GEOLOGICAL SOCIETY. 



95 



CLASS CRUSTACEA. 



ORDER DECAPODA. Cuv. 



Genus Cancer. Linn. 



The Atlantic secondary formation, particularly of 

 New Jersey, is the richest locality for these kind of 

 fossils. 



Dr. Van Rensselaer has described and figured several 

 specimens of cancer from the above named locality, in 

 the Ann. of the Lyc. Nat. Hist, of N. York, vol. i. p. 

 195, pi. xiv. The cabinet of the Lyceum, and of the 

 Academy of Natural Sciences of Philadelphia, contain 

 various specimens. In most cases they are said to bear 

 considerable analogy with the genus Pa gurus, of modern 

 authors. 



Locality. New Jersey, Chesapeake and Delaware 

 canal &c. 



Place in the Geological series. Cretaceous group. 

 u Ferruginous conglomerate sand" of New Jersey, 

 which Dr. V. refers to the tertiary, others to the se- 

 condary formations of the Atlantic. 



In the cabinet of the Academy of Natural Sciences, 

 Philadelphia, there is a fossil specimen of the genus 

 Astacus, from the deep cut of the Chesapeake and Dela- 

 ware canal ; and also, a slab of carboniferous limestone 

 filled with impressions of a crustaceous animal, about the 

 size of a pea ; the specimen is labelled " Cancer. 



