348 



PROCEEDINGS OF THE ACADEMY OF 



[May, 



In 0. h. betheli and 0. h. corrugata the central and inner lateral 

 teeth are unicuspid, but there are narrow, cutting edges overhanging 

 from the central cusps, in place of side cusps. 



Oreohelix haydeni mixta n. subsp. 



The shell is whitish with the early whorls clay color (the last whorl 

 sometimes having two narrow brown bands, the upper one ascending 

 the spire). Sculpture often equal, rather fine, deeply cut growth- 

 wrinkles, cut by spiral engraved lines, unequally developed, and 

 on the base often grouped so as to leave spiral bands of long granules 

 at intervals. Periphery angular or subangular in front, becoming 

 rounded on the rest of the last whorl. Embryonic shell having 

 irregular radial ripples, and the usual very fine spiral striation; on 

 the last whorl some coarse spirals ; peripheral carina strongly pinched 

 out. 



Height 18.3, diam. 12 mm.; umbilicus 3.6 mm. 



The genitalia (pi. 21, fig. 3) resemble the organs of 0. haydeni in 

 proportions, the internally ribbed part of the penis being less than 

 half of the total length, but thicker than in haydeni, perhaps an 

 individual feature. The distal part has a somewhat trefoil section. 

 It differs from 0. cooperi by the longer penis relative to the diameter 

 of the shell, its length being about equal to the diameter in this form, 

 but decidedly less in all of the cooperi I have measured. The inter- 

 nally costate part is relatively shorter than in cooperi. 



Glenwood Springs, Colorado, on the bluff above the Hotel Colorado, 

 among oak leaves and debris on a sandstone and shale ledge above 

 station of 0. h. betheli. Type No. 94,058 A. N. S. P. (from No. 447 

 of Prof. Ellsworth Bethel, 1907). 



Another lot from Mr. Bethel, No. 94,796, consists of individuals 

 like the above lot, with others having two narrow spiral lines in the 

 usual cooperi positions. One of this lot (whether banded or plain 

 not known) was dissected, pi. 22, fig. 5. It agrees with the type in 

 proportions of the penis, but the penial retractor and the vagina are 

 shorter. Measurements of the genitalia in mm. follow. 



