Antoine Guillemin Adolphe Brongniart.

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the species. The " crust," aeain, is charged with, or accom-
panied by, minute spicules of different forms, variously ar-
ranged according to the species, which will be found by-and-
by, as before stated, to yield the chief characters of our classi-
fication (fig. 1, ffy and fig. 2, b^ c). At the " aperture," of
course, these two coats are deficient, while the interior or chiti-
nous one is prolonged into it by a tubular extension, generally
in proportion to the thickness of the " crust" (fig. 1, A).

Meyen thought that the substance of the "crust" was
composed of " carbonate of lime having a cellular structure "
(No. 10. p. 154) ; but in no instance have I found it to effer-
vesce with acids, while, on the contrary, after boiling it for
some time in strong nitric acid it leaves a floccular residue,
which may be assumed to be a colloid form of silica, unless
it be undissolved tissue. As before stated, in some in-
stances the cell-structure, being comparatively large, is per-
fectly evident, while in others it is only resolvable under a
very high magnify ing-power (at least 450 diameters), when
it may be termed " microcell-structure," presenting under
ordinary circumstances a white granular appearance, which,
tilling up the intervals between the spicules, imparts to the
fully developed statoblast the light colour before mentioned.
It floats in water, and is very much like " pith," without
apparent cell-structure, is unaffected by liquor potassa, and
nntinged by iodine, while before the blowpipe it bums off
without leaving any perceptible residue. The floating-power
of this substance is very considerable ; for it keeps on the
surface the whole of the internal contents, which swell out
and sink to the bottom the moment they are liberated by sec-



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84 Mr. H. J. Carter on the

tion in water^ while the remnants of the crust themselves
continue to float with the greatest pertinacity. Still, although
in most instances where the statoblast is fuUj developed it
forms a thick coat, yet in others it can hardly be tracea even
under the microscope after the fully developed statoblast has
been mounted in balsam ; while it must not be forgotten that,
as its development is progressive, it may be as wntraceable at
an earlv period in one as in the other. •

Lastly, there is often a distinct layer of spicules which are
more like those of the skeleton than those of the statoblast, but
sufficiently differentiated by their peculiarities from both to
show that they do not belong to eitlier (PL VI. fig. 8, ?, n) ;
and these form a veiy distinct capsular covering to the stato-
blast, in which probably it was originally developed, and thus
separated from its neighbours.

Generallv the statoblasts are situated towards the base or
first-formed portions of the SpongiUaj either fixed to the object
on which the sponge may be growing, or more or less scat-
tered throughout its structure. The details of their development
may be found in the papers to which I have last alluded; while,
as this is also progressive, they often present themselves in a
collapsed hemispherical state, without the crust, when the chiti-
nous coat, being uncovered, gives them an amber colour, and
thus their appearance generally is that of a different kind; but, as
before stated, the statoblast when fully developed is, especially in
the fresh state, globular, and, in proportion to the thickness of
the crust, more or less white in colour. Yet there is a crustless
spherical form, wherein too the aperture may be multiplicate —
that is, double, triple, or even quintuple (rl. V.tig. b^ccccc)
— ^as first noticed in another species by Gervais (No. 7) ; with
which also there appear to have been statoblasts that contained
two or three others of the same kind presenting the same
structure, the same composition, and the same yellowish colour
(apud Johnston, No. 10, p. 154) ; so that, as before stated, the
statoblast, although generally globular or elliptical, may nave
these forms modified in a variety of ways, as indeed may be
seen in those which I have figured in Plates V. and VI.

Now, as the statoblast has so far been found in nearly all
the freshwater sponges that have been described, and never in
the marine ones, while- the form of the skeleton-spicule is not
only always acerate but almost always more or less alike in all,it
follows from the latter being of little or no specific value that
the statoblast, which is different in all, at least in the form of
its spicules, must become the basis of the most reliable classi-
fication ; and therefore I shall use its characters for what in
this respect I may hereafter have to propose.



