PLATE XVIII. 



Fragments of shells of tortoises, natural size. 



g. 1. — Plastomenus trionychoides. Costal bone, above ; a, edge. Page 123. 



g. 2. — Plaslomemw viuUiforeatiit. Costal bone, above. Page 124. 



g. 3-C. — Bones of one individual of I'lagtommus muUifoveatus. Page 124. 



gs. 3,4. — Boues of plastron. 



g. C. — A vertebral boue, from above ; a, from below. 



gs. 7,8. — Bones of a third individual of P. muUifoveatug, from the plastron. Page 124. 



gs. 9-14. — Bones of one individual of P. molopinus ; a, inferior, and ft, marginal views. Page 125. 



gs. 9-13. — Median costal bones. 



g. 14. — Proximal angle of last costal bone. 



gs. 10-17. — Fragments of carapace of Plastumenus ailemiua; o, inferior views. Page 126. 



gs. 15, 16. — Lateral costals. 



17. — Last costal, entire, showing absence of vertebral or pygal bones, 

 gs. 18, 19. — Marginal bones of Anostira raduHna; a, edge views. Page 128. 

 g. 18. — Anterior marginal, 

 g. 19. — Posterior marginal. 



gs. 20-22. — Bones of carapace of Kmys })ohjc>jphu8 ; a, side views. Page 131. 

 gs. 20, 21. — Vertebral boues. 



g. 22. — A marginal bone, showing pit for gomphosis. 

 gs. 23-25. — Carapace and plastron of ICmys lerreslria. Page 131. 

 g. 23. — Vertebral bone; o, edge view. 



g. 24.— Clavicular (or episternal) bone, from above; a, from below. 

 g. 25. — Costal bone; u, Ironi below ; b, edge, 

 gs. 215-33. — Bones of liniye viegaulax. Page 132. 

 gs. 26-28. — Vertebral bones, 

 gs. 29-31. — Marginal boues; a, edges. 

 gs. 32, 33. — Bones of a second individual, 

 g. 32. — Vertebral bone, 

 g. 33. — Costal bone ; o, edge view. 



gs. 34-42. — Bones of Emys eullmetu), found together. Page 133. 

 gs. 34-36. — Vertebral bones, 

 gs. 37-40. — Marginal bones; a, edges. 



g. 41. — Clavicular or episternal bone, from below ; a, from above. 

 g. 42. — Part of postabdominal. 



