18 [Mat, 1841. 



Description of the Insects brought home by Commander James 

 Clarke Ross, R. N. By John Curtis, Esq., F. L. S. 4to. 

 From the Author. 



Written Communications. A communication was read 

 from Dr. A. Clapp, of New Albany, Indiana, in reference to 

 the Geological equivalents of that vicinity, as compared by him 

 with those described in the Silurian System of Murchison. 



" The following fossils, which characterize the Wenlock Lime- 

 stone of Murchison, I have found in the Limestone of the Falls of 

 the Ohio: Favosites spongites, Retepora prisca. Acervularia 

 Baltica, Astrea ananas? Cyathophyllum turbinatum, Syringipora 

 reticulata, Calymene bufo. 



"I have also observed, at the same place, the following group 

 of Wenlock fossils, which, however, are not characteristic of the 

 Limestone of the Falls : Catenipora escharoides, Syringipora 

 bifurcata, Stomatapora concentrica, Favosites C4othlandica, 

 Turbinalapsis bina, Strophomena euglypha? Atrypa prisca. 

 To Avhich I may add the following fossils of Goldfuss, which are 

 not found in the Wenlock Limestone, and some of them not even 

 in Wales: Cyathophyllum ceratites, C. vermiculare, and C. 

 helianthoides, Stomatopora polymorpha, Favosites polymorpha, 

 and F. basallica, Gorgonia infundibuliformis? the last being more 

 common in the latter formations. (Ludlow.) Besides the preced- 

 ing species, I have many Polyparia, and some shells of the Falls 

 Limestone yet undetermined. In the Limestone and Marls of 

 Madison and Hanover, in Indiana, I have identified two other 

 species belonging to the Wenlock shale, viz.: Terebratula 

 spherica? and Orthocera eccentrics. 



The middle and lower strata of the Blue Limestone and Marls 

 at Cincinnati, and the lowest at Madison and Hanover, appear to 

 be equivalents of the Caradoc Group of Murchison, and contain 

 the following fossils: Orthis callactis, Calymene punctata, C. 

 Blumenbachii, Triarthus Beckii, Isotelus , Pentacrinit.es prisca, 

 (Goldf.) This formation has very few Polyparia, but many 

 shells, which are different from any described by Goldfuss or 

 Murchison. 



" The black bituminous slate that overlies the limestone at the 



