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VOLUME VI.

3.

PORIFERA.

(PART IIL)

DESMACIDONIDZA: (PARS).

BY

WILL. LUNDBECK.

WITH 11 PLATES.

COPENHAGEN.
PRINTED BY BIANCO LUNO.

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"Ready from the Press Avril the 1 r910,

CONTENTS.

Desmacidonide.

; Page Page
REIN olan LE. ocatdiy Viatd 08 t sabes a's wee sis 9 = I. | Hymedesmia longistylus n.sp................-...- a Ae
NB 2 as ei viaiy Cia ee OA ainlaid' ses se cols bei ome nS - MECHA OW. os op sas aCe spans eee et en 67.
Oy SES ROE RE AORN rie fiche ara ae Sa Zs -— MRM 5 BIS 66. es nites Sane use oe oa peeks 69
PROM MINM Syke on Cale wLitld ony cho:S cig Patera nce planets a — Darien TONE vos acy bans asin a Geen Heats 71
Pee BORO Ys OREM oo vic so wesc ight ps ce I — oP ACT NRE Re ara sy ean pie Alay £
leer ESS St ERROR OCR Se ar one a: - DRRCKER MMB 600-5 daiwa ov Capes A ees 74.
— appendiculatum Cart.................. Y ( — TOSWABE GIR? Th, OP. 55ers iar « 35-0 er 74.
o Byes Ci OMIM cose ees ofe sme ti _ BOWEtRAUET 1. OD. oF ood venice aise ek taon Pues 75-
PEMROU IRIN ee ocd res wir SA ic )0\ ain bia dao wile a sos cor 13. _ SEMMCAEEY CMIG kG as cals) wae enaies ee ceus 77-
_ PUM SAERUE Scotts, inte Wis wiaycotoree 3.5 ws 14. — INPRTMCHECIAOA NGG) 5 ccs < cy sc oso eats 78.
— COMMONS ODE 5c pees «0s ds 5 32's,s's ='p 16. _ SPUD OTUATS A, BD. via co arte desk oso we KRG oe 80.
SSE ae alae ear Werielhs Unis nates 18. — PPRIID ID: Te Bia.) 5 ning GS s Bed ee nn rele oon 81.
— permeate. O; Schmidt oi. eee as 18. -- Orne Or Schade. i oso cewc saa ves wieele se 83.
Ss MRC RMN is igs bien a 4 a an laceanei nine dye 20. _ POMAPM AY ERM ghia bag dle a. sgiiie dw ature waite 84.
NIE tea alas Sites aan 8 aye.clestnie W's ess 22. _ Siifern: O; Sebwside i. sine a ee 86.
— PREIS MM HG ichitrenre nari Sisienea ce cr haw 22. - MROMG BEMIS ilar seo gees ssa ee elie wale 88.
coe ci) Mesa sya edu AGES ania Pah Rte Ac ea Sa oe ae 29. — CE OP Seana aR OP ee et ERE SPR a go.
= Pn ET Ss “4 ARORA a Ret ra Cor ae oe 30. _ RECTOR BID ce os oc dig ae sale alse. oe Saw nye gl.
— Or IE Re | SRA, Sa eae ere ee Die eae 34. — PUBCON DEB is. 5 330 sink avisieeladss eines 92.
Set ae ORME EOS 8 cide eds. s 9 53a or oiond Sraiepy «0b += 36. ~ PUM BB. Dees NaN. Galas dees 94.
RRRG ORANG reo aso oan Rina is ais Min sida ls va raj eins Mgawiale dca 39- —_ COMBA MINGH MAD 5 is ice es Sah cidieele eas 95-
oT ES eS a ae RE IRR eg ea SE 39. = PMC ODs..4 Gi dlske sue ne ate ee elas 96.
— TR OMIM RODE. 00s Siiicsicg howe wie ool oe 42. _ RAMMEP IN STED: T GINS ais. Secale wip 8 sea aes ae 97-
a MMMM SRE GEN cic Ard. of siete Be plaid vere emiaid bela 44. _ MCI ORAS LOMMR aii as eo aes pc ca oes oie 98.
- MEO EM iciticidic.co eae sss cba calegles 45- _ CPUVIM UE NLEDS 5. oa sia eee ee see t eS 100.
a PRT Se MON orice tsi) S oes tele sie) Fee oni 46. - PRPC DOW ops o isro oe ale olin aaeweeo es IOI.
-— COST ORT uP eR RSS ee ea Oo 47- _ PIMA Th: BD. ele gia os. bao ae ee eek yess sk 104.
_ MES VICIIEIA TBD iy: 6.0 <s seo viss h ss sie elses 48. _ MONGUTUS MEWPT oie sok sok wks k Ge os dase este 105.
_ SRO Tea aS oie neers ae te anise diene ¢ 50. _ MOHMUAEA MBPs 5 i ccisd oe cigs meen cnels ped eee 106.
— Spree fe BO Le oak 8 region 51. — rE Dh Bic 0-5 ip os aes sete ares ee te 107.
_ SRTATCUUA TEBE oo occ 570s Sos sine pietelodst 52. oa NSSUESUR ERE Ay MIN es Calg. 3 cle a alo ik wey nieew- ea we 109.
— SEAS TBP OT a area dlgtnine si 53 — eaperOneN a MBN sc. io on oye ees ew Cems ea es IIo.
— UTERINE BBs in wins 3 Gis aad nee 3s 55. | Table of the species of Hymedesmia ...............-... TI2.
- GEE: TBP a alse daw Ma Ses ws Ras e e es Mier lr Sa WINEMORCORAL Corea. Cues Naik d Meeln Coe aden sacle Roe cas 116,
_ BUG IREI TMD sas fecal eetctn eis sis 40.2 38 57. -- SRTORIORS, SBD oo 3S cate ivoenan See slene es 117.
= WEFMCOME DBDs o:6 on oir Reese ve em dee 58. _ COTW PENET T. Ee oc Secs y ohm ee sas 118.
— PrOocmmMibeta Wisp. ea... Fes ak ne 60. —_— UREN ANB 6) oe iste on are ce ee wee 119.
_ Petiotata ae Oe ct. se eee 61. — PRIMERS 2 OD 8 Se clas gece eeee ewes 121.
= Tg EYE See ee oe 62, | ECPUcennaeee eee Mba eiiitsy Wes sale Wrotiecve discee sies-ch sw nets 122.
- PUAty CHAN Me Otis rs see sai hens 63. assimilis 11 Spore, cactur eer eeuomeay pacar e cea a 122.

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Porifera.
Ill.

By

William Lundbeck.

(Fam. Ill. Desmacidonide.)
(Subfam. 1. Mycaline.)
(Group 2. Myxilles.)

Tedania Gray.

Of various shape, incrusting, massive, erect and leaf- or cup-shaped, or cylindrical, or finaliy
more or less digitate and branched. The skeleton a more or less diffuse reticulation, generally multi-
spicular, more rarely partly or quite unispicular. Spongin generally (or always) present, as a rule to
a slight degree, sometimes more richly. The dermal skeleton as a rule formed of erect bundles of
dermal spicules, sometimes also spicules lying horizontally in the dermis; tt ts sometimes strongly devel-
oped, sometimes weaker, with relatively few spicules. Oscula scattered, sometimes on the apex of tubes
or papille; pores scattered or on the apex of papille or otherwise definitely localized. Spicula: mega-
sclera: the skeletal spicules are smooth styli, the dermal spicules diactinal, tylota, tornota or strongyla,
sometimes with slightly spined ends; microsclera only one form, rhaphides with unequal ends, finely

spinulous, in dragmata or scattered.

1. T, suctoria O. Schmidt.
Pl. I, Figs. r—5, Pl. IV, Fig. 1.
1870. Tedania suctoria O. Schmidt, Grundziige einer Spongienf. des atlant. Gebiet. 43, Tab. V, Fig. 11.

1875. Tedania increscens O. Schmidt, Jahresb. d. Comm. zur wiss. Unters. deutsch. Meere in Kiel fiir

1872—73, IIS.
1882. Tedania suctoria, Vosmaer, Niederl. Arch. f. Zool. Suppl. Band I, 42, Pl. I, fig. 24, Pl. III, figs. 83—88.
1885. — — , Vosmaer, Bijdr. tot. de Dierk. 12‘ Afl. 3%¢ Gedeelt. 22.

1892. Tedania conuligera Topsent, Résultats des camp. sc. du Prince de Monaco, Fasc. II, 79, Pl. I, fig. 16.
1903. Tedania increscens, Thiele, Arch. fiir Naturgesch. 1903, I, 380. Taf. XXI, Fig. 9.

1904. Tedania suctoria, Topsent, 1. c. Fasc. XXV, 176.

1909. — — , Lundbeck, Meddel. om Gronland, XXIX, 443.

Incrusting, massive, or more erect and sometimes somewhat branched. Surface more or less
richly beset with papille and diffusely hispid. The dermal membrane somewhat solid, its skeleton weakly

developed, consisting of bundles of dermal spicules, partly erect, partly more horizontal; also scattered
The Ingolf-Expedition. VI. 3. i

Ae Meals 3 PORIFERA. III.

spicules. Oscula few, lying on special papille, pores on the summit of other papille. The skeleton a
mainly polyspicular, diffuse and irregular reticulation, Spicula: megasclera: the skeletal spicules styl
a30—068™", the dermal spicules tylota o-25—047""; microsclera one form, finely spinulous rhaphides
with unequal ends o'053—0'50”.

Of this species we have a very rich material from the whole Ingolf territory. The individuals
may have a very different aspect, but as a rule they are characterized by having a greater or smaller
number of wart-shaped papille. In the typical and fully developed shape the species is massive, more
or less roundish, lumpy and in greater or smaller. extent attached to a substratum. From this roundish
shape the species may show many variations, it may be elongated and assume a somewhat erect
shape, and it may be club-shaped, lobate, compressed or more or less branched. The latter shape is no
doubt due however, at all events partly, to the fact, that it incrusts, or originally has incrusted, branched
Hydroids or Algze, but in this case it seems to be able to continue its growth out in free, branched
forms. The smallest and youngest specimens are incrusting and from this crust-shaped origin it may
then by and by grow up to the massive shape, but it may also persevere as a crust and as such
reach a considerable extent. In our material it is found growing on stones, various Bryozoa, worm-
tubes, Algze e. g. Ptilota plumosa, the specimen on this is branched, and finally on a crab. The largest
specimen, which is of an elongated shape, has a length of about 40o™™; a massive, tuberous specimen
is 30™" in diameter; the incrusting specimens are generally small, but may, as said, reach a greater
extent, up to 25™" with a thickness not much over 1™,. Topsent mentions and figures (l. c.) larger
specimens, up to an extent of 9°™, of typical massive shape. The colour (in spirit) is yellow or
whitish yellow. The consistency is of medium firmness and somewhat elastic. The surface is more
or less densely beset with papillz, otherwise it is, when examined with a lens, somewhat diffusely
hispid. In the larger, massive specimens the papille are generally present in great numbers, and the
same is the case with the larger crusts; in the small incrustations the papillae may be few or indistinct.
The dermal membrane is a very solid and easily separable membrane; outermost it shows a thin, film-
like layer, which under the microscope is seen to be curled or folded. It would seem that this layer
in the living sponge is adhesive, as it generally shows adherent foreign particles such as diatoms in
great multitude. Oscula and pores: as mentioned the surface is more or less richly beset with papillz
which are specially well developed in the larger specimens, while they are less developed in the
small specimens. The papillz are conical in their lower part, the upper part being cylindrical. They
are seen from quite small warts up to a length of 4™™; they are compressed and have a breadth up to
15™™, These papillae must be supposed to he partly oscular- and partly pore-papille, the fact is,
that they show some difference. Some few of them are simply hollow and show an opening in the
summit, their wall is thin and supported by dermal spicules which are more or less distinctly arranged
as longitudinal bands; these papillee must accordingly be taken to be oscular-papille. By far the most
of the papille have another structure; they are hollow like the oscular-papille, but from the wall spi-
cula fibres stretch into the lumen; these fibres may be branched upwards and terminate in the upper
surface of the papilla, which is thus supported by a number of spicular pillars. All the spicules in
these fibres are dermal spicules. The papilla show no opening at the summit. These papillae must

be supposed to be pore-papillz, and probably the pores are found at their ends. The pores I have

PORIFERA. III. 3

not seen, but as the papillae are nearly always somewhat contracted, it was also not to be expected,
that the pores should be visible. The two kinds of papilla are often recognisable already from their
outer shape, the oscular papille being somewhat evenly conically pointed, while the pore-papille are
more cylindrical in their outer part and have a stubby or cut end. Often, however, the papille are
so strongly contracted, that it is not possible to distinguish them from each other so directly. In the
dermal membrane outside the papille no pores were found. The structure mentioned of the papille
has not been described hitherto, only Schmidt has some remarks about it, but he takes them all to
be oscula. For the rest he speaks about the peculiarity of the dermal membrane, remarking that it
consists of: “einer dusseren sarcodeartigen und einer inneren festen membranésen Schicht”. From
his description of the papille it is seen, that it is a pore-papilla he has examined, which are also
by far the most numerous; the fact is that he says: “Das Ende der Warzchen ist etwas verdickt,
der Gipfel scheinbar geschlossen, allein eine massige Vergrésserung zeigt, dass der Hauptcanal in
einer Anzahl Haarcanalchen sich nach aussen 6ffnet”. The “Haarcandlchen” Schmidt has seen are
no doubt the inner cavity divided by the fibres, and his description is otherwise in the main correct,
only he takes the papilla to be an oscular-papilla.

The skeleton. The dermal skeleton; the skeleton formed by the dermal spicules is not much
developed, it consists of larger or smaller bundles of dermal spicules lying in the membrane, partly
horizontally, partly more or less erect in the somewhat thick dermis; besides the bundles more
scattered and single spicules may also occur, but they are on the whole scarce, and large parts of the
membrane may be seen without dermal spicules. At the base of the papillae they are present in
greater numbers, and from here they stretch out in the wall of the papilla and form the skeleton of
the papilla as mentioned above. The mazu skeleton is a rather diffuse and irregular, multispicular
reticulation in which primary and secondary fibres cannot be discerned; also single spicules are in
many places seen to contribute to the skeleton. In the points of union is seen a distinct and rather
rich amount of spongin which may also sometimes be seen to continue along the fibres.

Spicula: a. Megasclera. 1. The skeletal spicules are styli, they have an even, generally
slight curve, lying nearest to the rounded end. The apex may be somewhat different, partly in the
saine individual, but especially in different individuals; it is generally of moderate length, but it may
be both shorter and longer, and it may be bounded by straight or curved lines; finally it may be
marked off in different ways; in a single specimen the point is often rounded and thus stubby. The
length of the styles may vary considerably, yet generally not much in the single individuals, but on
the other hand in different individuals; in all it is in the species between 0-30 and 068™", but only when
the sizes measured for all individuals are taken into consideration; as the common lengths may be
given 042—0'53™". The diameter is on the whole 0:007™™—o014™", but here also some difference is
present, in single specimens not reaching beyond o‘o11—o012™. 2. The dermal spicules are tylota,
they are generally straight, sometimes slightly curved. They have a distinct, but often rather elongated
swelling at each end as a rule passing evenly into the shaft; this latter is sometimes somewhat poly-
tylote. Also with regard to this spicule the length varies somewhat from individual to individual and
follows herein the variation of the styles; the length lies in all between o-25 and 047™", generally it

is 032—o'41™". The diameter is about 0:003—0:006™", but sometimes does not reach the latter size.

1*

4 PORIFERA. III.

The fully developed tylotes have about equal ends, but single developmental stages were seen, distinctly
showing, that the tylote originally is monactinal. b. AMicrosclera; there is only one form, rhaphides;
they have the special shape which is probably common to all the rhaphides in the species of Zedanza.
One end is short and curiously, obliquely pointed, while the other end tapers into a long, very fine
apex; otherwise they are spinulous which under a low magnification is only seen as an indistinct fine crenu-
lation; under a greater magnifying power it is on the contrary seen, that they are distinctly spined, the spines
being dentiform and strongly compressed in the longitudinal direction; the smaller rhaphides are the
relatively most strongly spined (Pl. IV fig.1c). The length varies to a very high degree in the
single individual, and also somewhat from individual to individual; it is in all o053—o'50™™, gen-
erally it is oo60—0'32™". Whether these different sizes are developmental stages it is difficult to de-
cide, but it is most probable, that they are, at all events for a great part, fully developed forms. To
be sure all intermediate sizes are seen between the given sizes, but certain sizes seem to predominate
and I am inclined to think, that three different, independent sizes are present (Pl. IV fig. 1c). When
intermediate sizes are found between them, this may be due partly to the variation of the single
sizes, but perhaps also partly to the fact, that a number of developmental stages are present among
them. The thickness is, in relation to the length, about ooo10—o'0028™"; the latter thickness was
only reached by the longest rhaphides and consequently not found in all individuals. The rhaphides
occur in great multitude both in the dermis, and otherwise in the tissue of the sponge; they occur
both in dragmata and singly and scattered; I have however only seen the large rhaphides in drag-
mata; all rhaphides in a bundle seem to have the equal ends turned in the same direction.

To show the variation in the length of the different spicules in various individuals and how
the lengths with regard to all three forms of spicules are in the main related to each other I may

give some measurements:

Styles tylotes rhapides
0'30—0'35™ o'25—0'32™™ o'055—0'25™™" (small specimen).
0°35—0'47™™ 0'27—0'33 mm 0'°053—0'29™™
044—0'49™™ o'3I—0'38™ 0'°064—0'320™™
0'43—0'53™™ o35—041™™. 0°064—0'329™™
0'51—068™™ 0'35—0'47™™ 0:064—o'50™™

Remarks: As Schmidt's type-specimen is found in my material, the identification is certain. I
have also examined a type-specimen of Z7edania increscens O. Schmidt, and have thus been able to
decide with certainty, that this species is identical with swctoria. Thiele thinks l.c. that zzcrescens
might be a good species, because its styles are larger than the measurements given by Schmidt for
suctoria; but the variations of the spicules given above show however, that from this no character can
be drawn. Topsent himself (Rey. Suisse de Zool. IV, 1897, 454) has abolished Zedania conuligera as
identical with sacforia, and his description also shows, that this is correct. The specific characters for
the species of Zedania seem especially to lie in the shape of the dermal tylotes, and this is not
astonishing, as the dermal spicules in other JZyxil/ee are also characteristic. Besides 7: suctoria I
have examined 7. digitata O. Schmidt, tenuicapitata Ridl. and massa R. and D., and of these species I

have examined specimens of sucforia from the whole Ingolf territory and from the Willem Barents

PORIFERA. III. 5

Expedition, and of digitata from Trieste, Senegal and the Antilles, and I have in these species
found the dermal spicules characteristic and constant. 7. sucforia has tylota with generally weak
and elongated end-swellings, 7: digitata has tylota with more or less weak end-swellings bearing
some spines on the end, 7: ¢enaicapitata has tornota, and when Ridley and Dendy say (Chall. Rep.
Monaxonida, 52), that the dermal spicules in this species may also have round end-swellings, but in
a foot-note declare, that such spicules were only found in one specimen, in which also tornotes occur-
red, then no doubt a mistake or confusion must have taken place. Finally 7: massa has dermal spi-
cules which may best be termed strongyla but with a little mucro on the end, and the latter may be
quite slightly swollen.

The rhaphides in the species of Zedania have been somewhat differently understood; Schmidt
only mentions them as “feine umspitzige Nadeln”, but does not mention, that they are spinulous; this
fact is first stated by Ridley (Proc. Zool. Soc. 1881, 124) in the description of Z: tenuicapitata and in
the same place the author explains, that such is also the case im a couple of Bowerbank’s
species (aspera and rudis) and in suctoria O. Schmidt; the author speakes of it as “roughness”, and
says that it is distinct from “spination” or “microspination”. Later the fine spinulation of the rha-
phides is mentioned by several authors as Carter, Ridley and Dendy, Lambe, Topsent, Lind-
gren and Thiele. In the four species I have examined, the rhaphides are mainly of the same shape,
and they are always finely spinulous in all specimens; I take it therefore as very probable that the
Tedania-rhaphides are always spinulous, and I consider it as certain, that smooth and spinulous rhaphides
cannot occur in different individuals of the same species. Ridley describes originally the rhaphides
in 7. tenuicapitata as “roughened almost imperceptibly”, but in the Chall. Report it is declared, that
the authors in the specimens which they then had for examination had only found spinulation of the
rhaphides in one specimen and moreover only in a spiculum which was not fully developed; I have
however examined specimens of 7: ¢enuicapitata from the Challenger Expedition and found the rha-
phides spinulous; the spinulation is fine, but rather well distinguishable already by a magnifying
power of 300; when the authors have seen the spinulation in a small spiculum, this is easily under-
stood, as in the small rhaphides it is most distinct, and, as said above, it is also probable, that the
small rhaphides are not developmental stages, but fully developed spicules. With regard to the rha-
phides in 7: massa the authors say: “they often exhibit a roughening of the surface...”; my exami-
‘nation of the species showed, that the rhaphides are always spinulous. About the rhaphides in 7.
commixta, tnfundibuliformis and actiniiformis Ridley and Dendy do not mention whether they are
spinulous or not, but as spinulation is not mentioned, it has probably not been seen; it is yet un-
doubtedly present. Topsent records (Rev. Suisse de Zool. IV, 1897, 454) a 7: digitata and says, that
he refers it to this species, though it has spinulous rhaphides, which have not been described with regard
to 7. digitata; this however is not correct, as Carter already in 1886 (Ann. Mag. Nat. Hist. 5, XVII,
52) has declared, that the rhaphides in 7: digitata are spinulous. Topsent is therefore of the opinion,
that the rhaphides in 7: digitata, and on account of the declaration of Ridley and Dendy, also in
massa and tenuicapitata and moreover in suctoria, are able to vary, being either smooth or spinulous;
according to what has been said above it must be considered as certain, that they are always spinulous.
A statement of Lindgren (Zool. Jahrb. XI, 1898, 299) about the variation in the species of Zedania

6 PORIFERA.. III.

and which is based on the statement, that: “Topsent dargethan, dass die Raphides bei dieser Art sowohl
glatt als auch stachelig sein kénnen”, therefore loses its relevancy. Thiele describes in 1903 (Abhandl.
Senckenb. nat. Gesell. XXV, 945—947, Taf. XXVIII, Fig. 12—15) four new species of Zedania; about
one of these is stated, that it has distinctly spinulous rhaphides, with regard to two others is said
respectively “ziemlich glatt” and “kaum rauh”; only about the fourth it is said, that the rhaphides are
smooth; I think that a sufficient magnifying power would show, that they all have spinulous rhaphides. In
1905 the same author further describes (Zool. Jahrb. VI, 430—33, Taf. 30, Fig. 50—53) four new species;
these are declared to have spinulous rhaphides, only with regard to one this is not mentioned. With
regard to the forms mentioned by Baer (Arch. fiir Naturgesch. 72, I, 1906, 17—19) as J: digitata vatrr.
sanstbarensis, fragilis and conica the rhaphides are only spoken of in a few words, and it is not said,
that they are spinulous. Topsent describes (Bull. du Mus. @hist. nat. 1907, 69, and Exp. Antarct. Fr.
1903—05, 30, Pl. V, fig. 6) a new species 7; Charcoti and mentions, that the rhaphides are spinulous;
they are present in two forms, of which one is shorter than the other and has a swelling near one
end, a shape already noticed by Thiele for one of his species. — Finally I may note that the two
species described by Kirkpatrick (Nat. Antarct. Exp. Nat. Hist. IV, 1908, 32—33) vardolosa and Cowl-
mani, and by the author referred to Zedania, are without rhaphides.

Still it must be noted, that Ridley and Dendy in the description of 7: actiniiformis advance
as probable the theory, that the rhaphides in this and in other species of Zedania are develop-
mental stages of the dermal spicules; the special shape and the whole structure of the rhaphides,
however, show with full certainty, that such cannot at all be the case, and besides the real develop- .
mental stages of the dermal spicules are not difficult to find.

Locality: Of this species we have a very large material from the whole Ingolf territory;
station 27, 64° 54’ Lat. N., 55° 10’ Long. W., depth 393 fathoms; station 34, 65° 17’ Lat. N., 54° 17’ Long. W.,
depth 55 fathoms; station 46, 61° 32' Lat. N., 11° 36’ Long. W., depth 720 fathoms; station 52, 63° 57’
Lat. N., 13° 32' Long. W., depth 420 fathoms; station 54, 63° 08’ Lat. N., 15° 40’ Long. W., depth 691 fathoms;
station 78, 60° 37’ Lat. N., 27° 52’ Long. W., depth 799 fathoms; station 87, 65° 02’ Lat. N., 23° 56’ Long. W.,
depth 110 fathoms; station 89, 64° 45’ Lat. N., 27° 20’ Long. W., depth 310 fathoms; station 94, 64° 56'
Lat. N., 36° 19’ Long. W., depth 204 fathoms; station 97, 65° 28’ Lat. N., 27° 39' Long. W., depth 450 fathoms;
station 127, 66° 33' Lat. N., 20°05’ Long. W., depth 44 fathoms; further it has been taken in the Davis
Strait, depth 1oo fathoms (Th. Holm), at East Greenland, depth 100 fathoms (Ryder), Axarfjord on
Iceland, depth 20 fathoms, (“Beskytteren” Otterstrom), at the East coast of Iceland, depth 38 fathoms
(Horring), Borgarfjord on Iceland, depth 85 fathoms, (Hallas, the type-specimen of Schmidt), on 64° 56’
Lat. N., 11° 48’ Long. W., depth 115 fathoms, East of the Farée Islands, depth 220 fathoms, (Ad. Jensen,
the cruise of “M. Sars” 1902), 64° 58' Lat. N., 12° 4o' Long. W., depth 70 fathoms, (the fishery investigation
steamer “Thor”); South-east of Nolso, depth about 70 fathoms, (Th. Mortensen), between the Faréde
Islands and Shetland Islands, depth 255 fathoms (Wandel); in all about 25 larger and smaller speci-
mens. The localities are situated in the Davis Strait, the Denmark Strait, North, East and South of
Iceland, between Iceland and the Farde Islands, at the latter and between these and the Shetland Islands.

Geogr. distr. The species has earlier been taken South-west of Bukenfjord, Norway, depth
106 fathoms (Schmidt), the Barents Sea, depths 112, 128 and 180 fathoms (“Willem Barent”), off New-

PORIFERA. III. 7

foundland, 46° 50’ Lat. N., 50° 12’ Long. W., depth 82 fathoms and at the Azores in depths of 318 and
664 fathoms (Topsent). The species is thus distributed between 74° 36’ and 38° 35’ Lat. N. and between
36° Long. E. and 56° Long. W. The bathymetrical range varies somewhat greatly, from 20 fathoms
(Axarfjord, Iceland) to 799 fathoms (station 78, on the eastern slope of the Reykjanes Ridge).

Histoderma Cart.

Sponges of more or less bladder-like consistence ; the shape globular or roundish in the free,
not attached forms, more flattened in the attached forms. The body provided with somewhat long tubular
fistule, or with shorter or longer papille. An outer, solid dermal layer present, furnished with a skel-
eton of close-lying spicules. The skeleton of the inner body formed of partly regularly arranged, thin
fibres, not forming a reticulation, or of more scattered spicules. Spongin not present. Spicula: mega-
sclera only of one form, the same in the dermal layer and the inner body, they are diactinal, tylota, stron-
gyla or tornota, sometimes the ends are unequal, the spicules then being tylostrongyla or tylotornata;
microsclera; the characteristic microsclera are chele arcuate; to these sigmata are generally added,
and further trichodragmata may occur; the sigmata may be of one or two sizes, and a peculiar small

chela may occur (navicelligerum).

1. H. appendiculatum Cart.
Pl. I Figs. 6—11, Pl. IV, Fig. 2.

1874. Histoderma appendiculatum Carter, Ann. Mag. Nat. Hist. 4. XIV, 220, Pl. XIV, figs. 23—25, Pl. XV,
figs. 39 a—b.

_ Globular or more irregularly tuberous, provided with more or less numerous, tubular fistule ;
Jree, not attached. Surface smooth. The body surrounded by a solid, bladder-like dermal layer. Oscula in
the apex of some of the fistule, pores in the apex of others. The dermal skeleton formed of close-lying,
tangential spicules in several layers; the skeleton of the inner body consisting of thin fibres, running
irregularly, being regular only at the surface and parallel with this; there are no transverse fibres.
Spicula: megasclera tylota passing by intermediate stages into unequal-ended strongyla, 0:27—0°95”™;

microsclera two forms, chele arcuate o:0go—o'046"™", sigmata 0047—0'093”™".

Of this curious and interesting species — the type on which Carter founded the genus —
the Ingolf-Expedition has taken a somewhat rich material. The shape is in the whole as described
by Carter; the sponge consists of a globular or tuberous body, from which some few shorter or
longer tubular fistule issue. The body may be nearly quite globular, which especially seems to be
the case with the smaller individuals, but generally it is of a more or less irregular shape, often some-
what flattened. The fistulz are, in the specimens to hand, in most cases broken off, only some single
ones are whole; they are cylindrical and straight or more or less curved, the sponge thus strongly reminds
one of a potato with stolons; it grows freely, without attachment. The body has in the largest speci-
men a diameter of 20™™ and in the smallest of 8™™; the length of the undamaged fistulz is about

25™", they are of the same length in the small as in the large specimens, while on the other hand the

8 PORIEERA, Il.

thickness is somewhat different, from 2 to 4™" in proportion to the size of the specimen. The colour is
(in spirit) yellowish white. The consistency is hard and firm, the dermal rind forming a very firm
layer, the inner body on the contrary is soft; in most specimens the inner body has therefore con-
tracted strongly under the influence of the alcohol and lies like a clump in one side of the firm capsule
formed of the dermal layer. By exsiccation the tissue of the inner body contracts strongly, becomes
hard and of a yellow colour, so that it resembles wax, just as is mentioned with regard to the
tissue of the inner body in Oceanapia robusta (The Ingolf-Expedition VI, 1, Porifera, part I, 79). The
surface is smooth, only showing such a slight roughness as may be caused by the spicules imbedded
in the dermal layer and parallel to the surface. The sponge has outermost a very solid dermal layer
of a thickness of about 0'25™™; in places it may become thicker, up to 1™™; it surrounds the inner
body like a mail and is very easily loosened from it, and contains close-lying spicules in several
layers. Pores and oscula: Carter says: “Pores and vents not distinctly seen, but probably situated at
the extremities of the tubuli respectively”. This is also the case, but I too cannot solve the question
with full certainty, because most of the tubular appendages are broken off. The oscula are certainly
situated at the end of some of the fistula; these latter are tubular, hollow and somewhat thin-walled;
a couple of them give the impression of being undamaged, and these terminate with a simple opening
which in consequence should be the osculum; a couple of the fistule terminate with a formation
quite as described by Carter, it is with a conical spout, placed at the end of the fistula; whether this
is possibly the normal, closed osculum I do not venture to decide. Of poriferous fistulz there is in the
material only one present, a loose tube which is broken off and has a length of 20™™; this tube shows,
that the fistulae become more thin-walled outwards, and that the skeleton in the wall becomes more
scattered. The end of the fistula is rounded and forms a slightly swollen knob of a length of about
2°5™™; in this knob the skeleton of the wall is transformed and passes into the formation of a reti-
culation, in the meshes of which the pores are situated (Pl. I, fig. 11); the pores are oval or circular,
of a diameter of 0047—o17™". In the dermal layer on the other parts of the body no pores are
found. — As mentioned the inner body is inclined to get strongly contracted in alcohol and become
hard and brittle, and there is then a large hollow space inside the dermal layer. But in single cases
the inner body has on the contrary preserved its original shape and consistency; it then quite fills
out the cavity formed by the dermal layer. When a section is made of such a well preserved speci-
men, the canal system is shown; some large canals are seen terminating in some of the tubes, and
thus shown to be excurrent canals (Pl. I, fig. 8); besides, a multitude of smaller canals are seen. The
inner body lies quite loose in the cavity within the dermal rind, and it seems only to be attached at
the points where the fistulz issue; thus there are extended spaces below the dermal layer. The lumen
of the fistule is not directly continued into the canals of the inner body, as there is a diaphragm
present at the origin of the fistulae; this diaphragm has in some cases a circular opening in the
centre, but it seemed in other cases to be quite closed. When the dermal rind is removed, the surface
of the inner body is shown; this surface is then quite undamaged, and it has the netted appearance
which is so often seen on the surface of species of Reniera (P1. I, fig. 9); on examining a specimen
which wanted the dermal layer, one might, therefore, think that it must be an entire and un-

damaged sponge. The netted appearance of the surface is due to the same cause as in the species of

PORIFERA. II. 9

Reniera, being caused by the close-lying, circular openings of the incurrent canals which shine through
the thin, transparent outer layer, in which there are fine pores leading to the canals. The poriferous
fistule probably do not lead into canals, but are in connection with the space below the dermal
layer; perhaps it is these fistulae whose diaphragm shows no opening in the centre. The course of
the water-current will then probably be: it passes in through the poriferous fistule into the space
below the dermal layer, from here through the pore-shaped openings on the surface of the inner body
and into the canal system, then in due course passing into the larger canals and finally out through
the oscular fistulee.

The skeleton. The dermal skeleton; the outer rind is highly provided with spicules lying
very closely and in several layers, parallel to the surface; the spicules are not scattered, but arranged
somewhat circularly round the bases of the fistulae, as is already distinctly visible with a lens; on
the inner side of the rind there are some spicules which lie singly and rectangularly to the direction
of the other spicules, and thus more or less radiating in relation to the circlets. In the fistule the
ring-like arrangement of the spicules is retained, which is the cause why the fistule are very easily
broken; some fine fibres, consisting of few spicules, run lengthwise out through the fistulz, lying on
the inside of the wall, and continue from the base to the end of the fistule in longitudinal direction;
these fibres do not belong to the dermal skeleton, in so far as they are not found in the dermal
layer of the body, on the contrary they issue from the inner body, and they are probably of
importance in attaching it, and thus it is that the inner body, as said above, is attached only at the
bases of the fistule. In the ends of the fistule the dermal skeleton gets more scattered, and in the
oscular fistulze the spicules are here irregularly scattered, crossing each other, while in the poriferous
fistulee the skeleton outwards first becomes somewhat scattered, but outermost forms a reticulation.
The main skeleton or the skeleton of the inner body: In the inner body some fine fibres are found,
but they have no regular course and form no reticulation; they seem mainly to run in directions
parallel to the surface. At the very surface of the inner body such fibres are found numerously,
running just below the surface and parallel with this, and they show a definite arrangement. They
run together at the bases of the fistule and continue, as said before, out in the fistule; as they
radiate from the base of the fistule out in the surface, they become in the larger part of this
parallel with each other, but at places where the systems belonging to different fistula meet, the
fibres run in different directions. Transverse fibres are not found, and thus there is no reticulation
formed. The fibres are somewhat loose, they have an average thickness of o'105™™, and the distance
between them is generally or5- 0'25™". — It was said above, that the inner body lies loose in the
cavity of the dermal layer; as the fibres mentioned continue from the fistule inwards and form
a carpentry along the surface of the inner body, this latter is in reality kept in its place by this
carpentry, otherwise lying freely in the cavity and only attached at the bases of the fistule. — Spongin
was not observed, neither in the inner skeleton nor in the dermal skeleton. — Carter has not seen
the construction of the skeleton of the inner body; in his material the inner body has probably been
destroyed. Both in the dermal layer and in the inner body many foreign particles are imbedded,
especially Globigerinae.

Spicula: a. Megasclera; these are only of one form, tylotes, but with some single intermediates
The Ingolf-Expedition. VI. 3. 2

Io PORIFERA. III.

to strongyles. They are more or less curved, but rather slightly; the. shaft is thickest at the middle
and tapers somewhat towards the ends. The spicules vary very much in size, and at the same time
somewhat in shape; the smaller and thinner they are, the more distinct are the end-swellings;
these smaller spicules have equal or nearly equal ends; the larger and thicker the spicules are, the
smaller are relatively the end-swellings, so that in the largest of the spicules they may be only
slightly pronounced; in the largest spicules the ends are most often not equal, one has a somewhat
roundish swelling the other an elongated swelling tapering slightly ,outwards; not rarely the
swellings quite disappear, and then we get a strongyle with unequal ends, one rounded the other
more tapering, nearly truncately pointed. The various sizes must be taken to be fully developed —
spicules, since fine developmental stages in various lengths are found; the developmental stages have
unequal ends, the shaft being a little thicker in one end but a little thinner in the other, and here
with a more marked swelling. Quite single very fine developmental stages were found, which had one
end quite pointed. The length of the spicules is in all 027-095", with a diameter of oo005—o'021™".
The length of the spicules is different in the different parts of the sponge; in the dermal layer the
largest are found, while the smaller and smallest are found in the inner body, the separation is how-
ever not quite sharp. In the inner body they generally do not exceed o60™™, and about at the same
size also lies the lower limit for the spicules of the dermal layer. In the skeleton of the fistulze large
and small spicules are mingled. In the fibres running along the surface of the inner body the
spicules belong for the most part to the larger forms of the group with the smaller spicules, and
among them some of the largest spicules are found, and with this composition the fibres continue out
through the fistula. Carter mentions and figures two forms of megasclera; to this result he arrives
only by taking a pronounced tylote and a form without end-swellings, and in which one end is truncately
pointed; a form such as his figure 39a may be found, but not frequently, and there is, as said, only
one kind of megasclera. b. MJicrosclera; there are two forms, chele arcuate and sigmata. 1. The
chele arcuate have an evenly curved shaft, lobe-shaped ale and an elliptical tooth; their length
is o1o40—0'046™" and the diameter of the shaft is oo04™™, 2. The sigmata are of common shape
and more or less contorted; they are rather large, but they vary somewhat in size, the length is
0'047—0'093"" and the thickness 0:0028—o'0057™". The microsclera are present through the whole
sponge, they are scattered in the inner body and in the dermal layer strewn rather numerously
among the megascleres, and they are specially numerous on the inside of the fistulae; the sigmates
are everywhere more numerous than the chele.

Embryos. In one of the specimens which was cut through an embryo was found, lying in a
cavity in the inner body. It was globular and rather large, 3™™ in diameter. It was lying in the
cavity distinctly surrounded by a membrane. It was richly provided with spicules, both megasclera
and microsclera. The megasclera were fine tylotes of a greatest length of about o47™™, many of them
were very thin and had still one end pointed. They were scattered in the interior of the embryo,
but they were already close-lying at the surface and parallel to this, thus forming a layer with how-
ever no boundary inwards. The microsclera were developmental forms of chelz in various stages,
they were of somewhat different sizes, but reached a length of up to o057™", thus to a greater size

than in the fully developed sponge. Sigmates were not seen.

PORIFERA. III. 1I

We have a specimen of this species which I at first thought was a distinct form on account
of its smaller spicules, but which on closer examination proved to be a very young specimen of
appendiculatum. The specimen is globular, with a single fistula, and very small, about 3™™ in
diameter, and thus not larger than the examined embryo. It shows quite the same structure as the
full-grown specimens; it has a distinct dermal layer with subdermal cavities below, and also distinctly -
shows the skeletal structure of the inner body. The specimen is interesting in showing, that such small
specimens may have considerably smaller spicules than the grown specimens. It is yet no doubt only
the very small specimens which show in this respect any difference worth mentioning, and it is certainly
the case, that they very soon get spicules of the size normal to the species. The examined specimen
has probably just left the mother-sponge. The megacleres do not reach beyond o41™™, the chelz
are ooso™", and the sigmates are of the same sizes as in the full grown sponge. It is interesting to
notice, that the chele in this specimen are intermediate in size between the chelz in the embryo and
those in the grown sponge. The relatively long and fine megascleres in the embryo seem here to be
replaced by shorter but thicker spicules. :

Locality: Station 78, 60° 37' Lat. N., 27° 52' Long. W., depth 799 fathoms, about 29 more or less
damaged specimens; station 90, 64° 45’ Lat. N., 29° 06' Long. W., depth 568 fathoms, two specimens and
some loose fistula; further at 61° 15’ Lat. N., 9° 35’ Long. W., depth 478 fathoms, a very small specimen
(The fishery investigation steamer “Thor”), The localities are situated on the eastern slope of the
Reykjanes Ridge, in the Denmark Strait and West of the Fardée Islands.

Geogr. distr.: Carter had the species from the west coast of Ireland, depths 808 and 109 fathoms.
(Porcupine).

2. H. physa O. Schmidt.
Pl. I Figs. r2—13, Pl. IV, Fig. 3.

1875. Desmacidon physa O. Schmidt, Jahresber. der Comm. zur wissensch. Unters. deutsch. Meere in
Kiel fiir 1872—73, 118, Taf. I. Fig. 8—9.

1887. Cornulum ascidioides Fristedt, Vega Exp. wetensk. Jakttag. IV, 495, Pl. 25, figs. 1—2, pl. 29, fig. 21.

1903. Hlistoderma physa, Arnesen. Berg. Mus. Aarbog 1903, 16, Taf. I], Fig. 5, Taf. III, Fig. 9.

1903. _ — , Thiele, Arch. fiir Naturgesch. Jahrg. 1903, 385, Taf. XXI, Fig. 16a—b.

1909. _ — , Iwndbeck. Meddel. om Grénland, XXIX, 443.

Roundish or more irregular, sometimes somewhat erect, attached with a broad base; provided
with one or a couple of conical spouts. Surface smooth. The sponge surrounded by a solid. but not
thick, bladdery dermal layer. Oscula at the summit of the conical spouts, the pores on the side of these.
The dermal skeleton formed of close-lying spicules parallel to the surface. The skeleton of the inner
body consisting of fine fibres and bundles of spicules, running irregularly, but at the surface parallel
with this; without transverse fibres. Spicula: Megasclera strongyla with intermediates to subtylota,

a50—oa8oum,; microsclera of two forms, chele arcuate 0:035—0058"", trichodragmata o-11—o'12”™.

This species has a shape mainly as described by Schmidt. It consists (on account of con-
traction or destruction of the inner body) of a bladder, formed of the dermal layer. This bladder may

2*

I2 PORIFERA. II.

be more or less roundish or of a more irregular, sometimes somewhat erect shape. The largest
specimen in my material has a greatest extent of fully 30™™; it has two spout-shaped tubes and a
height of 18™™ from the base to the end of the tubes; the smallest specimen has an extent of about
5™™, My specimens are attached to stones with a broad base, one is growing on a crab. The con-
sistency of the outer layer is firm and hard; the inner body is brittle; in all specimens the latter is
contracted and forms only a clump at the base of the bladder, and the same can be seen to have
been the case with the specimen figured by Schmidt. The colour (in spirit) is whitish, The
surface is smooth. Outermost is found the dermal layer, it is constructed mainly in the same way
as in the preceding species, and has a thickness of about o15™". Pores and oscula: My specimens
are all in a rather bad condition, so that the examination of the arrangement of the pores and oscula,
which would seem to be rather interesting, may be somewhat deficient, and as the inner body is
destroyed, we get from this no information about the canal system. Only the largest specimen is in
such a condition, that it gives some information about pores and oscula, and I think, that the structures
shown by this specimen are typical for the species, especially as the figure given by Schmidt seems
to show a quite similar structure. This specimen has, as said, two tubular or conical spouts, formed
of the dermal layer; these spouts have a shape as shown on PI. I figs. 12—13. The osculum is found
as a simple opening at the summit of the conical end part of the spout; the spicules of the dermal
layer lie parallel with each other here and with one end towards the oscular opening. On the side
of the tube is found a circular opening, surrounded by a low, projecting wall; the opening is covered
by the poriferous membrane. The skeleton of the dermal layer forms here a reticulation, as fibres go
inwards from the edge of the wall and support the membrane. The pores are numerously present
in the membrane, they are small, of an average diameter of 0706™™.

The skeleton. The dermal skeleton; as in the preceding species we find outermost a firm
dermal rind which, however, in the present species is somewhat thinner and less solid than in afpen-
diculatum. It is provided with close-lying spicules parallel to the surface, and the spicules lie in
several layers; they are mainly more or less parallel to each other, but there are also, especially
on both surfaces of the layer, spicules present, both in bundles and lying singly, which are scattered
and cross the other spicules in all directions. The maiz skeleton; on account of the condition of the
material I have only been able to examine the skeleton of the inner body somewhat incompletely, it
seems however to be constructed quite as in appendiculatum; in the interior there are fibres and
bundles, and at the surface there are parallel fibres without transverse fibres; the fibres were measured
to a thickness of o08™" with a distance between them of o'29™". Spongin is not present in the
skeleton.

Spicula, a. Megasclera; these are of one form, strongyles, sometimes approaching to subtylotes;
they are slightly curved, generally irregularly and most frequently doubly. They are fusiform, tapering
somewhat towards each end. The length when all examined specimens are considered is o'50—o'89™",
and the thickness o7008—o020™", but in the single individuals they do not vary so much, as examples
may be given o50—o0'74™" with thickness of oo08—o015"" and 062 —0'89™" with thickness of oo1o—
o020"", Fine developmental stages are seen singly, the finest are monactinal. b. A“icrosclera; these

are of two forms, chelze arcuate and trichodragmata, 1. The chele arcuate are of the common shape,

PORIFERA. III. B3

the shaft not much curved with the curvature mainly lying in the middle, the ale and tooth are
of the same length, the tooth narrowly elliptical with a long, narrow tuberculum: In all the length
is between 0:035 and o058™" with a diameter of the shaft of o10028—o'007™", but the chelz also vary
somewhat in different individuals, e. g. 0°035—0'043™™, 0°045—0'054™" and o”050—0058™, and the
diameter of the shaft may be oo028—o004™™ and o004—o'007™". 2. The trichodragmata; the
single rhaphides are exceedingly, nearly immeasurably fine, less than o10006™", the bundles have a length :
of o11—o12™" and a thickness of about o021—0035™", the single rhaphides were measured to a
length of about o10™. The rhaphides seem not to occur singly, but only in bundles. The chele
occur both in the dermal layer and in the inner body, here rather numerously, the trichodragmata
are mainly seen in the inner body at its surface.

The identification of this, otherwise rather characteristic species, is certain, as I have examined
a piece of one of Schmidt’s type-specimens. Also of the Cornulum ascidioides Fristedt I have examined
a type-specimen and thus been able to decide, that this is the present species; Fristedt has over-
looked the trichodragmates, and the length, o07™™, he gives for the chelz is erroneous, as in his
type-specimen I found the chelz to be of a length of o058™™.

Locality. Station 6, 63° 43’ Lat. N., 14° 34' Long. W., depth go fathoms; station 16, 65° 43’ Lat. N.,
26° 58’ Long. W., depth 250 fathoms; station 89, 64°45’ Lat.N., 27° 20' Long. W., depth 310 fathoms;
station 94, 64°56’ Lat. N., 39° 19’ Long. W., depth 204 fathoms; station 97, 65° 28’ Lat. N., 27° 39’ Long. W.,
depth 450 fathoms; further the species has been taken at 62° 26' Lat.N., 4° 49’ Long. W., depth 228
fathoms and 62° 53' Lat. N., 9° 06’ Long. W., depth 245 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902);
seven specimens or fragments in all. The localities are situated in the Denmark Strait and between
Icelands and the Fardée Islands.

Geogr. distr. The species has earlier been taken South-west of Bukenfjord, Norway, depth 106
fathoms (Schmidt), @stfjord at Bergen, depth 292 fathoms (Arnesen), and in Baffin Bay 68° 08’
Lat. N., 58° 47' Long. W., depth 169—183 fathoms (Fristedt). The southern limit of the species is thus
at 59° Lat. N.

Histodermella nov. gen.

Sponges which in appearance and structure are like Histoderma; the consistency more or less
bladder-like. The shape varies from round or roundish forms through longish to tube-shaped, often slightly
branched forms; the body provided with shorter or longer tube-shaped fistule, or with shorter papille.
The sponge surrounded by an outer, very solid dermal layer with close-lying spicules parallel to the
surface. The skeleton of the inner body consisting of scattered spicules or irregular fibres, sometimes
more regular at the surface, but not forming a reticulation. Spongin not present. Spicula: megasclera
of two forms, but these are intermingled so that the spicules are the same in the dermal layer and the
inner body; the megasclera are diactinal, of the two forms one ts smooth, the other spined; the smooth
megasclera are tylota or strongyla, sometimes with the ends finely spined, the spined megasclera are
acanthoxea or acanthostrongyla. Microsclera may vary somewhat in composition, the characteristic
microsclera are chele arcuate, to these are added sigmata, and further trichodragmata may occur and

besides (natalensis) curious spined bodies (transformed chele? or forcipes?). Microsclera may be quite absent.

14 PORIFERA. III.

1. H. Ingolfi n. sp.
Pl. II, Figs. 1—4, Pl. IV, Fig. 4.

Of somewhat various shape, more or less roundish with a number of tubiform fistule which may
be branched; or of more irregular shape, showing several swellings or finally quite without swellings ;
growing freely without attachment. Surface smooth. Outermost a solid, bladder-like dermal layer. Oscula
at the summit of some of the fistule, (pores at the summit of others?). The skeleton of the dermal
layer formed of close-lying spicules parallel with the surface; the inner skeleton consisting of fine,
irregularly running fibres, which are regularly arranged at the surface parallel with this, without trans-
verse fibres. Spicula: megasclera of two forms, tylota 029—0'65"", acanthoxea o17—0'21"™; microsclera

two forms, chele arcuate o-021—0'028", sigmata 0:056—o'061™™,

This species in its exterior shape somewhat recalls Histoderma appendiculatum, but it is
generally less regular. Most frequently it consists of a more or less roundish body with a varying
number of tube-shaped appendages. These appendages or fistula may vary much in length and
thickness, and there are often, besides the larger, also some short and thin fistule; these may
be branched in different ways, and they may be more or less curved; the appendages also may
form swellings, the sponge in this case consisting of more than one roundish swollen part connected
by the appendages. Finally there are specimens which have no pronounced swelling, or no swelling
at all, the sponge then consisting of a somewhat sinuous, slightly branched tube of somewhat different
thickness in different places. In the largest specimen the body has a diameter of fully 20™™, the
longest fistula has a length of 42™™ and its thickness is 4™™; then we have specimens in all sizes
down to quite small, the smallest one has a body with a diameter of 2°5™" and a fistula of a length
of 14™ and a thickness of 1'7™", The sponge grows freely without any attachment. The colour (in
spirit) is yellowish white. The consistency is somewhat bladder-like, the outer layer is hard and firm,
the inner body brittle, the latter is as usually highly contracted, so that it only occupies a small
part of the cavity within the dermal rind. The surface is mainly smooth, yet the ends of the tangential
spicules of the dermal layer may sometimes be a little projecting. The sponge is outermost sur-
rounded by a solid and hard dermal layer, formed of close-lying spicules, the layer has a thickness of
about o'2™". Oscula and pores: A part of the fistule are distinctly seen to be oscular fistule, they
terminate with a simple opening, or they are in most cases more or less closed and terminate in
a conically pointed part which is either quite closed or shows an opening at the summit. Pores I
have not observed, but they are certainly placed at the end of some of the fistulee; in my material
however the outer part of these is often broken off; at all events pores are not found otherwise on
the body. The inner body is in nearly all specimens strongly contracted or quite destroyed, yet in
some single specimens it may be seen to have had a surface as in Hiéstoderma appendiculatum, with
pores leading into canals; the direction of the water-current therefore is probably the same as in that species.

The skeleton. The dermal skeleton; the skeleton of the dermal layer is constructed as in A.
appendiculatum; it consists of close-lying tangential spicules in several layers, the spicules are more
or less circularly arranged around the bases of the fistula, and here likewise, especially on the

inside of the layer, we find spicules which lie at right angles to the others, these latter spicules

PORIFERA. III. 15

being for a great part spined oxea. The skeleton of the fistule is also here arranged ring-like, but
outwards it soon becomes more irregular and scattered; fibres running through the fistule in longi-
tudinal direction are not found here, or they are at all events only very little pronounced and soon
dissolved into spicules lying more scattered in the longitudinal direction. The skeleton of the inner
body is constructed quite as in 4. appendiculatum, there are fine, parallel fibres running along the
surface and without connecting transverse fibres, and they run together at the bases of the fistula,
some of them may continue out in the fistule; in the interior of the inner body similar fibres are
found, but they are scattered without observable order; besides there is found a number of single,
scattered spicules, which for a great part are spined oxea. Spongin could not be observed in the
skeleton.

