sufficient specifical distinguishing character after the examination of a
larger material of the species. The rather numerous specimens found in the Trondhjem fjord present

5

36 HYDROIDA
so great a range of variability that the number stated in Zampra atlantica must only be considered
as an extreme variation. The variation of the individuals found in the Trondhjem fjord is even larger
than stated by Swenander (1903); individuals have been found with only 15 tentacles in the proximal
whorl. The difference in the shape of the gonophores, being either subglobular or oval with attempts
at tapering, is of little importance. Swenander points out that the female gonophores are more
globose, the male more oval. In a specimen picked up north east of the Seydisfjord (Iceland) the gono-
phores are partly globular, partly oval, with the same attempt at tapering towards the distal end as
is shown in the figure of Bonnevie (1899, Tab. III, Fig. 1a). However, one criterion is still left,
the distal tentacles of Lampra purpurea being arranged in two separate circles, while in other spe-
cies they are placed in several irregular and close-set circles. From the comments of Bonnevie it
appears that the description has mainly been based on the drawings of G.O.Sars, which were exe-
cuted on board ship. In these drawings the double whorl is not peculiarly clearly rendered; nor can,
from the remnants of the original specimen kept, the character be ascertained any longer. From the
table set up of the specimens from the Danish collections, however, it appears that, from individuals
with a distal whorl consisting of two rows to individuals with a distal tentacle whorl of several rows,
every transition may be pointed out. Thus neither this table nor the criteria stated in the other table
may be turned to account for the purpose of attaching any peculiar systematical importance to this
character. ZLampra atlantica and Lampra purpurea, therefore, cannot be recognized as two separate
species, and are moreover identical with Corymorpha groentlandica.

For a thorough examination of the species we are indebted to Swenander (1903), who considered
the Lampra of the Trondhjem fjord as a peculiar species, Lampra soca. From what I have stated
above, the shape of the gonophores, applied by Swenander as a main character distinguishing the
species from Lampra purpurea Bonnevie, cannot be maintained as a criterion. The number of the
blastostyles then remains; Bonnevie, for both the species mentioned, states Io blastostyles; Swen-
ander, for Lampra socia, 18—32. Still Swenander has not found the minimum for the individuals
of the Trondhjem fjord; as a matter of fact, specimens with only 15 blastostyles are now in hand.
In the Danish material collected from the northern Atlantic the number is throughout lower, varying
from 10 to 28, thus bridging the difference between Zampra socia and the species stated by Boune-
vie. Also the other distinguishing characters, the emphatic demarkation of the hydrocaulus from the
polyp, or its gradual transition into the latter, and the colour of the animals, are varying from one
individual to the other, forming no strongly defined limits. The demarkation of the stem from the
polyp more or less emphatic, is, in living individuals, varying according to the state of contraction, as
in other species of Corymorpha. Therefore, also Lampra socia must be considered as a synonym of
Corymorpha groenlandica.

Jaderholm (1909) and Broch (1909) describe two new species, respectively Lampra arctica
and Corymorpha spitzbergensis. The table at once shows that they come within the range of variation
of Corymorpha groenlandica. As to Lampra arctica the short and thick blastostyles, maintained by
Jaderholm (1909) as a good criterion, are in fact to be looked upon as a mere phenomenon of con-
traction which may be partly observed even in preserved material, where in the same individual some

blastostyles may be short and thick, while others are thin and strongly extended. Illustrative in this

HYDROIDA 37

respect is the individual nr. 10 of the first table, the length of the blastostyles varying from 5 to 18
mm., and the thickness being inversely proportional to the length. The rest of the distinguishing
characters fall under what has been earlier stated.

Corymorpha groenlandica is a typical form characteristic of the great deep of the cold area. It
proves to be widely distributed, from Spitzbergen to the Faroe Islands, and from Norway to Green-
land. It has also been recorded from Davis Strait. In the seas far to the north it rises to more shallow
waters. Thus it has been recorded near Spitzbergen at the depth of only 45 metres (Broch 19009).

A remarkable geographical exception is formed by the occurrence of the species in the deeper Atlantic

MOO Tas Se OS een -.f000m. bere Oe

Text-fig. I. Localities of Corymorpha groenlandica in the Northern Atlantic.

strata of the Trondhjem fjord. At present the occurrence of the species in this locality cannot be
accounted for. But a great deal may be said in favour of the notion that we have here in hand a
relict form, which has been able to accommodate itself to the altered circumstances in the same way
as Tubularia regalis Boeck and Stegopoma plicatile (M. Sars) which are rather frequently occurring

on or at the Lophohelia reefs of the fjord.

Corymorpha sp. indet.
Indeterminable remnants of species of Corymorpha occur from the following localities:
“Ingolf’ St. 28, 65°14’ N., 55°42’ W., depth 420 fath., + 3°5 C. attached to the tube of a Pectinaria.
_ Si24y07-40 = 15401 =) — 495, ——. » = 0:0 -

HYDROIDA

| Oo
ee)

Section Filifera Kiihn.

Family Clavidae.

Hydroids forming colonies, with polyps fusiform or capitate, the distal part of which is coni-
cally tapering. The stinging cells are small and rodformed. The tentacles are filiform, irregularly dis-
tributed over the body of the polyp, now and then showing a heterogeneous development or even
reduced to a single large tentacle. The endoderm forms a homogeneous gastral cell-layer through

the whole of the polyp. The colonies have no calcareous skeleton.

The family C/lazvidae, as it is here defined, includes the genus much in dispute A/onobrachium,
which has been distinguished by most investigators as the representative of a family of its own, dZo-
nobrachitdae. ‘This family is maintained even by Kiithn (1913), who has obviously failed to notice
the significant pointing out by Vanhoffen (1909) of the heterogeneous development of the tentacles
of Campaniclava clionis Vanh 6ffen, forming an obvious link between AMlonobrachium and the other Cla-
vidae. Vanhoffen, therefore, does away with the family Monobrachudae and refers Alonobrachium

to Clavidae. In this he is rightly followed by Stechow (1913).

Gen. Clava Gmelin.

The reptant colonies have polyps capitate or subfusiform with filiform tentacles irregularly
distributed over the polyp. The proboscis is conically pointed. The hydrocauli are not surrounded
by any distinct stiff perisarc. The gonophores are clustered on the polyp below the portion bearing

tentacles, or seated on the reptant stolons either solitary or in clusters.

According to this diagnosis also the genus Rhzzogeton must be included under Clava. The two
genera have hitherto generally been distinguished on the ground that in AAzzogeton the gonophores
are seated on the stolons, while in Clava they are borne by the polyp itself. This criterion, however,
is too insignificant to justify a division of genera, and it is also suggested by Stechow (1913) that
very likely the two genera have to be united. In his key of genera, indeed, Stechow puts down

Rhizogeton in a parenthesis under Clava.

Clava multicornis (Forskal) Gmelin.
1775 Hydra multicornis, Forskal, Descriptiones animalium, p. 131.
1776 — sguamata, Miller, Zoologia Danice Prodromus, p. 230.
1788 Clava parasitica, Gmelin, in Linné: Systema natura Ed. 13, vol. I, p. 3131.
On the reptant stolons the capitate or almost fusiform polyps are placed in close or opener
clusters. The stem of the polyp is without perisarc. The filiform tentacles are irregularly distributed
over the distal parts of the polyp.

The gonophores are cryptomedusoid, and placed in larger or smaller groups like clusters of

grapes closely below the portion of the polyp bearing the tentacles.

HYDROIDA 39

The species may be divided into two forms:

Forma genuina, growing, in colonies more openly constructed, on stones and shells (Mytilus);
it is delicately built and bluish or rose-coloured.

Forma sguamata forming clusters of polyps more brick-coloured or yellowish-red on the leaves

of Fucoideae; its polyps are large and robustly built.

Material:
Iceland: Reykjavik depth 3—4 fathoms.
Vestmanney on the shore (on /wcordeae)
The Faroe Islands: Sundelaget
north of Kvalvik on the shore (on Fucordeae)

(There also occur specimens marked “Faeré” without particular data).

Clava multicornis and Clava squamata are recorded by most investigators of hydroids as two
separate species; the distinguishing characters, however, are rather vague, being made out by the
closer or opener occurrence of the polyps in the colony or by the colour of the colonies. A copious
material from various localities, in fact, presents all transitions possible, and it is virtually impossible
to draw any certain limit between the species. A closer inquiry soon makes clear to us that the
points of difference must be of biological nature, and the two species, therefore, have to be regarded
only as biologically determined “forms” of a single species, which I, accordingly, denominate forma

genuina and forma sgumata. The occurrence of typical colonies of the forma .exwina, which are, in

200 m.

oe eee aneoan came. 2000 M.
Text-fig. K. The distribution of Clava multicornis in the Northern Atlantic

(In the hatched part of the Norwegian coastal region the occurrence is rather scarce)

40 HYDROIDA

fact, rather rare and scattered, is bound to substrata of stones, which may be, at a pinch, replaced by
the shell of a AZytilus, while the colonies luxuriantly developed of the forma sgwamata are resident on
the leaves of the /wco¢deae, where certainly the supply of food is much more copious.

The description of Forskal (1775) being older than that of O. F. Mtiller (1876), we have
according to the rules of nomenclature in force, to drop the specific name employed by the latter,
Clava sguamata and to maintain the denomination bestowed on the species by Forskal, Clava multt-
cornis. Its limitation from the American species Clava leptostyla 1, Agassiz, has not as yet been
ascertained, and it seems on the whole questionable if the two species are really to be distinguished.

Clava multicornts is a boreal species, which seems, nevertheless, to be able to penetrate far
into the Mediterranean (Babi¢ 1go4). It is a littoral form, and forma sgzwamata has been found only
in the tidal zone; forma geruzina, on the other hand, at rare intervals, has been met with a little ben-
eath the tidal zone in places with rather small salinity. Fabricius (1780) records the occurrence
of the species at Greenland without particular statement of locality; however, it has not afterwards
been observed in this place. On the other hand, the species seems to occur not unfrequently on the
south west coast of Iceland. It is frequently met with at the Faroe Islands, and is found everywhere
round the British Isles and on all coasts round the North Sea. Its occurrence at the northern parts

of the coast of Norway is not sufficiently accounted for, but does not seem to be particularly frequent.

