James Scott Bowerbank.

A monograph of the British Spongiadæ online

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KSW FORMS OF SPICULA FOUND SINCE THE PRECEDING ONES
WERE DESCRIBED AND FIGURED.

226. BispiNULATE. X 175 linear. — ^Fxom JSalimemia

patera, Bowerbaidc. Page 15.
229. Trisfinulatb. X 175 linear. — From Halicnemia

?patera, Bowerbamk. Page 15.
830. The normal form of spinulate spiculum irom the same

sponge as the spicdia represented by ilgs. 228 and

229. X 175 linear. Page 15.

('231. Undeveloped forms of spinulate, bispinulate, and
382. trispinulate, from the same sponge as the three pre-
233. ceding £gures. X 175 linear. Pi^e 15.

234. 'SfiCULATBD INEQUI-ANlBUIiATI» TRIRADIATE, with

cyKndricai entiwly spined radii. X 808 linear. —
From DictyooyUndms Fiekersii, Bowerbank, MS.



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268 ANATOMY AND PHYSIOLOGY

Pio.

From the West Indies ? This spiculum is an ex-
ternal defensive one. The triradiate rays are im-
bedded immediately beneath the dermal membrane,
and the spicular ray is projected through it at right
angles to its plane ; they are very numerous,

235. Spiculated attenuato-equiangular triradiate:

VERTiciLLATELY spiNED. X 660 linear. — ^From an
undescribed sponge. Freemantle, Western Aus-
tralia, I have not seen the spiQcimen whence this
spiculum is derived, but^ reasoning from our
knowledge of the form and situation of the spicu-
lum represented by Fig. 234, there can be little
doubt of its being an external defensive one.

236. Spiculated cylindro-equiangular verticillately

SPINED. X 660 linear. Freemantle, Western
Australia. From the same slide of Sponge spicuia
in which the form represented by 235 was found.
There can be little doubt of its being an external
defensive organ.

237. Inequi-furcato-triradiate. X 183 linear. — These

spicula are from a new species of calcareous
sponge, probably a Grantia. They were sent to
me mounted in Canada balsam by my friend Mr.
George Clifton, of Freemantle, Australia. They
occur loosely fasciculated, and their mode of dis-
position is probably on the surface of the sponge.
They differ considerably from each other in length
and in the width apart of the prongs of the fork,
but they all have them unequal in length. It is
probably an auxiliary skeleton and external defen-
sive spiculum.
238 and 239^ Attenuato-cylindrical verticillately
SPINED. X 183 linear. — ^From Hymeraphia ver-
tidUata, Bowerbank. These spicula are dispersed
in abundance on the interstitial and dermal mem-
branes of the sponge. In the young state the
spicular are long, slender, and perfectly smooth ;



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OF THE 8P0NGIADJS. 269



Fig.



in the course of their further development they
assume a monilliform appeal^nce, as represented
by Fig. 239, and in their adult state are verticil-
lately spined, as represented by Fig. 238.

240. Inplato-acerate, with incissurate terminations.

X 660 linear* — ^From Hymeraphia veriicillatay
Bowerbank. A terminal portion only of this spi-
culum is represented by the figure, the incissurate
character being the only novelty in the form. The
incissuration varies in degree to a considerable ex-
tent in different spicula, in some cases being very
slightly produced, in others rather beyond that re-
presented by the figure. The rudiments of a third
ray are sometimes apparent. This form is an aux-
iliary skeleton spiculum. They are found thickly
clustered round the primary spicula of the skeleton.
They differ essentially from porrecto-temate spicula
in having both ends cleft or radiate, which is never
tlie case in any of the ordinary temate forms.

SPICULA, THE POSITIONS OP WHICH AEE UNKNOWN.

241. BlEECtJEVO-QUATEitNATE, MEDIALLY SPINED. Sponge

unknown, X 660 Hnear. — Probably an internal
defensive spiculum.

242. Spintjlato-ensifoem, from a parasitical sponge from

Western Australia. X 130 linear. — I obtained
this singular form from a parasitical sponge from
Western Australia. This curious sponge, in the
formation of its skeleton, appears to have appro-
priated the spicula of every other kind of sponge
that came within its reach.