_ Spicula: a. Megasclera; these are of two forms, tylota and acanthoxea. 1. The tylota are
straight or slightly curved, they have a well developed swelling at either end, the shaft is thickest in
the middle. The length varies much, from o29g—0°65™", with a diameter of the shaft relatively of
0'7007—o'017™". Some developmental stages are found down to quite fine, the thinnest of them are
monactinal, the older show one end rounded or slightly swollen, while the other end has a pointed
swelling which represents the original apex, and the shaft is thinnest at this end. There is no differ-
ence between the tylotes in the dermal. layer and those in the inner body, but the developmental
stages are found in the interior. 2. The spined oxea or acanthoxea are curious and characteristic
spicules; they are straight or quite slightly curved, and relatively short and thick, the points are
middle-long and sharp; the spicule is coarsely spined in the whole length, only the points are smooth
to a greater or smaller extent. The length varies from o17—o21™ and the diameter from o-008—
oo14. Some single developmental stages were seen, the thinnest of them slightly spined, these
had a thickness of oo04™™. The tylotes form the dermal layer and the fibres in the inner body
are also found scattered singly in the interior; the spined oxea are seen scattered singly in the dermal
layer, but are for the rest present, as said, on the inner side of the layer, lying at right angles
to the other spicules, further they are found scattered in the inner body. b. Microsclera,; these
are of two forms, chelz arcuate and sigmata. 1. The chele are somewhat small, they have a
slightly curved shaft, the ale are incised below and drawn out in a point, the tooth is narrow. The
length is o021—o028™", and the thickness of the shaft about o1002™™. Chelz of somewhat deformed
shape were not infrequent. 2. The sigmata are rather fine, they are contorted generally about a
quarter of a turn; the length is oo56—o061"" and the thickness o'002—0:0028™". The microscleres
occur on the inside of the dermal layer and in the inner body, but they are on the whole not numerous.

“Cellules spheruleuses’’. In this species the so-called cellules spheruleuses occur, often in
enormous numbers; they occur especially on the inside of the dermal layer and the fistulae and in the
inner body, chiefly at the surface of the latter. They are roundish or more elongate and filled with
relatively large, refracting granules; their size is generally oo11—oo017™". Sometimes they are some-
what confluent to larger heaps of granules.

Locality: 'The species has only been taken on station 78, 60° 37’ Lat. N., 27° 52' Long. W., depth

799 fathoms, on the eastern slope of the Reykjanes Ridge; a somewhat large number of specimens.

16 PORIFERA. III.

2. H. coriacea n. sp.
Pl. II, Figs. 5—6, Pl. IV, Fig. 5.

Elongate, somewhat fusiform, sometimes cylindrical or more trregular and somewhat branched;
provided with generally short, papilla-shaped fistule in greater or smaller number. Growing freely, with-
out attachment. Surface somewhat rough, but without projecting spicules. The sponge ts surrounded by
a very solid dermal layer. Oscula and pores each at the summit of their own papille. The dermal
skeleton formed of close-lying, tangential spicules. The skeleton of the inner body consisting of scattered
spicules. Spicula: megasclera of two forms, strongyla with spinulous ends 0-24—ro02”™, acanthostrongyla

o'12—0°238"™. No microsclera.

This species has an exterior which certainly resembles that of the preceding species but how-
ever is somewhat different, and it is larger and more robust. It consists of a body with fistule, but
the body is never globular but elongated, generally somewhat fusiform, thickest in the middle and
somewhat tapering towards the ends; it is otherwise generally more or less irregular. Sometimes it
is not fusiform, and the sponge is then nearly cylindrical; sometimes it is somewhat branched. The
fistulae are generally rather short, often nearly papilliform and they are for the rest very irregular
both in shape and arrangement, and they may also be branched. When they are somewhat larger
they appear as branches, so that the sponge then assumes the branched shape. Most of my specimens
are somewhat damaged, but to judge from not damaged specimens the species is not attached, but
grows freely, which is also by far the most probable. The largest specimen, which is not quite entire,
has a length of about 100o™™ and a greatest thickness of 17™™; the other specimens are somewhat
smaller, down to about 5o™ in length. The colour (in spirit) is in most specimens whitish grey or
dirty greyish violet, the inner body is darker than the dermal layer and is obscurely reddish violet;
some of the smallest specimens are nearly quite white, but also in these the inner body is somewhat
darker. Whether the colour is original or due to the influence of alcohol has not been observed.
The consistency is, on account of the very thick dermal rind, very firm, the inner body is also in its
present condition rather firm, but brittle; it is strongly contracted and lies generally up to one side of
the dermal layer. The surface cannot be termed smooth as the close-lying spicules cause it to be
rough both to the sight and to the touch, but it has no projecting spicules. The sponge is outermost
surrounded by a very solid and hard dermal layer, provided with close-lying spicules; this layer is
very thick, from o4—o08"™". Pores and oscula: Some of the fistule or papille are oscular papillz;
they are distinguished by their conical shape, pointed towards the end, with an oscular opening
at the summit. The papilliform ends of the sponge-body itself are oscular papille. From the
oscular opening a canal, which is surrounded by a film-like membrane, leads down into the body.
The other papillz, which bear no oscula, are pore-papille. These fistulae or papille are of a different
shape from the oscular papille, they have rounded ends which are as a rule a little swollen; they are
present in greater numbers than the oscular papillae. The pores are only present in the outermost,
rounded end-part of the papille. In the middle, through the interior tissue of the papilla, runs a canal
which in the outer end-part of the papilla is divided into branches; these branches go to the surface

and are the incurrent canals into which the pores lead; these latter are lying in an irregular reticulation

PORIFERA. III. 17

and they have a diameter of 01036—o10™. ‘The circulation of the water-current is then the same,
as was mentioned under 77. appendiculatum; there is also here a space below the dermal rind, and
in a section of the inner body parallel with the surface the small, round incurrent openings to the
canals are, under the microscope, seen lying very closely.

The skeleton. The dermal skeleton; the skeleton of the dermal layer is formed of close-lying,
tangential spicules, which lie in several layers and form a solid and protective rind. The greatest
part of the spicules lie parallel to each other in a direction which goes more or less distinctly
circularly round the sponge, thus the spicules lie at right angles to the longitudinal direction of
the body of the sponge; at the same time they are, in the environs of the fistule, arranged ring-like
around the bases of these. When the surface is undamaged, there is outermost a layer of more loose-
lying spicules which lie crossing each other in all directions; between the regularly arranged spicules
of the layer there are spicules placed at right angles to the others. A section through the layer
parallel to the ring-like arranged spicules will thus show entire spicules lying parallel to each other
on the inside, and cut, irregularly lying spicules on the outside. The spined strongyla occur especially
at the outer side. The skeleton in the fistule is ring-like arranged at the base, but outwards it
passes soon into an irregular skeleton with spicules intercrossing in all directions; in the oscular
fistulee the spicules are in the conical summit arranged parallel to the longitudinal direction and with one
end towards the oscular opening; in the pore-fistulz there is at the end an irregular reticulation, in
the meshes of which the pores lie. The skeleton of the inner body is difficult to get a clear idea of
on account of the brittleness and contracted condition of the tissue, and also on account of its very
dark colour. It is however not regular as in the preceding species, but seems only to consist of
scattered spicules; at the surface they are present in greatest numbers while they are much scattered
in the interior, and they are on the whole not numerous. Spongin is not present in the skeleton.

- Spicula: a. Megasclera; these are of two forms, smooth strongyla and acanthostrongyla. 1. The
smooth strongyla are straight, more rarely quite slightly curved, they are thickest in the middle
and taper slightly towards the rounded ends, which latter sometimes may be quite slightly swollen.
The ends are very finely spinulous on the rounded part; the spinulation may be very little apparent
but is generally rather distinct, it is most obvious on the smaller spicules. The length varies much,
from 0'24™ and up to ro2™™", and the thickness is ooo8—oo021™. In the dermal layer strongyla of
all sizes are found, the larger are present in greatest numbers, in the inner body on the contrary only
the smaller forms are found, up to a length of 0-47™", but at the surface of the inner body they are
somewhat larger up to o71™. 2. The acanthostrongyla or spined strongyla are relatively
short and thick; they are generally sligtly curved, coarsely spined strongyla, sometimes each end
terminates in a point, but as this is not, or only very slightly, larger than the other spines, it must
be taken as such and the spicule must be termed a strongyle. The length is about o12—0'238™", the
shortest forms occur most rarely, the thickness is oo11—oo17™". The acanthostrongyla occur both in
the dermal layer and the inner body scattered between the other spicules; in the dermal layer they
are especially present towards the outer side. J/icrosclera are not present.

Locality: This is the same as for the preceding species, viz. station 78, 60° 37’ Lat. N., 27° 52’
Long. W., depth 799 fathoms.

The Ingolf-Expedition. VI. 3. 3

18 PORIFERA. IIL

This species seems to be very like Phlocodictyon birotuliferum Cart. (Ann. Mag. Nat. Hist.
5, XVIII, 447), to judge from Carter’s figure and description. This resemblance however is probably
only an analogy, without consequence in regard to affinity of the species (see below under the remarks
about the species of the genera in question).

The two Histodermella species established here, /wgolf and cortacea, are certainly rather nearly
related to each other; the outer shape, the dermal rind and the arrangement of the canal system are
in agreement; the differences lie mainly in the construction of the skeleton of the inner body and the

shape of the spined megasclera as also in the absence of microsclera in one species.

Inflatella O. Schmidt.
(Joyeuxia Topsent.)

The shape roundish or the sponge more or less club-shaped, sometimes pedunculated. The con-
sistency bladder-like. The body provided with more or less numerous papille. An outer, solid dermal layer
present, with a skeleton of close-lying spicules; the skeleton in the inner body weak, consisting of thin
fibres, not forming any reticulation. Spongin not present. Spicula; Megasclera of one form, diactinal,

strongyla; microsclera not present,

1. I, pellicula O. Schmidt.
Pl. II, Figs. 7—9, Pl. IV, Fig. 6.
1875. /nflatella pellicula O. Schmidt, Jahresber. der Comm. zur wissensch. Unters. der deutsch. Meer. in
Kiel fiir 1872—73, 117, Taf. I, Fig. 5,
1885. Reniera inflata Armauer Hansen, The Norwegian North-Atlant. Exp. XIII, Spongiadee, 7, Pl. I, fig. 4.
1903. /nflatella pellicula, Thiele, Arch. fiir Naturgesch., 1903, 385, Taf. XXI, Fig. 17.
1904. Joyeuxia viridis Topsent, Résultats des camp. scient. du Prince de Monaco, Fase. XXV, 205, PI. III, fig. 12.

Club- or pear-shaped, pedunculated, with some few conical papille above. The surface smooth.
The sponge surrounded by a solid dermal layer. Oscula and pores at the summit of the papille. The
dermal skeleton formed of close-lying, tangential spicules; the inner skeleton consisting of bundles or

loose fibres. Spicula: Megasclera strongyla 042—0' 64”.

The outer shape of this species is somewhat well known from the descriptions cited. It is
elongate, pear-shaped and is attached below by a shorter or longer peduncle to a substratum. The
peduncle may with regard to the manner of fixation be somewhat various; either it is only fixed by
means of a little dilatation, or it emits stolons which may shoot out at various heights, and each of
which has its own attachment. This is already mentioned by Schmidt lc Of the figures cited
above that given by Schmidt shows stolons, while the others show a single peduncle; the figure by
Topsent, however, shows a small projection above on the peduncle, evidently a beginning stolon,
as is also mentioned by the author. Above, the peduncle passes into the pear-shaped body which
bears one to four slender, conical papillae above. The specimen described by Topsent shows an

osculum without papilla. Of the specimens in my material the largest is 19", the smallest 10™ high;

PORIFERA. III. 19

the specimens previously described are of similar sizes. The papille vary in length from 15 to 4™™.
The colour (in spirit) is in one specimen green, but otherwise whitish, presumably on account of de-
colouration. The consistency is bladdery, the dermal layer being firm and solid, while the inner body
is soft and strongly contracted. The szrface is smooth. The dermai layer is a rather thin, firm mem-
brane, provided with close-lying spicules. Pores and oscuda: The pores are certainly found at the
summit of certain papille, as in one of the papillae I found a very distinct, sieve-like pore-membrane
with close-lying, circular pores, but as my material is somewhat damaged and only shows few papille,
I can say nothing further, but there are no pores found otherwise on the surface. Some others of the
papillze are oscular papille with a simple opening at the summit. That the papillz are partly oscular,
partly pore-papillz is also confirmed by what is found in the following species /. vzrzdis.

The skeleton. The skeleton of the dermal layer consists of close-lying, tangential spicules, inter-
crossing each other in all directions; they lie rather closely, but not more closely however than that
the membrane may be seen everywhere between them. In the peduncle they lie quite closely and
here they are all arranged parallel to the longitudinal direction; the layer is also here considerably
thicker, and the spicules lie in several layers; the peduncle, however, is not compact, but the inner
cavity continues down through it. In the wall of the papillz the spicules likewise lie quite close to
each other and all parallel to the longitudinal direction with one end towards the opening of the pa-
pilla. The skeleton of the inner body 1 have only been able to examine somewhat incompletely, as
the specimens in my material for the most part want the inner body; it is however not at all
devoid of a skeleton; there are bundles and loose fibres present which seem mainly to have a course
along the surface, but whether there is otherwise any definite arrangement I have not been able to
see. Spongin is not present in the skeleton.

Spicula: a. Megasclera; these are of one form, strongyla; they are slightly, generally somewhat
irregularly curved; they are thickest in the middle and taper a little towards the ends; these latter
are sometimes, either one or both, slightly swollen; there is often a little difference between the ends,
one being slightly thinner than the other, but most frequently such a difference is not observable.
The length is o42—o064™", most frequently about intermediate between these sizes, the thickness is
o'o10—0'0128"". Fine developmental stages were found singly, they are monactinal, and they are especially
found in the inner body. Microsclera not present.

As I have examined the type-specimen of the Reniera inflata Arm. Hans. the identification of
this with the present species is certain. — While the /Joyeuxia viridis Tops. (1. c. 1904) must be the
present species, the two specimens which this author described in 1892 for the first time (I. c. Fasc. II,
94.) and on which he founded the genus /oyewxia and the species vrdis, are on the contrary probably
a distinct species and identical with the species described below.

Locality: The Ingolf-Expedition has taken three specimens of this species on the following
localities: station 32, 66° 35’ Lat. N., 56° 38’ Long. W., depth 318 fathoms; station 81, 61° 44’ Lat. N., 27° 00’
Long. W., depth 485 fathoms, and station 97, 65° 28' Lat. N., 27° 39’ Long. W., depth 450 fathoms. The
localities lie in the Davis and the Denmark Straits.

Geogr. distr. The species has earlier been taken South-west of Bukenfjord, Norway, depth 106

fathoms (Schmidt 1. c.) and at 38° 31’ Lat. N., 26° 50’ Long. W., depth 449 fathoms. The species is thus
3

20 PORIFERA. III.

distributed in the Atlantic Ocean together with the Denmark and Davis Straits between 66° 35’ and
38° 31’ Lat. N., and with a bathymetrical range from 106 to 485 fathoms. For the specimens from the

Norwegian North-Atlantic Exp. no particular locality is known.

2. I. viridis Tops.
Pl. II, Figs. r1—12, Pl. IV, Fig. 7.

1892. /oyeuxia viridis Topsent, Résultats des camp. scient. du Prince de Monaco, Fase. II, 94, Pl. I, fig. 8,
Pl. X, fig. 19. .

Erect, somewhat club-shaped, or of a lower and somewhat semiglobular shape; there are more or
less numerous papille in the upper part. Surface smooth. Outermost there ts a solid dermal layer.
Oscula and pores cach at the summit of thetr own papille. The dermal skeleton formed of close-lying
tangential spicules in several layers; the tnner skeleton consisting of bundles and thin fibres running

parallel with the surface, without transverse fibres. Spicula: Megasclera strongyla 0-66—r10”™",

This species differs from the preceding one externally in being considerably larger and
in having no peduncle. Of the specimens in my material only three are tolerably entire; of these
the two are erect and somewhat club-shaped, being a little narrowed below, the third is lower and
relatively broader. Above, the sponge has more or less numerous conical papille; below, it has been
attached, and it would seem as if it had grown on the bottom itself, the base of attachment being
beset with gravel and other small particles. The largest of the entire specimens has a height of
30™=", and a breadth of about 18™™, and at the base a breadth of fully 10™™; another specimen of a
similar shape is somewhat smaller; the lower and broader specimen has a height of about 20™™
with a breadth of about 15"™™. The colour is (in spirit) light brownish yellow or olive; the colour of
the inner body is deeper than that of the dermal layer. The consistency is bladdery, the outer
layer hard and firm, the inner body brittle and soft. The szz/ace is smooth. The dermal layer is
provided with tangential spicules in several layers, and it is somewhat thicker than in / Aellicula and
reaches a thickness of about o5™", in places even more. Oscuda and pores: the papille mentioned are
partly oscular and partly pore-papille. The oscular papilla are conical, of a height of 3™, but they
may contract themselves and are then quite low. When they are open the osculum is a simple opening
at the summit. In the wall of the papille the spicules are close-lying; they do not lie, however, in the
longitudinal direction but in two directions crossing each other almost rectangularly and both obliquely
to the longitudinal axis of the papilla; when the papilla is quite extended the two sets of spicules
are arranged in rather distinct, but close-lying bands, but when the papilla is contracted and the
osculum closed the spicules form a compact mass and when the papilla is then examined from the
end the ends of the close-lying spicules are seen. The pore-papille are of another construction and
easily distinguishable from the oscular papillee; they are larger, especially broader, and they are not
conical but cylindrical; they are generally placed on the sides of the upper part of the sponge, and
they are not directed straight outwards but somewhat upwards so that their opening points upwards,
they are at the same time somewhat adpressed in towards the sponge and hence elliptical in circum-

ference; they have a breadth of 6—10™™"; on account of the manner in which they are attached, their

PORIFERA. IIL. 43

anterior wall is higher than the posterior, which is towards the sponge, e. g. 6 and 3™ respectively.
The elliptical opening is covered by a somewhat immersed pore-membrane, with very close-lying pores,
so that the membrane is sieve-like; the pores have an average diameter of o017™™. The walls of the
papille are provided with spicules which do not lie in the longitudinal direction, as is also the case in the oscular
papillz; they are here distinctly arranged in two sets of bands crossing each other more or less rectangularly,
and placed more or less obliquely to the longitudinal axis of the papilla; this oblique direction shows
for the rest a definite arrangement; while the bands on the hinder side of the papilla form an angle
of 45° to the longitudinal axis, those on the anterior side are more erect and most so on the middle
of the anterior side; the bands form by their arrangement a close reticulation with square or subqua-
drangular meshes. In the pore-membrane no spicules are found. The oscula are present in greatest
number e. g. up to seven, of pore-papille on the contrary only one or two are found.‘) The surface
of the inner body shows under the microscope an appearance almost as in //istoderma appendiculatum ;
through the surface shine the openings of close-standing incurrent canals; the course of the water-
current will thus be through the pore-sieves into the extended subdermal spaces, from here through
the fine pores in the surface of the inner body into the canal system, and then out through the oscula.

The skeleton. The skeleton of the dermal layer consists of tangential spicules in several layers;
the spicules are rather close-lying, but yet the tissue may everywhere be seen between them; they
intercross each other in all directions without any observable order, only a slight tendency towards
collecting into bundles is seen, with only few spicules in the bundles. The skeleton of the oscular and
pore-papillz is described above. The skeleton of the inner body. As in J/. pellicula a close examination
shows that the inner body also in the present species is provided with a skeleton; in the interior this
skeleton consists only of quite single scattered bundles, but on the other hand it forms distinct fibres
at the surface, running parallel with this, and it is thus in the main constructed as in the species
of Aistoderma. As far as I could observe no spongin is found in the skeleton.

Spicula: a. Megasclera are of one form, strongyla, they are more or less, generally somewhat
irregularly curved, more rarely straight; sometimes the curve is somewhat sharp; they are thickest in
the middle and taper somewhat towards the ends but most frequently only to a slight degree. The
length varies a deal, from o66—110™", they are rather slender, the thickness is in the middle oo11—
oo14™™. Fine developmental stages, which are monactinal, are found in the inner body.

Embryos. In a couple of specimens embryos were found; they were lying in the inner body
close to the dermal layer; they are globular, of a diameter of about o48™™; the examined embryos
showed no spicules.

Whether this species is really identical with Topsent’s wridis it is difficult to decide, but as
the only difference is, that the spicules in Topsent’s species are somewhat smaller, 0°76", there is

good reason to take them as identical. When Topsent declares, that the inner body is quite

1) Since this was written the work of Kirkpatrick (Nat. Antarct. Exp. Nat. Hist. IV, 1908) has appeared; here
the author describes a very interesting species I. Belli (Joyeuxia) (41, Pl. XVI, figs. 1—5 a); this beautiful /fatella has on the
surface numerous papillz, easily seen to be oscular and pore-papillee; the pore-papille are about 1°™ long, trumpet-shaped,
with a pore-sieve over the wide opening; the oscular papille are simple and smaller, about 4™™ long. In this species the
facts with regard to oscula and pores are thus principally the same as described above, but both kinds of papillae are much
more developed.

22 PORIFERA. III.

without spicules, these have surely only been overlooked. Topsent’s specimen had lost the upper
part, and oscula and pores therefore were unknown to him, and consequently it is incorrect, when he
says, that pores pierce the dermal layer singly. |

Locality: Station 92, 64° 44' Lat. N., 32° 52' Long. W., depth 976 fathoms; about five more or less
damaged specimens.

Geogr. distr. The species has been taken 25° right south of the Ingolf locality between 38°
and 39° Lat. N., at the Azores in depths of 241 and 391 fathoms (Topsent 1. c.).

Remarks. Topsent says (l.c. 1904, 207) that still another species*belongs to /wflatella (= Joyeuxia),
viz. ascidioides Fristedt; this species, however, is identical with A/zstoderma physa, as mentioned above
under this species. When Topsent says in his generic diagnosis, that chele may occur in the genus,
this is therefore erroneous.

Inflatella sp. Vosmer (1885. Bijdr. tot. de Dierk. ra‘e Afl. 3* Gedeelt. 21, Pl. I, fig. 8, Pl. V, figs.

17—I9) is a Vosmaerta.

Cornulum Cart.

The shape somewhat various, the sponges being erect and obconical or more roundish or semt-
globular with a broad base. The consistency somewhat bladder-like. With or without Jistule. Outermost
a solid dermal layer with close-lying spicules. The skeleton somewhat solid, consisting of rather thick
fibres, dendritical or reticulated. Spongin present. Spicula: Megasclera diactinal, oxea or strongyla,
the latter sometimes with the ends finely spinulous; the megasclera are either of one form and equal
through the whole sponge, or of two forms, oxea in the skeleton and strongyla in the dermal layer;
microsclera: the characteristic microsclera are tsochele palmate either solely, or (textile) together
with toxa.

1. C. textile Cart.
Pl. II Figs. 13—14, Pl. V, Fig. 1.

1876. Cornulum textile Carter, Ann. Mag. Nat. Hist. 4, XVIII, 309, Pl. XII, fig. 9, Pl. XV, figs. 28 a—b.
1887. -- — , Fristedt, Vega Exp. vetensk. Jakttag. IV, 446.
1909. — — , Lundbeck, Meddel. om Gronland, XXIX, 443.

Erect, obconical, with a flat uppér surface. Outermost a thin but solid dermal layer. Surface
smooth. Oscula lying to one side in the upper, flat plane, pores occupying the rest of the plane. The
dermal skeleton formed of rather close-lying spicules in one layer. The inner skeleton strongly developed,
regularly dendritical, consisting of fibres which go upwards fromthe base and bend out to the surface,
they are connected by transverse fibres. Spicula: Megasclera one form, strongyla with finely spinulous
ends, 0-32—0'536"",; microsclera of two forms, chele palmate o-o1g—o017””", toxa, long and fine,
o°2I—0°30™™.

This curious and interesting species has on the whole a shape as described by Carter lc. It
is erect and has been attached with its lower, quite slightly dilated or swollen base to some object

on the bottom; all the specimens in my material are, however, torn off, but the flat attachment is

distinct. Carter also says: “attached to hard objects”. From the base it rises upwards with a stalk-

PORIFERA. III. 23

shaped part, but it gradually increases evenly in thickness and reaches its greatest diameter at
the upper end. To judge from a couple of specimens which have the upper end tolerably undamaged,
the sponge is here suddenly and slightly obliquely cut, with a plane upper surface, which perhaps has
had an oscular tube; it is thus of a slender obconical shape, and is generally quite slightly curved, so
that it may very well be compared with a horn, as Carter says; further the sponge has some more
or less distinct, ring-like contractions. The size is about the same in all the specimens in my material,
the length 30—40™, the thickness above 6—10™". Carter’s specimen had a similar size. The con-
sistency is bladdery but, on account of the firmness of the outer layer, somewhat solid. The colour
(in spirit) is yellowish white. The surface is smooth. The dermal membrane is a thin, but firm and
solid membrane, provided with close-lying spicules arranged in one layer. Oscuda and fores: Carter
supposed that oscula and pores were placed in the upper end of the sponge, but his specimens were
damaged here; my specimens also are more or less damaged in the upper end, yet a couple are so
much undamaged, that they give some information with regard to the place and structure of the
oscula and pores. The upper surface of the sponge is, as said, somewhat obliquely cut and is thus in
the main plane; on this lie an osculum and the pores. The osculum is a nearly circular opening with
a slightly projecting edge, it has a diameter of 1°5™"; it is in both the examined specimens placed
close to the margin of the upper surface. and a wide canal leads from it down towards the base of the
sponge. In the other part of the upper surface lie the pores, they are circular or oval and so close-
lying that a sieve is formed; the incurrent openings to a number of canals are seen shining through
the pore-membrane; the pores are of a size of 0':023—0'12™".

The skeleton: The dermal skeleton. The outer membrane is provided with spicules lying close
to each other in one layer, but they-are not closer than that the membrane may be seen everywhere
between them; the spicules are parallel with the surface and mainly arranged in the longitudinal
direction of the sponge; on the inside of the membrane some spicules are found which are arranged
at right angles to the others and thus lying transversely, they lie singly or a few together. The
membrane thus furnished is a little projecting above in the circumference of the sponge, and here
the spicules also project; the pore-membrane, which covers the upper surface of the sponge, is pro-
vided with a skeletal reticulation, forming the meshes in which the pores lie; this reticulation
is for a great part unispicular and irregular. In the part of the membrane surrounding the oscular
aperture, there are some short fibres, directed towards the aperture. The mazn skeleton is of a regular,
dendritical construction; from the base fibres go upwards through the sponge; in the centre they are
most powerful, and from here fibres steadily bend outwards which, running obliquely upwards, go to
the surface; these fibres have a somewhat regular course and are parallel with each other, and they
are connected by transverse fibres, which, however, are placed more irregularly; the fibres are strong
and consist of many spicules; they have an average thickness of o'12™", those in the middle being still
thicker; the transverse fibres are thinner. The distance between the longitudinal fibres is about o-5™.
Above, the fibres spread themselves out and support the membrane of the upper surface, and the spicules
are here a little projecting. As will be seen the skeletal reticulation thus formed is rather regular,
and the skeleton is intermediate between a dendritical and a reticulate skeleton. In the skeleton a

distinct amount of spongin is found, which in most places may be seen to coat the fibres with a

24 PORIFERA. III.

layer; spongin is also present in the dermal membrane, and on examination the membrane gives the
impression of being quite or partly a spongin-lamella; the spongin of the skeletal fibres continues
directly over into the membrane. It is this consistency of the membrane about which Carter uses
the expression “a horny sarcodic membrane”. In the membrane there are found fine thickenings or
slightly elevated lists running circularly round the sponge, they seem to be thickenings of the spongin,
and are possibly phenomena of growth.

Spicula: a. Megasclera are somewhat curved strongyla, they are thickest in the middle and
taper towards the ends, more towards one end than towards the other, and they are thus unequal-ended.
The ends are quite slightly spinulous outermost on the rounded part, sometimes they may be smooth.
The length is 0-32—0'536™" and the thickness is oor7—o022™. Some finer to quite fine develop-
mental stages were seen, the finest are monactinal and thus show that these unequally-ended strongyles
originate from styles. b. Mcrosclera; these are of two forms, isochele palmatee and toxe. 1. The
chele palmate are very small and of the typical shape, the tooth is of the same length as the
alee and of the same breadth as these together; the ale seem to be only very slightly refolded
laterally so far as I could see under a high magnifying power (x 1400). The length is oo14—o017™
and the breadth about o0028™. 2. The toxa are long and fine, the curvature is most frequently
very slight; sometimes they are only curved in the middle, but most frequently also the end parts
are slightly recurved; sometimes they may be somewhat irregular, so that their shape as toxa is not
distinct; they are of the same thickness in the whole length, only the ends are finely pointed. The
length is o'21I—o-30™ and the thickness about ooo16™. Carter mentions and figures as “subskeleton
spicules” some fine spicules, which he terms “acuate”, but his figure shows two, of which one is a style,
the other pointed at both ends; it is presumably a confusion of developmental stages of the strongyles
and toxa which forms his “subskeleton spicules”. I have not seen toxa quite so strongly curved as
shown by Carter’s figure, but no doubt they may vary a good deal in curvature. The microsclera
occur everywhere in the soft tissue of the sponge, the chele are present in very great numbers.

Embryos. In one of the specimens an embryo was found; it was situated about in the middle
of the sponge and had a size of about 06™". It contained numerous megascleres, but there seemed
to be no microscleres present. The megascleres are similar to those in the grown sponge, only con-
siderably smaller, of a length of about 0:20™™.

Locality: Station 4, 64° 07' Lat. N., 11° 12' Long. W., depth 237 fathoms; station 143, 62° 58’ Lat. N.,
7° 09’ Long. W., depth 388 fathoms, (bottom temperature + 0° 4C.); further it has been taken at 62° 4o'
Lat. N., 1° 56’ Long. W., depth 365 fathoms (bottom temperature + 0° 3 C), 62° 29' Lat. N., 4° 12’ Long. W.,
depth 283 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902); finally it has been taken at East-Green-
land, 74°17' Lat.N., 15° 20’ Long. W., depth 127 fathoms (The East-Greenland Exp. 1891—92). Five
specimens or fragments in all.

Geogr. distr. The species was earlier taken on the “Porcupine” Expedition, 61° 10’ Lat. N., 2° 21'
Long. W., depth 345 fathoms (bottom temperature -- 1°1(C) (Carter 1. c.), and in the Baffin Bay, 72° 32’
Lat. N., 56° 05’ Long. W., depth 116 fathoms. The species is accordingly distributed between 1° 56’ and
56° os’ Long. W., and between 61° 10’ and 74°17' Lat.N., in the Baffin Bay, at East-Greenland and
around the Farde Islands. The depths are from 116—388 fathoms. The species presumably belongs

PORIFERA. III. 26

mainly to the cold area, as the localities, as soon as they are deeper than 300 fathoms, show a negative

temperature, but it may also go higher up and here occur in water with a positive temperature.

Remarks about the species of the genera Histoderma, Histodermella, Inflatella

and Cornulum:

Of species which belong here, or have been supposed to belong here, there are at present

described the following:

1874. Histoderma appendiculatum Cart. (cited above). .
1875. Desmacidon physa O. Schmidt (cited above)....
1875. /nflatella pellicula O. Schmidt (cited above)....
1876. Halichondria phlyctenodes Cart. (Ann. Mag. Nat.

Tylota to strongyla — chele arcuate — sigmata.
Strongyla — chele arcuatee — trichodragmata.

Strongyla.

Hist. 4, XVIII, 314, Pl. XIII, fig. 17, Pl. XV, fig.35) Tornota — chele arcuate — sigmata.

1876. Cornulum textile Cart. (cited above)...........

1883. Phloeodictyon singaporense Cart. (Ann. Mag. Nat.
Hist. 5, XII, 326, Pl. XIII, fig. 17a—b).......
1885. Szderoderma navicelligerum Ridley and Dendy,
(Challeng. Rep. XX, Monaxonida, 115, Pl. VIII,
Bea es tee ae GB el ea

1886. Histioderma verrucosum Cart. (Ann. Mag. Nat.
PER ON AR a as aw haw ima ss
1886. Histioderma polymasteides Cart. (Ann. Mag. Nat.
Pa Bi PERLE ASS oo 6 Cite penx 9 eee eres.
1886. Pseudohalichondria clavilobata Cart. (Ann. Mag.
aay Eo a8 0) ee
1887. Cornulum ascidioides Frstdt. (cited above) .....
1887. Cornulum enteromorphoides Frstat. (Vega Exp.
vetensk. Jakttag. 447, Pl. 25, figs. 3—6, Pl. 29,

1888. Sideroderma Zitteli Lendenf. (The Austral. Mus.
Descrip. Catal. of Sponges, 211).............
1892. Joyeuxta viridis Tops, (cited above)............
1903. Histoderma mnatalense Kirkpatrick, (Marine
Invertebr. in South Africa, III, 250, Pl. V,
me 27,1. Viv ape 1B a eyo i op ase.

1904. Joyeuxta tubulosa Tops. (Résultats des camp. sc.
du Prince de Monaco, Fasc. XXV, 206, Pl. V,
igs Sy Eh ee ON LG) s coersicns, iit ae oyu’

The Ingolf-Expedition. VI. 3.

Strongyla with spinulous ends — chele pal-

matze — toxa.

Oxea — short strongyla — chele palmate.

Tylota — small peculiar chele — sigmata of

two sizes — trichodragmata.

Tylostrongyla — chele arcuate — sigmata.
Tylota to tylotornota — chele arcuate?
Tylotornota — chelz arcuate, curious, spined.
= Fiistoderma physa.

se below.

Styli — oxea — chele — rhaphides.

Strongyla.
Tylota — acanthoxea — chelz arcuate — sig-
mata — trichodragmata — curious spined

bodies (transformed chelze? or forcipes?).

26 PORIFERA. IIL

1905. Histoderma vesciculatum Dendy (Rep. of the
Pearl Oyster Fisheries of the Gulf of Manaar,

Part IU]; 166° PU XP tips, S—o) ieee es Oxea — strongyla — chele palmate.
1908. Joyeuxia Belli Kirkpatrick, (Nat. Antarct. Exp.
Nat. Hist. IV, 41, Pl. XVI, figs. 1—5a)...... Strongyla.
Histodermella Ingolfi mihi.................... Tylota — acanthoxea — chele arcuate — sigmata.
Flistodermella cortacea mihi .................. Strongyla with spinulous ends — acanthostrongyla.

Of these species Cornulum ascidioides Frstdt. is shown above to be identical with Azstoderma
physa O. Schmidt. I have also examined a piece of the type-specimen of Cornulum enteromorphordes
Frstdt., and this species proved to be identical with — Myxilla fimbriata Bow., which for the rest
may already very well be seen from the description. The specimen, which Fristedt had to examine,
was of an elongated shape, and this in connection. with the rather strong dermal membrane of this
species has led him to refer this typical A/yxilla species to Cornulum. Hereafter these two species
of Cornulum must be dropped. — Sideroderma Zitteli Lendenfeld scarcely belongs to the group of
sponges here in question.

The remaining species will have to be distributed in the four genera treated above, Histoderma,
Flistodermella, Inflatella and Cornulum. After Carter had established the genus Cornulum with
the typical and sole species /extile, this genus has hitherto only contained the same species, the two
erroneous species of Fristedt excepted. With a generic diagnosis as given above, in which the
distinguishing characters are first the palmate chele, and next the dendritical or reticulate skeleton,
formed of strong fibres, two of the above enumerated species, viz. simgaporense*) and vesciculatum must
belong to this genus, and the genus seems very natural. Histodermella, which I have founded mainly
on characters in the spiculation and for which the typical species is /ugolf, also includes, besides the
two species described here, the Hstoderma natalense established by Kirkpatrick in 1903.

The above enumerated species will, according to the facts mentioned, have to be distributed

in the following way:

Eistoderma: Fiistodermella: Inflatella: Cornulum :
appendiculatum Catt. natalensis Kirkpatr. pellicula O. Schmidt textile Cart.
physa O. Schmidt Lngolfi mihi virtdis Tops. singaporense Cart.
philyctenodes Cart. (vide — cortacea mihi tubulosa Tops. vesciculatum Dendy.
remark on page 27) Belli Kirkpatr.

naviceligerum Dendy
verrucosum Cart.
polymasteides Catt.
clavilobatum Cart. (belongs
perhaps not here but
may be an Esferiopsis)

Topsent has (1.c. 1904, 198) established a new genus Phlyctaenopora with one species, distorquis,

) Dendy (1995, 1. c.) has shown, by examination of Carter’s type specimen, that the species has chelz.

PORIFERA. III. 27

which, according to the author, should be placed near to H/zstoderma; I cannot express myself more
particularly about this species, but its relationship with the forms here in question seems to me some-
what doubtful.

The four genera mentioned are distingushed among the Myxzlleae by the megascleres being
the same in the dermal skeleton and in the skeleton of the inner body; this at all events holds quite
good with regard to Histoderma, Histodermella and /nflatella; among the species of Cornudwm it holds
also good for textile; in singaporense and vesciculatum there are, to be sure, two forms of megascleres,
but they are both diactinal, and they seem not to be sharply divided with regard to their occurrence
in the sponge-body. The four genera are certainly nearly related to each other, and as their starting
point I think we may take Histoderma as most probable, which shows the least deviating structures;
as the genus nearest related to this I take /zflatella, which, especially in the skeletal structure, presents
the greatest accordance, and on the whole mainly differs only in the want of microscleres, a
difference which, when the other structures agree, is of very slight consequence, indeed even
the right of /zflatella as a separate genus is perhaps doubtful, but at present I think, there is
some reason to keep it. Also Histodermella must be nearly related to Histoderma, one species, /ngolfi,
shows both in its exterior and in the skeletal structure great agreement; the curious, spined spi-
cules which are present in this genus, are somewhat surprising, but I think they must probably be |
taken to have their origin from original special skeleton spicules. Cormudwm stands a little more
apart, distinguished by its palmate chele. — I thus take these four genera to be nearly related and
to represent a type of A/yxilleae in which the original skeleton spicules have disappeared. As said,
Fiistoderma might be thought to form the starting point; the genus outside the group, nearest related
to Histoderma, is perhaps Hymedesmia (= Leptosia Tops.); in several species of this genus we find a
strong dermal skeleton formed of diactinal spicules, and at the same time the inner skeleton, consisting
of the basal acanthostyles, may be very little developed; the acanthostyles may be present in so small
numbers, that great care is necessary to avoid mistakes, just in Wymedesmia-species of this latter structure
we find at the same time a strongly developed dermal skeleton which also has well developed fibres
going from the dermal membrane inwards, and here consisting of the same diactinal spicules which
form the dermal skeleton itself. Finally such species may have long, tubular papille (e. g. Wymedesmia
filifera O. Schmidt, and several other species). — It is perhaps a question whether Histoderma phlycte-
nodes Cart. will not prove to be a Hymedesmia. — When now such species get quite roundish and
grow without attachment, as e. g. H. appendiculatum, the elimination of the acanthostyles is easily
understood, and the transition to the freely growing species is formed by such attached species as for
instance Histoderma physa. The genus Melonanchora seems to me to form a beautiful and interesting
instance of the opinions here advanced; one species of this genus has the spiculation and skeletal
structure typical for the A/yxilleac, with skeletal styles and diactinal dermal spicules; these latter,
however, form a very dense dermal skeleton, and the species has oscular and pore-papille; the other
species of the genus has a similar construction, but the skeleton spicules have disappeared and the

whole skeleton is formed of dermal spicules.
4*

28 PORIFERA. III.

Finally I may direct attention to the fact, that I have in the present work placed the
genus H/ymedesmia in the subfamily Actyoninae, which perhaps might seem to go against the views
given above about the relationship of this genus to the group treated here; yet this is not so, since
firstly, the subfamilies AZycalinae and Ectyoninae, as I have already mentioned earlier, are scarcely
quite natural, and even if so it was not impossible, that genera, which on account of their characters
must now be placed in the Mycalinac, should be thought to have originally been derived from
Ectyonine forms.

In the first part of this work I broke up Carter’s Phlocodictyinae and placed its two genera
Phloeodictyon and Oceanapia in the Renierinae and Gelliinae respectively. In a work published in 1905
(Rep. of the Pearl Oyster Fisheries of the Gulf of Manaar, Part III, 165) Dendy keeps the subfamily
Phloeodictyinae under the family Desmacidonidac, and he refers to it the genera Phloeodictyon, Oceana-
pia, Huistoderma, Stderoderma and Amphiastrella. His reasons for keeping these forms together
are mainly the same as those of Carter on founding the group, viz. the hard dermal layer
and the presence of fistulae, but on account of the chele in Histoderma Dendy now removes the
group to the Desmacidonidae. In Part I of this work pag. 56—57 I gave the reasons which seemed to
me to necessitate the breaking up of the Ph/ocodictyinac, and the same reasons are still valid. While
Dendy thus lays stress on the outer shape and the presence of a solid dermal layer as the distinguishing
characters, but pays no attention to the spicules, I on the contrary follow the opposite way and take
first, as the most important character, the spicules and what may be deduced from them with regard |
to the relationship of the forms. Dendy would also have difficulties in delimiting his subfamily;
Phloeodictyon and Petrosia are, as I have already declared (Part I, l. c.), nearly related; Thiele says
(Zoologica XXIV, 2, 1899, 19) that Phloeodictyon (Rhizochalina) medium is an intermediate form;
Melonanchora, which has a solid dermal layer and papille should, I think, also be referred to the
Phloeodictyinae and the same holds good with regard to several Wymedesmia-species; also some species”
of Gellius should be placed here according to the views of Dendy. On the other hand, I think that
the spicules give good hints towards a natural grouping; the oxea present in Phlocodictyon are spicules
typical for the Homorrhapidae; Oceanapia and the species of Gellius, which are provided with a solid
dermal layer, have oxea of quite the same kind, and these together with their microscleres refer them
to the Heterorrhaphidae. The facts are quite otherwise with regard to the spicules in the four genera
in question; their spicules are diactinal (when fully developed), but of quite another type from those
occurring in the Homorrhaphidae and Heterorrhaphidae. That this is the case is shown, and beyond
doubt, by the development, since while the spicules in Homorrhaphidae and Heterorrhaphidae are really
diactinal, and also originate in this form, the spicules in the four genera mentioned are on the
contrary only secondary diactinal, but originate as monactinal; they have thus a development quite
as the dermal spicules in other A/yxilleae, as 1 have described in Part II of this work, pag. 125. Sy
therefore take it to be quite certain, that these genera belong to the A/y-xilleae, and that their spicules
answer to the dermal spicules in the more typical A/yxilleae, but here form the whole skeleton, of
which the interior skeleton however is generally weak. The facts present in A/clonanchora emphysema
seem to me in the highest degree to confirm this view. The occurrence of chelae also shows that

these genera have nothing to do with Phlocodictyon or Occanapia; that the chele may sometimes

PORIFERA. IU. 29

disappear does not invalidate the value of this character. — Dendy has also in his subfamily Phloeo-
dictyinae the genus Amphiastrella with the species bzrotulifera Cart.; this species has birotulee for micro-
scleres and otherwise a structure almost the same as a H/istoderma — it shows especially a striking
resemblance, both in outer shape and in structure, to Hzstodermella coriacea —; this species certainly
belongs to /otrochota, but is a species in which only the dermal spicules are present, and if we form

a special genus for it, this genus must be placed near to /otrochota.

After the manner in which I understand the classification of the above-mentioned forms, we
will thus in the various families find the phenomenon, that certain forms have a specially developed
dermal skeleton, as a rule together with a reduction of the inner skeleton and occurrence of longer
or shorter papilla, by which these forms, in spite of their belonging to different families, get a certain
mutual resemblance. It is then an obvious conclusion, that a common factor must be of influence,
but it seems not possible in our present state of knowledge to point out such a factor. It is easy
enough to understand that all these sponges get provided with papillz, since the hard dermal layer,
furnished with close-lying spicules is not adapted to be pierced by pores and oscula and there must
therefore be special contrivances for these, viz. the fistulae or appendages, and somewhat similar reasons
hold good with regard to the reduction of the inner skeleton. But the cause of the development of
the hard dermal layer is therefore not explained, and the only thing, that can be said, is that it seems
to be in some connection with the fact, that these forms show a tendency to get free, without attach-
ment, or at all events without attachment by a fast-grown basis. The forms which are attached, either
with a broad base as Histoderma physa, or by a peduncle as two of the /z/latella-species, have no
specially strong dermal layer; in the quite free forms as most Phlocodictyon-species, Oceanapia, Histo-
dermella, especially coriacea, and Amphiastrella, the dermal layer on the contrary gets very strong

and solid.

Grayella Cart.
(Yvesta Topsent, 1892)

The external shape varying from thinner or thicker incrustations through massive or cushion-
shaped forms to more or less erect and finally quite erect, club-shaped, stalked and sometimes branched
Jorms. The skeleton consisting of, often rather thick but loose, fibres, formed of smooth spicules; in the
incrusting and massive forms the fibres radiate from the base upwards and outwards, in the erect there
as formed a central axis from which fibres radiate to the surface. The dermal skeleton consisting of
tangential, generally very close-lying, spined spicules, making the dermal membrane very firm. Spongin
present or wanting. Spicula: megasclera; the skeletal spicules are smooth, they are most frequently
diactinal, tornota, strongyla or tylota, but they may be monactinal, styli; the dermal spicules are spined,
monactinal or diactinal. Microsclera are chele arcuate, to which may be added sigmata; sometimes

sigmata are found solely, and microsclera may be quite absent.

30 PORIFERA. IIL.

1. G. pyrula Cart.
Pl. II, Figs. 15—19, Pl. V, Fig. 2.

1876. Cometella pyrula Carter, Ann. Mag. Nat. Hist. 4, XVIII, 388, Pl. XIV, fig. 20, Pl. XV, fig. 38.

1885. Sclerilla arctica Armauer Hansen, The Norwegian North Atl. Exp. XIII, Spongiadze, 12, Pl. II,
fig. 4, Pl. IV, fig. 15.

1885. Sclerilla dura Armauer Hansen, ibid. 13, Pl. II, fig. 5.

1892. Yvesia pedunculata Topsent, Résultats des camp. sc. du Prince de Monaco, Fase. II, 105, Pl. V, fig. 6,
Pl. X, fig. 17.

1903, Yvesia lobata Arnesen, Bergens Mus. Aarb. 18, Taf. II, Fig. 7, Taf. V, Fig. 1, Taf. VI, Fig. 2.

1904. Yvesia pertusa Topsent (non pertusa Tops. 1892), 1. c. Fasc. XXV, 196, Pl. XV, fig. 20.

1909. Grayella pyrula, Lundbeck, Meddel. om Gronland, XXTX, 443.

Erect, club-shaped, generally with a shorter or longer peduncle, above sometimes divided into a
couple of branches, or somewhat lobate; sometimes tt may be compressed. Surface smooth, densely beset
with small, round or oval, more or less distinct pore-areas; the dermal membrane ts stretched over the
pore-areas as a thin membrane, between these tt is not sharply marked, resting on the ends of the fibres
of the main skeleton. The pores are found in the pore-areas; oscula spout-shaped, present in varying
numbers on the upper part, or scattered. The dermal skeleton formed of close-lying, tangential acantho-
styli; the pore-areas have only chele. The main skeleton consisting of a central axis from which fibres
radiate to the surface more or less regularly; there are no transverse fibres, but between the fibres lie
scattered acanthostyli. Spicula; megasclera; the skeletal spicules smooth tornota 0-357—0'58"", the

dermal spicules acanthostyli o-119—0'196"" ; microsclera chele arcuate 0:021—0'0257™".

Of this interesting species we have a somewhat considerable material of specimens of various
sizes. The species is always erect and more or less distinctly club-shaped, and the deviations which
may occur are easily traced back to the club-like shape. The small specimens are all regularly club-
shaped with a shorter or longer peduncle; it is when the sponge grows larger that the shape may
vary somewhat, thus the upper part of the body may be thicker or thinner in relation to the peduncle,
the sponge may be high and slender or relatively short and thick, in the latter case it may be without
any pronounced peduncle, only narrowed below; further it may be divided into a couple of branches
in its upper part, or be more irregularly lobate, or finally it may instead of being round be rather
strongly compressed. All previously described specimens are small, and they all have also a club-
shaped exterior, only the specimen described by Armauer Hansen lc. is larger and shows the
branched and compressed shape. One of the smallest of my specimens has a height of r11™™, the pe-
duncle is 15™" thick and the upper part about 5™™ thick; then we have specimens of all sizes up-
wards, the largest has a height of 50™™ of which the peduncle makes the half part; this latter, which
is rather thin, has a diameter of about 2™", and the upper part is about 10o™ in thickness. The
peduncle is slightly dilated below and shows here a surface of attachment, but most specimens are torn
from the substratum, a single one sits on a fragment of a mussel-shell. The consistency is rather
hard and somewhat elastic, but it may be different according to the degree of contraction; when the

sponge is strongly contracted, as is often the case, the consistency gets very hard. The colour (in

PORIFERA. III. 31

spirit) is whitish yellow, sometimes somewhat greyish. The swz/ace has, as commonly in the genus
Grayella, a very characteristic aspect, being densely beset with pore-areas. These areas are circular
or generally oval and have a slightly elevated edge which surrounds the somewhat immersed pore-
membrane. Such is the structure in the specimens which are least contracted, but as a rule the
sponge is more highly contracted, and then the pore-areas become indistinct or are only seen as small
tubercles, and when the sponge is very strongly contracted they nearly quite disappear, and at the
same time the surface becomes rugose or wrinkled. For the rest the surface is all but smooth, the
spicules not being projecting or only to a very slight degree. The dermal membrane is in the pore-
areas a thin membrane, between the areas it is not sharply bounded inwards, and it is here richly
provided with spicules. Pores and oscula: The pores lie in the mentioned pore-areas in a number of
about ten or more in each area, they are circular or oval and were measured from quite small up to
oog™" in largest diameter; the pore-areas have a greatest size of o5™". The oscula are spout-shaped,
as the opening is surrounded by a conical collar, supported by spicules. .The number of oscula is
various, in the small specimens there is most frequently only one osculum, which is then placed at
the upper end, but in the larger specimens there are several oscula, in a single specimen even eight.
The canal system seems to be very lacunous; there are especially extended cavities somewhat below
the surface, and they are extended somewhat parallel to the surface; they evidently belong to the
excurrent system, as they are in direct connection with the oscula. If a piece of the skin is cut off,
the openings of the incurrent canals, which are vertical to the surface, may be seen below the pore-
areas by aid of the microscope. These structural features are tolerably observable, when the sponge
is not too strongly contracted, but often the specimens are contracted to so high a degree, that these
structures are quite indistinct, at the same time that the pore-areas on the surface are closed and dis-
appearing. The sponge is evidently able to contract itself very strongly, and even the least contracted
specimens in my material are certainly contracted to no slight degree; the structures seem to show
that they are able to be considerably more distended, and the inner cavities, the pore-areas and the
canals are in this state certainly considerably larger.

The skeleton: The dermal skeleton consists of close-lying, tangential acanthostyles, which lie
in more than one layer; they are only found in the membrane between the pore-areas, while the
membrane of the pore-areas themselves is quite devoid of them; they do not form any real reticulation
but by their arrangement around the pore-areas a kind of network is however formed. In the pore-mem-
brane, as said, no acanthostyles are found, but here chelez occur in great numbers. The maiz skeleton
is of a dendritical structure; upwards through the peduncle and up towards the upper end of the
sponge goes a spicula-axis, and from this fibres issue which go out to the surface and at the same
time branch somewhat; outermost they are spreading and support the dermal membrane, but do not
project beyond the surface; as the outermost spicules in the fibres do not go to the pore-areas, but
only to the membrane between them, they become partly arranged circularly around the pore-areas,
as may be seen, when a piece of the skin is cut off and examined from above. A transverse section
of the sponge shows the fibres radiating regularly from the axis to the surface. Between the fibres
no connecting fibres are found, but some scattered spicules occur between them; these spicules

are all acanthostyles, while the fibres are formed exclusively of tornotes. Downwards on the peduncle

32 PORIFERA. III.

the layer of tissue outside on the axis is thin, but the skeleton is of the same construction, with
radiating fibres. The skeleton in the wall of the oscular cones is formed of a dense layer of tornotes
all parallel to the longitudinal direction of the cone; they are partly divided into bands or fibres; this
skeleton is formed in such a way that the fibres going to the surface continue out in the oscular cones
at the places, where oscula are found. On the outer side of the oscular cone there is found a layer
of acanthostyles, and further there are many chelze in the wall. This structure of the oscular cone ©
shows, that it is not formed of the dermal membrane solely. As a rule the spicular axis is very thick
and strong, it is thus in one of the larger specimens 2™ thick below in the peduncle, and above, at
the upper end, 06™" thick. The skeleton is constructed in the described way in the specimens where
it is regular, but a good deal of irregularity may occur, I think partly caused by the presence of the
inner cavities. Between the ordinary fibres some very thick ones may occur, which present themselves
as branchings of the axis; the fibres going towards the surface may be curved in different ways, as
they bend round about the cavities, and they may bend round to such a degree, that they do not go
upwards but downwards. Some of these irregularities are certainly due to the contraction, and I think
the skeleton would show more regularity, if it was examined in a sponge in a quite distended condition. —
Spongin is found in the spicular axis, especially below, towards the base, but the amount is only
slight, and I could not observe any spongin outside the axis.

