264 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



tion. Of the 84 Zoophytal appearances, of known matrix, in New 

 York, only twenty- two are in calcareo-argillaceous or argillo-cal- 

 careous shale, this order of creatures frequenting especially the 

 deep seas. Of 155 appearances of Zoophytes in Wales, thirty-five 

 only are in the above-mentioned shales, and thirty-four in non- 

 calcareous habitats. Pive out of seven of the New York Tentaculites 

 are in argillaceous shale, in which also the Annelida of Wales are 

 prevalent. One-fourth of the Brachiopoda of New York are in 

 calcareo-argillaceous or argillo-calcareous shales, and about one- 

 half of those of Wales, — ^the proportion of those in the former coun- 

 try, with the sedimentary relations of which we are acquainted, to 

 those of the latter, being nearly as three to two — a fact due to their 



Table VII. — S]pecies~Life, numerically , as appearing exclusively in 



Calcareous or Non-calcareous habitats in New York and Wales, 



(Reduced from Tables V. and YI.) 



Families and Orders 

 of the Fossils. 



New York. 



Wales. 



Appearances. 



Appearances. 



In 



Calcareous 



Beds. 



In Non- 

 calcareous 

 Beds. 



In 



Calcareous 



Beds. 



In Non- 

 calcareous 

 Beds. 



Plants 



11 

 10 



79 

 51 

 57 

 69 

 27 

 40 

 44 

 93 

 24 

 9 

 95 



23 

 3 



7" 

 5 



24 

 6 



13 

 6 

 2 



8" 



30 

 2 



121 

 59 



169 

 45 



309 

 27 

 57 

 75 

 19 

 17 

 67 

 6 



14 

 19 

 1 

 34 

 23 



154 

 30 



207 

 20 

 69 

 57 

 24 

 13 

 47 

 12 



Annelida 



Amorphozoa 



Zoophyta 



Crinoidea and Cystidea 



Crustacea 



Bryozoa 



Brachiopoda 



Monomyaria 



Dimyaria 



Gasteropoda 



Heteropoda 



Pteropoda 



Cephalopoda 



Pisces 



Total 



823 



102 



1003 



724 





very different extent. The LamellihrancJiiata of New York and 

 Wales are a tolerant race, and inhabit freely the argillaceous shales. 

 The New York Cephalopoda are not so fond of argillaceous strata 

 as are those of Wales. In this last district they are very generally 

 diffused. 



c. Arenaceous strata. — The strata which consist principally of sili- 

 ceous sand are poor in fossils ; but they become richer on the ad- 

 dition of clay or lime. Several marine plants (?) occupy the Middle 

 Silurian sandstones of New York, and in prodigious quantities. Few 

 Bryozoa, Zoophyta, Brachiopoda, &c., and no Crinoids, are seen here 

 in New York. They are more plentiful in the arenaceous strata of 



