INSTITUTE OF SCIENCE, PHILADELPHIA. 4I3 



T. siibcouiciim, T. carinatum, 7. lenticulare and T. mnbilicahim of H. C. Lea, 

 and the following species : 



Teinostoma milium n. s. 



Chesapeake Miocene of Wilmington, N. C, Burns; Pliocene of the 

 Caloosahatchie and Shell Creek, Dalland Willcox. 



Shell minute, polished, smooth, depressed-conic, with three whorls ; 

 suture simple, not impressed; periphery evenly rounded, base moderately 

 rounded, umbilicus open in the young, boundedby an obscurely angular ridge 

 terminating at the pillar, in the adult filled with callus, the surface of which is 

 somewhat concave; aperture nearly rounded, somewhat concavely flexuous 

 at the periphery and produced above and below; margin somewhat oblique. 

 Max. diam. 1.5 : alt. 0.8 mm. 



This little shell is well represented by the figure of T. iiiargaritida 

 Deshayes (An. s. Vert. Bas. Paris, 3, pi. 63, figures 9-11), except that it is 

 slightly more depressed, the aperture more concave at the periphery and the 

 umbilical callus less prominent. The spire reveals the whorls distinctly. 



Teinostoma oaloosaense n. s. 

 Plate 23, figure 8. 



Pliocene of the Caloosahatchie River, Florida, Dall. 



Shell minute, polished, smooth; spire depressed, dome-shaped ; whorls 

 three, not differentiated in the profile; periphery rounded; base moderately 

 rounded, the umbilical depression filled smoothly up to the general level by a 

 smooth callus; aperture quite oblique, rounded below, pointed at the upper 

 commissure, the body with a light coat of callus. Max. diam. 2.0 ; alt. I.o mm. 



This species has the edge of the whorls so smoothly thinned out that the 

 profile of the spire forms an unbroken arch or segment of a circle. It is larger 

 than T. iniliuvi and has a different aperture. 



Teinostoma chipolanum n. .s. 

 Plate 23, figures 6, 7. 

 Older Miocene of the Chipola beds, Calhoun County, Florida, Burns, 

 Shell small, tumid, somewhat neritiform, three-whorled ; surface polished 

 with microscopic revolving stride ; dome of the spire slightly gibbous ; a little 

 flattened between the suture and the periphery; base flattish, the spiral striae 

 stronger below ; aperture small, nearly circular, somewhat pointed at the 

 upper commissure ; umbilicus solidly filled with smooth callus, which extends 

 across the body to the outer lip ; inner lip at certain stages of growth 

 separated from the callus by a small groove, at other times the surface is 

 continuous and smooth. Alt. I.o; max. diam. of base 2.3 ; min. diam. 1.8 mm. 

 This curious little shell is well distinguished by its gibbous form. The 

 spirals are only visible in a good light and on a perfectly unworn specimen. 