Spicula: a. Megasclera; 1. The skeletal spicules are tornota, they are straight or slightly,
and then as a rule somewhat irregularly, curved, they are slightly fusiform and have somewhat short,
sharply pointed ends; the length may vary a little in various individuals, it is 0°357—0'58™", and the
thickness may in all vary between o005 and oorr™", by far most frequently it lies between 0007 and
o'008"™", The tornotes sometimes show a quite slight tendency to become polytylote. The fully developed
tornotes have quite equal ends, but quite fine developmental stages were observed, and these were
styles; when they have grown a little older, they have still unequal ends, but they get equal-ended
already at an early stage. 2. The dermal spicules must be termed acanthostyli, as one end is
pointed, but the apex is short; sometimes, but rarely, the apex is indistinct or quite wanting, so that
the spicules are near to, or are really strongyles. They are more or less curved, and it is worthy of
note, that the curvature nearly always lies nearest to the rounded end; the spicules are distinctly
fusiform. The spinulation is dense and coarse, the spines have a length of about half the diameter
of the spicule. The spinulation may vary somewhat with regard to density and the size of the
spines and this is in relation to the variation of the spicule in size, in such a way, that the larger the
spicule is the more densely it is generally spined, and the larger are the spines. To be sure these
variations may generally be found in the same individual, but there may, however, be the difference
between the individuals that in some the smaller, in others the larger spicules are by far the most
numerous, in a single specimen the acanthostyles are on an average more diffusely spined than in
the others. The length of the acanthostyles is o119—o'196™" and the thickness in the middle, the
spines not included, ooo5—oo1r4"". A number of developmental forms in different stages were present,
the finest of them being already distinetly and somewhat strongly spinulous; the developmental stages
are all distinctly monactinal. As said above the tornotes form the fibres, while the acanthostyles form

the dermal skeleton, but are also found in the interior of the body, especially between the fibres.

PORIFERA. III. 33

b. Mitcrosclera; these are of one form, chele arcuate, they have a curved shaft, the free middle
part of which is more than one third of the length of the chela, the tooth is elliptical, of the same
length as the pointed lobe-shaped ale. The length is oo21—o0257™", the diameter of the shaft is
0'70028™™, The chelz occur richly especially in the pore-areas and the oscular wall, but they are also
otherwise found round about in the tissue.

Embryos: In several specimens embryos were found round about in the tissue, and they are thus
not only found innermost, close to the axis, as declared by Carter l.c. They are globular or oval,
of an average diameter of about o'29™. Most of the examined specimens contained no spicules, but
some single were developed so far, that they contained spicules; these were dermal spicules, and they
quite resembled the developmental stages of the dermal spicules in the grown sponge. It is worthy of
notice, that the first occurring spicules here are the spined dermal spicules, while elsewhere in the
Myxilleae it is the skeletal spicules which occur first.

Remarks: As 1 have examined preparations of Carter’s type-specimen, the identification is
certain. For the rest the description given by Carter is by far the best of all the descriptions published,
as he describes the skeleton and the inner cavities in somewhat detail. The species is also rather well
recognizable after his description, when the curious, diagrammatic way in which Carter made figures
of the exterior, is borne in mind. The points on the surface which Carter mentions and figures, are,
of course, the closed pore-areas; he mentions that they form low conical projections, which are formed
of acanthostyles “arranged in a whorl-like manner” and he figures this structure. Anything similar
I have not found in my specimens, but I think, that by a certain degree of contraction the spicules
around the pore-areas may very well present themselves in a way answering to Carter’s expression. —
Armauer Hansen’s type-specimens of Sclerzlla arctica and dura I have also examined, and they
proved to be the present species; his figure of the acanthostyles as oxea is erroneous. Armauer
Hansen concludes with a remark which shows, that he has well seen the conformity of his two
species, and the remark at the same time is very curious as he says: “Probably it would be more
correct to assign them to one species”. I have also examined the type-specimen of Arnesen’s Yvesza
lobata. — I also refer Topsent’s Y. pedunculata and the same authors Y. pertusa from 1904 (but
not Y. pertusa 1892) to the present species; the first named species has relatively small and somewhat
diffusely spined acanthostyles, but this is a character, which according to my observations may be found
in G. pyrula, and otherwise the two species exactly conform. VY. fertusa Tops. 1904 seems to me to
be quite the same as the present species, and I really do not understand, why Topsent refers it to
his Y. pertusa established in 1892, which latter has typical acanthoxea as dermal spicules.

Locality: Station 4, 64° 07' Lat..N., 11° 12’ Long. W., depth 237 fathoms; station 8, 63° 56' Lat. N.,
24° 40' Long. W., depth 136 fathoms; station 27, 64°54’ Lat. N., 55° 10’ Long. W., depth 393 fathoms;
station 57, 63° 37’ Lat. N., 13° 02’ Long. W., depth 350 fathoms; station 85, 63° 21' Lat. N., 25° 21’ Long. W.,
depth 170 fathoms; station 94, 64° 56' Lat. N., 36° 19’ Long. W., depth 204 fathoms; station 95, 65° 14’
Lat. N., 30° 39’ Long. W., depth 752 fathoms; further it has been taken on 63° 15’ Lat. N., 9° 35’ Long. W.,
depth 270 fathoms and 61° 23' Lat.N., 5° 04' Long. W., depth 255 fathoms (Wandel), and East of the
Far6de Islands, depth about 150 fathoms (Th. Mortensen). In all twelve specimens. The localities are

situated in the Denmark Strait, between Iceland and the Farée Islands and South of the Farée Islands.
The Ingolf-Expedition. VI. 3. 5

PORIFERA. II.

34

Geogr. distr. The species is earlier known from the following localities: 65 miles North North-
West of the Orkneys, depth 290 fathoms (“Porcupine”); 61° oo' Lat.N., 4° 49' Long. E., depth 200 fathoms,
Vestfjord, depth 341 fathoms, 74° 08’ Lat. N., 31°12’ Long.E., depth 147 fathoms, (The Norwegian North
Atlantic Exp.); in the Bergensfjord and at Trondhjem, depths 70 to 266 fathoms (Arnesen). If the
interpretation of Topsent’s two species is correct it has further been taken on 43° 47’ Lat.N., 9° 27’
Long. W., depth 160 fathoms, 38° 27’ Lat. N., 28°03’ Long. W., depth 277 fathoms and 37°57’ Lat. N.,
29° 15’ Long. W., depth 106 fathoms. According to these localities the species is distributed between
74° and 38° Lat. N., and between 36° Long. W. and 31° Long. E. with a bathymetrical range from 70
to 752 fathoms. :

2. G. gelida n. sp.
Pl. II, Fig. 20, Pl. V, Fig: 3.

Erect, club-shaped and pedunculated. Surface smooth, densely beset with more or less distinct
pore-areas. The dermal membrane over the areas a thin membrane, supported by the ends of the fibres
of the main skeleton. Pores situated in the pore-areas, osculum spout-shaped, at the summit of the sponge.
The dermal skeleton formed of close-lying, tangential acanthostrongyla, in the pore-membrane there are
only chele. The main skeleton consisting of a powerful median axis from which fibres radiate to the
surface; there are no transverse fibres, but between the fibres le acanthostrongyla. Spicula: megasclera;
the skeletal spicules smooth tornota, more or less polytylote, o40—0'53”", the dermal spicules acantho-

strongyla o-11—o-1g™”",; microsclera chele arcuate 0:024—0°028"™.

This species, of which we have only one specimen, has an outer shape almost like the
preceding; it is erect and slender club-shaped, the lower part forms a peduncle which is broken below.
The thickened part of the body is bent rectangularly above, but this is certainly only due to con-
traction. The length of the sponge, when straightened out, is 50™™ of which the peduncle has 18™™;
the thickness is above 7™. The consistency is hard, and the sponge is evidently highly contracted.
The colour (in spirit) is whitish yellow. The surface is in most places beset with warts or knobs, as
the pore-areas, on account of the strong contraction, are closed and form in this state only small
protuberances; only in a few places they are open and show here the ordinary, characteristic appearance.
There are no projecting spicules. The dermal membrane is a thin membrane over the pore-areas, and
between the areas it is richly provided with spicules. Pores and oscula: With regard to pores and
oscula quite the same holds good, as was said about the preceding species. The pores lie in a similar
way in the sieve-like pore-membranes on the pore-areas; they had a diameter of up to o06™™.
Of oscula only one is found on the specimen, it forms a somewhat high collar just at the top of
the sponge.

The skeleton. This is also constructed quite as in the preceding species. The dermal skeleton
consists of close-lying, tangential acanthostrongyla, they seem mainly lying only in one layer; they are
not present in the pore-membrane, but here chele are found. The main skeleton consists of a power-
ful axis and of fibres radiating out from it, which are divided outwards towards the surface and
support the dermis; the outermost spicules in the fibres meet the dermis especially along the edges

of the pore-areas; connecting fibres are not found, but acanthostrongyla are lying between the fibres;

PORIFERA. III. 35

the fibres are formed of the smooth tornota. The skeleton in the oscular cone is formed of parallel
tornota, outwards it has acanthostrongyla. In the axis a distinctly observable amount of spongin
is found.

Spicula: a. Megasclera; 1. The skeletal spicules are tornota, they are straight and slightly
fusiform and slightly, but rather distinctly polytylote or show at all events an uneven contour;
the ends are rather short and somewhat stubby. The length is o4o—o53™", and the thickness
is oo007—O011™". 2. The dermal spicules are acanthostrongyla, they are slightly curved or some-
times straight and of the same or nearly the same thickness in the whole length; the spinulation is
dense and coarse, and the spines are generally longer than half the diameter of the spicule; the spines
are placed a little more densely at each end. The length is o11—o'19™", and the thickness o1005—0'012™".
Whether these spicules are really and primarily diactinal, I have not been able to decide, as no young
developmental stages occurred; the shape of the spicule does not point towards a monactinal origin,
as also the few older developmental stages, I have seen, are quite diactinal; also the curvature, which
is not localized at one end, but nearly always goes evenly from the middle towards both ends, points
towards a real diactinal spicule, as also does the fact, that the spines on both halves are somewhat
recurved towards the middle, while those standing in the middle are directed straight out. On the
other hand the dermal spicules occurring in the embryos are monactinal (see below under Embryos.)
b. Microsclera; these are of one form, chelz arcuate; they have an evenly curved shaft, lobe-shaped,
somewhat pointed ale and a pointed elliptical tooth of the same length as the ale. The length of
the chelz is o7024—0'028™", and the thickness of the shaft is ooo21—0:0028™. The chele occur
numerously in the pore-membranes and the oscular wall, but also otherwise round about in the tissue.

Embryos: Also in this species embryos were found round about in the tissue in great numbers; they
are globular, of a diameter of about o29™". They were found both with and without spicules. The
spicules are either only chelz or chelz and dermal spicules; the chele seem thus here to be the first
occurring spicules, and next the dermal spicules; in single cases only developmental stages of chelx
were found and some few, thin developmental stages of dermal spicules. The dermal spicules were
not, as is elsewhere generally the case, fine developmental stages, but on the contrary with regard to shape
fully developed spicules; they were, however, smaller than in the grown sponge, viz. 07085™"; both
these spicules and the developmental stages were monactinal with one end pointed.

This species is, as seen from the description, very nearly related to G. pyruda,; the outer shape
and the skeletal structures are the same, only in the spicules is a difference present, but this differ-
ence is constant; the differential character lies in the dermal spicules, these being in gelda always
diactinal and of the same thickness in the whole length, and they are on the whole characteristically
different from the acanthostyli in Ayrwda; if the difference had only consisted therein that the pointed
end here was rounded, no stress would have been laid upon this fact; further the tornota are
distinctly polytylote and have stubby ends, and finally the chele are larger. To be sure I have only
had one specimen of the species, but as this also shows a special condition with regard to locality,
being an inhabitant of the cold area, I have no doubt, that the species is certain and distinct.

Locality: Station 116, 70° 05’ Lat. N., 8° 26' Long. W., South of Jan Mayen, depth 371 fathoms
(bottom temperature + 0° 4 C). One specimen,

5*

36 PORIFERA. III.

3. G. carnosa Tops.
Pl. III, Figs. 20o—21, Pl. V, Fig. 4.
1904. Vvesia carnosa Topsent, Résultats des camp. scient.du Prince de Monaco, Fasc. XXV, 198, Pl. XV, fig. 19.

Plate-shaped and incrusting, or higher and more massive. Surface rugose and wrinkled, without
projecting spicules. Oscula spout-shaped. The dermal membrane a thin film. The dermal skeleton
formed of acanthoxea which are very scattered and often only found im the dermis in very small
number. The main skeleton consisting of fibres which from the base or the middle radiate towards the
surface; there are no transverse fibres, but the acanthoxea are scattered between the fibres. Spicula:
megasclera; the skeletal spicules are polytylote tornota, o.37—047"", the dermal spicules acanthoxea

o137—a'178"™; microsclera not present.

The Ingolf-Expedition has taken three specimens of this species; one grows as a plate on a
specimen of Biemma rosea and has a greatest extent of about 25™", and a greatest thickness of 3™",
the second specimen grows on a shell of Pecten aratus as an incrustation with a greatest extent of 15™™;
these specimens have thus in outer shape a resemblance with the specimens described by Topsent,
which latter, however, reached to a greatest extent of 55™™. The third specimen is a small, oval
body, of a length of 7"; it has two oscular cones in one end, the other end shows a somewhat broken
surface and besides some adhering bottom material; the specimen has thus probably been attached
with this end and has thus been erect. The colour (in spirit) is lighter or darker brown, in one
specimen quite white; Topsent’s specimens were blackish, one or the other of the colours is certainly
due to the action of alcohol. The consistency is somewhat firm and elastic. The sawz/ace is somewhat
wrinkled and folded, but otherwise smooth. The dermal membrane is thin but somewhat solid, it is
not easily separable, and it is provided with spicules only to a very slight degree. Pores or pore-
areas I have not seen, probably they are closed and must have disappeared in the folded and wrinkled
dermal membrane. Of oscezla as said two were found on one of the specimens, while the two others
showed none.

The skeleton. The dermal skeleton is in this species almost not developed, as there are, at
all events in by far the most places, only rather few, scattered acanthoxea in the dermis. The
main skeleton has a somewhat similar structure as in the other species; it consists of fibres which
radiate towards the surface, are branched and support the dermis, but do not pierce it; the outermost
fibres are as a rule thin, but here and there also very thick fibres go to the surface; in the interior
the fibres are very thick and strong. The fibres go in the plate-shaped specimens not parallel from
the base to the surface, but they seem to have a more or less extended centre at the base, from
which they radiate to the surface; in the erect specimen there are thick spicular parts at the base
and in the middle, from which fibres radiate out. There are no transverse connecting fibres, but
acanthoxea are scattered between the fibres. The fibres consist of tornotes; the skeleton in the oscular
cones are formed of fibres of tornotes, but no acanthoxea were seen here. Spongin was not observed.

Spicula: a. Megasclera; 1. The skeletal spicules are tornota, they are straight, the ends are
somewhat long-pointed, but outermost often a little stubby; they are distinctly polytylote. The length
is 0'37—0'47"" and the diameter is between o005 and o'007™". The ends are generally not equal, but

PORIFERA. III. 37

one is a little shorter and a little more stubby, the other longer and more pointed; the fine develop-
mental stages are quite monactinal, and the thinner spicules or developmental forms are generally
more pronounced polytylote than the thicker. 2. The dermal spicules are acanthoxea, they are
evenly curved, sometimes the curve forms an angle in the middle of the spicule; they are fusiform
and long-pointed, tapering from the middle outwards. The spinulation is dense, the spines are largest
in the middle but decrease in size outwards. The length is 0137—o'178™" and the diameter o004 —
o7007™, Some developmental stages were found, which were quite fine and more weakly spinulous.
The tornotes form the fibres, the acanthoxea occur in the dermal membrane but much scattered, and
besides they occur in the tissue, between the fibres. Jicrosclera are not present.

: I think it quite certain that this species is identical with carnosa Tops. as the description
answers precisely; the outer shape, the skeleton and the spicules agree, only the spicules are declared
to be a little larger, the tornotes 0°53—o0°60™" with a thickness of oo007—o‘o10™ and the acanthoxea
o16—o18™= with thickness o005 07006", but this difference is certainly of no consequence with
regard to specific distinction; a fact which also contributes to the settlement that the species are
identical is the communication by Topsent, that at the surface: “s’accumulent de large cellules

», since my specimens show the tissue at the

sphéruleuses 4 sphérules dissociées, grosses, brillants...
surface filled with densely crowded, curious, rather large, elliptical granules’).

Locality: Station 9, 64° 18' Lat. N., 27° oo' Long. W., depth 295 fathoms; station 85, 63° 21’ Lat. N.,
25° 21' Long. W., depth 170 fathoms; station 89, 64° 45’ Lat. N., 27° 20’ Long. W., depth 310 fathoms. The
localities lie near to each other in the Denmark Strait.

Geogr. distr. The species has earlier been taken at the Azores at 38° 46' Lat. N., 27° 17’ Long. W.,

depth 543 fathoms and 38° 35’ Lat. N., 28° 06’ Long. W., depth 664 fathoms (Topsent. 1. c.).

I shall here try to give a list of the Grayella species in the consecutive order in which they

have been described, at the same time noting their spiculation and outer shape:
Spicules :
skeletal. dermal. microsclera. shape.

1862. G. rubiginosa O. Schmidt (Spong. d.
adriat. Meer. 72, Taf. VII, Fig. 5)
FLY RIG) ce et pa ORS. tylota styli + crust.

1864. — albula Bow. (Mon. Brit. Spong. II,
253, III, Pl. XLV, figs. 21-24) (Hal-

La) |g 77 a ee ec styli styli chelze arcuate crust.
1869. — cyatophora Cart. (Ann. Mag. Nat.
Paes, TV, 150, PROVE oi strongylotornota oxea + massive crust.

1870. — papillosa O. Schmidt (Grundziige
einer Spongienf. Atl. Meer. 57) (Crz-
ef 2 SR ee ey 3 OSA eee strongyla oxea chele arcuate tuberous.

1) What these granules may be I cannot say; whether they really have something to do with Topsent’s cellules
sphéruleuses is, I think, doubtful.

38 PORIFERA. IIL

Spicules:

skeletal. dermal. microsclera. shape.
1876. G. pyrula Cart.(Ann. Mag. Nat. Hist.
4, XVITI, 388, Pl. XIV, fig.20, Pl. XV,
fig. 38). (Cometella) .. 0. ccjcn neues tornota styli chelz arcuate club-shaped.
1882. — armigera Bow.) (Mon. Brit. Spong.
IV, 73, Pl. IV, figs. 1o—17) Hymenta-
ADIBY 50 va es hes AS a eat oxea styli chelze arcuatee crust.
1885. — dura Arm. Hans.(Norw. North. Atl.
Exp. XIII, 13, Pl. II, fig. 5)(Scderilla) oxea oxea chele arcuate club-shaped.
« —arctica Arm. Hans. (ibid. 12, Pl. II,
fig. 4, Pl. VI, fig. 15 (Sclerilla)... oxea oxea | chelee arcuatee club-shaped.
« —membranacea Arm. Hans. (ibid. 4,
P1.I, fig. 11, Pl. VI, fig. 12.) (Renzera) ? oxea ? ?
1892. —- pedunculata Tops. (Résultats des
camp. sc. du Prince de Monaco, II, 105,
PLV, fig.6, Pl. X, fig. 17.) (Yvesta).. tornota styli chelz arcuate club-shaped.
« —/fallaxTops.ibid., 106, Pl.VI, fig. 13,
Pl. X, fig. 14.) (Yvesta) ........... tornota styli chelz arcuatee massive.
« — Hanseni Tops. (ibid., 106, Pl. VI,
fig. ga, Pl. X, fig. 13) (Vvesza)..... tylota styli chelze arcuatee, crust.
sigmata
« — Richardi Tops. (ibid.,-107, Pl. X,
6. 25) '( LOR ao ae Pe awe tylota styli chele arcuate, crust.
sigmata
« — Guernet Tops. (ibid., 105, Pl. III,
fig. 7, Pl. X, fig. 16) (Yvesza)..... styli styli sigmata thick crust.
« — Ridleyi Tops. (ibid., 107, Pl. X, fig.
TQ) if SUCHAY oe icles ane tylota with spi- tornostrongyla + crust.
nulous ends
« — pertusaTops. (ibid., 107, PLIV, fig.
10, Pl. X, fig. 18.) ( Yvesza) (non fer-
HIE CT ODE ZOOM) oa eee ee tornota oxea chelee arcuate crust.
« —lngutfera Tops. (ibid. 108, Pl. X,
figs. 1o—11) (Yvesta)............ strongyla oxea chele arcuate massivecrust.
« —vosacea'Tops. (Arch. Zool. exp. et
gén. 2, X, XXIII) (Vvesza)....... tornota styli chelz arcuate thick crust.
1898. — alecto Tops. (Mém. de la Soc. Zool.
de Fr. XI 248, fig. 2e—e”)/ Yvesza). strongyla oxea, with large -S massive.
spinulous spines
and transform-
ations to asters
1903. — polymastia Thiele (Arch. fiir Natur-
gesch. 1903, 391, Taf. XXI, Fig.
2h B-~€) Kg eres SRR TS ee strongyla styli chele arcuate semiglobular.
« —mammillata Arnesen (Berg. Mus.
Aarb. 1903, 17, Taf. II, Fig.6, Taf. VII,
BIG Bi) f OEE) od oo 5 segs ance Uae tylota, styli to chelz arcuate massive.

single styli strongyla

1) Perhaps a Crella. *) This species might perhaps be a Cred/a, but the point cannot be decided, only the dermal mem-
brane being known.

PORIFERA. III. 39

Spicules:
: < skeletal. dermal. microsclera. shape.
1903. G. lobata Arnesen (ibid. 18, Taf. II,
Fig. 7, Taf. V, Fig. 1, Taf. VI, Fig. 2)
NGS TN ER DSS eR OED oxea styli chelze arcuate _club-shaped.
1904. — carnosa Tops. (l.c. Fasc. XXV, 198,
ieee P10) / YUCSIC). 2s... tornota, oxea + massive.
polytylote
OMG UNS oe eek sins. tornota, strongyla chelee arcuatze club-shaped.
polytylote ,

Of these species, four: G. arctica Arm. Hans. dura Arm. Hans., pedunculata Tops., and lobata
Arnesen, disappear as identical with G. pyrwla Cart. as shown above, (the shape of the spicules of
these species is in the above list given as recorded by the authors); the total number of the species
belonging at present to Grayella is thus twenty, of which two, G. armigera Bow. and membranacea
Arm. Hans. are doubtful.

Cribrella hospitals O. Schmidt (Grundziige einer Spongienf. des Atlant. Gebiet. 1870, 56, Taf. IV,
Fig. 12) was by Topsent (Il. c. 1892, 103) taken to be an Yvesza, and I thought the same (The Danish
Ingolf Exp. VI, 2, 1905, 127); Topsent had also good reasons for his interpretation, but yet it seems
not to be correct, and there is every reason to take this species to be a Stylostichon, as I have de-
clared more particularly (Meddel. om Grénland, XXIX, 1909, 447). Schmidt also says nothing about
the arrangement of the oxea and the acanthostyli in this species, whereas he does so with regard to
his next species C. Zapillosa, and I think it rather sure, that Fristedt’s and Carter’s hospitalis
are identical with Schmidt’s species, and that the species is thus a Stylostichon,; the figure by Carter
(Ann. Mag. Nat. Hist. 4, XVIII, Pl. XIII, fig. 18) of the outer shape of the sponge also points in

this direction.
Subfam. 2. Ectyoninae.

Hymedesmia Bow.
(Leptosta. Topsent, 1892.)

Incrusting and generally very thin forms; sometimes, on account of the manner of growth,
assuming a massive appearance, but also then in reality incrusting. The surface generally simple,
sometimes with more or less developed papille to which oscula and pores are connected. The main
skeleton consists of vertical acanthostyli with their heads based on the substratum; it may be more or
less dense, sometimes rather diffuse and little developed. The dermal skeleton formed of bundles or
Sjibres of dermal spicules, which generally stretch from the main skeleton, or quite from the base, upwards
to the dermal membrane; it may be very differently developed, sometimes consisting of scattered bundles,
sometimes of relatively long fibres, and it is not rarely by far the most developed part of the skeleton.
The dermal membrane itself, which is supported by the outermost bundles of the dermal skeleton, may
be with or without horizontal spicules; it is generally charged with dense-lying chele, often so dense,
that they form a layer. At the base of the sponge there ts a generally small amount of spongin, in
which the heads of the acanthostyli are imbedded. Spicula: megasclera: the skeletal spicules are acantho-

styl, the head ts generally more or less swollen; they always vary greatly in size, and are often divided

40 PORIFERA. III.

into two groups of sizes, large and small; the dermal spicules are as a rule diactinal, generally strongyla,
sometimes tylota, tornota or oxea; in a few cases they are monactinal, styl. Microsclera are chele
arcuate, solely or together with sigmata, rarely sigmata alone, in a single case rhaphides alone; some-

times there are no microsclera.

The species of Hymedesmia are all incrusting forms, as it is a generic character, that the
skeletal spicules are all based on the substratum; the species are therefore all of insignificant appear-
ance, forming flat and generally very thin crusts; only rarely they may assume another appearance,
showing a massive exterior, but this is then due to the manner of growing, such species more or less
enclosing their substratum, which is in such cases loose bettom material, and getting thereby the
massive outer shape, but being in reality incrusting and with all the skeletal spicules fixed on
particles of the imbedded bottom material. The dermal skeleton may sometimes be strongly
developed, giving the sponge some thickness, and this is also the case just in the species appearing
massive, which also contributes to their massive appearance. The main skeleton is very uniformly
constructed, all the acanthostyles having their heads placed on the substratum and being more or
less vertical; only the density in which the spicules are placed may be somewhat different; generally
the acanthostyles are placed uniformly scattered over the substratum, but in some cases this is not
so, the acanthostyles being gathered in small bundles, from which then the fibres of the dermal
skeleton issue, and in the species, which enclose their substratum, this is generally so. The dermal
skeleton, which is less influenced by the incrusting growth, may be a little more varied, and is some-
times by far the most developed part of the sponge; in the thin, incrusting forms, however, it only
consists of more or less scattered bundles or short fibres. In the species in which the microscleres
are chelz, which is by far the greatest number, these may be more or less numerously scattered in
the dermal membrane, and not rarely they form a more or less dense, sometimes very dense, layer;
this feature reaches, I think, its climax in 47. crux where the spined chelz form a very dense layer
constituting a protective mail. When the chele are so strongly gathered in the dermis, I think this
is to some degree due to contraction, a state which generally prevails in spirit material and there-
fore is so often present in the material for examination; when the sponge is living and expanded I
think the chelze would be found much less concentrated; if this is so, it would also be easily
understood, that the chele, when the living sponge is disturbed and contracts, form a strong, pro-
tective layer.

The surface is generally simple, more rarely it bears papillae, which may be very low, conical
warts, or somewhat long papille, or they may finally be very long and thread-like; the papille as a
rule bear the oscula and pores. I think that special adaptations for oscula and pores are also otherwise
often present, but they are often so insignificant, that they are difficult to detect, e. g. the pore-sieves
in H/. Dwjardinit, and when no special adaptations are seen I think the oscula are simple openings and
the pores lie in more or less pronounced groups over the subdermal cavities.

The colours of the species are generally the ordinary yellow, greyish or brownish colours;
more rarely other, more lively, colours are present, as reddish, green or blue.

As said above, some species grow on loose bottom material as sand, gravel, sponge-spicules

and the like; otherwise the numerous species form incrustations on every kind of substratum present

PORIFERA. III. 4t

on the bottom, as large and small stones, shells of every kind, corals, Bryozoa and hydroids, worm-
tubes, other sponges etc. The sheils and other objects are generally dead, but the sponges incrust
also not rarely living Molluscs and Brachiopods. Often several different species grow together on the
same object, and when their outer apperance, as generally, is the same, it may be a matter of no
little difficulty to make out the borders for the different species.

The genus //ymedesmia in its present conception was established by Topsent in 1892 (Arch.
de Zool. exp. et gén. 2. X, XXII) under the name of Zeféosza, but Thiele has correctly shown (Ab-
handl. Senckenberg. naturf. Gesellsch. XXV, 1903, 955), that the genus must bear the name Hymedesmia
Bow. as Topsent enumerates //. zetlandica as one of its species, and this species is the type of
Bowerbank’s Lymedesmia.

Topsent placed the species in his subfamily Dendoricinae, but I prefer to include it, together
with the nearly related Hymenancora n. g. and Leptolabis Tops.t), in the subfamily ctyoninae; the
whole construction of the skeleton points towards the Zctyonznae, the acanthostyli are always much
varying in size and often divided into two different groups; among the A/ycalinae we have no genus
with a similar skeleton; there is also no doubt that Hymedesmia is nearly related to the Ectyonine
genera Stylostichon aud Plumohalichondria.

To the genus Aymedesmia | refer only such species which are quite incrusting and in which
the base of the main skeleton is in one plane, that is to say that all the skeletal styles have their heads
based on the substratum. This character is then the main distinguishing character in contrast to Sty/o-
stichon, in which genus the main skeleton forms columns, and if we wish to have a sharp distinction it
is necessary to make sure, that the main skeleton in Hymedesmia must be quite basally arranged; if the
dividing line is not drawn in this way, we get no sharp distinction, and I am also inclined to think, that
this division is somewhat natural. The group of genera which may here be taken into consideration
are: Hymedesmia, Plumohalichondria, Eurypon (= Hymeraphia) and Microciona. ‘These genera I
understand in the following way: Hymedesmia and Stylostichon are nearly related, but are distinguished
by the character mentioned; a character which is often found in ymedesmia and which may also be
found in Stylostichon is the above mentioned crowding of the chelz in the dermal membrane, so that
a more or less distinct layer is formed; Plumohalichondria stands a little more remote, distinguished
by having smooth, diactinal spicules in the fibres; Zurypon and A@icrociona are still more remote, and
nearer towards the Clathria-like forms; they are, so far as I know them, characterised in contrast to the
three first-named genera by a greater difference between the skeletal and the accessory spicules and
by (generally) monactinal dermal spicules, the chele are (always?) palmate chele, and toxa are very
often present; I think these characters will prove valid in most cases; the two genera are distinguished
from one another by the character that Awryfon has a basally arranged main skeleton, while A/cro-
ctona has columns. Some single species of Ewrypfon without microscleres may perhaps be difficult to
distinguish from some species of Wymedesmia likewise without microscleres, but as a rule I think that
the mentioned characters from the megascleres will be sufficient.

The genus Hymedesmia is rather large, and it was therefore of some importance, if it could
be divided; Topsent has already separated the species with forcipes, forming for them the genus

t) I think ZLeftosastra Tops. and perhaps also Dragmatyle Tops. are likewise to be placed in the Zctyoninae.
The Ingolf-Expedition. VI. 3. 6

42 PORIFERA. III.

Leptolabis; below I have separated off the species with ancore, forming for them my genus Hymen-
ancora; though it is only a small number of species which are thus separated from Aymedesmia, the
division is, however, of importance, making the remaining genus more uniform and natural. The
possibility might also be suggested of dividing the remaining genus into two, containing respectively
the species with and those without microscleres, but such a division I consider as not natural, as
some species of both groups are nearly related; quite the same holds good with regard to the pos-
sibility of separating off the species which possess sigmates, e. g. 17. zetlandica Bow. with sigmates is

nearly related to 7. Bowerbanki n. sp., truncata un. sp. and latrunculioides n, sp. all without sigmates.

1. H. Koehleri Tops.

Pl. V, Fig. 5.
1896. Leptosia Kochlert Topsent, Résultats scient. de la camp. du “Caudan”, 284, Pl. VIII, fig. 7—9.
1904. _ o> Topsent, Résultats des camp. scient. du Prince de Monaco, Fasc. XXV, 188.

Incrusting; oscula present as low and indistinct cones, with a dense skeleton of dermal spicules
in the wall. Spicula: megasclera; the skeletal spicules acanthostyli with a somewhat distinct head, and
spined in the whole or nearly the whole length, o'og—oa 33”, not divided into two groups; dermal spi-

cules polytylote strongyla o:196—o'30"",; microsclera chele arcuate o028—o:050”™.

Of this species, which I refer to 7. Koehleri' Tops. (see below under remarks), we have a rather
large material. The specimens form thin incrustations on stones, some single ones grow on tubes of
Placostegus tridentatus The greatest extent to which my specimens reach is 24™™; the thickness
reaches scarcely o'5™". The colour (in spirit) is generally white, sometimes a little darker and then
greyish brown or light brown. The szz/ace is in the undamaged specimens smooth, without projecting
spicules, but under a good lens it appears finely gritty, which is caused by the styles. The dermal
membrane is an easily separable, thin and transparent membrane; it is filled with microscleres and is
supported by scattered bundles of dermal spicules. ores I have only observed with certainty in a
couple of specimens, and in these they were seen as scattered, circular openings of a diameter of about
0:047"™"; when the pores are normally open they probably lie in groups over the subdermal cavities.
Oscula could in several specimens be observed with a good lens. They are scattered on the surface
and appear as very weakly pronounced and low cones of a diameter of about 1™™. In the centre an
opening appears which is larger or smaller in relation to the degree of opening of the osculum; on
account of the slight thickness of the sponge the opening only appears as a deepening; when the
osculum is closed, the cone appears slightly stellately corrugated. The dermal spicules form an oscular
skeleton, as they lie very close in the wall of the oscular cone and are arranged subparallel, so that
they radiate stellately towards the oscular opening; above the dermal spicules, however, lies the dense
layer of chelz; this layer is only wanting just at the very summit of the oscular cone. Larger and
smaller subdermal cavities or canals may be seen shining through the dermis, especially in the lighter
coloured specimens.

The skeleton. The dermal skeleton may be said for the greater part to be formed of the chelz,

which form a very dense layer in the dermal membrane. Moreover, short and loose fibres or bundles

PORIFERA. III. 43

of dermal spicules stretch, generally in a more or less oblique direction, from the interior of the sponge
out to the dermis; besides, they are also found in the dermis, below the layer of chelz, as scattered
bundles or single spicules; finally they form, as said, the skeleton of the oscular wall, also lying here
below the layer of chela. The main skeleton is formed of the acanthostyli which all have the heads
fixed on the substratum and are vertical; the largest acanthostyli reach with the point up to the
dermal membrane, but in the undamaged sponges they scarcely project beyond it. The smaller styles
are placed between the larger. Spongin was not observed with certainty.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are generally
straight, sometimes slightly curved; they have a somewhat distinct head, and from this they taper
evenly, thus forming a long apex which is often a little more abruptly pointed at the very point.
' The spinulation is somewhat dense in the lower part of the spicule, but becomes more scattered out-
wards, and the outermost part is generally smooth; the longer the spicules are the point is to a
greater extent smooth, and in the smaller spicules the spines are found quite out to the point. The
spines are somewhat reclined. The head is densely covered with spines, which are considerably larger
than the others, and also have a different shape; they are not reclined but more or less straight
radiating, and they are as a rule not pointed but obtuse at the end; this obtuse or cut end is not
rarely somewhat jagged or crenulated. The styles vary much in size and as the intermediate forms
occur somewhat sparingly, the styles would seem divided into two groups with regard to size, but
there is certainly no principal division into two groups. The length varies in all between og and
0'33™, and the diameter at the head, including the spines, varies from oo1g—o035"". With regard
to the size of the styles there may be some difference in different individuals, in some the greatest
length was thus 023™" and the diameter 01024"; when the spicules thus only reach a smaller length,
the mentioned division into two groups is generally still less distinct. 2. The dermal spicules are
rather slender, straight strongyla; the two ends are often a little different, one being slightly thicker
than the other, and sometimes one or both ends are slightly swollen; in other cases the ends are
somewhat narrowed. The strongyla are always polytylote with a row of swellings; this may be more
or less pronounced, but is rarely or never quite wanting. The strongyla have a length of o-196—0'30"",
and a diameter in the middle of o005—o007™. These spicules do not vary much in the various
individuals. b. Microsclera; these are chele arcuate; they have a more or less, but always rather
strongly, curved shaft, the ale are lobe-shaped, the tooth is narrowly elliptical with the end rounded,
and there is a long, narrow tuberculum. The shaft is not cylindrical but somewhat flattened, which
may be present to a higher or lower degree. The chele may vary a little in shape and size in the
various individuals, the shape, however, is chiefly the same. The length is, all variations concerned,
0'7028—o'050™"; as instances of variation in size in various individuals I may note the following:
0°028—0'°038"™", 0°035—0'042™", 0°037—0'°045"" and 0:032—o'050™"; the diameter of the shaft is o7004—
oo1o™ in relation to the size of the chela, and to whether it is seen in front or side view. As said,
the chelze occur in the dermal membrane forming a dense layer; they are also seen singly through
the whole body.

Remarks: | have determined the above species as 7. Kochleri Tops., but not without hesitation.

When Topsent in 1896 founded the species, he laid stress especially on the polytylote strongyles,
6*

44 PORIFERA. III.

but this is not a very safe character, as strongyles more or less polytylote are of frequent occurrence
in Hymedesmia; already when he founded the species, Topsent mentioned, that it varies somewhat
with regard to the spicules, and in 1904 he again states that this variation takes place to a high

degree, the three forms of spicules varying both in size and in shape; according to this I am not at

all sure, that all the specimens mentioned by Topsent belong really to the same species. When I

have determined my species as Koeh/eri, my reason is especially the somewhat robust, conical acantho-

styli, generally with large, somewhat obtuse or crenulated spines at the head-swelling, the polytylote

strongyla with unequal ends and also the shape of the chelz. Now, as already stated, my specimens

may also vary to a certain degree, and the acanthostyli are not always so robust, or with so large

spines at the base as in the more typical specimens, and the possibility, that there may be more than

one, very nearly related species in my material is not quite excluded.

Locality: Station 9, 64° 18’ Lat. N., 27° oo’ Long. W., depth 295 fathoms; station 16, 65° 43' Lat. N.,
26° 58’ Long. W., depth 250 fathoms; station 54, 63°08’ Lat. N., 15° 40' Long. W., depth 691 fathoms;
_ Station 57, 63°37' Lat. N., 13° 02’ Long. W., depth 350 fathoms; station 98, 65° 38’ Lat. N., 26° 27’ Long. W.,
depth 138 fathoms; further it has been taken East and West of the Farde Islands in depths of 250
and 180 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). The localities are situated in the Denmark
Strait, between Iceland and the Farde Islands and East of the latter.

Geogr. distr. Topsent mentions the species from the Bay of Gascogne, depth 648 fathoms,
and from the Azores in depths of 318 to 1350 fathoms. At present the species would thus be known
from about 66° to 38° Lat. N., and between about 2° and 31° Long. W., with a bathymetrical range
from 138 to 1350 fathoms.

2. H. lacera n. sp.
Pl. V, Fig. 6.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules slender acanthostyli with
a slightly marked head, spined only in the lower half part, o:13—0°'51"™", not divided into two groups;
dermal spicules large, generally slightly polytylote strongyla, 0327-047"; microsclera chele arcuate

0°045—0'054"".

Of this species one specimen grows as an irregular incrustation on a worm-tube which is
attached to a Hornera lichenoides, another specimen grows on a mussel-shell; the greatest extent of
the specimens is about 15™", and the thickness is about o5™™ or a little more. The colour (in spirit)
is whitish grey or dirty brownish grey, but it is stated to be light dirty green in the fresh state. The
surface is smooth, without projecting spicules. The dermal membrane is a somewhat solid film.

The skeleton. The dermal skeleton is formed of bundles or short fibres, stretching from beneath
up to the dermis, upwards they are somewhat penicillately spread; moreover, bundles or somewhat
longer fibres are found lying horizontally in the dermal membrane, and finally there are scattered
chelz. The main skeleton is constructed in the ordinary way; the styli are very dispersed. So far as
I could observe there is some spongin at the base.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli, which are very slender
and straight or quite slightly, rarely a little more, curved; the head is generally only very slightly

PORIFERA. III. 45

swollen, and the shaft tapers into a long, fine apex. The spinulation is both in the large and in the
smaller styli restricted to about the lower half part; in the small styli there are, however, generally
some scattered spines more apically. The spines are only somewhat large on the head, outwards they
become small and still further outwards they are small grits, but generally more or fewer larger
spines are found between them. The spines are directed straight out, not reclined. The length is
o'13—0'51™", and the diameter of the head is oo14—o025"™". The styli are not divided into two
separate groups, but the intermediate sizes are rare. 2. The dermal spicules are rather large,
straight strongyla; one end is generally a little thicker than the other, but this feature is not always
distinct; the thicker end, or both ends may be quite slightly swollen; the shaft is slightly polytylote,
but sometimes this is hardly apparent. The length is 0327—047™", and the diameter o7007—o011™".
b. A@icrosclera, these are chele arcuate; they have an evenly, not specially strongly curved shaft;
the tooth is narrow, lanceolate, the ale are of the same length as the tooth, but they are relatively
narrow, they may therefore, in a certain view be of a somewhat claw-shaped appearance, and the
chela may remind one somewhat of an ancora. The length is oo45—0o054™", the shaft is somewhat
flattened, the diameter relatively from 0:0028 to 070057™. The chelz occur rather numerously scattered
in the dermal membrane.

The slender, often straight styli, generally showing some large spines among the small, are
characteristic for this species together with the large dermal spicules and the large chele with
relatively long, narrow ale.

. Locality: Station 113, 69° 31’ Lat. N., 7° 06’ Long. W., depth 1309 fathoms (bottom temperature
+1°0C), one specimen; Forsblads Fjord in East-Greenland, 72° 28’ Lat. N., depth 50—90 fathoms (The
Amdrup Expedition 1900), one specimen. The species must, according to these localities, be a native

of the cold water.

3. H. storea un. sp.
Pl. V, Fig. 7.

Incrusting; surface smooth? Spicula: megasclera; the skeletal spicules somewhat densely spined
acanthostyli with a globular head, the longer of them with a smooth apical part, o'ro—o 30", not
divided into two groups; the dermal spicules polytylote strongyla o:29—0°37%"; microsclera small chele

arcuate recalling in shape the palmate chele, 0-033—0'038”™.

This species grows as extended but thin incrustations on stones; it reaches a greatest extent
of 65™", the thickness is very slight, below o5™". The colour (in spirit) is whitish grey. In the
present state of the sponge the surface is densely and finely hispid, caused by the skeletal spicules,
but this seems to be due to the fact, that the dermal membrane is wanting for the greatest part;
where the membrane is present, the surface seems to be smooth. -The dermal membrane is a thin
membrane, resting on the skeleton below.

The skeleton. The dermal skeleton; the dermal spicules form a skeleton of bundles and fibres
stretching from the basal skeleton up to the dermis; the fibres run more or less obliquely or bend
horizontally under the membrane. The main skeleton is constructed in the ordinary way, consisting

of vertical acanthostyli not placed specially densely. At the base an amount of spongin is present.

46 PORIFERA. IL

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli, they are straight, more
rarely slightly curved, with a distinct, globular, but however only slightly swollen head. The spinu-
lation is dense, consisting of large, more or less reclined spines; on the head, where the spines are
largest, they radiate straight out, and also on the lowermost part of the shaft; the larger styli
become dispersedly spined outwards and have a smooth apical part; the smaller ones are spined in
the whole length, but they have often, however, the spines somewhat dispersed towards the apex.
The length is o10o—o'30™", and the diameter of the head is oo14—0'028™ ; the styli are not divided
into two groups of size. 2. The dermal spicules are straight strongyla; they are of the same
thickness in the whole length and more or less polytylote; one end may be quite slightly swollen.
The length is o29—0'37™" and the diameter o'7005—0°007™. b. Jicrosclera are chele arcuate, they
are rather small and slender, the tooth is narrowly elliptical, the ale are connected with the shaft in
their whole length, viewed from in front they are only slightly incised below, the chela thus
approaches to the palmate chelze; the shaft is slender and evenly but not much curved. The length
is 0°033—0'°038™", and the diameter of the shaft oo002™". The chelz occur in somewhat great numbers
in the dermal membrane.

This species in its acanthostyli somewhat resembles Koehleri, but it has larger strongyla,
and more slender chelz of another shape; from ébaculifera Tops. it is distinguished by the chele.

Locality: Station 105, 65° 34' Lat. N., 7° 31' Long. W., depth 762 fathoms (bottom temperature
+ 0° 8 C); station 125, 68° 08’ Lat. N., 16° 02' Long. W., depth 729 fathoms (bottom temperature + 0° 8 C.);
the species is thus limited to the cold area. The localities lie North and North-east of Iceland.

4. H. lamina n. sp.
Pl. V, Fig. 8.

Incrusting ; surface smooth. Spicula: megasclera; the skeletal spicules acanthostyli with a rather
small, globular head, spined in the whole length, but the spines in the longer spicules very dispersed
towards the point, o:12—0:33"", not divided into two groups; the dermal spicules strongyla, 0:22—0°36"";

microsclera small chele arcuate of a shape reminding one somewhat of palmate chele, ao028”".

Of this species we have five specimens, three growing on two different Bryozoa, one on a
stone and one on a living Brachiopod; it has a greatest extent of 1o—17™", the thickness is about
o5™". The colour (in spirit) is greyish white. The surface is smooth, without projecting spicules.
The dermal membrane is a rather thin, but somewhat solid membrane, resting on the skeleton below.
Some canals were seen shining through the membrane.

The skeleton. The dermal skeleton consists of bundles and fibres of dermal spicules, stretching
from the lower part of the sponge up to the membrane; they have a more or less oblique direction,
and below the dermal membrane they may run as horizontal or nearly horizontal fibres, but there is
no skeleton in the dermal membrane itself; the fibres have many spicules alongside, but they are
however not specially thick. The maz skeleton is formed in the ordinary way, it is somewhat dis-

persed. At the base an amount of spongin is found in which the heads of the acanthostyli are
imbedded.

PORIFERA. III. 47

Spicula: a. Megasclera. 1. The skeletal spicules are straight or very slightly curved
acanthostyli; the head is globular, but not however much swollen, the apex is long and evenly
tapering; the spines are distinct also in the larger styli; the small. styli are entirely spined, in the
larger the spines are very dispersed towards the point, but they are most often present out to the
point, or only a small part of the apex is smooth; more rarely the styli may be smooth for a longer
distance. The length is o:12—0'33™", and the diameter of the head is oo12—0°022™. 2. The dermal
spicules are straight strongyla; they are of the same thickness in the whole length and slightly
polytylote; the length is o-22—o'36™" and the diameter about o005™". The size of the megascleres
may vary a little in various individuals. b. Microsclera; these are chele arcuate; they are small
and of a particular shape, by which they approach somewhat to the chele palmate; the shaft is evenly
curved, the tooth is lanceolate, and the ale are connected with the shaft in their whole length, it is
therefore chiefly only the curved shaft which distinguishes them from the palmate chele. The length
is o1o28™ and the diameter of the shaft about oo02™™, The chelz occur scattered in the dermal
membrane.

This species is characterised already by its chele.

Locality: Station 1, 62° 30' Lat. N., 8° 21’ Long. W., depth 132 fathoms; station 25, 63° 30’ Lat. N.,
54° 25’ Long. W., depth 582 fathoms; at Angmagsalik on the East coast of Greenland, depth 140 fathoms
(The Amdrup-Expedition r900); 61° 4o’ Lat. N., 7° 4o' Long. W., depth 135 fathoms (Ditlevsen); East of
the Far6de Islands, depth 250 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). The localities are
situated in the Davis Strait, at East-Greenland and at the Farée Islands.

5. H. mollis n. sp.
Pl. VI, Fig. 1.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules acanthostylu with a small
head, the larger slightly spined and smooth outwards, the smaller spined in the whole length, o-119—
0°53", not divided into two groups; the dermal spicules strongyla o:24—0°357""; microsclera chele

arcuate 0:027—0°'040”",

Most specimens of this species grow incrusting on Brachiopods, as well on living as on dead
specimens, one grows on a shell of a Buccimwm, one on a mussel-shell and finally one on an Oczdina.
The greatest extent measured is about 20"; the thickness generally does not exceed o-5™. Two speci-
mens grow in a remarkable manner; they are not attached to a definite substratum but grow on sand,
gravel and small particles of very different kinds, especially sponge-spicules; they then envelop the
substratum, so that the sponge together with the substratum forms irregular, wrinkled masses which
seem rather thick, but the real thickness is not greater than given above. The colour (in spirit) is
greyish brown. The swr/ace is smooth or nearly so. The dermal membrane is a thin film, but it is
for the greater part wanting on the specimens. Oscw/a and pores were not to be observed on account
of the bad condition of the dermal membrane.

The skeleton. The dermal skeleton; the skeleton formed of the dermal spicules is strongly

developed. Quite down at the base of the sponge the dermal spicules form fibres or fibre-like bands

48 PORIFERA. III.

running parallel with the underlayer; further there are bundles stretching obliquely up to the surface,
and at the surface there are again bundles or fibres present running more or less parallel with it;
besides, there are also found scattered spicules at the surface. The bundles are often rather thick.
The dermal spicules form thus the greatest part of the whole skeleton. The main skeleton consists of
acanthostyli with their head-ends on the substratum; they do not reach beyond the surface. Spongin
seems to be found at the base, but only to a very slight degree.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or
slightly curved and have a rather small head-swelling; the apex is even and long. The spinulation
is somewhat slight, as commonly the largest spines are found at the head-end; in the longer styli
the spines become very small outwards, and the outer part of the spicules is smooth; the smaller
styli are spined in the whole length, and the spines are generally larger. The styli vary much in
size, but they are not divided into two groups. The length is o119g—0'53™" and the diameter of the
head oor4—0027™". 2. The dermal spicules are strongyla, they are straight or, more rarely,
slightly curved, and they are slightly fusiform. The ends are not uniform, one end is rounded and
sometimes slightly swollen, the other end is thinner and rounded or with a stubby point. The length
is 0'24—0'357™" and the diameter about o7004—0'0057™". The strongyla may be slightly polytylote on
the middle part. b. Microsclera; these are chele arcuate; they have a curved shaft, the curvature
of which is distinctly situated in the middle of the shaft; the end-parts occupy nearly always less
than a third part of the length of the chela; the tooth is broadly elliptical, the ale are lobe-shaped,
of the same length as the tooth. The length may vary somewhat in the same individual and still
more in various individuals, it is in all 01027—o0°040™", and the diameter of the shaft is o70028—o'004™”.
The chele occur rather numerously in the dermal membrane, and they seem exclusively or at all
events chiefly confined to it. /

Locality: Station 25, 63° 30' Lat. N., 54° 25’ Long. W., depth 582 fathoms; station 28, 65° 14’ Lat. N.,
55° 42’ Long. W., depth 420 fathoms; station 83, 62°25’ Lat. N., 28° 30’ Long. W., depth 912 fathoms;
station 97, 65° 28’ Lat. N., 27° 39’ Long. W., depth 450 fathoms; further it has been taken at 64° 42’
Lat. N., 27° 43’ Long. W., depth 426 fathoms (Wandel), 62° 29’ Lat. N., 5° 17' Long. W., depth 160 fathoms
(Ad. Jensen, the cruise of “M. Sars” 1902) and 63°05' Lat. N., 20° 07’ Long. W., depth 295 fathoms (The
Fishery investigation steamer “Thor”). Nine specimens in all. The localities are situated in the
Davis Strait, the Denmark Strait, South of Iceland and West of the Faréde Islands.

6. H. curvichela n. sp.
Pl. VI, Fig. 2.

Incrusting; surface diffusely hispid. The main skeleton not dense. Spicula: megasclera, the
skeletal spicules acanthostyli with no distinct or only a slight head; the small spined in the whole length,
the larger less spined until only spined at the base; the styli divided into two groups, large 0'53—0 80",
small o'107—o0'30"™"; the dermal spicules strongyla, slightly polytylote, o.32—0'40”™; microsclera chele

arcuate, strongly curved, 0'031—0'037”".

Of the specimens of this species one grows on a stone together with 17. Koehleri, baculifera

PORIFERA. III. 49

Tops., dubia n. sp. (to be described hereafter), a Plocamia, an Eurypon and a Polymastia; another speci-
men is sitting on a Pecten-shell, likewise covered with several other species, a third specimen grows
on a Brachiopéd-shell and finally a fourth on an erect Bryozoon. The species forms incrustations of a
greatest extent of 25™" with a thickness of about o5™. The colour (in spirit) is white or whitish,
but with regard to two of the specimens it is stated, that they were deep blue in the living state.
The surface is diffusely hispid from rather long projecting spicules. The dermal membrane is a thin
and transparent film. ores and oscwda were not observed; some canals or canalicular cavities were
seen to shine through the membrane.

The skeleton. The dermal skeleton; in the dermal membrane there are numerous, but some-
what scattered chele. The dermal spicules form fibres or bundles stretching far down in the skeleton
and seen quite down at the base; they stretch in an oblique direction up to the dermal membrane,
and above, at the membrane the direction becomes nearly quite horizontal; some spicules are also lying
singly, quite horizontally in the membrane. Above, at the membrane the bundles are generally rather
strong with numerous spicules. The main skeleton is of the typical construction and consists of basal
acanthostyli with the head ends attached to the substratum, the longest styli pierce the dermal mem-
brane and project beyond it. The skeleton is distinguished by the fact that the styli stand somewhat
scattered, considerably more scattered than is commonly the case. At the base there is a distinct
amount of spongin, in which the heads of the styli are imbedded; the spongin seems to form a con-
tinuous lamella at the base of the sponge.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli which are straight or,
especially the larger ones, slightly curved; they have generally no distinct head marked off, or this
is only the case to a slight degree, but the dense spinulation at the base gives however the impression
of a swelling; they taper evenly into a somewhat fine apex. The spinulation is as usual, the spines
being largest at the head-end and radiating, while they are generally reclined on the shaft in the
smaller styles. The smallest styles are spined in the whole length, the longer the styles are, the
longer a part of the apex is smooth, in the longest styles only the lowermost part is spined, and the
spines are here generally small, nearly gritty, and not reclined. The size of the styles varies greatly,
the length from o'107 to about o80™™' and the diameter of the head is from oo18—o034™. To be
sure there is no principal difference between the styles, but there is a break in size between the
longest and those coming next in length, such that the longest do not go below 0'53™™ and the small
not beyond o730™™, 2. The dermal spicules are rather long, straight, slightly polytylote strongyla;
they have always one end thinner than the other; the length is 032—o40™", and the diameter in the
middle is about 0:005—0'007™". b. Microsclera; these are chele arcuate; they are distinguished by
the shaft being strongly, nearly semicircularly curved; there may in this respect be some difference,
the chele may be both more or less curved, but the typical form is near the semicircular curvature;
the end parts are relatively small, the tooth and the ale are short and rounded. The length is
0'03I—0'037™"; the shaft is somewhat flattened and about elliptical in section, its diameter is, as seen
from in front or from the side respectively oo05—oo10™. The chelz occur, as mentioned, numerously in
the dermal membrane, but, however, somewhat scattered; they were not observed otherwise in the body.

