NO. 1205. SYNOPSIS OF THE NAIADES SIMPSON. 767 



tQUADRULA PLICATA Say. 



* Unio plicata SAY,' Nich. Encyc., II, 1816, pi. in, fig. 1. 



* Unio (Theliderma) plicata SWAINSON, Tr. on Mai., 1840, p. 271, fig. 54e. 

 *Mya plicata EATON, Zool. Text-Book, 1826, p. 219. 



* Quadrula plicata BAKER, Moll. Chicago, Pt. 1, 1898, pi. xxv, fig. 1. 



*Unio plicahis HILDRETH (?), Am. Jl. Sci., XIV, 1828, p. 280. 2 SHORT and 

 EATON, Transylvania Jl., 1831, p. 74. * CONRAD, New F. W. Shells, 1834, 

 p. 71. * SAY, Am. Conch., VI, 1834. *FERUSSAC, Guer. Mag., 1835, p. 27. 



* HANLE Y, Test. Moll, 1842, p. 175 ; * Biv. Shells, 1843, p. 175, pi. xxi, fig. 

 21. *CATLOW and REEVE, Conch. Nom., 1845, p. 63. *KLTSTER, Conch. 

 Cab. Unio, 1856, p. 137, pi. XL, fig. 3. * H. and A.ADAMS, Gen. Rec. Moll., 

 11,1857, p. 498. * REEVE, Conch. Icon., XVI, 1864, pi. n, fig. 5. * B. H. 

 WRIGHT, Check List, 1888. *P.ETEL, Conch. Sam., Ill, 1890, p. 163. 



* Margarita ( Unio) plicatus LEA, Syn., 1836, p. 12; 1838, p. 14. 

 *Margaron ( Unio) plicatus LEA, Syn., 1852, p. 20; 1870, p. 30. 

 *Plectomerus plicatus CONRAD, Pr. Ac. N. Sci. Phila., VI, 1853, p. 261. 



* Unio peruviana LAMARCK, An. sans Vert., VI, 1819, p. 71. 3 * DESHAYES, An. sans 



Vert.,2d ed., VI, 1835, p. 533; 3d ed., II, 1839, p. 667. 

 *Unio crassus BAKNES, Am. Jl. Sci., VI, 1823, p. 118. 



* Unio rariplicata DESHAYES, Enc. Me"th., II, 1830, p. 578; *An. sans Vert., 2ded., 



VI, 1835, p. 533; 3d ed., II, 1839, p. 667. 

 *Unio glganteus LEA, Obs., II, 1838, p. 35. 4 

 *Unio Jieros KUSTER, Conch. Cab. Unio, 1856, p. 136, pi. XL, figs. 1, 2. 



tUNIO PLICATA var. HIPPOPjEA Lea. 



*Unio hippop(eu8~LKA, Pr. Am. Phil. Soc., IV, 1845, p. 163; *Tr. Am. Phil. Soc., 

 X, 1848, p. 67, pi. l, fig. 1; *Obs., IV, 1848, p. 41, pi. i, fig. 1. *H. and A. 

 ADAMS, Gen. Rec. Moll., II, 1857, p. 497. * KUSTER, Conch. Cab., 1861, p. 

 251, pi. LXXXIV, fig. 3.* REEVE, Conch. Icon., XVI, 1864, pi. xi, fig. 40. 



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



*Margaron ( Unio) Idppopwns LEA, Syn., 1852, p. 21 ; 1870, p. 31. 



* Unio hippopceus P.ETEL, Conch. Sam., Ill, 1890, p. 155. 



Upper Mississippi drainage area south to the Tennessee and Arkansas 

 rivers; lied Biver of the North; Saskatchewan River; Lake Winni- 

 peg; western Michigan. The variety in eastern Michigan and Lake 

 Erie. 



tQUADRULA PERPLICATA Conrad. 



*Unio perplicatus CONRAD, Pr. Ac. N. Sci. Phila., I, 1841, p. 19; *J1. Ac. N. Sci. 

 Phila., VIII, 1842, p. 178; "I, 1850, p. 276, pi. xxxvm, fig. 2. *H. and A. 



1 Say says : " It was found by Mr. Lesueur in Lake Erie, and was communicated by 

 him under the above name." As there is no evidence that Lesueur described the 

 species, and as Say was the one to first properly characterize it, I believe that he 

 must be credited with it. 



-Referred to figure 5, but this with a number of other figures in this paper were 

 left out by the editor. 



3 Lea, who examined Lamarck's types and collection, states that this is the same as 

 Say's plicata. 



Dr. Lea does not describe this, but only states that it is in Dr. Mitchell's collec- 

 tion. Probably it has never been described. 



"Apparently a stunted variety of Quadrula plicata. Dr. Lea's specimens show a 

 great diversity of characters. 



