﻿ANODONTA 417 



tened, their sculpture, consisting of numerous ridges, curved 

 in front and nearly following the growth lines, then running 

 backward in an almost straight line and ending at the low 

 posterior ridge. 

 Animal unknown. 



Anodonta arcfformis (Heude). 



Shell long elliptical, inflated, with dorsal and ventral lines 

 nearly parallel ; posterior ridge low, angled, ending behind in 

 a point on the median line ; beaks placed a little in front of 

 the middle, very full but not high, with numerous rather high, 

 strongly curved ridges, parallel with the growth lines in front 

 and running out nearly straight behind ; dorsal wing small, 

 truncated obliquely behind ; surface with delicate growth lines ; 

 epidermis ashy-green with two or three rays on the posterior 

 slope : nacre white, slightly iridescent. 



Length 90, height 50, diam. 45 mm. 



Canal of Song-Kiang-fou, China. 

 Anodon arccrfoniiis Hkude, C. F. Nank., Ill, 1877, pi. xix, fig. 



40. 

 Anodonta arcccformis P.TvTEL, C. Sam., III. 1890, p. 176. — 



Simpson, Syn., 1900. p. 641. 



A remarkably cylindrical form, having full, but not high, 

 beaks. 



A^ar. Htn'otincta von Martens. 



"Shell decidedly smaller and ])roportionately lower. Beaks 

 not projecting at all, broadly flattened, with some undulating 

 ridges ; postero-dorsal angle not projecting at all, ventral mar- 

 gin more decidedly curved in front than behind. Epidermis 

 pale grayish-green, somewhat shining, with one or more black- 

 ish growth lines. Nacre bluish-white, very shining, with a 

 rather broad dull ochre-yellowish colored zone near the mar- 

 gin. 



Length 49, height at beaks 27, at wing 23 ; diam. 19 mm." 

 (von Martens.") 



Type locality, Soeul, Province of Kyoengkwido and Keum- 

 gang, near Kongju, Province of Chungchoengdo, Korea. 



