ANGITREMA. 23 



(Say), but is smaller and much less ponderous. The tubercles are 

 more numerous and less elevated. 



In the tuhercuJata the impressed band, ■which exists in the armigera 

 above the armature, is wanting. In color it differs altogether. — Lea' 



In Phil. Trans., vi, p. 82, Mr. Lea changed the name of his 

 species, as the original name was preoccupied by Spix. He 

 therefore proposed, instead of tuherculata, the name S2yixiana. 

 Mr. Reeve, finding tuberculata preoccupied by Spix, and not hav- 

 ing seen Mr. Lea's change of name, proposed nodata. These 

 names must all yield, however, to Say's styrjia, which is the 

 first published description of the species. Mr. Say himself 

 (cover of Conchology, No. 6) decided Mr. Lea's species to be 

 a S3'non3'me — an opinion in which he has been sustained by 

 several of our conchologists. 



Through the kindness of Mr. Lea I have been permitted to 

 examine a number of specimens in his cabinet. They exhibit 

 every gradation, from a smooth to a tuberculate surface. 



D. Bochj-whorl toith numerous tubercles, in parallel roics. 

 11. A. lima, Conkad. 



Melaiiia lima, Coxrad, New Fresh-Water Shells, p. 54, t. 8, f. 8, 1834. CiiExn, Re- 

 print. DeKay, Moll. N. Y., p. 97. Wheatley, Cat. Shells U. S., p. 2(i. Jay, 

 Cat., 4th edit., p. 274. Catlow, Couch. Nomenc, p. 187. Bkot, List, p. 33. 

 MfLLEU, Synopsis, p. 4G. 



Anculotus lima, Conrad, Reeve, Monog. Anc, t. 1, f. 1. 



Lithasia lima, Conrad, Bixnev. Check List< No. 300. 



Megara lima, Conrad, Adams, Genera, i, 30G. 



Description. — Shell conic, or subfusiform ; with approximate nodu- 

 lous, spiral lines of unequal size ; body-whorl angulated ; j,- gg 

 angle with a series of prominent tubercles ; base with 

 two lines, the superior one nodulous ; aperture nearly 

 half the length of the shell, contracted, and acutely an- 

 gular above, and obtusely pointed at base ; labrum very 

 thin; color olive; within with purple bands. 



Observations. — A fine species, easily recognized by its 

 numerous tubercles, and ventricose form. Inhabits Elk 

 River, Alabama, adhering to stones, and is a common species. — Conrad. 



Distinguished from L. verrticosa, Kaf. {nvpera, Sa}'), by its 



