ROSSELLINAE. 93 



The largest fragment (Plate 32, fig. 10) is apparently part of a stalk. It is 

 99 mm. long., 12 mm. thick at the base, and 17 mm. at the upper end. At the 

 thinner, probably the lower, end it is solid for a distance of 18 mm. ; farther on it 

 is tubular. The tube thus formed widens above in a calyculate manner and has 

 a wall about 3 mm. thick. The two other fragments which are 57 mm. and 49 

 mm. long respectively are curved lamellae, also about 3 mm. thick. They 

 apparently formed parts of lamellar, calyculate sponges. 



The skeleton-net (Plate 32, figs. 11, 12) consists of main-beams 100-300 n 

 thick, which extend obliquely longitudinally or, more rarely, transversely. These 

 main-beams form more or less distinct bundles, within which they lie quite close 

 together and connected by numerous short, somewhat thinner, transverse beams. 

 The bundles are on an average about 0.6 nmi. thick and form a network with 

 elongated spindle-shaped meshes, usually 0.4-0.6 mm. broad and 1-3 mm. long. 

 The indi\ddual beams are either smooth or bear a few scattered, low, blunt 

 spines. Here and there the spines are more crowded. 



In some respects these specimens resemble the skeleton-nets of the stalk 

 and the lower parts of the body of caulophacid hexactinellids, and they may have 

 formed parts of such. 



ROSSELLIDAE (F. E. ScmiLZE) Ijima. 



Hexasterophora with special diactine to hexactine dermal, and pentactine 

 hypodermal spicules, which latter sometimes project a considerable distance 

 beyond the surface, their lateral rays then forming a veil covering the sponge. 



The collection contains twenty-two more or less complete specimens and 

 twelve fragments of this family. 



F. E. Schulze ^ distinguishes three subfamilies in this family, all of which 

 are represented in the collection. 



Rossellinae F. E. Schulze. 



RosseUidae without discoctasters and plumicomes. 



The collection contains twenty more or less complete specimens and twelve 

 fragments of specimens belonging to this subfamily. All are referred to the 

 new subspecies Bathydorus laevis spinosissimus. 



' F. E. Schulze. Hexactinellida. Ergeb. Deutsch. tiefsee-exped., 1904, 4, p. 176. 



