NO. 1205. SYNOPSIS OF THE NJIADES— SIMPSON. 787 



tQUADRULA CERINA Conrad. 



*Unio cerinus Conrad, Mouog., XI, 1838, p. 95, pi. Lii; *Pr. Ac. N. Sci. Phila., 

 VI, 1853, p. 246.— * SowERBY, Conch. Icon., XVI, 1868, pi. lxxxvii, fig. 468.— 

 " B. H. Wright, Check List, 1888.— "* P.etel, Couch. Sam., Ill, 1890, p. 147. 



Louisiana; eastern Texas ; Mississippi; Alabama; north to Arkansas. 



tQUADRULA HEBETATA Conrad. 



* Unio hebetatus Conrad, * Jl. Ac. N. Sci. Phila., II, 1854, p. 296, pi. xxvi, fig. 5.— 



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

 *Margaron ( Unio) habetatus Lea, Syn., 1870, p. 38. 



Missouri; Tuscaloosa Eiver, Alabama. 



tQUADRULA RUBIDA Lea. 



*Unio rtiUdus Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 40; *J1. Ac. N. Sci. Phila., 

 V, 1862, p. 95, pi. XIV, fig. 244; * Obs., VIII, 1862, p. 99, pi. xiv, fig. 244.— 



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

 *Margaron ( Unio) rnhidiis Lea, Syn., 1870, p. 35. 



t * Unio negatus Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 59 ; * Jl. Ac. N. Sci. Phila., 

 V, 1862, p. 76, pi. IX, fig. 225; Obs., VIII, 1862, p. 80, pl.ix, fig. 225.— *Sow- 

 ERBY, Conch. Icon., XVI, 1866, pi. xxxii, fig. 165.—* B. H. Wright, Check 

 List, 1888.— *P,etel, Conch. Sam., Ill, 1890, p. 160. 



* Margaron ( Unio) negatus Lea, Syn., 1870, p. 35. 



Streams flowing- into the Gulf of Mexico from Alabama to Louisiana. 

 The shell reported under the name Unio negatus, from Kansas, is prob- 

 ably a somewhat sulcate ruMginosus. 



tQUADRULA CHUNII Lea. 



Unio chunii Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 392; * Jl. Ac. N. Sci. Phila., 

 V, 1862, p. 196, pi. xxvii,p. 265; *Obs., IX, 1863, p. 18, pi. xxvii, fig. 2'65.— 

 ' B. H. Wright, Check List, 1888.—* P.etel, III, 1890, p. 148. 



^Margaron (Unio) chunii Lea, Syn., 1870, p. 38. ' 



Mississippi; west to central Texas north to Arkansas. 



tQUADRULA RIDDELLII Lea. 



* Unio riddelUi Lea, Pr. Ac. N. Sci. Phila., V, 1861, p. 392 ; * Jl. Ac. N. Sci. Phila., 



V, 1862, p. 198, pi. xxvii, fig. 267; " Obs., IX, 1863, p. 20, pi. xxvii, fig. 267.— 

 *SowERBY, Conch. Icon., XVI, 1868, pi. lxxxiii, fig, 442.— *B. H.Wright, 

 Check List, 1888.—* P^etel, Conch. Sam., Ill, 1890, p. 165. 

 *Margaron ( Unio) riddellii Lea, Syn., 1870, p. 38. 



Dallas, Texas. 



t QUADRULA FRIERSONI B. H. Wright. 

 "" Unio friersoni B. H. Wright, Nautilus, IX, 1896, p. 134, pi. iii. 

 Louisiana; eastern Texas. 



tQUADRULA TRIGONA Lea. 



* Unio trigonus, Lea, Tr. Am. Phil. Soc, IV, 1831, p. 110, pi. xvi, fig. 40; * Obs., I, 



1834, p. 120, pi. XVI, fig. 40.— * Hanley, Test. Moll., 1842, p. 185 ; * Biv. Shells, 

 1843, p. 185, pi. XXI, fig. 6.—* Catlow and Eeeve, Conch. Nom., 1845, p. 64. — 



* Conrad, Pr. Ac. N. Sci. Phila., VI, 1853, p. 258.—* H. and A. Adams, Gen. Eec. 

 Moll., II, 1857, p. 496.—* Chenu, 111. Couch., 1858, pi. xvi, figs. 7, la, lb.~ 



