280 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



THENEA GRAYI, var. SULCATA, new variety. 



A small specimen from station 5178, about 10 mm. in diameter, 

 differs from the above in several points. 



The upper surface is smooth and not hirsute, showing plainly 

 under a lens the scattered pores. The under surface is well plastered 

 with sand grains, etc. 



The cloacal space is not covered in with a fenestrated membrane 

 but is quite open; in other respects like that of the type. The in- 

 halent area is expanded horizontally to such a degree that it ex- 

 tends more than halfway round the sponge in the shape of a long 

 groove, much as in a specimen of Theneamuricata figured by Vosmaer 

 (1882, pi. 1, fig. 1), or as in T. pendula Lendenfeld (1906, p. 210, 

 pi. 22, figs. 11, 12.) The inhalent membrane is also more finely 

 fenestrated than in the specimens of the type, the apertures ranging 

 from 75 to 150 pi in diameter. 



Several of the skeletal elements are smaller than those of the type. 

 Thus in the 4-rayed plesiaster the common length of ray is only 

 about 50 pi. In the metaster, with 6-7 rays, the common ray length 

 is 16-20 pi. The dichotriaenes in the fragment examined had short 

 deuteroclads, varying in length from 260 to 700 p.. 



Genus SPHINCTRELLA Schmidt (1870). 



Sjiliinctrclld Schmidt, 1870. p. 65. 



Massive, or lamellar, or sometimes incrusting forms. Without 

 specialized pore areas. With one or many cloacal depressions 

 fringed with long oxeas. into which numerous efferent canals open ; 

 cloaca may or may not be uniformly lined with a fenestrated mem- 

 brane. Radially arranged triaenes are typically present over the 

 whole or a part of the surface, but these may be absent. Similar 

 triaenes, or the calthrops form, usually occur in the interior. Small 

 oxeas (microxeas), varying considerably in size, represented some- 

 times by microtriads and microcalthrops, are scattered through the 

 body. 



SPHINCTRELLA BIFACIALIS, new species. 



Plate 87, fig. 1; plate 45, figs. 4, 6. 



Station D5543, one specimen. 



Sponge massive, somewhat flattened from above downward; at- 

 tached on the side to a coralline mass. The horizontal outline is 

 roughly triangular; horizontal diameter 80 to 90 mm.; greatest 

 vertical diameter 45 mm. One surface, doubtless the upper, bears 

 a large cloacal depression about 10 mm. deep with an aperture 35 

 by 12 mm. The remaining surface represents the latero-inferior 

 surface of the sponge. 



The upper surface is thickly covered with projecting megascleres, 

 protruding 2-3 mm. These prove to be long slender oxeas with a 



