NO. 1205. SYNOPSIS OF THE NAIADES— SIMPSON. 763 



tPLEUROBEMA ARGENTEA Lea. 



*Unio argentens Lea, Pr. Am. Phil. Soc, II, 1841, p. 82; *Tr. Am. Phil. Soc. VIII, 

 1843, p. 242, pi. XXV, fig. 57 ; * Obs. , III, 1842, p. 80, pi. xx v, fig. 57.— " Conrad, 

 Pr. Ac.N. Sci. Phila., VI, 1853, p. 245.— ^Chenu, 111. Conch., 1858, pi. xxxiii, 

 figs. 2, 2a, 2&.— H. and A. Adams, Gen. Eec. Moll., II, 1857, p. 495.—* Kuster, 

 Conch. Cab. Unio, 1861, p. 188, pi. lix, fig. 4 ; 1861, p. 225, pi. lxxvi, fig. 3.— 



* SowERBY, Conch. Icon., XVI, 1868, pi. xxxvii, fig. 204.—* B. H. Wright, 

 Check List, 1888.— *Pjetel, Conch. Sam., Ill, 1890, p. 145. 



*Margaron {Unio) argentens Lea, Syn., 1852, p. 26; 1870, p. 40. 



Upper Tennessee Eiver drainage. 



tPLEUROBEMA ARGENTEA var. PANNOSA Simpson. 



* Pleurobema argentea pannosa Simpson, Pr. Ac. N. Sci. Phila., 1900, p. 82. 



A solid, somewhat inflated, roughened form from Hot Springs, Arkan- 

 sas, may be designated as above. Probably a valid species. 



tPLEUROBEMA CONASAUG^NSIS Lea. 



*Unio conasaugwnsis Lea, Pr. Ac. N. Sci. Phila., II, 1872, p. 155.— *J1. Ac.N. Sci. 

 Phila., VIII, 1874, p. 33, pi. x, fig. 30; *0b8., XIII, 1874, p. 37, pi. x, fig. 30.— 

 '^B. H. WRiiJHT, Check List, 1888. 



Upper Tennessee Eiver drainage. 



tPLEUROBEMA BREVIS Lea. 



*Unio &rems Lea, Pr. Ac.N. Sci. Phila., II, 1872, p. 157; *J1. Ac. N. Sci. Phila., 

 VIII, 1874, p. 35, pi. xii, fig. 32; *0b8., XIII, 1874, p. 39, pi. xii, fig. 32.— 

 *B. H. Wright, Check List, 1888. 



Tennessee Eiver system ; Hardy, Arkansas. 



tPLEUROBEMA BREVIS var. SUBILLIPTICA Simpson. 



*Pleurohema irevis suUlliptica Simpson, Pr. Ac. N. Sci. Phila., 1900, p. 80. 



A solid, inflated form from Hardy, Arkansas, may bear this name. 

 It is probably a distinct species. 



tPLEUROBEMA PLANIOR Lea. 



""Unio planior Lea, Pr. Ac. N. Sci. Phila., XII, 1868, p. 145; *J1. Ac. N. Sci. 

 Phila.,VI, 1869, p. 316, pi. l, fig. 129; *Obs., XII, 1869, p. 76, pi. l, fig. 129.— 



* B. H. Wright, Check List, 1888. 

 *Margaron (Unio) planior LiTSa, Syn., 1870, p. 35. 



Upper Tennessee Eiver drainage. 



tPLEUROBEMA ESTABROOKIANA Lea. 



"" Unio estairookianus 'Lea, Pr. Am. Phil. Soc, IV, 1845, p. 164; *Tr. Am. Phil. 

 Soc, X, 1853, p. 77, pi. vi, fig. 17; * Obs., IV, 1848, p. 51, pi. vi, fig. 77.— 

 *CoNRAD, Pr. Ac. N. Sci. Phila., VI, 1853, p. 248.— *H. and A. Adams, Gen. 

 Eec. Moll., II, 1857, p. 495.— *B. H. Wright, Check List, 1888. 



*Margaron ( Unio) estahrooManus Lea, Syn., 1852, p. 24; 1870, p. 35. 



*Unio estabroManiis Pjetej., Conch. Sam., Ill, 1890, p. 152. 



