12 TRANSACTIONS OF THE WAGNER FREE 



Subgenus Polygyra Say. 

 Section Dcsdahchi/a Beck. 

 Helix adamnis n. s. 

 Plate I, figures s, 5 a. 

 Shell small, depressed, five-whorled ; surface nearly smooth except for 

 incremental lines and occasional faint wrinkles • suture distinct as in recent 

 species of this group ; periphery angulated rather obtusely, on which angle 

 the suture runs and at the aperture does not perceptibly decline below it, 

 although the aperture is oblique ; the sides fall inward from the carina ; the 

 base is rounded with a small funicular umbilicus ; at the termination of the 

 last whorl it is slightly swollen, then slightly constricted, then expands again 

 to the subequal thick margin of the aperture, which is marginated rather than 

 reflected ; on the lower lip are two subequal denticles which are not extended 

 into the throat ; about the middle of the outer lip the end of a ridge projects 

 from the margin and the ridge itself is continued obliquely downward and 

 backward on the inside of the outer lip until it reaches a point nearly behind 

 the outer basal denticle. The outer and inner lips are joined over the body 

 by a > -shaped lamina, the upper arm of which is shorter than the lower ; the 

 apex extends backward behind the plane of the lower lip, while the space be- 

 tween the arms of the > is covered with a pretty thick layer of callus. Alt. 

 4.5 ; max. diam. g.i ; min. diam. 7.5 mm. 



A single specimen was collected at Ballast Point by the writer. 



This is the earliest American Polygyra as far as known. A species is 

 mentioned from Idaho (Dakota) in Conrad's "Eocene Checklist," published by 

 the Smithsonian Institution in 1866, but I can find no record of its publication 

 anywhere, and suspect that further study resulted in its suppression. The 

 specimen is not in the National collection and the name is therefore to be 

 suppressed. 



The present species is a full-fledged Polygyra, of the section Dcedalochila 

 Beck, with all the characters which are exhibited in such species as P. ventro- 

 sula and P. Hindsii of Pfeiffer. It is probable, therefore, that the group was 

 developed at an earlier date and that we may yet find incipient or even char- 

 acteristic species of Polygyra in the Eocene. The nearest related recent 

 species, above cited, inhabit Texas, Mexico and the adjacent region. 



Subfamily PUPIN.E. 



Genus STROPHIA Albers. 

 Section Eoslrophia Dal). 



Shell destitute of internal lamellae or denticles. Maynard has shown that 

 the species of Stroplda now living may be separated into three groups by the 

 form and arrangement of the gular laminae or callosities. But according to 

 him there are none known among recent Strophias, which are entirely desti- 

 tute of such laminas, like the Miocene forms now under consideration. 



