320 LAND AND FRESH-AVATER SHELLS OF N. A. [PART IV. 



striate ou its upper lialf; sutures impressed; aperture rather large, 

 ovate, whiUsh, inclining to roseate. 

 Habitat. — Georgia. 



Diameter, -40 (10 millim.); length, -88 of an inch (23 milim.). 

 Fig. 617. Length of aperture, -39 (10 millim.) ; breadth of aper- 

 ture, -20 of an inch (5 millim.). 



Observations. — In form like 31. Duttoniana, Lea, but 

 without any of the ornamental decorations of tliat spe- 

 cies. The nodules are not so distinct, appearing more 

 like interrupted folds. The striae on the body-whorl are 

 not uniformly distributed, but above the middle there is 

 a plain surface or ground, ■\vhich becomes more decidedly a furrow on 

 the penultimate whorl. — Anthony. 



G. Jiarpa is narrower than laeta with tlie mouth more acumi- 

 nate below. The striiB are smaller and closer. 



229. G. oliva. Lea. 



Melaniaoliva, Lea, Philos. Proc, ii, p. 242, 1842. Philos. Trans., ix, p. 27. Obs., 

 iv, p. 127. Wheatley, Cat. Shells U. S., p. 26. Binney, Check List, No. 

 187. Brot, List, p. 33. 



Megara oiiva, Lea, Adams, Genera, i, p. 306. 



Description. — Shell striate, elliptical, solid, brown; spire rather 

 short ; sutures much impressed ; whorls convex ; columella incurved, 

 thickened above ; aperture ovate, white. 



JIahitat. — Alabama. 



Diameter, -50 of an inch ; length, 1 inch. 



Observations. — This is a ponderous and rather large species, with 

 not very distinct striaj on the few specimens before me. The supe- 

 rior part of the columella is quite callous. The apex of each is too 

 much eroded to designate the number of the whorls. The aperture is 

 rather small and contracted. One of the specimens is rather coarsely 

 plicate. — Lea. 



This shell is narrower than laeta, resembling liarpa in form, 

 but with the aperture wider and more rounded below. It is 

 very closely allied to G. excavata, which is a smooth species, 

 liowever. 



