LIST OF ILLUSTRATIONS IN THE TEXT. 



Fig. Page 



1. Ophthahnosaurus : basioccipital and basisphenoid 5 



2. ,, exoccipital and supraoccipital 7 



3. „ pro-otic, opistliotic, and stapes 10 



4. „ reconstruction o£ the posterior region of the skull 12 



5. „ basisphenoid 13 



6. Ophthalmosaurus and Ichthyosaurus : basisphenoid 14 



7. Ophthalmosaurus : basisphenoid and parasphenoid 15 



8. „ squamosal and postorbitiil 17 



9. ,, quadrate 18 



10. „ quadrato-jugal and jugal 20 



11. „ lachrymal 21 



12. ,, nasal 22 



13. „ maxilla 23 



14. ., parietal 25 



15. „ part o£ upper region of skull 26 



1(). ,, postfrontul 27 



17. ,, pterygoid 29 



18. „ palatine (?) 29 



19. „ vomer 30 



20. „ posterior portion o£ right ramus o£ mandible 32 



21. „ surangular 33 



22. ,, articular 34 



23. „ restoration o£ skull and mandible 35 



24. „ centra o£ axis and atlas vertebrae 37 



25. ., centra o£ anterior cervical vertebrae 39 



26. ., dorsal and caudal vertebra3 40 



27. „ caudal vertebraj 41 



28. ,, caudal vertebrae 42 



29. ,, left half of neural arch of anterior cervical vertebrse 43 



30. „ neural arch of a dorsal vertebra 44 



31. ,, sections of vertebral centra and the upper end of a dorsal rib ... 45 



32. ,, coracoid 47 



33. ,, scapula 48 