243. AcuATE: BASALLY ebctangulatbd. X 150 linear.

— 1 obtained this spiculum from the spongeous
matter scraped from the base of Oculina roaea^
by a dealer in the process of cleaning the coral.
It is not a malformation, as there are several



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270 ANATOMY AND PHYSIOIiOGT

Fig.

of them in the same slide, and they are all angu-
lated to the same extent. It is probably an inter-
nal defensive spiculum.
244, 245, 246. Tubkrculatbd fusifobmi - cltindri-
CAL. — ^The beautiful spiculum represented by Fig.

244, X 660 linear, is siliceous. It has been re-
peatedly found in the matter obtained by washing
the roots of Oculina rosea and other corals from
the South Sea, by my friends Messrs. Matthew-
Marshall, Legg and IngaU, but the sponge, whence
it is most probably derived, has never yet been
determined. It is remarkable as being the only
well-defined and perfect siliceous spiculum that
has yet been observed to possess the short stout
tubercles that are so characteristic of its structure.
Fragments of two other spicula, possessing similar
characters, have been observed by me, and are re-
presented by Figs. 245 and 246. In the specimen
represented by Fig. 246, X 260 linear, the tuber-
cles are less in number, but are considerably more
produced, and their terminations are more abruptly
truncated. In the spiculum represented by Fig.

245, X 260 linear, they are stiU more widely, dis-
tributed, are shorter and more inclined to be coni-
cal, so that there is little doubt that they have be-
longed to three distinct species of sponge. But in
all three of them there is one peculiarity, that of
the manner of the disposition of the tubercles on the
shafts of the spicula, where we observe them to be
disposed in more or less regular longitudinal lines,
and that the tubercles forming each line alternate
with those of the line next to them, so that they
assume the appearance of a spiral arrangement.
The close alliance in the structure of these spicula
would seem to indicate the existence of a peculiar
tribe of sponges, with which we are at present en-
tirely ttnaoquainted.



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or THE SPOMOIADJI. 271



ANATOMICAL 8TEUCTUBJB 01 SPICULA.

247. Distal termination of a porrecto-ternate Bpiculum from

Tethea cranium, with angular distortions from ex-
ternal pressure. X 260 linear. Page 6.

248. A portion of an adult spiculum from Sponffilla

fluviatiliSy charred to exhibit the thin membrane
of the central cavity of the spiculum. X 260
linear. Page 6.

349. A portion of an immature dpiculum from S^onffiUa
lacustria, charred to exhibit the dense membrane
lining the large central cavity in the young spicu-
lum. X 260 linear.

250. A section at right an^^es to the axis of the upper

part of the shaft of a ternate spiculum from Geodia
Barretti^ Bowerbank, MS., exhibiting the concen-
tric layers. X 260 linear. Page 6.

251, 852. Portions of charred spicula from the skeleton

faficiculi of Tethea cranium^ exhibiting their hol-
low condition after incineration. X 90 linear.
Pages.

253. A portion of a spiculum bom Buplecteila asperffilium,

Owen, slightly charred, exhibiting the concentric
layers of silex. X 90 linear. Page 11.

254. A portion of an adult spiculum from the skeleton of

Geodia McAndremi, Bowerbank, MS., cracked by
the application of cold water while in a heated
state. X 90 lineal". Page 9.

MEMBRANOUS TISSUES.

S'55. !l?lBEO-MEMBRAKotJS HBstJE. Containing a singlc layer
of parallel fibres on a portion of the membrane
from an excurrent caned of one of the oommon
hoaeycomb sponges of commerce. X 660 linear.
Pages 67, 99, and 100.



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272 ANATOMY AND PHYSIOLOGY

Fig.

266. FiBBO-MEMBBANous TISSUE. TVom the dermal mem-
brane of a Stematamenia. X 183 linear. Pages
100, 211.

257. FiBBO-MEMBBANOus TISSUE. lu wMch the layers of
fibre cross each otter at about right angles. From
AkyonceUum robusta, Bowerbank. X 660 linear*
Page 100.

259. iPiBBO-MEMBBANOUs tissuE. In which the layers of
fibre cross each other at various acute angles.
From AlisjfonceUum rdbusta, Bowerbank^ X 308
linear. Page 100.



FIBROUS STRUdTURES.

PBIMITITE FIBBOUS TISSUE.

269. Pbimitive eibbous stbuctubes. Dispersed (m the
inner surface of a portion of the dermal membrane
of a young Stematumema; a a, cells in situ^
which have each produced a fibre. X 660 Unear.
Page 70.

