REVISION OF FRESHWATER SPONGES OF SPONGILLIDAE 93 



number of lobes and rays, their outer surface slightly but distinctly 

 granulated; length of shaft 36-52 /x, usually 45 n, diameter of rotules 

 23-27 IX, width of shaft 4-5 n. 



Gemmules moderately abundant in mature sponge, spherical, 

 ranging in diameter 410-480 fx; pneumatic coat well developed and 

 granular, consisting of minute subspherical air spaces; gemmoscleres 

 embedded in this coat in a single layer, their distal rotules not pro- 

 truding through the v/ell-defined outer gemmular membrane ; foramen 

 slightly elevated, but in height not reaching to level of outer gemmular 

 membrane, thus appearing slightly sunken. 



Distribution. — Known only from central and southern parts of 

 South America. 



Color in life. — Apparently not recorded. 



Discussion. — This is another spongillid of the E. ramsayi group of 

 species which displays somewhat slender and incipiently spined 

 megascleres and gemmoscleres of moderately stout shafts and greatly 

 different lengths. While the erection of E. facunda was undoubtedly 

 aided by the incorrect description of E. ramsayi by Haswell (1882), 

 the description of yet another sponge from South America by Weltner 

 (1898a) as a "variety" of E. ramsayi demonstrates the taxonomic 

 difficulties experienced by the describing author. The morphometric 

 reexamination of both E. facunda and E. ramsayi talaensis has shown 

 that these two sponges are identical in all major criteria, while the 

 affinities of the latter to E. ramsayi from Australia are remote. Pending 

 a further revision of this group, and particularly the collection of 

 additional material from South America, the specific status of E. 

 facunda is here retained, and at the same time E. ramsayi talaensis 

 relegated to its synonymy. 



Ephydatia fortis Weltner, 1895 



Plate 7, figures 8-10 



Ephydatia fortis Weltner, 1895, p. 141. — Annandale, 1911c, p. 53. — Gee, 1931e, 

 p. 38; 1931c, p. 71; 1932c, p. 30; 1932f, p. 507; 1932e, p. 526.— Arndt, 1932c, 

 p. 560. 



Ephydatia fortis var. hehridensis Gee, 1929a, p. 131; 1930a, p. 98; 1932c, p. 30. 



Ephydatia fortis var. vorstmani Gee, 1930a, p. 94; 1932c, p. 30; 1932f, p. 524. — 

 Arndt, 1932c, p. 562. 



Ephydatia fluviatilis var. etorohuensis Sasaki, 1940, p. 176. 



Meyenia fluviatilis var. etorohuensis Pennej^, 1960, p. 49. 



Meyenia fortis Penney, 1960, p. 50 (and varieties). 



Material. — Slides of syntypes of the nominal species, E. f. heb- 

 ridensis, and E.f. vorstmani (N. Gist Gee, USNM, AmstM). 



Description. — Sponge ranging from thin flat crusts to moderately 

 massive growths; surface even but hispid in flat specimens, possessing 

 irregular ridges in thicker forms, oscula few and inconspicuous; 



