84 PROCEEDINGS OF THE ACADEMY OF [Feb., 



seems closer than usual. Unfortunately, no young examples were 

 taken. 



This form is usually more depressed than that from Onion Creek, 

 with less sharp oblique sculpture. It resembles the remote Onion 

 Creek colony in the lusterless cuticle. Fourteen of about 20 shells 

 taken measure: 



Alt. 9, diam. 15.5 mm. (4 specimens) 



" 9, " 15.7 " 



" 9. " 14.7 " 



" 10, " 14.5 " (senile form). 



" 9.5, " 16.7 " 



" 9, " 14.5 " 



" 10, " 17 



" 9.5. " 17 



" 9.5, " 16.5 " 



" 9.75, " 16 



" 9.5, " 16 



Shake Gulch, where these shells were found, is on the southwest 

 side of the range at about 5,500 feet elevation about 12 miles from the 

 Rucker "box." 19 They live in a rock slide near the stream. 



6. Horse-shoe Canyon Form. — Similar to the preceding except 

 that the peripheral angle is less acute; between the Shake Gulch and 

 Rucker lots in form. Fragments of a long cuticular fringe remain in 

 ■places in the suture from the third whorl to near the aperture, but 

 there are no spiral series of granules or cuticular prominences on the 

 base, thereby differing from O. c. emigrans, and like the forms geo- 

 graphically nearest. Only two collected, both adult, measuring 

 alt. 9, diam. 16 nun. 



Found in Horse-shoe Canyon about ten miles from the mouth, in 

 slide rock, on the opposite side of the main fork from the Red Box, 

 at about 7,000 feet elevation. Both shells taken were freshly dead. 



Oreohelix clappi cataracta n. subsp. 



The shell is depressed, nearly lens-shaped; periphery strongly angular, 

 bright olive green, thin, polished, translucent, occasionally marked 

 with two transparent bands ; 4h whorls, the last wider than in clappi, 

 with the periphery near the flattened top, base strongly convex. 

 Aperture nearly all below the periphery. Parietal callus short, 



19 Shake Gulch is so named from the circumstance that "shakes" (split 

 shingles) are there made from the cypress. 



