A new name for Styphlodora compactum Dawes, 1941, a criticism of the proposed new genus Paurophyllum Byrd, Parker & Reiber, 1940, and a revised key for the separation of species of the genus Styphlodora Looss, 1899

1. The homonym Styphlodora compactum Dawes, 1941, has been renamed S. compressa. 2. Several suggestions have been made regarding the invalidity of proposed species of the genus Styphlodora. S. compactum Byrd, Parker & Reiber, 1940, should be regarded as a synonym of S. bascaniensis Goldberger, 1911, S. natricis as a synonym of S. magna Byrd & Denton, 1938, S. agkistrodontis as a synonym of S. floridanis Byrd, Parker & Reiber, 1940, S. lachesidis as a synonym of S. horridum (Leidy, 1850). 3. A suggestion has been made to relegate the proposed genus Paurophyllum Byrd, Parker & Reiber, 1940, to synonymity with the genus Styphlodora Looss, 1899. The proposed new species Paurophyllum simplexus and P. megametricus Byrd, Parker & Reiber, 1940, are identical and should be known as Styphlodora simplexa (Byrd, Parker & Reiber, 1940a) n.comb. S. aspina Byrd, Parker & Reiber, 1940, is a synonym of this species. 4. A revised key to the sixteen apparently valid species of the genus Styphlodora has been constructed. S. floridanis and S. simplexa have been found places in it provisionally, though it is suggested that further study of the trematode parasites of the kidney of Agkistrodon piscivorus might result in the merging of these species into a single species, namely, Styphlodora simplexa (Byrd, Parker & Reiber, 1940).