Gen. Merona Normann.

From the reptant stolons arise unbranched, chitinous polyp stems. In the upper part of the
stem the perisarec is so wide that the polyp can be retracted into it, though developement of a hydro-
theca is not indicated. The filiform tentacles are irregularly spread over the polyp. The gonophores

are borne upon reduced polyps (blastostyles) arising from the reptant stolons.

With great hesitation I set up AZervona as a genus of its own. It is distinguished from Cory-
dendrium van Beneden (1844) only in mere trifles of no great importance. Thus its polyp stems
are unbranched, while the hydrocaulus of Corydendriwm is richly branched. Another distinguishing
character may perhaps be sought in the quality presented by d/erona in its wide perisarc, into which
the polyps are retractile. But none of these criteria can be said to be of properly generic value. When,
nevertheless, J/evona is provisionally maintained, it is due to the fact that only an exceedingly scarce
material of a single species is in hand, and that the state of preservation of this material allows of

no closer inquiry into the polyps.

Merona cornucopiae Norman.
1864 Tubiclava cornucopiae, Norman, On undescribed British Hydrozoa, Actinozoa and Polyzoa, p. 357.
1865 Merona _ Norman, On Merona, an undescribed genus of British Hydrozoa, p. 262.

The hydrocauli are unbranched and attain a height of about 5 mm.; the stems are narrowest

at the base and increase gradually in diameter till they attain their greatest width closely below the

HYDROIDA 4i
extended polyp; they are without rings; at most there is some faint and irregular wrinkling here
and there. The polyp is fusiform with the tentacles irregularly distributed all over the surface; the
polyp may be retracted into the broader distal portion of the hydrocaulus.

The structure of the gonophores seems to be strongly reduced. They are developed at the

upper part of blastostyles without tentacles, at most 1 mm. high.

Material:
The Faroe Islands: 13 miles West to South of Munken, depth 150 fath. (on Cards sp.).

- = _ 9 — East South East of Bispen, — 70 — (- — =)

200 m. fea yaw fares fee (OO OF, SS CIC ICR Te RR ee 2000m.

Text-fig. L. Localities of Merona cornucopiac @ and Monobrachium parasitum @ in the Northern Atlantic.

Merona cornucopiae was first described as a Tubiclava by Norman (1864). But as the latter
genus is characterized by the gonophores being borne on the polyps, he thought he had better set
up a new genus A/erona (1865) for the species in hand, bearing its gonophores on polyps strongly
reduced or on blastostyles. This criterion, however, is of subordinate importance and would by no
means justify the separation of two genera. However, from the drawings occurring in literature, a
much essential point of difference urges itself. The perisarc of the species of Zedérclava is not so wide
that the polyp can be retracted into it, while this is the case with Merona. The division, therefore,
seems well founded. But at any rate a renewed examination of the two genera is needed.

Merona cornucopiae seems only to occur attached to shells of living mollusks, and has been
found on species of the genera Cardium, Astarte, and Dentalium. The species does not seem to be
very frequent; it has previously been recorded from the sea to the north of the Shetlands at the

depth of 80-100 fathoms, and from the coast of Northumberland. To these localities are now to be

The Ingolf-Expedition. V. 6. 6

42 HYDROIDA

added the-seas to the south of the Faroe Islands at the depth of 70—150 fathoms. All the finds are

thus situated in the boreal area, on the border of the warmer Atlantic regions (Text-fig. L).

Gen. Monobrachium Mereschkowsky.

Reptant colonies, whose cylindric polyps are provided with a solitary large tentacle. Besides
the nourishing individuals bearing tentacles, also machozooids with no mouth and no tentacles occur.
The polyps have no distinct stem and are not covered with perisarc. The gonophores are eumedusoid

and attached to the stolons.

The very peculiar Arctic genus of hydroids first described by Mereschkowsky (1877) has been
more closely investigated by Wagner (1890) and Bonnevie (1899). In the only species known of this
genus the eumedusoid gonophores have a rudimentary spadix, and the germ cells are accordingly
developed along the radials canals. On this ground Bounevie maintains that the species is closely
related to the Lepfomedusac, and that the genus has to be placed proximately between athecate and
thecaphore hydroids. Kiihn (1913), on the other hand, holds that the organisation of the gonophore
cannot be considered as any certain proof justifying such a supposition, and points out that the trans-
ition of the gonophore from independent free existence into sessile mode of life can effect a secondary
displacement of the gonads in many different ways without any necessity that this should be indica-
tive of nearer or remoter relationship. Apart from this, however, there is an additional reason against
the supposition of Bonnevie. As is pointed out by Vanhdffen (1909), we have in hand a medusa-
form obviously nearly related, Cafablema, which, when somewhat damaged, is very easily mistaken
for a Leptomedusa, but which is, in fact, a genuine Zvavide. Vanhoffen even presumes that Ca/fa-
blema really is the medusoid generation of Monobrachium. But in that case it remains to show that
the gonophores of Monobrachium are not sessile as they have hitherto generally been supposed to be.

The explanations of Vanh6ffen (1909) and Ktihn (1913) make good that A/onobrachium takes
no intermediate place between athecate and thecaphore hydroids. But the place of the genus among
the athecate hydroids would still be equally uncertain if the peculiar species Campaniclava clionts
Vanh offen (1909) had not shown us, by its heterogeneous development of the tentacles, the unquesti-
onable link between A/onobrachium and the normal-looking forms of Clava. Therefore there is no
reason any longer to regard the genus as the representative of a peculiar family; as pointed out by

Vanhoffen, it ought to be classed with the Clavidae.

Monobrachium parasitum Mereschkowsky.
1877 Monobrachium parasitum, Mereschkowsky, On a new Genus of Hydroids, p. 225, pl. 5 fig. 1—6
pl. 6 fig. 7—14.
1899 — parasiticum Bonnevie, Norske Nordhavs Expedition, p. 51.
Reptant colonies, whose polyps are dimorphically developed; beside cylindric polyps with ori-

fice and a vigorous tentacle, also machozooids without mouth or tentacles occur, The nourishing

HYDROIDA 43

polyps are provided with a ring of stinging cells above the base of the tentacle. The stolons form a
network of anastomosing tubes.
The gonophores are eumedusoid with a rudimentary spadix and with the generative cells

placed along the four radial canals. The colonies are bisexual.

Material:

Greenland: Egedesminde (on Zedlina calcarea).

The Kara Sea (“Dijmphna”).

Monobrachium parasitum is indigenous to the middle parts of the litoral region far to the north.
It is recorded from Spitzbergen, the Kara Sea, the White Sea, and the west coast of Greenland

(Text-fig. L).

‘amily Bougainvilliidae.

Hydroids forming colonies with polyps fusiform or capitate, whose oral portion is conically
pointed. The stinging cells are small and rodshaped. The tentacles, which are filiform, are placed in
a main whorl round the polyp; the stinging cells are equally distributed all over the surface of the
polyps or in less distinct transverse belts round them. The polyps are quite naked or surrounded by
a jellied, lithe, and pliable pseudohydrotheca below the tentacle whorl. The endoderm is differentiated
into an oral portion, consisting of indifferent small-nucleated cells between which occur a large number
of mucous gland cells, and the proper gastral portion; the limit is formed by the tentacle whorl. The

colonies have no calcareous skeleton.

The diagnosis states for the family the same range as was practically already given by Bon-
nevie (1899), whom the later authors have generally followed. Kitilhn (1913) divides the family into
three subfamilies, two of which, //ydractinitnae and Atractylinae, are represented in our northern seas,
The main distinguishing mark stated by Kithn is that //ydractiniinae are stated to have a vigorous,
crustformed skeleton, while Afractylinac, on the other hand, have hydrocauli covered with periderm.
However, this character does not seem to be of the importance Kiihn attached to it. In young
colonies the stolons have not coalesced into a crust, and the development of the skeleton is not parti-
cularly vigorous. There is even every probability that several species of S¢y/act’s do not at all assume
such crustformed skeleton-formations, even when advanced in life. On the other hand, we also know
species of Aydractiniinae, in which the hydrocaulus covered with periderm has been reduced to a mere
minimum. The character, therefore, must be characterized as a merely gradual one, and can hardly be
turned to account as fundamentum divisionis for higher groups.

A very different interest is attached to the peculiar occurrence of pseudohydrothecae met with
in the Bougainvillidae. 1 set aside the socalled pseudohydrothecae of Clathrozoon (the subfamily /7y-
droceratininae, stated by Kiithn 1913); in fact, this group is not yet so well known that we are able
to judge of it entirely, and its “pseudohydrothecae” do not seem to form such a parallel with the for-
mations of the thecaphores as those found in certain other Bougainvillitdac, namely in Perigo-
nimus. In this species the ectoderm of the polyp has secerned a jellied pseudohydrotheca, which has

coalesced with the polyp along its distal margin, and to which the basal portion of the supporting
6*

44 HYDROIDA

lamella of the polyp is attached by small chitinous bodies similar to those found in several thecaphores.
This pseudohydrotheca is but little visible, or, with intact polyps, when they are extended, almost
untraceable, while in contracted polyps it lies round the basal portion of the polyp like a cup richly
folded. It might be obvious to regard it as the precursor of the real hydrotheca. Perhaps it might
be regarded as a character sufficiently important for the purpose of distinguishing a subfamily: How-
ever, the matter has, as yet, been too little examined as to allow the forming of a reasonable opinion;

we have, provisionally, to regard it as a generic character.

Gen. Hydractinia van Beneden.

The stolons of the reptant colonies, when young, will generally form an open meshwork which
afterwards most frequently changes into a continuous chitinous crust. The crust is commonly carrying
spines of various appearance, or may grow out into branched formations of colonies. The polyps are
cylindrical or capitate with conically pointed oral portion. The tentacles are placed in a whorl below
the mouth. There is no erect hydrocaulus covered with perisarc. The polyps are heterogeneously devel-
oped into larger nourishing individuals bearing tentacles and into spiralzooids bearing no tentacles; the
latter occur at the extremities of the colonies. — The gonophores are supported by polyps more or

less transformed (blastostyles) or arise directly from the stolons.

