758 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxii. 



* Margarita ( Unio) rubellus Lea, Syn., 1836, p. 33; 1838, p. 28. 

 *Margaron ( Unio) rubellus Lea, Syn., 1852, p. 34; 1870, p. 55. 



t * Unio rudis Conrad, i Monog., No. 9, 1837, p. 76, pi. xliii, fig. 1. — *B. H. Wright, 

 Check List, 1888. 



t* Unio pulvinulus Lea, Pr. Am. Phil. Soc, IV, 1845, p. 164; *^Tr. Am. Phil. Soc, 

 X, 1848, p. 81, pl.vni, fig. 24; * Obs., IV, 1848, p. 55, pi. viii, fig. 24.—* Conrad, 

 Pr. Ac. N. Sci. Phila., VI, 1853, p. 255.— *n. and A. Adams, Gen. Eec. Moll., 



II, 1857, p. 495.— * B. H. Wright, Check List, 1888.—* P^tel, Conch. Sam., 



III, 1890, p. 164. 



*Margaron (Unio) pulvinulus Lea, Syn., 1852, p. 26; 1870, p. 41. 



Black Warrior and Oahawba rivers, Alabama. 



t PLEUROBEMA FURVA Conrad.^ 



* Unio furvus Conrad, New F. W. Shells, 1834, p. 39, pi. vi, fig. 3, page 69.— 



*Ferussac, Guer. Mag., 1835, p. 29.—* Moller, Syn. Nov. Gen., 1836, p. 205.— 

 *Chenu, Bib. Conch., 1st ser.. Ill, 1845, p. 20, pi. ii, fig. 4. — * Conrad, Pr. 

 Ac. N. Sci. Phila., VI, 1853, p. 250.—* B. H. Wright, Check List, 1888. 



Black Warrior River, Alabama. 



t PLEUROBEMA AVELLANA Simpson. 



*Pleurohema avellana Simpson, Pr. Ac. N. Sci. Phila., 1900, p. 81, pi. ii, figs. 6, 7. 

 Cahawba Eiver, Alabama. 



t PLEUROBEMA NUX Lea. 



* Unio mix Lea, Tr. Am. Phil. Soc, X, 1852, p. 283, pi. xxiv, fig. 43 ; * Obs. V, 1852, 



p. 39, pi. XXIV, fig. 43.—* H. and A. Adams, Gen. Eec. Moll,, II, 1857, p. 494.— 



*B. H. Wright, Check List, 1888.—* P^etel, Conch. Sam., Ill, 1890,p. 161. 

 *Margaron ( Unio) nux Lea, Syn., 1852, p. 31 ; 1870, p. 49. 

 t Unio cinnamomicus Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 39; * Jl. Ac. N. Sci. 



Phila., V, 1862, p. 100, pi. xvi, fig. 248; * Obs., VIII, 1862, p. 104, pi. xvi, tig. 



248.—* SOWERBY, Conch. Icon., XVI, 1868, pi. Lxxxiii, fig. 438.—* B. H. 



Wright, Check List, 1888. 



* Margaron ( Unio) cinnamomicus Lea, Syn., 1870, p. 49. 



Alabama River system. 



t PLEUROBEMA PINKSTONI S.H.Wright, 



* Unio pinTcstoni S. H. Wright, Nautilus, X, 1897, p. 136. 



* Pleurobema pinTcsioni Simpson. Pr. Ac. N. Sci. Phila., 1900, p. 81, pi. i, fig. 8. 



Alabama River system. 



1 Conrad says that U. ravenelianus of Lea is the same as his U. rudus, which, accord- 

 ing to Eavenel, is found in the French Broad Eiver, though Conrad obtained his 

 species in the Black Warrior. The species of Conrad is, however, quite distinct from 

 that of Lea, the two never occurring in the same drainage system. 



2 1 have seen what I believe are specimens of this species from the collections of 

 the Hon. T. H. Aldrich and Mr. Bryant Walker, taken from the Black Warrior 

 River, Alabama, but I think it not improbable that it may run into P. rubella. 



