280 [Oct. 1847. 



kindness of Dr. Storer, the original of the occipito-maculatus* which corres- 

 ponds with the animal described in many particulars. The form of the head 

 and neck is the same, as are also the plates immediately in front of the eye, 

 which are two in number, the Tripidonatus Dekayi, with which it has been 

 considered identical, presenting but one. The scales are likewise carinated and 

 bi-punctate posteriorly, and the number of caudal and abdominal plates is 

 nearly the same in both. The specimen of Dr. Storer, however, is much more 

 slender, and the coloration is almost totally different, which, however, may 

 be the effect of long immersion in spirits. We are inclined to the opinion, 

 therefore, that notwithstanding the great difference in their size and coloration, 

 the two animals are the same. 



My friend Prof. Baird, to whom I exhibited the specimen brought by Mr. 

 Moss, states that it is very abundant in the north, being, in fact, the most 

 common snake along Lake Champlain. In Troy, he observes, " I have found 

 one, and have a specimen from Georgia, at least given me as from that local- 

 ity." It is certainly remarkable, that an animal having so wide a geograph- 

 ical distribution, and presenting the beautiful appearance which it does, should 

 be so little known to naturalists. 



The Committee on Mr. Conrad's paper, read 12th inst., re- 

 ported in favour of publication in the Proceedings. 



Observations on the Eocene formation, and descriptions of one hundred and five 

 new fossils of that period, from the vicinity of Vicksburg, Mississippi, with an 

 Appendix. 



By T. A. Conrad. 



In the Spring of 1844, I collected about 109 species of Eocene fossils, most 

 of which appear to be new species. There are 60 univalves, 42 bivalves, and 

 1 multivalve shell, and 6 or 7 polyps. 



Of these fossils, I can identify two only with species of the Claiborne sands, 

 Infundibulum trochiformis aud Conus saurodens. Very few others are related to 

 species of the Alabama sand strata ; Lucina Mississippiensis, Sigaretus Missis- 

 sippiensis and Dentalium Mississippiensis, are the only shells which might be 

 confounded with species of those deposits. 



The Vicksburg group contains three species of bivalves which have much 

 resemblance to Miocene fossils of this country. Lima staminea approaches L. 

 papyria; Corbula engonata is allied to C. inequalis, Say; and Nucula Vicks- 

 burgensis, to N. obliqua, Say. 



I have not observed a recent species in this group, and yet it is decidedly 

 more modern than that of the Claiborne sands ; and as both deposits hae but 

 two species in common, I thought it advisable to designate the former, Upper 

 or Newer Eocene, and the latter Lower or Older Eocene, as the two divisions 

 are more distinct than the Older and Newer Pliocenes. 



In the American Journal of Science and Arts, I have given a sketch of the 



* Reports on the Icthyology and Herpetology of Massachusetts, by D. Hum- 

 phreys Storer, M. D., p. 230. 



