778 PROCEEDINGS OF THE SAT1OXAL Ml'fiKfM. VOL.XXII. 



* Unio iragosua HAXLEY, Tost. Moll., 1842, p. 178; * Biv. Shells, 1813, p. 178, pi. xx, 



fig. 40.' * CATLOW and REEVE, Conch. Nom., 1845, p. 64. 



Ohio, Cumberland, and Tennessee river systems; westward probably 

 to Minnesota, Nebraska, and Kansas. 



tQUADRULA FORSHEYI Lea. 



* Unio forsheyi LEA, Pr. Ac. N. Sci. Phila., Ill, 1859, p. 155; * Jl. Ac. N. Sci. Phila., 



IV, 1860, p. 357, pi. LX, iig. 182; *Obs., VIII, I860, p. 39, pi. LX, fig. 182. 



* REEVE, Couch. Icon., XVI, 1864, pi. vi, fig. 21.* B. H.WRIGHT, Check List, 

 1888. *P.I-:TEL, Conch. Sam., Ill, 1890, p. 153. 



* Margaron ( Unio) forsheyi LEA, Syn., 1870, p. 32. 



Alabama to Texas, in streams flowing into the Gulf of Mexico. 



tQUADRULA SPECIOSA Lea. 



* Unio speciosus LEA, Pr. Ac. N. Sci. Phila., VI, 1862, p. 168; " Jl. Ac. N. Sci. Phila., 



V, 1862, p. 207, pi. xxxi, fig. 276; *0bs., IX, 1863, p. 29, pi. xxxi, fig. 276. 



* SOWERBY, Conch. Icon., XVI, 1868, pi. LXXXIV, fig. 447.* B. H. WRIGHT, 

 Check List, 1888. * P.ETEL, Conch. Sam., Ill, 1890, p. 168. 



* Margaron ( Unio) speciosus LEA, Syn., 1870, p. 33. 



Kansas, south to Texas. 



t QUADRULA APICULATA Say. 



* Unio apiculatus SAY, New Harm. Diss., II, No. 2, 1829, p. 309; * Am. Conch., VI, 



1834, pi. Lii. 2 * CONRAD, New F. W. Shells, 1834, p. 67.* FERUSSAC, Guer. 

 Mag., 1835, p. 27.* CONRAD, Monog., IX, 1837, p. 78, pi. XLIV, fig. 1.* HAN- 

 LEY, Test. .Moll., 1842, p. 178; * Biv. Shells, 1843, p. 178, pi. xxm, fig. 51. 



* CATLOW and REEVE, Conch. Nom., 1845, p. 55. * CONRAD, Pr. Ac. N. Sci. 

 Phila., VI, 1853, p. 245.* H. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 497. 



* CIIENU, Manual, 1859, II, p. 142, fig. 696. * REEVE, Conch. Icon., XVI, 1864, 

 pi. in, fig. 11. *B. H. WRIGHT, Check List, 1888. * P.ETEL, Conch. Sam., Ill, 

 1890, p. 144. 



* Margarita ( Unio) apiculatus LEA, Syn., 1836, p. 15 ; 1838, p. 15. 



* Margaron ( Unio) apiculatus LEA, Syn., 1852, p. 22; 1870, p. 33. 



I 'io nobilis CONRAD (part), Jl. Ac. N. Sci. Phila., 1854, p. 297, pi. xxvn, figs. 2, 3. 3 



Louisiana to Texas. 



tQUADRULA RUMPHIANA Lea. 



* Unio rumphianus LEA, Tr. Am. Phil. Soc., X, 1852, p. 276, pi. xxn, fig. 34; Obs., 



V, 1852, p. 32, pi. xxn, fig. 34. ^CONRAD, Pr. Ac. N. Sci. Phila,, VI, 1853, p. 

 257.* H. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 497. B. H. WIUGIIT, 

 Check List, 1888.* PJETEL, Conch. Sam., Ill, 1890, p. 166. 



* Margaron ( Unio) rumphianus LEA, Syn., 1852, p. 21 ; 1870, p. 33. 



i*Unio blandianus LEA/ Pr. Ac. N. Sci. Phila., VIII, 1856, p. 263; * Jl. Ac. N. Sci. 



1 Written tragosus in text, no doubt a typographical error, as it is written cor- 

 rectly in the explanation of the plate. 



2 Say says that U. asper Lea is the same as his apiculatus. I think he is wrong. 



3 One specimen figured (fig. 2) is Q. apiculata. The other (fig. 3) is a nondescript, 

 possibly Q. asper, or it may be the form of Q. lachrymosus which I have placed under 

 var. lunulatus Pratt. 



Certain forms of riimphianus are very different from blandianus, being more 

 inflated, and showing a high, biangulate posterior ridgo and a deep radial sinus in 

 front of it, while specimens of the latter are much less in Hated and have alow, some- 

 what rounded, posterior ridge. But the difference between the two seems to be 

 absolutely briged by intermediate specimens. 



