518 PBOCEEDINGS OF THE NATIONAL MUSEUM. vol.xxii. 



* Unio inierruptiis Conkad, New F. W. Shells, 1834, p. 69.—* Say, Am. Conch., VI, 



1834.— *CoNi{AD, Monog.,X, 1838, p. 88, pi. xlviii; *Pr. Ac. N. Sci., Phila., 

 VI, 1853, p. 250.— *KusTER, Conch. Cab. Unio, 1861, p. 182, pi. lvii, fig. 3; 

 pi. LX, fig. 2.—* Eeeve, Conch. Icon., XVI, 1864, pi. xiv, fig. 56. 

 ^Truncilla interrupta Agassiz, Arch, fiir Natnrg., 1, 1852, j). 44. 



Tennessee drainage. 



fTRUNCILLA PENITA Conrad. 



* Unio penitus Conrad, New F. W. Shells, 1834, pp. 33, 70, pi. v, fig. 1. — * Fehussac, 



Giier. Mag., 1835, p. 29.— *Moller, Syn. Nov. Gen., 1836, p. 203.— *Hanley, 

 Test. Moll., 1842, p. 183; * Biv. Shells, 1843, p. 183.— "Catlow and Reeve, 

 Conch. Norn., 1845, p. 62. — *Chenu, Bib. Conch., lstser.,111, 1845, p. 18, pl.iii, 

 fig. 9.—* Conrad, Pr. Ac. N. Sci., Phila., VI, 1853, p. 254.— « H. and A. Adams, 

 Gen.Rec. Moll. , II, 1857, p. 495.— * Reeve, Conch. Icon., XVI, 1864, pi. xiv, 

 fig. 55.— *PiETEL, Conch. Sam., Ill, 1890, p. 162. 



"Margm-ita ( Unio) penitus Lea, Syn., 1836, p. 19; 1838, p. 16. 



*Margaron ( Unio) penitus Lea, Syn., 1852, p. 24; 1870, p. 36. 



* Uniocompactns'L^A, Proc. Ac. N. Sci. Phila., Ill, 1859, p. 154 ; 'Jl. Ac. N. Sci. Phila., 



IV, 1859, p.218, pi. XXVIII, fig. 98 ; * Obs.' VII, 1859, p. 36, pi. xxviii, fig. 98. 

 '*Margaron ( Unio) compactus Lea, Syn., 1870, p. 36. 



Alabama and Tombigbee river drainage. 



tTRUNCILLA MODICELLA Lea. 



* Unio modieellus Lea, Pr. Ac. Phila., Ill, 1859, p. 171; * Jl. Ac. N. Sci. Phila., IV, 



1860, p. 347, pi. LVii, fig. 172; ^Obs., VIII, 1860, p. 29, pi. Lvii, fig.172.— ^B.H. 

 Wright, Check List, 1888. 

 *Margaron (Unio) modieellus '^ Lea, Syn., 1870, p. 41. 



Connasaugua and Chattanooga rivers, northwest Georgia. 



The following species^ are unflgured and indeterminate: 



Truncilla ( Unio) perplexus Ratinesque. 



Truncilla granulatns Rafinesque. 



Unio (Truncilla) metaplata Rafinesque. 



tTRUNCILLA LENIOR Lea. 



* Unio lenis Lea, Pr. Am. Phil. Soc, 1, 1840, p. 286.» 



* Unio lenior Lea., Tr. Am. Phil. Soc, VIII, 1843, p. 204, pi. xii, fig. 18; *Obs., Ill, 



1842, p. 42, pi. XII, fig. 18.— *C0NRAi), Pr. Acad. N. Sci. Phila., VI, 1853, p.251.— 

 *CiiENU, 111. Conch., 1858, pi. xxvii, figs. 4, 4a, 4?*. — *H. and A. Adams, Gen. 

 Rec. Mol].,II, 1857, p. 492.— *Reeve, Conch. Icon., XVI, 1864, pi. xvii, fig. 

 75.— *P.ETEL, Conch. Sam., Ill, 1890, p. 157. 

 ""Margaron (Unio) lenior Lea, Syn., 1852, p. 39; 1870, p. 62. 



Stone Elver, Tennessee; near Woodville, Alabama. 



'Four specimens of this species are in the U. S. National Museum collection, from 

 the Connasauga River, Georgia, three of which are males, with a form something 

 like that of T. penita; the fourth is a young female, which distinctly shows a 

 radiately ridged post-basal swelling. 



"These are m continuation of Mouography, 1831, p. 4. 



^Lea changed his name lenis to lenior, probably because Conrad had previously 

 used the former for a species of U^iio, which is no doubt a young ventricosus. 