260. Detached specimens op pbImitivb pibbous tissue.

In progressive stages of development. X 660
linear. Page 70.

KEBATOSE PIBBOUS TISSUE.

261. Solid kebatose pibbe. From a cup-shaped specimen

of the best Turkey sponge of commerce, in the
condition in which it came from the sea. X 175
linear. Page 73.

262. Spiculated kebatose pibbe. From Chalina oculata,

Bowerbank. X 176 linear. Pages 74, 208.



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9F THE SPONGIADjE. 273

263. SpicujiATED KKEATOSE FIBRE. From Chalina Mon-

tagui^ Bowerbank, a young fibre in course of
development (a) the apical spiculum. X 175
linear. Pages 74 and 108.

264. MuLTispicuLATED KERATOsE FIBRE. From Bes-

macidon a^offropila, Bowerbank. X 108 linear.
Page 75.

265. Ineqtji-spiculated keratosb fibre. From Ba-

phyrua Griffithm, Bowerbank. X 175 linear. Pages
75 and 201.

266. Simple fistulose keratosb fibre. From Spongia

Jistularia, Lamarck. X 108 linear. Pages 76 and
209.

267. Compound fistulose keratosk fibre. From the

skeleton-fibres of Auliskiay Bowerbank, exhibiting
the secondary canals radiating from the primary
ones. X 300 lineaf. Pages 77 and 210.

268. Compound fistulose keratose fibres. From

4uliskia, Bpyverbank^ exhibjitiiig the general cha-
racter of the fibr«. X 100 lineaa*. Pages 77 and
210.

269. Regular arenated keratose fibre. From one of

the Bahama sponges of commerce. X 175 linear.
Page 77.

270. Irregular arenated keratose fibre. From Z)y-

sidea/ra^ilisy Johnston, having the siliceous grains
very abundantly packed in its substance. X 108
linear. Pages 78 and 211.

271. Irregular arenated keratose fibre. From Dy-

sidea fraffilis, Johnston, exhibiting its general cha-
racter in situ. X 108 linear. Pages 78 and 211.

272. Irregular arenated keratose fibre, showing how

the young fibre picks up the ^rain of sand and
surroujids it with keratode. X 108 linear. Pages
63, 78, and 211.
27 3, Hetro-spiculated keratose fibre. From Dip-
lodemiavesiculafBoweThmk. X 175 linear.
74 and 202. (See Plate XIV.)

18



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274 ANATOMY AND PHYSIOLOGY

Fig.

274. Smooth solid siliceous fib&e. From McAn-

drewsiuy Gray. X 175 linear. Pages 13, 79,
and 204.

275. TuBERCULATED SOLID SILICEOUS FIBRE. YtomDactylo-

calyx pumiceay^\Mi(^h\}iY. X 108 linear. Pages
79 and 204.

276. TuBBRCULATED SOLID SILICEOUS FIBRE, veiy promi-

nently tuberculated. From Bactylocalyx Prattii,
Bowerbank, MS. X 176 linear. Pages 80 and
204.

277. Simple pisTuiiOSE siliceous fibre, spinulated.

From Farrea occa, Bowerbank, MS. X 108
linear. Pages 13, 80, and 204.

prehensile fibre.

278. cidarate prehensile fistulose siliceous fibre.

From a parasitical siliceo-fibrous sponge from the
south sea ; showing the position of the prehensile
organs at the base of the sponge. X 83 linear.
Page 80.

FIBRILATED FIBRE.

279. FiBRiLATED SPONGE FIBRE. From the skeleton of one

of the sponges of commerce. X 308 linear.
Page 73.

280. FiBRiLATED SPONGE FIBRE. From onc of the rigid

Australian sponges. X 175 linear. Page 73.



CELLULAR TISSUES.

281. A group of cells on a piece of an interstitial membrane

from Ecionemia acervuSy Bowerbank, MS. X 660
linear. Pages 81 and 88.

282. Cells on a portion of the interstitial membrane of

Halickondria niyricans, Bowerhmk, X 308 linear.
Pages 82 and 88.



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OF THE SPONGIADJi. 275

Fig.

283. Detached nucleated cells, from a new species of

sponge, from Freemantle, Western Australia.
X 308 linear.

