167 St. Maurice and Ciaiborne Pelecypoda 167 



Tellina alta Conrad, PI. 50. Fig- 22 



T. alta Con., Foss. Sh. Tert. Form., 1833, p. 41. 

 T. alta Con., Amer. Jr. Sci., vol. i, 1846, p. 399, pi. 4, fig. 10. 

 T. (Arcopagia) alta Con., Amer. Jour. Conch., 1865, p. 5. 

 T. {Arcopagia) alta Dall, Trans. Wag. Ill, 1900, p. 1015. 



Conrad's original description. — Shell suborbicular orsuboval, equi- 

 lateral, convex, with prominent, acute, concentric striae, and concave inter- 

 vening spaces, and with minute radiating lines, lunule small ; lanceolate 

 slightly impressed ; cardinal teeth and anterior lateral tooth compressed 

 and prominent : posterior lateral tooth small but distinct. 



In the Journal of 1846, cited above, Conrad modifies his de- 

 scription somewhat as follows : Suborbicular, inequivalved, in- 

 equilataral, with lamelliform concentric lines, not closely ar- 

 ranged, and minute closely arranged radiating wrinkles ; poster- 

 ior side obtusely folded, the inferior margin truncated obliquely 

 inwards ; lateral teeth distinct, the posterior one very short, 

 pyramidal, remote. 



In this species one valve is considerably more convex than 

 the other, and the anterior muscular impression is rather deeplj^ 

 impressed, and bounded on the inner side by a broad rib-like el- 

 evation, which extends to the apex. 



The specimens at the Academy, presumably the types of this 

 species, are much more coarsely striate than is raveneli, and are 

 more circular in outline. Whether, however, they are mere ex- 

 treme variations of the latter from the St. Maurice beds at the 

 base of the bluff or are really representatives of another species 

 from the "sand" above, we are not able to state at present. None 

 of our specimens appear to be clearly referable to this species. 



Tellina raveneli Conrad, PI. 51, Figs- i-5 



T. raveneli Con., Amer. Jour. Sci., vol, i, 1846, p, 400. 



T. {Arcopagia) raveneli Con., Amer. Jour. Conch., 1865, p. 5. 



T. {Arcopagia) raveneli Dall, Trans, Wag., Ill, 1900, p, 1016. 

 Conrad's original description.— Suhoval, inequilateral, moderately 

 thick, with very fine regular concentric lines and with brown bands; anter- 

 ior margin obliquely truncate above ; posterior side obtusely folded ; beaks 



