Sollas — On Tetractinellid Sponges, 183 



traverse it transversely ; the innermost layer of the cortex is free 

 from spicules ; the cortex is not excavated by intercortical cavities ; ' 

 the oscules and pores are confined to special flasked-shaped recesses ; 

 the mouth of each flask is sphinctrate ; the walls are perforated by 

 pores which communicate with the incurrent or excurrent canals, 

 as the case may be ; the mesoderm of the choanosome is a granular 

 collenchyme ; the canal system is eurypylous. 



Cinochyra barbata, sp. n. — Sponge sub-spherical or sub-cylin- 

 drical, seated on a dense mass of its own anchoring filaments. 

 Oscules and pores as in genus. Spicules — (1) fusiform acerate, 

 8*03 by 0-71 mm. ; and a smaller acerate of the cortex, 0892 by 

 0-0355 mm. ; (2) forks, a fusiform shaft, 13-21 by 0-0296 mm.; 

 rays, 0*178 mm. long ; (3) trichite forks, shaft, 0-13 by 0-004 mm. ; 

 rays variable in length, one longer, about 0-03 mm. long ; two 

 shorter, about 0-016 mm. long ; (4) anchors confined to the lower 

 part of the sponge ; shaft from 20-0 to 40-0 by 0-024 to 0*03 mm. ; 

 rays, 0*103 by 0-016 mm. ; spread 0-118 mm. ; (5) arculi and 

 sigmellee, about 0*0156 mm. long. ; (6) globules, 0-0535 mm. in 

 diameter. 



Habitat. — Kerguelen, 10 to 150 fms. 



Family 2. THENEID.E. 



Grenus 1. Thenea. — Sponge of symmetrical form, with special- 

 ised poriferous areas. The triana are bifurcated forks, with long 

 secondary rays ; and anchors. 



Thenea muricata, Bwk. — Occurs in the northern regions of the 

 North Atlantic, not present in the Challenger collection. 



Thenea schmidtii, sp. n. — Sponge similar to T. muricata, Bwk., 

 but distinguished by the large size of its calthrops spicules, and by 

 the comparative thinness of the collenchymatous layer about the 

 canal walls ; the rays of the calthrops from 0*175 to 0-205 mm. 

 long. 



Habitat— Station iv., lat. 36° 25' N. ; long. 8° 12' W. ; 600 

 fms. ; station 73, lat. 38° 30' N. ; long. 31° 14' W. ; 1000 fms. ; 

 and (O. Schmidt) Florida, 198 fms. 



T. grayi, sp. n. — Sponge with a more or less flattened summit 

 and rounded base, which in young forms is hemispherical. Oscule, 



