94 PROCEEDINGS OF THE ACADEMY OF [March, 
lines and faint traces of microscopic spirals, and on its last third 
there are usually several small spiral threads. The young stages 
have an acutely angular periphery, which becomes bluntly angular 
on the last whorl, which descends very little in front. The aperture 
is strongly oblique. 
Alt. 12, diam. 21 mm. (type). 
i hy ae. Wage 
i 7 ing NV a 
Black Range, at stations 44, 45 and 48, head of Morgan Creek; 
42, Black Canyon, 4 miles below Reed’s ranch; 50 and 51, on Dia- 
mond Creek, about 3 miles below the summit, and again ‘about half 
way down. 
Fig. 3.—Reproductive organs of Oreohelix swopei. b, the penis opened, showing 
fleshy organs in the swollen portion. c, the penis and epiphallus stretched 
straight. 
This snail is named in honor of Dr. 8. D. Swope, of Deming, New 
Mexico, in acknowledgment of his interest in scientific matters and 
his kindly help in furthering our investigation. That we visited 
the Black Range at all was due to his alluring picture of its beauties. 
In the field this shell was taken for O. s. depressa. It was found 
among rocks on the well-shaded slopes of ravines, usually with 
O. coopert and Ashmunella. The absence of spiral striation on the 
last whorl aroused suspicion of the reference to O. s. depressa, and 
on closer study it was found to differ by the far smoother embryonic 
shell, and especially by the soft anatomy, the male organs being 
quite different in the two species. In O. s. depressa the lower part 
\ 
