TAB. XII. 



Fig. 



1. Lucina borealis, j<zye 139. 



2. Diplodonta astartea, p. 146. 



3. Diplodonta rotun data, p. 144. 



4. Loripes divaricata, p. 137. 



5. Diplodonta dilatata, p. 145. 



6. Lucina decorata, JP. 141. 



7. Lucina crenulata, p. 140. 



8. Kellia suborbicularis, p. 118. 



a. orbicular variety, left valve. 



b. transverse ditto, right valve. 



9. Kellia orbicularis, p. 120. 



a, b. interiors of both valves mag- 

 nified. 



c. outside view, natural size. 



10. Kellia coarctata, p. 123. 



Fig. 



11. Kellia ambigua,jfl. 120. 



a. trigonal variety. 



b. elliptical ditto. 



12. Montacuta substriata, p. 128. 



13. Kellia elliptica, p. 121. 



b. united valves, showing the sinu- 

 ated form of hinge margin. 



14. Montacuta ferruginosa, j. 129. 



15. Kellia pumila,jo. 124. 



16. Montacuta truncata, j0. 127. 



17. Montacuta bidentata, jo. 126. 



18. Hippagus verticordius, p. 150. 



19. Cryptodon ferruginosum, j. 135. 



20. Cryptodon sinuosum, /. 134. 



The lines indicate the size of the specimens. 



