271 



was a new comer. Dr. Brewer remarked, that wherever 

 this Swallow makes its appearance, the Barn Swallow gradu- 

 ally disappears, receding before it. He had noticed on the 

 nest of this latter species, on one side, near the top, a shelf 

 of the same materials as the nest, on which one bird sits 

 much of the time, while the other sits on the eggs. As the 

 young increase in size the shelf is occupied by both the 

 parent birds. At night one of these birds is constantly on 

 the watch to prevent surprise. 



The Secretary presented, in behalf of Mr. Temple 

 Prime, a paper on the genus Cyclas, as follows : — 



Notes on the Species of Cyclas found in the United States ; hy 

 Temple Prime. 



Several species I have not as yet been able to identify to my 

 satisfaction. Say's original specimens in the Cabinet of the 

 Acad, of Nat. Sciences of Philadelphia having been destroyed, 

 the' only means left to be sure of his species are to collect them 

 in the original localities. 



The shell known in Massachusetts as C. similis Say, and 

 described and figured as such by Dr. Gould, is found in many 

 different localities through the country ; but never having received 

 it from the Delaware River, where Say found his shell, and hav- 

 ing, moreover, compared it with Say's figure, from which it dif- 

 fers, I am unwilling as yet, without further investigation, to con- 

 sider it definitively as the C. similis Say. 



The C. edentula Say, and Lamarck's three species, I have 

 sought for in their respective localities, but as yet no success has 

 attended my efforts. 



The C. lasmampsis Rafinesque, I hope to have an opportu- 

 nity, before very long, of examining in the Cabinet of C. A. 

 Poulson, Esq. of Philadelphia, in which are deposited all Ra- 

 finesque's original specimens. 



