S6 Coprolites. 



tained that the groove for the nerve does not exist in all the 

 species which may be discovered, it will only be requisite to 

 strike out the words "•' a groove on,'''' to make the generic charac- 

 ters as originally established on a single fragment of jaw, ap- 

 ply correctly to all. 



In the present state of our investigations the following are 

 the specific characters which distinguish the species already as- 

 certained : 



S. lanciformis. Projecting portions of the teeth smooth and 

 obtusely lanciform. 



S. Leanus. Teeth rather acute, slender, slightly compressed 

 and aduncate. 



Coprolites. 



These curious organic fossils, so classically described by Dr 

 Buckland, and which occurred so plentifully in the Lias of 

 England, are occasionally met with in the New Jersey se- 

 condary. 



A specimen of the Saurocopros genus is described and figured 

 by Dr Dekay, Ann. of the Lye. Nat. Hist. N. York, vol. iii. 

 p. 140, pi. iii. fig. 6. 



We have only further to observe concerning the fossil Sauria 

 of the United States, that we possess a curious fossil tooth from 

 South Carolina, presented by Dr S. Blanding, whose root dis- 

 plays a mode of articulation peculiarly its own, and which may 

 be hereafter found to indicate the type of a new fossil genus 

 of animals ; the same may be inferred from numerous fossil ver- 

 tebrae from the New Jersey secondary formations in my pos- 

 session, which differ in their structure from any others hitherto 

 described. We have seen in possession of Mr Dekay, the in- 

 ferior jaw-bone of a nondescript fossil animal found in New 

 Jersey, which bears some analogy with a jaw-bone figured 

 in Mr IMantell's " Geology of the South East of England," 

 p. 153, under the name of " Jaw of a Reptile." My friend Dr 

 Pickering refers this fossil to the jaw of a fish of the genus 

 Sphyr.«na, B1. * 



CLASS PISCES. 



ICHTHYOLITES. 



The fossil remains of fish are by no means of rare occurrence 



• Dr Agassiz has referred the specimen of " Jaw of a Reptile'" in Mr 

 ^Mantell's collection, to the class Pisces. — Ed. 



