Ill 



This very small species is found in plenty in the fish ponds at 

 Harrowgate, crawling on the dead leaves which have fallen to tlio 

 bottom of the water. It resembles 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 ap- 

 pressed to the surface of the penultimate whorl in the usual manner 

 of calcareous deposition upon that part. 



Melania catenaria. — Shell conic, blackish ; whorls seven or 

 eight, slightly undulated transversely, and with eight or nine re- 

 volving, 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 catenated appear- 

 ance 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 lime- 

 stone springs, St. John's, Berkley. 



Melania multilineata. — Shell gradually tapering; apex 

 generally much eroded ; whorls about seven, a little convex, with 

 numerous, filiform, elevated, subequal lines, which are from ten to 

 twenty in number on the body whorl. 



Length nineteen-twentieths ; greatest width two-fifths of an 

 inch. Inhabits tributaries to the Delaware. 



I found several specimens of this shell in Frankford Creek j and 

 Professor Vanuxem presented me with others which he obtained 

 from a creek in New Jersey. The M. elevata, (p. 176 of this 

 work,) from its attributed specific characters, might be supposed 

 to be nearly related to this shell, but it difi"ers in being of a more 

 accurate conic form, the whorls being flattened, and not convex as 

 in this species ; its raised lines are also few in number. 



Cyclas rhomboidea. — Shell transversely orbicular-rhombi- 

 form, subequilateral, pale, with elevated somewhat regular trans- 

 verse lines ; umbo not prominent. 



Breadth more than one-fourth of an inch. Inhabits lake Cham- 

 plain. 



It is probable that this species attains to a somewhat larger size 

 than the two specimens from which the above description was 



