19-i 



the preceding, by its greater proportionate length, more acute spire, 

 and by the revolving lines of the body volution. I have seea but a 

 single example of the species. 



Red River, Lamar County, in marly clay group. 



Dr. G. G. Shumard collector. 



Genus Solidula, Fischer. 



S. RiDDELLi, (n. sp.) Shell small, moderately thick, elongate- 

 ovate ; length about double the height ; spire short, composed of 

 convex whorls (number unknown) ; spiral angle convex ; last volu- 

 tion widest about the middle, narrowly rounded at the inferior ex- 

 tremity ; suture deeply impressed, linear ; aperture narrow, elongate, 

 terminating above in a sharp angle ; surface elegantly marked with 

 fine lines of growth, and numerous, distinctly impressed, revolving, 

 punctate strije, alternating with finer and shallower ones. The striae 

 are not so wide as the intervals between, and on the body volution 

 they amount to nine or ten in number. 



Length, 0.48 inch ; width, 0.23. 



This species may be compared with S. attenuaia of Meek and 

 Hayden, but is proportionally wider and the revolving strise are 

 coarser. 



Found in the Ripley Group, Navarro County. This species is dedi- 

 cated to Dr. W. P. Riddell, of the Texas Geological Survey. 



Genus Tornatella, Lamarck. 



T. Texana, (n. sp.) Shell small, thin, ovate, somewhat polished ; 

 spire short, enlarging rapidly from apex, spiral angle 78° ; volutions 

 four and a half or five, rounded ; last one large, ventricose ; suture 

 sharply impressed, linear ; aperture narrow, subovate, strongly 

 rounded below and narrow above, about as long again as wide, and a 

 little longer than the width of the shell ; outer lip sharp ; columellar 

 lip with a notch near the middle, and a distinct, twisted, oblique fold 

 just below ; surface marked with very fine strise of growth, crossed 

 with fine, sharply impressed revolving punctate striae, close together 

 on the upper and lower portions of the body volution, and separated 

 by wide equidistant spaces on the middle. The striae of growth are 

 most prominent on the upper part of the body volution. 



Length, 0.28 inch; width, 0.15 ; length of aperture, 0.17. 



Lower Cretaceous, Red River, Lamar County. 



Dr. G. G. Shumard collector. 



Genus Cyhchna, Loven. 



. C. 8TRIATELLA, (n. sp.) Shell elongate-ovate, rounded at apex, 

 nearly elhptical, length almost double the width ; spire umbilicate ; 

 aperture narrow, arched, with subparallel sides above the middle and 

 gradually enlarging below to near the base, where it is again slightly 



