141 



Shell oblong-conic, tapering, more or less tinged with rufous ; 

 whirls eight or ten, without much convexity, with elevated, 

 numerous revolving lines, about fifteen on the body whirl and 

 live on those of the spire ; suture of the spire impressed, often 

 indistinct ; of the body whirl very deeply indented ; apex with a 

 small truncation ; labrum near the base not remarkably pro- 

 duced ; base without any rudiment of a sinus ; body whirl slightly 

 ventricose. 



Length, one inch and one-fourth. Greatest breadth, eleven- 

 twentieths. 



It was sent to me from Mexico by Mr. Wm. Maclure. It may 

 be distinguished from multilineata, Say, by its superior magnitude, 

 greater elevation of the striae, less prominence of the labrum near 

 the base, &c. 



Melania ntjpera. — Oblong-oval; volutions five, slightly 

 rounded ; body whirl with about three revolving series of subequal, 

 equidistant, subacute granules or tubercles not higher than wide, 

 occupying the superior half of the surface ; second volution with 

 but two series, remaining volutions with slightly elevated, longi- 

 tudinal lines, instead of tubercles ; but these are often obsolete ; 

 spire towards the tip decorticated ; suture not deeply impressed ; 

 aperture longer than the spire ; sinus of the superior angle pro- 

 found ; labrum concave, with a callus near the superior angle ; 

 columella with a slight, obtuse, hardly prominent angle above the 

 sinus, which is obvious ; labrum not abbreviated above, nor much 

 produced near the base. 



Length, four-fifths ; breadth, less than half an inch. Inhabits 

 the Wabash River. Var. a. Body whirl with but one series of 

 of tubercles. Var. h. Body whirl with four or more series of 

 tubercles. 



This species is common in the Wabash River. The spire is 

 almost invariably so completely decorticated towards the apex, 

 that no trace of the longitudinal lines remains ; in the young 

 only are these lines distinct, and even in these they are frequently 

 wanting. 



Melania cancellata. — Shell rather slender, attenuated ] 

 volutions convex, with about twenty-six reclivate, longitudinal, 

 elevated lines, crossed by about eighteen revolving ones, the eight 

 or nine towards the base crowded. 



