OF THE UNITED STATES. 379 



penultimate volution ; umbilicus rather small, pro- 

 found. 



Longth less than one-tenth of an inch. 



Inhabits Pennsylvania. 



This very small species is found in plenty in the 

 fish ponds at Harrowgate, crawling on the dead leaves 

 which have fallen to the bottom of the water. It re- 

 sembles P. lustrica, but is a smaller, less elongated 

 shell, and the superior portion of the labium is not an 

 unaltered continuation of the lips as in that shell, but 

 is appressed to the surface of the penultimate whorl 

 in the usual manner of calcareous deposition upon 

 that part. 



MELANIA. 



1. M. *catenaria. Shell conic, blackish ; whorls 

 seven or eight, slightly undulated transversely, and 

 with eight or nine revolving, elevated lines, the four 

 or five superior ones of which are almost interrupted 

 between the undulations. 



Length less than half an inch. 



Inhabits South Carolina. 



The essential specific character resides in the cate- 

 nated appearance of the superior revolving lines of the 

 whorls, resulting from their being more prominent on 

 the undulations which they cross, than between them, 

 where they are often obsolete. This species was 

 sent to me by Mr. Stephen Elliott, who obtained it 

 in limestone springs, St. John's, Berkley. 



