590 PIWCEEDINGS OF THE NATIONAL MUSEUM. 



tMEDIONIDUS PARVULUS Lea. 



* Unioparvnlns Lea, Pr. Ac. N. Sci. Phila., IV, 1860, p. 307 ; * .11. Ac. N. Sci. Phila., 



VI, 1866, p. 45, pi. XVI, fig. 43; *Obs,, XL, 1867, p.49,pl.xvi, fig.43.— *B. H. 

 Wright, Check List, 1888. 

 '^Margaron {Unio) parvulus'LTS.K, Syu., 1870, p. 32. 



Coosa Eiver, Alabama; Chattauooga aud Swamp creeks, northwest 

 Georgia. 



tMEDIONIDUS PENICILLATUS Lea. 



* Unio penicillatus 1a^\, Pr. Ac. N. Sci. Phila., IX, 1857, p. 171; *J1. Ac. N. Sci. 



Phila., IV, 1859, p. 203, pi. xxiii, fig. 85; *Obs., VII, 1859, p. 21, pi. xxiii, 

 fig. 85. — * B. H. Wright, Check List, 1888. 

 ^Margaron ( Unio) penicillatus Lea, Syn., 1870, p. 32. 



Chattahoochee and Flint rivers, (xeorgia. 



tMEDIONIDUS KINGI B. H. Wright. 

 Unio kingi B. H. Wright, Nautilus, XII, 1900, p. 138. 

 Branch of Flint Eiver, Baker County, Georgia. 



tMEDIONIDUS ACUTISSIMUS Lea. 



"" Unio acutissimus Lea, Tr. Am. Phil. Soc, IV, 1831, p. 89, pi. x, fig. 18; *Obs., I, 

 1834. p. 99, pi. \, fig. 18.—* Conrad, New F.W. Shells, 1834, p.67.— * Ferussac, 

 Guev. Mag., 1835, p. 28.— * Conrad, Mouog., X, 1838, p. 86, pl.XLVii, fig. 2.— 

 *Hanley, Test. Moll., 1842, p. 177; '"Biv. Shells, 1843, p. 177, pi. xxii, fig. 35.— 

 ■*Catlow and Eeeve, Couch. Norn., 1845, p. 55.— * Conrad, Pr. Ac. N. Sci. 

 Phila., VI, 1853, p. 244.—' H. and A. Adams, Geu. h'ec. Moll., II, 1857, p. 497.— 

 *Chenu, 111. Conch., 1858, pi. viii, figs. 3, 3a, 36.— *Sowehby, Conch. Icon., 

 XVI, 1866, pi. xxxvi, fig. 189.— *B. H. Wright, Check List, 1888.— "P^tel, 

 Couch. Sam., III. J890, p. 143. 



'^Margarita ( Unio) acutissimus Lea, Syn., 1836, p. 14; 1838, p. 14. 



""Margaron ( Unio) acutissimus Lea, Syn., 1852, p. 21; 1870, p. 32. 



*J7wio semiplicatus Kuster, Conch. Cab. Unio, 1862, p. 279, pi. xciv, fig. 4.>— 

 *P^tel, Conch. Sam., Ill, 1890, p. 167. 



* Unio rubellinus Lea, Pr. Ac. N. Sci. Phila., IX, 18.57, p. 32 ; ■ Jl. Ac. N. Sci. Phila., 



IV, 1858, p. 70, pi. XIII, fig. 51; 'Obs., VI, 1858, p. 70, pi. xiii, fig. 51.— 

 » SowERBY, Couch. Icon., XVI, 1868, pi. xc, fig. 490.—* B. H. Wright, Check 

 List, 1888.— '^ P.etel, Conch. Sam., Ill, 1890, p. 166. 

 *Margaron ( Unio) rubellinus Lea, Syn., 1870, p. 32. 



Alabama Eiver system. 



(Group of Medionidus ivallceri.) 



Shell rather short, inflated, with a high, posterior ridge; posterior 

 slope strongly corrugated; epidermis dark, slightly clouded; nacre red- 

 dish or greenish. 



iThere is a Unio semiplicatus of Troschel in Wiegman's Archiv. for 1841, p. 180, but 

 I do not know wliat is. Kuster credits his species to Australia, but it is evidently 

 Lea's shell, no such species being found in Australia. 



