142 CHONELASMA. 
These skeleton-nets may have belonged to a euretid sponge. They are 
similar to those described above from Station 4651. 
COSCINOPORIDAE Zittel. 
Lamellar, calyculate, or more complicated Hexasterophora consisting, if 
lamellar, of a simple plate; if calyculate or more complicated, of a rather thin 
wall enclosing a wide cavity. This plate or wall is traversed by straight, conical, 
blindly ending, sac-shaped afferent and efferent canals. With a firm supporting 
reticulate skeleton and uncinates and scopules. 
The collection contains one specimen of this family, which belongs to a 
species of Chonelasma. 
CHONELASMA F. E. Schulze. 
Funnel-shaped or lamellar Coscinoporidae. 
Chonelasma sp. 
Plate 32, figs. 7-9. 
There is in the collection a rather large skeleton-net of this sponge, collected 
in the Paumotu Islands at Station 3689 (A. A. 134) on 28 October, 1899; 18° 
06' S., 142° 24' W. ; depth 1476 m. (807 f.); they grew on a bottom of fine 
coral-sand and manganese nodules; the bottom-temperature was 37.6°. 
This skeleton-net (Plate 32 , fig. 7) is a curved plate, 92 mm. long, 51 mm. 
broad, and 9-1 1 mm. thick. The sponge to which it belonged may have been 
tubular or calyculate; probably it was of large size. The convex, probably 
outer (dermal) zone of the skeleton-net (Plate 32 , fig. 8 ) is on the whole smooth. 
It is composed of skeleton-net lamellae vertical to the surface, extending in- 
discriminately in all directions and crossing each other irregularly. These 
lamellae form a network, the meshes of which are represented by short vertical 
canals round or polygonal in transverse section and 0.5-2 mm. wide. The 
concave, probably inner (gastral) zone of the skeleton-net (Plate 32 , figs. 7, 9) 
has some outgrowths. Most of these are quite small. One is 8 mm. high. 
Apart from a curved, obliquely transverse band 3-5 mm. broad, where the net- 
work is so dense as to appear nearly solid to the naked eye, the zone of the 
skeleton-net bordering on this inner concave, probably gastral surface is com- 
posed of skeleton-net lamellae, vertical to the surface and extending longitudi- 
nally. These lamellae are about 0.7 mm. apart and connected by numerous 
