7 
The ground colour of the shell is white, tending toward pale greyish 
vinaceous, with specks and mottlings of cacao brown and brownish vin- 
aceous, the whole merging to sorghum brown on the apex. There are 
weak traces of three major brownish -vinaceous bands, and several basal 
minor ones, the uppermost of the former being traceable well up the 
spire. 
The embryonic shell is sculptured by weak radial wrinkles, which 
gradually develop into a. fine, rather irregular ribbing, but any spiral 
sculpture originally present is eroded to the merest trace in the specimen 
seen. 
Measurements. Maximum diameter of type, 19-1; minimum diameter, 
16-2; altitude, 11*5; diameter of umbilicus, 3*5 mm.; number of 
whorls, 5^. 
Type: Victoria Memorial Museum Collection, Cat. No. 2882. 
Type Locality : Columbia River valley, west of Rocky mountains, Donald 
Station, B. C.; (J. B. Tyrrell, Sept. 21, 1883?); 1 specimen. 
Remarks. This demure mountain snail is of plain appearance, offers no 
very striking peculiarities, and yet seems incapable of reference to any of 
the races or subspecies heretofore recognized. The shell characters seem 
about as conclusive as such things can be in Oreohelix, that it belongs to 
the typical group of 0. strigosa , and here possibly closer to Hemphill’s 
parma from northern Washington than to anything else. From the latter 
it is readily distinguishable, however, by its much narrower umbilicus and 
smaller size. 
In any event the shell is of interest as carrying the stngnsa-group of 
Oreohelix north of the United States border for the first time. The typical 
strigosa is said to come from the “Interior of Oregon”, but its various sub- 
species extend south through Idaho, Utah, and Colorado, to Arizona and 
New Mexico. It is very doubtful whether the 0. alpina of Elrod, from 
the Mission range, Montana, belongs in the same species-series. In fact 
specimens neither of the true strigosa nor of any of its subspecies seem yet 
to have been discovered in Montana. They have been so reported several 
times, but seem generally referable to some form of cooperi. 
Definite record in the matter seems to be lost, but there is reason to 
believe that the unique specimen of canadica was collected by J. B. Tyrrell, 
who visited Donald, September 21, 1883. 
Gonyodiscus cronkhitei (Newcomb 1865) 
1865. Helix cronkhitei Newcomb, — Proc. Cal. Acad. Nat. Sci., vol. 3, p. 
180. 
1866. Patula cronkheitei Tyron, — Am. Jour. Conch., vol. 2, p. 263. 
1885. Patula striatella (pars) Binney, — Man. Am. Landsh., p. 70, f. 30. 
1893. Patula striatella Taylor, — Nautilus, vol. 7, pp. 86 (recorded from 
Laggan, Alberta). 
1895. Patula striatella Taylor, — Ottawa Nat., vol. 9, pp. 176, 177 (recorded 
from Macleod and Little Bow river, Alberta). 
1898. Pyramidula striatella (pars) and P. striatella cronkhitei Pilsbry, — 
Nautilus, vol. 11, p. 141. 
