﻿26 TRUNCIM.A 



Ohio River drainage and southern Michigan. 



Type locality, Ohio River, Cincinnati, O. 

 Unio rangianus Lea, Trans. Am. Phil. Soc, VI, 1839, p. 95, 



pi. XVIII, fig. 56; Obs., II, 1838, p. 95, pi. xviii, fig. 56. — 



Hanlky, Biv. Shells, 1843, p. 187, pi. xxi, fig. 48. — Chenu., 



111. Conch., 1858, pi. XXIV, figs. 5, 5a, 5^. — Kuster, Conch. 



Cab. Unio, 1861, p. 257, pi. lxxxvii, fig. i ; lxxxix, fig. i. 



— Reeve, Conch. Icon., XVI, 1864, pi. xiv, fig. 54. 

 Margarita (Unio) rangianus Lea, Syn., 1838, p. 18. 

 Margaron (Unio) rangianiis Lea, Syn., 1852, p. 26; 1870, p. 



40. 

 Trimcilla pcrplcxa var. rangiana Simpson, Syn., 1900, p. 523. 

 Truncilla rangiana Ortmann, Ann. Car. Mus., VIII, 1912, p. 



358, fig. 2^. 

 Unio gubernaculiim Reeve, Conch. Icon., XVI, 1865, pi. xxviii, 



fig. 146. 



It is claimed by some excellent authorities that this form is 

 specifically distinct from perplexa, but I have seen so much 

 connecting material that I cannot satisfactorily separate the 

 two. 



Var. cincinnatiensis (Lea). 



Shell having numerous small, somewhat sharp knobs on the 

 radial ridge with sometimes a few on the posterior ridge and 

 even an intermediate row in the furrow between the two; mar- 

 supial swelling of the female more inflated than in the type. 



Type locality, Ohio River, Cincinnati, O. 

 Unio cincinnaiicnsis Lea, Proc. Am. Phil. Soc, I, 1840, p. 285; 



Tr. Am. Phil. Soc, VIII, 1842, p. 194, pi. viii, fig. 4; Obs. 



Ill, 1842, p. 32, pi. viii, fig. 4.— Chenu, 111. Conch., 1858, pi. 



XXX, figs. 3, 3a, 3&. 

 Margaron (Unio) cvncinnatiemis Le.\. Syn.. 1852, p. 22; 1870, 



P-33- 

 Truncilla perplexa var. cincinnatiensis Simpson, Syn., 1900, 



p. 523. 

 Unio phillipsii Reeve, Conch. Icon., XVI, 1864, pi. iv, fig. 15. 



