87 St. Maurice and Claiijornk Pelecypoda 87 



The specimen is still in the Academy's Collection and is a 

 small a//iros/afa-\\ke form with the median portion of the rib thin, 

 or highly keeled. We suppose this to represent the St. Maurice 

 horizon. 



Venericardia inflatior Mej er, PI. 31. Fig. 6. 



/'. injJatior Mej-er, Amer. Jour. vSci., vol. 29, 1885, p. 460. 



/'. iiijlatior viewer. Bull, i, Geol. Surv. Ala., 1886, p. 84, pi. i, fig. 26. 



Cardita parva Cossmann, Notes Compl. &e., 1893, p. 14. 



Meyer's original description. — Small ; cordate ; ventricose ; sub- 

 equilateral ; margin semicircular ; beaks elevated and large, turned anter- 

 iorh- ; surface covered with about twenty ribs ; they are smooth at the um- 

 bo, slightly crenulated towards the ventral margin ; the interstices are 

 about of the same size as the ribs ; margin crenulated. 



Locality. — Claiborne, Ala. 



Differs from I 'enericardia parva Lea, from the same locality princi- 

 pally in being smaller, more ventricose and rounded, and having a much 

 larger beak. 



We have found nothing in our collections corresponding to 



this. Its appearance is more or less pathologic. 



Venericardia (Pleuromeris) tortidens, n. sp., PI. 31. Figs. 12 a, b. 



Specific characterization. — Form and size as indicated by the 

 illustrations and explanation ; substance of the shell rather thin, 

 showing within clearly the position of the ribs ; exterior with 

 14-15 beaded ribs about Vi the width of the interspaces ; ribs not 

 terraced laterally, but becoming broader at base and having a 

 width more than equal to the width of the deepest portion of the 

 interspaces ; lunule comparatively large and prominent, muscu- 

 lar scars very faint, hinge in the left valve with a small, forward- 

 downward sloping cardinal, with traces of a lateral at the distal 

 end of the lunular mass, a long posterior extending ^ way to 

 the posterior end of the shell : right valve with an anterior sock- 

 et y'z way toward the anterior end of the shell, one small and one 

 large cardinal with a posterior lateral forming a continuation of 

 the ligamental support. 



The general appearance of this shell is similar to the young 

 of V. planicosta, but the ribs are very few in number, show no 