1) The greatest length cannot be given exactly, as these styles generally have the apex broken.
The Ingolf-Expedition. VI. 3. rp

50 PORIFERA. IIL.

This chela bears, in its mostly curved forms, strange to say, great resemblance to the chela

found in a species standing rather remote, viz. the chela figured by Carter (Ann. Mag. Nat. Hist. 5,

XV, PL IV, figs. 3¢, £). Carter figures also a developmental stage (d), but considers this as an “ill-
developed” spiculum.

Locality: Station 15, 66° 18’ Lat. N., 25° 29’ Long. W., depth 330 fathoms (bottom temperature
+0°75C.); station 89, 64° 45’ Lat. N., 27° 20' Long. W., depth 310 fathoms; both these localities lie in
the Denmark Strait; further it was taken East of the Farée Islands, depth about 250 fathoms, and
West of the Farée Islands, depth 160 fathoms, (Ad. Jensen, the cruise of “M. Sars” 1902). Four speci-
mens in all. It is curious that one of the localities, station 15, shows a negative bottom temperature,
while the other localities are positive, but it is to be remarked, that this station lies just at the border

between the cold and the warm areas.

7. H. rugosa n. sp.
Pl. III, Fig. 1, Pl. VI, Fig. 3.

Incrusting ; surface somewhat wrinkled, smooth; oscula present as very low cones, with a dense
skeleton of dermal spicules in the wall. Spicula: megasclera; the skeletal spicules acanthostyli with a
slight head, spined in the whole length, divided into two groups, large o-30—0'429"™", small o-15—o'19"™;
the dermal spicules polytylote strongyla o31—o 417"; microsclera large chele arcuate with the ends a

little recurved, 0-052—0°064”™.

Of this species we have two specimens, one growing on a Brachiopod-shell, the other on a
worm-tube. The sponge forms thin incrustations, which reach a greatest extent of 17™", with a thickness
not exceeding o5™". The colour (in spirit) is yellow or light brownish. The sazface is strongly
wrinkled and rugose, the dermal membrane being folded, thus giving rise to the formation of irregular,
sinuous furrows; this appearance is probably owing to contraction; for the rest the surface is smooth
without projecting spicules. The dermal membrane is a somewhat solid, easily separable membrane,
richly crowded with chele. On one of the specimens two oscuda are seen; these have a structure
similar to that of the oscula in H. Koehleri, they show in the centre a circular or oval impression,
around which the dermal membrane forms stellately radiating folds; the dermal spicules form here a
special skeleton, lying close together in the oscular wall with one end towards the opening, and from
this radiating out in the membrane. The diameter of that part of the membrane which may be
termed osculum is 1'5—2™". Pores were not to be seen in the membrane which is so densely charged
with chele.

The skeleton. The dermal skeleton; the dermal skeleton proper is formed of the chelze which
are extremely close-lying in the membrane; when they are so close-lying, this is perhaps due to
contraction. The dermal spicules partly contribute to the formation of the other skeleton of the
sponge, as they form bundles or fibres, stretching from the very base up to the dermal membrane,
generally in a very oblique direction; in many places they also form horizontal fibres just below the
membrane; finally they form, as mentioned, the skeleton in the oscular wall. The fibres and bundles

formed of the dermal spicules are rather thick. The main skeleton is of the typical construction, and

Se ee ee a ae ae

PORIFERA. IIL 51

consists of vertical acanthostyli with their heads based on the substratum; the longest of them reach
the dermal membrane, but do not pierce it. Just at the base of the sponge there is, I believe, a
slight amount of spongin, but I was not able to see it with absolute certainty.

Spicula: a. Megasclera; 1. The skeletal spicules are straight or slightly curved acanthostyli;
they have a slightly swollen head and taper evenly into a long apex which outermost is a little more
abruptly pointed. The spines on the head are large, they are not pointed but truncate and not rarely
somewhat hook-shaped. The spines on the shaft are somewhat dense and continue out to the point,
but they are more scattered in the outermost part; the spines are reclined and compressed, so that
they get the shape of a tooth of a saw. The styli vary greatly in size, and as intermediate forms
are very scarce they are divided into two groups, which are, however, not quite sharply limited.
The length lies in all between 015 and 0429™", and the diameter of the head is o1025—o040™™. When
the single intermediate sizes are not considered the two sizes will be about o15—o1g™ and o30—
0429". 2..The dermal spicules are slender, straight, or more rarely slightly curved, polytylote
strongyla, the ends are generally slightly swollen, so that the spicules approach to subtylota; one end
is as a rule a little thicker than the other, and the thinner end has the largest swelling; the swellings
are the more distinct the thinner the spicule is, in the thickest strongyla they are very slight or quite
wanting. The strongyla vary somewhat in size, the length is between 031 and o417™", and the
diameter is o7005—o'008™. b. Microsclera are chele arcuate; they have a curved shaft and the
ends are somewhat recurved; the tooth is lanceolate, with a long tuberculum, and the alz are of the
same length as the tooth; the shaft is somewhat flat, and nearly always slightly dilated in the middle.
The chela is rather large, and the size is somewhat constant, the length is 0:052—0064™", and the
diameter of the shaft varies from about oo05—oo11™ in relation to the chela being seen in front or
in side view, and to the dilatation in the middle of the shaft being larger or smaller. Single develop-
mental stages were seen. The chele occur, as said, in enormous numbers and densely crowded in
the dermal membrane, and they do not seem to occur otherwise in the body of the sponge.

Locality: Station 9, 64° 18' Lat. N., 27° 00! sere W., depth 295 fathoms. Two specimens. The
locality lies in the Denmark Strait.

8. H. splenium n. sp.
Pl. VI, Fig. 4.
Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules densely and entirely
spined acanthostyli with a very slightly marked head, divided into two groups, large o:23—027"", small

oog—o'12"™; the dermal spicules strongyla o-25—0-31"" ; microsclera chele arcuate 0:041—0o 047".

This species grows as rather extended incrustations on a somewhat large stone; it has a
greatest extent of about 16™", the thickness is small, below o5™", The colour (in spirit) is whitish
grey. The surface is dispersedly hispid from projecting skeletal styles, and it seems to be so also when
the dermal membrane is undamaged. The dermal membrane is a thin film, resting on the skeleton
below. Here and there larger and smaller openings for the canal system were observed, partly placed
in groups; they are probably both fores and oscula,

7

52 PORIFERA, III.

The skeleton. The dermal skeleton; the dermal spicules form partly bundles, partly they are
also seen lying scattered; they lie horizontally or stretch obliquely upwards between the ends of the
skeletal styli, without any regularity; they lie horizontally especially just below the dermal membrane,
and when the sponge is viewed from above, the spicules are seen lying irregularly below the membrane.
The main skeleton consists of vertical, somewhat densely placed acanthostyli, the longest of which
project beyond the surface. At the base a slight amount of spongin is found.

Spicula: a. Megasclera. 1. The skeletal spicules are straight acanthostyli; the head-end is
only pronounced to a very slight degree, and the styli are therefore somewhat club-shaped. The
spinulation is dense and is both in the small and the large forms continued quite to the point, or the
spines are at most a little more dispersed towards the point; the spines are directed downwards; they
are distinct but not large. The length of the styli is oog—o27™" and the diameter of the head
oo15—o024™. Though the styli do not vary much in length in all, they are divided however into two
groups, the larger ones not going below 023™ and the small not beyond o1r2™, 2. The dermal
spicules are straight strongyla, they are always a little thicker at one end than at the other, but
they are otherwise of the same thickness in the whole length; sometimes they are very slightly poly-
tylote. The length is o25—o31™ and the diameter o1005—01007™. b. Microsclera; these are chele
arcuate; they are of ordinary shape, the shaft is evenly curved, the tooth elliptical, the alze lobe-
shaped and broadly cut below. The length is o041—o047™ and the diameter of the shaft is o1003—
o7004™". The chelze occur numerously in the dermal membrane, but not, however, forming a layer.

This species is somewhat related to H. storea, but it is characterised by the styli being more
densely spined, and spined to the very point, and the spines are smaller; besides, the styli are divided
into two groups; the chele are of another}shape, and finally also the dermal spicules show a difference.

Locality: Station 125, 68° 08' Lat. N., 16° 02' Long. W., depth 729 fathoms (bottom temperature
+ 0°8C); the locality lies North of Iceland.

g. H. tenuicula n. sp.
Pl. VI, Fig. 5.
Incrusting; surface somewhat hispid. Spicula: megasclera; the skeletal spicules acanthostyli with
a slightly swollen head and divided into two groups, large, with the apical part slightly spined or smooth,
0°286—o'47"™, small, spined in the whole length, o12—o15”"; dermal spicules strongyla 0:238—o0'31"™;

microsclera chele arcuate 0032—0'037"™.

Of this species we have four specimens growing as thin incrustations on a Hamacantha impli-
cans, on a Brachiopod-shell, on a tube of Placostegus tridentatus and finally on a stone, bearing a
specimen of Petrosia crassa; the largest specimen grows on the Brachiopod-shell, and it reaches the
same extent as this, viz. 25™™, but for the rest it grows on both sides of the shell which it thus quite
covers. The sponge is very thin, scarcely reaching more than 0'25™™ in thickness; this is, as will be
seen below, less than the length of the largest styli, which consequently project beyond the surface,
The colour (in spirit) is slightly yellowish. The swrface is distinctly hispid on account of the projecting
of the longest styli. The dermal membrane may be traced as a thin film, supported by the dermal

spicules. Pores and oscula were not to be seen.

PORIFERA. III. 53

The skeleton. The dermal skeleton consists partly of bundles of dermal spicules which stretch
up to the membrane from the skeleton below, partly and chiefly of spicules lying horizontally in the
membrane; the latter spicules are partly scattered, partly collected into bundles or short fibres. The
main skeleton is formed of vertical acanthostyli, the shorter of which reach to the surface, while the
longer project through it. At the base of the acanthostyli there is found an amount of spongin, but
it is difficult to observe.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli, they have the head-end
slightly swollen and taper from here into a long apex. The styli are divided into two sizes which
are to be sure not connected by transitional forms, but do not show, however, any principal difference
in shape. The larger styli are straight or slightly curved; they have a densely spined head, the
spines are here not pointed, but truncate or irregularly cut at the apex; on the lower part of the
shaft the spines are still somewhat dense, but they are small, outwards they become more scattered,
and the outermost part is smooth or has only some single spines; the spines on the shaft are reclined.
The small styli are likewise straight or very slightly curved, they are spined in the whole length,
and the spines are reclined; the head is most densely spined. The length of the large styli is 0-286—
0'47™" with a diameter at the head of 0028™"; the greatest length is only rarely seen; the small styli
are o'12—o0'15™" long and o7020™ thick at the head. 2. The dermal spicules are straight strongyla,
one end is a little thinner than the other, and this thinner end is often slightly swollen; the length
is 0'238—o731™" and the diameter about o004™. b. Aficrosclera; these are chele arcuate; they
have an evenly curved shaft, an elliptical tooth and lobe-shaped ale of the same length as the tooth;
the free middle part of the shaft is not much more than the third part of the total length of the
chelz. The length is 0032—0037™", aud the diameter of the shaft is about oo04™". The chele are
found in the dermal membrane, generally they are scattered, sometimes lying more densely.

This species is distingushed from H. storea by its more slightly spinulous acanthostyli which
are divided into two groups, and by a different shape of the chelz.

Locality: Station 1, 62° 30' Lat. N., 8° 21' Long. W., depth 132 fathoms; station 35, 65° 16’ Lat. N.,
55° 05’ Long. W., depth 362 fathoms; station 98, 65° 38’ Lat. N., 26° 27’ Long. W., depth 138 fathoms; and
East of the Farée Islands, depth 250 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). The localities
are situated in the Davis Strait, the Denmark Strait and East and West of the Fardée Islands.

10. H. similis n. sp.
Pl. VI, Fig. 6.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules acanthostyli with a small
but distinct head, the spinulation slight, the larger styli smooth in a long apical part, the styli divided
into two groups, large o-41—o'65"™, small o-149—0'238"" ; the dermal spicules strongyla o'298— 0°35” ;
microsclera strongly curved chele arcuate 0:035—0'044"™.

This species forms small incrustations on shells of Brachiopods, mussels and Gasteropods, and
on small stones; one specimen grows on a dead Oculina and another on a specimen of Jotrochota

54 PORIFERA. III.

oxeata; the greatest extent to which it reaches is 16™™. The colour (in spirit) is whitish to light
yellowish. The szrface seems, in the places where the sponge is undamaged, to be without projecting
spicules. The dermal membrane is a thin film with close-lying chele. .

The skeleton. The dermal skeleton; the dermal spicules form fibres or bundles, which under

various arrangements stretch more or less obliquely from the interior of the sponge out to the dermis;

they may also be found in or below the membrane as horizontal bundles; the fibres may be of a

considerable thickness; besides, the membrane has close-lying chele. The main skeleton consists in
the ordinary way of more or less vertical acanthostyli with their heads attached to the substratum;
the styli are placed somewhat dispersedly. Spongin was not observed.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli with a more or less
marked, but small head and they taper into a long, fine apex; they are curved, and the curvature
lies nearest to the head, it is found both in the large and small styli, for which latter it is
especially characteristic. The spinulation is not strong; in the longer styli there are larger spines
only on the head-end, the lower part of the shaft is grittily spinulous and the larger outer part,
sometimes the whole shaft, is smooth; the smaller styli are a little more strongly spined and in the
whole or nearly the whole length. The length is in all o149—065™"; the styli are rather distinctly
divided into two groups, the large not going below o41™ and the small not beyond 0238™™; the
diameter of the head is oo14—o025™". 2. The dermal spicules are straight strongyla, they are only
very slightly thicker in the middle than towards the ends, one end is a little thicker than the other.
The length is o-298—o0'35™" and the diameter is between o004 and o1005"". b. Microsclera; these
are chele arcuate; they have an evenly but strongly, up to nearly semicircularly curved shaft, the
end-parts are relatively small, the ale lobe-shaped; the shaft is somewhat flattened. The length is
0°035—0'044™", and the diameter of the shaft o004—oo11™ according as it is seen in profile or
in front view. The chele occur numerously in the dermal membrane and sparingly otherwise in
the tissue.

This species stands near to //. longistylus n. sp. (to be described hereafter), but it is distingushed
by the more strongly curved small styli and by other dermal spicules and chelz; it is also related to
H. curvichela, but also from this it is distinguished by the characteristic, curved small styli. The
species must moreover be allied to H. (Hymeniacidon) paupertas Bow. but the small styli figured for
this species, and also the figure of the chele seem to prevent identification.

Locality: Station 1, 62° 30’ Lat. N., 8° 21' Long. W., depth 132 fathoms; station 9, 64° 18’ Lat. N.,
27° oo' Long. W., depth 295 fathoms; station 10, 64° 24' Lat. N., 28°50’ Long. W., depth 788 fathoms;
station 54, 63° 08’ Lat. N., 15° 4o' Long. W., depth 691 fathoms; station 85, 63° 21’ Lat. N., 25° 21’ Long. W.,

depth 170 fathoms; station 89, 64° 45’ Lat. N., 27° 20' Long. W., depth 310 fathoms; station 94, 64°56’ —

Lat. N., 36° 19’ Long. W., depth 204 fathoms; station 98, 65° 38’ Lat.N., 26°27’ Long. W., depth 138
fathoms; further it has been taken at 63° 12’ Lat. N., 20° 06’ Long. W., depth 270 fathoms (The Fishery
investigation steamer “Thor”); and East of the Farée Islands, depth 250 fathoms (Ad. Jensen, the cruise
of “M. Sars” 1902); in all about nine specimens. The localities lie in the Denmark Strait, South of
Iceland and East of the Farée Islands,

ee re

ee"

PORIFERA. Iil. 55

fro dH: nummulus nl. Sp.
Pl. WII, Fig. 11, Pl. VI, Fig. 7.

Incrusting ; surface hispid? Spicula: megasclera; the skeletal spicules acanthostyli with no real
head, divided into two groups, large, only spined below, 0'51—0'95”", small, entirely spined, 0-12—0'14”" ;
the dermal spicules strongyla, somewhat tending towards tornota, 0:35—0'46"™" ; microsclera chele arcuate,

strongly curved with the ends somewhat recurved, o-028—o054”™.

Two specimens of this species grow as small incrustations on stones, both of which are richly
overgrown with several other sponges, a third specimen coats the broken base of a Hornera sitting
on a stone. The greatest extent reached is only 1o™™. The colour (in spirit) is white. Beyond the
surface project the long styli, but whether this is so in the undamaged sponge I cannot say, as the
surface is in nearly all places not intact. The dermal membrane is a thin film and seems to have no
proper skeleton, but it is for the greater part wanting. Oscwla and pores were not observed.

The skeleton. The dermal skeleton; the dermal spicules form bundles stretching more or less
obliquely from the lower part of the sponge to the dermal membrane; the bundles are often rather
thick. The main skeleton consists in the ordinary way of acanthostyli with their heads placed on the
substratum; the long styli reach through the whole sponge; the small styli are by far the most
numerous, so that each of the large styli is placed in a group of small ones. Spongin is found at
the base of the styli.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are divided into
two very distinct groups, large and small; the large styli have the base a little thickened but not
forming a real head, from here the style tapers evenly to the point; the base bears distinct, but not
large spines, outwards they soon nearly disappear so that about the lower half part is only slightly
gritty, the rest is smooth; the styli are generally somewhat curved near the base. The small styli
also have the head but little pronounced, but it is beset with somewhat large spines, and for the rest
the style is spined in its whole length, with somewhat reclined spines. The length of the large styli
is O51—095™" with a thickness at the base of 0'035—o040™, the small styli are o12—o'14™ long
and at the base about oo2r1™™" thick. 2. The dermal spicules are strongyla with some tendency
towards tornota; they are straight and generally one end is a little more pointed than the other; they
are of the same thickness in the whole length; their length is 035—046™, and the diameter o005 —
0008". Microsclera are chele arcuate; they have a strongly curved shaft, with the end-parts
somewhat recurved, the ale are lobe-shaped and the tooth elliptical; the chele vary somewhat in
size, the length is o7028—o054™" and the diameter of the shaft is o004—o006™. The mentioned
recurvation of the end-parts is very slight or quite disappears in the smallest chelz.

This species bears some resemblance in spiculation to H. rugosa, but it has larger and much
smoother styli, smaller chele of a different shape, and the strongyla are not polytylote; it is also
allied to 77. stylata n. sp. (to be described hereafter), but differs by the longer and thicker acanthostyli,
and a different shape of the chele which in s¢yla¢a have the end-parts not recurved.

Locality: Station 85, 63° 21’ Lat. N., 25° 21' Long. W., depth 170 fathoms; station 89, 64° 45’
Lat. N., 27° 20’ Long. W., depth 310 fathoms; and at 65° 50’ Lat. N., 26° 53' Long. W., depth

56 PORIFERA. III.

208 fathoms (The Fishery investigation steamer “Thor”). The localities are in the Den-
mark Strait.

12. H. dubia n. sp.
Pl. VI, Fig. 8.

Incrusting; surface finely hispid. Spicula: megasclera; the skeletal spicules acanthostyli with a
small head, divided into two groups, large, only spined below, o-34—0.38"™", small, entirely spined,

or0o—o'23"™"; the dermal spicules strongyla o-26—o.32"™"; microsclera chele arcuate 0:040—0-051"™,

Of this species we have a specimen growing on a stone together with specimens of 17. Koehleri,
baculifera Tops. curvichela, Eurypon sp. and Plocamia sp. The specimen has a greatest extent of only
ro™", and it is very thin. The colour (in spirit) is whitish. The swzface is finely hispid. The derma:
membrane is thin, somewhat richly charged with chele. Oscuda and pores were not observed.

The skeleton, The dermal skeleton consists of bundles of dermal spicules, stretching obliquely
from the skeleton below up to the surface; the bundles may vary with regard to the number of spi-
cules contained, but it is generally not great. The main skeleton is constructed in the typical way
and consists of erect acanthostyli with their heads based on the substratum, the longest of them reach
to the dermal membrane, and it would seem that they penetrate through it. Spongin seems to be
present at the base, but to a very slight degree.

Spicula: a, Megasclera. 1. The skeletal spicules are acanthostyli; they are divided into
two rather well separated groups; the larger styli are straight, or most frequently slightly curved, they
have a small head-swelling and they taper evenly out into a long apex; on the head-swelling there
are somewhat large spines, but for the rest the styli are nearly smooth, only on the lower part, near
the swelling, they are slightly gritty; the small styli are similarly shaped, but they are straight, the
shaft is totally spined, but the spines are sometimes somewhat dispersed. The length of the large
styli is 034—0'38"™" and the thickness at the base 0035"; the length of the small styli is o10—o-33™
with a thickness at the base of o102—0'028"", the greatest of these sizes, which form transitions to
the large styli, are of rare occurrence. 2. The dermal spicules are strongyla; they are straight and
cylindrical, not thicker in the middle; their shape is in so far characteristic as they grow evenly
thinner from one end to the other, so that one end is always distinctly thicker than the other. The
length is o'26—o32™", and the diameter in the middle about o005"". b. Microsclera are chele
arcuate; they have an evenly curved shaft, the ale are lobe-shaped, slightly triangular and the
tooth elliptical with a long, narrow tuberculum; generally the teeth have such a direction that they
lie in a straight line connecting the two ends of the chela; the most characteristic feature in the
chela is, that the shaft is flattened to a high degree and in such a way, that the front side is nearly ~
flat, the hinder side on the other hand somewhat rounded. The length of the chela is 0'040—0'051™",
the thickness of the shaft is 01003™" and its breadth oo11™™. The chelz occur abundantly and some-
what close-lying in the dermal membrane.

The species is related to H. Koehleri, but is distinguished by the large styli, which are nearly
smooth and by the strongyla being not polytylote; it is also related to H. mummulus, but from this
it is distinguished by the chelz with the flattened shaft and not recurved end-parts.

PORIFERA. III. 57

Locality: East of the Farée Islands, depth 250 fathoms (Ad. Jensen, the cruise of “M.
Sars” 1902).

13. H. stylata n. sp.
Pl. III, Fig. 2, Pl. VI, Fig. 9.

Incrusting, of a thickness up to 2”; surface smooth, with some small, conical papille, bearing
oscula (and pores), and with a dense skeleton of dermal spicules in the wall. The dermal skeleton
strongly developed, the main skeleton weak. Spicula: megasclera; the skeletal spicules acanthostyli with
a small, or nearly no head, divided into two groups: large, only spined below, and with the apex short
pointed, a35—063"™"; small, entirely spined, longer pointed, o13—0178""; the dermal spicules long

strongyla 0-35—0'52™”"; microsclera chele arcuate o:038—o050””.

This species grows exclusively on loose bottom material as gravel, sand and the like; it may
then sometimes grow all round the material and quite imbed it, so that the substratum in this case
comes to lie in the interior of the sponge; this manner of growing recalls to some degree that of
Hamacantha implicans described in the first part of this work. The thickness of the incrustation
varies a good deal on account of the manner of growing, from o'5 to about 2™"; moreover parts of
the sponge-tissue may reach in between the particles of the substratum. The specimens in hand form,
together with their more or less imbedded substratum, roundish or elongate bodies of a greatest length
of 14™™ and a thickness of 4—~5™™. The colour (in spirit) is whitish or yellowish grey. The surface
bears some conical papillae, which are generally more or less depressed; they may reach a length of
2™m, The surface is otherwise smooth or at all events only slightly hispid from projecting dermal
spicules. The dermal membrane is somewhat solid and not specially thin; it is densely filled with
chelz and rests on the skeleton below, but it has no proper skeleton. Oscula and pores: The above-
mentioned papillze bear the oscula, and I think also the pores; I have not observed pores, but there
seems to be some difference between the papille, some being higher and with a distinct opening,
others being lower, and, as it were, closed at the apex; the latter perhaps are pore-bearing, the case
being as in the following species, H. verrucosa.

The skeleton is on account of the mode of growth of the sponge, irregular, especially in
the deeper parts. The dermal skeleton: the skeleton formed of the dermal spicules is by far the most
predominant, the other skeleton being only weakly developed. The dermal spicules form bundles or
fibres stretching from the substratum and occupying nearly all the thickness of the sponge; they are
somewhat irregularly arranged, but at the surface they form distinct fibres, running somewhat hori-
zontally under the dermal membrane, but reaching it with the ends which have the spicules spread in
a penicillate way and bear the membrane. Fibres from the skeleton stretch up in the wall of the
papillz and form here a layer of parallel and densely arranged spicules. The dermal membrane is
moreover filled with chelz. In the parts of the sponge found between the particles of the sub-
stratum, dermal spicules are also seen. The main skeleton is as said rather feeble in proportion to the
whole skeleton; it is formed in the ordinary way and consists of acanthostyli with the heads inserted
on the substratum, but the acanthostyli are rather scattered; they are turned in very different directions,

and they are found in greatest numbers in the parts of the sponge which are distributed between the
The Ingolf-Expedition. VI. 3. 8

58 PORIFERA. III

particles of the substratum; the spicules situgted here may be directed in any direction. At the sub-
stratum there is a small amount of spongin.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli which are divided into two
groups, large and small; the large styli are rather long and slender, they are straight or slightly and evenly
curved; the head is weakly or not at all developed; they taper only a little outwards, and they are short and
abruptly pointed. The spinulation is only present in the lower part of the style, at most stretching
half the way out, but very dispersed in the outer part; the spines are somewhat robust, generally
there are some larger spines among them, especially at or near the base, thus marking the otherwise
weakly marked head. The small styli do not reach more than one fourth in length of the large, they
are straight and longer pointed than the large; their spinulation resembles that on the base of the
large, but they are spined in their whole length. The large styli are 0o35—063™" long, and the
diameter at the base is o7o20—0028™", The small styli are of a length of o13—0'178™™ and a diameter
at the base of about oor4™™. No intermediate forms between the two sizes of the styli are found.
2. The dermal spicules are long and straight strongyla; one end is generally a little thinner than
the other, but otherwise they are nearly of the same thickness throughout their whole length. The
length is 0735—0'52™" and the diameter o'7006—o'008™. b. Microsclera. These are chele arcuate,
they have an evenly curved shaft, the ale are strongly incised in the lower edge, and hence somewhat
claw-shaped when viewed laterally, the tooth is pointed lanceolate. The length of the chelz is
0038 - oo50™"; the shaft is somewhat flat, the thickness is in relation to this ooo4—o007™. The
chele are seen in small numbers through the whole sponge and densely filling the dermal membrane.

This species is somewhat related to H. nummulus, but it is, as mentioned under this species,
distinguished by smaller acanthostyli and a different shape of the chele.

Locality: Station 113, 69° 31’ Lat. N., 7° 06’ Long. W., between Iceland and Jan Mayen, depth

1309 fathoms (bottom temperature + 1°0C.); about ten specimens.

14. H. verrucosa n. sp.
Pl. III, Fig. 3. Pl. VII, Fig. 1.

Incrusting ; thickness about 2”; surface smooth, covered with wart-shaped papille with a dense
skeleton of dermal spicules in the wall, bearing oscula (and pores). Dermal skeleton strongly developed,
the main skeleton weak. Spicula: megasclera; the skeletal spicules acanthostyli with a generally small
head, the longer only spined below, the smaller spined in the whole length, o'095—0'62"", not divided

into two groups; the dermal spicules long strongyla o.37—0'52"" ; microsclera chele arcuate 0035—0'044"™.

Of this species we have four specimens, one has grown as an incrustation on a stone from which
it has been peeled, in the basal part of it much gravel and the like is imbedded; the specimen is
now separated into two pieces of a largest extent of about 25™, but they have certainly formed a
single incrustation. Of the other specimens one forms an incrustation on a basalt-block, it has a
greatest extent of 22™; two others cover Asfarte-shells and are of similar dimensions. The thickness
is about 2™. The colour is in the present state (in spirit) greenish white, but for one of the speci-
mens it is stated to have been deep blue in the fresh state of the sponge. The szr/ace is smooth,

eS ee Pee hee ree es

PORIFERA. III. 59

without projecting spicules, but it is densely beset with low wart-shaped papilla, which may vary
somewhat in height and therefore be more or less conspicuous. The dermal membrane is a thin, but
somewhat solid membrane; it is densely charged with chele. Oscula and pores: The mentioned
papillz are, I suppose, both oscular and pore-papille, the fact is that there seems to be some difference
in their structure; some of them are relatively pointed and have an opening above, while most of
them are broader above and have here a prominent edge, but inside this are closed by a membrane;
in this membrane I have not observed pores, but probably they are closed; in both cases there are
large, hollow spaces below the papille.

The skeleton. The dermal skeleton; as the skeleton formed of the acanthostyli is quite in-
considerable, it is the skeleton consisting of the dermal spicules which forms by far the greatest part
of the whole skeleton; it consists of fibres which stretch quite from the base of the sponge upwards
and support the dermal membrane; the fibres run more or less vertical, outermost, at the surface, the
spicules are somewhat penicillately spread, or the fibres bend off below the membrane and run
under it as horizontal fibres. The fibres may have a rather variable thickness, but they are always
relatively thick and consist of many spicules; the thickness was e. g. measured to o06—0'24™".
Under their course outwards the fibres may be more or less branched. In the wall of the papille
the dermal spicules form a dense skeleton, lying parallel with one end towards the edge of the
papilla and here they are somewhat projecting. The dermal membrane itself is densely charged
with chelz, forming a dense layer. The main skeleton consists as commonly of acanthostyli with
their head-ends attached to the substratum; the skeleton is much dispersed as there is only found a
bundle of styles in each place where the fibres, formed of the dermal spicules, go down to the sub-
stratum, the styli thus forming the lowermost part of these fibres, just at the substratum. At the
base a somewhat rich amount of spongin is found, in which the heads of the acanthostyli are imbedded.

_ Spicula: a. Megasclera, 1. The skeletal spicules are straight or, especially the larger ones,
slightly curved acanthostyli; they taper into a long apex, which in the larger of them is a little more
abruptly pointed outermost. The head may be somewhat various, it is generally not much swollen, but
however somewhat pronounced on account of its spinulation. The spines are largest on the head; the
larger styli are only spined below, when they are shorter the spinulation goes further out, and the
smallest styli are entirely spined; in these latter the spines are rather large and they are reclined, in
the larger styli the spines are most often smaller and less distinctly reclined. The length varies much,
from o095—062™", and the diameter of the head from o:7014—o'039™". All transitions in size are found,
but the intermediate sizes are rare. 2. The dermal spicules are long, straight or very slightly
curved strongyla which are of the same or about the same thickness in the whole length; one end
is short and rounded, the other is a little longer, nearly truncately pointed, this latter end is generally
slightly swollen, not so much however that the spicule may be termed a tylostrongyle; the swollen
end corresponds to the original end of the spicule; sometimes both ends may be very slightly swollen,
the spicule thus approaching a tylote; the strongyla may be quite slightly polytylote. The length is
0'37—0'52™" and the diameter about o004—o008"™". Quite monactinal developmental stages were
found. b. Microsclera; these are chele arcuate, they are of ordinary shape, with a regularly and

evenly curved shaft, the tooth is elliptical and the ale lobe-shaped, short and rounded, and of the
8*

60 PORIFERA. III.

same length as the tooth. The length is 0035—0044™", the shaft is flattened, its thickness is in

relation to this o1003—0007"". The chelz occur through the whole sponge and in a dense layer in

the dermal membrane.

This species is somewhat characteristic, besides from its exterior, from the small acanthostyli
being straight and slender and with large, distinctly reclined spines, and from the large strongyla; it is
to be noted that it is not the smallest styli, but those a little longer which especially have large
spines. The species is nearly related to the preceding 7. stylata, but it is distinguished by the small
acanthostyli with their large, reclined spines and distinct heads; also the strongyla are different, and
the alz of the chele are longer and more pointed in H. stylata.

Locality: Station 54, 63° 08' Lat. N., 15° 40o' Long. W., depth 691 fathoms; and at 64° 42’ Lat. N.,
27° 43’ Long. W., depth 426 fathoms (Wandel). In all four specimens. The localities lie in the Den-
mark Strait and south of Iceland.

15. H. procumbens n. sp.
Pl. VII, Fig. 2.

Incrusting; surface slightly hispid. Spicula: megasclera; the skeletal spicules acanthostyli with
a small head, spined in the whole or nearly the whole length, the longer only very slightly spined out-
wards, o-089—o'35"", not divided into two distinct groups; the dermal spicules tornota o23—0:327"";

microsclera chele arcuate, often strongly curved, o0'024—0'038™™.

This species grows as small incrustations on pebbles, one specimen grows on the shell of
an Arca, and one on a dead Oculina; it has a greatest extent of about 12™™, and the thickness
is exceedingly small. The colour (in spirit) is nearest whitish or whitish grey. The szr/ace is
very slightly hispid on account of the generally only to a slight degree projecting spicules. The
dermal membrane is a thin film, supported by bundles of dermal spicules; it has somewhat densely
lying chele.

The skeleton. The dermal skeleton consists of bundles of dermal spicules which are generally
somewhat fan-like spread; the bundles stretch out to the surface, but they are for the greatest part
strongly decumbent in the membrane. The main skeleton has the typical construction; it is rather
dispersed, the single styli standing somewhat scattered. Spongin I could not observe.

Spicula: a. Megasclera. 1. The skeletal spicules are straight or nearly straight acanthostyli
with the head-end most frequently rather weakly marked; the longest styli are often somewhat curved
near the base; the spines are large on the head-end, but decrease rapidly outwards both with regard

to size and to number, and the largest styli have thus the spines on the outer part much dispersed,

and the spines are here weak. The small styli are entirely spined, and the spines are larger, but
there does not seem to be sharply divided groups. The length is oo89—0'35™™ and the diameter of
the head is oo11—0'027™". 2. The dermal spicules are tornota which are straight, or sometimes a
little irregularly curved; one end is generally slightly thinner than the other; they are fusiform, being
somewhat thicker in the middle, and some few are seen reaching a considerable thickness. The

length varies much, from 0:23—0'327™", and the diameter is o7004—00075™". b. A@icrosclera; these are

we eee a

PORIFERA. IIL : 61

chelz arcuate; they have a more or less, sometimes very strongly, curved shaft, the end-parts are
relatively small. The length is 0024—0038™", and the diameter of the shaft o003—o0005"". The
chelz occur numerously and rather densely in the dermal membrane.

This species may vary somewhat, especially with regard to the size and shape of the chele;
it is most characterised by the fusiform tornota, and this character in conjunction with the shape of
the acanthostyli distinguishes the species with certainty.

Locality: Station 54, 63° 08' Lat. N., 15° 40’ Long. W., depth 691 fathoms; station 98, 65° 38’ Lat. N.,
26° 27' Long. W., depth 138 fathoms. The localities are situated in the Denmark Strait and South
of Iceland.

16. H. perforata n. sp.
Pl. III, Fig. 4, Pl. VI, Fig. 3.

Incrusting; surface somewhat hispid; main skeleton rather dense. Spicula: megasclera; the
skeletal spicules acanthostyli with a very small or no head, entirely spined, or the longer with a smooth
apical part, vo80—0'53, not divided into two groups; the dermal spicules slender tornota 0178—o22™";

microsclera chele arcuate, very varying iM size, 0'02I—o0'054"™.

This species grows chiefly on Brachiopods, as well on dead shells as on living specimens;
we have in all sixteen specimens, thirteen of which grow on Brachiopods; the other three grow re-
spectively on a Bryozoon, a worm-tube and a Peeten-shell. The greatest extent to which the species
reaches is about 16™", and the thickness is not beyond o5™™. The colour (in spirit) is brownish
yellow to dark greyish brown. The szz/ace is hispid on account of the longer styli projecting beyond
it. The dermal membrane is a thin and transparent film. In the membrane larger and smaller,
circular or oval openings are found, which are oscuda and pores; they were measured of sizes from
about o05 to 0'3™", but there seem to be all intermediate sizes, so that it is often not possible to
decide whether we have to do with incurrent or excurrent openings; the smaller openings, however,
were most frequently collected in groups over the subdermal cavities, but the dermal membrane was
much damaged and therefore the whole structure was not to be decided with certainty; probably
there is the difference, that the pores form sieves while the oscula are larger, single openings. The
somewhat close-lying, circular subdermal cavities or openings of the canals shine through the mem-
brane, but they are only visible by the aid of a lens.

The skeleton. The dermal skeleton; in the dermal membrane occur the chele numerously, but
somewhat scattered. The dermal spicules form bundles which stretch in an oblique direction from
the skeleton out to the membrane; besides, both bundles and scattered spicules are found lying hori-
zontally in the membrane. The mazn skeleton consists in the ordinary way of acanthostyli which
have their heads attached to the substratum; the longest of the styli pierce the membrane, the surface
thus getting strongly hispid, but as the largest styli are not numerous, the sponge is somewhat
dispersedly hispid; on the other hand the styli are in this species very dense at the base, so that
whether the sponge is seen in a vertical section, or the surface of attachment is seen from below,

the styli are seen standing nearly head by head, only here and there divided by the cavities of the

62 PORIFERA. III.

canal system. At the base of the sponge there is found a somewhat rich amount of spongin in
which the heads of the styli are imbedded.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or
generally slightly curved; they have no head-swelling marked off or this is only weakly pronounced,
and they taper evenly into a long, rather fine apex, and accordingly they are of a more or less club-
like shape. The size varies to a high degree, and in relation to the size the spinulation also varies,
but separate groups of size do not exist. The smaller the styli are the relatively stronger they are
spined, and the spines are on the small styli continued out to the very point; the longer the styli,
the longer a part of the apex remains smooth; in the large styli also the close-standing, some-
what large spines on the head-end are relatively smaller than in the small styli, and the spines placed
on the shaft are very small. The spines are in this species only slightly, or not at all reclined. The
length varies from oo80—o'53™", and the diameter at the head is about oo11—o'031™. 2. The dermal
spicules are thin tornota; they are straight, of the same thickness in the whole length or quite
slightly thicker in the middle; the points are typical tornote points, short and bounded by straight
lines, and they are very sharply pointed. The fully developed tornota have the two points uniform
or nearly uniform. The length is o178—o-22™", and the diameter about o:0028—o0040™™. Db. Micro-
sclera are chele arcuate; they have an evenly curved shaft, an elliptical tooth with a long
tuberculum, and alz of the same length as the tooth. The size varies very much, the length from
or02I—o'054"™™" and the diameter of the shaft is in relation to the size o002—o007™. Some single
developmental stages were seen. The chelz occur numerously in the dermal membrane, and are also
seen singly lower down in the sponge.

Locality: Station 4, 64° 07' Lat. N., 11° 12' Long. W., depth 237 fathoms; station 6, 63° 43’ Lat. N.,
14° 34’ Long. W., depth 90 fathoms; station 9, 64°18’ Lat.N., 27°00’ Long. W., depth 295 fathoms;
station 16, 65° 43' Lat. N., 26° 58’ Long. W., depth 250 fathoms; station 27, 64° 54’ Lat. N., 55° 10' Long. W.,
depth 393 fathoms; station 28, 65° 14’ Lat. N., 55° 42’ Long. W., depth 420 fathoms; station 85, 63° 21'
Lat. N., 25° 21' Long. W., depth 170 fathoms; further, it has been taken at 63° 05' Lat. N., 22° 23’
Long. W., depth 115 fathoms and 63° 21' Lat. N., 16° 22' Long. W., depth 296 fathoms. The localities lie
in the Davis Strait, the Denmark Strait, South of Iceland and between Iceland and the Fardée Islands.

17. H. clavigera n. sp.
Pl. III, Fig. 8b, Pl. VII, Fig. 4.

Incrusting, thin; surface hispid. Spicula: megasclera; the skeletal spicules club-shaped acantho-
styli, divided into two groups, both entirely spined, large o:-25—0'298”™", small oog5—o'12”" ; the dermal

spicules tornota o-16—0'178"" ; microsclera chele arcuate o-041—0'052”™.

This species grows incrusting on a stone, which bears several other small sponges, and it
grows quite close to a specimen of 7/7, Bowerbanki n. sp. to be described hereafter; it has a greatest
extent of 12™, and it is exceedingly thin and delicate. It is of a whitish colour (in spirit). The
surface is very hispid on account of the erect styli being protruding. The dermal membrane is

imperceptible and not separable, but it appears to be a very delicate membrane, richly provided,

PORIFERA. III. 6 3

however, with chele. Oscwla and pores were not seen, but the sponge is perforated by close-standing,
vertical canals which shine through the dermal membrane and are seen on the surface as dark, round
points; it would seem that the oscula are simple openings in the membrane, and the pores lie
several together over the openings of the incurrent canals.

The skeleton. The dermal skeleton consists of dermal spicules stretching from the skeleton
below and out to the dermal membrane; it is very weakly developed and seems only to consist of
single spicules, not forming bundles, and the spicules are not numerous. The main skeleten is formed
in the ordinary way of erect acanthostyli with the head-ends based on the substratum, the longer of
them protrude far beyond the surface; a very faint amount of spongin is present at the base.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli, and they are rather
characteristic; though the basal end is the thickest part of the spicule there is however no head-
swelling developed at all; from the basal end the spicule becomes only slightly thinner outwards,
and the point is somewhat short; the spicule thus has a somewhat club-like shape; they are generally
slightly curved. The styli are divided into two well defined groups, large and small. The large styli
have a somewhat slight spinulation, only at the base there are some stronger, but however rather
small spines, they are blunt and generally curved somewhat upwards towards the apex of the style;
on the other part of the style the spines are small, but they are present to or near to the point, and
they are reclined. The small styli have quite the same shape as the large, only they are generally
not curved and the spines are relatively larger. The length of the large styli is o25—o298™, with
a thickness at the base of oo21™™, and of the small styli o1095—o12™ with a thickness of about
o°013™™; as is seen the two groups are fairly distinct in size, and the variation in each group is only
slight. 2. The dermal spicules are tornota; they are straight, rather thin and of equal thickness
in the whole length; the points are short and sharp; the length is o16—o178™", and the diameter
0'002™, b, Aficrosclera are chele arcuatz; they have an evenly curved shaft, the ale are lobe-
shaped with the lower edge broad and straightly cut off, and the tooth is elliptical. The length is
o04I—o0'052™™" and the thickness of the shaft ooo5—o‘0o7™. The chele are abundantly present in
the dermal membrane.

This species is nearly related to H. perforata, but it is distinguished by several characters; the
main skeleton is less dense, the acanthostyli not being so densely crowded, the two distinct groups of
acanthostyli are not present in ferfora/a, and the acanthostyli are in the present species much less
spined and in their whole length, while in Jerforata they are more strongly spined, but with the
apical part smooth; also in the shape of the tornota and the chele there are small differences, and
finally the sizes of the spicules are different.

Locality: The Denmark Strait, 65° 50’ Lat. N., 26° 53’ Long. W., depth 208 fathoms (The Fishery
investigation steamer “Thor”).

18. H. platychela n. sp.
Pl. VII, Fig. 5.
Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules acanthostyli with a small

head, somewhat strongly spined in the whole or nearly the whole length, o:13—0'45"", not divided into

64 PORIFERA. III.

two groups; the dermal spicules tornota o.327—0°53%" ; microsclera chele arcuate of a curious, broad

and flat shape, 0:032—0'035”™.

Of this species we have one specimen, growing on a shell-fragment of a Pecten; the specimen
grows on both sides of the shell having grown round the edge from one side to the other; the largest
extent of the specimen is 15™", and the thickness about o5™. The colour (in spirit) is brownish
yellow. The szrface is hispid from projecting dermal spicules. The dermal membrane is a thin film, but
it is wanting to a great extent on the specimen. Oscuda and pores were not observed.

The skeleton. The dermal skeleton; the dermal spicules form bundles or fibres which stretch
from the main skeleton, often from the lower part of this or quite from the base, in an oblique
direction up to the surface, and project beyond this, and it is thus chiefly these spicules which cause
the hispidity of the surface; outermost the spicules in the bundles are spread out somewhat fan-like.
When the sponge is examined from above with a good lens, therefore, the fan-like bundles of dermal
spicules are seen. In the membrane chelz are found, but they are very scattered. The main
skeleton is of the typical construction, consisting of vertical acanthostyli with their heads fixed on the
substratum; the longest of them project beyond the surface and contribute to the hispidity of the
sponge. At the base spongin is found, but only to a very slight degree.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or
somewhat curved; the head-end is a little swollen, and they taper evenly into a long, fine apex. The
spinulation is somewhat strong, the spines on the shaft are compressed and reclined downwards; the
spines on the head-swelling are considerably longer, they are not compressed, and radiate straight
out; these spines are truncate at the end and sometimes somewhat curved and hook-shaped, the small
and intermediate styli are spined in their whole length, the longest styli, on the contrary, have a
generally rather short part of the apex smooth. The styli vary much in size, but they are not divided
into groups. The length is o13—045™", and the diameter of the head oo18—0035"". 2. The dermal
spicules are long, straight tornota, they are slightly fusiform; the ends are short pointed, and the
points are bounded by straight or concave lines. The fully developed tornota have equal ends, but
the developmental stages are monactinal. The length is 0°327—0'53™", and the diameter in the middle
about 07005—o0'008™". b. Microsclera; these are chele arcuate; they are of a curious, short and
flat shape; the shaft is slightly curved, and is not flattened; the ale are broad and lobe-shaped, and
the tooth is rather broad and a little shorter than the ale. The angle between the axis and the tooth,
and the curvature of the alz are such, that a transverse section of the chela through alz and tooth
would form a transverse ellipse. For the rest the chelz are not rarely of a more or less irregular shape, and
some monstrosities are also found. The length of the chelz is 0032—0035™", and the diameter of the _
shaft about o7004™™. The chelz occur only in the dermis, but also here only in small numbers. -

Locality: Station 89, 64° 45' Lat. N., 27° 20’ Long. W., depth 310 fathoms; the station lies in the
Denmark Strait.

19. H. basispinosa n. sp.
Pl. III, Fig. 5, Pl. VII, Fig. 6.
Incrusting; surface smooth, bearing some small, conical oscular cones with a dense skeleton of

dermal spicules in the wall. Spicula: megasclera; the skeletal spicules acanthostyli with a small head,

PORIFERA. III. é 65

divided into two groups, large, only spined at the base, 0'-42—0'59”", small, entirely spined, 0:09—0°23"™" ;
the dermal spicules large tornota, o-32—0°50”"; macrosclera small chele arcuate, resembling palmate

chele, 0°025—o'030”™.

The only specimen of this species forms an incrustation on a shell of a Brachiopod; it has a
greatest extent of about 15™™; the thickness is 05™™ or a little more. The colour (in spirit) is dark
brownish. The surface is smooth or nearly so, without projecting spicules; it bears some conical
papille of a length of about 1™; in the present state of the sponge the papillae are lying down to-
wards the surface. The dermal membrane is thin, resting on the skeleton beneath and provided with
some spicules, more or less scattered or bundle-like collected. Oscaula and pores: the mentioned papillz
are oscular papille with the oscular opening at their apex; the fibres of dermal spicules continue into
the wall of the papillae and form here a dense skeleton of spicules lying parallel to the longitudinal
axis of the papilla; pores were not observed with certainty; some few, small openings in the dermal
membrane may perhaps be pores.

The skeleton. The dermal skeleton. The skeleton formed of the dermal spicules consists of
bundles or short fibres, which stretch from the lower part of the sponge up to the dermal membrane;
the fibres are for the greatest part more or less horizontal; some single spicules or bundles lie in the
membrane or just below it. The main skeleton is in the ordinary way constructed of perpendicular
acanthostyli with the heads against the substratum; they are not close-standing but somewhat
scattered. A very slight amount of spongin is present at the heads of the acanthostyli.

Spicula: a. Megasclera. 1. The-skeletal spicules are acanthostyli; they are straight or
slightly curved near the base, and long pointed; the head is more or less pronounced, but generally
only to a slight degree. The longer styli are only spined at the base, on the head and a little way
out; the small styli are entirely spined, but the spines become scattered towards the point; the spines
are small, only at the base some few spines a little larger may be found. The styli are divided into
two distinctly separated groups, large and small; the large has a length of o'42—o59™™ and a diameter
of the head of o021—o025™™; the small styli are oog—o'23™ long, and the diameter of the head is
o'014—or02t™, 2. The dermal spicules are rather large tornota, they are straight or nearly so,
slightly tapering towards the ends and sometimes slightly polytylote; the points are short and sharp,
sometimes the ends are a little swollen; the length is o32—o'50™ and the diameter is 0:004—-0'007™".
b. Microsclera; these are chelz arcuate; they are small and slender, the shaft is only slightly
curved, the tooth is elliptical; the ale are connected with the shaft for about their whole length and
the chela thus greatly resembles a palmate chela, or might perhaps even be termed so; the length
of the chela is 0'1025—o030™ and the thickness of the shaft oo002™. The chele are seen singly in
the tissue, and they occur in rather great numbers in the dermal membrane, but they form no layer.

This species is nearly related to 77. platychela and has similar large dermal tornota, but it
differs by the much less spined styli and the small chele, which are quite different in shape, and
finally also by the oscular papille.

Locality: Station 28, the Davis Strait 65° 14' Lat. N., 55° 42’ Long. W., depth 420 fathoms. One

specimen.
The Ingolf-Expedition. VI. 3. 9

66 PORIFERA. III.

20. H. longistylus n. sp.
Pl. VII, Fig. 7.

Incrusting; surface somewhat hispid. Spicula: megasclera; the skeletal spicules acanthostyli with
the base thickened, but not forming a real head, the longer only spined at the base, the smaller in the
whole length, o10o—o92”", not divided into two groups; the dermal spicules subtornota to tornostrongyla

0238—a 28", microsclera chele arcuate 0:025—0°045"™.

Of this species one specimen grows incrusting on a Refepfora; it grows in several places on
both sides of the Refepora and through the holes of this, so that by looking through the holes the
projecting spicules of the sponge are seen bordering the holes; another specimen grows on a stone.
Its greatest extent is 14™", and the thickness does not go beyond o5™™. The colour (in spirit) is
greyish white or white. The sarface is in the present state of the sponge strongly hispid from the long
projecting spicules, but the dermal membrane is in most places damaged; only in some single places
it is seen; it is a thin film, which seems to be in a somewhat loose connection with the other body;
the membrane is provided with scattered dermal spicules. In the places where the membrane is
present, the sponge seems to be somewhat hispid, the longest skeletal spicules being somewhat
projecting.

The skeleton. The dermal skeleton consists of loose fibres and scattered spicules which are
placed between the longest of the skeletal spicules; in the membrane itself there are found horizontal,
scattered spicules. The fibres or bundles may in places be somewhat thick. The main skeleton is
formed in the ordinary way of vertical acanthostyli; the longest of them project beyond the surface,
thus making the sponge strongly, but somewhat dispersedly hispid; the styli are not placed densely.
There seems to be some spongin at the base, but I could not observe it with certainty.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; the longest are slightly
curved, the small are straight. In the large styli the head end is thickened, but a real head is not
marked off, in the small styli the head is more distinctly marked; the styli taper into a long, fine
apex; the largest ones are only spined at the base, the small in the whole length, and the spines are
relatively largest in the small styli' The length varies exceedingly, but all intermediate sizes are
found, the smallest are present in greatest numbers. The length is o10—o'92™" and the diameter of
the head oor4—o'028™". 2. The dermal spicules may best be termed tornota, the ends may be
slightly swollen, most frequently this is only the case with one end which then has a distinct, short
point, while the other end sometimes is somewhat rounded, so that the spicule might be termed a
tornostrongyle; the spicules are straight and not thickened in the middle. The length is 0:238—0:28™™"-
and the diameter o:0028—o005™". b. Microsclera; these are chele arcuate, they are of conimon
shape with an elliptical tooth and lobe-shaped al; the shaft is evenly curved and somewhat flattened.
The length is oo25—o'045™" and the diameter of the shaft o:0028—o'007™" in relation to the size and
to whether the chela is seen in side or in front view. ‘The chelz are found scattered in the tissue,
but not, or only singly, in the dermal membrane.

