44 PROCEEDINGS OF THE NATIONAL MUSEUM vol.81 



very evident that microscleres are easily lost. I also merge Craniella^ 

 because of the difficulty of being sure whether one has a special type 

 of oxea in the ectosome. Lambe seems confident his species are so 

 supplied. There may be such in the California forms, but in such 

 small numbers that they are overlooked; further, rather smaller 

 oxeas do occur in the interior of the sponge most certainly ; and still 

 further, all the Tetilla megascleres are so easily broken that the 

 whole problem of identification of special categories is most diffi- 

 cult. From many published descriptions one can not be sure that 

 each Tetilla is not perhaps a Graniella. The two groups are so 

 similar in other respects that their combination seems to me most 

 advisable. Cinachyra, on the other hand, seems a well-marked 

 genus, and the interests of convenience would appear served by its 

 retention. This leaves about 71 species for Tetilla^ all of which are 

 very like one another. They have almost identical megascleres and 

 general plan. The principal differences are in ectosomal structure, 

 and in the microscleres. The latter are so small that some earlier 

 workers with poor microscopical equipment may have described 

 them inadequately. I find very few other species with the thin, 

 even ectosomal structure, and none with well-described microscleres 

 exactly like those of T. arb. 



Order HADROMERINA Topsent 



Family TETHYIDAE Gray 

 Genus TETHYA Lamarck 



TETHYA AURANTIA (Pallas) CALIFORNIANA, new variety 



Holoty'pe.—\}.^:^M.. No. 21495 ; B.M. No. 29.8.22.15. 



Type locality. — Pescadero Point, near Carmel, Calif., July 25, 

 1926, intertidal, collected by the author. Numerous other specimens 

 were examined, especially in the collections dredged by the University 

 of Southern California (U.S.N.M. Nos. 21390, 21411, and 21415), 

 from shallow water in southern California. There is frequently a 

 dense coating of diatoms and green algae over the surface of this 

 variety. 



Description. — Shape, hemispherical to ovate-stipitate. Size, up to 

 5 cm high, 3 cm in diameter. Consistency, moderately spongy. 

 Color in life, yellow; preserved, it is drab. Oscules, not evident. 

 Pores, not evident. Surface, superficially warty with mushroom- 

 shaped elevations about 2 mm high, crowded over the upper portion. 



Ectosomal specialization, cortical, about 1 mm thick. Endosomal 

 structure, fleshy, permeated by radiate fascicular tracts. Principal, 

 or ascending, tracts 250/i, to 8OO/1. in diameter, packed with spicules, 

 the more pointed end usually toward the surface. 



