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6 1 8 C O L L E C T I O N S P E O M . T H E W E S T E R N I N D I A N O C E A N .
approximately cylindrical stems, 50 by 13 and 80 by 20 millim. respectively
in greatest beigbt and tbickness, arising close together
from a common rocky base. Tbe lower end of the larger one is
almost smooth for a distance of about 8 millim. ; the remainder, as
well as the whole of the smaller stem, is beset with small, slender,
wedge-shaped or pyramidal eminences, sometimes forked, 2 -3 millim.
high, about 2 millim. in diameter at tbeir bases and 2 -4 millim,
apart at tbeir summits ; tbe general surface between tbese processes
is honeycombed witb circular openings, -5 to 1-0 miUim. in diameter
and -25 to 1-0 millim. apart. Consistence rigid, slightly compressible,
tough. Colour very pale buff.
Skeleton typically Axinella-like ; fibre 3 or 4 spicules broad;
spicules united by dense, very pale yeUow horny fibre; axial
meshes close, -18 to -3 millim. across, the reticulation extending to
exterior of sponge. Sarcode pale yellow, subtransparent. Spicules
smooth acnate, curved more or less boldly at from one tbird to
ono half of the distance from tbe base ; base well rounded ; spicules
tapering to sharp points from about tbeir middle ; size *35 by -019
millim. In Lamarck’s specimen tbe surface-tufts are smaller and
only 1 -2 millim. apart, the sponge is more flattened than here, and
the spicules are slightly smaller, viz. -31 by -018 millim.
Hab. Darros Island, Amirante group, 2 2 fm s.
Distribution. King Island, Australia (Lamarck).
41. Axinella proliferans. ( P l a t e L III. figs. E, E ' ;
P l a t e LIV. fig. c.)
Erect, witb short flattened stem, expanding into flahellate fronds,
which towards tbeir ends proliferate into secondary flahellate frondlets
which assume a course parallel to th at of tbe main frond ; as the
latter is frequently plicate at its free margin, tbe aspect on looking
down at a large specimen from above is tb a t of a number of irregular
funnel-shaped ceUs, bounded by lamellar walls, roughened by very
numerous slashed ascending ridges. Surface of frond beset, at intervals
of about 4 millim., with sbarp ridges 3 -4 millim. high (5
or 6 miUim. near upper margin) ; the ridges notched at intervals of
about 3 millim. by ascending teeth, 1-3 millim. high, or altogether
replaced by longitudinal series of flattened, notched teeth.
Vents in spirit-specimen formed by circular openings, 1 -2 millim.
wide, leading obliquely downwards, scattered between the bases of
the laciniate surface-tufts and ridges of tbe sponges, chiefly near
tbe free margins of the latter. Texture in dry state tough, subelastic
; of stem and midribs firm, woody, of margins of fronds and
ridges flexible ; in spirit, all parts relatively more pliable. Colour
in dry state pale yeUow-brown to rufous-brown, in spirit pale salmon-
colour.
Cortical skeleton appearing on margins of surface-tufts and in some
places on face of frond as tufts composed of a few of spicule no. 1,
connected by tbeir bases ; in main stem consisting of confused linear
;V S i3 ï3â 3t!e?:
S P O N G I I D A .
spicular columns radiating horizontally from tbe axial skeleton, but
mucb disguised by crossing spicules, sometimes united into secondary
fibres. Axial skeleton—the longitudinal lines strong, but in basal
parts of sponge confused by close aggregation ; the axis of the fla-
bellate parts is composed, on the contrary, of a dense mass of horizontally
arranged spicules, from wbicb tbe short dermal tufts project
so as to appear on tbe surface of the sponge. Bases of spicules of
radiating lines and mucb of the entire axial spicular columns
enveloped in a tough transparent substance, amber-yellow in dry,
salmon-colour in spirit-specimens. ’
S p i c u l e s (1) Acuate, smooth, curved slightly but rather abruptly
at from one third to one half tbe distance from the b a se ; tapering
gradually from about middle, more rapidly from about three fourths
of length, to sbarp points, and sometimes slightly towards base;
base ratber squarely rounded; size -55 by -0 3 2 'to -045 miUim.’
(forms chief part of tbe axial and radial columns and tbe secondary
fibres). (2) Acuate, smooth, straight or slightly curved, tapering
gradually to fine points from about one fourtb of tbe length from
tbe apex; base well rounded ; size -5 to 1-8 by -015 to -02 millim.
(sparingly, in company w itb no. 1, in most p a rts ; especially, attached
to bases of radiating columns, and projecting outwards in a direction
parallel to them).
Hab. Providence Island, Mascarene group, 18 and 19 fms.; bottom
coral.
Two small specimens in spirit, one large dried dredged specimen,
and two medium-sized beacb-worn specimens represent tbe species ;
the largest measures 120 millim. (5 inches) in botb greatest beigbt
and lateral e x te n t; tbe stem is 20 millim. in greatest lateral by
8 millim. in greatest antero-posterior diameter. Tbe species bas
mucb of tbe external appearance of Spongia carduus, Lamarck, of
the Paris Museum, tbe spiculation of wbicb, however, refers it to
another genus. I t differs from all the species described by Schmidt
from European and W.-Indian seas in the absence of an acerate
spicule; in tbe great stoutness of the main acerate it approaches
A . mastophora p i tb at author, from Elorida. In general habit it
resembles Acanthella ratber than Axinella, but wants tbe long
undulating cylindrical spicule hitherto found in species of th at
genus; it appears_doubtful whether tbe existence of such species
as tbis should not induce us to unite tbe two genera. I bave been
unable to identify it with any described species; tbe large stout
acerate appears to be tbe most distinctive characteristic.
LEUCOPHLOEUS.
Carter, Ann. ^ Mag. N. H 1883, xii. p. 323.
_ In its affinities tbis genus appears to be Axinellid ; it is distinguished
from Axinella, s. str., by its loose yielding texture, tbe
sloeleton-fibres being loosely united, but containing a dense kerétose
■ ri