REFERENCES TO THE PLATES. " 127 



Fig. 11. Inferior view. 



Fig. 12. Lateral view. 



Figs. 13-15. A posterior lumbar vertebra. 



Fig. 13. Inferior view. 



Fig. 14. Lateral view. 



Fig. 15. End view. 



Figs. 16-18. A posterior lumbar vertebra, belonging to the same individual as Figs. 13-19, Plate V. 



Fig. 16. Inferior view. 



Fig. IT. Lateral view. 



Fig. 18. End view. 



PLATE VII. 



All the figures are reduced one-half the diameter of the originals, excepting Fig. 16, which is of 

 the natural size. 



Figs. 1-18. Vertebras of Mosasaurus. 



Figs. 19, 20. Vertebra of Macrosaurus. 



Fig. 1. Cervical vertebra of Mosasaurus, from Monmouth County, New Jersey. Posterior view. 

 a, Articular processes ; t, transverse process ; h, hypapophysis ; p, posterior convex surface of the 

 body. 



Fig. 2. Cervical vertebra, from Burlington County, New Jersey. Inferior view, a, Anterior 

 concave surface of the body ; p, posterior convex surface ; i, transverse process ; h, hypapophysis. 



Fig. 3. Posterior view of the same specimen as the last, t, Transverse process ; h, hypapophysis. 



Figs. 4-1. Vertebrae, from Columbus, Mississippi, belonging to Dr. Spillman. 



Fig. 4. Cervical vertebra. Inferior view, a, Anterior ; p, posterior. 



Fig. 5. Another cervical vertebra, from the same individual as the last. Lateral view, a. Anterior; 

 p, posterior surface of the body ; h, hypapophysis ; ar, articular process ; s, spinous process ; 

 t, transverse process. 



Fig. 6. Posterior view of the same specimen as the last, s, Spinous process ; a, articular process ; 

 t, transverse process ; h, hypapophysis. 



Fig. Y. Fragment of a dorsal vertebra, from the same individual as the last. Inferior view. 

 a, Anterior ; p, posterior ; t, transverse process. 



Fig. 8. Dorsal vertebra, from Monmouth County, belonging to Dr. C. Thompson. Posterior view. 



Figs. 9-11. Lumbar vertebra, from Burlington County, New Jersey. 



Fig. 9. Inferior view. 



Fig. 10. Lateral view. 



Fig. 1 1. Posterior view, a, Anterior ; p, posterior ; i, transverse processes. 



Fig. 12. Another lumbar vertebra, from Burlington County. Lateral view. 



Fig. 13. Lumbar vertebra, from Freehold, Monmouth County. Lateral view. 



Fig. 14. Posterior view of the same specimen, t, Transverse process. 



Fig. 15. Portion of a series of posterior caudal vertebra imbedded in a mass of rock, from the 

 Yellowstone River, Nebraska. Lateral view, a, Anterior ; p, posterior ; s, spinous processes ; 

 c, chevron bones. 



Fig. 16. A posterior caudal vertebra, from the same individual as the last. Lateral view. Natural 

 size, a, Anterior ; p, posterior part of the body ; v, vertebral arch ; c, chevron bone. 



Fig. lY. Body of a posterior caudal vertebra, from the Cheyenne River, Nebraska. Lateral view. 

 a, Anterior ; p, posterior ; v, abutment of the vertebral arch ; c, abutment of the chevron bone. 



Fig. 18. Posterior view of the same specimen as the last. 



Fig. 19. Supposed vertebra of Ilacrosaurus, from Freehold, Monmouth County. Inferior view. 

 a, Anterior concave surface of body ; p, posterior convex surface ; t, transverse processes. 



Fig. 20. Posterior view of the same specimen as the preceding. 