This species shows some resemblance to H. perforata and curvichela, but perforata has shorter

styli and pure tornota, and also the main skeleton is much more dense; curzvichela has similar styli,

PORIFERA. III. 67

but the dermal spicules are polytylote strongyla and the chelz are very strongly curved; it is also
related to H. similis, but it is, as mentioned under this species, distinguished by the small styli being
straight, and by differences in the dermal spicules and the chelz; also the styli in |szmzlzs are distinctly
divided into two groups.

Locality: Station 7, 63° 13' Lat. N., 15° 41' Long. W., depth 600 fathoms, and at 61°09! Lat. N.,
7° 54’ Long. W., depth 180 fathoms, (Ad. Jensen, the cruise of “M. Sars” 1902). Two specimens in all.
The localities lie South of Iceland and West of the Farée Islands.

a1. H. occulta Bow.
Pl. III, Fig. 6, Pl. VII, Fig. 8.

1874. Hymedesmia occulta Bowerbank, Mon. Brit. Spong. II, 250, III, Pl. LX XIX, figs. g—11.

1894. Desmacidon occultum, Hanitsch, Trans. Liverp. Biol. Soc. VIII, 180.

1894. Hymeraphia occulta, Topsent, Rev. Biol. du Nord de la Fr, VII, 12 et 21.

1904. Leptosia occulta, Topsent, Résultats des camp. scient. du Prince de Monaco, Fasc. XXV, 186,
Pl. XV, fig. 1.

Incrusting; surface smooth, generally with a number of papille, bearing oscula and pores, and
with a dense skeleton of dermal spicules in the wall. Spicula: megasclera; the skeletal spicules acantho-
styli with a small, but distinct head, divided into two groups, larger, only spined below, o47—r19”";
smaller, entirely spined, o119—0°26""; the dermal spicules tornota to oxea o-34—0'50"”",; microsclera

chele arcuate with relatively small end parts, 0:034—0'040"™.

Of this species we have some specimens growing on stones, pebbles, small shells and one on
a tube of Placostegus tridentatus. Most specimens are rather small, only reaching to an extent of
12™"; only two specimens, growing on larger stones, have a greatest extent of 18 and of 20™™; the
thickness reaches at most 1". The colour (in spirit) is whitish grey or brownish. The szrface is
nearly smooth, but seen with a lens it shows small, punctiform projections, caused by the skeletal
spicules reaching the dermal membrane, but not piercing it. The surface may otherwise have a
different aspect; in some specimens, especially the small ones, it shows no or only few and imper-
ceptible papillae, but in the larger and best developed specimens the surface bears a number of
papilla, often rather close-standing; the papille are conical or nearly cylindrical, and may reach to a
height of about 15™™, but the exact length cannot be given, as one side of the wall is generally
shorter than the other, the papille lying somewhat down towards the surface. The dermal membrane
is a transparent, somewhat solid and easily separable membrane; it has an irregular skeleton of hori-
zontal spicules and is more or less densely filled with chele, which form, however, no layer. Oscula
and pores: the papillae mentioned are both oscular and pore-papille. “The oscular papille are more
conical and tapering than the others and have a simple oscular opening at the summit; the pore-
papillae are broader at the tip and have here a membrane with pores. Bowerbank, who had
only one small specimen, does not mention papille; Topsent, on the other hand, has perhaps
seen something of the kind, as he says (l, c 186) that the sponge somewhat resembles a small
Hamacantha.

68 PORIFERA. III.

The skeleton. ‘The dermal skeleton; the dermal spicules form bundles which stretch almost
from the base of the sponge and upwards, thus occupying the whole space between the base and the
dermal membrane, lying in different directions between the erect styli of the skeleton. In the dermal
membrane the spicules lie horizontally, more or less densely, but quite irregularly, they lie singly
or here and there a couple together; the membrane is thus provided with a proper skeleton. The
skeleton in the wall of the papille is formed of spicules lying parallel to the longitudinal axis of the
papille and very densely, and it is formed both of the spicules lying in the membrane, and of those
stretching from the underlying skeleton up in the wall. Besides the mentioned skeleton the membrane
is somewhat densely charged with chele which are specially numerous in the pore-membrane in the
papille. The main skeleton consists of erect acanthostyli with the heads placed on the substratum;
the longest of them reach through the whole thickness of the sponge up to the dermal membrane.
At the base there is a not very conspicuous amount of spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are divided into two
well defined groups; the large ones are long and evenly tapering; they are slightly curved, the
curvature as a rule placed more or less near the base; the head is only slightly swollen, but, however,
somewhat distinct, it is densely beset with spines which are blunt; from the head and a little way
out there are spines, decreasing in size outwards, the remainder of the shaft is smooth, or has only
scarcely perceptible and scattered grains. The small acanthostyli are straight or nearly so; they have
a small head which, however, seems larger on account of its somewhat long, radiating spines; they
are spined in their whole length, the spines on the shaft are reclined. The length of the long
acanthostyli is o47—119™", and the diameter of the head 0025—0037™", the small styli are o119—
0:26" long, with a diameter of the head of oo20—0'025™". Small individual variations in size may occur.
Developmental stages of both sizes of the styli were seen in small numbers, showing that the two sizes
are essentially different from the beginning. 2. The dermal spicules are tornota with intermediates
to oxea; they are straight and long tapering; they vary a good deal in thickness, when they are thin
they may be termed tornota, but often they are more fusiform and are then oxea; their length is
0'34—0'744™" with a thickness of o008—o013™. Besides these spicules there are some stronger,
especially thicker, and fusiform oxea of a length of 038 -o'50™" and with a thickness in the middle
of oo17—o'028™". — With regard to these latter spicules the facts are somewhat curious; they are
mentioned both by Bowerbank and by Topsent, and both authors say, that they are present only
in small numbers. But they seem to be subjected to great variations with regard to the number in
which they are present; generally they are only found in very small numbers, and such is the case
in most of my specimens; but in one specimen they are very numerous; whether they are few or
many they are always only present in the dermal membrane, and lying horizontally, but they are not
found in the bundles which stretch down into the sponge; in the specimen mentioned, with numerous
thick oxea, the horizontal spicules in the dermal membrane are almost all of this kind; as the skeleton
in the wall of the papille is formed both of the spicules lying in the membrane itself, and of those
belonging to the fibres stretching up into the wall, the skeleton of this latter consists consequently
outwards of thick oxea, but inwards of thin ones. In the specimen with numerous thick oxea these

are at the same time thicker and upon the whole larger than in the other specimens. — Develop-

PORIFERA. III. 69

mental stages of the dermal spicules were seen in small numbers, they show that these spicules are
diactinal from the first beginning. b. A/icrosclera; these are chele arcuate; they have an evenly
curved shaft, the terminal parts are relatively small, and the ale are somewhat triangular; the length
is 0'034—0'040™"; the shaft is not cylindrical but a little flattened, the thickness is in relation to this
0:003—0'005""._ The chelz occur through the whole sponge and outermost in the dermal membrane;
they are especially numerous in the pore-membranes.

Locality: Station 18, 61° 44' Lat. N., 30° 29’ Long. W., depth 1135 fathoms; station 46, 61° 32' Lat. N.,
11° 36’ Long. W., depth 720 fathoms; station 64, 62° 06' Lat.N., 19°00’ Long. W., depth 1041 fathoms;
station 85, 63° 21' Lat.N., 25° 21' Long. W., depth 170 fathoms. The localities are situated in the
southern part of the Denmark Strait, South of Iceland and between Iceland and Farée Islands.

Geogr. distr. The species was described by Bowerbank from Scotland, depth 96 fathoms; Top-
sent l.c. records it from the Azores in depths of 448, 620, 756 and 1200 fathoms. It seems thus to
have a very wide bathymetrical range, from 96 to 1200 fathoms.

22. H. simillima n. sp.
Pl. III, Fig. 7, Pl. VII, Fig. 9.

Incrusting ; surface smooth, bearing small oscular papille and very low, portferous warts, both
with a dense skeleton of dermal spicules in the wall. Spicula: megasclera; the skeletal spicules acantho-
styli with a small or no marked head, divided into two groups, large, only spined at the base, o-41—
o-65"™, small, nearly spined tn the whole length, o16—o19"™"; the dermal spicules oxea with inter-

mediates to tornota, 032-047"; microsclera strongly curved chele arcuate o028—o0037”™".

_ Of this species we have several specimens of various sizes, growing on larger and smaller
pebbles, shells, Brachiopods and tubes of Placostegus tridentatus. ‘They are present in the material
in all sizes from quite small up to an extent of 30"; the thickness is at most o7™™. The colour
(in spirit) is white to greyish white. The surface is smooth, without projecting spicules; other-
wise it may have a somewhat wrinkled appearance on account of the papillae and impressed areas
to be mentioned hereafter. The dermal membrane is a thin, but distinct and separable membrane; it
rests on the skeleton below and is densely filled with chelez, but has no proper skeleton of horizontal
dermal spicules. Oscuda and pores: in the somewhat large and well developed specimens oscula are
always found, they are conical papille with a simple opening at the summit. The pores are also
limited to certain areas, which may be described as very low, broad warts, somewhat recalling
the structures in /z/flatella viridis. They are bounded by a low wall, being generally lower on one side
than on the other, the wart lying down towards the surface; the pore-membrane closes the opening
and forms a sieve, it is densely filled with chele. The pore-areas may be of various, generally
relatively large diameters, up to 3™". When the sponge is examined with a lens, the pore-areas are
only seen with difficulty; as they are so very low the pore-membrane is always sunk down on the
tissue below and the pores not to be seen, and therefore the only thing seen is a circular, depressed
area, surrounded by a sharp edge.

The skeleton. The dermal skeleton; the dermal spicules form bundles and short fibres stretching

7O PORIFERA. IIL

from the main skeleton, often almost from the base, upwards to the dermal membrane which rests on
them; above they are more or less penicillately spread; they are somewhat perpendicular or more
oblique and often somewhat decumbent. The skeleton in the wall of the oscular and pore-papille is
formed by fibres stretching up in the wall and here forming a skeleton of close-lying, parallel spicules.
There is no skeleton of horizontal spicules in the membrane, but this is provided with dense-lying
chele. The main skeleton is of the typical construction formed by vertical acanthostyli with their
heads placed on the substratum; the longest of the styli may reach to or near to the surface. Spongin
is present at the base, but only to a very slight degree.

Spicula.: a. Megasclera. 1. The skeletal spicules are acanthostyli which are divided into two
rather well defined groups of sizes. The large styli are straight or generally slightly curved near the
head, this latter is small or not at all pronounced; the spines are only present on the head and a
little way out, being here smaller and soon quite disappearing. The small styli are straight, the head
is very small and for the greatest part due to the somewhat longish, radiating spines; the style is
spined nearly in the whole length, only a small apical part being smooth; the spines are often
reclined; they are of moderate size or small, and in this respect there may be some difference in
different specimens. The length of’the large styli is o41—o65™" with a diameter of the head of
0°020—0'028™", and of the small styli o16—o19™" and the thickness of the head about o021™™", 2. The
dermal spicules are oxea with transitions to tornota; they are straight and generally more or less
fusiform and somewhat long tapering and in this case they are oxea, the thinner ones are more
cylindrical with shorter points and must be termed tornota. The length, which may vary a little in
various specimens, is on the whole 0-32—047™" with a diameter in the middle of oo06—o014™™. The
spicules have generally not quite equal ends, but one end is slightly thinner than the other; the
thinner the spicule is the more pronounced is this difference, and some few very fine developmental
stages were quite monactinal, thus showing that the spicule begins as monactinal. Besides the
mentioned dermal spicules there are also in this species, as in the preceding one, some thicker, fusi-
form oxea, they have a length of o'29—0'35™™" with a thickness in the middle of oo15—o017™; they
are very scarce, and as the measurements show, they seem to be connected in size with the ordinary
spicules, only being specially short and thick, and in contrast to the case in the preceding species they
are here shorter than the ordinary dermal spicules. So far as I have seen, these thicker spicules are
found in the outer part of the fibres, just at the dermal membrane. b. AZcrosclera; these are chele
arcuate; they have a strongly, sometimes semicircularly curved shaft, the ale are lobe-shaped, and
short and round; the length is o028—0037™", the most strongly curved may sometimes be a little
shorter; the shaft is somewhat flattened, its thickness is in accordance herewith 0o004—0:007™";
developmental stages were seen in small numbers. The chele are seen through the whole sponge,
but only in small numbers, in the dermal membrane they form on the other hand a more or less
dense layer, and they are numerous in the pore-membrane.

This species is rather similar to and seems also nearly related to H/. occulta, but it is charac-
teristically distinct; as to the skeleton it is distinguished by the absence of a proper dermal skeleton,
and with regard to the spicules the chele have a different shape and are much more curved; also the
difference in the development of the dermal spicules with diactinal beginning in one and monactinal

PORIFERA. III. ar

beginning in the other species is to be noticed. — I think it very probable, that the specimens
mentioned by Topsent (I. c.) from stations 600 and 899, and which the author refers with some doubt
to H. occulta, belong to the present species, as he declares the spicules to be somewhat smaller, and
especially as he observes, that the chele are more curved than in the typical occudta; his figures
belong on the contrary certainly to occzlta.

Locality: Station 9, 64° 18' Lat. N., 27° oo' Long. W., depth 295 fathoms; station 54, 63° 08’ Lat. N.,
15° 40’ Long. W., depth 691 fathoms; station 85, 63° 21’ Lat. N., 25° 21’ Long. W., depth 170 fathoms;
station 98, 65° 38’ Lat. N., 26° 27’ Long. W., depth 138 fathoms; further it has been taken East of the
Farée Islands, depth 250 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902), at 66° 20' Lat. N., 25° 12"
Long. W., depth 96 fathoms (Wandel), and at Angmagsalik in East Greenland, depth 140 fathoms (The
Amdrup Expedition 1900). The localities are situated at East Greenland, West and South of Iceland
and East of the Farée Islands; the bathymetrical range goes from 96 to 691 fathoms.

If the species mentioned by Topsent with more curved chele and smaller spicules should
prove to be the present species, it has also been taken at the Azores in depths of 185 and 106 fathoms.

Remarks: The two species H. occulta and simillima show great resemblance, and they might
be thought nearly related if it were not for the difference in the manner of development of the
dermal spicules. The existence of this difference is very interesting, but it is not, however, possible
to decide for the present its real importance. — The occurrence of special dermal spicules besides the
ordinary ones is also an interesting fact; these spicules seem to be only extreme variations of the
ordinary form, and we have then here again a fact, showing that the spicules placed outermost in the
sponge may be liable to special variations, such as I have pointed out more particularly in Part II of
this work (p. 32—33); also the difference in the abundance of these spicules in different specimens

of the same species, as shown by occulta, has its parallel, as mentioned at the place cited.

23. H. baculifera Tops.
PL Vili, Figss:

1901. Leptosia baculifera 'Topsent, Arch. de zool. exp. et gén. 3, IX, 354.
1904. a — Topsent, Résultats des camp. sc. du Prince de Monaco, Fasc. XXV, I9gI1,
Pl. XV, fig. 2.

Incrusting; surface without projecting spicules. Spicula: megasclera; the skeletal spicules acantho-
styli with a distinct head-swelling, spined in the whole or nearly the whole length, o:077—0.214"", not
divided into two groups; the dermal spicules strongyla varying to subtylota o15—o0'238""; microsclera

small chele arcuate’ o021—0'025””.

This species forms very thin incrustations on stones and on tubes of Placostegus tridentatus
and other serpulid tubes. The greatest extent to which any of the specimens reach is 38™", and
the thickness is about o3™". The colour (in spirit) is whitish to brown. The surface has no projecting
spicules, but seen with a lens it is finely gritty, caused by the skeletal styli. The dermal membrane
is a thin film, it is filled with microscleres and supported by dermal spicules. Oscuda and pores I was
not able to detect.

72 PORIFERA. IIL

The skeleton. The dermal skeleton. Besides the chelz filling the dermal membrane, this is
supported by bundles of dermal spicules, which stretch upwards from the main skeleton; further some
scattered spicules are present in the membrane. The mazz skeleton consists as usual of vertical
acanthostyli with their head-ends fixed on the substratum. The longest of the styli reach to the
dermal membrane, but without projecting through it. A slight amount of spongin seems to be found
just at the substratum, but it is at all events difficult to observe.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli; they are straight or
slightly and evenly curved; they have generally a somewhat distinct head-swelling, and they taper
from the head into a long apex, which may be more shortly pointed outermost. The spinulation is
dense in the lower -part of the style, but it is more dispersed outwards; in the longer spicules an
apical part is smooth, while the shorter ones are spined to the point. The spines on the shaft are
reclined, on the head they are placed more densely and are longer, radiating straight out and generally
truncate. The acanthostyli vary much in size, but they are not divided into two groups. The length
is 0077—o'214™", and the diameter at the base is oo11—o028™. In some specimens the styli did not
reach beyond o178™. 2. The dermal spicules are strongyla varying to subtylota; they are straight,
sometimes a little polytylote but only to a slight degree. The ends may be simply rounded but they
are most frequently slightly swollen; they are not equal, one being a little thinner than the other,
and this thinner end shows the most distinct swelling. The length varies in all between o15 and
0°238™"; in the single specimens the variation is only slight. The thickness is about 0:002—o004™".
b. Microsclera; these are chele arcuate; they are rather small, they have an evenly, generally
somewhat strongly curved shaft, but with regard to this curvature there may be some little variation;
the tooth is lancet-like, and the ale of the same length as the tooth. The teeth have such a
direction, that they lie in a straight line drawn from one end of the chela to the other. The
length of the chele is oo21—o025™", and the diameter of the shaft oo0z—o028™. The chelz

occur in great numbers in the dermal membrane, sometimes somewhat scattered and sometimes

quite close-lying; this difference is probably due to the greater or less contraction of the.

membrane.
As I find no characters separating this species from H/. baculifera Tops. I have referred it to
the latter; especially the figures cited appear to me very like the spicules in the present species.
Locality: Station 1, 62° 30' Lat. N., 8° 21' Long. W., depth 132 fathoms; station 9, 64° 18’ Lat. N.,
27° o0' Long. W., depth 295 fathoms; station 54, 63°08’ Lat.N., 15° 40’ Long. W., depth 691 fathoms;
station 86, 65° 03' Lat. N., 23° 47' Long. W., depth 76 fathoms; station 94, 64° 56’ Lat. N., 36° 19’ Long. W.,

depth 204 fathoms; station 98, 65° 38’ Lat. N., 26° 27’ Long. W., depth 138 fathoms; further it has been

taken at 63°12’ Lat. N., 20° 06’ Long. W., depth 270 fathoms (The fishery investigation steamer “Thor”),
and East of the Farée Islands, depths 220 and 250 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902);
in all about 14 specimens. The station on which most specimens were collected was station 85, the
sponge here growing on tubes of Placostegus. The enumerated localities are situated in the Denmark
Strait, South of Iceland and East of the Farée Islands.

Geogr. distr. Topsent records the species from the Mediterranean North of Algiers, and at
38° 35’ 30” Lat. N., 28° 05' 45” Long. W., depth about 660 fathoms.

PORIFERA. III. 73

24. H. levis n. sp.
Pl. VII, Fig. 2.

Incrusting and very thin; surface finely hispid. Spicula: megasclera; the skeletal spicules
acanthostyli with a somewhat swollen head and small spines, o'08—o-25””, not divided into two groups;
the dermal spicules polytylote tylota or subtylota o-16—o-21"",; microsclera small chele arcuate

0'021I— 0024,

The specimens of this species grow on Brachiopods, shells of Astarte and other mussels and
on Placostegus tridentatus. The greatest extent, to which the species reaches, is 19"; the sponge
forms an exceedingly thin incrustation, the thickness is scarcely above o10™. The colour (in spirit)
is light brownish yellow. The surface is finely and densely hispid from projecting skeletal spicules.
The dermal membrane is a thin film. Oscuda and pores were not observed.

The skeleton. The dermal skeleton; the dermal spicules form bundles which go to the surface
in an oblique, often very decumbent direction; these bundles are rather scattered. In the membrane
the chelz are found sometimes rather numerously, at other times more scattered. The main skeleton
consists in the ordinary way of acanthostyli with the head-ends on the substratum; the larger of them
project beyond the surface, making this hispid. A small amount of spongin is found at the base.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which have a somewhat
characteristic shape; they are straight or generally somewhat curved; the head-end is somewhat
swollen, and they taper into a long apex; as they are rather thick at the head-end and are not
especially long, they become slightly club-shaped. The head-end has strong spines, in the small styli
the other spines are also rather pronounced, but in the larger ones the spines on the shaft are small,
the shaft thus almost being merely gritty; in the longer styli the spines are scattered towards the point,
but there is generally no long, smooth apical part. The size varies much, but the styli are not
divided into two groups. The length is oo8—o25™", the styli thus being rather short; the diameter
of the head is about oor4—o03™. 2. The dermal spicules are slender, straight tylota or subtylota
which are distinctly polytylote; they have a generally rather distinct, longish swelling at each end, the
shaft is a little thinner in one end, and the swelling in this end is therefore more marked than in the
other. The length is o16—o'21™", and the diameter about o10028—o004™. b. Microsclera; these are
chele arcuate; they are rather small, the shaft is somewhat strongly curved, the ale are nearly
triangular and the tooth elliptical and of the same length as the ale. The length of the chela is
oo21I—o'024"", and the diameter of the shaft about o70028™", The chele seem to be confined to the
dermal membrane.

This species stands very near to baculifera, but I consider it as distinct; it is especially the slightly
spined acanthostyli which distingush it, and the dermal spicules are also more distinctly polytylote.

Locality: Station 9, 64° 18' Lat.N., 27° oo' Long. W., depth 295 fathoms; station 25, 63° 30’ Lat. N.,
54° 25’ Long. W., depth 582 fathoms; station 85, 63° 21' Lat.N., 25° 21' Long. W., depth 170 fathoms;
station 89, 64°45’ Lat.N., 27° 20' Long. W., depth 310 fathoms; further it has been taken at 62°20! Lat. N.,
5° 17' Long. W., depth 160 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). In all seven specimens.

The localities are situated in the Davis Strait, the Denmark Strait and East of the Farée Islands.
The Ingolf-Expedition. VI. 3. —

74 PORIFERA. Ill.

25. H. bractea n. sp.
Pl. VIII, Fig. 3.

Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules acanthostylt, divided into two
groups, large, with a small head, only spined in the lower part, 0-28—o 36", small, without head, entirely
spined, o12—o'15”™; the dermal spicules tylota o-27—0'50""; microsclera chele arcuate 0:028—0o-034”™.

Of this species we have only a very small specimen, and the description will therefore in some
respects not be quite satisfactory. The specimen grows on a Brachiopod-shell together with a specimen
of Hymenancora duplicata n. g. et sp. (to be described hereafter), and a small specimen of Melonanchora
emphysema. It forms a very small, almost circular incrustation, scarcely two millimeters in diameter
and very thin; it bears about in the middle a low, cylindrical papilla. The colour (in spirit) is greyish,
and the sponge is somewhat transparent. The surface is in the present state hispid from projecting
skeletal styli. About the dermal membrane I can say nothing, and also nothing about forves and oscula;
probably the papilla mentioned is an osculum, but I could not observe it.

The skeleton. The dermal skeleton seems to consist of scattered bundles of dermal spicules,
and it is, so far as I could observe, relatively weakly developed. The main skeleton is constructed in
the ordinary way aud consists of vertical acanthostyli with their heads on the substratum, and it is
somewhat dense; the longest of the acanthostyli project beyond the surface, and it seems to be so
also in the undamaged sponge.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli which are divided into
two groups, large and small. The large acanthostyli are straight, they have a small head-swelling
and taper evenly into a long apex which is a little more abruptly pointed outermost; they are spined
only on the basal part, at most on the half part; the spines are of medium size, largest below; they
are placed most densely on the head-swelling, but more dispersed outwards. The small styli have no
head-swelling; the base is the thickest part and from here they taper evenly to the point, thus as-
suming a club-like shape; these styli are spined in their whole length, the spines at the base radiate
straight out, those on the shaft are reclined. The length of the large styli is o'28—o'36™", and the
diameter of the head is about o02™™; the length of the small styli is o12—o15™" with a diameter at
the base of oo14™. 2. The dermal spicules are straight and somewhat slender tylota, the end-
swellings are distinct but not large; the length varies rather considerably, from o:27—o'50™", and the
diameter of the shaft is 01004—0°007™. b. Microsclera; these are chele arcuate, they have a curved
shaft, elliptical teeth and lobe-shaped but somewhat narrow ale. The length of the chela is 0:028—
0'034™", and the diameter of the shaft o7004--o0'005™. ‘The chele seem to occur through the whole
tissue, but are seen especially at the surface.

Locality: Station 89, The Denmark Strait, 64° 45’ Lat. N., 27° 20’ Long. W., depth 310 fathoms.

26. H. levistylus n. sp.
Pl. VITI, Fig. 4.
Incrusting. Spicula: megasclera; the skeletal spicules acanthostyli with a very small head, only
spined on and just at the head, for the rest smooth, very uniform in Size, o-4g—o48"™; the dermal

spicules tylota varying to strongyla, o-27—0°34""; microsclera chele arcuate o-045—0'052”".

PORIFERA. III. 75

Of this species only one very small specimen is present, growing as an incrustation on the
inside of a Pecten-shell; it is longish and has a greatest extent of only 3:5™". The colour (in spirit)
is whitish. The dermal membrane is thin and densely filled with chele. Oscula and pores were not
observed.

The skeleton. The dermal skeleton consists of bundles and spicules, which are scattered in
different ways from near the base to the dermal membrane; it seems to be rather diffuse; there is no
skeleton of dermal spicules lying horizontally in the dermal membrane, but this latter is densely filled
with chele. The main skeleton seems to be somewhat slightly developed, it consists of acanthostyli
which are all of the same size, and have the heads based on the substratum. I could detect no
spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are very slightly spined, almost smooth
acanthostyli; they are straight or slightly curved and have a slightly inflated head; this latter bears
more or fewer, but generally only few small spines; near the head the style may be very finely
gritty, but for the rest it is quite smooth. The styli are only of one form and very slightly varying
in size, so that small forms do not occur. The length is about 044—048™, and the thickness of the
head is about oo17™. 2. The dermal spicules are tylota, which are straight, slightly thickened in
the middle and with small end-swellings; these latter may be very small or absent, the spicules thus
becoming strongyla; the length is 0°27—0'34"™ and the thickness in the middle o1005—o'007™. b. AZicro-
sclera; these are chelze arcuate; they have a rather curved shaft which is a little recurved at the
outermost extremities, the alz are lobe-shaped and the tooth narrowly elliptical; the length of the
chelz is 0':045—0'052™", and the thickness of the somewhat flattened shaft is ooo5—o008™". The chelz
occur in specially large numbers in the dermal membrane.

This species is easily distinguished and stands somewhat apart on account of its almost smooth
styli, which are all of nearly the same length.

Remarks: It might be thought, that this species represented only a young stage of some other
sponge (a Lissodendoryx), but I do not think this possible. To be sure we have no investigations on
the skeleton of the youngest fixed stages of the sponges which may come into consideration here,
and it is therefore not known, what the first beginning of the skeleton is in species with a reticulate
or dendritical skeleton, and it is not impossible, that the styli may at first be placed vertically. The
structure of the present species seems so fully to conform with that of Hymedesmia, however, that I think
it must be in reality a Wymedesmia; the styli with a somewhat distinct head, and especially the chelz
being crowded in the dermal membrane are good characters of ymedesmia.

Locality: Station 89, the Denmark Strait, 64° 45’ Lat. N., 27° 20' Long. W., depth 310 fathoms.

CY fis 2 Bowerbanki nl. Sp.
Pl. III, Fig. 8a, Pl. VIII, Fig. 5.

Incrusting, thin; surface smooth. Spicula: megasclera; the skeletal spicules short, club-shaped,
strongly and entirely spined acanthostyli of one size o'0g—o'13””; the dermal spicules tylota o-19-—0'238"™ ;
microsclera chele arcuate 0:020—0'034"".

10*

76 PORIFERA. III.

Of this species one specimen grows on a stone together with ZH. clavigera; on the stone
besides grow a Polymastia and a Mesapos; another specimen is growing on a worm-tube. The
sponge has a greatest extent of 12™; it is exceedingly thin, not over o2™™, and its thickness is
not or only slightly greater than the length of the skeletal styli. The colour (in spirit) is whitish,
somewhat milky. The szr/ace is smooth, without projecting spicules. The dermal membrane is
very thin, transparent and not separable; it has no proper skeleton. Oscuda and pores were not
observed.

The skeleton. The dermal skeleton; the skeleton formed by the dermal spicules consists of
bundles lying irregularly between the erect acanthostyli; they are more or less horizontal, but stretch
up to the membrane; also some single scattered spicules are seen, but there is no dermal reticulation.
The main skeleton is of the ordinary structure, consisting of erect acanthostyli with the heads based
on the substratum; as they are of about the same length, they all reach just to the dermal membrane
but none of them project beyond it. I could detect no spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are of a very
characteristic shape and to a high degree recall the styli figured by Bowerbank for H. zetlandica;
they are short and robust, conically tapering and without any head-swelling; they are strongly spined
in their whole length; the spines at the base are radiating straight out, while the other spines are
directed somewhat downwards; the styli are only of one size and not much varying in length; this is
o7og—o'or3™™" and the thickness at the base (the spines, as always, included) oo21™. 2. The dermal
spicules are tylota; they are straight, somewhat thickened in the middle, and the end-swellings are
small; they have a length of o1g—o'238™", and a diameter in the middle of o007—o009™. b. Micro-
sclera; these are chele arcuate which have a somewhat curved shaft and small end-parts, the ale
are somewhat lobe-shaped, rounded downwards, the tooth is elliptical. The chele have a length of
0'020—0'034™" and a thickness of the shaft of o10028—o005™" respectively; the larger sizes are by far
the most numerous. The chelz are present in the dermal membrane in somewhat considerable numbers,
but not at all forming a layer.

This species is evidently nearly allied to . zetlandica; it has the same outer appearance and
skeletal structure, and the shape and dimensions of both megasclera and chelz are in close agreement
as also the fact that the styli are of only one form; but 4. ze¢landica has sigmates, while the present
species has only chelz for microsclera. )

Locality; Station 85, 63° 21’ Lat.N., 25° 21’ Long. W., depth 170 fathoms; further at 65° 50' Lat. N.,
26° 53' Long. W., depth 208 fathoms (The Fishery investigation steamer “Thor”). The localities lie in
the Denmark Strait.— As said above, one of the specimens grows on a stone together with several
other sponges and among these a specimen of H. clavigera (Pl. III, Fig. 8a and b.). These two
Hymedesmia species grow side by side and quite uniting, but they are easily distinguished from one
another by their characteristically different aspects, clavigera is whitish, but appears somewhat darkened
on account of the black stone shining through it; it is hispid and shows the canals as darker points;
Bowerbanki on the contrary is of a milky colour, it has a smooth surface of a quite uniform aspect, not

showing canals,

7

PORIFERA. III. 77

28. H. truncata n. sp.
Pl. III, Fig. 9, Pl. VIII, Fig. 6.

Incrusting, thin; surface smooth, bearing some small cylindrical or conical oscular papille with
a dense skeleton of dermal spicules in the wall. Spicula: megasclera; the skeletal spicules short, some-
what club-shaped, strongly and enttrely spined acanthostyli, truncate al the apex and with a neck-
shaped constriction above the base; they are of one size 0065—0077"™"; the dermal spicules tylota 028

—o369"™,; microsclera chele arcuate o021—0023”".

Most specimens of this species grow incrusting on stones, one specimen on a Brachiopod-shell
and one on a fragment of a mussel-shell; the specimens are of different sizes, the largest reaches an
extent of 40™; the thickness is very small, generally scarcely exceeding o2™. The colour (in spirit)
is light bluish white, somewhat milky. The surface is entirely smooth without projecting spicules. The
dermal membrane is thin and transparent, it is generally easily separable, and seems to be without
spicules, resting on the skeleton beneath, but the facts with regard to the dermal membrane are not
easily understood; the membrane has a curious, skin-like appearance and consistency, and it is
generally filled with cells containing somewhat refringent granules (“cellules sphéruleuses”?), and I
think the mentioned state of the membrane is due to the influence of alcohol; in most of the speci-
mens there is moreover outermost a thin, brownish film, more or less easily separable, which is, I
think, formed by influence of the alcohol on some sort of mucus. Oscuda and pores: In most of the
specimens there are some cylindrical or slightly conical papille on the surface; they may reach to a
length of 3™™; these papille are oscular tubes with the oscular opening at the summit, though in the
present state they are generally closed. The number of papillae present in the various specimens
varies from two to eleven. The two smallest specimens showed no papille. Pores were not observed.

The skeleton. The dermal skeleton consists of bundles of dermal spicules, which stretch from
the main skeleton, or almost from the base, and up towards the dermal membrane; they are thus lying
obliquely or more or less horizontally. In some places the bundles are more numerous than in others,
but most frequently they are scattered and not at ali numerous; the bundles are rather thick, consisting
of numerous spicules. Near the oscular tubes the bundles form fibres which run from various sides
into the oscular papilla and form in the wall of the papilla a dense layer of spicules lying parallel to
the longitudinal axis of the papilla. The maim skeleton: In most places the main skeleton is con-
structed in the ordinary way, the acanthostyli are erect, with their heads based on the substratum;
they reach from the base to the dermal membrane, but do not project beyond it; they are, at all
events in most places, rather close-standing. I could not detect any spongin. Such is, as said, the
structure of the skeleton in most places, and I think these are the places where the sponge is quite
undisturbed; but in many other places this is not so, the acanthostyli may here be lying down
and crossing each other in all directions, and, what is the most remarkable fact, they may be lying
more or less horizontally in or near the dermal membrane; in most places they are then crowded
together, in others they are much more scattered. Whether this condition is normal or not, I am not
able to say with certainty, but I think it is due to contraction, especially as the normal Hymedesmia-

arrangement of the skeleton is seen in many places. It was stated above, that the dermal membrane

78 PORIFERA. III.

appeared to be somewhat transformed by the preservation in alcohol, but the whole sponge is also
evidently highly influenced by the alcohol, the surface being wrinkled to a high degree. I am
inclined to think that the exceedingly thin sponge is somewhat mucous in the fresh state, and then
is highly contracted by the influence of the alcohol, and this would fully explain the remarkable
condition seen in the skeleton.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli of a very characteristic
shape; they are short and straight, slightly tapering towards the point, this latter is broadly truncate,
so that the spicule is nearly cylindrical; they are strongly spined in the whole length, only a little
above the base there is an unspined part, and this part is also a littie thinner than the rest of the
spicule, thus forming a characteristic, neck-shaped constriction; though there is no real head-
swelling, the shape mentioned gives the base of the spicule the appearance of a head. Only very
rarely the neck-formed constriction is less obvious. The length of the acanthostyli is very uniform,
o°065—0'077™", and the diameter at the base is oo17—o'024™". 2. The dermal spicules are tylota;
they are straight and rather robust, and they are of the same or nearly the same thickness in the
whole length, but just before the ends they are somewhat narrowed, and this narrowing gives rise to
the rather slight end-swellings. The shaft is often slightly polytylote. The length is 0:28 —o369™,
and the diameter oo0g—o012™". b. AZicrosclera; these are chele arcuate; they have a curved shaft,
the teeth are so directed that they are lying in a straight line drawn between the ends of the
chela; the ale are somewhat narrow and rather incised in the lower margin when seen in front view;
the tooth is narrowly elliptical. The chelz are small, the length is oo2r—o:023™" and the thickness
of the shaft about o'70028™". Not rarely chelee occur which are thicker and more robust in all parts,
but these give the impression of not being quite normal. The chele are seen in the dermal mem-
brane and in the other parts of the sponge, but generally not in great numbers, on the other hand
they are very numerous on the oscular papille.

This species is nearly related to HW. Bowerbanki, but it is easily distinguished by the characteristic
acanthostyli as also by several other more minute characters.

Locality: Station 85, 63° 21' Lat.N., 25°21' Long. W., depth 170 fathoms; station 89, 64° 45’ Lat. N.,
27° 20' Long. W., depth 310 fathoms; further it has been taken in Forsblads Fjord in Kast Greenland,
depth 50—g0 fathoms (The East Greenland Expedition 1900), at 66° 54’ Lat. N., 15° 38’ Long. W., depth
58 fathoms (“Beskytteren”), South-west of Suderg, depth 180 fathoms (Ad. Jensen, the cruise of “M. Sars”
1902). The localities are situated on the East coast of Greenland, in the Denmark Strait, North of
Iceland and at the Farde Islands.

29. H. latrunculioides n. sp. -

Pl. III, Fig. 10, Pl. VIII, Fig. 7.
Incrusting ; surface smooth, bearing some oscular papille with a dense skeleton of dermal spicules
im the wall. Spicula: megasclera; the skeletal spicules short, conical, very strongly spined acanthostyli
with a neck-shaped constriction above the base; they are o one size 0'065—o0'071"™; the dermal spicules
tylota, but often with such small swellings, that they approach nearly to strongyla, 0.30—o040"™",; micro-

sclera chele arcuate 0:023—0:028”".

PORIFERA. III. 79

This species greatly resembles the preceding one in external appearance. One specimen is growing
on a stone, which it has nearly quite overgrown, its greatest extent may be estimated to 22™"; three
other specimens grow on a stone together with specimens of Hzstoderma physa, Hymedesmia nummulus,
H. filifera and Plocamia sp.; the largest of these specimens is 12™ in greatest extent. The thickness
of the sponge is about 05™". The colour (in spirit) is whitish with a slightly bluish, somewhat milky
tint, but in places it may be shaded brownish on account of a film-like covering, such as mentioned
in the preceding species. The surface is smooth. The dermal membrane is thin and has no proper
skeleton; it is of the same curious, skin-like consistency and appearance as in /vuncata, and it has
very probably been mucous in the living state of the sponge. Oscula and pores: with regard to the
oscula the facts are quite as in ¢vwmcata; on the largest specimen there is a cylindrical, rather large
oscular papilla about in the middle, it has a length of 6™™. Pores were not observed.

The skeleton is constructed quite as in ¢runcata. The dermal skeleton consists of somewhat
scattered bundles of spicules, the bundles generally consisting of rather many spicules; at the base of
the oscular papilla the bundles form fibres which stretch up in the wall of the papilla, here forming
a dense spiculation of close-lying, parallel spicules. The main skeleton consists in the ordinary way
of erect acanthostyli placed with the heads on the substratum; the spicules are rather close-standing.
So far as I could observe there is no spongin present. For the rest the skeleton in most places shows
all the same conditions and alterations as described above under /rwncata, and I think these conditions
are due to the same factors as suggested for this species. Thus the present species also gives the im-
pression of being strongly contracted, and the dermal membrane is obviously wrinkled and folded,
and moreover it also shows numerous cells with refringent granules.

Spicula: a. Megasclera. 1. The-skeletal spicules are acanthostyli of a very characteristic
shape; they may to some slight degree remind one of the discasters in La/runculia. They are short,
thick and regularly conical; they are strongly spined, and the spines are large, radiating hori-
zontally, not reclined; there is no head-swelling, but there is a slightly thinner and unspined part
above the base, forming, as in /vwncatfa, a neck-shaped constriction, and this constriction makes it
seem as if a head-swelling were present; the constriction mentioned and the outermost point are
the only smooth parts. The length is very uniform, o065—o071™ and the diameter at the base is
0022—0'1027™. 2, The dermal spicules are tylota, but the swellings are often so small that they
are nearly strongyla; they are straight with a cylindrical shaft of equal thickness in the whole
length; sometimes they are very slightly polytylote. The length is o-30—o'4o™, and the diameter is
0'7008—o'013"". b. Microsclera; these are chelez arcuate; they have a slightly curved shaft, the ale
are lobe-shaped and the tooth elliptical; the lower edge of the ale is somewhat incised when the
chele are seen in front view. The length is 0023—o028™" and the diameter of the shaft o003—
o:005"". The chele may vary somewhat, being more slender or more robust, and some of them are
found showing a very robust shape, giving the impression of being not normal but influenced by
abnormal deposition of silica. The chele occur especially in the dermal membrane, and on the
oscular papilla they are present in great numbers.

This species is related to the two preceding, but it is characteristically distinguished, especially

by its acanthostyli, but also by several other characters.

80 PORIFERA. III.

Locality: Station 85, 63° 21' Lat. N., 25°21’ Long. W., depth 170 fathoms; station 89, 64° 45' Lat. N.,
27° 20' Long. W., depth 310 fathoms; both localities lie in the Denmark Strait. ;

Remarks: The three species Bowerbankt, truncata and latrunculioides form together with ze/-
landica Bow. a group of related species; ze//andica is however distinguished from the three others by
possessing sigmata; ¢runcata and latrunculioides are the two most nearly related species. A fifth species
which seems also to belong here on account of its uniform acanthostyli and dermal tylota is the 7.
tenutssima Dendy (established by the author under the generic name of M/yxzll/a), and perhaps also a.
sixth species must be referred to this group, viz. H. obtusata Tops. but this latter species has no
microsclera; its curious, obtuse acanthostyli with a little knob at the apex vary a little more than the
acanthostyli in the other species, from o13 to 0'23™".

If the views about the relationship of these species are correct, and they are certainly so at all
events with regard to the first four species, we have an interesting example which shows, that in a
group of nearly related species we may have forms with chelze and sigmata, with chele alone, and
with no microsclera at all. This confirms the view advanced in the introduction to the genus, that
it is not possible to create genera here according to the presence or non-presence of the mentioned
forms of microsclera.

30. H. irregularis n. sp.
Pl. VIII, Fig. 8.

Incrusting; surface partly smooth partly hispid. Spicula: megasclera; the skeletal spicules
acanthostyli with a distinct head, the smaller spined in the whole length, the larger with a smooth
apical part, o'12—0'50””, not divided into two groups; the dermal spicules polytylote styli o-298—o'39””;

microsclera chele arcuate o:040—o 050”.

This species generally forms incrustations on small stones, a couple of specimens grow on
shells of Astarte sulcata; the greatest extent to which the sponge reaches is about 20™", but most
specimens are smaller; three of them, which grow together on a pebble are quite small, the smallest
only 4™™. The thickness is scarcely more than o'5™". The species is of a somewhat irregular appear-
ance, because it, at all events generally, does not grow flat on the substratum but has imbedded in
its base some small particles and gravel. The colour (in spirit) is yellowish grey to whitish. The
surface is in some places smooth, in other places densely hispid from projecting dermal spicules. The
dermal membrane is a somewhat solid membrane, densely charged with chele. Oscula and pores were
not observed.

The skeleton. The dermal skeleton; in the dermal membrane the chelz are close-lying, forming
a layer; the skeleton formed by the dermal spicules is strongly developed; it consists of spicula-
bundles or fibres which stretch from the main skeleton or quite from the base up towards the surface,
outermost the bundles are penicillately spread and support the membrane; the spicules sometimes
terminate just in the membrane, sometimes they pierce it more or less. When the sponge is examined
from above under the microscope, fan-shaped, more or less decumbent bundles of dermal spicules are
therefore seen. The dermal spicules all have the pointed end turned outwards. The main skeleton

consists in the ordinary way of acanthostyli with the head-ends based on the substratum; on account

PORIFERA. III. 81

of the irregularity of the substratum on which the sponge grows, the styli may show some irregularity
with regard to direction. On the same account there may be great difference with regard to the
relation of the main and the dermal skeleton to one another; when the sponge grows directly on the
shell or the stone the construction is the common one, and the larger styli reach to the surface; but
when the substratum is irregular, and the sponge therefore grows thicker in places, the skeleton
formed of the dermal spicules increases in extent and forms fibres going up to the surface; this
skeleton forms in such places the greatest part of the whole skeleton of the sponge, the main skeleton
always remaining formed of the vertical styli attached to the substratum. A small amount of spongin
seems to be found at the base, but at all events only to a very slight degree.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or
generally somewhat curved near the base; the curvature is present especially in the longer styli. The
styli have a distinctly marked, globular head, and they taper into a long, fine apex. As commonly
the small styli are entirely spined, the longer the styli are the more dispersed are the spines, and the
longer a part of the apex is smooth. The spines on the head are densely placed, and they are the
largest; on the shaft they are compressed and reclined. The styli vary much in size; even if the
intermediate forms are rare, there are however not two separate groups of size. The length is o12—
oso™", and the diameter of the head is o1021—o'030™. 2. The dermal spicules are of a very
characteristic shape and must be termed styli; they are straight, one end is rounded, the other tapers
evenly into a long apex which is more abruptly pointed outermost; the spicules are thickest in the
middle, and they are polytylote, showing on the middle part a series of swellings; near the rounded
end there is a somewhat sudden narrowing which forms a handle-like part. The length of the
dermal spicules is o298—o'39™™" and the diameter in the middle o006—oo10™. b. Microsclera; these
are chelze arcuate; they are of ordinary shape with an evenly curved shaft, an elliptical tooth and
ale of the same length as the tooth. The length of the chelze is o1o40o—o050™; the shaft is some-
what flattened, its diameter is in front and side view about 0:004—0'008™" respectively. The chelz are
found, as mentioned, in the dermal membrane forming a dense layer.

Locality: Station to, 64° 24' Lat.N., 28° 50' long. W., depth 788 fathoms; station 16, 65° 43’ Lat.N.,
26° 58’ Long. W., depth 250 fathoms; station 85, 63° 21’ Lat. N., 25° 21’ Long. W., depth 170 fathoms;
further it has been taken in the Denmark Strait at about 65° Lat. N., depth unknown, at 62°29’ Lat.N.,
5° 17’ Long. W., depth 160 fathoms and South-west of Sudere, depth 180 fathoms (Ad. Jensen, the cruise
of “M. Sars” 1902). About ten specimens in all. The localities lie in the Denmark Strait and at the
Far6e Islands.

31. H. proxima n. sp.
Tab. VIII, Fig. 9.

Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules acanthostyli without a real
head, divided into two groups, large, only spined below, o43—0'62"", small, entirely spined, o-14g—

ars"; the dermal spicules styli o:-28—o'33""; microsclera chele arcuate, 0:023—0°035””.

Of this species we have two specimens growing as thin, but rather extended incrustations on

tubes of Placostegus tridentatus. 'The greatest extent of the sponge, which, of course, follows the
The Ingolf-Expedition. VI. 3 Ir

82 PORIFERA. IIL.

longitudinal direction of the worm-tube, is about 30™; the incrustation is very thin and reaches where
it is thickest scarcely o'5™". The colour (in spirit) is light greyish brown. The suz/ace is somewhat
strongly hispid from projecting skeletal spicules. The dermal membrane is a thin, transparent film.
Pores and oscula: some circular openings are found in the membrane, scattered on the surface, they
were measured to a diameter of o7023—0'15™"; probably the smaller openings are incurrent and the
larger excurrent, but no separation into two divided sizes could be observed. When the sponge is
examined with a lens a multitude of canals and cavities are seen in the tissue; they are especially
visible, when the sponge is somewhat dry.

The skeleton. The dermal skeleton; in the dermal membrane the chelz occur numerously, in
some places lying rather densely, in others more scattered. The skeleton formed of the dermal spicules
is somewhat strongly developed; it consists of bundles or fibres stretching from the main skeleton,
often quite from the base upwards and supporting the dermal membrane; the spicules in the
bundles are outermost spread penicillately, and they may project a little through the membrane. The
fibres have often a very oblique or decumbent direction, thereby being longer, and thus, when the
membrane is viewed from above, one may get the impression, that the dermal membrane has a reti-
culation. All the dermal spicules have the pointed end turned outwards. The main skeleton is formed
of acanthostyli with their head-ends based on the substratum, the longest of them project considerably

beyond the surface: There is an amount of spongin at the base, in which the head-ends of the styli
are imbedded, but it is, however, only slightly pronounced.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or %
generally somewhat curved; the basal end is the thickest part of the spicule, but there is no head
developed; they taper evenly into a long apex. The small styli are spined in the whole length, and :
the spines are more or less reclined. In the large styli the spines are relatively smaller, they are
present only on the lower part of the spicule and upwards they become small and gritty. The spines
on the lowermost part are both in the small and the large styli not specially larger than those a
little more upwards. The size of the styli varies greatly, and they are divided into two groups, which
show however no other principal differences than the size. The length of the large styli.is o43—
o62™" and of the small o14—o'18™, the diameter at the base is 0017 and o‘or1™™ respectively. 2. The
dermal spicules are of a characteristic shape; they are styli and have a shape like those in zrregularis
with the rounded end narrowed and handle-like, but they are not polytylote; they are straight or
slightly curved and they have an even, middle-long apex. The length is o-28—0-33™™" and the diameter
in the middle ooo8—oo012™". b. Microsclera; these are chele arcuate; they have an evenly, rather
strongly curved shaft, the end-parts are relatively small, the tooth is lanceolate with a long tuberculum;
the ale are of the same length as the tooth, strongly incised in the lower edge and somewhat tooth-
shaped; the shaft is not flattened. The length is 01023—0035™", and the diameter of the shaft about
0'0038--0'005"". The chele occur, as mentioned, in the dermal membrane, but they are also otherwise
seen in the body of the sponge.

This species is nearly related to the preceding one, HW. irvregularis, it is however distinguished
from this by characteristic differences; thus in contrast to wregularis it is hispid from projecting
skeletal spicules, and the chele do not form a dense layer in the dermal membrane. But the most

,

SORTA Say ara Uy

‘ at ea bi)

ae,

4

PORIFERA. III. 83

characteristic differences lie in the spicules, the acanthostyli have no pronounced head, they are more
slender and are divided into two groups; the dermal spicules are not polytylote, and the chelze have
a diffreent shape and are smaller.

Locality: Station 85, 63° 21’ Lat. N., 25° 21’ Long. W., depth 170 fathoms; the station lies in the

Denmark Strait.

32. H. crux O, Schmidt.
Pl. III, Fig. 11, Pl. VIII, Fig. ro.

1875. Desmacidon crux O. Schmidt, Jahresber. der Comm. zur wissensch. Unters. der deutsche Meere
; in Kiel fiir 1872—73, 1875, 118, Taf. I, Fig. 1o—11.
1903. Hymedesmia crux, Thiele, Arch. fiir Naturgesch. Jahrg. 1903, I, 392, Taf. XXI, Fig. 26 a—-d.

Incrusting; surface smooth, generally with low, oscula-bearing, conical warts with a skeleton of
dermal spicules in the wall. Spicula: megasclera; the skeletal spicules acanthostyli with a well-marked
head, spined in the whole length, o:12—0°'38"", not divided into two groups; the dermal spicules sub-
tornota varying through tornostrongyla to strongyla, they are polytylote, o:27—0°38"" ; microsclera chele

arcuate with a spined shaft, 0:031—0'043””".

Of this remarkable and very interesting species we have about ten specimens; they form small
or more extended incrustations on stones and worm-tubes, one grows on a /ecten-shell; the greatest
extent it reaches is about 35™™, and the thickness lies between o'5 and 1™™. The colour (in spirit) is
yellowish red, brownish red or reddish, the sponge may thus vary somewhat in colour, but it always tends
towards reddish. Schmidt 1. c. says about the colour “braungelb”, and one of the Ingolf specimens
is stated to have been yellow in the fresh state. The sawrface is smooth in so far as there are no
projecting spicules, but it is often wrinkled and folded to a higher or lower degree; this latter fact is
probably only due to contraction. The dermal membrane is rather thick and solid, and it is easily
separable; it is very densely charged with chele, more densely than in any other species of //yme-
desmia; the chele form a dense and solid layer. Oscula and gores: oscula are found as low, conical
warts scattered on the surface; they have an opening or a depression in the summit, and around this
the surface may be a little stellately rugose. In my specimens the warts are, as said, quite low,
sometimes scarcely elevated above the surface; Schmidt says on the other hand “Oscula auf unregel-
missigen Papillen”; according to this it would seem, that the oscular cones may sometimes be higher,
if it is not irregular folds of the surface, that Schmidt has mistaken for cones. In some specimens
the warts are easily discernible, in others they are more or less indistinct, and they may be quite
absent. Pores I have not seen and cannot say whether they are scattered or perhaps collected in
definite areas; sometimes some larger, dendritically branched canals may be seen through the dermal
membrane. |

The skeleton. The dermal skeleton; the most protective skeleton of the dermal membrane is
formed by the mentioned dense layer of chelz; the dermal spicules form bundles stretching from the
main skeleton, often almost from the base, up to the dermal membrane; in the membrane itself no

dermal spicules are found. Around the oscula the dermal spicules form a special oscular skeleton, the
11*

84 PORIFERA. III.

spicules here forming fibres which run stellately to the top or the middle of the cone, but also here
the fibres run below the dermal membrane and not in it, and the dense layer of chele continues just
to the centre of the cone. The main skeleton consists in the ordinary way of perpendicular acantho-
styli with their heads on the substratum; the longest styli reach up to the dermal membrane. At the
base a small amount of spongin is present.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are slightly curved,
generally nearest the base, and they are somewhat densely spined in their whole length; the head is
round and generally well marked; the spines on the head are straightly radiating, on the shaft they
are reclined. The spicules vary much in length, but as all intermediate sizes are present they are
not divided into two groups; the length is o12—o'38™" and the diameter of the head 0:02—003™".
2. The dermal spicules are straight and very slightly fusiform; they may be termed subtornota,
but generally one end is rounded so that they are tornostrongyla and also both ends may be rounded,
the spicules thus being strongyla; they are distinctly polytylote. The length is o-27—038™™ and the
diameter 07006—o'008™". b. Microsclera are chele arcuate of a very characteristic and remarkable
shape; the shaft is very strongly curved, sometimes to so high a degree that its end-parts form two
nearly parallel arms; on the middle of the hinder side of the shaft there are a number of strong
spines. Also the shape of the end-parts of the chela affords great interest; the tooth is protruding
greatly forwards, but it is formed almost entirely of the strongly developed falx, while there is nearly no
plate, the falx only being somewhat thickened at the front edge; the alz are also very interesting,
they quite resemble the falx in shape and they are of the same size, further they are directed straight
out to each side, so that they form right angles with the falx, on the other hand they are not or
almost not bent forwards. The whole construction of the end-parts recalls the construction characteristic
for the ancoree, but I shall otherwise draw no conclusion from this fact at present. The chelz are
nearly always somewhat contorted. Same few developmental stages were seen, they show spines on
the shaft already when rather thin. The length of the chela, which is somewhat dependent on the
degree of the curvature, is 0:031—0043™", and the diameter of the shaft, the spines not included, is
o7005—0'007™", As mentioned the chele form a dense layer in the dermal membrane, but they are
also seen in the other parts of the sponge.

