400 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Genus AXINELLA 0. Schmidt (1862). 
“Sponge typically ramose, but may be massive. Skeleton fiber plumose. Megasclera stylote 
and sometimes oxeate. No microsclera.” ( It. & D.) 
Axinella reticulata Ridley & Dendy. 
Axinella reticulata Ridley & Dendy, 1887, p. 184, pi. xxxvn, figs. 4, 4a. 
Station 3079, one specimen. 
Specimen consists of a cylindrical, upright lobe, 80 mm. by 20 mm., rising from an enlarged and 
broken basal part. Dermal membrane minutely reticulate, containing a few scattered spicules, and the 
brushdike ends of the radial fibers. Reticulation of dermal membrane (best seen with lens, surface 
under fluid) not due to skeleton, but to thickenings of dermal membrane itself. Rather numerous 
oscula, 2 to 3 mm. diameter, distributed over surface, not as in type at summits of oscular tubes. 
Surface beset with numerous small conuli. Consistency firm, sponge almost incompressible. Color, 
salmon-pink (type, pale yellow). 
Skeleton . — “There is an extremely irregular reticulation of scattered spicules, among which one can 
distinguish rather loose plumose fibers running more or less vertically towards the surface” (R. & D. ). 
In the Porto Rico specimen there are longitudinal fibers, from which radial fibers curve outward 
toward surface. Fibers are loose, but coarse and distinct, except in regions where the scattered spicules 
are crowded. Spicules in the fibers very abundant. 
Spicules. (1) Chief spicule is a stout, smooth, slightly curved style, 340 by 16 ft (type, 450 by 
20 ft), usually with a bend toward the base. (2) Smooth, slightly curved oxeas, of about same size as 
the styles, are infrequently met with. 
Genus THRINACOPHORA Ridley (1885). 
“Sponge ramose, with a dense central axis of spiculo-fiber; megasclera styli and (or) oxea, and 
(in some species) cladostrongyla. Microsclera present in the form of trichodragmata.” (R. & D.) 
Thrinacophora spinosa, n. sp. 
Station 6072, three specimens. 
Sponge body cylindrical, erect, and branching from the base. Branches lateral, but all more or 
less parallel; tapering gradually toward the end; after forming, may again fuse with one another. 
Surface covered with closely set, stiff, conuli, 2 to 3 mm. long, and about 2 to 3 mm. apart; each taper- 
ing distally to a point; and all pointing outward and more or less upward. A few divergent spicules 
(spicule 1), about equal in size, in number up to 5 or 6, protrude from apex of each conulus. Oscula, 
2 mm. and less in diameter, are scattered, not abundantly, over surface of branches. Common 
diameter, excluding conuli, about 7 mm; height of largest specimen 220 mm. Color, brown. 
Between axial core and dermal membrane are fairly numerous subdermal spaces and canals. 
Skeleton . — Skeleton of axial core consists of compact mass of spiculo-fiber; from which bundles 
radiate obliquely upward and outward into the superficial conuli, as may best be seen in a macerated 
sponge. Spiculo-fiber consists of abundant spongin, in which some of the spicules are completely 
imbedded, while most are only partially imbedded. Spiculo-fiber of axial core forms a network; 
meshes more or less rounded in transverse section, elongated in longitudinal section. 
Characteristic spicules of the spiculo-fiber are (1) style, about 1,100 by 10 to 12 ft, smooth and 
evenly rounded at the base, tapering to a point, slightly curved. (2) Oxea, about 250 by 8 //, 
smooth, tapering to not very sharp points, slightly curved or bent at the middle. Smaller forms of 
these two spicules are fairly common, style measuring often only 800 by 8 ft, oxea 200 by 6 A less 
characteristic spicule is (3) style, very slender and of very variable length; often 800 to 1,100 ft by 
5 /t ; much smaller forms, down to 400 n by 3 to 5 ft, also common; frequently somewhat curved in an 
undulating fashion. 
Microsclera. In the dermal membrane (4) trichodragmata are abundant; bundles measuring 
about 120 ft by 8 to 12 ft. I have not been able to find them in the interior of the sponge, but this 
part of body is badly macerated, 
