NO. 2247. SPONGES FROM NORTHWESTERN PACIFIC— HOZAWA. 531 



at a point a short distance from base, 80-120[jl long and 6-8ijl thick at 

 base. 



Gastral triradiates (c) sagittal. All rays slender, equally thick, 

 tapering to sharp point. Basal ray straight, much longer than 

 paired rays, 110-330[x long and about 8^ thick at base. Paired rays 

 nearly equal, slightly doubly curved, first forewards and then back- 

 wards ; 70-180pi, long and about 8[j- thick at base. 



Gastral quadriradiates (d) similar to gastral triradiates, except in 

 the presence of apical ray. Apical ray much shorter than facial 

 rays, slightly curved and gradualy tapering to sharp point, 40-80tx 

 long. 



Oxea at distal end of flagellate chambers generally slightly curved, 

 sharply pointed at both ends, about 80[x long and 4[x thick. 



Triradiates of oscular margin (e) sagittal. All rays nearly equally 

 thick, tapering from base to sharp point. Basal ray straight, slightly 

 longer than paired rays. Paired rays rather strongly divergent, dis- 

 tinctly bent at the middle of their length. In an example of the 

 spicule the basal ray measured 140[jl long and 6[j. thick at base, and 

 the paired rays 110[i. long and 6[Jt. thick at base. 



Quadriradiates of oscular margin (/) very strongly sagittal. 

 Basal ray straight, sharply pointed, slightly longer than paired rays. 

 Paired rays sightly curved at base, otherwise nearly straight, stand- 

 ing nearly at right angles to basal ray. Apical ray short, tapering 

 to sharp point. In a large example of the spicule the basal ray 

 measured 250[i. long and Q\k thick, and the paired rays 190[jl long and 

 8[x thick at base. 



Oxea of oscular margin (g) spindle-shaped, slightly curved, gen- 

 erally thickest nearer inner than outer end, about 370^1. long and 12pL 

 thick. 



Linear spicules of oscular ma'rgin straight or slightly curved, 

 sharply pointed at both ends, 240[ji. or more long and 2-4[jl thick. 



Locality. — Off Cape Eollin, Simushir Island, Kuriles (Station 

 4803,229 fathoms). 



4. HETEROPIA MEDIOARTICULATA, new species. 



Plate 84, fig. 7. 



Four specimens of this new species exist in the collection. They 

 are all of a closely similar appearance, being of a more or less bent 

 and laterally compressed tubular shape, attached by the narrowed 

 stalk-like base and showing at the somewhat contracted upper end an 

 csculum, which is surrounded by a trace of a collar. 



The largest specimen (pi. 84, fig. 7), which I make the type of the 

 species (Cat. No. 9186 U.S.N.M.), is nearly 40 mm. long and 10 mm. 

 broad in the broadest part, where the wall is about 2 mm. thick. The 

 oval osculum measures 3 mm. by 2 mm. across. The dermal surface 



