REVISION OF FRESHWATER SPONGES OP SPONGILLIDAE 135 



transitional skeletal constructions leading from the mode found in 

 Trochospongilla to that of Uruguaya. Species of the former genus are 

 now also known to possess firm, though never stony, skeletal arrange- 

 ments and it could well be possible that intermediate links will be 

 found. Should this happen, the relegation of the weU-known and well- 

 defined cosmopoHtan genus of Vejdovsky to a synon3mi of the locahzed 

 name of Carter's genus will be inevitable, or legaHstic steps will have 

 to be taken to declare Uruguaya an inappropriate genus. It certainly 

 would be a choice of evils. 



Six of the eight presently known species of Trochospongilla are dealt 

 mth below in detail. The remaining two, T. gregaria (Bowerbank) and 

 T. minuta (Potts), are not represented in the material available for this 

 study and have to be disregarded, 



Trochospongilla horrida Weltner, 1893 



Plate 12, figures I, 2 



Spongilla erinaceus Lieberkiilin, 1856, p. 496. 



Trochospongilla erinaceus Vejdovsky, 1883b, p. 31; lSS3a, p. 332; in Potts, 1887, 



p. 176.— Dybowsky, 1882, p. 3; 1886, p. 295.— Wierzejski, 1885, p. 1. 

 Trochospongilla horrida Weltner, 1893, p. 12; 1895, p. 120.— Girod, 1899, p. 



109.— Topsent, 1914, p. 538.— Smith, 1921, p. 17.— Arndt, 1923, p. 75; 



1926, p. 344; 1928a, p. 78.— Rezvoj, 1926b, p. 64; 1928, p. 226.— Gee, 1926a, 



p. 182; 1931a, p. 501; 1931e, p. 40; 1932b, p. 4; 1932c, p. 42.— Schroder, 



1926, p. 249; 193Sa, p. 295; 1938b, p. 126.— Grimailowskaja, 1928, p. 215.— 



Old, 1932c, p. 239; 1936b, p. 11.— Eshleman, 1950, p. 44.— Wurtz, 1950, 



p. 6.— Simon, 1951, p. 133; 1952, p. 80; 1953, p. 207.— Penney, 1954, p. 156; 



1960, p. 55. 

 Meyenia erinaceus Carter, 1881a, p. 90. — Potts, 1887, p. 210. 

 Trochospongilla horrida var. ningpoensis Gee, 1926a, p. 182; 1926c, p. 110; 1927a, 



p. 1; 1927b, p. 63; 1928b, p. 225; 1930e, p. 27; 1930d, p. 369; 1931e, p. 44; 



1932b, p. 6; 1932c, p. 42; 1932d, p. 54. 

 Trochospongilla sol Annandale, 1918a, p. 205. — Gee and Wu, 1925b, p. 342.— 



Gee, 1926a, p. 183; 1926c, p. 110; 1926b, p. 237; 1927b, p. 61; 1927a, p. 1; 



1928b, p. 225. 

 Trochospongilla horrida var. sol Gee, 1931e, p. 49; 1932b, p. 9; 1932d, p. 53; 



1932c, p. 42.— Penney, 1960, p. 56. 

 Trochospongilla polysclera Rezvoj, 1926a, p. 109. 



Material. — Very numerous specimens and sHdes; EUROPE: 

 Germany, Poland, Czechoslovakia, U.S.S.R.; NORTH AMERICA: 

 Illinois, Ohio, South Carolina; ASIA: U.S.S.R., China; two sHdes 

 of type of T. polysclera (N. Gist Gee). 



Description. — Mature sponge forming flat crusts of moderate 

 dunensions; surface sKghtly uneven and hispid, oscula conspicuous 

 but small. Skeleton consisting of an irregular network of spicule 

 fibers, joined together by a varying amount of spongm. Consistency 

 ranging from fragile to moderately hard. 



