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The great lignite tertiary "basin differs from the tertiary basin of 

 White river, "by its numerous beds of lignite, more or less pure, and 

 by the extent and beauty of its fossil flora. Some of the beds of 

 lignite are seven feet in thickness, but they usually vary from two to 

 four feet. The collection of fossil plants from this deposit is very 

 fine, consisting of nearly fifty species, all of which are as yet un- 

 described, but are supposed to be new to science. Many of the 

 leaves strongly resemble those of existing forest trees, and seem to 

 belong to the genera Platanus, Acer, Ulmus, Alnus, Populus, 

 Betula, Shulex, &e. The mollusca consist of land and fresh water, 

 with a few estuary shells. These have all been described, and 

 drawings made. Five species of vertebrata have been discovered in 

 this deposit. The following species of organic remains have, up to 

 this time, been described from this basin. 



VERTEBRATA. 



1. Thespesius occidentalis, Leidy. 



2. Ischyrotherium antiquum, Leidy. 



3. Mylognatlius priscus, Leidy. 



4. Compsemys victus, Leidy. 



5. Emys obscurus, Leidy. 



MOLLUSCA. 



6. Cydas formosa, Meek and Hay den. 



7. Cydas fragilis, Meek and Hay den. 



8. Cydas suhellipticus , Meek and Hayden. 



9. Cyrena moreauensis, Meek and Hayden. 



10. Cyrena intermedia, Meek and Hayden. 



11. Corhula mactriformis, Meek and Hayden. 



12. Unio priscus, Meek and Hayden. 



13. Bulimus teres, Meek and Hayden. 



14. Bulimus vermiculus, Meek and Hayden. 



15. Bulimus limneaformis, Meek and Hayden. 



16. Bulimus Nehrascensis , Meek and Hayden. 



17. Pupa helicoides, Meek and Hayden. 



18. Limnea tenuicosta, Meek and Hayden. 



19. Pliysa longiuscida. Meek and Hayden. 



20. Pliysa rhomhoidea, Meek and Hayden. 



21. Pliysa Nehrascensis, Meek and Hayden. 



22. Planorhis suhumbilicatus, Meek and Hayden. 



23. Planorhis convolutus, Meek and Hayden. 



24. Planorhis fragilis, Meek and Hayden. 



25. Velletia (Ancylus) minufa, Meek and Hayden. 



26. Paludina multi lineata. Meek and Hayden. 



27. Paludina Leai, Meek and Hayden. 



28. Paludina rctusa, Meek and Hayden. 



29. Paludina peculiaris. Meek and Hayden. 



30. Paludina trocliiformis, Meek and Hayden. 



31. Paludina Leidyi, Meek and Hayden. 