According to this diagnosis, also Podocoryne, Oorhiza and Stylactis, earlier set up as genera
are included under //ydractinia. The only reason of distinguishing between //ydractinia and Podo-
coryne has been sought in the power of the last-mentioned genus of producing free-swimming medusae.
However, Bonnevie (1899) has described a couple of species, Hydractinia Allmani and Hydractinia
ornata, having medusoid gonophores less strongly reduced with radial canals, and from Africa has
been recorded a species, ydractinia Michaelsent Broch (1914), whose male gonophores are perfect
medusae, which, however, do not seem to break away normally. Also Kiihn (1913) seems to incline
to the opinion that the separation of the two genera is questionable. The intermediate forms of gono-
phores mentioned, in fact, forbid the drawing of a certain limit between the genera, and, therefore, the
proper thing to be done, is, indeed, to draw in Podocoryne under Hydractinia.

The genus Oorhiza is based on the fact that the gonophores are seated, not, as in //ydrac-
tinia, on blastostyles, but, on the contrary, on a short stem rising directly from the stolons. A review
of our northern species of //ydractinia, however, shows that, in fact, this criterion is of no vital im-
portance. In /ydractinia humilis Bonnevie and /ydractinia Sars Steenstrup the gonophores
are borne on polyps fully developed of the same size as the sterile nourishing individuals; in //y-
dractinia carnea M. Sars the polyps bearing gonophores are, certainly, fully developed individuals,
provided with tentacles; but they have a smaller number of tentacles, and are smaller than the sterile
nourishing polyps. In //ydractinta Alimani Bonnevie, Hydractinia ornata Bonnevie, and /fydrac-
tinta echinata (Fleming) the reduction is carried still further, the tentacles being reduced or wholly
disappearing, so that the bearers of the gonophores are here typical blastostyles. In //ydractinia carica

Bergh, finally, the polyp has been reduced to a stem, round the apex of which the gonophores are

HYDROIDA 45

placed in a whorl. In fact, between this condition of things and a solitary gonophore seated termin-
ally on a polyp wholly reduced to a stalk, there is no great gap, and at any rate the criterion is not
essential enough to be turned to account as fundamentum divisionis. Also Oorhiza has, accordingly,
to be inciuded as a synonym under //ydractinia.

Stylactis is yet left to be mentioned, being distinguished by the stolons forming an open mesh-
work and no continuous chitinous crust. In his excellent elucidation of //ydractinia and Podocoryne,
Hincks (1868) calls attention to the fact that, in the species then known, the stolons at first form
an open mesh-work and do not till later on coalesce into a continuous crust. Young colonies of //ydractinia
carnea, Which are in our Norwegian seas very commoniy observed on living specimens of Massa reticu-
fata, in most cases show this open mesh-work of stolons and, therefore, easily run the risk of being
undiscerningly characterized as Stylactes. In the African species, Mydractinia Michaelsent Broch
and /fydractinia fallax Broch, large colonies show a mixture of characters of S¢ylactis and of //y-
dractinia, and, accordingly, there is no reason to maintain the two groups as distinct genera. They
communicate with each other by intermediate forms. It is probable that several species of Stylactis
have been based on young colonies of typical species of //ydractinia. This probability, indeed, cannot
be contested even by the occurrence of gonophores, because, in young colonies of [Yydractinia carnea,
where the stolons have not yet coalesced into a crust, gonophores are frequently observed. A species
as Stylactis arctica Jaderholm (1902) has obviously to be judged summarily as such a young //j-

dractinia. Also Stylactis, therefore, has to be included among the synonyms of //ydractinza.

Hydractinia Sarsii (Steenstrup) Bonnevie.

1846 LPodocoryna carnea, M. Sars, Fauna littoralis Norvegiz, Heft 1, p. 7.

1850 Podocoryne Sarstz, Steenstrup, in: Liitken, Nogle Bemzrkninger om Medusernes systematiske
Inddeling, p. 33.

1872 Stylactis — Allman, Monograph of the Gymnoblastic or Tubularian Hydroids, p. 303.

1892 Podocoryne carnea, Levinsen, Meduser, Ctenophorer og Hydroider fra Grénlands Vestkyst, p. 11.

1899 - — pars, Semundsson, Bidrag til Kundskaben om de islandske Hydroider, p. 50.

1899 f/ydractinia sarst, Bonnevie, Norske Nordhavs Expedition, p. 45.

The reptant stolons are covered by a continuous chitinous coenosare, whose surface is studded
with small spines, among which are found, often by groups, large, vigorous thorns, up to 0.5 mm. high,
of irregular conical shape with closed apex abruptly cut off. The polyps attain a length of 2.5 mm.
and have 10 or 20 tentacles in a dense, proximately double, whorl, below the oral portion. Spiral-
zooids have not yet been pointed out.

The gonophores are cryptomedusoid and placed, to the number of three or six, round fully

developed polyps of the same size as the sterile nourishing individuals.

Material:
Greenland, the harbour of Godthaab ... depth 12 fath. (on Ayas araneus),

Iceland, Seydisfjord (on Carcinus maenas).

46 HYDROIDA

The well developed colony in hand has been wrongly determined as Podocoryne carnea. It is
hardly intelligible that Bedot, in his “Matériaux pour servir 4 histoire des Hydroides”, should have
followed Allman (1872) and referred this species to Stylactis,; it is one of the few species of /7/y-
dractinia which, even at the extremities of small colonies, show no indication of the open network of
stolons for which S¢yacézs should be distinguished.

ihe species seems to be a boreal one, but it has hitherto been recorded only from very few
localities, as it has probably been mistaken for Hydractinia carnea also by investigators subsequent to
M. Sars (1846). It has previously been recorded only from the coast of Norway near Bergen. In the
Danish collections is found a well developed, though sterile, colony from Iceland (Seydisfjord),

seated on the claw of a strand-crab. It seems to be the same species which is recorded, by the name

. 200 m, amin win OOO 2 pen tooom. see, 2000 mM.
Text-fig. M. Finds of Hydractinia Sarsi @ end Hydractinia carica @ in the Northern Atlantic.

of Podocoryne carnea, from the north of Iceland, on the operculum of a Galanus Hammer? (Se munds-
son 1902, 1911); here is only found the chitinous crust; but it differs considerably from the crust found
in Aydractinia carnea, aud, on the contrary, wholly agrees with //ydractinia Sarsit (Tab. I Fig. 12).
Finally also West Greenland (Godthaab) has to be added to the localities where the species has

been found (Text-fig. M).

Hydractinia echinata (Fleming) van Beneden.
1828 Alcyontum echinatum, Fleming, A History of British Animals, p. 517.
1841 //ydractinie, van Beneden, Recherches sur la structure de lPoeuf dans un nouveau... genre de
Polype (genre Hydractinie), p. 89.

1909 HHydractinia monocarpa pars, Broch, Die Hydroiden der arktischen Meere, p. 199.

HYDROIDA 47

The reptant stolons are covered by a continuous chitinous coenosare, whose surface is studded
with small prickles, among which occur larger chitinous spines about 1.5 mun. high, provided with lon-
gitudinal rows of more or less regular small teeth. The large spines now and then show a tendency
to divide at the apex. The polyps are up to 4 mm. long, whitish or faintly reddish, with 20—30
tentacles in a dense whorl below the oral portion. The tentacles form a belt which appears double
because of alternating displacement. Spiralzooids without tentacles occur along the margin of
the colony.

The gonophores are cryptomedusoid, placed, to a number of 3 or 6, round reduced polyps with

rudimentary tentacles.

Material:
Greenland: Upernivik, depth 80—g0 fathoms without particular data, from a cod’s stomach.

Skagerrak: the channel near Vinga (Bohuslan), depth so fath.

Hydractinia echinata in its large chitinous skeleton-spines (Tab. I Fig. 9 and 10) has a very
typical armour impeding a confusion with other northern species. It is an Atlantic-boreal species,
showing a great power of enduring both high and low temperatures. It occurs very frequently in
the North Sea, along the coasts of Great Britain and Ireland, goes to the south as far as into the
Mediterranean, and is also found on the east coast of North America. The species belongs to the
litoral region and almost always goes together with Luwpagurus Bernhardus, on whose house it settles.
When we consider the distribution of the species along both sides of the northern Atlantic, we must wonder

that it has not yet been observed at the Faroe Islands, and that only a single specimen has been met

sdeececeserereseres 200 M, jo ow ds we O00 IT,

ee eo ee tooom, En HL ALLE
Text-fig. N. The occurrence of Aydractinia echinata in the Northern Atlantic.
(The hatched parties denote according to litterature a scattered allthough common occurence).

48 HYDROIDA

with at Iceland. This specimen which was found on the north side of the island, was originally
recorded by Winther (1880), and has afterwards been revised by Semundsson (1902). It is a pecu-
liarity of the specimen that it is seated on the operculum of a Balanus Hammeri, and not on the
house of the Bernhardus crab. The species has been recorded once in the Arctic water-layers near Jan
Mayen (v. Lorenz 1886). In a previous work (1909) I gave utterance to the supposition that the
variety recorded by Levinsen (1892) had probably to be referred to the high-arctic species Wydrac-
tinta monocarpa Allman. An examination of the specimens mentioned, however, shows that this suppo-
sition is wrong. ‘The specimens are unquestionable //ydractinia echinata with skeleton strongly deve-
loped. One of the specimens is distinguished by being attached to the shell of a living Buccinum

hydrophanum. The species, thus, proves able to occur now and then under wholly high-arctic conditions.

Hydractinia carica Bergh.

1887 /ydractinta carica, Bergh, Goplepolyper fra Karahavet, p. 3, Taf. 28, Fig. 1.
I

1899 — minuta, Bonnevie, Norske Nordhavs-Expedition, p. 48, Tab. I, Fig. 3.

