NO. 1205. STXOPSIS OF THE NAIADES— SIMPSOX. 767 



tQUADRULA PLICATA Say. 



" Unio ])licata Say,' Nich. Encyc.,!!, 1816, pi. iii, fig. 1. 



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

 *if2/a_pZicata Eaton, Zool. Text-Book, 1826, p. 219. 



* Quadrula plicaia Baker, Moll. Chicago, Pt. 1, 1898, pi. xxv, fig. 1. 



*TJnio pUcatus Hildreth (?), Am. Jl. Sci., XI V, 1828, p. 280."— 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.— 

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

 21. — *Catlow and Eeeve, Conch. Norn., 1845, p. 63. — *Kuster, Conch. 

 Cab. Unio, 1856, p. 137, pi. xi., fig. 3. — *H. and A.Adams, Gen. Eec, Moll., 

 11,1857, p. 498.— 'Reeve, Conch. Icon., XVI, 1864, pi. ii, fig. 5.— *B. H. 

 Wright, Check List, 1888.— *P^tel, Conch. Sam., Ill, 1890, p. 163. 



* Margarita (Unio) 2}licatus'L^A, Syn., 1836, p. 12; 1838, p. 14. 

 *Margaron ( Unio) pUcatus 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.^ — * Desha yes, An. sans 



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

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



* Unio rariplicata Deshayes, Enc. M6th., II, 1830, p. 578; *Au. sans Vert., 2d ed., 



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

 ^Unio giganteus Lea, Obs., II, 1838, p. 35.-* 

 ""Unio lieros Kuster, Conch. Cab. Unio, 1856, p. 136, pi. xl, figs. 1, 2. 



fUNIO PLICATA van HIPPOP^A Lea. 



*Z7mo liippopwm Lea," Pr. Am. Phil. Soc, IV, 1845, p. 163; * Tr. Am. Phil. Soc, 



X, 1848, p. 67, pi. I, 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) Idppopccus Lea, Syn., 1852, p. 21; 1870, p. 31. 



* Unio hippopoeus Pjetel, Conch. Sam., Ill, 1890, p. 155. 



Upper Mississippi drainage area south to the Tennessee and Arkansas 

 rivers ; Eed River of the I^orth ; Saskatchewan River ; Lake Winni- 

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

 Erie. 



tQUADRULA PERPLICATA Conrad. 



*Unio perplicatm Conrad, Pr. Ac. N. Sci. Phila., I, 1841, p. 19; *J1. Ac.N. Sci. 

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



^ 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. 



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

 left out by the editor. 



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

 Say's j;Kc«ia. 



■•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. 



