45 FRISTEDT, SPONGES. 
specimen being 90 mm in length, about 60 mm in breadth and 
15 mm in thickness. The species is furnished with very firm 
fibres, filled up with the softer membranes. The upper surface 
is smooth and even, the lower uneven. 
Skeleton. The skeleton consists of acuate spicules, of 
small anchorate spicules, larger anchorate (= trenchant bil) 
spicules and very large bihamate spicules. 
The large acuate spicules (Plate 25, fig. 33) form the Gbres. 
They are sometimes slightly curved near the base; their length 
is 0,6 mm. 
The large anchorate spicules (Plate 25, fig. 34, 39) are Very 
variable in size and form. They are generally 0,1 mm in length. 
These spicules resemble very much those, named trenchant bih. 
by Vosme&er, Bowerbank and other authors. 
The small anchorate spicules (Plate 25, fig. 36, 37) are true 
anchorate ones; their length is only 0,03 mm. They are equi- 
ended and more numerous than the preceding kind. 
The bihamate spicules (Plate 25, fig. 38, 39) are very large 
and exceedingly numerous, the straight length between the 
points varying from 0,1 to 0,16 mm. Sometimes one of therends 
is divided into three small points. 
Colour. Light-grey with a tint of yellow, when dried or 
preserved in spirit. 
Habitat. East-coast of Greenland. depth 140 fathoms (581 5). 
Genus Forcepia Carter. 
Forcepia grenlandica n. sp. 
Plate 25, fig. 40—46. 
This species is represented by one specimen from Green- 
land, which is thickly incrusting a coral. The sponge is form- 
less, massive, the surface being uneven. Oscula are small, dis- 
persed. The consistency very fragile. 
Skeleton. 'The skeleton consists of spined acuate spi- 
cules, obtuse spicules, bihamate spicules, equianchorate spicules, 
and spined forcepiform spicules. 
