NO. 1205. SYNOPSIS OF THE NAIADES SLVFSON. 785 



very high; beak sculpture very coarse, concentric ridges; ' disks irregu- 

 larly concentrically striate; epidermis rich, dark chestnut; hinge plate 

 rather narrow; pseudocardinals radial, stumpy; cavity of the beaks 

 only moderately deep. 



No gravid specimens have been seen, but those examined do not seem 

 to differ from others of the genus. 



fQUADRULA CHICKASAWHENSIS Lea. 



1'nio chickasawhens'w LEA, Pr. Ac. N. Sci. Phila., V, 1861, p. 39; Ml. Ac. N. Sci. 

 Phila., V, 1862, p. 101, pi., xvi, fig. 250; *0bs., VIII, 1862, p. 105, pi. xvi, 

 fig. 250.* B. IT. WRIGHT, Check List, 1888. 

 Margaron ( I'nio) chickasaivhensis LEA, Syn., 1870, p. 55. 



Mississippi and Louisiana. 



fQUADRULA SUCCISSA Lea. 



* Unio succissus LEA, Tr. Am. Phil. Soc., X, 1852, p. 275, pi. xxi, fig. 32; *Obs.,V, 



1852, p. 31, pi. xxi, fig. 32. *H. ami A. ADAMS, Gen. Rec. Moll., II, 1857, 

 p. 496. * SOWERBY, Conch. Icon., XVI, 1866, pi. xxxni, fig. 174. *B. H. 

 WRIGHT, Check List, 1888. * P.ETEL, Conch. Sam., Ill, 1890, p. 169. 

 * SIMPSON, Pr. U. S. Nat. Mus., XV, 1892, p. 29, pi. LXXI, fig. 5. 



* Margaron ( Unio) succissus LEA, Syn., 1852, p. 24 ; 1870, p. 38. 



\*Unio cacao LEA, Pr. Ac. N. Sci. Phila., Ill, 1859, p. 154; Ml. Ac. N. Sci. Phila., 

 IV, 1860, p. 344, pl.LVi, fig. 169; *Obs., VIII, 1860, p. 26, pi. LVI, fig. 169. 

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



*Margaron (Unio) cac.ao LEA, Syn., 1870, p. 54. 



West Florida ; southern Alabama. 



tQUADRULA PUMILA Lea. 



* Unio pumilus LEA, Tr. Am. Phil. Soc., VI, 1838, p. 23, pi. vn, fig. 17; *Obs., II, 



1838, p. 23, pi. vn, fig. 17.* TROSCHEL, Arch, fiir Naturg., V, 1839, Pt. 2, p. 

 234.* HANLEY, Test. Moll., 1842, p. 185; * Biv. Shells, 1843, p. 185, pi. xxin, 

 fig. 13. * CATLOW and REEVE, Conch. Norn., 1845, p. 63. * CONRAD, Pr. Ac. 

 Nat. Sci. Phila., VI, 1853, p. 255. * H. and A. ADAMS, Gen. Rec. Moll., II, 

 1857, p. 495. * CHENU, 111. Conch., 1858, pi. xix, figs. 1, la, It. * SOWERBY, 

 Conch. Icon., XVI, 1866, pi. xxxvi, fig. 198. "B. H. WRIGHT, Check List, 

 1888. * P^ETKL, Conch. Sam., Ill, 1890, p. 164. 



* Margarita ( Unio) pumilus LEA, Syn., 1836, p. 20; 1838, p. 17. 



* Margaron ( Unio) pumilus LEA, Syn., 1852, p. 24 ; 1870, p. 37. 



Black River, North Carolina. Only the type shell, a small specimen, 

 not in very good condition, has been seen by me. 



t fQUADRULA UTRICULUS Lea. 



* Unio utriculus LEA, Pr. Am. Phil. Soc., IV, 1845, p. 164; *Tr. Am. Phil. Soc., 



X, 1848, p. 69, pi. i, fig. 3; Obs., IV, 1848, p. 43, pi. i, fig. 3.* CONRAD, Pr. 

 Ac. N. Sci. Phila., VI, 1853, p. 259.* B. H. WRIGHT, Check List, 1888. 

 * Margaron ( Unio) utriculus LEA, Syn., 1870, p. 46., 



North Carolina. The specimen in the Lea collection which came from 

 Arkansas is not this species at all. 



'According to Marsh, who has examined the beak sculpture of Q. aaketvi. I have 

 never seen a specimen of the group in which it was not all eroded away. 

 Proc. N. M. vol. xxii 50 



