SILICIOUS AND HORNY SPONGES WILSON. 459 



2. Dichotriaenes. The claclomes (pi. 50, fig. 11) lie in the dermal 

 membrane; primary clad 30-35 by 17-21 [/., secondary clads 100 _ 130 

 [x long. Rhabdome 105-125 by 14-21 p., pointed at the end, some- 

 times bluntly. Spicules are common in which one or a few of the 

 terminal clads are not of full size, sometimes slightly deformed. The 

 trichotriaene variation, found in Jereopsis superstes (Sollas), was 

 not observed. 



3. Oxeas. Small oxeas, 100-180 by 4-5 [x, occur alongside the rhab- 

 domes of the triaenes, projecting slightly from the surface. Larger 

 oxeas, about 240 by 5 jjl, occur in the ectosome apart from the 

 triaenes, but radial to the surface, singly or in bundles of a few. 

 These and the small forms are fairly abundant round the oscule. 



A few large oxeas, possibly foreign, were observed; they meas- 

 ured 400-600 by 16-24 \l, with blunt ends. 



4. Streptasters. The spicules of the interior are amphiasters (pi. 

 50, fig. 6, a) or amphiasters that approach the spiraster type (fig. 

 6, b). In the former, the total length of which is about 24 pi, there 

 are about four long, slender rays at each end of the short slender 

 axis. In the latter class of amphiaster the total length is about 20 

 p, the axis is stouter, and the rays somewhat shorter, stouter, more 

 numerous and more distributed along the axis. 



The streptasters of the dermal membrane (pi. 50, fig. 6, c) are 

 spirasters about 16 y. long. Kays shorter and blunter and more 

 numerous than in the spicules of the interior, and scarcely or 

 not at all grouped at the ends of the axis. All classes of strept- 

 aster are minutely roughened. 



Holotype.— Cat. No. 21271, U.S.N.M. 



Family COSCINOSPONGIIDAE. 



Comllistidac Sollas, 1888, p. .301. 

 Coscinospoitgiidac Lendenfeld, 1903, p. 135. 



With ectosomal triaenes which may be dichotriaenes, phyllotri- 

 aenes, or discotriaenes. Desma monocrepid and tuberculate. 



Lendenfeld accepts the family in Sollas' sense but restores Cos- 

 cinospongia Bowerbank, not recognized by Sollas, into which he 

 merges two of the genera used by Sollas, CoraUistes and Heterophy- 

 mia, thus making it necessary to change the family name. By other 

 mergings Lendenfeld still further reduces the number of genera em- 

 ployed by Sollas. 



In this family there have been described since Lendenfeld's syn- 

 opsis (1903) Coscinospongia gracilis Lendenfeld (1906, p. 354), 

 Macandrewia auris Lendenfeld (1906, p. 358), M. robusta Topsent 

 (1904, p. 61), M. ramosa Topsent (1904, p. 62). 