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known Species <j/*Spongilla. 86

No attempt to classify the freshwater sponges had been
made up to the publication of the late Dr. J. E. Gray's " Notes "
in 1867 (No. 22, p. 491), when my dear old friend (alas I now
only dear to memory) made them the seventh order in his
" proposed " arrangement of the Spongida generally, under the
terms " Potamospongia,*' family " Spongilladae,'^' with the
following genera, viz. : — 1 . Ephydatia j 2. Dostlia ; 3. Me*'
tania ; 4. Acalle ; 5. Drulia ; 6. Eunapius ; and 7. Spongilla ;
adding Dr. Bowerbank's marine species Diplodemia as an
eighth genus — an incongruity arising from the misconception
of Dr. Bowerbank to which I have already alluded. If
Dr. Gray's "Notes" had been based on direct knowledge of
the species of Spongilla themselves, and not on Dr. Bower-
bank s *' Monograph " (No. 20), it might have been unneces-
sary now to propose a different arrangement. It is enough to
state of this " Monograph " that Dr. Bowerbank therein calls
the statoblasts " ovaries," and in speaking of them in Span -
gilla gregaria (No. 20, p. 15) thus expresses himself — " The
gregarious habit of these ovaries," &c. — to show the fallacies
that might arise from such loose phraseology. But setting
aside this and the like (for there is much to redeem it), I have
had before me, in addition to the publications under reference,
the actual specimens, while going through the late Dr. Bower-
bank's collections for the British Museum (where they now
are) ; and it has been from examination of these type speci-
mens, together with my own from the island of Bombay,
which were described, illustrated, and published long before
Dr, Bowerbank's "Monograph of the SpongillidsB, that I
have been induced to propose the following classification.

As may have been observed, in my " Notes introductory to
the Study and Classification of the Spongida," in 1875 (No.
27), I found it necessary to make the fresnwater sponges the
fifth family of my sixth order of the Spongida generally,
under the name of " Potamospongida," with a single group, at
present named " Spongillina." Hence so far they will stand
thus: —

Class SPONGIDA.

Order VI. HOLOEHAFHIDOTA.

Char. Possessiu]^ a skeleton whose fibre is entirely com-
posed of proper spicules bound together by a minimum of
sarcode. Form of spicule variable.



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86 Mr. H. J. Carter an the

Family 5. Potamospongida.
Freshwater Sponges.

Group 19. SpoiTGiLLiirA.

Char. Bearing seed-like reproductive organs called " sta-
toblasts."

Genera: 1. SpongiUa] 2. Meyenia', 3. Tubdla)
4. Parmula] 5. Vruguaya,

Spongilla.

Gen. char. Skeleton-spicule acerate^ smooth, curved, fusi-
form, pointed, sometimes more or less spined or more or less
inflated in the centre: sometimes accompanied bj flesh-
spicules. Statoblast globular, crust thick, thin, or absent
altogether, accompanial by or charged with minute acerates
(Pi. V. fig. 5, b by dy &c.), smooth or spined according to the
species, arranged tangentiallj.

* MimUe acerates Btnooth.

1. SpongiUa Carteriy Bk.

SpongiUa Carteriy Bk., No. 20; p. 31, pi. xxxviii. fig. 20 ; proviaioiially
8,friabiU$, Lam., No. 12, p. 83, pi. lii. tig. 3.

Massive, sessile. Colour greenish or faint whitish vellow.
Structure fragile, crumbling. Skeleton-spicule smooth, fusi-
form, curved, gradually t sharp-pointed. Statoblast globular;
aperture infundibular : crust composed of pyramidal columns
of dodecahedral or polyhedral cells, hexagonal in the section,
regularlv arranged one above another, in juxtaposition, per-
pendicularly to the outside of the chitinous coat on which they
rest ; surrounded hj a layer of minute, fusiform, curved, and
gradually sharp-pomted, smooth acerates (No. 19, pi. viii.
figs. 1-3).

Ih>c. Bombay.

2. Spongilla pauperciday Bk.
SpongiUa paupercuUiy Bk.^ No. 20, p. 32, pi. xxxviii. fig. 21.
Coating and branching. Skeleton-spicule curved, fusiform,

t ^Gh^dually," in contradistiiiction to ^abruptly" duirp-pointed
(See Pi. VI. figs. 14 and 16 respectively).



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known Species of Spongilla. 87

Bharp-pointed. smooth. Statoblast globular ; spictdes cunred,
fuflirorm, gradually shaip-pomted, smooth.

