612 PROCEEDINGS OF THE ACADEMY OF [Oct., 



Explanation of Plate XXXVIII. 



Fig. 1. — Aeipenser breniro strum Le Sueur. Type (?). Upper figure to left- 

 dorsal view of head; upper figure to right ventral view of head; lower 

 figure a lateral view. 



Fig. 2. — Lepisosteus huronensis (Richardson). Warren Co., Pa. 



Figs. 3,4. — Lepisosteus osseus (Linnseus). • Type of Lepidosteus crassus Cope. 



Fig. 5. — Lepisosteus treculii (Dumdril). Ohio River. 



Fig. 6. — Lepisosteus clintonii (Dumeril). Delaware River below Trenton. 



Fig. 7. — Cylindrosteus platostomus (Rafinesque). "North America " 



Figs. 8, 9. — Cylindrosteus scabriceps Fowler. Type. 



Figs. 10,11. — Cylindrosteus productus Cope. Type. 



Fig. 12. — Cylindrosteus agassizii Dumeril. North America. 



Figs. 13, 14. — Cylindrosteus castelnaudii Dumenl. West coast of Florida. 



Figs. 15, 16. — Cylindrosteus megalops Fowler. Type. 



Fig. 17. — Cylindrosteus tristcechus (Schneider). Mississippi River, La. 



Fig. 18. — Cylindrosteus tropicus (Gill). Nicaragua. 



