Plate VI. 



Figures 1-6. Seven anterior cervical vertebrae of the type of P. ingens Marsh, No. 1175; 

 seen from the left side ; slightly restored, x 0.50 



Figure 1. Atlas and axis. 

 Figure 2. Third cervical. 

 Figure 3. Fourth cervical. 

 Figure 4. Fifth cervical. 

 Figure 5. Sixth cervical. 

 Figure 6. Seventh cervical. 



Figure 7. Seventh cervical vertebra of Pteranodon sp., No. 2692 ; seen trom the left side. 

 x 0.66 



Figure 8. Eighth cervical vertebra of the same individual ; seen from the left side ; 

 showing rib. x 0.66 



Figure 9. Ninth cervical vertebra of the same individual ; seen from the left side. 

 x 0.66 



Figure 10. Eighth cervical vertebra of the same individual ; anterior view, x 0.66 



Figure 11. Atlas and axis of the type of P. longiceps Marsh, No. 1177; seen from the 

 left side. < 1.0 



Figure 12. Atlas and axis of the type of P. ingens Marsh, No. 1175; seen from the rear. 

 x 0.66 



Figure 13. Fourth cervical vertebra of the type of P. ingens Marsh, No. 1175: anterior 

 view, x 0.50 



Figure 14. The same specimen ; posterior view, x 0.50 



Figure 15. Right rib of the ninth cervical vertebra of the type of P. ingens Marsh, 

 No. 1175; posterior view, x 0.50 



Figure 16. -Right rib of the ninth cervical vertebra of Pteranodon sp., No. 2692 ; anterior 

 view, x 0.66 



Figures 17-20. Four free dorsal vertebrae of Pteranodon sp.. No. 2616; seen from the 

 left side ; slightly restored, x 0.66 



Figure 21. First free dorsal vertebra of the foregoing series; anterior view, x 0.66 



Figure 22. The same vertebra ; posterior view, x 0.66 



Figure 23. Four caudal vertebrae of Pteranodon sp., No. 2546; seen from below, x 0.66 