Loc. Water-pipes of Boston &c., U.S.

Obs. Mr. Thomas H. Higgin, F.L.S., of Liverpool, kindly
sent me a specimen from the same locality, viz. the water-
pipes of Boston, which, when examined, proved to have a
similar skeleton-spicule, among which there are a number of
minute, curved, rasiform, sharp-pointed acerates so like the
flesh-spicules of Spongilla lacustris that, in the absence of
statoblasts, I am led to consider it the same species ; and if I
am right, then the spicules of the statoblast snould be spined,
while those of S. paupercula were of the " same form as those
of the skeleton, but not more than half their size ; " so these
would be more like statoblast-spicules of S. Carteri. My
description of S. paupercula^ Bk., is an abbreviated one of
that given by Dr. Bowerbank himself {I. c).

3. Spongilla navicelloj Carter, n. sp.
(PI. V. fig. 4, a-g.)

Sponge unknown. Skeleton-spicule curved, fusiform,
smooth, gradually sharp-pointed. Statoblast adherent to the
twig on which the sponge had grown ; globoelliptical (fig. 4) ;
aperture terminal, infundibular (fig. 4, e) ; no apparent crust ;
cnitinous coat (fig. 4, c) encased with a dense layer of minute,
stout, short, thick, more or less curved, fusiform, smooth ace-
rates, variable in size, becoming so short internally (that is,
where they are in immediate contact with the chitinous coat)
as to be trapezoidal, or like a little boat or " cocked hat,"
according to the direction in which they are viewed j arranged
tangentially, crossing each other (fig. 4, d and g),

Loc. Biver Amazons.

Obs. A few of the statoblasts were found on a small twig
in company with S. reticulata^ Bk., and S. paupercula^ Bk.,
in the Bowerbank collection. They bear evidence of the
existence in the river Amazons of a species of Spongilla whose
entirety is as yet unknown ; and it is very probable that a
farther search there would find many such.

** Minute acerates epined,
4. Spongilla lacustris^ Linn.

SfxmgiOa Uumetrie, Bk., No. 20, p. 24, pi. xxxviii. fig. 14 j also No. 21,
vd il I c. and vol. L p. 342 ; also No. 25, pi. Ix. and No. 16, pp. 510,
611.

8, lacustris auctt

Branched ; branches long, round, and sharp-pointed. Colour



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88 Mr. H. J. Carter on the

dark brown. Structure fibrous. Skeleton-spicule (PI. VI.
fig. 14) curved^ fusiform^ gradually sharp-pointed^ smooth,
sometimes more or less spiniferous. Flesh-spicule thin,
curved, fusiform, gradually sharp-pointed, spined throughout.
Statoblast when fully developea globular ; aperture infundi-
bular; crust composed of granular cell-structure, charged
with more or less curyed, minute, stout, fusiform, sharp-
pointed acerates covered with stout recurved spines, arranged
tangentially or centrifugally, like the lines of a so-called
" engine-turned " watch-case.

Loc. England and Europe generally; North America;
Asia, Lake Baikal {Dybowatci).

5. Spongilla aJhaj Carter.

SpongiOa alba, Carter, No. 12, p. 83, pi. iii. fig. 4 ; also No. 20, p. 25,
pL xxxviii. fig. 15.

Massive, spreading, subbranched. Structure fra^e, to-
mentose. Colour whitish. Skeleton-spicule curved, msiform,
gradually sharp-pointed, smooth. Flesh-spicule thin, curved,
fusiform, covered with spines, longest in the centre, where
they are vertical and obtuse. Statoblast globular ; aperture
infundibular ; crust thick, white, composed of granular cell-
structure charged with minute, thict acerates, which are
curved, cylindrical, round at the ends, covered with spines
(especially about the extremities^ where they are longest and
much recurved) , arranged tangentially, intercrossing each other
like the lines of an engine-turned watch-case.

Loc. Bombay.

Obs, The spicules of the statoblast here, as well as in
Spongilla lacustrisj are considerably stouter, more curved,
cylindrical, and more coarsely spined than tlie flesh-spicules
of the sponge generally.