The reptant stolons are covered by a chitinous layer of coenosarc, without small pricles, but
bearing here and there vigorous spines, singly placed and up to 05 mm. high, conical with rounded
apex. The polyps attain a length of 2 mm, and have 10—14 rather vigorous tentacles placed in a
single whorl below the oral portion. Spiralzooids are not traceable.

The gonophores are cryptomedusoid, placed, to a number of 3—6, round polyps almost wholly

atrophied, forming, if anything, only a short stalk, or showing rudiments of tentacles slightly indicated.

Material:

The Kara Sea: Petuchoffskoi Schar depth 7 fath. (the original specimen described by Ber gh 1887).

An examination of the original specimen, determined by Bergh, shows with full certainty
that it is the same species that has afterwards been described by Bonnevie (1899) by the name of
Flydractinia minuta, The diagnoses, however, when compared, will show some points of difference.
Bonnevie does not mention the skeleton-formations at all while on the other hand, the statements
of Bergh convey the impression of a greater resemblance to Hydractinia echinata than it really bears.
Flydractinia carica lacks the small prickles found in the species last mentioned, and more vigorous spines
also occur rather scarcely; the latter (Tab. I, Fig. 11) are smooth and more conically tapering than those
of Hydractinia Sarst. The main difference, however, between the diagnosis of Bonnevie and that
of Bergh is implied in the mention of the blastostyles. Bergh states in his diagnosis “Sporosacs
borne on very short, rudimentary hydrants, without or with very few (1—4) tentacles”, while in the
diagnosis of Bonnevie we find “Fixed gonophores without radial canals, from 3 to 5 in circle round
the inconspicuous blastostyles”, and in her short comment Bonnevie further states that the species
is distinguished for “the complete atrophy of the gonophore-bearing hydranths”. The specimens deter-
mined by Bergh show a great varying as to the development of the fertile polyp; it may, as he tells
us, have 1—4 tentacles; but they are a great deal more reduced than is apparent from his pictures,

and agree better with the drawings published by Jderholm (1909, Pl. 2, Fig. 1o—11). However,

HYDROIDA 49

there are in the colonies also numerous blastostyles, which are wholly devoid of rudiments of tentacles,
and accordingly only forming a stalk in the same way as is indicated by the diagnosis of Bonnevie.
But there always occurs a small polyp, and a “complete atrophy” of the polyp is in no case demon-
strable; nor is it obvious from the imperfect figure of Bonnevie (1899, Tab. I, Fig. 3). — The great
variation of the blastostyles of the original specimens determined by Bergh, shows us that the
species stated by Bonnevie may be founded on a colony where the blastostyles carrying tentacles
were reduced to a minimum in number. But this does not give sufficient reason for maintaining it
as a peculiar species beside //ydractinia carica.

Hydractinia carica is an Arctic litoral species, which, in boreal waters, proves able to penetrate
along the West coast of Norway as far as Bergen (Text-fig. M). It has been found elsewhere only
in high arctic regions, in the Kara Sea, in the Murman Sea, and at Spitzbergen. It has also been re-

corded by Jiderholm (1909) from Davis Strait.

Gen. Bougainvillia Lesson.

Upright colonies with branched hydrocauli clothed with a perisarc. The polyps are fusi-
form with the tentacles placed in a Whorl below the conically pointed oral portion. The polyps are
naked without the slightest attempt at formation of pseudohydrotheca round their proximal portion.
The gonophores are placed on the stems of polyps fully developed or reduced (blastostyles). In the
latter case, the unbranched polyp stem will sometimes rise from the hydrorhiza instead of from the

hydrocaulus,

A closer inquiry into the distinguishing characters and their systematic value, shows us that there
is no reason to distribute the species of Bowgainvilla on the three genera Bougainvillia, Dicoryne,and Hetero-
cordyle. Sufficient cause for distinguishing between Bougainvillia and the two other genera is not at all
given by the fact that the former has medusoid gonophores, while the two other genera have styloid go-
nophores. In mentioning the genera earlier treated, I have sufficiently explained the insignificance of this
criterion as to classification. Then remains the other distinguishing mark that the gonophores of Lowgarn-
villza develop on the stems of some fullgrown polyps, while in Dicoryne and /feterocordyle they are devel-
oped on the stems of reduced polyps (blastostyles). The genus //ydractinia shows us a full parallel to this
condition of things. But because of the many and close connecting links between one extreme and
the other, it has been agreed that the stronger and weaker specializing into nourishing polyps and
blastostyles cannot be employed as a generic character. When, on the other hand, this has been done
with Bougainvillia and Dicoryne and Ffeterocordyle, the only reason must be that, between the few
species known of these genera, most of the links occurring in //ydractinia are wanting. This lack,
in fact, is not a sufficient reason to elevate, in one case, the character to an importance which is denied
in another case, even within the same family. It is not right to base the genera Bougainillia, Di-
coryne and //eterocordyle on characters that must be used with discretion as specific characters
in Hydractinia, Further, as to the distinguishing mark between Decoryne and Heterocordyle, it is
still more diminutive. /e¢erocordyle conybeari Allman, the only species known of the genus, is so like

The Ingolf-Expedition. V. 6. 7

50 HYDROIDA

Dicoryne conferta (Alder) as to confusion, and the two species have probably more than once been mis-
taken for one another. Both the species have styloid gonophores; but in Heferocordyle they are ses-
sile, while in Décoryne, when ripening, they assume cilia all over, develop two tentacles, and break
away. This is, unquestionably, a phenomenon of mere biological adaptation and cannot be recognized
as sufficient for distinction of genera as long as it is not accompanied by a thorough change of the
organization of the sterile parts of the colony. It is evident that Dyucoryne and //eterocordyle must be

drawn together into one genus, and moreover that this genus must be united with Bouganeillia.

OO TR OOS 600m. canes entase -.1000m., et

Text-fig. O. The habitat of Bougainvillia conferta in the Northern Atlantic.
(In the hatched regions the litterature denotes the occurence of the species without strict localities).

Bougainvillia conferta (Alder).
1856 Eudendrium confertum, Alder, A Notice of Some New Genera and Species of British Hydroid

Zoophytes, p. 354, pl. 12, fig. 5—8.

The colonies attain a height of up to 15 mm., and exhibit a rigid appearance. They have a
distinct main stem with short side-branches. The perisare is vigorously developed and dark brown-
coloured. The small fusiform polyp attains a length of about 0.5 mm.; it wears about 16 tentacles in
a single whorl below the oral conically pointed portion.

The gonophores are styloid and break away. When ripening, they assume a peculiar oviform
shape, develop two filiform tentacles, and put on a complete suit of cilia all over. The gonophores
are seated, gathered in a belt, somewhat below the apex of blastostyles, which arise from the hydro-

caulus or, in smaller numbers, from the hydrorhiza. The blastostyles show no indication of tentacles.

HYDROIDA

nN
ms

Material:
Iceland: Talknafjord (without particular data).
Reydarfjord, depth 163 metres.

The Faroe Islands (without particular data).

Bougainvillia conferta is a southern-boreal species penetrating as far as into the Mediterranean;
towards the north it goes, along the coast of Norway, only as far as Lofoten. It has been recorded several
times from Iceland, in the warmer water-layers along the west- and south-coasts of the island, but it
has not yet been pointed out at Greenland. As a new locality must be added the Faroe Islands. The

species is indigenous to the litoral region.

Gen. Perigonimus M. Sars.

The hydranth stems rise immediately from the reptant stolons, or there are formed upright
rhizocaulomes bearing the polyps. The polyp stems are sometimes divided into a couple of branches;
still hydrocaulus, properly speaking, cannot be recorded. The polyps are fusiform, with the tentacles
placed in a whorl below the conically pointed oral portion; below the tentacle whorl they are sur-
rounded by delicate pseudohydrothecae, superiorly connected with the ectoderm of the hydranth, and
inferiorly passing into the chitinous perisarc of the stem. The stinging cells show attempts at being
arranged in transverse belts on the tentacles. The gonophores are placed singly on the stolons or on

the hydranth stems, most frequently attached to the latter by a short stalk.

The distinguishing marks between Pertgonimus and Bougainvillia, indeed, seem to be so in-
significant that the conclusion might be obvious that both genera should be united into one. The
Perigonimus polyp, when wholly extended, is very easily mistaken for a Bowgainvillia. However, there
is an essential difference between the two genera which necessitates a separation. Their medusae
even belong to different families, the Bougarnvillia-medusae being typical Alargelidac, while Perigont-
mus gives rise to Traridae (see Hartlaub 1913). As far as the nurse polyp is concerned, we must
notice the difference existing between the wholly naked Bougaimaillia-polyp and the hydranth covered
with pseudohydrotheca of the Perzgonimus-polyp. The pseudohydrotheca has been pointed out by sev-
eral authors and has been emphasized as generic character particularly by Broch (1911). A closer
inquiry into this formation has been made by Hadjii (1913, 1914), who has studied it most thoroughly
in the Adriatic species, Perigonimus Cortd Hadii and Perigonimus Georginae Hadii; the latter spe-
cies is very nearly related to Perigonimus repens (Wright). Hadii points out that Perzgonimus is
provided with a sort of hydrotheca, the essential substance of which is jellied and accordingly not
entirely parallel with the hydrotheca of the thecaphore hydroids. For this jellied polyp case, which
is, in its outer margin, connected with the ectoderm of the polyp, I, therefore, employ the denomina-
tion of “pseudohydrotheca”, earlier employed for the chitinous false hydrothecae of Clathrozoon. In the
case of Chlathrozoon, however, the formation seems to be quite different, and the denomination, on

that account, rather misleading; indeed, we had better employ the term of “false hydrothecae”. Hadi

7

52 HYDROIDA

calls our attention to the interesting fact that the polyps are basally attached to the pseudohydrotheca
by a whorl of small chitinous bodies similar to that met with in Haleciidae, Plumularudac, Lafoéidae,
and Campanulariidae ; they actually attach the supporting lamella to the polyp case. Systematically,
however, hardly any particular importance can be attached to this character. The chitinous bodies
occur on the passage from the pseudohydrotheca to the hard periderm of the stem. Also the periderm
of the stem has, in most species of Perigonimus a jellied cover, to which a lot of foreign bodies fasten
themselves so as to give the colony a foul appearance.