Locality: Station 9, 64° 18' Lat. N., 27° oo' Long. W., depth 295 fathoms; station 81, 61° 44’ Lat. N.,
27° 00' Long. W., depth 485 fathoms; station 85, 63° 21‘ Lat. N., 25° 21’ Long. W., depth 170 fathoms;
station 98, 65°38’ Lat.N., 26° 27' Long. W., depth 138 fathoms; further it has been taken at 65°50’ Lat.N.,
26° 53' Long. W., depth 208 fathoms (The Fishery investigation steamer “Thor”), and West of the Farée
Islands in depths of 160 and 180 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). In all about ten
specimens. The localities lie in the Denmark Strait and West of the Fardée Islands.

Geogr. distr. Schmidt had the species from South-west of Bukenfjord, Norway, depth 106 fathoms.

33. H. aenigma n. sp.
Pl. IX, Fig. 1.
Incrusting; surface for the most part hispid, with some conical projections, bearing oscula-

Spicula: megasclera; the skeletal spicules acanthostyli with no real head-swelling, they are entirely

—- oe

PORIFERA. III. 85

spined, o13—0'34"", not distinctly divided into two groups; the dermal spicules somewhat fusiform,

polytylote tornota, 0:32—0°'43”"; microsclera curtous asteroid chele o0:028—o035™™.

This species grows incrusting on a Brachiopod-shell together with some other incrusting
sponges; it has a greatest extent of 20™™ and a thickness of about o5™™. The colour (in spirit) is
greyish brown. The surface is for the greatest part densely hispid from projecting dermal spicules,
but in one end it is smooth, and here there are a couple of conical projections, forming oscular cones.
As I have only one specimen, I cannot say, whether it is characteristic for the species that the
oscular cones are thus restricted to a special part of the surface. The dermal membrane is thin and
not separable; it is densely charged with the curious chele.

The skeleton. The dermal skeleton, as said the microscleres form a dense layer in the dermal
membrane; the dermal spicules form fibres and bundles stretching in various ways from the main
skeleton or quite from the base up to the dermal membrane; the direction of the fibres is generally
almost horizontal, and they reach therefore some length; they are also rather strong, of an average
thickness of o'042™"; they terminate in the dermal membrane. The membrane is pierced by spicules
which seem to be more or less scattered or forming penicillately spread bundles. As far as I could
observe these projecting spicules rise from the underlying fibres, probably from the ends of these;
they seem to be wanting or are at all events few in number on the smooth part of the surface,
where the oscular cones are found. The fibres formed of the dermal spicules run into the oscular
cones, forming in the wall of the cone a dense skeleton of parallel spicules with the ends towards the
summit of the cone; above this skeleton the layer of microscleres lies. Quite down at the base of the
sponge there is found a number of dermal spicules lying singly and horizontally and thus not taking
part in the formation of the fibres. The maz skeleton is constructed in the ordinary way and consists
of vertical acanthostyli with their heads based on the substratum; the skeleton is not dense, the styli
being somewhat scattered. At the base a scarcely perceptible amount of spongin is found.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or slightly
curved, the basal end is the thickest part, but there is no real head-swelling or only a slight one.
The styli are spined in the whole length, the spines are of small or medium size and reclined; on the
head-end they are larger and straightly radiating. The length is o13—0'34™", and the diameter at
the base is oo14—o'021™. The styli cannot be said to be divided into two groups but the middle sizes
are however rare. 2. The dermal spicules are tornota, they are straight or slightly curved and
somewhat fusiform, and they are more or less polytylote. The length is 032—043™™ and the diameter
in the middle o006—o007™". b. Microsclera; these are bodies of a very curious shape, I may term
them asteroid chele. Roughly speaking they present a cylindrical shaft which at each end divides
into three branches, each bearing at the end four compressed, two-pointed teeth, placed in a square;
the shaft is more or less curved. On closer examination it becomes evident that this curious body is
a chela. It is as a rule possible to trace the shaft or main axis (Pl. 1X, Fig.gc), and one of the three
branches at each end is the direct continuation of the axis; this axis answers to the shaft and the
teeth in an ordinary chela; the two other branches at each end, which are generally a little tninner
than the axis, answer to the alz; they issue from the hinder side of the shaft; but the ends of the
shaft itself and of the alar branches are all developed in the same way, splitting into four compressed,

86 PORIFERA. III.

two-pointed teeth, the exact shape of which may be seen in the figures. Such are the facts generally,
but it is however not always possible to decide, which of the branches belong to the axis, the branches
often being so uniformly developed that they all seem alike. The chela is somewhat contorted, so
that when seen from the end all six branches become visible, and we get a figure almost like a six-
rayed aster. (Pl. IX, fig. 1f). The length of the chela from one end of the shaft to the other is o028—
0035™" and the thickness of the shaft is o004—o005"™". That these bodies are transformed chelz is
seen also from the developmental stages, of which some were found (PI. IX, fig. 1g); these consist of a
curved axis with two lateral dilatations near each end, and they resemble to some degree develop-
mental stages of other chelz, only that the tooth is here not curved forwards. — These chele remind
one somewhat of the chele in H. Schmidti Tops., but are different in many respects; they are very
interesting and take an intermediate position between the previously described, more or less trans-
formed chele; H. crux has normally shaped, but spined chele, . Schmidt has likewise spined chele,
but much more transformed, in H/. wenigma they are still more transformed, and finally we find in
H.. vidua the chele transformed almost to spined staves. — The chelz occur in the dermal membrane
forming a dense layer, and they are also found scattered in the tissue lower down in the sponge.

Locality: Station 89, 64° 45’ Lat. N., 27° 20' Long. W., depth 310 fathoms. The station lies in the
Denmark Strait.

Remarks: While at present only few species are known with spined chele — I think only
the above mentioned and Pseudohalichondria clavilobata Cart. (Ann. Mag. Nat. Hist. 5, XVIII, 1886,
454, Pl. X, fig. 8) — there are on the other hand some fossil forms, described by Hinde and
Holmes (Journ. of the Linn. Soc. XIV, 1894, 214, Pl. XI, figs. 8--14); the authors figure seven chela,
which they think belong to four species, two of which are named as Psewdohalichondria deformis and
oamaruensis. The forms are all referred to the genus Pseudohalichondria Cart. evidently only on
account of the spined chele. As already mentioned by Topsent in his work from 1904, there may
be some reason to think, that the described chele belong to species of Wymedesmia. The chelze were
found in lower Tertiary strata in New Zealand. It is somewhat curious, that such chele are known
as fossil, since the spination and higher or lower transformation of the chele must certainly be
considered as a feature of recent origin. Probably therefore the genus Hymedesmia, containing only

incrusting forms of a simple structure, is an old genus.

34. H. filifera O. Schmidt.
Pl. III, Fig. 12, Pl. IX, Fig. 2.

1875. Desmacidon filiferum O. Schmidt, Jahresber. der Comm. zur wissensch. Unters. der deutsche Meere

in Kiel fiir 1872—73, 1875, 117, Taf. I, Fig. 6.
1903. Hymedesmia filifera, Thiele, Arch. fiir Naturgesch., Jahrg. 1903, I, 391, Taf. XXI, Fig. 25 a—c.

Incrusting, but not thin; surface smooth, bearing a number of thin, cylindrical oscular and pore-
papillae. The dermal membrane solid, with horizontal spicules. The skeleton formed of dermal spicules
strongly developed, the main skeleton rather weak. Spicula: megasclera; the skeletal spicules entirely
spined acanthostyli with the basal end not or slightly thickened, o-13—0°27"", not divided into two

ee ae ee

PORIFERA. III. 87

groups; the dermal spicules strongyla with a slight, double curvature, 027-045"; microsclera chele

arcuate o030—0°035%™.

This species forms thinner or a little thicker incrustations on stones; the surface bears a
number (in the specimens to hand some few to about a dozen) of long papillae, which generally reach
a length of 6™ or a little more; they are cylindrical, generally a little thickened towards the apex,
and they may vary in thickness from quite thin and thread-like to a diameter of about o5™™. The
largest of our specimens has a greatest extent of 25™™; the specimen figured by Schmidt lc. is 35™™
long. The colour (in spirit) is greyish or dirty yellowish. The surface is smooth without projecting
spicules. The dermal membrane is a tough and solid, easily separable membrane which is provided
with horizontal spicules. Oscuda and pores: the mentioned appendages are by Thiele (1. c.) declared
to be oscular papillz, and this is also the case with some of them, but the greater part are pore-
papille; the oscular papillae have a simple opening in the summit, while the pore-papille have here
a pore-sieve stretched over the opening. So far as I could see on my somewhat damaged material
there is also some difference in the shape of the papilla, the oscular papillae being more conical and
the pore-papille cylindrical and somewhat widened towards the apex.

The skeleton. The dermal skeleton; the skeleton formed by the dermal spicules is by far the
largest part of the whole skeleton. The spicules form fibres which run in different directions quite
from the base up to the dermal membrane; these fibres consist of many spicules and are generally
rather thick, they may f. inst. reach to a diameter of 0'36™". In the skin the spicules lie horizontally
and in more than one layer, thus forming a close skeleton; they lie in all directions, but however
somewhat bundle-like; the bundles in the different layers generally cross each other. Finally the
dermal spicules form the skeleton in the wall of the papille; they lie here in the longitudinal direction,
but the spicules in the- different layers crossing each other under acute angles and rather regularly.
The main skeleton is formed mainly in the ordinary way of acanthostyli with their heads on the sub-
stratum; they do not reach to the dermal membrane. Where the fibres of dermal spicules rise from
the base, they are seen to have just their basal end formed by acanthostyli. Spongin is found at
the base. :

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight or very
slightly curved; the basal end is not or only slightly thickened; they taper evenly into the apex, but
the outermost point is not long. They are spined in the whole length, on the base the spines are
large and radiating, giving thus to some degree the impression of a head-swelling; the spines on the
shaft are reclined. The styles vary much in length, but there are no groups. The length is o13—
o727"" and the diameter at the base o7017—o0'028™. 2. The dermal spicules are strongyla; they are
slightly fusiform and have nearly always a curious and characteristic double curvature, more rarely
they are somewhat irregularly curved or nearly straight; the length is 027—o45™", varying a little
in different individuals, and the diameter in the middle is o007—o012™. b. Microsclera are chele
arcuate; they have a regularly curved shaft, the end-parts are not large, the tooth is elliptical, the
ale have generally the lower edge but slightly incised and are more or less triangularly lobe-shaped
in side view. The length is 01030—0035"" and the thickness of the shaft about 01003™. The chelz

are found rather richly in the tissue quite down to the base, they are often abundantly present along

88 PORIFERA. III.

the fibres; in the dermal membrane they are much less frequent, but in the papille they are more
frequent on the inside, and they are very numerous in the pore-sieves.

The identification of this species leaves no doubt according to the description and figures by
Thiele; e. g. his figure of the strongyle with the characteristic curvature is quite in agreement. Schmidt
mentions “Spangen”, and Thiele has also found some single sigmates, but he thinks, that they do
not belong to the species; now it is curious enough that I also found sigmates, but quite singly, and
I think too, that they do not belong to this species; they are very scarce, and as the species always
envelops some incrusted material, it is easily understood, that foreign sigmates may occur in it.

Locality: Station 2, 63° 04! Lat. N., 9° 22’ Long. W., depth 262 fathoms; station 15, 66° 18' Lat. N.,
25° 59' Long. W., depth 330 fathoms, (bottom temperature + 0° 75C.); station 25, 63° 30’ Lat.N., 54° 25’
Long. W., depth 582 fathoms; station 89, 64° 45’ Lat. N., 27° 20’ Long. W., depth 310 fathoms; further it
has been taken at 62° 26’ Lat. N., 4° 49' Long. W., depth 220 fathoms, and 62° 29’ Lat.N., 4° 12' Long. W,, |
depth 283 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). The localities lie in the Davis Strait,
the Denmark Strait and at the Farde Islands. The species is certainly an inhabitant of the warm
area; to be sure station 15 has a negative bottom temperature, but this station is situated at the very
border between the cold and the warm areas.

Geogr. distr. The species was hitherto only known from Norway, South-west of Bukenfjord,
depth 106 fathoms (Schmidt 1. c.).

35. H. grandis n. sp.
Pl. III, Figs. 13—14, Pl. IX, Fig. 3.

Incrusting, but of massive appearance; surface smooth, bearing a number of thin, cylindrical
oscular and pore-papille. The dermal membrane solid, with horizontal spicules. The skeleton formed of
dermal spicules strongly developed, the main skeleton weak, chiefly consisting of bundles of spicules,
forming the lowermost part of the fibres of dermal spicules. Spicula: megasclera; the skeletal spicules
acanthostyli with a very slight or no head, spined almost in the whole length, o41—o75"" (not divided
into two groups?); the dermal spicules long strongyla o-48—o 80”; microsclera two forms, chele

arcuate 0:042—0'048"™", sigmata o'031—0'096™.

The specimens to hand of this species all grow on aggregated, large sponge-spicules; these
spicules are then overgrown, enveloped or more or less imbedded by the sponge; although the species
must thus in reality certainly be considered as incrusting, it has however an outer appearance of
being more or less massive; the upper part of the sponge has at the same time a somewhat bladder-
like consistency which also contributes to its massive outer appearance. The surface bears a generally
great number of long, thin papille or appendages which may reach to a length of 12™" with a dia-
meter of o'5—1'5™". The appendages may be more or less erect or decumbent, and they are generally
more or less curved. The whole sponge is generally folded and wrinkled in different ways. The
species may reach a considerable size, the largest specimen is about 50™™ long and has an apparent
height of 15™™. The colour (in spirit) is dirty yellowish or greyish white. The surface is smooth

without projecting spicules. The dermal membrane is solid and easily separable, and it is provided

*

PORIFERA. III. 89

with horizontal spicules. Oscuda and pores: the mentioned papille are oscular and pore-papille; in
outer appearance there is almost no difference between the two kinds, only the oscular papillce are
generally more conically pointed at the apex, while the pore-papille are more broad here; the latter
are closed by a pore-sieve, while the oscular papillae have a simple opening in the summit. The pore-
papillee are more numerous than the oscular papille.

The skeleton. The dermal skeleton; the skeleton consisting of the dermal spicules forms the
greatest part of the whole skeleton; it consists of fibres and bundles which stretch in an irregular
way from or nearly from the substratum up to the dermal membrane; the course of the fibres is, as
said, irregular, and they are often more or less curved, and may thus be seen running somewhat
parallel with the surface; the fibres may be of very different strength, but often rather thick, up to
o3™", and consisting of many spicules. In the dermal membrane the spicules lie horizontally, but
irregularly, crossing each other in all directions; they lie somewhat scattered, and the membrane is to
be seen everywhere between them; they lie thus much more scattered than in #i/era, and not bundle-
like collected. The skeleton of the papillz is constructed quite as in f#fera, and also here the
spicules cross each other regularly and under acute angles. The main skeleton is quite irregular and
scattered on account of the way in which the sponge grows on the substratum; it forms thick bundles
scattered everywhere between the foreign sponge-spicules and other particles of the substratum, and
always forming the lowermost part of a fibre of dermal spicules; the acanthostyli are thus not at all
evenly distributed at the base of the sponge, but very scattered and only present as bundles, from
which fibres of dermal spicules proceed. The bundles are generally large and consist of many
spicules, they may have a thickness of o5™™, At the base of the bundles there is a distinct mass
of spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are long and slender acanthostyli; they
are straight or nearly so and evenly tapering, but the outermost point is short; they have no or only
a very slight head-swelling and are somewhat densely spined at the base and some way out, but on
the largest part of the shaft the spines are somewhat scattered; at the base and especially a little
above it the spines are somewhat large, but for the rest they are small. The styli do not generally vary
much in length, from o41—0'75™" with a diameter at the base of o021—0:026™"; it will be seen that
there is thus no very great difference in size between the styli; some smaller ones may however be
found, reaching only o18™™ in length, but these are very scarce and perhaps not always present.
2. The dermal spicules are long strongyla; they are straight, sometimes slightly, irregularly curved,
and they may be slightly polytylote; the ends may be very slightly swollen. The length is o48—
o80™", and the diameter in the middle o007—o013™. Microsclera; these are of two forms, chelz
arcuate and sigmata. 1. The chelz have a curved shaft, the free middle part of which is about one
third of the length of the chela, the ale are lobe-shaped, the tooth elliptical, pointed. The length is
0'7042—0'048™", and the diameter of the shaft o7005—0'007™. 2. The sigmata are of common shape,
more or less contorted up to a quarter of a turn; they vary considerably in size, the length is 0-031
—o0g6™" and the thickness relatively o1002—o006""; the larger forms are the most common. The
two forms of microsclera occur at definite places in the sponge; in the dermal membrane both chele

and sigmata are present in equal numbers; the chelee occur moreover in the wall of the papilla,
The Ingolf-Expedition. VI. 3. 12

90 PORIFERA. III.

especially outwards, and in rather great numbers in the membrane forming the pore-sieves, and in
these places no sigmata occur; on the other hand, the chelz do not occur in the inner body, while the
sigmata are present here in enormous numbers, filling the tissue and also occurring everywhere in
the basal parts among the particles of the substratum. The consequence of this distribution of the
microscleres is that the sigmata are far more numerous than the chele.

Embryos. In one of the specimens, which was cut through, some embryos were found; they
reached to a diameter of 065™"; they smallest of them had no spicules, but the larger were richly
provided with microsclera, both chelz and sigmata; both forms were smaller than in the grown
sponge, the chelz o031™ and the sigmata not surpassing o1040™; also in the embryo the sigmata
were far more numerous than the chele. No megascleres were present.

Locality: Station 78, 60°37'Lat.N., 27°52' Long. W., depth 799 fathoms; station 84, 62°58’ Lat. N.,
25° 24’ Long. W., depth 633 fathoms; station go, 64° 45’ Lat. N., 29° 06’ Long. W., depth 568 fathoms. In
all five specimens. The localities lie in the Denmark Strait and on the eastern slope of the Reykja-

nes Ridge.

36. H. digitata n. sp.
Pl. III, Fig. 15, Pl. IX, Fig. 4.

Incrusting or of somewhat massive appearance; surface smooth, bearing some thin oscular and
pore-papille ; the dermal membrane with horizontal spicules. Spicula: megasclera; the skeletal spicules
acanthostylt, divided into two groups, large, without a distinct head and not entirely spined, 0-25—0-31™™,
small, with a distinct head and entirely spined, o-11—o'14”™"; the dermal Spicules tylota o26—o-417™™;

microsclera two forms, chele arcuate 0:034—0'038"", sismata 0'028—o'050%™,
iS

This species resembles the preceding in outer appearance, but the specimens present are small;
we have only two specimens, growing on stones together with other species of Hymedesmia and some
other incrusting sponges. The sponge forms a basal, incrusting or more massive part, from which a
number of long, thin papillze issue; in the present specimens the number of papillz does not exceed three;
they are of the common shape and reach to a length of 7™. As said the specimens are small, the
basal part has a greatest extent of about 5™". The colour (in spirit) is yellowish or whitish. The
surface is smooth, and the dermal membrane constructed as in the preceding species. Oscauda and pores
are connected with the papillz quite as in the preceding species.

The skeleton, The dermal skeleton; the skeleton formed of the dermal spicules consists of
more or less distinct fibres going from the basal skeleton towards the dermal membrane; in the
membrane the spicules lie horizontally, and they are as usual lying close in the wall of the papille
in the longitudinal direction, intercrossing at acute angles. The main skeleton consists of basal acantlio-
styli with their heads on the substratum. Spongin is present, but only to a very slight degree.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are divided into two
rather distinct groups, large and small; the large styli are slightly curved, they are thickest at the
base but without any real head-swelling; they taper evenly but the outermost point is short, and they
are spined in somewhat more than the basal half; the spines are small, only at the base a little
larger. The small styli are straight and have a distinct head, the shaft is beset with relatively large

PORIFERA. III. gi

spines in the whole length, the spines are directed downwards; on the head there are rather long,
radiating spines. The length of the large styli is o-25-—o031™", and the diameter at the base o7021™™;
the small styli are or1—o'14™" long with a diameter of the head of oo21™. 2. The dermal spicules
are tylota which are cylindrical and straight or slightly, irregularly curved; the end-swellings are not
large but distinct; the length is o-26—o417™™" and the diameter in the middle o005—o008™". b. Aficro-
sclera are of two forms, chelz arcuate and sigmata. 1. The chelz have an evenly curved shaft, the
free middle part of which is a little more than the third part of the length; the ale are lobe-shaped
and the tooth elliptical, rounded at the end. The length is 07034—0038™" and the diameter of the
shaft o7o0o5™". 2. The sigmata are of ordinary shape, more or less contorted up to a quarter of a
turn. ‘The length is oo28—ooso™ and the thickness between o002 and o003™. The chelze and
sigmata seem to be present in about equal numbers; the chelee occur in the wall of the papilla, and
for the rest both forms of microscleres seem to occur, so far as I could ascertain, through the
whole body.

This species is distinguished from the preceding in regard to the spicules by the smaller acantho-
styli, the tylote dermal spicules and the much smaller sigmata; also the chele are slightly different.

Locality: Station 89, the Denmark Strait, 64° 45’ Lat. N., 27° 20’ Long. W., depth 310 fathoms.
Two specimens.

37. H. trichoma n. sp.
Pl. III, Fig. 16, Pl. IX, Fig. 5.

Incrusting ; surface Smooth, bearing thin papille. The dermal membrane with horizontal spicules.
Spicula: megasclera; the skeletal spicules acanthostyli with a small head, spined in the whole length,
they are divided into two groups, large, o'20—0'24"", small, o11—o'13”",; the dermal spicules tylota

o-29—0°38"™" » microsclera two forms, chele arcuate o-034—0'042"™, plane sigmata o'058—o-075™™.

Of this species we have only one specimen growing on a shell of an Aséarte; it forms a thin
incrustation of a greatest extent of only 6™, and it bears one long and thin papilla. The colour (in
spirit) is light brownish. The surface is smooth. The dermal membrane is thin and not easily
separated. About oscula and pores I can say nothing, as said, only one papilla is present.

The skeleton. The dermal skeleton; the skeleton formed of the dermal spicules consists of
bundles stretching from near the base to the dermal membrane; in the membrane there are horizontal
spicules, but they are scattered and not at all dense-lying. The maz skeleton is arranged quite in
the ordinary way, consisting of erect acanthostyli with their head on the substratum and evenly
distributed over it; the largest of them reach to the surface. A small amount of spongin seems to
be present.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are straight or
nearly so, the head-swelling is small, and they taper slightly towards the point, which is short; they
are rather densely spined in the whole length, but the spines are small, only longer at the base;
though they do not vary much in length they are yet divided into two distinct groups; the length of
the large styli is o20—0'24™", and of the small o11—o'13™ the diameter of the head is about oo21™",

and it is nearly the same in the large and the small styli on account of the basal spines being larger

13°

92 PORIFERA. III.

in the small than in the large styli' 2. The dermal spicules are tylota, they are straight or
generally slightly and somewhat irregularly curved, often with a curvature recalling to some degree
that found in the dermal spicules of 1. fiifera; the end-swellings are small, sometimes almost dis-
appearing; the length is o29—038™™ and the diameter o'004—0007"". b. Adicrosclera are of two forms,
chelz arcuate and sigmata. 1. The chelz have a curved shaft the free middle part of which is
more than one third of the length, the ale are lobe-shaped, their lower margin not much incised; the
tooth is narrowly elliptical; the length is o1034—o042™ and the diameter of the shaft about 0003 ™™,
2. The sigmata are of common shape, but they are quite or nearly quite plane; the length is not
very variable o'58—o75™, generally nearest the latter size; they are relatively thin, the thickness
being 0.0028™", As far as I have been able to ascertain, both chele and sigmata occur through the
tissue, while in the dermal membrane only the chele occur, but here in great numbers, and in places
lying densely. Of the microsclera the chele are the most numerous.

This species is distinguished from grandis and digitata by its plane, thin sigmata and besides
by characters in the other spicules. ;

Locality: Station 85, the Denmark Strait, 63° 21' Lat.N., 25° 21’ Long. W., depth 170 fathoms.
One specimen.

38. H. macrosigma n. sp.
Pl. IX, Fig. 6.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules acanthostyli with a small
head-swelling, spined in the whole length, but the spines much dispersed outwards, 013-028", not
divided into two groups; the dermal spicules strongyla or subtylota 023—028""; microsclera three forms,

chele arcuate 0:020—0'032"™", sigmata of two forms, large o18—o'208, small 0-06—o'089™".

We have three specimens of this species, one of them grows on aggregated sponge-spicules; it
incrusts these all round, so that they are chiefly situated in the interior of the sponge, but stretching
out here and there. Of the other two specimens one grows on a Brachiopod-shell, the other on a
basalt block. The specimens are rather small, one only about 8™", the others 12™ in greatest extent.
The colour (in spirit) is yellowish white or yellow. The swz/ace is smooth without projecting spicules.
The dermal membrane is thin, it is densely charged with chele and sigmata; some small, circular
openings could be observed in it.

The skeleton is highly irregular and confused in the first examined specimen, viz. that im-
bedding sponge-spicules, on account of the manner in which the sponge envelops the substratum.
The dermal skeleton is represented by dermal spicules which are found scattered through the whole
sponge; in single places they may form a bundle stretching towards the surface; in the dermal mem:
brane they are not seen, or at all events only some few, while, as said, the membrane is filled with
microscleres. In one place the dermal spicules were lying parallel and forming something like a
conical projection — perhaps an oscular cone — but the state of the specimen did’ not allow this to be
decided. The mazn skeleton is still less developed, and the acanthostyli are only present in small numbers;
they are seen here and there with the head based on the substratum but otherwise quite confused and
pointing in all directions. While the skeleton is thus on the whole little developed, the sponge is on

PORIFERA. III. 93

the other hand densely filled with microscleres. When a vertical section is examined, the view is
therefore somewhat curious; in the interior foreign sponge-spicules are seen, and for the rest the
microscleres are predominant, filling the other space, the dermal spicules being only seen scattered
between the other elements, and it is only by close examination that an acanthostyle can be observed
here and there. The condition of the skeleton is, as seen below, due to the way in which the sponge
grows, and the principle of the construction is evidently the same as in the other species of Hyme-
desmia, There seems to be a little spongin at the base of the acanthostyli: — On examining the
other specimens, which only came into my hands later, it proved, that the skeleton was here of the
ordinary construction and the styli were as usually placed on the substratum; otherwise it agreed with the
above description, the other space being occupied by dermal spicules and densely charged with micro-
scleres. Here also the styli of the skeleton were somewhat scarce and arranged very dispersedly. —
It is of some importance to notice the facts with regard to these different specimens, as we see it
clearly proved here, that specimens of Wymedesmia may, when growing on loose material, assume a
shape and a manner of growth which may give rise to mistakes by influencing the arrangement
of the skeleton, though the construction of this latter is principally the same as in species of Hyme-
desmia growing on a flat and firm substratum.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight and the
head-swelling is small or wanting; the spines on the basal part are somewhat large and close-standing,
on the rest they are small, reclined and few in number; the smallest styli are somewhat more spined.
The length is o13—0o'28™" and the diameter at the head about oo20™. 2. The dermal spicules
are straight, cylindrical strongyla or subtylota; the ends are generally swollen, but only to a very
slight degree. The length is 023—038™" and the diameter is 0':0057—0'007™". b. Aficrosclera are three
forms, chelz arcuate and sigmata of two sizes. 1. The chelz are of the common shape, the shaft is
curved, the tooth elliptical and the alz lobe-shaped; they vary somewhat in size, the length is oo2z0—
0'032™™" and the diameter of the shaft o10015—o'0028™. 2. The large sigmata are of ordinary form,
but somewhat elongated and generally only slightly contorted; they are of a considerable and very
uniform size, the length is o18—o'208™" and the thickness ooro—oorr™’. 3. The small sigmata
are of a less regular shape and they are contorted, generally a quarter of a turn or nearly so; their
length %& o106—o089™" and the thickness 01003", As said the microscleres occur in great numbers
all through the tissue; in the dermal membrane all three forms occur, but the chele are here present
in greatest number and very close-lying.

This species shows, in one specimen, a manner of growth quite as is found in grandis, and
it also shows resemblances to this species otherwise, but it is easily distinguished from it and
from the related species by the presence of two forms of sigmata. As seen from the description
I have not been able to decide whether the species in a more perfect state may be provided
with papillee.

Locality: Station 54, 63° 08’ Lat. N., 15° 40’ Long. W., depth 691 fathoms; station 78, 60° 37' Lat. N.,
27° 52' Long. W., depth 799 fathoms; station 89, 64° 45’ Lat. N., 27°20’ Long. W., depth 310 fathoms. The
localities lie in the Denmark Strait and South of Iceland.

94. PORIFERA. III.

39. H. pugio n. sp.
Pl. IX, Fig. 7. ;
Incrusting; surface somewhat hispid. Spicula: megasclera; the skeletal spicules acanthostyli with
a distinct head, only spined on the lower part, they are divided into two groups, large o38—o54™™,
small o12—o:20""; the dermal spicules thin styli 0-27—0°31""; microsclera two forms, chele arcuale

o'021—o'040"™", sigmata, small and curved in a somewhat circular way, plane or nearly plane, o'org

—oo17™™,

Of this species we have one specimen, growing on a stone; it forms a thin incrustation of a
greatest extent of about 20™, and the thickness does not exceed o'5™". The colour (in spirit) is white.
The szrface is somewhat hispid from the projecting acanthostyli. The dermal membrane is thin and not
separable, sparingly provided with dermal spicules, but somewhat more richly with chele. A number
of circular openings of canals are seen shining through the membrane.

The skeleton. The dermal skeleton is not much developed; it consists of dermal spicules which
are, so far as I could ascertain, lying partly more or less horizontal in the membrane, but for the
greatest part projecting. The main skeleton consists of acanthostyli with the heads placed on the
substratum; it is rather dense with the spicules close-standing; the longest of the styli project through
the dermal membrane. The heads of the styli are at the base inserted in a somewhat slight mass
of spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are straight or only
very slightly curved and taper evenly into a long apex; the head is round and not large but distinct.
They are spined at the base and some way out, but the larger apical part is smooth; the spines are
small. With regard to size the styli are divided into two groups, but otherwise they are quite similar.
The large styli have a length of 0'38—o'54™" with a diameter at the head of o1021—0'028""; the small
styli are o12—0'20™ long and the head oor5s—oo21™ thick. The small styli are the most numerous.
2. The dermal spicules are rather thin styli which are cylindrical, straight or slightly curved and
taper into a long and fine point. The length is 027—o31™ with a diameter of about 0003™,
b. Microsclera are of two forms, chelz arcuate and sigmata. 1. The chelz have a sometimes rather
strongly curved shaft and relatively small end-parts; the ale are lobe-shaped but somewhat®narrow,
the tooth is elliptical. The size of the chele is somewhat variable, the length being o021—o040™
and the thickness of the shaft o1004—0006™". 2. The sigmata are very small and fine and they are
somewhat circularly curved, so that the length is not much greater than the breadth; they are plane
or almost plane; the length is oo1g4—o‘or7™ and the thickness ooor™™ or still finer. Both forms of
microsclera are seen especially in or near the dermal membrane.

Embryos. The specimen contained a great number of embryos; they are globular or lentiform
and they were easily seen in the thin sponge on account of their white colour. They have an average
diameter of 0:35™". They contained either no spicules or also developmental forms of the chele but
no megascleres.

Locality: Station 15, the Denmark Strait, 66° 18’ Lat. N., 25° 59’ Long. W., depth 330 fathoms
(bottom temperature +0°75C). Only one specimen.

PORIFERA. III. 95

40. H. consanguinea n. sp.
Pl. IX, Fig. 8.

Incrusting; surface finely hispid. Spicula: megasclera; the skeletal spicules acanthostyli with a
small or no head-swelling, they are divided into two groups, large, with a smooth apical part, o-21—
or2g”™, small, entirely spined, o'10—0'13”"; the dermal spicules tornota, o15—o'19""; microsclera two

Jorms, chele arcuate o-028—o'057”", contorted sigmata o-o1g—o'o017™™,

This species grows as thin incrustations on living Brachiopods and one on a Refepfora; the
sponge covers. generally the whole shell and may thus reach a greatest extent of 16™"; it is exceed-
ingly thin, not reaching o'5™™" in thickness. The colour (in spirit) is whitish. The szzface is short
and finely hispid. The dermal membrane is very thin and hardly observable.

The skeleton. The dermal skeleton is not much developed and somewhat diffuse; it consists
of smail bundles formed by a few spicules; the bundles stretch from the skeleton below up to the
dermal membrane. The mazn skeleton is constructed in the ordinary way and consists of acanthostyli
with the heads based on the substratum; the styli are not densely placed. The longer styli stretch
beyond the dermal membrane, thus giving rise to the hispidity of the surface. So far as I could
observe there is a very small amount of spongin at the base of the skeleton.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are divided into
two well separated groups, large and small. The large styli are straight or generally slightly curved
near the base; they are thickest at the base but have no or only a small head-swelling; they taper
evenly from the base, but the apex itself is not long-pointed; the styli are somewhat densely spined
in almost the lower two thirds, the spines being less dense outwards; at the base the spines are
somewhat large and blunt, for the rest they are small. The small styli have a similar shape as the
large, but they are spined in the whole length. The large styli have a length of o21—o'29™ and a
diameter at the base of o'o18—01025"". The small styli are o10—o13™™ long with a diameter at the
base of about o1014™". 2. The dermal spicules are tornota which are somewhat thin, straight and
cylindrical; the ends have short points; they are not of a simple tornote shape in so far as one end
has a generally slight swelling; sometimes also the other end may show an indication of a swelling.
The length of the tornota is o15—o'19™" and the diameter about o'0025™". b. AZicrosclera are of two
forms, chelze arcuate and sigmata. 1. The chele have a slightly curved shaft and relatively small
end-parts, the alz are lobe-shaped and the tooth elliptical. The length of the chela is oo28—o0057™"
and the diameter of the shaft 07003—o006™. 2. The sigmata are thin and contorted, generally a
quarter of a turn; their length is oo14—oo17 and the thickness o'‘0008™", The microscleres are seen
through the whole tissue of the sponge.

This species shows some resemblance to H. (Hymeraphia) mucronata Tops. with regard to the
different categories of spicules, but the size of these is different for all forms and especially for the
tornota, and there is only one form of chelz in the present species. The species is easily distinguished
from the preceding by the sigmata and the tornote dermal spicules.

Locality: Station 25, 63° 30' Lat. N., 54° 25’ Long. W., depth 582 fathoms, and at 70° 32' Lat. N.,
8° 10’ Long. W., depth 470 fathoms (The Ryder Expedition 1891—g2). In all five specimens. The

localities lie in the Davis Strait and the Denmark Strait.

96 PORIFERA. III.

41. H. planca n. sp.
PL X, Fig

‘

lncrusting; surface densely hispid. Spicula: megasclera; the skeletal spicules acanthostyli with-
out a distinct head, divided into two groups, large, only spined at the base, 035—0'65"", small, spined
about in the lower half, o16—o'27"™"; the dermal spicules tylotornota 021—0o29"™; microsclera three
Jorms, chele arcuate o:018—o'057”", sigmata of two forms, large, contorted, 0:021—0'028"", small,

plane, somewhat circularly curved, o-o14”™.

This species forms incrustations on Brachiopods, shells, Bryozoa and small stones; it reaches a
greatest extent of about 15™™, with a thickness of about o5™". The colour (in spirit) is white in all
specimens. The surface is distinctly and densely hispid. The dermal membrane is very thin and
transparent; it is perforated by a multitude of close-lying circular openings of different sizes, which
are oscula and pores, but there is no such difference in size between them, that it can be decided
therefrom which of them are incurrent and which excurrent openings; the openings are seen only
when the sponge is somewhat dried; when lying in spirit close-standing openings of canals are seen
to shine through the membrane.

The skeleton. The dermal skeleton consists of bundles of dermal spicules, which stretch
obliquely from the lower part of the main skeleton up to the dermal membrane; the bundles are small,
each not consisting of many spicules; the spicules all have the rounded ends inwards and the points
outwards; the spicules in the bundles are a little divergent outwards and bear the dermal membrane,
but they do not penetrate through it or only very slightly; as the longest skeletal styli reach the
dermal membrane and project through it, the bundles of dermal spicules are thus lying between the
ends of the long skeletal styli' The main skeleton is constructed in the ordinary way of vertical
acanthostyli with the heads based on the substratum; it is somewhat dense, and the longer spicules
reach as said to the dermal membrane and project beyond it. At the base of the skeleton there is a
distinctly visible sponginous substance.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli; they are divided into two
distinct groups, large and small; the large styli are more or less curved near the base, this latter is
the thickest part of the style but there is no distinct head; they taper evenly into a long apex which
is a little more abruptly pointed outermost. They are only spined on a short basal part and the
spines are somewhat large. The small acanthostyli are straight and relatively more spined than the
large, the spines are continued to or near to the middle; the spines are also relatively more robust
than in the large styli. The length of the large styli is 035—065™" with a diameter at the base of
o702I—0'028™", and of the small o16—o'27™ with a basal diameter of oo17—o'022™. 2. The dermal
spicules may be termed tylotornota; they ate cylindrical and straight, one end is more or less
thickened or has an oblong swelling which goes however evenly over into the shaft, the other end has
a shorter or longer sharp point. The length is o-21—o29™" and the diameter in the middle 0:003™".
b. Microsclera are of three forms, chele arcuate and sigmata of two forms. 1. The chelz have a
somewhat strongly curved shaft, the end-parts are relatively short, the ale are lobe-shaped and the

tooth elliptical. The length is very variable, from o018 to o'057™", but the shape remains the same.

rR, 7 ar

PORIFERA. III. 97

The shaft is not cylindrical but somewhat flattened and therefore of different thickness in side and
front view, the thickness is in relation to this and to the size of the chela 01003 and o1006™™" to 0007
and oorr™"; the larger chele are the most numerous. Sometimes the chele have the shaft less
strongly curved. 2. The sigmata of the larger form are somewhat irregularly curved and they
are contorted, always a quarter of a turn or nearly so; their length is rather constant, about o021—
o028™" and the thickness about ooor™™. 3. The small sigmata quite resemble the sigmata in Z.
pugio; they are likewise strongly curved, and they are plane; their length is about oo14™" and the
thickness scarcely goes beyond o mm, The microsclera occur through the whole tissue and the
chelze are seen in great numbers in the dermal membrane.

. Locality: Station 15, 66° 18’ Lat. N., 25°59’ Long. W., depth 330 fathoms (bottom temperature
+0°75C.); station 25, 63°30’ Lat.N., 54°25’ Long. W., depth 582 fathoms, and East of the Farde
Islands, depth 230 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902). The localities are situated in
the Davis Strait, the Denmark Strait and East of the Farée Islands. The species must be an in-
habitant of the warm area; it is true that station 15 shows a negative bottom temperature, but this
station lies just at the very border between the cold and the warm areas.

The three species just described must be somewhat nearly related, but besides by other
characters they may be distinguished by their sigmata alone; HW. pugio has only small, plane, circularly
curved sigmata, consanguinca only contorted sigmata and f/anca two forms, contorted and plane.

42. H. cultrisigma n. sp.
Pl. X, Fig. 2.

Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules acanthostyli with a very
slight or no head, they are divided into two groups, large, only spined below, o'56—o'80"™, small, spined
in the basal half, o21—0'30"™; the dermal spicules tylota o-25—o.32""; microsclera three forms, chele
arcuate 0'026—o'0g2™", sigmata of two forms, large, peculiar, somewhat band-shaped, 0:028—o-035””,

small, plane, o'014—o'020"™,

This species grows as very thin incrustations on different bottom material as pebbles and
shell-fragments and in one case on a Hexactinellid skeleton. The greatest extent it reaches is 16™";
it may vary a little in thickness, but it is however always very thin, not reaching o5™™. The colour
(in spirit) is whitish, The surface is in the present condition of the sponge very hispid with long
projecting spicules. The dermal membrane is a thin film. Oscuda and pores were not seen, but some
circular canals could be seen through the dermal membrane.

The skeleton. ‘The dermal skeleton is formed by bundles of dermal spicules stretching from or
almost from the base to the surface; the bundles have a more or less oblique direction and are often
almost horizontal for a distance; they do not project beyond the surface, and there are no spicules
lying in the membrane itself. The bundles are generally weak, consisting of only few spicules. The
main skeleton has quite the ordinary construction and consists of acanthostyli with the heads placed

on the substratum; the long styli project beyond the surface. At the base there is a small amount
of spongin.

The Ingolf-Expedition. VI. 3. 13

98 PORIFERA. IIL

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are divided into two
sizes, large and small; the large styli are slightly curved near the head which is only slightly thickened,
while the other end forms a long-pointed apex; the head and a short space above it are spined, while
the whole of the rest of the shaft and apex is smooth. The small acanthostyli are generally straight and
with the head still less thickened; they are more spined than the large, the spines covering the basal
half part or more, and the spines are relatively larger. The length of the large styli is 0'56—0'80"™,
and the diameter of the head about o'028™", of the small styli o21—o:30"" with a diameter of oo21—
o7025"™". 2. The dermal spicules are tylota; they are straight and the shaft is slender, the end-
swellings are distinct, but they are not formed abruptly but pass gradually into the shaft. The
length is o'25—0'32™" and the diameter of the shaft is o1003™". Some few developmental forms were
found, the thinnest of them being monactinal. b. Microsclera are of three forms, chele arcuate and
sigmata of two forms and sizes, large, peculiar, and small. 1. The chele are of ordinary shape, the
shaft is evenly curved and the end-parts are relatively small; the tooth is elliptical and the ale lobe-
shaped; the shaft is flattened, elliptical in section. The chele vary somewhat in size, the length is
0'026—o'042™" and the thickness of the shaft oo04—o010™"; with regard to the latter measurement
it must be remembered, that the shaft is about twice as thick when seen in front as when seen in
side view. The intermediate sizes of the chelz are scarce and hence they could be said to be present
in two groups of sizes. 2. The large peculiar sigmata are of a curious shape; they may be de-
scribed as having the curved end-parts somewhat long and terminating in a hook; they are contorted
generally a quarter of a turn, and the hooks are again bent a little out of the plane; but the most
interesting feature is that the rod forming the sigma is not cylindrical but compressed and thus
somewhat band-shaped. The size of the sigma from one curve to the other is o1028—0'035™", and the
thickness is oor and o1003™" for the small and the large diameter respectively. 3. The small
sigmata are of ordinary shape and they are plane; the length is oor4—ooz0™ and the thickness
about o0or™, The chele are present especially in the dermal membrane and rather numerous; the
two forms of sigmata are seen through the whole body.

Locality: Station 78, 60° 37' Lat. N., 27°52’ Long. W., depth 799 fathoms; station 81, 61° 44' Lat. N.,
27°00’ Long. W., depth 485 fathoms. In all three specimens. The localities are situated on the Reykja-
nes Ridge South-west of Iceland.

43. H. mucronata Tops.
PL X, Fig. 3.

1904. Hymeraphia mucronata Topsent, Résultats des camp. scient. du Prince de Monaco, Fase. XXV,
165, Pl. XIV, fig. 4a—d.

Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules acanthostyli with no distinct
head, the larger spined at the base, the small entirely spined, 0'12—0°65””, not divided into two groups;
the dermal spicules fusiform oxytornota 0:22—0:268"™",; microsclera three forms, chele of two forms,
ordinary o-021—0'025"™", peculiar, with some processes at each end, 0021-0026", sigmata, large and

Jine, 0°028—o'051”™.

Lat Mee

oe

ES Te eA See aaa Ta a Ph MANNE?

PORIFERA. III. 99

Of this interesting species we have one specimen growing as a small incrustation on an Ony-
chocella; its greatest extent is 8™™, and it scarcely reaches o'5™™ in thickness. The colour (in spirit)
is greyish. The szrface is hispid on account of the projecting skeletal styli. The dermal membrane
is a thin film, it shows a multitude of larger and smaller circular openings representing I think both
oscula and pores.

The skeleton. The dermal skeleton consists of single dermal spicules or of small bundles of
these, stretching from the main skeleton to the surface in a more or less oblique direction. In the
membrane itself there are no horizontal spicules. The maim skeleton has the common construction,
consisting of vertical acanthostyli with the heads placed on the substratum; the longest of the styli
project beyond the surface, thus causing the hispidity of this; the skeleton is somewhat dense. At the
base there is an amount of spongin, which is only slight but forms however a continuous basal lamella.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli which are more or less,
generally only slightly, curved; they are thickest at the base but have no distinct head, and they
taper into a long apex. The larger styli are spined at the base, but the spines are not large and
outwards they become smaller and gritty, and they soon disappear; the small styli are generally
straight, they are spined in the whole length, and the spines are relatively larger than in the long
styli. The styli vary much in size, but there are no separated groups. The length is o12—o65™
and the thickness at the base oor—o024™. 2. The dermal spicules are of a characteristic shape
and may best be termed oxytornota; they are rather thick and much thickened about the middle, so
that they are strongly fusiform; they taper towards each end, one end is tornote-shaped, or sometimes
more rounded, and terminates in a little mucro, the other end is of an oxeote shape, tapering some-
what evenly, but the outermost point is generally short; in some cases this latter end is so short
pointed and has such a shape that the spicule might be termed a tornote. The spicules are often
somewhat curved near the short pointed end. The length is 0:22—0268™", and the diameter in the
middle is ooo8—oo017™". b. Aficrosclera are of three forms, chele of two forms and sigmata; the
chelz are ordinary chele arcuate and peculiar chele. 1. The ordinary chele arcuate have an
evenly curved shaft, the ale are somewhat claw-shaped triangular, the tooth elliptical; the length is
o02I—o'025™" and the thickness of the shaft about oo02™. 2. The peculiar chelz are spicules,
which are somewhat difficult to understand; they consist of a curved shaft the ends of which are a
little dilated and from this dilatation a few processes are produced; the processes may be of different
number and differently, often quite irregularly arranged, but generally there are two larger processes
at the end of the dilated part, and behind these two others, generally smaller processes; it is probable
that the two larger processes answer to a cleft tooth, and the other small processes to ale, but this
it is for the present not possible to decide with certainty; on the other hand I consider it as certain,
that the spicule is a chela and not a sigma. In spite of the number of processes at each end I think
however, that it cannot at all be considered as an ancora; the whole shape of the dilated end-parts
seems to me to point towards a chela. The length of this spicule is ooz21—o026™ and the thickness
of the shaft is about o0028™. 3. The sigmata are of a very characteristic shape, they are rather
large but exceedingly fine, generally they are strongly curved in the middle and the arms have a

hook-formed bend at the end; sometimes they are more evenly curved; they are more or less contorted.
13*

100 PORIFERA. III.

They vary somewhat in size, the length from one hook to the other is oo28—o'051™" and the thickness
about ooor1o™". The microsclera are especially found in the dermal membrane, the ordinary chele
and the sigmata are however also seen throughout the tissue. is

As I have seen a preparation of the type-specimen, kindly sent to me from Professor Top-
sent, the determination is certain; as will be seen the shape and measurements of the spicules agree
very well, only the dermal spicules are different, but I think that Topsent’s figure and measure-
ments are taken from non-typical spicules; the few dermal spicules present in the preparation sent to
me quite agreed with my figure (Pl. X, fig. 3b) and were measured to 0'26™" in length with a
diameter of o1o17™™, °

Locality: Station 25, the Davis Strait 63° 30' Lat. N., 54° 25’ Long. W., depth 582 fathoms. One
specimen.

Geogr. distr. Topsent (l.c.) has the species from 37°55' Lat.N., 25°24' Long. W., depth 465 fathoms.

44. H. tenuisigma n. sp.
Pl. X, Fig. 4.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules acanthostyli with a round
head, divided into two groups, large, only spined below, o-30—0°83”", small, entirely spined, o-1r19—
o16"™,; the dermal spicules long strongyla o:32—042""; microsclera only sigmata which are large, but
thin, 0'084—0'12%™,

Of this interesting species we have two specimens, one growing on an Aséarée-shell together
with H. levis, the other growing on a small Saxicava together with H. Koehleri and H. procumbens.
The greatest extent to which the species reaches is about ro™", and the thickness is at most o6™",
The colour (in spirit) is brownish red. The sez/ace seems, when the sponge is undamaged, to be
smooth. The dermal membrane is a thin film. Oscula and pores were not observed.

The skeleton. The dermal skeleton consists of bundles of dermal spicules which stretch from
the skeleton below to the surface, they thus lie between the apical parts of the long skeletal spicules;
the spicules in the bundles are more or less penicillately spread outwards; the bundles are sometimes
rather large, consisting of many spicules. The maiz skeleton is arranged as usual and consists of
vertical acanthostyli, the longest of which stretch to the surface; at the base there is a small amount
of spongin. .

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli which are divided into
two groups, large and small; the large styli are straight or, generally, slightly curved near the base;
they have a round, more or less swollen head and taper into a long and fine apex which generally ©
is a little more abruptly pointed outermost; the head-swelling is beset with medium sized, blunt spines,
and a short basal part has small spines, the rest of the style is smooth. The small styli are generally
straight, they have a round head-swelling which is however less distinct than in the large styli, it is
likewise beset with blunt spines, and the styli are spined in the whole or nearly the whole length,
but the spines are dispersed outwards. The length of the large acanthostyli is about o:'30—0'83™™;
they vary considerably in thickness from o7020—o'029™" and this has no relation to their length, the

ee ne ee ee ee eee of

PORIFERA. IU. erp here” aes.

longest being often thin; the small styli have a length of orr9g—o'16™" and a diameter at the head of
oo21™. The large styli are generally in size nearest the greatest length, the shorter of them, which
are nearly intermediate between the large and the small, being rare. 2. The dermal spicules are
long and straight strongyla, sometimes one end, and sometimes both may be slightly swollen, in the
latter case the spicule approaching to a tylote; they are as a rule slightly polytylote. The length is
0°32—0'42™" and the diameter o7005—0'007™". Some fine developmental stages were found which were
monactinal. b. Aficrosclera are of one form, sigmata, which are rather curious; they are large but
exceedingly thin, and they are more or less contorted up to a quarter of a turn, otherwise they are
of the common shape. The length is 0084—o12™" and the thickness ooo014™™. The sigmata occur
through the whole tissue but are especially numerous at the surface.

Locality: Station 9, 64° 18' Lat. N., 27° 00’ Long. W., depth 295 fathoms; station 98, 65° 38’ Lat. N.,
26° 27' Long. W., depth 138 fathoms. Both localities lie in the Denmark Strait.

45. H. Dujardinii Bow.
Pl. X, Fig. 5.
1866. Hymentacidon Diyjardinit Bowerbank, Mon. Brit. Spong. II, 224, 38.
1867. Halisarca Dujardinii, Gray, Proc. Zool. Soc. 1867, 520.
1874. Hymeniacidon Dwjardini Bowerbank, |. c. III, 95. Pl. XX XVIII, figs. 1-4.

1882. — — Bowerbank, Norman, ibid. IV, 92, 48.

1888. Dendoryx Duwjardint, Topsent, Arch. de Zool. exp. et gén. 2, V bis, 115, Pl. VI, fig. 3, 12, 13 ¢
1890. _ — , Topsent, Mém. de la Soc. Zool. de Fr. III, 2or.

1891. = — , Topsent, Arch. de Zool. exp. et gén. 2, IX, 528.

1892. - — , Topsent, Résultats des camp. scient. du Prince de Monaco, Fasc. IT, 99.

1892. Myxilla radiata Bow. Topsent, (partim, the last passage), ibid. 109.
1894. Leptosia Dwjardini, Topsent, Mém. de la Soc. Zool. de Fr., VII, 37.

1896. — — , Topsent, ibid. IX, 123.
1896. — _ — _ , Topsent, Résultats scient. de la camp. du “Caudan”, 275.
“190 — — , Topsent, Arch. de Zool. exp. et gén. 3, IX, 353.
1904. — — , Topsent, Résultats des camp. scient. du Prince de Monaco, Fasc. XXV, 185,
Pl. I, fig. 5.