6. Spongilla cerebellatay Bk.
SpongUia oerebeUata, No. 20, p. 27, pi. xxxviii. fig. 16.

This Spon^Uoy which appears to me to be only a variety
of the foregomg species, differs from it chiefly in the absence
of the ** flesh-spicule," in addition to what Dr. Bowerbank has
mentioned (/. c).

Loc. Central India, Aurungabad.

7. Spongilla muUiforia *, Carter, n. sp.
(PI. V. fig. 5, o-rf.)

Massive, incrusting. Colour dark brown. Structure fra-

* muUiforUj with many doors or openingd (in allasion to the ploralitj
of the ** aperturee *').



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known Species o^Spongilla. 89

gile, fibrons, like that of 8. lacustris. Skeleton-spicule
curved, fusiform, gradually sharp-pointed, smooth, often
inflatea in the centre. Statoblast spherical (fig. 5) ; apertures
in plurality (one to five) (fig. 5, c c c cc), on a level with the
chitinous coat (fig. 5, a), as there is no apparent crust ; sur-
rounded by a layer of minute, curved, fosiform, sharp-pointed,
spinous acerates, which are in contact with the chitinous coat,
arranged tangentially (fig. 5, b and d) .

Loc. Chiluk-weyuk Lake, British Columbia, lat. 49^ IC N.,
lone. 121^ 22; W.

Type specimen in the British Museum, presented by
Dr. Lyall. Begister no. 64. 8. 11. 1-10 ; runnmg no. 239.

Obs. As the statoblasts, although very numerous, are all
empty, it is probable that the germinal matter has passed out
of them, and therefore that they are only the eflfete remains of
this organ, although still covered by the statoblast-spicules, as
represented in the illustration.

8. SpongiUa Lordii^ Bk.
(PI. VI. fig. 13, a-/.)
apangiOa LardU, Bk., No. 20, p. 28, pi. xxxviiL %. 17.

Sessile, incrusting reeds (fig. 13./) ; surface even. Struc-
ture fragile, crumbling. Colour light brown. Skeleton-spicule
curved, fusiform, graoually sharp-pointed, smooth, often inflated
in the centre. Statoblast hemispheroidal, flat bottle-shaped,
forming a single layer in juxtaposition round the reed, under-
neath ^e sponge, with the aperture upwards (figs. 13 and 13/):
chitinous coat hemispheroidal (fig. 13, a) ; aperture prolongea
from the summit by a short tubular extension (fig. 13, J, c) :
colour dark amber, followed by a thin granular crust charged
with small curved, fusiform, spined acerates, round at the
extremities, arranged tangentialhr (fig. 13, d and e).

Loc Lake Osogoos, Cascade Mountains, British Columbia.

Type specimen in the British Museum. Re^ster no. 68. 8.
17. 1-7 ; running no. 211. Presented by J. K. Lord, Esq.

9. SpongtUa nitensy Carter, n. sp.
(PI. V. fig. 3, or-ky and PI. VI. fig. 18.)

Form of sponge unknown to me. Structure reticulate;
fibre rigid, composed of bundles of spicules united by trans-
parent colourless sarcode, which in the dried state gives
It a hardness and vitreous appearance like that of Spongilla
coralltoideSy Bk. Skeleton-spicule curved, cylindrical, smooth,
sometimes very slightly inflated in the centre and at the ex-
tremitiesj which are round (PI. VI. fig. 18). Statoblast glo-



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90 Mr. H. J. Carter on the

bnlar (fig. 3) ; aperture infundibular (fig. d| g) ; crust com-

Eosed of pyramidal columns of dodecahedral or polygonal cells,
exagonal in the section, regularly arranged one above
another, in juxtaposition (fig. 3, d and t), perpendicularly to
the outside of the chitinous coat (fig. 3, c), on which, by the
intervention of a layer of the statoblast-spicules (fig. 3, e).
they rest, surrounded by a layer of minute, fusiform, curved
acerates thickly spined, especially over the ends, where the
spines are longest and recurved (fig. 3, i), arranged tangen-
tially (fig. 3, / ) ; the same kind of layer immediately round
the chitinous coat, where the spicules appear to be intermixed
with the lower cells of the crust, leaving the latter free between
the two (fig. 3, e).
Loc. Unknown.