The stinging cells in the tentacles of the Pervzgonimus-species show attempts at an arrange-
ment by belts. But it is not here so pronounced as in the Lwdendridae and the thecaphore hydroids.
This criterion, together with the pseudohydrotheca, suggests that Perigonimus must be more nearly

related to the thecaphore hydroids than most other athecate hydroids.

Perigonimus repens (Wright) Allman.

1857 Eudendrium repens, Wright, Observations on British Zoophytes, p. 84, pl. 82, fig. 8—9.
1864 Perigonimus — , Allman, On the Construction and Limitation of Genera among the Hy-
droida, p. 365.

nec IQII — — , Broch, Fauna droebachiensis, p. 14.

From the reptant stolons proceed thin polyp stems, up to 5 mm. long, more rarely dichotomi-
cally divided so as to bear two polyps. The polyps are about 0.5 mm. long, broadly fusiform, with
4—12 tentacles placed in a whorl, and surrounded below the tentacles by a thin jellied pseudohydro-
theca, which is sometimes hardly observable. The polyp stems are wholly without rings, and all but
without wrinkles, and provided with a dark-coloured, but thin perisarc, which, on account of bottom
particles appendant, convey the impression of being granulous.

The gonophores are developed into free medusae; when breaking away, they have two ten-
tacles and a well-developed, solid umbrella. The gonophores are borne individually on stems 0.2—03

min. long, proceeding from the hydranth stems; on one hydranth stem is generally developed one

>)

gonophore at a time, sometimes a couple of gonophores simultaneously.

Material:

The Faroe Islands, Sérvaag. Depth 14—16'/, fath. (on Meecela nucleus).

Certainly it is not this species that is delineated and described by the name of Perigonimus
vepens in Fauna Droebachiensis (Broch igri). A comparison with the excellent drawings of the
species with Jaderholm (1909, Taf. I, Fig. 15—16), at once shows us the difference. The species
described and delineated from the Kristianiafjord has a stiff and robust structure; its perisare is solid
and the colonies are open rhizocaulome formations; most probably the specimens in question should
have been referred to Perigonimus muscotdes M. Sars. Perigonimus repens, on the other hand, has
thin closely set, irregularly curved polyp stems. Besides, the colonies from the Kristianiafjord bear on
the hydranth stems numerous gonophores without stalks, while the few gonophores of Perzgonimus

repens are borne on distinct small stalks covered with perisare.

HYDROIDA c2

erigonimus repens is a southern species which penetrates into our seas. It has been recorded
from the Mediterranean and the west coast of France, and occurs frequently in the sea round Great
Britain and Ireland. Already in the North Sea its occurrence is more straggling. In the Danish
waters and along the coast of Bohuslin it is still rather frequent. On the coast of Norway it is not
unfrequently met with in the Trondhjemfjord, where the fauna, on the whole, bears a southern char-
acter. But only once it has been found farther to the north, at Lofoten. Semundsson (IgII) re-
cords several questionable specimens from the west and the north of Iceland. But these localities
have to be confirmed. As a new locality must now be added the Faroe Islands. The species belongs

to the litoral region.

. 200m, te = ashes ae OL? Ges ves sess tee SOOO.

Text-fig. P. The distribution of Perzgonimus repens in the Northern Atlantic (o localities needing further confir-
mation. — In the hatched region the litterature denotes a scattered although common occurence of the species).

Perigonimus abyssi G. O. Sars.
1874 Perigonimus abyssi, G. O. Sars, Bidrag til Kundskaben om Norges Hydroider, p. 96, pl. 5, Fig. 27—30.

IQII — sp. Kramp, Danmarks-Ekspeditionen til Grénlands Nordostkyst, p. 363.

From the reptant stolons proceed unbranched polyp stems, which attain a length of 1.5 mm.
The polyps are about 05 mm. long, broadly fusiform, bearing 5—8, usually 7 tentacles in a whorl.
Below the tentacles the polyp is surrounded by a rather vigorous, wide, jellied pseudohydrotheca, which
is, however, often hardly visible on the polyp wholly extended. The polyp stems are irregularly and
strongly wrinkled, and have a dark-coloured, vigorous perisare.
The gonophores are developed into free medusae, having, when deliberated, a vigorously
developed umbrella and four tentacles. The gonophores are developed on the polyp stems, to which

they are attached by a very short stalk. On the polyp stem arise one or two gonophores.

54 HYDROIDA

Material:

Greenland, Egedesminde (on Lefeta coeca).

The species has been found chiefly along the west coast of Scandinavia. It is likely to occur
much more frequently than might be believed from the scattered data. On account of its small
dimensions, and as, besides, it prefers settling on living, smaller molluscs, it too often escapes the
attention of the investigators of hydroids. Perigonimus abyssi Was been found at Bohuslan and
on the west coast of Norway, from Stavanger as far as the Trondhjemfjord, at the depth of 100

—6o00 metres. ‘On the north side of Beeren Island it has been met with at the depth of 165

+ 200 Mm.

Sseteoss 600m. t—-—-—- = 1000 M. Bienes mnccensrenetia OOO.

Text-fig. O. The finds of Perigonimus adbyssi in the Northern Atlantic,

metres (Bonnevie 1899). In Arctic regions it may occur in considerably shallower waters. Thus the
German expedition to Spitzbergen in 1898 found the species in the Storfjord at the depth of between
o and 10 metres (Broch 1909), and certainly it is the same species that is recorded by Kramp (1911),
by the name of Perigonimus sp. from the depth of 20—4o0 metres at a couple of stations of the “Dan-
mark” Expedition. To the localities previously recorded must now also be added the west coast of
Greenland near Egedesminde. — According to the data in hand, the species must be characterized as

Arctic and boreal (Text-fig. Q).

Perigonimus roseus (M. Sars) Bonnevie.
1874 Rhizoragium roseum, M. Sars in: G, O. Sars, Bidrag til Kundskaben om Norges Hydroider, p. 96.
1892 Garveia groenlandica, Levinsen, Meduser, Ctenophorer og Hydroider fra Gronlands Vestkyst, p. 13.
1898 Perigonimus roseus, Bonnevie, Neue norwegische Hydroiden.

191i Garveia groenlandica, Kramp, Danmark-Ekspeditionen til Grénlands Nordéstkyst, p. 363, pl. XXV, fig. 6.

HYDROIDA

On
mn

From the reptant stolons proceed polyp stems up to 12 mm. long, generally unbranched; more
rarely 2—4 polyp stems proceed from a common trunk, 1—2 mm. high. The polyps attain a length
of 0.7 mm., and are fusiform, with 6—12 tentacles placed in a whorl. Below the tentacles the polyp
is surrounded by a pseudohydrotheca, which it is very difficult to observe on the polyp when wholly
extended. In general it is jellied and vigorously developed. The polyp stems are, particularly in their
proximal part, irregularly wrinkled.

The very large gonophores show no medusoid structure; they are attached to the reptant sto-

lons by a short stem.

Material:

Greenland (Lille Hellefiskebanke) (the original specimen of Garveia groenlandica l,evinsen).

An examination of the original specimen of Garveia groenlandica shows no difference at all
from Norwegian specimens of Per7gonimus roseus. The species are no doubt identical. If we compare
Kramp’s drawing of Garveta grocniandica (1911, pl. XXV, fig. 6) with Jaderholm’s figure of Pe-
rigonimus roseus (tgo9, Taf. III, Fig. 7), there may, at the first glance, seem to be some points of
difference. Thus the stems of the specimen mentioned by Kramp are much shorter. But this character
proves of little significance if we compare the specimen with a larger colony, where, as a matter of
fact, the length of the polyp stems varies greatly. A greater stress might, on the other hand, be laid
on the apparently great difference between the pseudohydrothecae as represented in the two figures.
However, much depends on the contraction of the polyps and on the state of preservation, as is plainly

to be seen by an inquiry into a larger material. I have several times had the opportunity of observ-

200 m. Ae OO tooom. riactcemtconseouns¢2 OOO.

Text-fig. R. The occurence of Perigonimus roseus in the Northern Atlantic.
(In the hatched region the occurence according to the litterature is common allthough scattered).

56 HYDROIDA
ing, in larger colonies of Perigonimus, individuals with pseudohydrothecae bulging even more loosely
round the shrunken and contracted polyps than that rendered in Kramp’s drawing, while, at the
same time, in extended polyps in the same colony, a superficial view fails to notice the presence of
this formation (Broch 1o11, fig. 12). The intermediate state represented by Jaderholm is the com-
monest observed in preserved colonies. Still one point of difference might seem to remain, the chiti-
nous cup in which the gonophore, in Garzveia groenlandica, is resting when it is about to empty its
ripe contents. This cup, or rather this remnant of the flayed-off external periderm cover of the gono-
phore, is, however, frequently observed also in the female gonophores of typical Perigonimus roseus,
in which hitherto no particular importance has been attached to this character. Accordingly, we have
to include Garveia groenlandica as a synonyme under Perigonimus roseus.

The chief occurrence of the species is attached to the middle and the lower parts of the litoral
region of the boreal waters. It occurs rather frequently from Bohuslan as far as Lofoten, generally
attached to stalks of 7aéularia indivisa. However the species also penetrates far into Arctic waters,
and has been recorded from the White Sea and as far to the north as Nova Zembla. It has previ-
ously been recorded from Greenland (Jaderholm 1go9), where now also Lille Hellefiskebanke, Fiske-
nes (West Greenland), and Danmarks Hayn (Kast Greenland) have to be added to its localities

(Text-fig. R).

Family Eudendriidae.

