398 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
2 min. high. Over most of the surface the conuli are arranged very distinctly in rows, which extend 
in parallel lines across the lamina; conuli close together, so that the rows form ridges, intervening 
depressions appearing as furrows 2 to 3 mm. wide. Over a part of the surface the conuli are irregularly 
distributed. Dermal membrane distinct and tough. No pores visible. A few small apertures, 
presumably oscula, 1 mm. and less in diameter, perforate the dermal membrane at the bottom of the 
furrows. Sponge very firm, flexible, and elastic. Color, light gray. 
Skeleton .• — Main skeleton consists of an irregular and dense reticulum of stout spiculo-fiber, pro- 
cesses from which extend up into conuli. Spiculo-fiber very variable in thickness, largely composed 
of horny matter, cored with (1) smooth styli 250 to 300 /i by 4 ft, tapering to sharp point, sometimes 
slightly bent. (2) Spined styli, 60 by 6 ft, echinating the fiber; also scattered in parenchyma. The 
shaft directly beneath spined head is smooth; rest of shaft spinose, terminating in smooth, tapering, 
sharp-pointed end (like corresponding spicule in Clathria clathrata Schmidt). (3) Styli similar to (1), 
but somewhat thicker and longer, lie freely scattered in parenchyma. (4) Stouter styli, 200 to 250 ft 
by 8 ft, also occur, both in parenchyma and in spiculo-fiber as well. (5) From projecting points of 
the skeletal reticulum multispicular bands of slender styli, similar to (1), radiate out toward the 
surface, expanding and becoming continuous with the dermal brushes. (6) There is a dermal crust, 
consisting of closely-set brushes of diverging styli similar to (1); pointed ends of styli, projecting a 
considerable distance beyond the surface. 
Microscleres: (7) Isochelte 12 to 14 ft long, abundant. (8) Toxas smooth, abundant. When 
small, 50 to 60 ft long, the shape is typical, although the curving is frequently such that the spicule 
does not all lie in one plane. All transitions are found between the toxas and long, hair-like oxeate 
spicules, up to 300 ft in length, which may be nearly straight or variously curved. Toxas and hair- 
like spicules frequently form loose bundles. 
Genus AGELAS Duchassaing et Michelotti (1864). 
“Of various form; with well-developed, horny fiber echinated by verticillately spined stylote 
spicules. No microsclera and no other megasclera” (Ridley & Dendy). 
Agelas schmidtii, n. sp. 
Siphonochalinopsis sp., O. Schmidt, 1880, p. 80. 
Station 6079, one specimen. 
Sponge body elongated, tubular, with a few short branches. Diameter of tube, for the most part, 
about 12 mm. ; thickness of tube wall about 2 mm. Total length of specimen 130 mm. Surface smooth 
and finely pilose. Consistency firm and, in the thinner places, parchment-like. Color yellowish-brown, 
with a tinge of washed-out red here and there. 
Oscula, 1.5 to 2.5 mm., are found at the ends of branches; also scattered over surface of the sponge 
body in general. In some cases osculum appears as a perforation of a smooth, depressed, membranous 
area, which may be rounded or irregularly elongate. In other cases osculum is not surrounded by such 
a membranous border. Membranous areas of this sort, which are not perforated, are scattered over 
the general surface. It seems probable that oscula may appear in such areas. 
Dermal membrane is pierced by the thickly scattered, radially projecting spicules, which echinate 
the superficial skeletal fibers. Membrane also thickly incrusted with the spores and hyphse of a 
fungus. No pores visible on outer surface of sponge. Membrane lining the tubular cavity exhibits 
scattered pores or pore areas; pores 20 to 40 ft diameter. Flagellated chambers, 16 ft diameter. 
Skeleton. — Skeleton consists of a reticulum of horny fiber, echinated sparsely in the interior, 
abundantly at the surface, with verticillately spined stylotes. Primary fibers, 50 to 60 ft thick, about 
500 ft apart; extending more or less radially, often very obliquely, from inner to outer surface; both 
echinated and cored by the stylotes, coring spicules abundant ih some places, scanty in others. 
Secondary fibers, 30 to 40 ft, echinated, but not cored, by stylotes, though a spicule, imbedded longitudin- 
ally, may here and there be found; forming with one another, and with the main fibers, irregularly 
arranged rounded polygonal meshes of variable diameter, commonly 140 to 250 ft. 
The stylote spicule, in addition to echinating and coring the horny fiber, is scattered freely in 
parenchyma. Spicule varies a good deal in size, from 200 by 8 ft to 90 by 4 ft ; base usually truncated, 
occasionally pointed; distal end tapering to sharp point; as a rule four spines in each whorl. Spines 
are relatively longer, and the whorls more conspicuous, in the smaller and medium-sized spicules than 
in the largest. 
