140 EURETID. 



skeleton-nets hsive 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 40G4 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 mai'gin it thins out to 1 mm. 



The skeleton-net of the basal mass is very dense and irregular. Its beams 

 are mostly 15-100 ^ thick, and its meshes 15-220 fi 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 ^ thick, which enclose mostly triangular meshes up to 700 fx. 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 ^ thick, the transverse beams are 

 sometimes 160 n thick. The oblique beams are much thinner, usually only 

 15-30 M thick. The meshes are square or, less frequently, triangular. The 

 square ones are usually somewhat irregular, not rectangular, 600-900 fi long, 

 and 190-550 m broad. 



These skeleton-nets, which are similar to the ones from Station 4695, proba- 

 bly belonged to a euretid. 



