250 [March, 1843. 



DONATIONS TO LIBRARY. 



A Flora of North America. By John Torrey and Asa 

 Gray. Yol. 2, Part III. New York and London, 1843. 



VERBAL COMMUNICATIONS. 



Professor Rogers remarked, in reference to the fossil 

 specimen presented this evening by his brother, that no 

 recent contribution to our Palseontology was more inter- 

 esting at this time than the discovery, by the latter, of this 

 familiar European species, in a particular division of the 

 New Red Sandstone of Virginia. Being an abundant and 

 characteristic shell of the Upper New Red Sandstone of 

 Europe, its occurrence in this country is regarded by Prof. 

 W. B. Rogers as affording the first decisive indication of 

 the precise date or equivalency of the extensive American 

 formation already referred by Prof. Hitchcock, by himself 

 and other Geologists, to the general Poikilitic or New Red 

 Sandstone period. 



