140 
EURETID. 
skeleton-nets have been produced, are very distinct. In many places small 
hexactines, attached by the tip on one of their rays, arise vertically from the 
beams of the skeleton-net. 
I think there can be no doubt that these skeleton-nets belong to a euretid 
sponge, but since no loose spicules were found in them, I am unable to say to 
which genus they should be assigned. 
Euretid (?) from Station 4651. 
Plate 32, figs. 4-6. 
There are in the collection a fairly complete skeleton-net and three lamellar 
fragments of this sponge, all trawled off the coast of northern Peru, at Station 
4651 on 11 November, 1904; 5° 41.7' S., 82° 59.7' W.; depth 4064 m. (2222 f.); 
they grew on sticky, fine, gray sand; the bottom-temperature was 35.4°. 
The fairly complete skeleton-net (Plate 32 , fig. 4) consists of a dense basal 
mass with digitate processes, some of which are 10 mm. long and 6 mm. thick, 
from which arises a broad and low calyculate, funnel-shaped lamella. The margi- 
nal parts of the funnel are, for the most part, broken off. What remains of it is 
65 mm. in maximum transverse diameter. Proximally, where it arises from the 
basal mass, the lamella forming the funnel is about 1.5 mm. thick. Towards 
the margin it thins out to 1 mm. 
The skeleton-net of the basal mass is very dense and irregular. Its beams 
are mostly 15-100 /x thick, and its meshes 15-220 /x wide. The small meshes 
are round, the large ones triangular or irregularly square. The outer (dermal) 
zone of the skeleton-net of the funnel (Plate 32 , fig. 6) is irregular, composed of 
beams 20-180 /x thick, which enclose mostly triangular meshes up to 700 ,u wide. 
The inner, gastral zone (Plate 32, fig. 5) is more regular, but does not attain such 
a degree of regularity as is often observed in the corresponding zone of the skele- 
ton-nets of the Euretidae. It is chiefly composed of smooth longitudinal and 
transverse beams, but a fair number of usually spined, oblique beams also occur 
in it. The longitudinal beams are 50-100 /x thick, the transverse beams are 
sometimes 160 /x thick. The oblique beams are much thinner, usually only 
15-30 ix thick. The meshes are square or, less frequently, triangular. The 
square ones are usually somewhat irregular, not rectangular, 600-900 /x long, 
and 190-550 m broad. 
These skeleton-nets, which are similar to the ones from Station 4695, proba- 
bly belonged to a euretid. 
