TAB. XXII. 



Fig. 



1. Tellina Balthica, p. 231. 



a, b, specimen from Clacton, found in clay, with Unio littoralis. 

 c, specimen from Mam. Crag of Norfolk. 



2. Psammobia vespertina, p. 222. 



a, d, representation of a monster valve from Sudbourne. 

 c, d, specimen from Ramsholt. 



3. Psammobia Ferroensis, p. 221. From Coralline Crag, Sutton. 



4. Psammobia Tellinella, p. 223. 



5. Tellina donacina, p. 233. 



6. Tellina donacilla, p. 234. 



7. Donax vittatus, p. 219. From Mam. Crag, Bramerton. 



8. Donax trunculus, p. 219. From Red Crag, Sutton. 



9. Donax politus, p. 220. From Coralline Crag, Sutton. 



10. Abra alba, p. 237. 



c, enlarged hinge of right valve. 



11. Abra obovalis, p. 240. 



c, enlarged hinge of right valve. 



12. Abra fabalis, p. 238. From Red Crag, Walton Naze. 



13. Abra prismatica, p. 239. From Coralline Crag, Sutton. 



14. Trigonella plana, p. 235. 



a, c, show difference of form in palleal impression. 



