NO. 1205. SYNOPSIS OF THE NAIADES SIMPSON. 665 



Animal with the marsupium occupying the whole of the outer gills, 

 very thick, like that of Anodonta; inner gills free all or the greater part 

 of their length from the abdominal sac; branchial opening papillose; 

 1 opening generally smooth or only slightly creuulate. 



tSYMPHYNOTA COSTATA Rafinesque. 



Alasmidonla costata RAFINESQUE, Ann. Gen. Sci. Brux., V, 1820, p. 313, pi. 



LXXXII, figs. 15, 16. 

 ^ Alasmodonta costata SAY, Am. Conch., VI, 1834. * COXRAD, New F. W. Shells, 



1834, p. 72. *FEUt;ssAC, Guer. Mag., 1835, p. 25 

 "Complanaria costata COXRAD, Pr. Ac. N. Sci. Phila., VI, 1853. p. 261. 



* Alasmodonta ruf/osa BARNES, Am. Jl. Sci., VI, 1823, p. 278, pi. xm, fig. 21. 



SHORT and EATOX, Transylvania Jl., 1831, p. 81. * C. B. ADAMS, Thompson's 

 Hist, of Vt., 1842, p. 165. * BAKER, Moll. Chicago, Pt. 1, 1898, p. 57, pl.vn, 

 tigs. 1, 2; vin, figs. 3, 4. 

 * Mya rugosa EATOX, Zool. Text-Book, 1826, p. 222. 



* Margarita (Margaritana) rugosa LEA, Syn., 1836, p. 44 ; 1838, p. 27. 



* Unio rugosa HANLEY, Test. Moll., 1842, p. 211 ; * Biv. Shells, 1843, p. 211, pi. xxi, 



fig. 8. 



*Alasmodon rugosa DE KAY, Zool. N. Y., Pt. 5, 1843, p. 196, pi. xiv, fig. 226. 

 *Complanaria rugosa STIMPSOX, Shells of N. Eng., 1851, p. 14. 

 Margaron (Margaritana) rugosa LEA, Syn., 1852, p. 42; 1870, p. 67. 



* Baplria rugosa H. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 500. 



* Margaritana rugosa CALKIXS, Pr. Ottawa Ac. Sci., 1874, p. 46. * B. H. WRIGHT, 



Check List, 1888.* P.ETEL, Conch. Sam., Ill, 1890, p. 164. 



* Lasmigona rugosnm RAFIXESQUE, Cont. Mon., Og,, 1831, p. 5. 



* Unio rugosus CATLOW and REEVE, Conch. Norn., 1815, p. 63. KUSTER, Conch. 



Cab. Unio, 1861, p. 200, pi. LXVI, figs. 1-3. SOWERBY, Conch. Icon., XVI, 1867, 

 pi. LX, fig. 302. 

 Alasmodonta hians FERUSSAC, Guer. Mag., 1835, p. 25. 



Mississippi drainage generally; St. Lawrence basin ; Manitoba; Hud- 

 son liiverf; Columbus, Mississippi. Texas?. 



Subgenus PTEROSYGNA Eafinesque, 1831. 

 (Type, Alasmodonta complanala Barnes.) 



Shell large, ovate-rhomboid, inflated in post basal region ; beaks much 

 compressed, their sculpture sharply and strongly doubly looped; epi- 

 dermis dark, scarcely rayed; teeth very heavy. 



Animal with an extremely thick marsupium; palpi large; mantle with 

 small crenulatious on lower border; branchial opening large; anal open- 

 ing small, both slightly papillose. 



tSYMPHYNOTA COMPLANATA Barnes. 



* Alasmodonta complanata BARXES, Am. Jl. Sci., VI, 1823, p. 278, pi. xm, fig. 21. 



"HII.DRETH, Am. Jl. Sci., XIV, 1828, p. 289. * CONRAD, New F. W. Shells, 



1834, p. 72.* SAY, Am. Conch., VI, 1834.* BAKER, Moll. Chicago, Pt. 1, 1898, 



p. 60, pi. vin, figs. 1, 2 ; ix, figs. 1-4. 

 k My a complanata EATOX, Zool. Text-Book, 1826, p. 222. 

 *Symphynota complanata LEA, Tr. Am. Phil. Soc., Ill, 1830, p. 448. * SHORT and 



EATOX, Transylvania Jl., 1831, p. 80. * LEA, Obs., I, 1834, p. 62. FERUSSAC, 



Gner. Mag., 1835, p. 25. 



