﻿CRIST ARIA 22 S 



Barhala plicata H. and A. Adams, Gen. Rec. Moll., II, 1857, 



p. 501. pi. cxvir, figs. 4, 4ar. 

 Anodonta plicata Schrenck, Reis. und F. Am. Lande, II, 



1867, P- 704, pl- xxvii, fig. 4. 

 Anodonta (Dipsas) plicata Clessin, Conch. Cab. Anodonta, 



1876, p. 240, pl. XXI, figs. I, 2. 

 Cristaria plicata von Ihering, Abh. Senck. Nat. Ges., XVIII, 



1893, P- 147- — Simpson, Syn., 1900, p. 583. 

 Cristaria tuberculata Schumacher, Ess. Nov. Syst., 1817, p. 



140, pl. XX, fig. 2. 

 Anodonta dipsas Bi.ainviij.e, Man. Mai., 1825, p. 538, pl. 



LXVI, fig. 2. 



Symphynota bialata Lea, Tr. Am. Phil. Soc, 1830. p. 445, pl. 



XIV, fig. 24; Obs., I, 1834, p. 59, pl. XIV. fig. 24. 

 Ufiio bialata Hani.ey, Biv. Shells, 1843, P- 214, pl. xxii, fig. 4. 

 Barbala bialata Chenu, Man., 1859, p. 145, fig. 717. 

 Unio bialatus Deshayes, IV. Elem. Conch., 1839, p. 19, pl. 



XXXI, fig. 3; Tr. Elem., II, 1853, P- 218, pl. xxxi, fig. 3.— 



SowERBY, Conch. Icon., XVI, 1868, pl. xlvi, fig. 247. 

 Anodonta magnifica Clessin, Conch. Cab. Anodonta, 1873, P- 



123, pl. XXXV, fig. I. 



Barbala plicatula Retel, Conch. Sam., Ill, 1890, p. 175. 



I cannot say that the shells of this species are dimorphous, 

 though there are specimens which are fuller in the posterior 

 base than others. There is a considerable variation in the 

 form, some of them having a slightly rounded basal line; in 

 others it is incurved a little ; some are considerably narrower 

 in front while others are no wider behind, (leaving out the 

 wing), than they are at the anterior end. There is frequently 

 a single faint pseudocardinal in each valve. 



The form from Cambodia, which is referred to C. plicata, 

 is believed by Fischer to be dififerent, and it may be C. beliua. 



Cristaria occidentalis (Heude). 



Shell long elliptical, rather solid, subinflated, with a small 

 anterior wing and a larger irregular dorsal one; beaks sub- 

 compressed, their sculpture consisting of very faint, concen- 



