BULLETIN OP THE UNITED STATES PISH COMMISSION. 
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through a number of preparations, I have seen three such spicules. Their position possibly indicates 
that they are not foreign. (2) Small smooth oxeas (microxeas Sollas), 60 by 3 p, are abundant in 
the dermal membrane, where they are arranged tangentially; also scattered sparsely through interior. 
Microscleres: (3) Minute chiasters, 6 p diameter, incrusting the dermal membrane in great 
abundance. Similar but somewhat larger chiasters, 8 to 10 p diameter, are sparsely scattered through 
interior. 
In spiculation this species closely approaches Cdppatias (Stelletiriopsis) purpureus Carter (Carter 
1886, p. 459), from Port Western, South Australia. Carter’s description does not include details as to 
distribution of spicules. 
Family TETHYID/E Topsent. 
Body spheroidal or massive, with radiately arranged skeleton, and a more or less differentiated 
ectosome. When microscleres are present, the chief microsclere is some form of euaster. 
Genus TETHYA Lamarck (1815). 
Ectosome differentiated into a well-developed fibrous cortex. Megascleres are fusiform strongy- 
loxeas. Microscleres are euasters of two kinds (spherasters and chiasters). 
Tethya seychellensis (E. P. Wright) Sollas. 
Alemo seychellensis, E. P. Wright, 1881, p. 13, pi. i. 
Tethya seychellensis, Sollas, 1888, p. 127, pl.xiav, figs. 1-6. 
Ensenada Honda, Culebra, one specimen. 
Sponge more or less spherical, attached or free, surface conulose, eonules sometimes appearing as 
wide polygonal plates with denticulated margins. Oscules one or more in number; pores in sieves, 
situated in the depressions between the eonules, leading into extensive intercortical cavities (Sollas). 
Skeleton. — Megascleres. (1) Large strongyloxeas, 1.2 to 1.5 mm. long, with diameter 20 to 24 p. 
Similar smaller spicules of varying size down to 300 by 4 p are abundant. 
Microscleres. (2) Cortical spheraster, 40 p diameter. (3.) Somal chiaster, 8 to 10 p diameter. 
(4) Choanosomal aster, with a ray length 20 to 28 p. 
Tethya lyneurium (Lin.) Lajnarck. 
TWiya lyncuri am, Sollas, 1888, p. 435, pi. xr.m, figs. 15— IS; pi. xi.iy, figs. 17-19. 
Playa de Ponce light-house reef, three specimens; Ponce reefs, two specimens. 
Body spheroidal, attached. Diameter of specimens 15 to 22 mm.; small oscula present on some, 
absent on others. Buds on some of the specimens. Outer n on-fibrous part of cortex 800 p, inner 
fibrous part 650 p thick. 
Skeleton. — Megascleres. (1) Large strongyloxeas, 1.2 mm. by 20 p to 1.4 mm. by 28 p; oxeate 
end rounded, though often quite small. Essentially similar spicules of varying size, down to 340 by 
4 p, are abundant ; in the smaller forms the oxeate end is sharp-pointed. 
Microscleres. (2) Cortical spheraster, 72 p diameter. (3) Somal and choanosomal chiaster, 12 to 
16 p diameter. 
Genus TUBERELLA Keller (1880). 
Without a fibrous cortex, and without microscleres. Chief megascleres are fusiform strongy- 
loxeas, with small strongyloxeas at the periphery. 
Tuberella aaptos (O. Schmidt) Topsent. 
Ancorina aaptos, O. Schmidt, 1864, p. 33, Taf. iv, fig. 11. 
Suberites aaplus, Lendenfeld, 1896, p. 140, Taf. vn.xii. 
Tuberella aaptos, Topsent, 1900, p.285, pi. vm. 
Mayaguez Harbor, one specimen. 
Body is massive, higher than broad, 60 by 35 mm., attached below to coral; subdivided above 
into two short lobes, one with small (nearly closed?) terminal oseulum opening into a short axial 
cavity. Surface smooth or covered with short papillfe. Consistency firm and fleshy. Color: Surface 
of specimen very dirty; clean parts light brown. In a gross section peripheral layer is slate colored; 
interior light. 
