PLATE 34. 

 Fig. 1. 189. 1. NucuLA LEV ATA. ' (Pag. 150.) 



1 «, h. Left valve and posterior view of a specimen of the prevailing form in New-Yorl^. Tlie muscular im- 

 pressions t t are distinctly visible. 

 1 c, d. Similar views of a large shell, slightly varying in its proportions. 

 1 e. Left valve of a very gibbous specimen, in which the posterior side is less extended. 

 1 f. A specimen less elevated, and approaching the western forms. 



1 g. Cast of a western specimen, showing more distinctly the muscular impressions f t- 

 1 h. Cardinal view of the same, showing the crenulations of the hinge, and the same enlarged. 

 1 i. A small .specimen of the same, with the shell showing faint concentric lines. 



1 /c. Cardinal view of a gibbous specimen. 



Fig. 2. 190. 2. NucuLA poststriata. (Pag. 151.) 



2 a. Right valve of Ibis species. 2 b. Cardinal view of the same specimen. 



Fig. 3. 191. 1. Tellinomya nasuta. (P^g- 152.) 



3 a. Right valve of a .specimen on which the shell is preserved. 



3 h. Similar view of a cast, showing the muscidar impression a. 3 c. Dorsal view of the same. 



Fig. 4. 192. 2. Tellinomya sanguinolaroidea. (P^g- 152.) 



4 a. Right valve, showing the posterior muscular impression a. 4 b. Cardinal view of the same specimen. 



Fig. 5. 193. 3. Tellinomya gibbosa. (Pag. 153.) 



f) a. Right valve of this species. 5 6. Dorsal valve. 



Fig. 6. 194. 4. Tellinomya dubia. (Pag. 153.) 



6 a. Cardinal view of the two valves in connection. ('> b. Left valve of the same, slightly contracted behind. 

 c. A separate valve, in which the posterior contraction is scarcely perceptible. 

 d. Left valve of a specimen, in which the posterior side is much contracted. 

 6 e,f. Separate valve of an old shell, with a view of the dorsal margin. 



Fig. 7. 195. 5. Tellinomya anatiniformis. (Pag. 154.) 



Fig. 8. 196. 1. Cardiomorpha vetusta. (Pag- 154.) 



Fig. 9. 198. 2. Edmondia subtrttncata. (Pag. 156.) 



Fig. 10. 209. 10. MoDioLOPSis? trentonensis. (Pag. 161.) 



