38 LAND AND FRESH-WATER SHELLS OF N. A. [pART IV. 



whorl, -niiich may be more distinct on the superior whorls when 

 found perfect. The aperture is about half the length of the shell. 

 — Lea. 



The following is Mr. Lea's description of 



Lithasia solida. — Shell smooth, elliptical, rather thick, j'ellowish- 

 brown; spire somewhat drawn out; sutures impressed; whorls flat- 

 tened ; columella incurved, thickened above and below ; aperture 

 elongated, elliptical, white. 



Habitat. — Alabama. 



Diameter, -38; length, -00 of an inch. 



Observations. — Three specimens only were sent to me by Dr. 

 Foreman. They difler very little from each other, except that one 

 exhibits a few indistinct, elevated, revolving stria?. Other speci- 

 mens may present this character more strongly. Neither of the 

 specimens has a perfect spire, the apices being eroded. The number 

 of whorls I should think, however, were five. The aperture seems to 

 be rather more than half the length of the shell. The columella is 

 remarkable for its callus near the base as well as having another 

 above. — Lea. 



Until the possession of more specimens will enable nat- 

 uralists to distinguish L. hrevis and L. solida, they had 

 probably better remain united as one species. Reeve's figure 

 of the latter appears to have too long a spire, and to be dif- 

 ferently formed in the aperture. 



Mr. Reeve has not recognized the genus Lithasia, and accord- 

 ingly changes the name to trivittata, Reeve, because Mr. Lea 

 had already used hrevis for a Melanian. 



12. L. fusiformis, Lea. 



Lithasia fiisif or mis. Lea, Proc. Aoart. Nat. Sci., p. 51, 1861. Jour. Acail. Nat. Sci., 

 V, pt.3, p. 2(n, t. 35, f. 7L Obs., ix, p. 71. 



Description. — Shell sulcate, fusiform, rather thin, obscurely fur- 

 rowed, reddish-brown, four-banded, conical; sutures irregularly im- 

 pressed; whorls six, the last large and somewhat inflated; 

 Fi.?. 83. * 



aperture elongately rhomboidal ; whitish within and four- 



,„,., banded, channelled and recurved at the base; columella with 

 double curve, thickened above ; outer lip somewhat con- 

 stricted, with an acute margin. 

 Oj)erculum small, ovate^dark brown, serrate around the base and 



