PALEONTOLOGY. 

 PLATE V . 



Page. 

 Trapezium bellefourchexsis 364 



Fig. 1. View of the left side of a specimen enlarged, showing the usual form. 



Fig. 2. Outline cardinal view of the same, slightly restored at the anterior extremity. 



Fig. 3. View of a right valve, imperfect, of a hroader form, and showing the cast of the 



anterior muscular imprint. 

 Fig. 4. View of the left side of a broad form, showing the outline entire, but imperfect over 



the body of the shell. 



Trapezium subequalis 365 



Fig. 5. View of a large left valve, natural size. 



Fig. 6. A right valve of slightly different form. 



Fig. 7. Enlargement of a similar right valve, but more constricted on the basal margin. 



Fig. 8. Outline cardinal view, restored from the last specimen. 



Mytilus whitei 360 



Fig. 9. View of a left valve of the ordinary size. 

 Fig. 10. Profile view of the same, looking upon the buccal side. 

 Fig. 11. View of a right valve, which is slightly more arcuate than Fig. 9. 

 Fig. 12. View of another left valve, which is even straighter than Fig. 9, and has a less 

 oblique hiuge. 



VOLSELLA PERTEXUIS 362 



Fig. 13. View of a left valve, natural size. 



Fig. 14. Profile view, constructed from separated valves. 



VOLSEIXA (MODIOLA) FORMOSA 361 



Fig. 15. View of a left valve of small size. 



Grammatop-on ixorxatus 359 



Fig. 16. View of a right valve, natural size, showing the prevailing form and size, also 



showing radiating strite. 

 Fig. 17. An enlarged view of a cast of a left valve, showing the hinge features as seen on 



the cast. 

 Fig. 18. Outline cardinal view as constructed from separated valves. 



Pl.El'ROMYA NEWTOXI 367 



Fig. 19. View of a left valve of the prevailing form. 

 Fig. 20. View of a larger right valve. 



Dosinia JURASSICA 373 



Figs. 21, 22. Views of left valves of the usual form and size. 



Fig. 23. Cardinal view of the specimen Fig. 22. 



Fig. 24. View of the cast of a right valve, showing the pallial line and sinus. 



Saxicava jurassica 376 



Fig. 25. View of an internal cast, natural size. 



Fig. 23. View, enlarged, of the left side of a specimen retaining a portion of the shell, and 



showing the pallial sinus on the cast. 

 Fig. 27. Enlarged cardinal view of the specimen, Fig. 25, showing the angularity of the 



umbonal ridge. 

 Figs. 28, 29. Enlarged cardinal and right views of a large individual, retaining a large 



part of the shell. 

 Fig. 30. View of one of the casts of the burrows as separated from the surrounding clayey 



matrix. 



PSAMMOBIA ? PREMATURA 374 



Fig. 31. View of the specimen described, which is an internal cast, showing the muscular 

 imprints and pallial line. 



ASTARTE (?) FRAGILIS 363 



Figs. 32, 33. Eight and cardinal views, enlarged, of a specimen which we have supposed to 

 belong to this species. 



Thracia ?' sublevis 375 



Fig. 34. View of a right valve referred to this species, by error on plate, made Fig. 24. 



Ne^sra longirostra 376 



Fig. 35. View of a left valve enlarged, showing the characters of the species. 



