TAB. XXI. 
Fig. 
1. Tellina crassa, p. 226. From Red Crag, Sutton. 
e, portion of surface enlarged. 
2. Tellina Benedeni, p. 230. From Red Crag, Sutton. 
a, 6, show similarity of form in siphonal scar. 
d, shows the equal tumidity of the two valves. 
The siphonal side of fig. 2 a, was filled up by mistake ; the specimen from which 
the figure was taken is imperfect, extending only to the fracture. 
3. Tellina fabula, right valve, p. 232. 
4. Tellina balaustina, p. 227. From Coralline Crag, Sutton. 
d, enlarged portion of surface. 
5. Tellina pretenuis, p. 230. From Red Crag, Sutton. 
6. Tellina lata, p. 228. i us 
7. Tellina obliqua, p. 228. ey Bs 
4, c, show the dissimilar forms of the siphonal scar. 
Note. This plate was engraved March, 1854. 
