﻿426 ANODONTA 



L inbonal ricl.^e angular, beaks nut high, with doublc-l'jop 

 sculpture, as in .liiu. grandis Say. 



Umbos inriated, greatest diameter of the shell about 1/3 

 from beak to base. 



Length 3, height i.S, diam. 1.6 inches." (Frierson). 



Type localitN. I'lvers I'oini. Clear hake. Deuel Co., South 

 Dakota. 

 Auodonta dakota V\<\\:\<m>\ , Xaut.. XX ill. i<»ic^ i). 113, pi. x. 



"The beaks ally the shell, of course, to .Inodonta grandis 

 Say. It is nearest to that form called by Mr. Anthony A. 

 siibgibbosa (and especially to the figure of this species shown 

 in the Conchologia Iconica. which is much more characteristic 

 than the figure in the American Journal of Concholog>). 

 From any form of Ano. grandis it dififers in being more cylin- 

 drical ; /. c, in lacking the sw^elling "amidship" so often shown 

 by A. grandis; in being rayless (so far as known), but espe- 

 cially by having its posterior point not elevated above the basal 

 line, and by the marked truncation posteriorly, which trunca- 

 tion is as marked as in Margaritatia niarginata Say, and the 

 straight posterior, and the resulting quadrilateral aspect of 

 the shell. It is more quadrate than .Inodonta doliaris Lea. 

 The lack of any obliquity is remarkable." 



Anodonta bealki Lea. 



Shell oblong, irregularly elliptical, thin but strong, subin- 

 fiated, inequilateral, with full, somewhat elevated beaks, whose 

 sculpture consists of corrugated, doubly-looped ridges that 

 are subnodulous at the bases of the loops ; posterior ridge low, 

 ending in a point on the median line behind ; dorsal wing low ; 

 the posterior slope subtruncate ; dorsal and ventral borders 

 nearly ])arallel : surface nearly smooth ; epidermis ashy-brown, 

 banded, greenish in young shells, there being two or three 

 dark rays on the posterior slope, the whole shining ; nacre 

 bluish-white, very slightly thickened in front. 



Length of type 80. height 42. diam. 30 mm. 



Length of larger shell 93, height 50. diam. 35 mm. 



Te.xas to Kansas. 



Type locality, Leon County and \ erdigris River, Texas. . 