1909. Hymedesmia Diyjardinit, Lndbeck. Meddel. om Grénl. XXIX, 444.

Incrusting; surface smooth; pore-sieves scattered on the surface. Spicula: megasclera; the
skeletal spicules acanthostyli with a globular, more or less marked head, spined in the whole length,
o'083—o'22"™, not divided into two groups; the dermal spicules subtylota to strongyla o:149—0'28"™.
No microsclera.

Nearly all the specimens in my material of this species, and they are rather numerous, grow
as thin incrustations on the shells of a species of Valdheimia, and the specimens of the Valdheimza
were all living; one specimen grows on a mussel-shell, one on a Bryozoa, one on a stone with a speci-

men of Petrosta crassa and finally one on a Voeringia. Otherwise it is recorded as growing on stones,

© tet ee

food fag ie rE bees ts PORIFERA. IIL

shells of Bivalves, Hydroids, and once it is recorded (Topsent 1892) as on an Jnuachus. ‘The
greatest extent to which the sponges in my material ordinarily reach is determined by the size of the
Valdheimia, and is thus about 20™™, and the incrustations are as a rule very thin, scarcely reaching
o5™. The specimen on the stone has an extent of 25™. The colour (in spirit) is generally
pale yellow, sometimes deeper yellow or brownish. Topsent records (1. c. 1888) that it may sometimes

be violet. The surface is smooth. The dermal membrane is delicate and transparent and without —

spicules; it is thin, but when it remains on the sponge in its normal position it is not at all fragile,
and is easily separable; but in most cases the membrane is more or less destroyed, either quite
wanting or remaining only as patches or rags; probably the membrane is in the living sponge soft
and hence easily torn, but on hardening in alcohol it becomes much tougher. Topsent (1. c. 1888)
speaks of “La peau épaisse” but he is here evidently thinking of the whole tissue occupied by the
dermal spicules; in 1892, on the other hand, in the description of the specimens of M/yxilla radiata
which in 1904 he declares belong in reality to W. Dujardinii, he describes a thin dermal membrane.
Oscula and pores: Bowerbank says: “Oscula and pores inconspicuous”, and Topsent (1. c. 1888) says:
“Les orifices aquiféres sont petits”. Oscula I have not observed, but pores I observed on the other
hand in those specimens in which the dermal membrane was in good condition; the pores are some-
what interesting; they are gathered in beautiful sieves which may be present in rather great numbers;
the sieves are generally oval and are seen as slight, somewhat sharp-bordered impressions inclosing a
sieve-like membrane; they are not very conspicuous and require a close examination to be detected,
and they are best rendered visible when the sponge is a little dried. The sieves have generally a
largest diameter of o8—2™™; the pores are dense-lying, more or less oval and of a diameter of
07028—0'08 ™™.

The skeleton. The dermal skeleton consists of fibres, bundles or more loosely scattered spicules
which stretch from near the base and up to the dermal membrane; it may be somewhat differently
developed in different places, in some places it consists only of scattered spicules together with some
few bundles, while in other places the spicules and bundles are much more crowded; sometimes also
the spicules may form rather long fibres running horizontally below the dermal membrane; finally, as
already pointed out by Topsent, the dermal skeleton is naturally most developed in the thickest
specimens, as it alone occupies the space between the basal skeleton and the surface. The main
skeleton consists of vertical acanthostyli with their heads placed on the substratum; they are some-
what distantly arranged; at the base there is a distinct amount of spongin forming a more or less
distinct basal lamella, and the spongin also stretches somewhat up along each acanthostyle, thus
imbedding the lower part of it and forming a distinct coat.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are straight, only
rarely slightly curved; the head is globular, sometimes distinctly marked off, at other times less so on
account of the shaft being rather thick below, but also in this latter case of a globular appearance;
the shaft tapers evenly from the head to the point. The styli are spined in their whole length, only
the spines are sometimes few and dispersed towards the point, and a short outermost part may then
be smooth. The spinulation may vary much in different specimens being more or less dense; the

spines are medium sized and reclined on the shaft, but radiating straight out or curved somewhat

pi)
= at ial le

sages te ha tee tell cal

ro“ ie

PORIFERA. III. 103

upwards on the head, and they may here vary somewhat in length. The size of the styli varies
somewhat, but there are no groups; the length is o083—022™" and the diameter of the head is oor2
—oo2"". The size may be somewhat different in various individuals, the styli sometimes not reaching
over o15™™" in length. 2. The dermal spicules are subtylota varying to strongyla; they are straight
and slender; when they are of tylote shape one end of the shaft is thinner than the other, and this
thinner end has a distinct end-swelling, while the other end is more evenly and but slightly thickened;
the shaft is generally of the same thickness in the whole length, but sometimes somewhat thickened
in the middle. The length of the dermal spicules varies in all from o149—028™, and the diameter
from 0:002—o'005™", but the difference is not so great in the single specimens, as these spicules may
vary to a rather considerable degree in different specimens; thus the following measurements were
taken from different specimens: o'149—o'1I9™", O16—o'20™, O'IQ—0'24™", O'I8—0'28™™" and 0'20—0'28™",
Very often the larger spicules are strongyla or slightly tylote, while the smaller are more distinct
tylota. MMicrosclera are not present.

Embryos. In many of the specimens embryos were found. They are globular and of an average
diameter of 023™™; they are often present in great numbers. Nearly all the specimens examined had
spicules, only a single one without spicules was seen. The spicules are styli considerably smaller
than those of the grown sponge; they were measured from 0':028—o'078™" in length and from exceedingly
fine to o008™" in diameter at the head; otherwise they are acanthostyli chiefly of the same shape as
in the grown sponge, only the spines are less developed, in such a way, that the spicules may be
termed coarsely and rather densely gritty.

It will thus be seen, that the spicules first appearing in the embryo are the skeletal spicules;
this was also to be expected, the same being the case in the A/yxilleae, as I have shown in the second
part of this work in several instances, in the genera M/yxilla, Jophon and Forcepia, in the embryos of
which the skeletal spicules are also the megasclera first appearing. Topsent declares on the contrary
(l. c. 1888, 110), just with regard to the present species, that the first developed spicules are the dermal,
and he says further that this also holds good with regard to Myxilla incrustans. It is somewhat
strange to me how he has got to this result; I can only imagine that he has examined embryos with
very young and fine spicules, in which case these may perhaps be mistaken for dermal spicules.

Locality: This species has been collected in rather great numbers; station 1, 62° 30’ Lat. N.,
8° 21' Long. W., depth, 132 fathoms; station 6, 63° 43’ Lat. N., 14° 34’ Long. W., depth 90 fathoms; station
25, 63° 30’ Lat. N., 54° 25’ Long. W., depth 582 fathoms; station 27, 64°54’ Lat. N., 55° 10’ Long. W., depth
393 fathoms; station 28, 65° 14’ Lat. N., 55° 42’ Long. W., depth 420 fathoms; station 35, 65° 16’ Lat. N.,
55° 05’ Long. W., depth 362 fathoms; further it has been taken at East Greenland, Forsblads Fjord,
depth s5o—go fathoms (The Amdrup-Expedition 1900), and at the Farée Islands, depth 30 fathoms (Th.
Mortensen). The localities are situated in the Davis Strait, at East Greenland, the Eastern coast of
Iceland and the Farée Islands.

Geogr. distr. H. Dujardinii was hitherto recorded from the Eastern coasts of Britain and Ire-
land (Bowerbank); from the French coast of the Channel (Luc, Roscoff, Calvados) (Topsent), the Bay
of Gascogne, depth 95 fathoms (Topsent), the coast of Provence at Ciotat (Topsent), at the Azores in
depths of 69 and 28 fathoms, at 46° 47' Lat. N., 60° 12’ Long. W., depth 72 fathoms (Topsent), finally at

104 PORIFERA. III.

the coasts of North Africa, in the Bay of Gabes and at la Calle (Topsent). The species is thus hitherto
known from 65° to 34° Lat.N., and between 60° Long. W. and 10° Long. E. As to the depth some of
the specimens of the Ingolf Expedition are taken in considerably greater depths than those from
which it was known hitherto; the greatest depth recorded was 95 fathoms, while it was taken by the
Ingolf Expedition in depths down to 582 fathoms. Its bathymetrical range as known now is in all
from the very coast even above low-water mark (Bowerbank) down to 582 fathoms.

Remarks: If the rules of nomenclature were adhered to strictly, the present species should
have a new name, as it is not identical with the well known Halsarca Dujardinii Johnst. Bower-
bank thought, when he examined the present species, that Johnston had overlooked the spicules,
and he identified it therefore with Dwjardini. Already Schmidt has noted (Zweites Suppl. zu den
Spongien des adriat. Meer. 1866, 16) that this must be erroneous. Gray however in 1867 followed
(Lc) Bowerbank. Topsent in 1888 (l.c.) placed the species in the genus Dendoryx, and referred it
later correctly to his genus Lef/osza, but he did not alter its name, which should properly have been
done, since Bowerbank’s determination was erroneous. As the species is well known now under

the name Dzyardini I shall however make no change.

46. H. primitiva n. sp.
Pl. X, Fig. 6.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules acanthostyli with a slight
head-swelling, entirely spined or the larger with a smooth apical part, o-119—0°35"™", not divided into
two groups; the dermal spicules strongyla, slightly polytylote, o:196—o'28"™™. No microsclera.

This species grows incrusting on shells of Brachiopods, mussels and barnacles; it has a greatest
extent of about 20™", the thickness is about o5™™. The colour (in spirit) varies between dark yellowish
and brown. The surface is smooth. The dermal membrane is a distinct but thin film; it was on my
specimens often destroyed to a high degree. Some canals are seen shining through the membrane,
and some oscuda are present as circular openings not elevated over the level of the surface.

The skeleton. The dermal skeleton consists of bundles or quite short fibres stretching from
the main skeleton, often almost from the base, to the dermal membrane; the spicules in the bundles
are penicillately spread towards the membrane and support it, but they do not pierce it. The mem-
brane itself is not provided with spicules or at all events only with some few, lying singly and
scattered; only around the oscula the structure is different; short fibres appear here in the membrane,
stellately arranged all round the opening, towards which they unite in such a way, that the opening
is surrounded by radiately arranged, but not dense-lying single spicules. The main skeleton is of the
ordinary arrangement, the vertical acanthostyli are somewhat densely placed; the longest of them
reach just to the dermal membrane. There is a considerable amount of spongin at the base, forming
a more or less continuous basal layer.

Spicula: a. Megasclera. 1.'The skeletal spicules are acanthostyli, which have only a slight
head-swelling; they are straight or, when longer, slightly curved near the base; they are somewhat
densely spined with spines of medium size; in the longer spicules the spines are small and scattered

Wee ine

.

a

——

Se eee ae

PORIFERA. III. 105

towards the apex, and a shorter or longer part may be smooth. The styli vary much in size but
they are not divided into two groups. The length is o119—0:35™" and the diameter at the base is
oo14—0'027™. The styli may vary somewhat in different individuals, in some they are more robust
and more coarsely spined than in others, and at the same time the smooth part towards the point is
wanting or small. Also with regard to the size there is some variation, the greatest length being in
some individuals 027™". 2. The dermal spicules are straight or slightly curved, cylindrical strongyla;
they are slightly but distinctly polytylote and the ends are generally very slightly swollen, the
swellings being as a rule scarcely perceptible. The length is in all or196—o'28™", but there may be
some variation between the individuals; the diameter is o10028—o005™". b. Microsclera are not present.

This species is characterised towards H. Dwardinit by the size and shape of the acanthostyli
and by the polytylote dermal strongyla.

Locality: Station 6, 63° 43' Lat. N., 14° 34' Long. W., depth 90 fathoms; station 28, 65° 14’ Lat.N.,
55° 42’ Long. W., depth 420 fathoms; station 89, 64° 45’ Lat. N., 27° 20’ Long. W., depth 310 fathoms;
further it has been taken at Iceland, depth 54 fathoms; East of the Farde Islands, depth 160 fathoms
(Ad. Jensen, the cruise of “M. Sars” 1902). The localities lie in the Davis Strait, the Denmark Strait,
between Iceland and the Farée Islands and East of the latter.

47. H. longurius un. sp.
Pl. X, Fig. 7.

Incrusting; surface smooth or nearly so, with scattered pore-steves. Spicula: megasclera; the
skeletal spicules acanthostyli with a small or no head, entirely spined or with a smooth apical part,
o10—o'50"™, not divided into two groups; the dermal spicules strongyla o-22—0:298"™". No microsclera.

This species grows as thin but very extended incrustations on large Balani, on Brachiopods
and one specimen on a Pecten; both the Balani, the Brachiopods and the Pecten were living specimens.
As the species grows along and round the Balani, it may reach to a greatest extent of not less than
75™; the thickness does not reach o'5™". The colour (in spirit) is yellowish or greyish yellow, in
some specimens dark brown or even blackish brown, but probably this latter colour is due to a change
produced later. The surface is smooth or at all events only with a few projecting spicules. The
dermal membrane is a thin film resting on the skeleton below. Oscuda I have not seen, but the fores
are arranged in a somewhat interesting way; they are lying in pore-sieves which are generally
circular; the sieves are surrounded by a very low wall and they are thus seen as slight, circular,
sharply bordered impressions, the borders of which are only a little elevated over the surface; the
whole formation is only little conspicuous, and is generally only to be seen when the sponge is
half dried; in some specimens I could not detect pore-sieves. The pores are close-lying in the sieve
and of an average diameter of o104™".

The skeleton. The dermal skeleton is well developed; it consists of bundles and fibres of dermal
spicules stretching from the main skeleton to the dermal membrane, the outermost spicules in the
fibres are more or less penicillately spread; sometimes the fibres may stretch horizontally below the

membrane for some distance. Around the pore-areas the spicules are radiately arranged and they
The Ingolf-Expedition. VI. 3. 14

106 PORIFERA. III.

stretch into the wall bordering the areas and are here arranged densely and parallel, forming thus a
dense skeleton in the wall. In the membrane itself there are otherwise no spicules, or at all events
only some single, scattered ones. The main skeleton is of the common construction consisting of
vertical acanthostyli with the heads based on the substratum; the longest of them reach to the dermal
membrane or even pierce it. At the base there is a slight amount of spongin.

Spicula: a. Megasclera, 1. The skeletal spicules are acanthostyli which are straight or
slightly curved near the base; the head is small but however generally somewhat distinctly swollen;
in the small spicules it is as a rule not swollen; the styli taper into a long and fine apex. The
spinulation is dense but the spines are somewhat small; in the longer spicules the spinulation is less
dense, the spines become very small and scattered outwards, and in the longest a larger or smaller
apical part, sometimes almost the half part, is smooth. The styli vary very much in size, but are not
divided into groups. The length is o10o—o'50™™ and the diameter of the head oor4—0025™. 2. The
dermal spicules are straight or only slightly and somewhat irregularly curved strongyla; they are
often more or less polytylote, but they may also be quite smooth; one end is a little thicker than the
other, the thinner end has sometimes an elongate, more or less pronounced swelling, which is the
more distinct the thinner the spicules are. The strongyla may vary somewhat in the different
individuals, being in some considerably thicker and less slender than in others; in these thicker
strongyla there is no end-swelling. Some very fine developmental stages were seen which were
monactinal. The length is 0°22—0298™" and the diameter 07003—-01007™". JZicrosclera are not present.

Locality: Station 32, the Davis Strait, 66° 35’ Lat. N., 56° 38’ Long. W., depth 318 fathoms; Ice-
land in @fjord on the Northern coast, depth 18 fathoms (Ditlewsen) and at Hornsvig on the South-
east coast, depth 84 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902).

48. H. aequata n. sp.
Pl. X, Fig. 8.

Incrusting; surface smooth. Spicula: megasclera; the skeletal spicules acanthostyli with a small
or no head, entirely spined, o10—o-30"", not divided into two groups; the dermal spicules strongyla

o'21—o'298"". No microsclera.

This species grows as a thin but extended incrustation on the lower side of a Lithothamnion.
Its greatest extent may be estimated to about 4o™ but is in reality more, as the sponge follows the
irregularities on the underside of the Zithothamnion; the thickness is about o'25™". The colour (in
spirit) is whitish brown. The swz/ace is smooth without projecting spicules. The dermal membrane
is thin and not separable. Oscula and pores were not observed. :

The skeleton. The dermal skeleton consists of bundles or fibres stretching from the main
skeleton, generally quite from the base up to the dermal membrane, at which the bundles are spread
in a penicillate way. The fibres have a more or less oblique direction, and when they are of some
length they stretch horizontally below the dermal membrane. The maim skeleton is of the ordinary
arrangement consisting of erect acanthostyli with their heads on the substratum; the styli are some-

what distantly placed. At the base there is a distinct though not copious amount of spongin.

PORIFERA. III. 107

Spicula: a. Megasclera. 1. The skeletal spicules are somewhat slender acanthostyli; they
are straight or, the longer of them, slightly curved and these latter have a small head-swelling; the
small styli have a very slight head-swelling or often no swelling at all. The styli are somewhat
densely spined with small spines, and they are all, both the large and the small, spined in the whole
length; the spines are relatively largest in the small styli' The length is oro—o30™" and the
diameter at the base oo12—o'017™. The styles are not divided into two groups. 2. The dermal
spicules are strongyla which have one end a little thicker than the other, and they are slightly
fusiform, being a little thicker in the middle than towards the ends; they may sometimes be slightly
polytylote, which is especially the case with the thinner (not fully developed) forms. The length is
o'21—o'298™" and the diameter in the middle o1004—0007™. J“icrosclera are not present.

This species is very difficult to characterise towards the three preceding ones, but it is no
doubt distinct. From Dwyardinii it is distinguished already by the dermal strongyla, as in Diyardinit
there are always at all events some tylota among the dermal spicules; Arimztiva has longer, somewhat
more robust styli with somewhat stronger spines, and distinctly polytylote dermal spicules; /omgurzus
finally is easily distinguished by the long styli which are smooth in a shorter or longer apical part.
Also the small styli without heads are characteristic for the present species.

Locality: At Ikamiut in North Greenland. One specimen.

49. H. dermata n. sp
Pl. III, Fig. 17, Pl. XI, Fig. 1.

Incrusting; surface smooth, bearing a number of conical, compressed oscular and pore-papille.
The dermal skeleton much developed, the main skeleton rather weak. Spicula: megasclera; the skeletal
spicules acanthostyli with a small or no head, divided into two groups, large, only spined below, o-30—
Ogi7"™, small, spined in the whole length o:107—0'13""; the dermal spicules long strongyla 0-33—0°45”".

No mtcrosclera.

Of this species we have a couple of specimens growing on a branching Bryozoon, and one
growing on a stone; the latter specimen is incrusting in the common way, but the specimens growing
on the Bryozoon quite envelop the branches of this, and they also extend between the branches, filling
the interspaces with their body, which however in these places is thin and plate-shaped. The greatest
extent of the species is about 35™", and the thickness of the incrustation may reach 1'5™™. The colour
(in spirit) is whitish or yellowish white. The saz/ace is smooth, without projecting spicules, it bears
a number, smaller or greater, of conical papille; these papille are highly compressed and are generally
lying quite down towards the surface with a flat side turned upwards, and the arrangement is then
such, that the opening, which lies in reality in the summit, comes to lie at the summit of the side
of the papilla, which is turned upwards. The dermal membrane is a thin and separable film; it has
no skeleton proper, but the tissue lying below it, and which has horizontal fibres, is liable to be
separated off together with the membrane, the whole thus giving the impression of a thick and solid
membrane. Oscuda and pores are certainly situated on the papilla mentioned; most of these show a

rather large opening at the summit, while some others are more pointed and conical with a small
14*

108 PORIFERA. III.

opening; I have not seen pore-sieves but the papille with the large opening are in all probability
pore-papille, the others being oscular papille, the facts being thus as in H. verrucosa.

The skeleton. The dermal skeleton; the skeleton formed by the dermal spicules is by far the
most developed and it occupies nearly the whole body of the sponge; it consists of fibres which
stretch from the main skeleton or quite from the base and obliquely towards the surface, but they run
generally so obliquely, that they are for long distances more or less parallel with the surface, and the
skeleton is on the whole rather irregular on account of the manner in which the sponge grows; the
fibres are somewhat numerous and they are also rather strong, of a thickness up to o12™. The
fibres stretch horizontally just below the dermal membrane and terminate in it, but there are no
spicules proper to the membrane. The fibres lying below the membrane run together at the base of
the oscular and pore-cones and continue up in the wall of these, forming thus a skeleton which consists
of densely placed parallel spicules with the ends towards the opening of the cone. The main skeleton
is somewhat weakly developed and consists as usual of acanthostyli with the heads based on the sub-
stratum, but the styli are much scattered and not numerous. At the heads of the acanthostyli there
is a very small amount of spongin.

Spicula: a. Megasclera. 1..The skeletal spicules are acanthostyli which are divided into
two well separated groups, large and small. The large styli are straight or slightly curved, the head
is small or not at all developed; they taper evenly outwards but at the end they are abruptly pointed
with a short point; they are spined only on the basal part at most in the lower half part; most of
the spines, especially those on the head, are somewhat strong. The length is 030—o417™" and the
diameter of the head oo18—o022™". The small styli are straight and spined in the whole length, but
the spines are small and scattered in the outer patt, otherwise they are relatively robust; these styli
are somewhat uniform in size, the length being o107—o'13™" and the diameter of the head oo14—
oor1g™. 2. The dermal spicules are long and straight strongyla with one end thicker than the
other; they may be slightly polytylote; the ends may sometimes be very slightly swollen, especially in the
thinner strongyla. The length is 0°33 —0'45™™ and the diameter o1006—oo010™". A“ficrosclera are not present.

This species is interesting in a certain respect; it resembles to a very high degree one of the
species with chelz, viz. 7. stylata; the only differences, besides the want of the chele, are that both
the styli and the dermal spicules are slightly smaller in the present species than in s¢ylata, but this
is of no specific value; otherwise the growth, the surface with its papille, the structure of the dermal
membrane, the arrangement of the skeleton and the shape of both kinds of spicules agree very well in
the two species, and if it were not for the difference in the possession and non-possession of chele,
and the difference in the structure of the dermal membrane, to which the want of the chele seems
to give rise, I should not hesitate in uniting them. As however I have otherwise never found, that
the same species may be with or without chele, I think it necessary to consider the present species
as specifically distinct from 7. stylata.*) It is to be remarked, that the specimens of both species are

1) To be sure Topsent has described (Résultats du Voy. du S. Y. Belgica, Spongiaires, 1901, 18.) a species without
sigmata as Lissodendoryx spongiosa R. and D. var. asigmata, and in the same place the author strongly advocates the view that
sponge-species are capable of varying in such a way, that they may want a form of microsclera otherwise present in the
species; I cannot at all agree with Topsent in this view, and with regard to the examples he mentions (Hamacantha John-
soni, Desmaceila Peachii) 1 have proved (The Ingolf Exp. VI, 1. 1902) that the supposed varieties are distinct species, and with
regard to H. Johnsoni Topsent has himself in his work from 1904 admitted the specific validity of his former varieties.

PORIFERA. III. 109

in a good state, and they have especially the dermal membrane undamaged, and further it must be
noted, that the chelz in s¢y/a/a are numerous and form a layer in the dermal membrane. Should the
two species be considered as identical, it must be from the point of view, that the specimens of
dermata were abnormal, but there is otherwise nothing to indicate such a state. Now one fact is
very interesting, and it is that H sty/ata is from the cold area (station 113, bottom temperature
+1°0C), while the present species is from bottom with positive temperature. It is not for the first
time that very nearly related, but distinct species are found one on negative the other on positive
bottom (e. g. Gelliodes plexa and consimilis, The Danish Ingolf Exp. VI, 1; Asdestopluma pennatula and
bihamatifera, Cladorhiza abyssicola and gelida, Lissodendoryx complicata and vicina, ibid. VI, 2.).

| Locality: Station 2, 63°04! Lat.N., 9° 22' Long. W., depth 262 fathoms; Forsblads Fjord in
East Greenland, depth 50—g0 fathoms (The Amdrup Expedition 1900). The localities lie at East
Greenland and West of the Farée Islands.

50. H. tornotata n. sp.
Pl. III, Fig. 18, Pl. XI, Fig. 2.

Incrusting; surface hispid. Spicula: megasclera; the skeletal spicules acanthostyli with a more
or less pronounced head, entirely spined but in the longer the spines very small outwards, o-107—0°31”",
not distinctly divided into two groups; the dermal spicules long tornota, generally with microspined

end-parts, o-32—0'47"". No microsclera.

This species is represented by four specimens, three growing on shell-fragments, the fourth on
a Brachiopod; the former are rather small crusts while the latter covers the greatest part of the
Brachiopod shell and has thus an extent of 20". The small specimens are about o7™" thick while
the larger one reaches to a thickness of about 1™™; this comparatively great thickness is reached on
account of a special development of the dermal skeleton as mentioned below. The colour (in spirit)
is light brown to brown. The swzface is densely hispid from projecting dermal spicules; the small
specimens are much more hispid than the large. The dermal membrane is inconspicuous and not
separable. Oscula and pores were not observed.

The skeleton. The dermal skeleton consists of large bundles of dermal spicules which stretch
from the main skeleton to the surface, the spicules in the bundles are penicillately spread outwards
and project beyond the surface for a rather long distance; seen from above the projecting spicules
are almost stellately arranged. Such is the construction of the dermal skeleton in the small specimens,
but in the large specimen the facts are somewhat otherwise; the dermal spicules are here more numerous
and they are somewhat strongly interwoven, forming a dense and thick layer, and apparently lying
without any order; only outermost they are arranged somewhat parallel, with the points projecting
outwards; this layer may reach to a thickness of o8™™. The difference in the development of the
dermal skeleton in this species is, as will be seen, about the same as may also occur in . Dujardinit.
The main skeleton is of typical construction, consisting of vertical acanthostyli with the heads on the

substratum; they are placed rather densely. At the base there is an amount of spongin,

110 PORIFERA. III.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are not divided
into two groups, in so far as intermediate forms occur, but as these are somewhat rare, the styli give
the impression of falling into two groups; the large styli are straight or very slightly curved, they
have a roundish head with moderately sized spines, the shaft has small spines which become quite
gritty outwards; the small styli are generally straight, the head is less pronounced than in the large,
the spines are larger and often distinctly reclined. The length of the styli is in all o107—o0'31™ and
the diameter at the head oor4—o021™, 2. The dermal spicules are long, straight, or somewhat,
often irregularly, curved tornota; they are thickest in the middle and thus more or less fusiform; they
show a curious feature, the end-parts being generally, but not always, somewhat roughened or micro-
spined. The length is 032—047™" and the diameter in the middle o004—0007™. Jicrosclera are
not present. i

Locality: Station 81, 61° 44' Lat.N., 27° oo' Long. W., depth 485 fathoms; station 89, 64° 45' Lat. N.,
27° 20' Long. W., depth 310 fathoms; East of the Farée Islands, depth 160 fathoms. The localities lie
in the Denmark Strait, South-west of Iceland and at the Farée Islands.

51. H. mucronella n. sp.
Pl. III, Fig. 19, Pl. XI, Fig. 3.

Incrusting, but of somewhat massive appearance; surface hispid. The dermal skeleton strongly
developed, the main skeleton weak. Spicula: megasclera; the skeletal spicules acanthostyli divided into
two groups, large with a very small head, only spined below, o4o—065"", small, with a more distinct
head, and entirely spined, o'14g—o'178"™ ; the dermal spicules tornota with one end with a mucro, o-38—

o596"", No mtcrosclera.

Of this species we have only one specimen which grows on a fragment of a S7ho; the sponge
is of a somewhat massive shape as it does not incrust the shell-fragment but is only fixed on it and
is for the rest somewhat filled with bottom material; it thus shows a growth similar to that in W. grandis,
though it is much less filled with foreign particles. On account of large cavities in the sponge the
consistency is somewhat bladder-like. The specimen has an extent of 17™ and a height of about
g™™. The colour (in spirit) is dark greyish brown. The surface is strongly and densely hispid from
projecting dermal spicules. Oscuda and pores were not observed.

The skeleton. The dermal skeleton; the skeleton formed of the dermal spicules is strongly
developed and occupies the greatest part of the sponge; it consists of fibres running everywhere but
chiefly in the direction from the base, or else from some part of the main skeleton, towards the
surface, the fibres may thus attain a relatively great length; in the dermal membrane the spicules
form penicillately spread bundles, the spicules of which pierce the membrane; seen from above the
spicules in the bundles appear almost stellately arranged; in places where the membrane stretches
over the large cavities, fibres pass horizontally just below it, and the bundles seem here to originate
from these fibres. The sponge-body has, as said, many large cavities and the fibres are found
therefore in the parts of the tissue separating these cavities. The man skeleton is not much
. developed; it consists of acanthostyli based with their heads partly on the shell at the base of the

PORIFERA. III. III

sponge and partly on the imbedded foreign particles, such as large sponge-spicules, gravel and the like,
which particles must be considered therefore also as substratum for the sponge; the acanthostyli
placed on the imbedded material may point in every direction, and the main skeleton is, according to
the manner of growth of the sponge, quite irregular. At the head of each acanthostyle there is a
small, but distinctly observable amount of spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli, divided into two groups,
large and small; the large styli are straight or slightly curved near the base; the head is very small
or almost quite absent, the basal part has some small or moderately sized spines, but only for a
short distance, the remainder of the shaft being smooth or slightly and imperceptibly gritty. The
length is o4o—o65™™ and the diameter at the base oor7—oo21™. The small acanthostyli are
generally straight with a slight but distinct head-swelling; they are densely spined in the whole
length, the spines on the head being the largest. The length is o14—o178™" and the diameter of
the head is oo17™", 2. The dermal spicules are tornota but of a characteristic shape; one end is
pointed in the way common for tornota and not very short, the other end is shorter and more roundish
pointed and has a very distinct mucro; the latter end is somewhat thicker than the former; the
tornota are long, straight or nearly so and slightly thicker in the middle than towards the ends.
The length is 0:°38—o'596™" and the diameter in the middle o'1005—o011™"; the intermediate sizes are
by far the most common. J“crosclera are not present.

Locality: At East Greenland, 70° 32’ Lat. N., 8° 10’ Long. W., depth 470 fathoms (The Ryder
Expedition 1891—92).

Above I have described 51 species of Hymedesmia of which only seven are determined as
previously described species; these are: A. Kochleri Tops., occulta Bow., baculifera Tops. crux O. Schmidt,
Jilifera O. Schmidt, mucronata Tops., and Dwyardinii Bow. I have tried to find out the other previously
described species, and I think that at all events most of them are enumerated in the following list:

1866, H, zetlandica Bow. Mon. Brit. Spong. II, 152, III, Pl. XXI. figs. 1—7.
« — paupertas Bow. ibid., II, 223, III, Pl. XXXV, fig. 4—8 (Hymeniacidon).
1875. — vidua O. Schmidt. Jahresber. der Comm. zur wissensch. Unters. der deutsch. Meere in Kiel fiir
1872—73, 120. (Sfirastrella); Thiele, Arch. fiir Naturgesch. 1903, I, 393, Taf. XXI, Fig. 27.
1882. — Peachit Bow. 1. c. IV, 64. Pl. XIII, figs. 5—12.
1885. — mammiilaris Frstdt. Kg]. Sv. Vetensk. Akad. Handl. 21, 6, 32, Tav. III, Fig. 3a—h. (Hastatus);
Thiele, Arch. fiir Naturgesch. 1903, I, 389, Taf. XXI, Fig. 22 a—d.
1887. — pustula Frstdt. Ofvers. Kgl. Vet. Akad. Férh. 1887, No. 1, 27, (Zsperia).
1903. — prostraia Thiele, Abhandl. Senckenb. nat. Gesell. XXV, 955, Taf. XXVIII, Fig. 20.
« -— norvegica Thiele, Arch. fiir Naturgesch. 1903, I, 390, Taf. XXI, Fig. 23 a—c. (perhaps a Stylostichon).
1904. — mutabilis Tops. Résultats des camp. scient. du Prince de Monaco, Fasc. XXV, 166, Pl. XIV,
fig. 3. (Hymeraphia).
« — Schmidti Tops. ibid., 189, Pl. XV, fig. 9. (Lepsosia).

112 PORIFERA. | III.

1904. H. raphigena Tops. Résultats des camp. scient. du Prince de Monaco, Fasc. XXV, 192, Pl. XV,
fig. 7. (Leptosia). :
« — obtusata Tops. ibid. 193, Pl XV, fig. 6. (Zepzosza).
« — acerata Tops. ibid., 193, Pl. XV, fig. 5. (Zepéosia).
1905. — fenuissima Dendy, Rep. on the Pearl Oyster Fishery of the Gulf of Manaar, III, 169, Pl. XI,
fig. 5. (AZyxilla).
« — areolata Thiele, Zool. Jahrb. 1905, 452, Taf. 31, Fig. 23, 68 a—d.
1906. — Jancifera Tops. Bull. du Mus. @hist. nat. 560. (Lepéosza).

The number of species seems thus at present to be about seventy; this is already a large
number and there is reason to believe, that many more species will be described in the future.
Earlier Expeditions paid often but little attention to the insignificant crusts, which is the shape of
most Hymedesmia species; it is first in the work of Topsent from 1904 that a greater number of
incrusting species of various genera is recorded, and the author says expressly, that this fact is due
to the care with which he examined stones, corals etc. brought home. The Ingolf Expedition laid
the greatest stress on procuring all small and incrusting sponges, and hence our material is very rich.
Under these circumstances when the number of species must be expected to increase in the future
to some degree, it is of the greatest importance, that the new species are described thoroughly, and
the spicules ought always to be figured, so that the affinities of the species can be judged. I shall
therefore try to give here an analytical table of all the above enumerated species; this table is of
course only an attempt, and I do not think that a species can be definitely determined only by its
aid, but I think however it may be useful. ,

Table of the Species of Hymedesmia.

1. Microsclera ‘present :..... ,{. vsti «:s,s:kuig's oped « goannas Ween ee Re ole mace pass 2.

<= No Miicroscletar? s.2 3.2 5.,57recs Scajatwasiecs inlsce’ dose sein Slater eae erento ore tater onset edge 59.

2. Microsclera only chelz arcuate (sometimes transformed to spined rods)........ 3.
— Microsclera chele arcuate together with sigmata, or sigmata alone or rhaphides 45-

3. The chele of common shape: sj: wives Kec nee sons FP ages! ube apne onet 4.

—-. The chele spined or quite, transformed . . <p ones hye cess oe cee + eee ne 43-

4: The detmal spicules genuine strongyla’. 60% cis. (ili ride ce eves bie nb soemieaes 5

— The dermal spicules of other forms, at all events not quite genuine strongyla. ai.

5. The acanthostyli not divided into two groupsS........... 66. ccccee cece ee eenees 6.

— The acanthostyli somewhat distinctly divided into two groups................ 13.

6. The dermal strongyla more or less distinctly polytylote ...................45- Js

— The dermal strongyla not, or not distinctly, polytylote ..............++e0.+0-- IO. 2
7. The chelz somewhat strongly curved, o1028—ooso™, the acanthostyli with blunt

spines on_ the headh. .. 4.00.05 spies ss 55,5495 ne ss CRUE 6 awa Seville one ana Ee Koehleri Tops.

— The chele less strotigly curved oo... 0... eens os cay e cubes) «ese sietlenie cies Bien

8. The chelz with somewhat long, free ala, 0°045—0'054™......--.eeceeeeeeeeee lacera

— The chele smaller, somewhat like palmate chele ...........0..0.02220000euees 9.

g. The acanthostyli strongly spined, especially at the head, chelz 0:°033—0:038™. storea
— The acanthostyli less strongly spined, chelze 0'028™ ......... 0... cece eee ee eeee lamina

PORIFERA. III.

113
To. Suriace: with low iwarts orilongpapillee .. a: 22a. ARG prey - II.
at SRW CMT hy Jada avd rei sour ocak vere Fee dse rege bees .osneupene feeb 12.
11. Surface with low warts, dermal strongyla long and straight .................. VErTUCOSA
— Surface with long papille, dermal strongyla robust with a double curvature... ljfera Schmidt.
12. The acanthostyli only spined on the head ............ cece eb ec eee ence ees norvegica ‘Thiele.
— The acanthostyli spined in the lower half part............ 0.0. cece cece scenes mollis
13. The chelz strongly, nearly semicircularly curved.............. 26. e cess eee curvichela
ae ee ee thes STOREY CRT VEd rs ie. 5S. 6 eS. Oo a ieee DONT EROO 14.
14. The dermal spicules polytylote, chelz large, 01052—0'064™", the end-parts some-
IE 20 SPELT rugosa
— The dermal spicules not polytylote, chele smaller.............. 0.00. e ee eeee 15.
15. The acanthostyli strongly spined in the whole length....................+-5. splenium
=— tne meanthostyli not entirely spined (200.05... f6650 i Pe bk baie ee 16.
16. The large acanthostyli spined towards the apex, chelz 0'032—0:037"", the free
part of the shaft about one third of the length ............... cee cece eee eee tenutcula
— The large acanthostyli at most spined in the lower half part................. 17.
17. The small acanthostyli distinctly curved ........... 06.6 ce ence nett eee eens 18.
ee tee ee SEP ONOMtORtY! .Atraleht. i ee io os FR GUT ye os d ble Lada. 19.
18. The acanthostyli reaching to065™", chelze somewhat strongly curved,0035—o'044™" = szmilis
— The acanthostyli reaching to o'42™™, chelz less curved, 0°:037™......-.-.+.005 paupertas Bow.
19. The acanthostyli long, reaching to o795™, the dermal spicules slightly tending
POmaT ae CEDIA ener iene Uy DM nd Cn ates Ramee eset lend aiee ae nummulus
— The acanthostyli shorter, the dermal spicules pure strongyla.................. 20.
20. The acanthostyli reaching to 063™", the dermal strongyla 0-35—0'52™", surface
NONE A wie us iistic vam forws ois aan Svea anes aa eS nng sad ols LROOTANs | stylata
— The acanthostyli reaching to 0'38™", the dermal strongyla o026—o'32™", surface
NM a Pl Ph Gras ge CN Wega Wes ccs c alg aig vies ee TW Gaul d oWTab eMunye ld dubia
21. The dermal spicules diactinal (at all events not distinctly monactinal)......... 22
an eae MRD epnemnemmOnACtiNal 2505.35 6 iid aa aati es «be aiie ied pee Soles cla ele nets ee 42.
Pee rene NII NUNES COUMIQUG a alas a ee i es a a ee cece n ees 23.
Se mermenh epeetien Ome Or tylotal® ii:éciais dee Roi aces) Vewsiiee adidas lies 32.
23. The dermal spicules centrotylote: tormota..).)5).36:. ieee eiiea ss ene paw ee be des lancifera ‘Tops.
PP He v@ermualsniCties NOt CEMILOCVIOLE! Wiss iieie cs is vies Gees vey Veeles os gs oalleee ee 24.
a4) Tme tommota with! uhequalienday?.o)i7 bolieih.ivinedsues sais weiledaded.san.i 25:
See, ene MUM TERL @QUST CUE iy ry iG gh k Nica sew ivein ep Cua ten ecaneraneaseetes 26.
25. The large acanthostyli only spined at the base, O24 ™™ ‘chelge'Q:01r8 Ps vfs ids prostrata Thiele.
— The large acanthostyli a little more spined, 045™™, chelee 0103™.............- Peachit Bow.
7 large acanthostyli spined in about the whole length..................4.. 27.
— The 3i.
27. The chelz of ordi 28.
— The chele extraorditiari platychela
28. Surface with papillz, torttota 0:36™, chelee 0°:024™......... 00sec cece eee eeees mammillaris Frstdt.
— Surface simple............. Nea Gras REMNEA RES CRMGLS CK5 45 MoKA RCE SONY 5. 4STRO 29.
29. The acanthostyli reaching to 0553 mm, the tornota o'17-—-0'22™", chelze with slightly
recurved end-parts o07021—0'054"" Cee Seago SA reer yy cree ce eee perforata
— The acanthostyli not reaching Over 0°35™ ©... ec isees ces cuee ween tense eweanes 30.
The Ingolf-Expedition. VI. 3 15
\
\
t \

\

114 PORIFERA. III

30. The acanthostyli reaching to 0:35™™, tornota 0'22—0'32™", chelze somewhat strongly

Cr ved -DURG——O05G 88 oo is voi dic ae os vow bninnn od CERERE ee nee eee oe eee
— The acanthostyli reaching to 0:298™", tornota o'16—o'17™", chelze less strongly

etirved, OO4T—QOSAME EDI 6 Fae NN WE Game ctw STE teats genie ote
31. Surface with papilla, acanthostyli reaching to o'59™", tornota 0°32—o'50™", chelze

somewhat palmate-like, 01025—O030% ....---eeci cece dsneendeertaacteswsinnes
— Surface simple, acanthostyli reaching to o'92™, tornota 0:23—0'28™", chelz of

ordinary Shape, 0025—O045™ 2.0.22... 05 ccs cena erga ceeee aes sen cnion RAleulenns
32. Dermal spiculesoxea 2)... U 2 0 ee es ST RGR OERK (SUN EIS ale
— Dermal sepisiles tylota. «6... ocgceee cos eons cpivw int rmgne Seno ad tee he we eee
33. The acanthostyli almost entirely spined, chela 0'025™ ............e esse eee ee
— The acanthostyli only spined near the base.:.........0.. ccc cece eee eee eens
34. The acanthostyli reaching to r1g™™, chelz 0:034—O040™ .........00-2 ese eee
— The acanthostyli reaching to 065™", chele strongly curved, 0'°028—0'037™ ....
35. The acanthostyli almost smooth, only slightly spined at the base, chelz 0045

— The acanthostyli-more spined, often entirely ............ 2. ccc cee ee eet eenee
36. The acanthostyli divided into two groupS..........-.see eset eee eee eee ee eeee
— The acanthostyli not divided into two groups............. ee eee eee eee eee eee
37. The acanthostyli varying in size, reaching to o'25™............ iD. Ra
— The acanthostyli rather uniform in size, not reaching over O'13™ ............
38. The acanthostyli somewhat robustly spined, dermal tylota not or only slightly

polytylote 2.0... chews ole enn arate Gag GR Sed Peale bla eee a eee aie me a
— The acanthostyli more finely spined, dermal tylota polytylote.................
39. The acanthostyli truncate at the point........ ea diccs diac CAS Oe
— The acanthostyli not truncate at the point ............ 0... eee eee eee eens
40. The tylota distinctly polytylote, O148™... 2... cece e eee eee ee eee e eee ees eeees
— The tylota not, or not conspicuously polytylote, length or19™™ or more........
41. The acanthostyli without any neck-shaped constriction at the base, the tylota

re Cs tae OF, bea A a yeaa ce OE ee
— The acanthostyli with aneck-shaped constriction at the base, the tylota o.30—o'40™
42. The dermal styli polytylote, the acanthostyli not divided into two groups,’ chelz

POJO— TOGO nnn. nsec cuneate a uidia up sign wane 0 ey ARMM VERE Do MME ARNE
— The dermal styli not polytylote, the acanthostyli divided into two groups, chelz

CDRS one none o wit civ vrgleegeldie Da ossir nrey. erie aR NW 6 6 x. Ee Oe a
43. The chelz transformed to spined rodS.... 0.0. es eee a en eae
— The chelz less transformed, more chel-shaped, or only spined.......-........
44. The chelee of normal shape but spined ........... 00 cece ee ec cece eee eee eees
— The chelz more transformed, somewhat asteriform...................2000005-
45, Microsclera chelz and sigmata.... ie -ci ices. ee cc oreenveceresys +4 Dieu muenlen
— Among the microsclera no chel@.....- 0. ec ce ce svn nes © fb ae Cee eenien
46; Sigmata only-of one forii.:..2 606s. bee cs WATS De Hil ee Oe DOTS . Delaee
— Sigmatel two forms. oo. 6c Chee cb re on ccns wy conse eens Di eme asen ear
47. The acanthostyli of uniform size, about o13™™, strongly spined, sigmata in

DUNG os lsh cin vce a 05d avin nib mck 6 epi ns /Dialu 8 5 5(dsa: Slag ete Soca EN ERE sare
— The acanthostyli longer, sigmata not in bundles ............6.. 0. cece ee eens

procumbens
clavigera
basispinosa

longistylus
33-
35:
areolata Thiele.
34
occulta Bow.
simillima

levistylus
36.

bractea.
37:
38.
39-

baculifera Tops.
levis
truncata

40.
tenutssima Dend.

AI.

Bowerbanki
latrunculiotdes

trregularis

proxima
vidua Schmidt.
44-
crux Schmidt.
aenigma
46.
58.
47-
56.

zetlandica Bow.
48.

PORIFERA. III. II5

46. The chelcesapined and transformed): . 2... de a ae Schmidti Tops.
a a I OT NNN gaia fin aslo GE Ak mids ess x Figs o Aig ed vive Kis plele hike aa ohh 49.
49. The chelze of two forms, ordinary and peculiar................ 0. cece cee e eae mucronata ‘Tops.
en MRE CR OE MO iia kg wre ee dn a Bae Se Cag mace hee oy oon pve he Dey ae 50.
50. Sigmata rather large, not below o028™™ and generally much larger, surface
gi ich es oR as ca eS Ss ari e2 e ELE 5I.
~- Sigmata small, not above o7020™, surface simple..................... 002 eee 54-
51. Surface with warts, sigmata about o1r™™, chele of two forms, large o025™",
OT Eh ely lA ae ha Bile S169 5 Ste ian oa ts Fat Sea eee PR ke 2 er er A A ee Pa pustula Frstdt.
— Surface with long, cylindrical papillz, chelze of one form.........../......-4. 52.
52. Sigmata nearly plane, dermal tylota o'29g—0'38™", sigmata o7058—0'075™...... trichoma
ld aE ns des cig cole an wo gia nS e833, 9,45 tre. magnce ne tay 53:

53. The acanthostyli o4t—0'75™", dermal tylota o.48—o'80™, sigmata 07031—o'096™" = grandis
— The acanthostyli o11—o'31™", dermal tylota o-26—o-41™", sigmata 0'028—o'050™" digitata
54. The dermal spicules thin styli, sigmata circularly curved, nearly plane,oorg—oror7™" fugio

eee eee eee Meee MOU Style ss. 5. 5 2 hee 55.
55- The dermal spicules tornota o15—o'19™, sigmata O'OI4—O'OI7™ ..........006. consanguinea
— The dermal spicules tylota 0o:23—0'28™, sigmata O'020™........ 0.000 e eens mutabilis Tops.
56. The large sigmata somewhat band-shaped, peculiarly curved, the smallsigmata plane czdtrisigma
— Both the large and small sigmata of ordinary shape .................02e0000: 57:
57. The large sigmata o-18—0:208™, the small o106—o089™.. 2.0.66. eee eee eee macrosigma
— The large sigmata contorted, o021—0028"", the small sigmata plane o014™".. planca
ee Mg See tens Na us gece Rs he oie Se Lee 1. E Re tenuisigma
eee RMNEN RIMMMIMNENSS , WR TU acs ce esos ews edb oboe Fae ee bevdee swabs rhaphigena Tops.
earerian eracuies Stroneyia Or. tylotarres 5 1. oy oes cbse ease ce epee saeco onces 60.
RE NIN NMI 5 cae ons eh a aid indies xR vm IRA oo «8 015 ho mine 005.9 wg be wi 65.
nme meamanostyl truncate at the point . 2... 1... cee enc en tee ener e eee obtusata Tops.
— The acanthostyli not truncate at the point............... 0. ccc ccc e eee eee 61.
61. The acanthostyli generally with a globular head, 01083—0'22™, the dermal spicules

strongyla to subtylota and there are always subtylota present ................ Dujardinii Bow.
Pe ter CIE SUOMOE VIR iis). Ge bwiis oie sie. a scivies Switailoie.oieiesle ciel wave ees 62.
62. The acanthostyli not divided into two groups ................. cece eee ee eeee 63.
— The acanthostyli divided into two groups, the dermal spicules long, 0°33—045"" dermata
ee tame REA GEV IR TIERPOLY UMUC iano Win ois hy. Fes OR ne vies os acts e PHagys Vos eae ees aequata
— The acanthostyli with a smooth apical part................. cece cece e eee ees 64.
64. The acanthostyli o11—0'35™", dermal strongyla polytylote, o149—o'28™ ...... primitiva
— Theacanthostyli o10o—o'50™", dermal strongyla smooth or polytylote, 0:22—0'298 mm Jongurius
65. The dermal tornota not polytylote, generally microspined at the end-parts.... ‘ornotata
= eee cereal tornota not with spined ends... oo 0S oc or eccde ccs eutesteecteces 66.
66. The acanthostyli o1r4—0'38™", the tornota slightly polytylote ................. acerata Tops.
— The acanthostyli o14—065™", divided into two groups, the tornota with a mucro

ee BG sw Sehes wa Ale dee ew eds pee Oa SAA Rees Gea ede ds Goes wel mucronella

Four species in Bowerbank’s Monograph could perhaps also be taken into consideration, viz.
Hymentactdon perarmatus (III, Pl. XXXI, figs. 11—16) which would in such a case perhaps be related to
H. occulta and simillima; but it is possible that the species is an Zctyodoryx. Hymedesmia pansa

15*

116 PORIFERA. III.

(IV, Pl. I, figs. 1—4) has long, monactinal dermal spicules; it seems to be a Hymedesmia or an Eurypon.
Hymedesmia pilata (1V, 59, Pl. II, figs. 1-4), which seems to have no dermal spicules and only sigmata
for microsclera, is I think an Eurypon. Finally Hymedesmia pulchella (IV, 61, Pl. I, figs. 5—8) seems
to be likewise an Euryfon.

Flymeniacidon paupertas Bow. (III, Pl. XX XVII, figs. 4—8) I have included in the above table
as I take it to be a Hymedesmia, and I think the Myxilla paupertas recorded by Topsent (1904,
Fasc. XXV, 168) is another species. The Hymedesmia areolata Thiele mentioned by Kirkpatrick
(Nat. Antarc. Exp. Nat. Hist. IV, Pl. 22, figs. 3-3) cannot I think be a Hymedesmia and must
accordingly be another species. Thiele (Abhandl. Senckenb. nat. Gesell. XXV, 1903, 955) thinks that
Myxilla veneta O. Schmidt is identical with fasciculata \ieberk., and is a Hymedesmia; I have examined
a specimen of J/yxilla fasciculata send from Professor von Marenzeller; it is correct that the species
incrusts the chitinuous tubes of Stephanoscyphus, but it has otherwise a reticulate skeleton and is no
Flymedesmia; M. veneta 1 do not know. Hymedesmia norvegica Thiele, which I have included in the
above table, is perhaps not a Hymedesmia as it has short skeleton columns; it would thus be a
Stylostichon.

Hymenancora n. g.

Incrusting, thin forms. The external appearance, the skeleton and the megasclera quite as in
Flymedesmia; the microsclera are ancore which may be either ancore spatulifere or unguifere; some-

times two forms of ancore occur; to the ancore sigmata are sometimes added.

In the introduction to the second part of this work I have, in accordance with the opinions
of Levinsen, advanced the view, that species with ancorz and species with chelz should not remain
in the same genus, and in accordance herewith I emended the genera Desmacidon and Homoeodictya,
Myxilla and Lissodendoryx, and according to the same view I have created the genera Ectyodoryx
and Lctyomyxilla (Meddel. om Gronland, XXIX, 1909, 444), the first with chelze, the latter with ancore.
Also the genus Hymedesmia has hitherto included species with chelz and species with ancorze, and it
is to comprise these latter species that I create the genus /ymenancora which is in all other respects
similar to Hymedesmia.

So far as I am avare the genus comprises at present the following species:

1892. H. Pecqueryi Tops. Résultats des camp. scient. du Prince de Monaco, Fasc. II, 110, Pl. XI, fig. 8
(Myxilla).
« H. minima Tops. ibid. 114, Pl. XI, fig. 2—3. (Hymeraphia).
1904. 7. biscutella Tops. ibid., Fasc. XXV, 191, Pl. XV, fig. 3. (Zepéosza).
« H.umbellifera Tops. ibid. 192, Pl. XV, fig. 4. (Leptosia).
1905. Z7. laevis Thiele, Zool. Jahrbiicher, 1905, 453, Taf. 31, Fig. 69 a—f. (Hymedesmza).
« #1. tenuissima Thiele, ibid. 454, Taf. 31, Fig. 7oa—f. (Hymedesmia).
1907. H. exigua Kirkpatr. Ann. Mag. Nat. Hist. 7, XX, 273, and 1909, Nat. Antarct. Exp. IV, Pl. XXII,
fig. 4, Pl. XXVI, figs. 2a—f. (Wymedesmia).

PORIFERA. III. 117

1907. 7. rufa Kirkpatr. Ann. Mag. Nat. Hist. 7, XX, 274, and 1909, Nat. Antarct. Exp. IV, Pl. XXII,
fig. 5, Pl. X XVI, figs. 3a—e. (Hymeraphia).
H. interjecta mihi
FT. conjungens mihi .
HT. tenutsclera mihi
Hi. dupilicata mihi.

I do not see the slightest reason why A. minima Tops. and H. rufa Kirkpatr., both placed by
the authors in Hymeraphia, should not belong to Hymenancora.

