664 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxii. 



- tr«/o perienms Lka, Pr. Ac. N. Sci. Pbila., VII, 1863, p. 193; " Jl. Ac. N. Sci. 



Phila., VI, 1866, p. 8, pi. ii, fig. 4; *Obs., XI, 1867, p. 12, pi. ii, fig. 4.— *B. 



H. Wright, Check List, 1888. 

 ^Margaron {Unio) ])erienuis Lka, Syn,, 1870, i>. 62. 



Streams draining into the Atlantic from New York south to North 

 Carolina; Alonroe County, Michigan"? 



i SYMPHYNOTA DECORATA Lea. 



" Unio decoratus Lea, Tr. Am. Phil. Soc, X, 1852, p. 257, pi. xiii, fig. 6 ; * Obs., V, 



1852, p. 13, pi. xiii, fig. 6.—* Conrad, Pr. Ac. N. Sci. Phila., VI, 1853, p. 248.— 



*H. and A. Adams, Gen. Rec. Moll., 11,18.57, p. 498. — "Sowerby, Conch. Icon., 



. XVI, 1868, pi. xci, fig. 496.— *B, H. Wright, Check List, 1888.— *P/ETEl, 



Conch. Sam., Ill, 1890, p. 150. 



'' Margaron {Unio) decoratus Lea, Syn., 1852, p. 19; 1870, p. 29. 



*t Unio insolidus Lea, Pr. Ac. N. Sci. Phila., II, 1872, p. 159; *J1. Ac. N. Sci. 

 Phila., VIII, 1874, p. 40, pi. xiii, fig. 37; *Obs., XIII, 1874, p. 44, pi. xiii, 

 fig. 37.— *B. H. Wright, Check List, 1888. 



Virginia to South Carolina. 



t SYMPHYNOTA NEGLECTA Lea. 



Unio veglectns Lea, Desc. 12 Uniones, 1843; * Tr. Am. Phil. Soc, IX, 1846, p. 280, 



pi. xi.ii, fig. 10 ; * Obs., IV, 1848, p. 88, pi . xLii, fig. 10.—* Conrad, Pr. Ac. N. 



Sci. Phila., VI, 18.53, p. 252.— *H. and A. Adams, Gen. Eec. Moll., II, 1857, p. 



493.— ^^KuSTER, Conch. Cab. Unio, 1861, p. 225, pi. lxxvi, fig. 4.— *B. H. 



Wright, Check List, 1888.— * P.etel, Couch. Sam., Ill, 1890, p. 160. 

 " Margaron ( Unio) neglectns Lea, Syn., 1852, p. 33; 1870, p. 54. 



Northern Alabama. 



t SYMPHYNOTA QUADRATA Lea. 



■■ Margaritana quadrata Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 41 ; * Jl. Ac. N. Sci. 



Phila., II, 1862, p. 210, pi. xxxji, fig. 279; *Obs., IX, 1863, p. 32, pi. xxxii, 



fig. 279.— *B. H. Wright, Check List, 1888.— *PiETEL, Couch. Sam., Ill, 



1890, p. 173. 

 " Margaron {Margaritana) quadrata Lea, Syn., 1870, p. 68. 

 " Margaritana {Alasmodonta) quadrata Ci.ESSiN, Conch. Cab. Ano., 1876, p. 273, 



pi. Lxxxiii, figs. 5, 6. 



Eastern Tennessee. 



Subgenus LASMIGONA Rafinesque, 1831. 

 (Type, Alasynidonta costata Rafinesque,)' 



Shell subrhomboid, compressed, corrugated behind; beaks low, their 

 sculpture consisting of several coarse ridges which generally fall into 

 two slight loops, and often with radiating ridges in front and behind; 

 epidermis shining; laterals partly developed, consisting of blurred ridges 

 which slope diagonally downward and backward on the hinge plate; 

 cavities of the beaks shallow; dorsal scars faint, irregular. 



' The description of Alasmidonta costata of Rafiuesqne so clearly covers the species 

 described three years later as Alasmodonta rugosa by Barnes that the former name 

 must be used. 



