Sollas — On Tetractinellid Sponges. 185 



T. fenestrates, 0. Schmidt. 



T. delicata, sp. n. — Sponge, small symmetrical, a conical upper 

 half, sharply defined from a hemispherical lower half ; upper 

 surface hirsute; oscule apical; flagellated chambers, 0*087 by 

 0-067 mm. Spicules — (1) acerate, 6*3 by 0-044 mm. ; (2) por- 

 rectate forks, shaft, 4*10 by 0*02 mm. ; arms, 0*35 mm. long ; 

 (3) bifurcate forks, shaft, 4-82 by 0*065 mm. ; primary rays, 0*143 

 by 0*06 mm. ; secondary rays, 1*07 by 0-06 mm. ; (4) somatic 

 anchors, shaft, 0*954 by 0*008 mm. ; rays, 0*075 mm. long ; 

 spread, 0*876 mm. ; (5) anchoring spicules terminate in rounded 

 club-like heads ; shaft, 5*35 by 0*04 mm. ; head, 0*0645 mm. 

 wide ; (6) calthrops few, small, tending to a spiral form ; rays, 

 0-08 by 0*008 mm. ; (7) spini-spirulse, shaft short and straight, 

 spined at the ends ; total length, 0*04 mm. Greyish- white. 



Habitat— Station, 147., lat. 46° 16' S. ; long. 48° 27' W. 

 1600 fms. 



T. wrightii, sp. n. — Sponge depressed, a flat or obtusely conical 

 upper surface, bearing the oscule ; and a flat base ; margin more or 

 less lobate ; equatorial recess discontinuous ; forming a number 

 of circumscribed poriferous areas. Oscular and poral areas not 

 defended by projecting spicules; rootlets absent. The flat cake- 

 like form of the sponge is characteristic. 



Habitat— Station 302, lat. 42° 43' S. ; long. 82° 11' W. 

 1450 fms. 



Grenus 2. Kormania. — Sponge without specialized porous areas, 

 like those of Thenea ; triana ; simple forks, without anchors ; 

 quadriradiate spicules, as well as calthrops, occur in the choano- 

 some ; mesoderm of the choanosome a collenchyme ; canal' system, 

 eurypylous. 



Normania schulzii, sp. n. — A plate-like erect sponge, bearing 

 pores on one surface, and oscules on the other ; distinguished from 

 Normania crassa by the size of its spicules ; the acerates, 3*57 

 by 0*071 mm. ; the forks, shaft, 0-714 by 0-071 ; arms, 0-357 mm. 

 long. 



Habitat.— Station 150 ; lat. 52° 4' S. ; long. 71° 22' E. 150 fms. 



N. crassiuscula, sp. n. — A plate-like sponge^similar in character 



