149 



identified by Professor Baird and Mr. R. Kennicott, and the speci- 

 mens are deposited in the museum of the Smithsonian Institution. 



1. Trionyx. Yellow-stone river. 



2. Emys elegans. Yellow-stone river. 



3. Emys. Mouth Powder river. 



4. Cistudo. Mouth Powder river. 



5. CrofaJus confluentus^ Say. Yellow-stone river. 



6. Crotalopliorus fergeminus, Holb. Yellow-stone river. 



7. Entainia sirfalis, var. parietalis, B. & G. Loup Fork. 



8. Entainia. Sand Hills. 



9. Nerodia sijjedon, B. & G. Yellow-stone river. 



10. Heterodon nasicus, B. & G. Sand Hills of Loup Fork. 



11. Pituoplds sayi, B. & G. Sand Hills of Loup Fork. 



12. Amphiholus sayi. Fort Benton, on Missouri river. 



13. Bascanion fiaviventris. Head of Loup Fork. 



14. CMorosoma vernalis. Yellow- stone river. 



15. Scehphorus consobrinus. 



16. Scelophonts graciosus. * 



17. HolbrooTxia macidata. 



18. Holbrookia douglassi. 



19. Cnemidoplioms sexlineatus. 



20. Plestiodon lepfogrammiis. 



21. Plestiodon multivirgatum. 



22. Plestiodon inornatum. 



23. Plestiodon septentrionalis. 



24. Rana hcdecina. 



25. Bufo americanus. 



26. Bufo cognatm. 



27. Bufo woodhousi. 



28. Siredon. 



RECENT MOLLUSCA. 



An interesting series of recent fluviatile and land Mollusca were 

 secured during the several expeditions from various portions of the 

 upper Missouri. The fresh water shells were very kindly examined 

 by Mr. Isaac Lea, the celebrated conchologist, of Philadelphia. In 

 some remarks before the Philadelphia Academy in regard to the above 

 collection, and one obtained by Mr. Kennicott from the Red river of 

 the north, Mr. Lea says : 



" It is not to be understood that either of these collections, made 

 under adverse circumstances, and at times of great personal danger, 

 should be full representatives of this branch of the fauna of these 

 countries. But they are sufficient to prove that zoological life, so far 

 as represented by molluscs, is nearly, if not quite the same, as that 

 of the Ohio river basin, as well as that of the Missouri river and a 

 part of the lower Mississippi and Red river of the south. The know- 

 ledge of a part of the species from these remote districts proves tons 

 the wide spread distribution of the same species, as we find every onto 

 of them in the Ohio river at Cincinnati, Marietta, and Pittsburg, and. 