Oba. Of this species I can state nothing more than that a
small fragment appeared in the Bowerbank collection labelled
" Spongiuaj new species, from the Jardin des Plantes." While
it affords another instance of the crust of the statoblast being
composed of apparently hexagonal cell-structure like that of
Spongilla Carteriy the rigidity and vitreous appearance of
the skeletal structure, if not the form of the spicule also, allies
it to SpongiUa corallioidesy Bk., which will be seen hereafter
to come from Uruguay. Finally, as this peculiar riridity of
the skeletal structure has in addition only been found in two
species of Spongilla (viz. 8. Batesii and 8. reticulcUay Bk.)
from the river Amazons, it n^&yhe assumed that 8. nitens also
comes from South America. The presence of a lajrer of sta-
toblast-spicules on the inside as well as on the outside of the
crust will be seen by-and-by to occur also in the statoblast of
Parmula {SpongiUa) Batesii.

Metenia*.

Chn. Char. Skeleton-spicule acerate, curved, fusificMin,
sharps-pointed, smooth, sometimes more or less spined, or
more or less inflated in the centre. Statoblast gfobular or
elliptical ; crust composed of the granular structure mentioned,
charged with birotulate spicules, t. «. spicular bodies which
consist of a straight shaft terminated at each end by a disk,
even or denticulated at the margin (PL V. fig. 6, A, &c.),
arranged perpendicularly around the chitinous coat, so that
one disk is applied to the latter, while the other forms part of
the surface of the statoblast (fig. 6, e).

* <' Meyema^ after Meyen, who first pointed out that the statoblast
was partly composed of birotulate or ampnidiscal spieulea {/. c,).



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known Species of Spongilla. 91

• Margin of disks even.
1. Meyenia erinaceus.
SpmgiUa erinaceus^ Ehr. apud LieberktihD, No. 15, p. 500.

Of tliis species Lieberktthn says, "Zeichnet sich durch
Kadeln aus, welche auf ihrer Oberflache mit kleinen Stacheln
versehen sind ;" but the spinous character of this spicule here
does not appear to be such a valuable character, in a specific
point of view, as the disks of the birotulate spicule of the
statoblast, which Lieberkuhn describes in the following page
to be without denticulation, and represents as umbonate with
even circular margin and short shaft (No. 15, Taf. xv.
fig. 31).

Loc, River Spree, Berlin.

Ohs. This sponge appears otherwise, i. e. in structure and
spiculation, to be like Meyenia fluviatilia. I do not know
where Ehrenberg has described it.

2. Meyenia Leidii.
SpanffiOa Leidii, Bk., No. 20, p. 7, pi. xxxtUI. fig. 2.

Thin, sessile, coating. Surface tuberculated, minutely
hispid. Structure friable, crumbling. Skeleton-spicule curved,
fusiform, abruptly sharp-pointed, sparsely spiniferous, becom-
ing mucii smaller and more spined round the statoblasts.
Statoblast globular, aperture infundibular ; crust composed oi
granular substance charged with birotulate spicules possessing
very short shafts and evenly margined smooth umbonate disks,
both of which have the margins more or less everted or turned
outwards (that is, from the statoblast), arranged perpendi-
cularly on the chitinous coat.

Loe. Schuylkill river, Pennsylvania.

3. Meyenia greffaria.
SpongiOa ffregarioj Bk., No. 20, p. 14, pL xxxviii. fig. 7.

Sponge unknown. Skeleton-spicule cylindrical, stout and
rather short. Form of statoblast not mentioned ; crust charged
with birotulate spicules composed of a short thick shaft termi-
nated at each end by a simple umbonate disk with even circu-
lar margin, arranged perpendicularly to the chitinous coat.
Spicules in the immediate neighbourhood of the statoblast
cylindrical, slightly curved, and abundantly spiniferous, vary-
ing considerably in size.

Loc. Biver Amazons.