Hydroids forming colonies, the polyps of which are provided with a single whorl of filiform
tentacles. The proboscis is capitate, placed with a narrow base on the broad polyp body above the
tentacle whorl; the stinging cells of the tentacles are small and rodshaped. Also larger stinging cells,
narrowly oval, occur, particularly in the specific stinging organs of the polyp. The stinging cells of the
tentacles are arranged in very distinctive transverse belts. The polyps are wholly naked. The endoderm
of the polyp is differentiated into two portions, an oral portion, consisting of small-nucleated, indifferent
cells, among which occur some mucous gland cells, and the proper gastral portion. The limit is formed

by the tentacle whorl. The tentacles lack a central cavity. The colonies have no calcareous skeleton.

Nearly all investigators of hydroids have distinguished the /wdendridae as a family of their
own. To this Levinsen (1892) forms an exception, considering the arrangement of the tentacles in
a single whorl round the polyp as indicative of so near a relationship to the Gowgarmvillidae that he
unites the two families into one. However, the Zudendrivdac, in their structure of the polyps, show,
as compared to other athecate hydroids, such peculiarities that we are forced to distinguish them as
a family of their own. In the first place are obvious the broad structure of the polyp body and the
capitate proboscis, placed with a narrow base above the well defined tentacle portion. In this cha-
racter the polyps bear a strongly marked resemblance to the thecaphore Campanulariudae. This like-
ness is the more interesting because, in the more delicate structure of the polyp of the Awdendridae,
several points of resemblance to the thecaphore hydroids are demonstrable. Thus the stinging cells of

the tentacles of Zudendritdae, as well as those of the thecaphore hydroids, are arranged in well defined

HYDROIDA 7
transverse belts. This peculiarity we find slightly indicated even in some Sowgainvillidae. But only
in the Luwdendriidae it has become a character plainly distinctive. Further, the endoderm in the well
defined hypostome shows the same structure as in the thecaphore hydroids, and is more strongly differ-
entiated than in the Bowgainvilliidae, the indifferent cells having gained the ascendency, and the number
of the mucous gland cells having been reduced to a minimum. Whether these peculiarities are indic-
ative of a nearer relationship between the Awdendridae aud the thecaphore hydroids, is a question
which it would here be out of place to enlarge upon.

The Ludendridac, with their frequently dimorphic development of the stinging cells, also pre-
sent a parallel to the S¢lasteridac. Besides the small rodformed stinging cells characteristic of all
Filifera, we also find in several species larger narrowly oval ones, bearing a strong resemblance to
those of the S¢y/asteridae. The latter are large, but of the same shape as the small stinging cells of
Myrtothela. We probably here face a phenomenon of convergency, the reason of which, however, at
the present stage of our knowledge of the biology of the Coelenterata, we cannot account for with
any certainty. Wherever the larger stinging cells occur in the Lwdendridae they are accumulated in

articular stinging organs.
> ce) >

Eudendrium Ehrenberg.

Upright colonies with branched hydrocaulus. The polyps are broad and distinctly set off from
the stem, which is covered with a vigorous chitinous perisare. The polyp has a single whorl of fili-
form tentacles. Above the tentacle whorl the polyp is suddenly tapering and ends into a capitate or
trumpetshaped proboscis, which is seated, with a narrow base, above the tentacle whorl. The gono-

phores are developed on normal or reduced polyps, or placed singly on the branches.

Kiihn (1913, p. 48) states that the polyp tentacles of Awdendrium “nach einander vorsprossen
und dadurch sich als Angehérige verschiedener Wirtel zu erkennen geben”. Later on (l.c p. 247) he
again mentions this peculiarity as a refutatory argument against the adoption of a nearer relationship
to the thecaphore hydroids; in the passage last quoted he apparently bases his opinion essentially on A11-
man (1872). A closer inquiry, on new material, gave no hold to the statement of Allman and Kithn that
the tentacles should appear successively. In the numerous colonies examined of Ludendrium rameum
(Pallas) and Ludendrium Wrighti Hartlaub it could be ascertained that all the tentacles appear
simultaneously. This suggests that the observations of Allman may rather depend on accidental cir-
cumstances, and that no special importance must be attached to them as reminiscences of manyrowed
tentacle-whorls of the ancestors or as proofs of a nearer or remoter relationship to the Lowgainvil-

ludae or to the thecaphore hydroids.

Eudendrium rameum (Pallas) Thompson.

1766 Tubularia ramea, Pallas, Elenchus zoophytorum, p. 83.
1844 Eudendrium ramecum, Thompson, Report on the Fauna of Ireland, p. 283.

1887 — ramosum, Bergh, Karahavets goplepolyper, p. 332.

The Ingolf-Expedition. V. 6. 8

58 HYDROIDA

1908 Eudendrium caricum, Jaderholm, Die Hydroiden des Sibirischen Eismeeres, p. 5, Taf. I, Fig. 4,
Mat uly Ec aer.
IQII — rigidum? + Eudendrium ramosum, Semundsson, Bidrag til Kundskaben om de is-

landske Hydroider, p. 74—75.

The strongly and irregularly branched colonies have a fascicled main stem, and attain a height
of 200 mm. The small branches are annulated immediately above their rise from the mother branch,
but are elsewhere smooth. The polyps have about 20 tentacles. There is no particularly developed
ring of stinging cells round the tentacles or the polyp body. The colonies have no particular sting-
ing organs.

The gonophores are styloid. The male gonophores have 2—4 chambers and are seated round
the base of fully developed polyps. The female gonophores are pear-shaped, and are borne on the
bodies or the hydrocauli of polyps that may either be fully developed, or somewhat smaller than the

sterile polyps, or entirely reduced. The spadix is unbranched.

Material:

‘“Wngolk’ St2n S8:or N. lat. gac45 long W. Depth 1330 fath. 2°4 C

_ - 31. 66°35’ - - 55°54 — - — 88 — 16 -
SR Gre ee) Vichy So Soot oA Str Ole
Greenland sDayiseotraitescnitocw soe es amici crim a renee eres eK Depth 80—100 fath.
lentye land wwlasteGiecenlatidae carrier titer reer icetetr oie _ 20 —
Cape Mobi scrrtvser sete see cists ost ea ro ee OE erate: — 7 —
Teelandosmuilesswest of [celandescce gascmer ciets cite eerie serie — 22 —
Stylacish olin tee eersc mee tener eon Cee en Te icteric eases — 20-30 —
Faxebugt, 16 miles N.E. of Akranes (“Zudendrium ramosum”) — 26—30 —
Vestman Islands (“Ludendrium rigidwm 2”) ......... eevee — 30 —
Gheskaroelslands:eStokkene2 enol miles 9:22 ier ecm vette eile — 5 —
Sabino dep rere reicee maria dcdcrs CA cetioic teen 6r°15' N. lat. 9°35’ W. long. -- 872 m.
STD) etna: Sgeasteepe ssi ces olusliatete pe ences ke tereae ke = 61°40’ - - 7°40! - — — 135 fath.
Store Fiskebanke (Large fishing-bank) 57°7' - - 2°40’ K. — = 37

The Kara Sea, “Djimphna”.

This common northern species has, no doubt, frequently been confused with the southern spe-
cies Ludendrium ramosum (Lin.), which, in fact, is rather rare in our northern seas. Assuredly enough,
nearly all the statements of the occurrence of the last-mentioned species in Arctic waters, are to be
regarded as referring to specimens of Luwdendrium rameum, the appearance of which varies greatly
indeed. It has already been pointed out by Kramp (1911) that the species Ludendrium caricum from
the Russian polar expedition, described by Jaderholm (1908), is, in fact, founded on specimens of
Eudendrium rameum. Surely enough, it is the same species which is recorded by Bergh (1887) now
as Eudendrium rameum and Eudendrium ramosum, now as Eudendriwm sp.

The species has a circumpolar distribution, and appears, from the statements of literature, to be a

HYDROIDA 59

rE eS 600m. tee ee 1000 M. stawssavssemseouss SOOM Te

Text-fig. S. The habitat of Zudendriuwm rameum in the Northern Atlantic.

perfect cosmopolite. It occurs frequently everywhere in the middle and deeper parts of the litoral region
of the northern seas (Text-fig. S), and may, exceptionally, as in the “Ingolf” st. 21, also penetrate far

down into the abyssal region.

Eudendrium ramosum (Linné) Ehrenberg.
1758 Tubularia ramosa, Linné, Systema nature, ed. X, p. 804.

1834 Eudendrium ramosum, Ehrenberg, Beitrage zur physiologischen Kenntnisse der Corallenthiere,

p. 296.
nec 1887 -— — , Bergh, Karahavets Goplepolyper, p. 332.
nec IgII = — , Semundsson, Bidrag til Kundskaben om de islandske Hydroider, p. 74.

The strongly branched colonies show an almost quite regular, alternating arrangement of
the small branches. The main stem is fascicled. The small branches are annulated above their rise
from the mother branch, but are elsewhere quite smooth. ‘The polyps have about 20 tentacles. The
stinging cells are not accumulated in any particular main ring round the tentacles or the polyp body.
The colony has no particular stinging organs.

The gonophores are styloid. The male gonophores have 2—3 chambers and are seated round
entirely atrophied polyps with short hydrocauli. The female gonophores are pear-shaped and borne
on the bodies or on the stems of polyps which are either fully developed or somewhat reduced as

compared to the sterile polyps. The spadix is unbranched.