284. A view of the upper stratum of cells in one of the Ovaria

of SpongiUa Carteri, Bowerbank. X 308 linear.
Por cellular tissue in Grantia see Figs. 312 and
314, Plate XXI, Pages 82 and 139.

SARCODE.

285. Represents a small piece of an interstitial membrane

from the honeycomb sponge of commerce in the
condition in which it came from the sea, exhibiting
the sarcode in situ and the imbedded semi-digested
molecules of nutriment. X 660 linear. Page 88.

INTERNAL AND EXTERNAL DEFENCES.

286. A small portion of a longitudinal section through the

cloaca of a specimen of Grantia tessellatay Bower-
bank, MS., showing the positions of the internal
defensive spicula, and their curvature towards the
mouth of the cloaca. X 108 linear. Page 29.

287. A portion of a thin section at right angles to the surface

of a specimen of Chalina seriata, Bowerbank, illus-
trating the mode of external defence by the pro-
longation of the radial lines of the skeleton. X 108
linear. Page 24.

288. A small portion of the kerato-fibrous skeleton of an

Australian sponge, showing the attenuato-acuate
entirely spined internal defensive spicula in situ
dispersed on the skeleton fibre. X 108 linear.
Page 31.

289. Verticillately spined internal defensive spicula dis-

persed on keratose fibres of the skeleton, from a
West Indian sponge. X 176 linear. Pages 23
and 125,



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276 ANATOMY AND PHYSIOLOGY

Fio.

290. Verticillately spined internal defensive spicula from a

keratose sponge, from the Wert Indies. Congre-
gated in fasciculi. X 175 linear. Pages 31 and
125.

291 . A small portion of Hymeniacidon Cliftoni, Bowerbank,

MS., exhibiting the membranous tissues of the
sponge enveloping the fibres of a Fueus; the defen-
sive spicula over the fibre being erect, whilst those
on the adjoining membrane are recumbent. X 108
linear : — a, one of the attenuato-cylindrical internal
defensive spicula. X 260 linear; i, a sm^ll portion
of the surface of the Fucus showing its cellular
structure. X 400 linear. Pages 31 and 125.

292. A portion of the reticulated specimen of the sponge

with the radiating fasciculi of spinulo-quateraate
internal defensive spicula in situ. X 108 linear.
See also Fig. 76, Plate III. Pages 23, 33, and 122;

293. A portion of the reticulated skeleton of Hymedesmia

Johnsoni, Bowerbank, MS., from Madeira, the fibres
armed with trenchant contort bihamate spicula.
X 50 hnear. One of the trenchant contort biha-
mate spicula, showing the cylindrical form at the
curves of the hook and the middle of the shaft, and
the trenchant edges of the rest of the inner sur-
faces of the spiculum, X 400 linear, is represented
by Fig. 1 12, Plate V. Pages 35 and 127.

294. A portion of the skeleton of Hydonema miradilis.

Gray, showing the mode of disposition of the mul-
tihamate birotulate and spiculated cruciform spicula
in the body of the sponge. In the collection at
the British Museum. X 50 linear. One of the
multihamate birotulate, X 175 linear, is repre-
sented by Fig. 60, Plate III, and Fig. 294, Plate
XVIII. Pages 37 and 127.

295. Represents a spiculated cruciform spiculum from

the same sponge, to show the relative prpportions
of the two forms of defensive spicula. X 175
linear. Pages 37 and 127.



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OF THE SPONGIADiB. 277

Fio.

296. Represents a small portion of the inner sur&ee of the

dermal membrane of Hymedesmia Zetlandica,
Bowerbank, showing the fascieulation of the simple
bihamate spicula, the equi-anchorate ones dispersed
singly on the membrane and the large attenuato-
aeuate entirely spined defensive ones in situ. X 308
linear. Pages 44 and 190.

297. A oircular group of ineqai-anchorate spicula, situated

on one of the interstitial membranes of Hymenia-
cidon lingtMy Bowerbank. X 308 linear. See
also Figs. 138, 147, &o., Plate VI. Page 49.

298. A small portion <rf the dermal membrane from Die-

tyocylindrm stuposua, Bowerbank, exhibiting the
number and position of the minute Sphero-Atellate
defensive spicula with which it is armed. X 308
linear. Page 109.

INTERMARGINAL CAVITIES.

