96 NEW-YORK FAUNA — MOLLUSCA. 



M. congesta. (Id. Am. Jour. Vol. 2.5, p. 343.) Shell subulate, with about nine volutions, the 

 lower ones obscurely angulated, those of the spire acutely carinate towards the apex: suture 

 well defined ; body-whorl obscurely angulated ; aperture longitudinally elliptical. Alabama. 



M. elwata. (Say, Ac. Sc. Vol. 2, p. 176. M. elongata? Lea, Am. Tr. Vol. 4.) Shell gradually 

 attenuating to the ape.x, slightly and irregularly wrinkled ; suture not deeply impressed. 

 Whorls 9 - 10, with several more or less elevated revolving lines, of which one being more 

 conspicuous, gives the shell a carinated appearance. Aperture oblique, equalling the length 

 of the 2d, 3d and 4th volutions together. Color, olivaceous. Length, I'O; breadth, 0'4. 

 Ohio river. 



M. excurata. (Conrad, Fr. Wat. p. 49, pi. 4, fig. 6.) Shell subulate, with a spiral band of slightly 

 oblique subcompressed tubercles on the base of the inferior whorls : above this, a prominent 

 line with a slight intervening channel. Whorls towards the apex nearly entire : base with 3 

 prominent lines ; the upper ones largest ; the third hardly prominent, and approximating to 

 the middle one. Color : epidermis reddish brown or black. Alabama. 



M.'i integra. (Say, Des. terr. and fl. shells, p. 18.) Subglobose. Whorls 3, rounded, obsoletely 

 wrinkled ; spire very short, less than half the length of the aperture ; suture rather deeply 

 impressed ; body-whoil large ; aperture dilated, ovate, acute above ; columella flattened, 

 polished ; lip regularly rounded ; base rounded, without undulation or sinus ; umbilicus none ; 

 opercle obviously spiral. Length, 0'2. Ohio river. 



M. teres. (Lea, Tr. Am. Phil. Soc. Vol. 8, p. 176. pi. 5, fig. 27.) Shell plicate or folded, acutely 

 turreted, thin : spire drawn out ; sutures impressed ; whorls 9, convex ; aperture small, ellip- 

 tical. Color, horn; white within. Length, 0*87; diameter, 0' 25. Tennessee. 



M. obtusa. (Id. lb. pi. 5, fig. 28.) Shell folded, fusiform, rather thick : spire obtuse ; sutures 

 impressed; whorls 4, the last semiplicate ; aperture large. Length, 0' 55; diameter, 0- 27. 

 Tennessee. 



M. lecontiana. (Id. lb. p. 177, pi. 5, fig. 29.) Shell folded, conical, thick : spire obtusely ele- 

 vated ; sutures small. Whorls 6, flattened ; lower half of body-whorl not folded : aperture 

 large, nearly one-half of total length, elliptical. Length, 0'8; diameter, 0' 35. Georgia. 



M. rugosa. (Id. lb. pi. 5, fig. 30.) Shell folded, conical, rather thin, translucent, transversely 

 striated: spire rather elevated ; sutures much impressed ; whorls seven, convex, cancellated 

 above; aperture rather large, elliptical, angular below. Color, horn. Length, 0'5; diame- 

 ter, 0'22. Tennessee. 



M. mo7iozonalis. (Id. lb. pi. 6, fig. 31.) Shell folded, fusiform, rather thick : spire obtuse ; su- 

 tures linear; whorls 5, rather convex; aperture large, about one-half the total length, ellip- 

 tical. Color, light-colored, with a simple broad band on the upper part. Length, 0- 42; 

 diameter, 0'21. Tennessee. 



M. terebrans. (Id. lb. p. 178, pi. 6, fig. 32.) Shell folded, acutely turreted, rather thin, shining : 

 spire much elevated ; sutures much impressed ; whorls 9, convex, carinate above ; aperture 

 small, about one-fifth of the total length. Color, reddish brown. Length, 0-67; diameter, 

 " 24. Tennessee. 



M. columella. (Id. lb. p. 179, pi. 6, fig. 33.) Shell obscurely folded, conoidal, rather thin: 

 spire rather elevated, striate above ; suture impressed ; whorls six, somewhat compressed ; 



