li 
— 
1910.] NATURAL SCIENCES OF PHILADELPHIA. 79 
Cave Creek (cataracta). The lower line is a similar but independent 
chain from the southern canyons, a considerable distance from the 
nearest of the more northern group. 
From Big Emigrant Canyon to Shake Gulch the Stations mentioned 
above run in a general direction from northwest to southeast. From 
the emigrans station to Onion Creek station is about 16 miles; 
thence to Cave Creek, 4; to Cave Creek Falls (var. cataracta), 2; to 
Rucker Box, 12; to Shake Gulch, 12. Total, 44 miles as the crow 
flies ; but it is 55 by trail. 
One peculiarity runs throughout the entire clappi series: they are 
hard to catch. Except at Onion Creek they were grouped in small 
families and the families did not seem to be upon speaking terms. 
They were clannish and confined their travels to one particular rock 
slide. In only two instances was the same form found in two slides of 
rock, though the rocks were well explored for miles around. At Onion 
Creek they were plentiful; about 100 were collected there in an hour. 
Oreohelix clappi emigrans n. subsp. 
This shell is similar in outline to O. clappi, but more sharply angular 
at the periphery, or even carinate in front. Cuticle thicker, rough, 
usually persistent, dark olive brown in color, lusterless, not banded, 
coated and caked with a deposit of humus. The sculpture after the 
embryonic shell consists of oblique, uneven, rather sharp striw, and 
Fig. 7.—Oreohelix clappi emigrans. 
on the last whorl some coarse wrinkles. The stri# are sharper than 
in O. clappi and close together up to the last whorl; on the base they 
are thread-like, crimped and waved at the intersections of four or five 
circular rows of short cuticular appendages, which are usually retained 
only on the latter part of the base. In immature shells the thread- 
like striae are surmounted by delicate cuticular lamin, more or less 
felted together by the adhering dirt. The aperture is rounded- 
