50 THE NAUTILUS. 
Type Locality: 7,550 feet altitude, cienaga near Bluff Lake, 
San Bernardino Mountains, California; under sticks and logs at 
edge of forest; Nina G. Spaulding, G. E. Dole and S. 8. Berry, 
August, 1910; 59 specimens in this and neighboring cienagas. 
Also taken at 7,200 feet altitude, west slope of Falls Creek 
Canyon, near the narrows about one mile above Dobbs Cabin, 
Dollar Pass Trail, San Bernardino Mountains, California; under 
small sticks and pine cones on springy slope; G. HE. Dole and 
S. S. Berry, Sept. 29, 1918; 32 specimens. 
Remarks: This very puzzling little mollusk is one of the most 
beautiful of American Vertigos. It is very close to V. modesta 
parietalis and may also be described as an albinistic race of that 
subspecies, but it is a protean form and some shells are equally 
close to V. modesta modesta or even to V. m. castanea. That it 
is more than amere ‘‘albino’’ of the recognized type is strongly 
evidenced by its occurrence in such abundance and at scattered 
localities, as also by the fact that its distribution is by no means 
coincident with that of any of the other forms mentioned. 
Nor, although usually associated, do the white or brown shells 
occur in any apparent regular ratio. At the second locality 
above cited diligent outlook yielded but three specimens of the 
brown parietalis. It is evidently a comparatively recent offshoot 
from the parent stock, but the field evidence is that it already 
is a race with its peculiar characters heritable to a marked 
degree. 
It seems rather remarkable that such features as the color, 
shell texture, and similar characters in this form should exhibit 
such constancy as compared with the variability shown in the 
development of the lamellae. In 39 specimens of the type lot 
now before me, 1 has only 2 teeth (columellar and parietal), 
15 have 3 teeth (columellar, parietal, and lower palatal), 9 
have 4 teeth (an upper palatal usually the one added), and 14 
have a full set of 5 teeth. No mature specimens with fewer 
than 2 nor more than 5 teeth have been noted. This variation 
in a single well-defined colony (its members having, as shown 
by the other characters noted, an undoubtedly close phylo- 
genetic relationship with one another) throws a valuable bit of 
light on the difficulty of attempting the separation of the var- 
