﻿AMERICAN TERTIARY AND CRETACEOUS FOSSILS. 383 



lines on the upper whorls and near the base of the body whorl, which are crossed by 

 equally delicate longitudinal lines, giving the first three whorls a finely cancellated 

 appearance. 



Dimensions. — Length about 1 in., width of body whorl # 4 in. 



Locality. — Wheelock, Texas. Collection of the Smithsonian Institution. 



MITRA, Lam. 



M. Mooreana. PI. 67, fig. 24. Shell subfusiform, whorls eight, apex mamillated, 

 suture distinct ; mouth about half the length of the shell, outer lip sharp, plain, inner 

 lip heavy, four large folds on the columella ; surface marked by short spinous nodes 

 on the angle of the whorls (about eight on the body whorl), and by numerous fine 

 revolving lines, crossed by prominent lines of growth. 



Dimensions. — Length 1*05 in., length of mouth "6 in., width of body whorl, in 

 eluding spines, "5 in. 



Locality. — Wheelock and Caldwell County, Texas. The figure was accidentally 

 reversed. 



M. exile. PL 67, fig. 23. Shell subfusiform, whorls eight, the first three smooth 

 and polished, the remainder truncated above ; suture deep ; mouth small, linear, outer 

 lip simple, four folds on the columella; surface, except the first three whorls, marked 

 on the upper edge, immediately below the suture, by a broad, slightly undulating 

 band, and by prominent longitudinal ribs, which form almost continuous lines from 

 the top of the fourth whorl to near the base 'of the body whorl, body whorl marked 

 at the base by a few transverse lines, continuation of the folds on the columella. 



Dimensions. — Length '25 in., length of mouth - 09 in., width of body whorl "08 in. 



Common. 



ERATO, Risso. 



"^ E. semenoides. PI. 67, fig. 49. Ovoid, whorls about three, spire very low; mouth 

 linear, narrow, inner lip with a number of large teeth ; outer lip very much inverted 

 so as to resemble in an old specimen a nearly perfect Cyprsea, finely crenulated inside, 

 anterior emargination deep. 



Dimensions. — Length -15 in., greatest width "09 in. 



Resembles closely E. semen, (Marginelld semen, Lea,) but can be distinguished, by 

 its size, being not as large by one-third. 



Locality. — Caldwell Co., and Wheelock, Texas. 



This species has never been found at Clairborne, nor has E. semen yet been seen 

 from the Texan strata. 



