LYELL ON THE CRETACEOUS STRATA OF NEW JERSEY. 59 



lata, Gastrochcena, and Teredo, the whole indicating the sandy 

 bottom of a shallow sea. I was so strongly reminded of the 

 coralline crag of Sudbourn, and other places in Suffolk, when 

 examining this rock, that I had some difficulty at first in per- 

 suading myself that it was not a tertiary deposit. It is, in a great 

 part, a mass of white calcareous sand, more or less aggregated 

 together, and the upper surface has been irregularly scooped out 

 and rendered undulating, and is covered with a newer deposit of 

 red clay and gravel, without fossils, the surface of which is even 

 and level. This white sand and limestone pass downwards into 

 light-green and ferruginous sand, with quartzose grains. 



Near Hornerstown, I saw, on a branch of the Timber Creek, to 

 which Mr. Conrad conducted me, a bed of this coralline aggregate, 

 8 feet thick, resting on the green sand or lower deposit before 

 mentioned, with its characteristic fossils. 



We have now to consider whether the calcareous or upper 

 formation has been referred with propriety to the chalk. Mr. 

 Forbes has examined the Echinoderms, and is of opinion that they 

 are decidedly analogous to cretaceous forms. One of the species 

 of Spatangus belongs to the same group as S. subglobosus of 

 Goldfuss, a group which forms the genus Holaster of Agassiz, and 

 which that naturalist regards as very characteristic of the upper 

 part of the Cretaceous system. 



One also of two species of Cidaris is allied to C. vesiculosus, and 

 to other upper cretaceous species of Europe. 



Dr. Morton had already observed, in regard to the corals, that 

 some of the species resemble a Maestricht fossil, figured by Gold- 

 fuss ; and the reader is referred to Mr. Lonsdale's comments on 

 this subject in the Appendix. 



The fossil called by Dr. Morton " Belemnites ambiguus" though 

 probably not related to the Belemnite, is ' closely allied to a fossil 

 which I have collected myself in the chalk of Sweden, associated 

 with Belemnites mucronatus. 



The last-mentioned, or upper of the two fossiliferous formations 

 of New Jersey, has been called by Dr. Morton and Mr. Conrad the 

 Medial Cretaceous, because there are others still higher in position 

 in the Southern States, which they refer to the chalk period. One 

 member of these, a white limestone, seen extensively on the Santee 

 canal, and in other parts of South Carolina, as well as at Jackson- 

 borough and Shell Bluff in Georgia, I have shown, in a former 

 communication to the Society, to be Eocene tertiary. Another 

 portion, called the Nummulite limestone of Alabama, I have not 

 examined, and can therefore offer no opinion respecting it. 



Upon the whole, the collection of fossils which I made in New 

 Jersey confirms the principal conclusion to which Dr. Morton 

 arrived, that there is a remarkable generic accordance between the 

 fossil mollusca, corals, echinoderms, fish, and saurians of the cre- 

 taceous group, in New Jersey and in Europe. But the general 

 analogy of the generic, and the identity of some specific, forms, 

 which Mr. Forbes and Mr. Lonsdale have assisted me in comparing, 



