186 BULLETIN OF THE 
This is a very dark, intermediate form of jidelis, which in its southern march 
under changed conditions assumes a more carinated form, and is known to con- 
chologists as infumata, Gould. 
The above is Mr. Hemphill’s description. 
Arionta Coloradoensis, STEARNS. 
Shell orbicular, moderately depressed, whorls slightly elevated, apex obtuse, 
number of whorls four to four and a half, rounded. Umbilicus narrow, showing the 
penultimate whorl, though partially covered by the reflection of the lip at the point 
of junction with the base of the shell. Aperture obliquely ovate, nearly circular, 
and almost as broad as high. Lip slightly thickened and reflected, or simple, vary- 
ing in this respect; more reflected and aperture more effuse at the columella. 
Parietal wall in the heavier examples calloused, the callus connecting with the 
inner edges of the outer lip above and below. Shell rather fragile, thin, translu- 
cent; surface smooth and shiny, and sculptured with fine incremental lines. Color 
pale horn to white, and otherwise marked by a single narrow revolving reddish 
brown band just above the periphery, which in some specimens is obscure or 
absent. In some individuals certain faint scars upon the upper whorls imply an 
occasionally hirsute character. 
mm. 
Maximum diameter of largest . . . » 2 2 . . + 15.25 
Minimum diameter of largest . . . . 222... 18.25 
Altitude orlargest «e s oora w o a a a o 210.20 
Maximum diameter of smallest adult . . . . . . 18.75 
Minimum diameter of smallest adult . . . . . . 12.00 
Altitude of smallest adult >a 5 sv. par r y Sid 
Grand Cañon of the Colorado, opposite the Kaibab plateau, at an elevation of 
8,500 feet. (Mus. No. 104,100.) 
The above, while exhibiting a facies or aspect of its own, its nevertheless sug- 
gestive of H. Remondi, Gabb, Mazatlan, in the Mexican State of Sinaloa, and also 
from the high'mesas or table lands in the neighborhood of Mulege, Lower Cali- 
fornia. H. Carpenteri, Newcomb, which is a synonym of H. Remondi, is credited 
by the author to “ Tulare Valley,” and has been found in other localities in Cali- 
