REVISION OF FRESHWATER SPONGES OF SPONGILLIDAE 83 



Meyenia fluviatilis var. mexicana Potts, 1887, p. 219. 



Ephydatia goriaevii Swartschewsky, 1901, p. 344. — Gee, 1931e, p. 39. 



Ephydatia fluviatilis var. capensis Kirkpatrick, 1907, p. 524. — Weltner, 1913, 



p. 475.— Annandale, 1914, p. 246.— Gee, 1931e, p. 35. 

 Ephydatia fluviatilis var. syriaca Topsent, 1910, p. 47. — Annandale, 1913a, p. 59; 



1915c, p. 473; 1918a, p. 212. 

 Ephydatia fluviatilis var. hirnalayensis Annandale, 1910d, p. 198; 1918a, p. 212. — 



Gee, 1932c, p. 30. 

 Ephydatia fluviatilis var. intha Annandale, 1918b, p. 76; 1918a, p. 212. 

 Ephydatia fluviatilis var. chui Gee, 1926c, p. 110; 1926a, p. 184; 1927a, p. 7; 



1927b, p. 63; 1928, p. 225; 1930d, p. 369; 1930b, p. 170; 1931e, p. 35; 1932c, 



p. 30.— Rezvoj, 1930, p. 175. 

 Ephydatia fluviatilis var. teberdana Rezvoj, 1928, p. 228. 

 Ephydatia fluviatilis var. hastifera Rezvoj, 1930, p. 185. 

 Ephydatia fluviatilis var. mexicana Gee, 193 le, p. 43; 1932c, p. 30. — Rioja, 1940a, 



p. 178.— Martinez, 1940, p. 191. 



Material. — Extremely numerous specimens and slide material; 

 EUROPE: Sweden, Finland, Netherlands, Belgium, France, Switzer- 

 land, Germany, Austria, Hungary, Czechoslovakia, Poland, Yugo- 

 slavia, Italy, U.S.S.R.; NORTH AMERICA: U.S.A., Mexico; 

 ASIA: U.S.S.R., China, India, Japan; AUSTRALIA: New South 

 Wales, Queensland; AFRICA: slides of syntype of E.f. capensis. 



Description, — Matiu-e sponge often forming bulbous and corru- 

 gated growths on timber and aquatic plants, rarely flat crusts; surface 

 typically uneven and lobose, oscula numerous and relatively large, 

 dermal membrane weU developed. Skeleton consisting of polyspicular 

 longitudinal fibers, coated together in well defined sheaths of spongin; 

 and of a variable number of secondary transverse fibers. Consistency 

 of live sponge firm but nevertheless fragile, skeleton of dry sponge 

 extremely brittle. 



Megascleres slightly curved, rarely straight amphioxea, ranging 

 from fusiform to almost cylindrical, typically entirely smooth; length 

 range 210-400 n, width range 6-19 m- 



Microscleres absent. 



Gemmoscleres typically birotulates of one class, with a slender 

 and smooth shaft, and terminally with rotules of equal diameter and 

 distinctly flat shape, irregidarly and not too deeply incised; malforma- 

 tions frequent in adverse environments, resulting in the projection of 

 the axis through the rotules, or a number of irregular spines on the 

 shafts; length of shaft typically 26-30 m, diameter of rotules ranging 

 18-21 n; marginal teeth on rotules usuaUy not less than 20. 



Gemmules rather abundant, scattered throughout skeletal mesh- 

 work, spherical, ranging in diameter 350-450 /x; pneumatic layer 

 weU developed but comparatively shallow, consisting of minute 

 spherical air spaces; gemmoscleres embedded in this coat in one 

 layer and strictly radially, resting with one rotule on inner gemmular 