Ohs. Having no specimen of this species to refer to, I ^ot
Mr. Stuart Rifley, F.L.S., of the British Museum, to examine
the mounted specimens of Spongilla gregaria a,nd o. reticulata^



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92 Mr. H. J. Carter on the

Bk.y for me, since, although I have taken my diagnosis from
Dr. Bowerbank's descriptions and illustrations {L c), still, as
the skeletal spiculation of the former is almost precisely that
of the latter, which covered the twig on which the stato-
blasts alone of 8. gregarta were found, to the extent of " five
inches," it seemed to be by no means impossible that the
spiculation of the two species might have been confounded.
Mr. Ridley's drawings are confirmatory of this possibility; and
thus the skeletal spiculation given by Dr. Bowerbank to 8.
gregarta becomes nearly identical with that of the foregoing
species, viz. 8. Leidity 6k. ; but while the ends of the spicules
are ahmptlj pointed in the lattery they are equally round in
8. reticulata and those stated by Dr. Bowerbank to charac-
terize the skeletal spicule of 8. gregarta.

Undoubtedly we have the same sparsely spined skeleton-
spicule becoming smaller and thickly spinea in the imme-
diate neighbourhood of the statoblasts in 8. Leidity 8. gre-
gariay and 8. reticulatay together with absolutely smooth
skeleton-spicules in all three, if those assigned to 8. gregaria
by Dr. Biowerbank be the right ones. Thus the skeletal
spicules and the spicules of the statoblasts in 8. Leidii tending
to the characters of those assigned to 8. gregariay in spite of
the roundness of the ends of the skeletal spicules in the latter,
seems to point out that the spinous element existed in both,
and that generally they are closely allied ; but, after all, it
does not satisfy our doubt as to whether the round-ended spicules
did not belone to 8. reticulata. Further observation is re-
quired to decide this.

** Margin of disks denticulated.

4. Meyenia fluviatilia.

SpongiUaJhmamiBf Bk., No. 20, p. 7, pi. xxxviii. fiff. 1 ; also No. 21,
VOL iL p. 339; vol. i. pL xxii figs. 817-319; and No. ^y voL iiL
pi. lix.

Sj^giUafluviatiUs auctt.

Massive, lobate. Structure ftiable, crumbling. Colour light
yellow-brown. Skeleton-spicule curved, iusiform, graduallv
sharp-pointed, smooth, often spined and often centriJly inflated,
Statoblast ^lobular; aperture infundibular; crust thick,
composed of the granular or microcell-substance, charged
with birotulates whose umbonate disks are deeply and irregu-
larly denticulated (PI. VI. fig. 11, a. i), arranged parallel to
each other and perpendicular to the chitinous coat.

Loc. Englana and Europe generally.

Ohs. Here, as elsewhere, in proportion to the thickness of
Ae crust is the len^ of the infundibular aperture, which is
partly lined by a tubular extension of the chitinous coat.



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Jcnovm Species q/*Spongilla. 93

Spongilla Meyeniy Carter.
SpongiUa Meyem, Carter; No. 12, p. 84 ; and No. 20, p. 10, pi. xxxviii.

Loc. Bombay.

Spotiffittajlumattlisy var. Parfitti^ Carter.

$y var. ParJUHy Carter, Ann. & Mag. Nat Hist. 1868,



▼ol. i. p. 247 ; and Bowerbank, 1870, No. 25, p. 2d8, pi kxxvi.
figs. 5-14.

Loc Kiver Exe, Devonshire.

Ohs. Having specimens of all three of these sponges now
before me, I cannot help thinking that the occasional diffe-
rences of spiculation in one may be seen in the other, and
therefore that S. Afeycn* and S.jluviatilisj var. ParfittidXQ mere
varieties of 8. fiuviatilts^Meyeniajluviatilis^ nobis. Of the
two specimens of S.JluvtatilisjVAV. Par/?Wt, that I have mounted,
nearly all the skeleton-spicules in one are smooth, add nearly
all those in the other are spiniferous, which shows what an
admixture of these two kinds of spicules may exist in Meyenia
JluvicUtlis. It is convenient here to allude to

SpongxUa aceptnferay Bk.
8p<mgiUa 9ceptifera, Bk., No. 25, p. 300, pi. Ixxxn. figs. 15-17.

Loc. Reservoir, Exeter.

Obs. This pretended new species is no '^ new species " at
all, but probably 8. fluviatUtSy as the statoblast would have



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