1. H. interjecta n. sp.
Pl. XI, Fig. 4.

Incrusting; surface slightly hispid. Spicula: megasclera; the skeletal spicules acanthostyli without
a real head-swelling, spined in the whole length, they are divided into two groups, large o.37—0'47"",
small o'1g4—o'16"",; the dermal spicules tylota or subtylota o-30—0:47”"; microsclera two forms, ancore

spatulifera with three teeth, o-025—o'045”", sigmata o'06—o0'128"™,

Of this species we have two specimens; one grows on a dead branch of an Oculina together
with 7. procumbens and specimens of Zedania, Eurypon and Latrunculia; the other specimen, which
is very small, grows on a pebble. The largest specimen is extended along the Ocudiza-branch and is
therefore of a lengthy shape and has a greatest extent of 22™"; it is exceedingly thin. The colour
(in spirit) is greyish or brownish. The surface is in the present state of the sponge slightly hispid.
About the dermal membrane, pores and oscula I can say nothing.

The skeleton. The dermal skeleton seems to consist of bundles and scattered spicules. The
main skeleton is, so far as I could observe, constructed in the ordinary way of vertical acanthostyli
piaced on the substratum, but the styli are somewhat scattered and the dermal skeleton is therefore
the most developed part of the whole skeleton.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are somewhat
distinctly divided into two groups. The large styli are straight or generally somewhat curved near
the base; the base is a little thickened, but there is no head-swelling present, and they taper into a
long and fine apex; the styli are spined in their whole length, but the spines are only at the base
of larger size, they decrease in size outwards, and the shaft and apex are only gritty; the larger
spines at the base are generally curved upwards in a somewhat characteristic way. The small styli
are principally of the same shape as the large, but they are often straight, and the spines are relatively
larger, the head also is still less developed than in the large. The length of the large styli is 037—
047™" with a diameter at the base of o1020—0:023™". The small styli have a length of o14—o16™
and a diameter at the base of o'1020™". 2. The dermal spicules may best be termed tylota; they
are straight or very slightly curved and somewhat robust, the end-swellings are very small but how-
ever always perceptible. The length is o30—o047™", and the diameter of the shaft o007—oo010™.
b. Microsclera are of two forms, ancorz spatuliferze and sigmata. 1. The ancore have a curved shaft
and three elliptical teeth at each end, but the most remarkable feature is, that they have only very

118 PORIFERA. III.

narrow ale or these may be quite absent; by this fact these ancore get some resemblance to arcuate
chelze and it seems that they also in reality must be nearly related to these. The length of the
ancore varies much, it is oo25—0'045™", and the thickness of the shaft is about 0'7002—0'005™™".. 2, The
sigmata are of ordinary shape and more or less contorted; they have a length of oo6—o'128"™ and a
thickness of o:004—0'0065"™". The microsclera seem to occur through the whole tissue.

Locality: Station 54, South of Iceland, 63° 08’ Lat. N., 15° 40’ Long. W., depth 691 fathoms;
station 98, in the Denmark Strait, 65° 38’ Lat. N., 26° 27’ Long. W., depth 138 fathoms.

Remarks: As said the ancore in this species seem to be nearly related to the chele arcuate
on account of the very narrow and, so far as I could see, sometimes quite wanting alee, but they are
however true ancore. In Part II of this work p.3 I have stated that I consider the ancore and
chelz arcuate as nearly related spicula and as having been derived from a common original form of
spicule. It is well known, that the chelz arcuate may be more or less ancora-like, but being at the
same time true chelz, and many examples of this are given in the preceding descriptions. As one
of the most ancora-like chele I have examined I may note the chela in Hymedesmia Bowerbanki.
The ale do not go here evenly over into the hinder side of the shaft but are somewhat incurved at
the shaft, so that in a side view the “tuberculum” is seen quite surrounded by the outer contour of
the ala; and so far as I could see the shaft is a little edge-like dilated towards the ends; these
spicules are however true chele. Should there be found in the genus Hymedesmia forms of micro-
sclera which were intermediate between ancorze and chelz arcuate, and this seems not impossible, it
would be of great interest, and it would seem to indicate at the same time, that Mymedesmia is a
genus of old origin, as already alluded to from other reasons under H. aenigma,

2. H. conjungens n. sp.
Pl. XI, Fig. 5.

Incrusting; surface somewhat hispid. Spicula: megasclera; the skeletal spicules acanthostyli
without head-swelling, they are divided into two groups, large, spined nearly in the whole length or
only with a small apical part smooth, o-29—041"", small, entirely spined, o1r—o'rgmm ; the dermal
spicules tylota with pointed end-swellings, 016—o 22"; microsclera two forms, ancore spatulifere with

three teeth, 0:022—0'042™", sigmata 0'035—0'045"™.

We have one specimen of this species growing on a living Pecten together with specimens of
Melonanchora emphysema, Hymedesmia perforata and procumbens, a Crella, an Eurypon and a Plocamia.
It forms an incrustation of an extent of about 15™™, and it is very thin, not reaching o5™. The
colour (in spirit) is light brownish grey. The sazface is somewhat hispid from projecting spicules. The
dermal membrane is a thin, transparent film, resting on the skeleton below. Oscuda and pores: larger
and smaller, simple circular openings are seen in the dermal. membrane representing I think both
oscula and pores.

The skeleton. The dermal skeleton consists of bundles of dermal spicules stretching up to the
dermal membrane and supporting it, the spicules in the bundles being somewhat penicillately spread

outwards; the bundles are generally not large, consisting only of relatively few spicules, There are

PORIFERA. III. 119

no horizontal spicules in the membrane itself. The main skeleton is constructed as usual of acantho-
styli with their heads placed on the shell, the longest of them reach to the dermal membrane and
project beyond it. At the base there is a small amount of spongin.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are divided into two
groups, large and small; the large styli are generally slightly curved, they are a little thickened at
the base, but there is no head-swelling, they taper only slightly outwards and the point is somewhat
short; the styli are spined in almost the whole length, only a small part of the apex being smooth or
nearly smooth; at the base the spines are of medium size and numerous, outwards they are small,
nearly gritty, and more scattered. The small styli are mainly of the same shape asthe large, they
are straight or slightly curved and have likewise no head-swelling, but they are spined in the whole
length. The length of the large styli is o29g—o'41™" with a thickness at the base of oo16—o021™™,
the small styli are o1r1—o'13™" long with a diameter at the base of oor1—oo014™. 2. The dermal
spicules are tylota with the swollen ends pointed like tornotes; the shaft is slender and generally
straight, sometimes it is very slightly polytylote; the ends are distinctly but not much swollen, and
they are pointed in such a way that the spicule might be termed a tornote were it not for the
swellings. The length is o16—o'22™", and the diameter of the shaft is o0028—o004™. b. Aficrosclera
are of two forms, ancoree spatuliferee and sigmata. 1. The ancorz resemble those in zuferjecta, but
they are a little less curved or the curve is distinctly localized in the middle of the shaft; they have
three elliptical teeth at each end, the ale are not large but distinct and always present. This ancora
is thus evidently related to that in zz¢erjecta, but it is less chel-like. The length is o022—o042™
and the thickness of the shaft is o(002—0'004™"; the large aucorze are by far the most numerous while
the smaller are seen only rarely. 2. The sigmata are of ordinary shape and they are contorted,
generally a quarter of a turn. The length is 0035—o045™" and the thickness about o'0028™™. The
sigmata occur in the tissue of the sponge but not in the dermal membrane, the ancorz occur also in
the tissue but especially in the dermal membrane and here rather numerously.

This and the preceding species are nearly related, but they are characteristically different in
the shape of the dermal spicules, the size of the sigmata and also in the shape of the ancore.

Locality: South of Iceland, 63° 21' Lat.N., 16° 22’ Long. W., depth 296 fathoms (The Fishery

investigation steamer “Thor”).

3. H. duplicata n. sp.
Pl. XI, Fig. 6.

Incrusting; surface hispid? Spicula: megasclera; the skeletal spicules acanthostyli with a small
but distinct head-swelling, the largest only spined at the base, the shorter they are the longer a part ts
spined, and the shortest are spined in the whole length, o-12—0'47”", not divided into two groups; the
dermal spicules tornota 0:238—o-31"",; microsclera ancore spatulifere of two forms, large, with 5—6

teeth, 0'062—o0'071"", small, with 8—11 teeth, 0:032—0':038"™.

This interesting species grows as thin incrustations on Brachiopod-shells; its greatest extent is
1r™™ and the thickness is about o25™". The colour (in spirit) is whitish or light yellowish. The
surface is in the present condition of the sponge strongly hispid from projecting acanthostyli, but it

120 PORIFERA. III.

is probably not so in the fresh state. The dermal membrane seems to be quite wanting in the speci-
mens, so that I can say nothing about it or about pores and oscula.

The skeleton. The dermal skeleton; as the dermal membrane is quite or nearly quite wanting
I can say only little about the dermal skeleton; it seems to be of a construction like that found in
the preceding species and thus consists of bundles of spicules stretching from the main skeleton to
the dermal membrane. The main skeleton is quite of the common construction, the acanthostyli reach
to the surface and they project as said beyond it. A small amount of spongin is visible at the sub-
stratum around the heads of the acanthostyli.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli of a somewhat characteristic
shape; they have a head-swelling which is not large, but generally distinct, they taper evenly into
the apex, but the point is a little more abrupt. The largest styli have only spines below; the head
is beset with somewhat robust spines, and there are very small spines on the part just above the
head; the shorter the styli are the more spined they are and the smallest styli are spined near to the
point. The spines on the head are blunt, giving the head in the large styli a characteristic appear-
ance; the spines of the shaft are relatively largest in the small styli. The styli vary much in length,
but they are not divided into two distinct groups. The length is o12—o47™", and the diameter of
the head oor7—0037™". The smallest styli are the most numerous. 2. The dermal spicules are
slender and straight, or very slightly curved tornota, they are of the same thickness in the whole
length; the ends generally form typical tornotal points, only sometimes the shape is less pronounced.
The length is 0238—o'31™" and the diameter is oo0028—o004™. b. Aficrosclera; these are ancore
spatuliferee of two forms and sizes, large and small; they are both very beautiful spicules. 1. The
large ancore have a very slightly curved shaft and five to six elliptical teeth at each end; there
are somewhat narrow alz on the shaft, reaching a little longer towards the middle than the teeth.
Sometimes the number of teeth at each end is not equal, but may be five at one and six at the other
end; also some irregularity may be found, and when there are six teeth, generally one or two are a
little smaller than the others. The length is o1062—o071™, and the diameter of the shaft is o:004—
o'007™, 2. The small ancore have a shape somewhat similar to that of the large, but they have
eight to eleven teeth at each end; the number of teeth may also here be different at the two ends;
there are small ale on the shaft, but they are not directed to the sides but backwards, they are
thus not or almost not seen when the ancora is viewed from in front, and they are on the whole
difficult to see; from the fact that they are directed backwards they get a position similar to the falxes
of the teeth, and teeth seem in reality sometimes to be formed here, so that there is a circlet of teeth
all round; the construction recalling what is found in the ancoree of some of the Jofrochota species,
e. g. L. rotulancora (The Danish Ingolf Exp. VI, 2, Porifera, Part. II, r91, Pl. XVIII, fig. 6c—e). The
length is 0032—0038™", and the thickness of the shaft o003™. Of this ancora some developmental
stages were seen; they showed a dilatation with beginning teeth at each end, and they thus resemble
the developmental stages of the ancora in the mentioned /ofrochota species. The microsclera occur in
the tissue of the sponge, and to judge from a single place on one of the specimens they also occur
in the dermal membrane in somewhat great numbers; the small ancore are by far the most
numerous.

PORIFERA. III. I2I

This species is related to H. wmbeliifera Tops., but besides other characters this latter species
has only one form of ancore.

Locality: Station 89, the Denmark Strait, 64° 45’ Lat.N., 27° 20’ Long. W., depth 310 fathoms;
two specimens.

4. H. tenuisclera n. sp.
Pl. XI, Fig. 7.

Incrusting ; surface smooth. Spicula: megasclera,; the skeletal spicules acanthostyli with a small
but generally distinct head, somewhat densely spined in the whole length, 0:083—a19”", not divided
into two groups; the dermal spicules strongyla o:15—o:21"",; microsclera small tsancore unguifere with

5—8& teeth at each end, 0:016—o 020”.

This species forms incrustations on Bryozoa (Retepora and Cellepora), on Brachiopods and on
tubes of Placostegus tridentatus. Its greatest extent is about 15™, and it is very thin, not reaching
o5™". The colour (in spirit) is whitish. The sezface is smooth or it may be finely hispid from pro-
jecting acanthostyli, but this latter condition is certainly due to some damage. The dermal membrane
is a thin and transparent film. _Oscuda and fores were not observed.

The skeleton. The dermal skeleton consists of bundles of dermal spicules stretching from the

skeleton below to the dermal membrane, the spicules are somewhat penicillately spread outwards;
besides these bundles some more irregularly scattered spicules are seen; the bundles and spicules are
not at all densely placed, and the dermal skeleton is somewhat weakly developed. The main skeleton
is of typical construction, and it is rather regular, consisting of vertical acanthostyli. At the base
there is a very small amount of spongin, only observable with difficulty.
Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli; they are generally straight,
only rarely very slightly curved; the head is not large but as a rule distinct, and the shaft tapers
evenly from the head to the point. The styli are somewhat densely spined in their whole length,
sometimes the spines may be a little more dispersed towards the point; the spines are medium sized
and reclined, on the head they are somewhat long, blunt and radiating straight out. The styli vary
somewhat in length, but they are not divided into groups; the length is 0083—o'19™ and the diameter
of the head oor1—0'024™". 2. The dermal spicules are straight and slender strongyla; they are of
the same thickness in the whole length and sometimes they are a little polytylote; the ends may
be slightly swollen. The length is o15—o'21™ and the diameter o0028—o004™. b. Microsclera;
these are isancore anguifer; they are small and have a slender, curved shaft and five to eight
narrow teeth at each end; there may be some irregularity present, the teeth sometimes being of
different length and breadth and often the number of. the teeth is different at the two ends; there
are very narrow alz on the shaft, but they are difficult to observe. The curvature of the shaft is
generally very strong, but there is some variation on this point, especially in different individuals.
The length of the ancore, which is somewhat dependent on the curvature, is o016—o020™, and the
diameter of the shaft is about ooor™", The ancore are present in great numbers in the dermal
membrane but occur also otherwise in the tissue.

This species is very nearly related to H. biscutella Tops. but it is distinguished by several
The Ingolf-Expedition. VI. 3. 16

122 PORIFERA. III,

characters, the acanthostyli are smaller and the ancore in d¢scutella are described as having ten or
about ten teeth (“une dizaine”), and they are larger, 01027—0:030™"; finally the present species does
not show the “cellules sphéruleuses” mentioned by Topsent for dzscutella.

Locality: Station 6, 63° 43’ Lat. N., 14° 34' Long. W., depth 90 fathoms; station 32, 66° 35’ Lat. N,, -
56° 38’ Long. W., depth 318 fathoms; further it has been taken at 63° 18’ Lat. N., 21° 30' Long. W., depth
94 fathoms (The Fishery investigation steamer “Thor”); 61° 4o' Lat. N., 7°40’ Long. W., depth 135 fathoms
(Ditlevsen); 62° 23’ Lat. N., 2° 35’ Long. E., depth 217 fathoms (Ad. Jensen, the cruise of “M. Sars” 1902).
In all six specimens. The localities are situated in the Davis Strait, South and East of Iceland, West
of the Farde Islands and between the latter and Norway. :

Leptolabis Tops.

Incrusting forms ; external appearance, skeleton and megasclera as in Hymedesmia; the dermal
spicules tylota; the characteristic microsclera are forcipes of one or two forms, to these are added chele
arcuate and sigmata,

Topsent founded this genus in 1904 (Résultats des camp. scient. du Prince de Monaco,
Fasc. XXV. 181) and I think he was right, the presence of forcipes being here, as in the genus For-
cepia, of sufficient importance for the creating of a genus; moreover the dermal tylota seem to be
characteristic for the genus.

The genus Leftolabis comprises at present the following species:

1888. LZ. luctensis Tops. Arch, de Zool. exp. et gén. 2. VI, XXXVII, (Dendoryzx).
1892. L. exilis Tops. ibid. 2, X, XXII, (Lepéosia).
1904. L. forcipula Tops. Résultats des camp. scient. du Prince de Monaco, Fase. XXV, 182, Pl. XV, fig. 11.
« L. forcipula var. brunnea Tops. ibid. 182, Pl. XV, fig. 12.
« JL. arcuata Tops. ibid. 183, Pl. XV, fig. 18.
1905. L. zrritans Thiele, Zool. Jahrbiicher, 1905, 455, Taf. 31, Fig. 71 a—e (/ymedesmia).
L. asstmilis mihi.

I have remarked below, that I consider Z. forcipula var. brunnea as a definite and separate
species; the same may I think be said with certainty about Z. ductensis and exilis; on reading the description

of luciensis of 1904 I got the impression that besides exz/is perhaps still a third species may be
hidden here.

1. L. assimilis n. sp.
Pl. XI, Fig, 8.

Incrusting; surface smooth. The main skeleton weak. Spicula: megasclera; the skeletal spicules
acanthostyli divided into two groups, large and small; the large without head, somewhat densely spined
in almost the whole length, o42—o'53”"; the small with a slight head, spined in about the lower half,
o'089—oa21""; the dermal spicules tylota with small swellings, o-38—o'50””"; microsclera four forms;
chele arcuate o'014—0'038"", sigmata o'077—0'16"", spinulous forcipes of two forms, large, with legs

of equal length, 0:024—0'034"", small, with unequal legs, o-01g—o'018"™.

PORIFERA. III. 123

This species grows on a large stone together with a Sarcophyton and various sponges of the
genera Tedania, Hymedesmia and Crella. It forms an incrustation of a greatest extent of 30™, the
thickness being scarcely o5™™. The colour (in spirit) is greyish. The szface is smooth without pro-
jecting spicules. The dermal membrane is not especially thin and it is somewhat solid; it is charged
with microsclera, especially sigmata, and there are fibres of dermal spicules in it or just below it.
Oscula and pores were not observed.

The skeleton. The dermal skeleton consists of bundles and fibres stretching up to the dermal

_membrane, but in a very horizontal direction, and especially there are fibres running almost or quite
horizontally in or just below the membrane; the dermal skeleton is thus chiefly constructed of hori-
zontal fibres, and the fibres may reach some length; otherwise they have a more or less irregular
course, and they are often curved; they may be of different thickness but are often rather thick, e. g.
o'1ro™., The main skeleton consists of acanthostyli placed with the heads on the substratum and
directed vertically, or generally more or less obliquely upwards; they are much scattered and present
only in somewhat small number; the main skeleton is thus diffuse and irregular and on the whole
somewhat weakly developed. The acanthostyli are not evenly scattered over the surface of the sub-
stratum, but they are to some degree collected in bundles with a few spicules in each. There seems
to be a small amount of spongin at the base of the acanthostyli.

Spicula: a. Megasclera. 1. The skeletal spicules are acanthostyli which are divided into
two groups, large and small; the large styli are straight or a little curved; the basal end is rounded,
without any head-swelling or with this only very weakly developed, the other end tapers into a
middle-long apex. The styli are somewhat densely spined in almost their whole length, only a short
apical part being smooth; the spines are of medium size or small, and they are not reclined but
radiating straight out; on the basal part there may sometimes be some stronger spines. The length
of the large styli is o42—o0'53™™ and the diameter at the base oo17—o024™". The small styli are
straight; they have generally a somewhat distinct but small head, and the point is somewhat short;
the spinulation is continued somewhat beyond the middle so that the apical part is smooth. The
length is oo89—o'21™ and the diameter at the base oo10o—o014™. The small acanthostyli are of
rather scarce occurrence. 2. The dermal spicules are tylota; they are straight or sometimes slightly
curved, the shaft is cylindrical, not thickened in the middle; the ends have small but somewhat
distinct swellings; one end is a little thinner than the other and has the swelling more suddenly
marked, but this feature is only slightly pronounced and only noticed by close examination. The
length of the tylota is 038 - o50™™ and the diameter of the shaft ooo46—o007™. b. Microsclera are
of four forms, chele arcuata, sigmata and forcipes of two forms. 1. The chele have an evenly
curved shaft, the ale are lobe-shaped, somewhat narrow and deeply incised below, the tooth is
elliptical, of the same length as the ale. The chela varies much in size, the length is o014—0:038™
and the diameter of the shaft ooor—ooo04™™. The intermediate sizes are not numerous and hence the
chelz give the impression of being divided into two groups. 2. The sigmata are large, of common
shape and more or less contorted; they vary somewhat in size, the length is 0077—o'16™", and the
thickness is o1(0040—0'008™". 3. The large forceps is of the ordinary hair-pin-like shape with legs

of equal or about equal length; they have a round curve above, and the legs are somewhat divergent;
16*

124 PORIFERA. III.

sometimes the legs are curved slightly outwards and then a little more divergent below; these for-
cipes have thus a shape about as the large forcipes in Forcepia Topsentit (The Danish Ingolf Exp. VI,
2, 1905, Pl. XIX, fig. 4d). The forcipes are grittily or rugosely spinulous, and the legs are irregularly
rounded or somewhat pointed at the apex, without any knob; they are smooth on the inside of the
upper curve. The length of the forceps is 0024—0°034™", and the thickness of the rod is above in
the curve 0:0035—0'0056"". In single cases the forceps has the legs extraordinarily divergent, so that
the angle is obtuse; this feature is thus parallel to what is likewise the case with the forceps in
Forcepia Topsentii, (|. c. fig.4e). 4. The small forceps has the legs parallel or slightly divergent,
and one leg is longer than the other; this longer leg is curved slightly inwards; the legs terminate
with a little knob. This forceps recalls thus the forceps in Forcepia Thielei and F. groenlandica (The
Danish Ingolf Exp. VI, 2, Pl. XIX, fig. 5d, Pl. XX, fig. 34.); it is inconspicuously spinulous. This
forceps is very small, the total length from the curvature to the end of the long leg is oo14—o018™,
and the thickness above in the curve is about o0007™", Of the microsclera the chelze and sigmata
are numerous, they are seen especially in the dermal membrane, but occur also through the whole
sponge; the forcipes are not numerous but of somewhat rare occurrence, and they are not seen in the
dermal membrane; otherwise it must be remarked, that the small forceps is difficult to detect on
account of its very small size, and it is therefore very liable to be overlooked.

This species is evidently nearly related to Z. forcipula var. brunnea Tops. which I take to be
certainly a distinct species, not specifically identical with /orcipula; but the present species differs
from érunnea with regard to the size of both megasclera and microsclera; thus Topsent gives the
size of the chela to 0'033™", and he does not speak of variation in size; the large forceps in brunnea
has also a different shape, the legs being more divergent in their outer part; finally the acanthostyli
in assimilis have no specially strong spines at the base and have not the spines on the shaft reclined,
both these features being found. in drwnnea. I may also note, that in assimilis I have found no “cel-
lules sphéruleuses” which are mentioned by Topsent for drunnea. Topsent mentions, besides the
larger forcipes, some small ones of a length of oo13™" and very thin, but he does not describe them
more particularly; he thinks that they “représentent soit la form jeune soit une état athrophique de
cette sort de microscléres”. Developmental stages they cannot be, according to what we know about the
development of the spicules, the growth taking place only by apposition; there is on the other hand
also no reason to believe them to be atrophied forms. It is no doubt a special, small forceps, so that
brunnea, like arcuate and the present species, has also two forms of forcipes, large and small. —

Locality: Station 46, West of the Farée Islands, 61° 32’ Lat. N., 11°36’ Long. W., depth 730 fathoms.

One specimen.

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Fig.

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12.

13.

Plate I.

Tedania suctoria O. Schmidt. The large papilla is an oscular papilla. 1/;..............
Tedania suctoria O. Schmidt. A branched specimen, partly incrusting a Pétlota. */;.....
Tedania suctoria O. Schmidt. Incrusting specimen on an Allopora. "/y...... 0.0 eee eee
Tedania suctoria O. Schmidt. Pore-papilla in longitudinal Section, x about 30.........

Tedania suctorta O.Schmidt. Oscular papilla in longitudinal section, viewed from inwards,
x about 30. . 6 sca vidibis aie 0 d6 eis igeo RR aR ae orate naan TE EE a

Histoderma appendiculatum Cart. Most fistulee broken off, one ending in the way mentioned
im the text. 2/p 2.05 cin deren ieeMbeitpcnaias hese dim Gusto tr tie Sab cata osc a eens ae atigiaue agen a

Histoderma appendiculatum Cart. Small specimen. '/y....... 60. e cece eee ee eee ee eee es

Fitstoderma appendiculatum Cart. Section showing the small incurrent canals radiating
inwards from the space below the dermal layer, and some larger, excurrent canals. '/;

Flistoderma appendiculatum Cart. The inner body, removed from the dermal layer,
showing the openings of the incurrent canals, seen translucently as dark points. 2/;.

Histoderma appendiculatum Cart. A piece of the surface of the inner body at the base
of a fistula, showing the fibres at the surface, running together towards the base of
the fistula, a 325).405 0:6. 0..25. cod cnlvials as Lee eae a hea ee wy Cree Ries SRT ¢

Flistoderma appendiculatum Cart. End of a pore-fistula, = about 20...................
Histoderma physa O. Schmidt, groving on a stone; the specimen has two oscular tubes. */,

Histoderma physa O. Schinidt. Oscular tube with pore-sieve on the side, x about 3....

5 3

————s eer

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The Ingolf Expedition, VI.3. Lundbeck: Poritfera Ml, PL.

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Plate II.

Fiistodermella Ingolfi n. sp. The body somewhat contracted and broken below. */,.... —
Listodermella Ingolfi n. sp. Quite irregular specimen. 1/; ...........0 eee e cece cece ees _
Liistodermella Ingolfi u. sp. Somewhat tubular specimen. '/; ............ cece eee eeees _
fiistodermella Ingolfi n. sp. Small specimen. '1/y ....2.cc00+s5+000sss ease eeeuntebeneeee —

Fiistodermella coriacea n. sp. A typical specimen; above an osculum, most of the other
papillz are pore-papillze; below the sponge is broken; above there is a Verruca. */,. 16

Histodermella coriacea n. sp. Tubular, branched specimen, broken below; the pointed
papilla is an oscular papilla. 8/1. 5. css onc one bin + be nesie bo A —

Inflatella pellicula O. Schmidt. The base of attachment is seen; a tube is shown; rem-
nants of the inner body shine through the dermal layer; the specimen is damaged
MOVE 8/s 2.20... 0 snes dinars salvia’ grains ea 2 ween yale Mn aa ease fie eee at ar 18

Inflatella pellicula O. Schmidt. Two tubes present; the dermal layer somewhat contracted
and the peduncle broken; the-inner body is distinctly seen shining through. 2/;..... —

Inflatella pellicula O. Schmidt. The peduncle with stoles; a tube is seen; below the
remaining part of the inner body shines through. 2/:...........2..0seceeeecececeees —

Infiatella viridis Tops. Somewhat club-shaped specimen; four oscular and one pore-papillz
are seen; bottom material is seen adhering below; remnants of the inner body shine
through. 4/5 0... eee ue owen oa palniats bb. claw ole ware ose e BUnieee aaa ele 20

Inflatella viridis Tops. A somewhat low specimen; five tubes are seen, all contracted;
below some adhering bottom material */i3.06. ieetiw eee cio oe oe ee ek ee eis

Inflatella vividis Tops. Pore-tube, showing the pore-membrane and the skeleton of the
wall, >< GhOWE. 5. 60 soc ye ch oe Doane eye EEN HEIST SPER RVR SOO IN NG ae cn eta s es Phe ee —

Cornulum textile Cart. Somewhat damaged above. 1/;..............cceceeerceeeeneees 22
Cornulum textile Cart. with a Bryozoom. 4p... 6. ecco s esa cnsceheo cubes peeee uae _
Grayella pyrula Cart. A two-branched, compressed specimen; oscula are seen. 1/;...... 30

Grayella pyrula Cart. A two-branched specimen with two oscula. 1/;................-. —
Grayella pyrula Cart. Somewhat slender, club-shaped specimen with seven oscula. "/;.. —
Grayella pyrula Cart. An unstalked specimen; several oscula are seen. */;.......-...4- -
Grayella pyrula Cart. Small specimen with one osculum at the summit. 1/;......... ao

Grayella gelida n. sp. An osculum at the summit; the specimen shows wrinkles in the
curve, caused by ‘conttactton Wis casa sirs sans Rigen o's OWN AE GRD PE OO ae 34

ae i ees

Porifera WT, PILI.

Lundbeck :

The Ingolf Expedition, VI, 3.

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Plate Ul.

Hymedesmia rugosa n. sp. Two oscula are seems: 8/gs 6.5.6) ves a vs we wens Hae ny See Bp
Hymedesmia stylata n. sp. Two oscular papille are seen. '/;.......... 2. cece eee 57
Hymedesmia verrucosa n. sp. A fragment. “S/rniig cs cine visa se eee ees 58
Hymedesmia perforata n. sp. 8) ,.. os cxse cha Coe pe b ene bo tnu jo she ose Gs te oo ee 61
Eymedesinia basispinosa 1. Bpi 8g. kéisa Tee Wak oes nie Uslsibc ks os 84k 4 a.S os dea ee 64
HHymedesmia occulta Bow., with distinct papillae. '/y 0.0.0... cece cece cece e eee nes 67
Elymedesmia simillima un. sp. (@) on a stone together with a Hymeraphia (6); one oscular
and two pore-papillee are ster. .t/y... 5. i vpsimens crs spt vu sa swale ts skeen ees 69

Fymedesmia Bowerbanki n. sp. (a) and #7. clavigera nu. sp. (6) growing together on a stone;
below them is a Polymastia; c.is a Mesapos, and to the left of it grows a Bryozoon. '/;.. 62,75

Hymedesmia truncata n. sp. on a stone; six papillae are seen, 1/;........- eee eee e eee 77
Flymedesmia latrunculioides n. sp., in the middle the oscular papilla. 1/;...............5. 78

Hymedesmia crux O. Schmidt and H. mummulus n. sp.; the large sponge is H. crux,
oscula are distinctly seen; the circular, white spot is the base of a Hornera, on the
left side of it grows H. mummulus; a. is a Mesapos, 2p vc ccceccccccccnvvcnnceees 55, 83

Fymedesmia filifera O. Schmidt; peeled from its substratum. 14/; ...........-2eeeeeeeeee 86

Hymedesmia grandis n. sp. A large, somewhat folded specimen, seen from above; on two
places the substratum of large sponge-spicules is seen. */,........... SiC Re Ay pe ae 88

Hymedesmia grandis un. sp. A specimen cut through, showing the substratum of large
sponge-spicules; the bordering line of the sponge-tissue downwards is distinctly seen. '/; —

Hymedesmia: digstata-n. Sp. *]pova cs apne 00 RAGES Flas G Oe evo bo Tk Tae Sls ey a go
Hymedesmia trichoma n. sp., growing on an Astarte-shell. '/p..... 0.00. c cece eee eee eee gI
Hymedesmia dermata n. sp. Osctilar cones are seen. 4/,.. 6.5 .505.0.0000ce ss Won eae 107
Hymedesmia tornotata u. sp, ona Brachiopod. */;..........s.se0'ss ss eae + os eee ea 109
Hymedesmia mucronella n. sp. on a fragment of a S7pho. 1) 0... cece ee eee eee IIo

Grayella carnosa Tops. Cushion-shaped specimen, growing on a piece of Biemma rosea. */;. 36

Grayella carnosa Tops. Erect specimen with two oscula at the summit; at the base some -
adhering bottom material... */, ....< 5 ssijwehouee eens <> 5 een Oe eens es ee hey 90

j
.

The Ingolf- Expedition, V1.3. : Lundbeck: Porifera i, PIII

19 18

20 21

wee stead:

=

*

Fig. I.

Plate IV.

: : Page
Tedania suctoria O. Schmidt, @ styli of various sizes, 4 tylota x 200, c rhaphides of the
three different sizes, all from one specimen x 380, @ the upper end of one of the
largest and one of the smallest rhaphides ><. 1400...) 2.0... doin. sg pee eens mes I

Histoderma appendiculatum Cart. a tylota with intermediates to strongyla from the dermal
layer and the inner body x 165, 4 chele arcuate, side and front view >< 1000,
¢ Sigmata < 460... 60555. 1h pe soe ee Pi lee Sasiie tele salah Gk yw ee aoe a 7
Histoderma physa O. Schmidt, @ strongyla of various sizes = 165, 6 chele arcuate, front
and side view x 1000, ¢ trichodragma >< 380.03 .i..U.2h. . Weees ene seen eee ee

Histodermella Ingolfi n. sp. a tylota of various sizes, 6 a young and an older develop-
mental stage, c acanthoxea, @d a not quite young developmental stage x 200, ¢ chele
arcuate side view, a little from behind, and front view = 1000, f sigmata <x 460.... 14

Flistodermella coriacea n. sp. @ strongyla of various sizes from the dermal layer and the
inner body; with the magnification used the spinulation of the ends is not seen, 4 acantho-
strongyla >< 165, c ends of two strongyla, showing the minute spinulation < 700... 16

Inflatella pellicula O. Schmidt, @ strongyla of various sizes, 6 a developmental stage x 200 18
Inflatella viridis Tops. a strongyla of various sizes, 6 a developmental stage x 165...... 20

Werner u. Winter, Frankfurt®M.

Lundbeck: Porifera I, PLIV.

ge.

Uf Expedition, VL3.

Plate V.

: Page
Fig. 1. Cornulum textile Cart. a strongyla x 200 ¢ the two ends of a distinctly spined strongylum
>< 700, ¢ chelez arcuate, front and side view x. 1400, d toxa = 340..............05. 22

— 2. Grayella pyrula Cart. a@ tornota, 6 acanthostyli x 255, ¢ chele arcuate, front and side

VIEW >< TOO0.. vie oe ine Sp bs ae w Ming a hs era o 0 atm a ls 9 Fie, 50. Gn 30

— 3. Grayella gelida nu. sp. a@ tornota, 6 acanthostrongyla = 255, ¢ chele arcuate front and
side view >< 1000 ....0...6..) Ps gos ae.) eee ey mr es en 34

— 4. Grayella carnosa Tops. a tornota, 6 acanthoxea, c a developmental stage >< 255........ 36

— 5. Hymedesmia Koehleri Tops. a acanthostyli of various sizes, 4 polytylote strongyla x 255)
c chele arcuate, front and side view >< 1000. The spicules are from a typical specimen 42

— 6. Hymedesmia lacera u. sp. @ acanthostyli of various sizes, 4 strongylum >< 255, ¢ chela
arcuata, SIGE VIEW ><) TOOL 6600s .c sain vu aie gression ol olbce, BRD Wome eenee I ore cate aes iin eae 44

— 7. Hymedesmia storea un. sp. @ acanthostyli of various sizes, 6 strongylum > 255, ¢ chela
ATCURMB, SIGE VIEW >< TOO. 6666 556 oie canis) oe opie: wan ele a bin dig sain ene te ae 45

— 8 Hymedesmia lamina n. sp. a@ acanthostyli of various sizes, 4 strongylum x 255, ¢ chelz
arcuatee, side and. back view. >< 10QQe.i./50<0Fgccck enews EMeT VemouN aay 5 eh0 0S Gen 46

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Plate VI.

Page
Fig. 1. Hymedesmia mollis n. sp. a@ acanthostyli of various sizes, 4 strongylum x 255, c chelez

arcnates, side VieW ><) LODO 5 0.s./i0ic ope vintce See pie ors 9s ne 4 ae ead oe ee 47

— 2. Hymedesmia curvichela un. sp. a acanthostyli of various sizes, 6 strongylum > 165, ¢ chela
arcuata, side view >< 1I000.......... BS a tie dipia viens Ka 4.9 0h Gaihe’g COS RL La ee 48

— 3. Hymedesmia rugosa n. sp. a@ acanthostyli, large and small, 4 strongylum x 255, ¢ chele
arctiatee, front and side view >< JOO. 66 ss «ssienass9uc0 secs ee ck sane oes EA ene 50

— 4. Hymedesmia splenium n. sp. a@ acanthostyli, large and small, 4 strongylum x 255, c chela
arcuata, side view x I000........+... Rs | See rer, Per ee ye me eee. 51

— 5. Hymedesmia tenuicula n. sp. a@ acanthostyli, large and small, 4 strongyla x 255, ¢ chela
arcuata, side VIEW %< TO00. 2... seve ies coved cdnes oy uweyhwn's Seman oe bee ee aeeennae eee 52

— 6. Hymedesmia similis un. sp. a acanthostyli, large and small, 4 strongylum >< 255, ¢ chela
arctiata, side VIEW >< QQ 2.5.6. eeesins sine s op woiec nih ik s/eleln wile selenite amie enna 53

— 7. Hymedesmia nummulus n. sp. a@ acanthostyli, large and small, 4 strongylum x 165,
¢ chela arcuata, side: view >< 1000... ..0.):/sie.s's «ers nanan eee alse eee 55

— 8 Hymedesmia dubia n. sp. a acanthostyli, large and small, 4 strongylum x 255, ¢ chela
arcuata, side view, a little from the front so that the flat front side of the shaft is

— 9. Hymedesmia stylata n. sp. a@ acanthostyli, large and small, 4 strongylum >< 255, ¢ chela
arcuata, side view, a little from the front > 1000; when seen accurately in side view,
the ale would be more claw-shaped ... 6. icectn oss on eect a s inne en eae 57

Foritera Im, Pl. V1.
Werner 2 Winder Frankfurt.

Landheck

na

aaeecere Sachin

© BV sist ©

Plate VIL

: Page
Fig. 1. Hymedesmia verrucosa n. sp. @ acanthostyli of various sizes, 4 strongylum x 255, ¢ chelz

arcuate, oblique front view and side view >< I000........... sss see e teen tence eee ees 58

— 2. Hymedesmia procumbens un. sp. @ acanthostyli of various sizes, 6 tornotum >< 255, ¢ chela
arcuate, Side. View >< 1000 0.5.6... sc hs sadeean es is 9.6 «5-0 Sw bee hie Bue eh ae Rk ee 60

— 3. Hymedesmia perforata n. sp. a@ acanthostyli of various sizes, 4 tornotum > 255, ¢ chele
arcuate: of various sizes, sife view ><. 1000... 2: shes isdsy beneranele ens see geen 61

— 4. Hymedesmia clavigera nu. sp. a acanthostyli, large and small, 4 tornotum x 255, ¢ chela
arcuata, side view >< 1000... apis ab sical ss, SERED © ou wince «Pets piano aaa een 62

— 5. Hymedesmia platychela nu. sp. a acanthostyli of various sizes, 4 tornotum > 255, ¢ chela
arcuata, front view >< 1000; One tooth 1s cleft./.-).. <s5:giss sleuee cle cents ernie een 63

— 6. Hymedesmia basispinosa n. sp. a acanthostyli, large and small, 4 tornotum x 255, ¢ chela
arcuata, side VIEW >< T0006. iiicke samen eee baie abe neg re alerts ail eie eee eenn ee 64

— 7. Hymedesmia longistylus nu. sp. a acanthostyli of various sizes, 4 tornotum >< 165, ¢ chela
arcuiata, side VIEW: >< LOO. 65.6% 6.6 6 Wills sole wins a awid nid eben ane Gea felas pie len tetera am ee 66

— 8 Hymedesmia occulta Bow. a acanthostyli, large and small, 4 one of the tornota, ¢ one of
the oxea from the dermal skeleton, d one of the thicker oxea from the dermal mem-
brane, ¢ one of the specially thick dermal oxea from the specimen mentioned in the
text >< 165, / chele arcuate, side and front view > I000............c cece eee ee eens 67

— 9. Hymedesmia simillima un. sp. a acanthostyli, large and small, 4 dermal oxeum, ¢ one of the
thick dermal oxea >< 165, @ chela arcuata, side view >< I000......... eee e ee eens 69

:
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Werner u. Winder, Fonkhren.

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Plate VIII.

: Page
Fig. 1. Aymedesmia baculifera Tops. a@ acanthostyli of various sizes (from a specimen with large
styli), 6 tylotum x 255, ¢ chela arcuata, side view > I000..........-++..ee+sseseeee 71
— 2 Hymedesaia, levis nu. sp. ba acanthostyli Of. various sizes, 4 polytylote tylotum >< 255,
- i 73
=e, 3 pes
dee > 74
“ 74
ager % Hymedesnia Se aie n. sp.
75
— 6.
— 7. Hymedesmia latrunculioides n. sp. a acanthostyli, 4 tylotum > 340, c chela arcuata, side
view, a little from in. front ><. L000 « 00sisieo:5.0.0'9:0:0'm «4m/sisinndwia glee 5 mortals oe ae ae ee 78
— 8 Hymedesmia trregularis n. sp. a acanthostyli of various sizes, 4 polytylote dermal stylus
>< 255, ¢ chele arcuate, front and side view >< 1000... 0553; touscwenenespeeaweass 80
— 9. Hymedesmia proxima nu. sp. a@ acanthostyli, large and small, 4 dermal stylus x 255,
¢ chele ‘arcuate, front atid:side view? 5220004. Sri dirs cs ae Po ie ie hi ines ae _ Sx
— 10. Hymedesmia crux O. Schmidt, @ acanthostyli of various sizes, 4 subtornotum x 255,

c chele arcuate, front view (the spines on the back of the shaft are seen shining
through) and side view, @ seen from the end >< 1000..........cc sce eee cece ee eeeeees 83

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Plate IX.

° Page
Fig. 1. Aymedesmia aenigma un. sp. @ acanthostyli of various sizes, 4 tornotum x 255, c—/ asteroid
chelze in various views, c the axis distinct, with the convex side to the right, d the
axis cannot be pointed out, ¢ front view, the axis in the middle, / seen from the end,
g a developmental stage = I000............... sin, oi ie sca, ra ecg: kon. pg oe aR ee ge 84

— 2. Hymedesmia filifera O. Schmidt, a acanthostyli of various sizes, 4 strongylum > 255, ¢ chela
arctiata, SIGE VIEW df TOKO. 6a sn soe occa sage ns eae aces & hole ley pba wie do wth ae 86

— 3. Hymedesmia grandis n. sp. a@ acanthostyli, large and small, 4 strongylum >< 255, ¢ chele
arcuate, front and side view >< 1000, @ sigmata of various sizes x 460............. 88

— 4. Aymedesmia digitata un. sp. a acanthostyli, large and small, 4 tylotum >< 255, ¢ chela
arcuata, side view >< 1000, ¢ sigmata ‘>< 460...:55. 00 s00 0s ces viewe ow cial weer ees go

— 5. Hymedesmia trichoma nu. sp. a acanthostyli, large and small, 4 tylotum > 255, ¢ chela
arcusta, side view >< 1000, @ sigmaiie.2¢ 4602.00. shee ev avs 6s stuavuee ree amen cued gI

— 6. Hymedesmia macrosigma nun. sp. @ acanthostyli of various sizes, 4 strongylum x 255,
c chelz arcuate of various sizes, side view < 1000, d sigmata, large and small > 340 92

— 7. Hymedesmia pugio nu. sp. a@ acanthostyli, large and small, 6 dermal stylus = 255, ¢ chela
arcuata, side view >< 1000, @ sigmata >< GBS (00. sisa seukaau tees cuenay Ceeeae 94

— 8. Aymedesmia consanguinea un. sp. a acanthostyli, large and small, 4 tornotum x 255, c chela
arcuata, side view 5 1000, @ MigmBta Se SEC. ia vinta cess stuck ta sass bc a ereen 95

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Plate X.

Fig. 1. Hymedesmia planca n. sp. @ acanthostyli, large and small, 4 tylotornotum > 255, ¢ chelz
arcuatee of various sizes, front and side view x 1000, @ large sigmata, ¢ small, circularly
Curved! Sigmiata 5< S85... s.o.0ic 5 5s:0:8 + Voce evra rie dene deeial aint oce.s8 oN arene ORI pe latte nan ra

— 2. Hymedesmtia cultrisigma nu. sp. a acanthostyli, large and small, 4 tylotum > 255, ¢ chela
arcuata, side view = 1000, @ sigmata of the large, peculiar form, e sigmata of the
ordinary -form 5<) 585.0205 fe. ss oo elanieies waters ciel ase ecole i Sakecgts MecabUtih tae rie arta tia ae reac

— 3. Hymedesmia mucronata Tops. a acanthostyli of various sizes, 6 oxytornota >< 255, ¢ chela
arcuata, side view, d—e the peculiar chela, @ side view, ¢ seen in oblique front view
and somewhat from the end, in this view the points of the processes are not seen
and the processes appear therefore rounded at the ends x 1000, / sigmata x 585...

— 4. Hymedesmia tenutsigma un. sp. a acanthostyli, large and small, 4 polytylote strongylum
>< 255, ¢ sigpmat 3< 460 oe hae ocd a 0.0/9.5 se qa) 6 Galpin ASA els whee ie eS ak aan

— 5. Hymedesmia Diyjardinit Bow. a acanthostyli of various sizes, the middle one with a slight
head-swelling on account of the shaft being thick below, 4 strongylum and tylotum

— 6. Hymedesmia primitiva n. sp. a acanthostyli of various sizes, 4 polytylote strongylum >< 255

— 7. Hymedesmia longurius n. sp. a@ acanthostyli of various sizes,. 6 a thinner and a thicker
atrongylim: 5< 256 «26 6-6. see cS cs baa eh Oe AeA a EMS Sek ses Sh pon eoeee coe enae

— 8. Aymedesmia equata nu. sp. a acanthostyli of various sizes, 4 strongylum < 255, Solem anaes

Page

97

100

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Fig. 1.

Plate XI. _

Hymedesmia dermata n. sp. a acanthostyli, large and small, 4 strongylum > 255........
Hymedesmia tornotata n. sp. a@ acanthostyli of various sizes, 4 tornota with microspined

COME SE-DES Sis sect «5 Sei ois # bn ein 9/9 3 ¥ie «pie arSip wiecale 8 in is peso aka nn ane alae 209‘

Hymedesmia mucronella n. sp. a@ acanthostyli, large and small, 6 tornotum, the upper end
With A. WUCTO: 56.266 0... os sais ew coves tae deren amas os 4 Aaa ad ergata i eeaee IIo

Flymenancora interjecta n. sp. a@ acanthostyli, large and small, 4 tylotum >< 255, ¢ ancoree,
front and side view > 1000, @ sigmata 5<¢ -460....5 05.255 Weta s oot urea sey eee 117

Hymenancora conjungens n. sp. a@ acanthostyli, large and small, 4 tylotum with somewhat
swollen ends >< 255, ¢ ancoree, side view and oblique front view, >< 1000, @ sigmata

Hymenancora duplicata n. sp. a acanthostyli of various sizes, 6 tornotum x 255, ¢ ancoree
spatuliferce of the large form, oblique front view and side view, @ ancore spatuliferze
of the small form, front view and side view, the latter shows two smaller teeth at the upper
ON FS TOOD. ieee cei s sew aiset see wie 5 8s dlp ale nib oopie,s Mie male 6a tne eit ae 119

Hymenancora tenuisclera n. sp. a acanthostyli of various sizes, 4 strongylum >< 255,
¢ ancore unguiferee, side view, with more and less curved shaft = 1000............ 121

Leptolabis assimilis n. sp. a acanthostyli, large and small, 4 tylotum x 255, c chele
arcuatee of various sizes, side view > 1000, d@ large forcipes >< 1000, ¢ small forcipes
=< 1400, J sigmatin “9<" 4400 a5.) ssid vais fo Rap es SA ger teh PRET ee 122

PLNL

‘fera Il,

Po

Fandheck

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TON.

inter Frankhy

Werner wW

INGOLF-EXPEDITIONEN

1895—1896.

STATIONERNES PLADS, DYBDE 0G BUNDTEMPERATUR.

; Station _Dybde Bund- | See _Dybde Bund- | pe at Dybde | Bund-
/ N. Brd. | V. Lgd: |idanske| tempe- N. Brd. | V. Lgd. |idanske| tempe- | N. Brd. | V. Lgd. |idanske| tempe-
ae Fvn. ratur NE. Fvn. ratur Nr, Fyn. ratur
|
I 62° 30° Ba 132 Mh 24 63°06 | 56°00’ 1199 2°4 45 oo bee yf 9° 43° 643 4°17
2 63° 04° 9° 22' 262 5°3 25 63° 30° | 54° 25° 582 RK Be 46 61° 32° 11° 36 720 2°40
3 63° 35° 10° 24’ 272 0°5 : 63° 51 | 53°03 136 47 6x2'32" 13° 40 950 3°23,
4 64°-07 1S egy a 237 acs 26 63° 57° 52° 41 34 0°6 48 61° 32’ ha 1150 3°17
5 64° 40° | 12°09 155 64° 37° |. 54° 24° 10g 49 62° 07’ 15°07’ 1120 2°91
6 63° 43° | 14°34 go 7°0 27 64° 54 | 55° 10° 393 3°8 50 62° 43° | 15°07’ | 020 $eX3
7 (hain & ES CAT. 600 4°5 28 65° 14° | 55° 42’ 420 3°5 51 64° 15 14° 22’ 68 7°32
8 63° 56 | 24° 40° 136 6°0 29 CY ae? Ma MY” le 9 a 68 0°2 52 63° 57 13° 39° 420 7°87
9 64° 18° 27° 00’ 295 5°8 30 66° 50° | 54° 28° 22 1°05 53 63° 15° se 07’ 795 3°08
10 64° 24’ | 28° 50° 788 305 31 66° 35° | 55° 54° 88 E26) 54 63° 08’ | 15° 40 691 3°9
IL 64° 34° | 31° 12’ 1300 1°6 32 66° 35° | ~56° 38 318 9 55 63° 33 | 15°02’ 316 5°9
12 64° 38° | 32°37’ 1040 0°3 33 672 §7' 55°30. 35 0°8 56 64° oo 15° 09! 68 7°57
13 64° 47° | 34°33 622 3°0 34 G5O 17 2| 5417" 55 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’ 211 0°8
15 66° 18’ | 25° 59 330 | —0°75 36 61° 50° | 56° 21’ 1435 1°5 59 65° 00° | 11° 16’ 310 | —O°r
16 65° 43° | 26° 58" 250 6°r 37 60° 17” | 54°05 1715 1°4 60 65°09. |: ae a7" 124 0°9
17 62° 49° | 26°55 745 3°4 38 59° 12 | 51°05’ | 1870 173 61 65° 03° | 13° 06 55 0°4
18 61° 44’ | 30° 29 1135 3°0 39 62°.00' | 22° 38’ 865 2°9 62 | 63°18 | 19° 12 72 7°92
19 60° 29’ | 34° 14 1566 2°4 4o 62° 00’ | 21° 36 845 3°3 63 | 62° 4o’ | 19° 05 800 4°0
20 58° 20° | 40° 48’ 1695 1°5 41 61° 39 | 17° 10° 1245 2°0 64 62° 06’ | 19° 00° 1041 By
21 58° or | 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° 11’ 645 0°05 66 61°33" {| -aar- as 1128 3°3
23 60° 43° | 56° 00° Pasion: : 44 61° 42’ 9° 36 545 4°8 67 61° 30° | 22°30’ 975 3°0

hail . : ng >
1899. Vol. I, Part I. 1. Report of the Voyage by C.F. Wandel (1 plate) .....
; Ss Kr. 25,00 (Sh. 30)
2. Hydrography by Martin Knudsen (34 plates)........
1goo. — Part II. 3. The deposits of the sea-bottom by AaB. Boeggild i

1899. Vol. IL, F Pert I. The ichthyological results by Chr. Liitken (4 plates) ..

1899., Vol. III, Part I. Pycnogonide by 7%. Meinert (5 plates) Srecltas cab gee Siete:

1908.

1903. Vol. IV, Part I, Echinoidea, Part I, by 7h. Mortensen (ax plates). 7...

1907.

1904. Vol. V, Part I. Pennatulida by Hector FE. Jungersen (3: plates)... 2...
1902. Vol. VI, Part I. Porifera (Part 1), Homorrhaphide and Heterorrhaphide

HITHERTO PUBLISHED:

uenartslno mores Siege io han toned weak eieaphe 8,00 ( - 11) ae
4. Current-bottles by C.F Wandel (I plate). isu Lome ee: ea

— Part Il. On the Appendices genitales. (Claspers) i in the Greenland-

Shark, Somniosus microcephalus (Bl. Schn.), and other Sela-

chians by Hector F. E. Jungersen (6 plates)..... a9 on tn i ok
— . Part Ill. Nudibranchiate Gasteropoda by R. Bergh (5 plates)...
— Part IV. The North-European and Greenland Lycodinz by
Adolf Severin Jensen (to plates)... .. Aa sves ete So 7ocat

_ Part II. Crustacea Malacostraca, I: Decapoda, Euphausiacea,
Mysidacea by H. J. Hansen (5 plates) parent peers benches SM gars

— Part Il. Echinoidea, Part II, by Th. Mortensen (19 plates) eke

by Wil, Lundbeck IiGepranee) cease, ke. os a
— , PartIl. Porifera (Part 2), Desmacidonidze Sa by Will. Lundbeck
OSA RTRR) hee iN ee ee APRS Ed eS «| 1 ns a hat Cee a
— Part II. Porifera (Part 3), Tesumisdonide (Pars) by Will. Lundbeck —
(LE PIAteS) 2 AG rare. ae i 2s, Le a eee ee ried

= Sake

a

ae eer
ae ey

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ations

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