Material:

Southeastern Iceland: (H6rring) 1898. — Depth 52—49 fath.
8*

60 HYDROIDA

The species Eudendrium ramosum (Pallas), Budendrium rameum (Pallas), and Ludendrium race-
mosum (Cavolini) are very nearly related to each other, and sterile colonies of the three species are often
hardly distinguished with certainty. While in Eudendrium rameum the male gonophores are borne on
polyps fully developed, they are seated, in Ludendrium ramosum and Ludendrium racemosum round polyps
wholly reduced. This conformity of the two last-mentioned species, the homogeneous structure of their
colonies, and several other features common to them, which struck me during my inquiry into the Adriatic
hydroids (1912), really led me to consider, though with some doubt, Ludendrium racemosum as a synonyme
of Ludendrium ramosum. ‘This supposition, however, is hardly right. By the liberality of Dr. C. Lehnho-
fer at Innsbruck I have afterwards had the opportunity of examining more closely unquestionable colo-
nies of Ludendrinum racemosum from Triest, and of recognizing in these the characteristic criteria distin-
guishing this species from Ludendrium ramosum. Occasionally are found developed in the polyp of Zz-
dendrium racemosum peculiar organs which are not traceable in other species of the genus, and which, like
analogous organs in other hydroids, have to be designated as “nematophores” (cp. Weismann 1882).
Elsewhere the presence or the absence of these formations is looked upon as a generic character among
the hydroids. But this view is here hardly justifiable, as in Ludendrium racemosum the nematophores occur
quite irregularly and are rather rare; in some colonies they are even entirely wanting, and such colonies,
when sterile, or when only male individuals occur, cannot be distinguished with certainty from Ladendrium
ramosum. — The other distinguishing mark between the two species is the spadix of the female gono-
phores. While, according to the descriptions in hand, the spadix of adendrium ramosum is unbranched,
that of Ewdendrium racemosum is, on the contrary, bifurcate or divided into three branches, embracing
the ovum like a claw (s. Broch 1914 Stylasteridae p. 24, Text-fig. I) I regret that I have not succeeded
in getting hold of fertile female colonies of Auwdendrium ramosum, so as to be unable to give a draw-
ing, from new material, of the female gonophore of this species.

From the statements above it is clear that Awdendrium ramosum has most probably been
several times confused with Ewdendrium racemosum. On the other hand, as I have earlier pointed
out, a confusion with Hudendrium rameum, particularly from the northern seas has also often taken
place, and the geographical data presently in hand as to Ludendriwm ramosum are, therefore, of most
questionable value. A closer inquiry into the colonies from Faxebugt (Iceland) recorded by Se munds-
son (19011) as Ludendrium ramosum, shows that we here really face typical Audendriwm rameum.
However, the single specimen of the species which is in hand, shows us that in warmer layers of
the Atlantic it may occur as far to the north as Iceland. The occurrence of the species in the northern

Atlantic regions, however, has yet to be more closely accounted for.

Eudendrium Wrighti Hartlaub.
1859 Ludendrium arbuscula, Wright, Observations on British Zoophytes, p. 113, pl. 9, fig. 5—6.
1905 - Wrighti, Hartlaub, Die Hydroiden der magalhaensischen Region, p. 547.
The strongly and irregularly branched colonies have a fascicled main stem, and attain a height

of 60 mm. ‘The small branches are annulated above their rise from the mother branch, but are else-

where smooth. The polyps have a large number of tentacles. The tentacles have no particularly

HYDROIDA 61

distinct main ring of nematocysts. On the other hand, there is round the polyp body, at its base, a

distinctive girdle of large stinging cells. Otherwise, the colony has no particular stinging organs.
The gonophores are styloid. The male gonophores have two chambers with a well marked

accumulation of stinging cells distally, and are densely clustered on short stems perpendicularly

placed on the trunk. Female gonophores are unknown.
Material:
The Faroe Islands: Trangisvaag, on roots of Lamznarta.

The species was first described by Wright (1859) by the name of Eudendrium arbuscula from

the Firth of Forth. However, another Hudendrium had been previously described by d’Orbigny

soesseseceseceeeeee 200 M. aaa wow e 600 A. treme 1000 M, sasciusscenstamss 2 O00 (77.

Text-fig. T. The occurence of Zxdendriwm Wrighti @ and Eudendrium annulatum a in the Northern Atlantic.

(The vothed coastal parties denote a scattered occurence of Ludentium Wright according to the litterature).

(1839) by the name of 7wdularia arbuscula from Patagonia, and even though it will be questionable
whether the species of d’Orbigny can be reidentified, we are no doubt right to follow Hartlaub
(1g05) and abandon the name of arbuscula for the northern species. Here we, therefore, adopt the
denomination of Hartlaub, Ludendrium Wright.

Eudendrium Wright? is an absolutely littoral species, the occurence of which seems to be restricted
to the zone of the Laminaria. It occurs quite frequently from Bohuslan as far as towards the Trond-
hjemfjord, and it is peculiar, therefore, that its female gonophores have not yet been pointed out. The
species is quite common at the British Isles (s. the Text-fig. T), and it has also been recorded from the
Mediterranean. udendrium Wrighti is, therefore, likely to be characterized as an Atlantic species of
southern character, which is able to penetrate into the northern seas as far as the Trondhjemfjord.

The Faroe Islands have now to be added to the localities where the species has been found.

62 HYDROIDA

Eudendrium annulatum Normann.,
1864 Eudendrium annulatum, Norman, On undescribed British Hydrozoa, Actinozoa, and Polyzoa, p.
83, pl. 9, fig. I—3.
The strongly and irregularly branched colonies have a fascicled main stem, and attain a height
of 100 mm. All the smaller branches are densely annulated everywhere. The polyps have 16—20
tentacles. There are no particular accumulations of stinging cells on the tentacles or on the polyp
body, and the colony has no particular stinging organs.
The gonophores are styloid. The male gonophores have one chamber with an accumulation of
stinging cells distally, and are densely grouped on short stalks perpendicularly placed on the stem.
The female gonophores have an unbranched spadix and form grape-like clusters round polyps entirely

atrophied.

Material:
Greenland: Sukkertoppen (without particular data).

Iceland: Vestman Island, on the stems of Z2delaria imdivisa.

Eudendrium annulatum seems to occur rather sparsely, but apparently on the whole prefers
the littoral parts of the boreal seas. However, among the localities of the species are also recorded
the Cape Verde Islands (Quelch 188s), and with some doubt Cape Town (Ritchie 1907). On the
west coasts of Scandinavia the species has been met with here and there from Bohuslan as far as
Vadsé, and it even occurs in the Murman Sea. It has been found near Jan Mayen and the Shetlands,

and specimens occur from the south of Iceland and from West Greenland.

Eudendrium capillare Alder.
1856 Eudendrium capillare, Alder, A notice of some new Genera and Species of British Hydroid Zoo-

phytes, p. 355, pl. 12, fig. g—12.

The strongly and irregularly branched colonies have a simple unfascicled main stem, and
attain a height of 30 mm. The branches show a few rings immediately above their rise. But else-
where they are smooth. The polyps have 20—30 tentacles. There are no particular accumulations of
stinging cells on the tentacles or on the polyps. The colonies have no particular stinging organs.

The gonophores are styloid. The male gonophores have two chambers with an accumulation
of stinging cells distally, and are placed in a whorl round entirely atrophied polyps or, more rarely,
round strongly reduced polyps, the stems of which rise from the hydrocaulus or the hydrorhiza. The

female gonophores occur in the same manner; they are pear-shaped with unbranched spadix.

Material:
Greenland: Store Hellefiskebanke ... Depth 28 fath.
Iceland: Stykkisholm ... Depth 30 fath.

The Faroe Islands: between Nols6 and Ostnees ... Depth 100 fath.

The specimens from the “Store Hellefiskebanke” offer a great interest, the male gonophores

HYDROIDA 63

otek he @ aera 5 600m. Sep uan's sos em sams fooom. SS a IL

Text-fig. U. The distribution of Zudendrium capillare in the Northern Atlantic.
(The hatched coastal region indicates a scattered occurence according to the litterature).

being borne by diminutive polyps. It accordingly appears that the fertile polyps of the species are
not always wholly atrophied, as has hitherto been generally supposed.

The distribution of Audendrium capillare is extremely wide, almost quite cosmopolitan. It very
frequently occurs in the northern seas (Text-fig. U); however, already in the Norwegian Sea and
along the west coast of Norway its occurence becomes less frequent, and it does not penetrate very

far into the Arctic regions. The species belongs to the middle parts of the littoral region.

JN (28)

“I

10.

Il.

LITERATURE

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HYDROIDA 65

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The Ingolf-Expedition. V. 6. 9

HYDROIDA

So.

Sr.

(os)
(os)

89.
go.

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Plate I.

Fig.

Plate I.

Nematocyst from the tentacle of A/onocoryne gigantea. Delafields haematoxyline — Iron
ammonium sulfate. 175°/,.
Nematocyst from the tentacle of Coryne Lovént. Boehmers haematoxyline — Iron ammonium
sulfate. 175°/;.
Nematocysts from the tentacle of AZyriothela phrygia, a: of the general, ovoid type, b: of
the rarer, narrow type. Delafields haematoxyline — Iron ammonium sulfate. 175°/,.
Nematocyst from the tentacle of 7wébularia indivisa. Delafields haematoxyline — van Giesson.
175°/,,
Nematocyst from the tentacle of Clava multicornis. Delafields haematoxyline — Iron ammo-
nium sulfate. 1759/,.
Nematocyst from the tentacle of Bowgainvillia ramosa. Delafields haematoxyline — Iron
ammonium sulfate. 175°/,.
Nematocysts from Ludendrium Wrightt, a: small type from the tentacles, b: larger type
from the belt of stinging cells at the base of the polyp body. Delafields haematoxyline — Iron
ammonium sulfate. 175°/,.
Myriothela phrygia; mutilated specimen from the “Ingolf” st. 125. 2/;.
Flydractinia echinata,; spines from the Greenland specimen. © /,.

— — specimen from Greenland with extraordinarily large spines. 2/;.
FHydractinia carica; spines from the type specimen. °°/;.
Flydractinia Sarsit; spines from a specimen from Godthaab harbour, wrongly labelled

“Podocoryne carnea’’, °/;.

Broch: Hydroida. Plate I.

The Ingolf Expedition, V. 6.
et ety
fie A
| L
“ig : A ea
5) a ; ;
,
\ j ‘
| | |
cr DA
re 9
A
6
LES

| j i }
| i
10

11

a

Ljustr. A. B. Lagrelius & Westphal, Stockholm

Hj. Broch del. et phot.

. 7

nun © i By, magi, a
‘a a

Plate Il.

Fig.

13.
14.

Plate Il.

Coryne Loveni; specimen from Bjarkéy, Northern Norway. 7°/;.

