274 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



which exists in the recurrent power of orders and genera common 

 to New York and Wales. The group-arrangement employed is that 

 in use previous to the publication of the second edition of Sir 

 E. Murchison's ' Siluria.' 



A very interesting set of recurrents are those which escape from 

 the lower Silurian of New York into the upper, by passing through or 

 beneath the disturbances which, to a certain extent, occurred during 

 the middle stage ; but this subject has been sufficiently treated of 

 in Quart. Journ. Geol. Soc. vol. xiv. p. 450, &c. I shall not prolong 

 my remarks on the recurrent fossils of the Silurian basins of New 

 York and Wales, but shall pass on to a brief consideration of 

 vertical range in the Devonian system of the former. 



Ji. Recurrents of the Devonimi System of New York*. — In treating 

 of this portion of our subject, we meet with several discouragements. 

 The palaeontology of this system in New York has not yet been fully 

 opened to us. Sufficiently acquainted with its mineral characters, 



Table XY. — Exhibiting the great similarity in Recurrent Power of 

 Fossils common to New YorTc and Wales. 



New York. 



Orders and Genera. 



Holopgea, Littorina 



E-aphistoma, Lyrodesma 

 Pln-agmoceras, Turbo .., 



Pterin ea, Orthonota , 



Nucula, Cleidophorus .., 



Lituites, Cyrtoceras , 



Ambonychia, Capulus ... 

 Conularia, Cypricardia.,. 



Euomphalus , 



Pentamerus , 



Annelida, Modiolopsis . , , 

 Bellerophon, Cornulites. 

 Bryozoa, EcMnodermata 



Lingula, Murchisonia 



Orthis, Orthoceras 



Leptaena, Spirifer "1 



Avicula, Trilobites J 



Zoophyta 



Atrypa 



Wales. 



Orders and Genera. 



Holopgea, Littorina 



Raphistoma, Cyrtoceras 



Cypricardia 



Pterinea, Orthonota 



Phragmoceras, Capulus 



Ambonychia, Sanguinolites... 



Conularia 



Modiolopsis, Echinodermata . 



Lingula, Spirifer 



Nucu] a, Mtu-chisonia 



Turbo, Lituites 



Avicula 



Atrypa, Cleidophorus 



Pentamerus, Bellerophon, Eu- 

 omphalus 



Annelida, . Orthoceras 



Zoophyta, Bryozoa 



Leptaena 



Orthis 



Trilobites 



we have much to learn as to its fossils ; but still of these we are in 

 possession of the useful number of 418. Further, there are but 



^ For Table of Devonian Eecurrents, see Q. J. Gr. S. vol. xiv. p. 424. 



