Sollas — On Tetractinellid Sponges. 197 



daster, centrum small, rays conical pointed, or rod-like truncated, 

 0*016 to 0*0193 mm. in diameter. Colour, purplish white. 

 Habitat. — Bahia. 7 to 20 fms. 



Cydonium magellani, sp. n. — Sponge large, attached ; surface 

 hispid. Spicules— (1) acerate, 3*93 by 0*052 mm., to 2*71 by 

 0-058 mm. ; (2) fork, shaft, 3*93 by 0-064, to 4-82 by 0-09 mm. ; 

 arms bifurcate; primary rays, 0-13, secondary, 0-275 mm. long; 

 (3) anchor, shaft, 7 - 4 by 0*02 mm. ; rays, - 15 mm. long ; (4) glo- 

 bate, spherical, depressed, 0-123 by 0-103 mm. ; (5) ectaster ; a 

 fairly large centrum, numerous rod-like rays, 0*0118 mm. in 

 diameter ; (6) endaster, a globo-stellate, 0*217 mm. in diameter. 

 Habitat. — Stations 308 and 311. 175 and 245 fms. 



Cydonium Mrsutus, sp. n. — Sponge irregular lobate; surface 

 hispid, spicules projecting 8 or 9 mm. beyond it, cortex thick. 

 Spicules — (1) acerate, 4*5 by 0*06 mm. to over 9*0 by 0*032 mm.; 



(2) fork, shaft over 4*46 mm. long by 0*084 to 0*05 wide ; arms 

 bifurcate, primary arms, 0*13; secondary, 0*35 mm. long; 



(3) second form of fork, shaft long, diameter, 0*2 mm., arms 

 simple 0*13 mm. long; (4) anchor, shaft, long, 0*018 mm. in 

 diameter; rays, 0*036 mm. long; (5) globate, a flattened prolate 

 ellipsoid : 0*306 by 0*245 by 0*161 mm. ; (6) ectaster, a small 

 centrum, and blunt conical rays, 0*012 mm. in diameter ; (7) en- 

 daster, a small centrum, and a few slender conical rays, 0*02 mm. 

 in diameter : a small globo-stellate is present, but does not belong 

 to the sponge. 



Habitat.— Station 192 ; lat. 5° 49'15" S. ; long. 132° 14' 15" W. ; 

 140 fms. 



Synops vosmaeri, sp. n. — Sponge cylindrical, a cup-shaped 

 depression at the summit, erect, attached, oscules confined to the 

 summit; pores in sieves on the sides, roofing incurrent chones. 

 The ecto-cortex contains ectasters scattered throughout it; the 

 globate layer is thin, and the fibrous layer remarkably thick. 

 Spicules — (1) acerate, from 1*3 by 0*016 to 1*7 by 0*008 mm. ; 

 (2) acerate of the cortex, 0*3 by 0*004 mm. ; (3) fork, shaft, 1*1 

 by 0*039 mm. ; arms, simple, 0*29 mm. long ; (4) globate, small, 

 spherical, 0*04 mm. in diameter ; (5) ectaster, a small centrum, 

 short spines, with rounded ends, 0*004 mm. in diameter; (6) en« 