Corymorpha groenlandica; one of Allmans type specimens of Monocaulus groenlandica show-
ing the young blastostyles as mere sacs without any trace of the single gonophores. 3°/;.
Corymorpha groenlandica trom the Davis street, wrongly labelled “Amalthea tslandica’’.
Nat. size.

Tubularia pulcher. Gonophore of one of the type specimens of “Auliscus pulcher’’. ©/s.

/

Merona cornucopie on Cardium sp. from the Faroe-islands. 3°/;.

The Ingolf Expedition, V, 6.

C
‘a
val
2
Ce
aoe
f
{
\
Get y
\ \
Se ‘
/ MY
frat
kav}

Hj. Broch del. et phot

Broch: Hydroida.

Plate

17

We

'

6 ss ‘i ,
ety a
me

ibe eG Oiler iE XeRTe Dee ih@an

r895—189.6,

THE LOCAJ ITIES, DEPTHS, AND BOTTOMTEMPERATURES OF THE STATIONS

used

Depth | | Depth | ’ Depth
Station Lat. N. Ponca in Bottom-| Station ace Nee ar | in | Bottom- Station Tat he | one we | in Bottom-
Nr. Danish | temp. | Nr. | | Danish | temp. Nr. Danish _ temp.
fathoms | | fathoms | fathoms |
_ <= =i = = —— = = —— a
I 62° 30’ Soom 132 729 | 24 63° 06’ | 56° 00’ 1199 2°4 45 | 6712.32 Gw43@ OAs Alyy,
2 63° 04’ 9° 22’ 262 Son | 25 308308 54025) 582 323 46 | 61° 320 Tro13 6) 720 2°40
3 63° 35’ | 10° 24’ 272 0°5 | 63° 51’ | 53° 03' 136 | 47 | 61°32’ | 13°40 950 3°23
4 64° 07’ Lor L2/ Dain 2°5 || 20 63°57" le 52° 41! 34 | 0°6 48 | 61° 32’ Ie ofa 1150 | BOT
5 64° 40’ 12° 09’ 155 | 64° 37’ 54° 24’ 109 49 62° 07’ | 15° 07’ 1120 2°91
6 63° 43' | 14° 34’ | go 7°0 | 27 | 64°54’ | 55° Io’ | 393 3°8 50 62° 43° | 15° 07’ 1020 3°13
7 63013" age ebia 600 | 4°5 | 28 | 65° 14’ 55° 42’ 420 | Bo5 51 | 64° 15 rAvoo! 68 7222
8 63° 56’ 24° 40’ 136 6°0 200 65-9346 a 54o Sr 68 | 0°2 52 6301577 | ic ae) 420 | 7°87
9 | 64°18’ 27° 00’ 295 5°8 | 30 66° 50° 54° 28’ 22 | 1°05 53 63°05! 15° 07’ 795 3°08
10 64° 24’ | 28° 50’ 788 325, | 31 COM asa sSo54 | 88 | 1°6 54 63° 08’ | 15° 40 691 3°9
Il 64° 34% ||| 31° 12’ 1300 16 32 66° 35° | 56° 38’ 318 3°9 a | 63° 33° 15° 02 316 5°9
12 64° 38’ | 32°37’ | ogo | 093 33) | 672°57° || 55% 30) 35 | a | o 64° 00’ | 15° 09’ 68 7°57
13 64° 47' | 34° 33’ 622 | 3°0 || 34 6597 7'all|p5Acer 7 | 155 57 63° 37° | 13°02’ 350 3°4
14 | 64°45’ | 35° 05" 176 4°4 35 65° 16’ | 55°05’ | 362 | 3°6 | =58 «=| 64°25 12° 09’ 2r1 0°8
15 66° 18’ 25° 59’ 330 —0°75 | 36 | 61°50" | 56° 21’ 1435 1°5 59 | 65° 00 Tce Os 310 |—o°rX
16 65° 43’ 26° 58’ 250 6°! | aii | 60° 17 54° 05’ | 1715 1°4 | 60. | 65° 09 T2o27) 124 | 0°9
17 62° 40’ | 26° 55’ | 745 3°4 | 38 59° 12° 51° 05' | 1870 Do | 61 | 65° 03' | 13° 06’ 55 o0°4
18 61° 44’ | 30° 20' T2135, | 390° | 39) | (62° 00% ||) '22°°38’ 865 | 2°9 625 I 63978) | oem! 72 7°92
19 60° 29’ | 34° 14’ 1566 2°4 | 40 | 62° 00° 21° 36’ 845 | eS) 03 | 62° 4o’ 19° 05’ 800 4°o
20 58° 20’ | 40°48’ | 1695 | 1°5 | 4I | 61° 39’ 17° Io 1245 2°o 64 62° 06’ 19° 00 1041 Sor
21 58° o1 | 44° 45’ 1330 | 2°4 42 | 61° 41’ 10° 17" 625 0°4 | 65 61° 33’ | 19° 00’ 1089 3°0
22 58° 10’ | 48° 25' | 1845 1°4 | 43 61° 42’ 10° II 645 0°05 66 61° 33’ | 20° 43' 1128 Bo
23 60° 43' | 56° 00’ “Plankton Net 44 | 61° 42’ 9° 36" 545 | 4°38 || ~ 67 61° 30’ | 22° 30° 975 3°0

Depth | Depth | | Depth
Station] rat. |zong.w.|__i2 |Bottom-| Station) 124 w. |nong.w.| _™ |Bottom-| Station) 744 n. |Tong. we HE ORO
Nr. | Danish | temp. Nr. Danish | temp. Nr. Danish temp.
| fathoms | | eee ; | fathoms
] Tl Tan | | 7 21 | aera| | i
68 62° 06 220830) 843 | Bonu all g2 64° 44' 32°52’ | 976 1°4 118 68° 27’ | 8° 20' | 1060 —r1°o
69 62° 40’ | 22°07, |) 589 3°9 | 93 64° 24’ | 3504" 767 1°46 | 11g | 672753) | LOS 19; | 1010 —I1°o
70 (SrMeey |) Baaroly |) acyl || 7/8) | 94 | 64°56’ | 36° 10’ | 204 Act Bl e208 BI O7o20) | LTO 21 885 | —r1°o
71 63° 46’ | 22° 03' 46 | | 65° 31’ | 30° 45’ 213 121 | 66° 59’ HA 151 529 | —0°7
72 63° 12’ | 23° 04" 197 627 || «95 65°74" 1) 20°30) 752 AP 122 66° 42’ 14°44’ | 115 1°8
73 62° 58’ | 23° 28’ 486 5O5 | 96 65° 24’ | 29° 00’ 735 To2 123 66° 52’ | 15° 40 | 145 2°0
74 62° 17’ 24° 36’ 695 4°2 | 97 .| 65° 28’ 27° 39° 450 BER 124 67° 40° 15° 40’ 495 —o°6
6m 57a 25535 761 98 650387) 26227) 138 5°9 125 68° 08’ 16° 02’ 729 | —o°8
61° 28’ | 25° 06’ 829 | 99 GGIiey || WE Gey 187 6°r) || 126 67° 19’ TS 293 | —0°5
75 61°28" || 26°25; 780 4°3 || 100 66° 23’ T4° 02’ 59 0°4 127 662g 24 e 2021057 | 44 5°6
76 60° 50’ | 26° 50° 806 | 4° | ror | 66° Dey T2°%057 || 537) | 027, 128 66° 50’ | 20° 02’ 194 | 0°6
77 60° 10’ | 26° 59 951 3°6 | 102 66° 23’ | 10° 26 | 750m | On9 129 | 66°35’ | 23° 47’ 117 6°5
78 60° 37° 27Cn5 24 799 4°5 | 103 66° 23’ 8° 52’ 579) || —o26) || go 63° 00’ 20° 4o' 338 6°55
79 60° 52’ | 28° 58" 653 | 4°4 | 104 66° 23! OSs ey || ar 131 63° 00° | 19° 09! 698 | 4°7
80 612102! || 29° 32° 935 | 4°o | 105 65° 34’ Gp a! | 762 | —o°8 132 63° 00’ | 17°04’ | 747 4°6
81 60S 447 272/00; 485 6°r |} 106 65° 34’ 8° 54’ | 447 —o°6 133 63° 14’ TL 244 230 Do2
82 Gross 5a 27 207 824 A°1 | | 65° 29’ 8° 4o’ 466 134 62° 34' 10° 26’ 299 | Ao
83 62° 25’ 25°30) | OL2 | Bos | 107 65° 33’ 10° 28' 492 | —0°3 135 62° 48’ 9° 48’ | 270 0°4
| 62° 36’ | 26° o1’ 472 | 108 65° 30’ 12° 00’ 97 | yey 136 (Or? |) Goi | 256 4°8
62° 36’ | 25° 30’ 401 | 109 65° 29’ | 13° 25' 38 | Te Seal 3 7 63°14 ||" 823re | 2078 e076
84 62° 58’ Digna 633 4°8 | 110 | 66° 44’ rate ee 781 | —o°8 138 63° 26’ 756% 471 —0o°6
85 (Gye! | | OO elias 170 | amit il) yf ak 8° 48’ 860 | —o°g | 139 63° 36’ | GD akoy joz | —0°6
86 65° 03'6 | 23° 476 76 | 112 | 67° 57’ 6° 44’ | 1267 | —I°r 140 63° 20! | 6°57’ 780 | —o°9
87 65° 02’, | 23° 562 | 110 ees | 69° 31’ 7° 06' 1309 —1°0 141 63° 22’ 6° 58’ 679 —0°6
88 GASES Siaai2Aca2 by 76 6°9 | 114 | 70° 36’ 720% 773 | —1°o | 142 63° 07’ 7° 05' | 587 —o°6
89 64° 45’ | 27° 20’ 310 8°4 | 15 70° 50° 8° 20° 86 | O°! 143 62°58) {7209/1 e885) 024.
go 64° 45’ 29° 06’ | 568 4°4 | 116 | 702105; | 8°26; 371 —o°4 || 144 | 62° 40’ | 712’ | 276 | 1°6
gI 64° 44’ | 31° 00" 123 Om es oat eT 7 | OO esl iaull Oe 230 | 1003 | —I°o |
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