32 U.S. NATIONAL MUSEUM BULLETIN 2 72 



Distribution. — Known only from the United States and Canada 



Color in life. — Light gray to brown. 



Discussion. — E. igloviformis is a well described and equally well- 

 known species, which can be easily separated from its closest 

 congener, E. fragilis, by the structure of the megascleres, the do me- 

 shaped arrangement of gemmule groups, and by the inward opening 

 foraminal tubules. 



Jewell, in Ward and Whipple (1959), relegated this species to a 

 synonym of S. mackayi Carter without giving any reasons for her 

 decision. The latter species is poorly represented in the material for 

 this study and cannot be fully compared with the material of E. 

 igloviformis. Even though the spicular components of S. mackayi show 

 certain affinities to those of the species discussed, it could well be 

 possible that the differences discernible are caused by an ecomorphic 

 malformation of the former, resulting in freak scleres. Until more 

 material of S. mackayi becomes available, it is thought advisable to 

 retain the specific status of E. igloviformis. 



Eunapius geminus (Annandale, 1911) 



Plate 2, figures 12, 13 



Spongilla gemina Annandale, 1911c, p. 97; 1918a, p. 211. — Gee, 1931e, p. 39; 

 1932c, p. 38.— Penney, 1960, p. 19. 



Material. — Slides of syntype (N. Gist Gee). 



Description. — Sponge, according to Annandale (1911c), forming 

 small and shallow cushions of circular outline; surface minutely hispid, 

 oscula numerous but minute and inconspicuous; dermal membrane 

 closely adhering to symplasm. Skeleton consisting of a close and reg- 

 ular network at the base, becoming more diffuse in upper parts. 

 Consistency of live sponge moderately hard but friable. 



Megascleres slender, fusiform amphioxea, entirely smooth; length 

 range 175-240 n, width range 6-11 n. 



Microscleres absent. 



Gemmoscleres slender and cylindrical am phistron gyles or amphi- 

 oxea, irregularly covered with minute straight spines; length range 

 75-105 fi, width range 2-4 [x. 



Gemmules characteristically bound together in pairs, irrespective 

 of their location, diameter of inner gemmidar membrane 180-220 fi; 

 pneumatic layer only moderately well developed, consisting of a thin 

 coat of large polygonal air spaces; gemmoscleres embedded in this 

 coat tangentially ; foramen produced into a long curved tube, opening 

 outward. 



Distribution. — Known only from the type locality in India. 



Color in life. — Gray to brown (Annandale). 



