220 BULLETIN OF THE 



progenitor of tudiculata, arrosa in turn having evolved . from its northern 

 neighbor, H. Townsendiana, Lea, and Townsendiana from the form we now 

 call H. ptychophorus, Brown, found in Eastern Oregon and Idaho. 



Habitat. Mountains of San Diego County, California. Only one specimen 

 found. 



Helicodiscus fimbriatus, var. Salmonensis. 



This variety varies from the Eastern or typical forms in the absence of the 

 revolving lines; otherwise the shells are alike. 



Habitat. Banks of Salmon River, Idaho, Old Mission, Idaho, and Oakland, 

 California. 



Helix Kelletti, var. albida. 



This is a beautiful clear white translucent variety, with no markings or 

 stains of any kind. It is quite thin and frail, and a trifle smaller than the 

 average size of Kelletti. 



Habitat. Santa Catalina Island, California. Two specimens only found 

 by me. 



Helix Kelletti, var. castanea. 



Among the numerous patterns of coloring assumed by H. Kelletti, none are 

 more conspicuous than this well marked variety. The body whorl is of a 

 deep shiny chestnut-color above the periphery, and becomes lighter as it fol- 

 lows the whorls of the spire to the apex. The band at the periphery is quite 

 variable in the different specimens ; it is generally light, and well defined 

 above, but below it is irregular and spreads over the base of the shell more 

 or less. 



Habitat. