1404 ANODONTITES 



narrowed, rounded ; base line curved or rounded, often fuller 

 behind the middle ; dorsal slope obliquely truncate or subtrun- 

 cate ; posterior ridge low, with usually a shallow radial groove 

 just above it ; surface with more or less strongly developed 

 growth lines ; epidermis brownish to olive ; hinge edentulous ; 

 ligamental patch triangular, deep ; anterior scars well marked, 

 posterior scars faint ; nacre whitish or flesh-colored dull ; pris- 

 matic border wide on the base. 



Length 87, height 57, diam. t^J nmi- 



Length 81, height 59, diam. 32 mm. 



Southern South America, east of the Andes. 

 Anodonta patagonica Lamarck, An. sans. Vert., VI, 1819, p. 



88; Enc. Meth., 11, 1827, p. 147, pi. 203, fig. i. — Kuster, 



Conch. Cab. Ano., 1853, p. 50, pi. xii^ fig. 2. 

 Margarita (Anodonta) fyatagonica'LEA, Syn., 1836, p. 52; 1838, 



P- 31- 

 Anodon patagonica Catlow and Rhe\k, Conch. Nom., 1845, 



p. 67. 

 Margaron ( A)iodonta) patagonica LiiA, Syn., 1852, p. 51 ; 



1870, p. 82. 

 Glabaris patagonicus Simpson, Syn., 1900, p. 916. 

 Anodon trapc:zcus Spix, Test. Fluv. Bras., 1827, p. 28, pi. xx, 



fig. I. 

 Anodonta trapczeum d'ORP.iGNY, Voy. Am. Mer., J843, pp. 6, 



19. 

 Anodonta trapczca Kustkr, Conch. Cab. Ano., 1853, p. 7, pi. 1, 



fig- 3- 

 (Glabaris trapecea von Iherinc, Arch, fiir Naturg., 1893, p. 57. 



Anodonta lato-mqrginata I^ka, Tr. Am. Phil. Soc, V, 1834, p. 

 76, pi. XII, fig. 34; Obs., L 1834, p. 188, pi. XII. fig. 34. — 

 Hanlky, Biv. Shells, 1843, P- ^^i, pi. xxn^ fig. 14. — Chenu, 

 Man., II, 1859, p. 146, fig. 724. — Clessin, Conch. Cab. Ano.> 

 1873, p. 76, pi. XXI, figs. 3, 4. 



Margarita (Anodonta) lato-marginata Lea, Syn., 1836, p. 53; 

 1838, p. 31. 



Margaron (Anodonta) lato-marginata Lea. Syn., 1852. p. 51 ; 

 1870, p. 82. 