299. A section at right angles to the surface of a branch

of Isodiatya simtdans, Bowerbank, exhibiting the
form and position of the intermarginal cavities.
X 108 linear. Page 101.

300. A section oi Halinchondriapanicea, Johnston^ showing

the intermarginal cavities at a, immediately beneath
thedermalsurface. Xl08Unear. Pages lOOand 195.
SOI. View of a small portion of the inner surface of the
dermal crust of Geodia Barretti, Bowerbank, MS.,
with two of the valvular membranes of the proxi-
mal ends of the intermarginal cavities : — a^ valve
closed ; b, a valve partly open ; c, c, the radii of
the pateAto-ternate spicula, imbedded in the tis-
sues, and forming the areas for the support of the
valvular terminations of the intermarginal cavities.
X 50 linear. — Longitudinal sections of two of the
intermarginal cavities are shown at a^ a, Fig. 354.
Plate XVIII.

Dermal membrane and inhalent pores, pages
111 apd 173.



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278 ANATOMY AND PHYSIOLOGT

PlO.

802. Two groups of inhalent pores in the dermal mem-
brane, situated immediately above the distal ends
of the intermarginal cavities of Geodia Barretti.
X 83 linear. Page 171.

303. A portion of the dermal surface of Halichondria pant-
cea, Johnston, showing the multispicular network
for the support of the dermal membrane and the
open pores in the areas. X 108 linear. Pages
108 and 195.

804. A small portion of the dermal membrane of Tethea

muricatay Bowerbank, MS., exhibiting the pores in
an open condition. X 108 linear. Pages 25 and
108.

805. A small portion of the same piece of membrane,

highly niagnified, to show the positions of the
elongo-stellate defensive spicula on the external
surface of the dermal membrane. X 183 linear.
Pages 25 and 108.

306. Represents the inner surface of the dermis of Dactylo-

calyx i'ra^/n, Bowerbank, MS., showing the manner
in which the apices of the radii of the temate spicula
forming the inhalent porous areas, are spliced on
each other to allow of the expansion and contrac-
tion of the dermal surface. X 108 linear. Pages
18, 19 and 101.

307. Represents a portion of the dermal surface of an un-

described sponge from the East Indies, having
numerous depressed porous areas furnished vrith
stomata-like protective organs, a, the protective
organ in a perfect condition ; i, having the pro-
tective organ removed to exhibit the deeply
depressed porous area. X 50 linear.

308. A portion of the sponge represented of its natural

size, with two large oscula and numerous inhalent
areas.

309. A small portion of the singlo-seried dermal spicular

network of hodictya varians, Bowerbank. X 108
linear. Page IDS.



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OF THB SPONOIADJE. ^79

310. A piece of reticulated kerato-fibroas tissue supporting

the dermal membrane of one of the species of the
common West Indian sponges of commerce.
X 108 linear. Pages 108, 109.

311. A small portion of the quadrilateral siliceo-fibrous

network of the dermis of Farrea occa, Bowerbank,
MS., showing the double series of entirely spined
spicular organs projected from its angles. X 108
linear. Page 104.

CILIA AND CILIARY ACTION.

312. A longitudinal section of the intermarginal cavities of

Grantia compreasa, showing the cilia and their
basal cells irt situ. X 500 linear. Pages 82, 105,
129, 130, and 163.

313. A view of a small portion of the inner surface of

Grantia compreaaa, exhibiting the oscula open,
and the appearance presented at their orifices by
the cilia within in action. X 500 linear. Pages
105, 129, 130 and 163.

314. Detached cilia and tessellated cells from the interior

of the intermarginal cavities of Grantia compreasa.
X 1250 linear, {a) A cilium in repose, {b) One
in the position of action, (c) Detached cells.
Pages 82 and 129.

REPRODUCTIVE ORGANS.

315. A small piece of a fibre of the skeleton of one of the

common Bahama sponges of commerce, with nu-
merous ova imbedded in its surface. X 400
linear. Pages 81 and 134.

316. A small piece of the fibre represented by Fig. 315,

exhibiting the varieties in form and proportion of
the ova. X 1250 linear. Pages 81 and 13*.



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280 ANATOMY AND PHYSIOLOGY

Fig.

817. An ovarium of SpongiUaJtuviatUi^m its natural state,
exhibiting the foramen. X S8 fineaiP. Page
182.

318. A perfect skeleton of an ovarium of Spongilla Jluma-

tiliSf Johnston, prepared irith nitric acid. X 183
linear. Pages 60 and 136.

319. View of a section, at right angles to the surface, of a

fragment of the skeleton of the ovarium of Spon-
ffiUafluviatilis, prepared with nitric acid, exhibiting
the relative positions of the spicula in the skeleton.
{a) A spiculum detached from the same ovarium
X 308 linear. Pages 60 and 136.

320. A skeleton of an ovarium of SpongUla lacustrisy pre-

pared with nitric acid, exhibiting the spicula in
situ and the foramen. X 183 linear. Pages 58,
60 and 137.

321. Two of the reticulated cases of the ovaria of Spongilla

Broumii, Bowerbank : — a, an empty case ; h, a
case containing the skeleton of an ovarium. X 50
linear. Page 139.

322. A reticulated case of an ovarium of ^pongitta reficu-

lata, Bowerbank. X 175 linear. Page 138.

323. Skeleton of an ovariiun of Spongilla reticulata,

Bowerbank, without its case, prepared with nitric
acid. X 175 linear. Page 138.

324. A perfect ovariiun of Diplodemia vesicula, Bower-

bank, and a portion of a second one, showing the
interior and the thickness of its walls in its
natural state. X 83 linear. Pages 60 and 140.

325. An ovarium of Geodia McAndretmi, Bowerbank, MS.,

in very nearly an adult state, showing the struc-
ture and position of the conical foramen for the
discharge of the ova, natural condition. X 183
linear. Page 142.



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0¥ THE SPONGIADJS. 281

Fig.

326. A small portion of the sarfaoe of a fully-developed

ovarium of Geodia MeAndrewii in its natural
state, showing the distal ends of the dpicula flat
and angular, and firmly cemented together.
X 308 linear. Page 142.

327. Two ovaria of GeoMa M^AnAremi, (a) containing

about the maximum of ova, (^) after a great part
of the ova have been discharged. X 108 linear.
Page 141.

328. A portion of a -section through nearly the centre of a

mature ovarium of Geodia MeAndrewii, showing
the radiation of its spicula from near the centre to
its circumference. X 308 lineM". Page 142.

329. A portion of a young ovarium of Geodia MeAndrewii,

with the distal ends of its spicula acutely teifmi-
tiated, and unconnected. X 308 linear. Page
142.

330. A mature ovarium of PAchymatiamct Johnstonia,

Bowerbank, exhibiting the Cuneiform spicula of the
foramen. X 308 linear. Page 148.

331. A young ovarium of Pachymatiemd Johnstcfnia in

course of development. X 308 liinear. Page
143.

332. A young ovarium of Pachymatisma Jolm^tonia in a

very early stage of development. X 308 linear.
Page 143.

333. Am ovarium from a sponge from Madeira closely

allied to Pachymatisma, exceedingly depressed and
much elongated. X 308 linear. Page 143.

334. A fragment of a similar ovarium to that represented

by Fig. 333, the fracture showing its extremely
thin condition. X 308 linear. Page 143.

335. A young ovarium of the same species as that repre-

sented by Fig- 333, in an early stage of develop-
ment. X 308 linear. Page 143.



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282 ANATOMY AND PHYSIOLOGT

Fio.

386. A reticulated ovarium in situ, on the fragment of a

sponge from Madeira. X 108 linear. Page
144.

387. A portion of the reticulated structure from an ovarium

of the same description as represented by Fig. 336.
X 308 linear. Page 144.

888. An ovum in course of development into -a young
sponge on the same membrane as that on which
the ovarium represented by Fig. 336 is seated.
X 108 linear. Page 144.

839. A group of ova or gemmules in course of develop-
ment into young sponges, found, with many others,
on the inner surface of a fragment of a large Pecten
from Shetland. X 108 linear. Page 146.

340. A small portion of the skeleton of Iphiteon panicea
in the Museum of the Jardin des Plantes, Paris, with
gemmules in situ. X 183 {Dactyloccdix, Stutch-
bury). Pages 146 and 204.

841. A gemmule detached fiovDL Iphiteon panicea. X 660
linear. Page 204.

342. A gemmule extruded from near the base of a speci-

men of Tethia lyncurium. on the distal extremity
of one of the skeleton fasciculi. X 50 linear.
Page 149.

343. Part of a group of internal gemmules in situ, on the


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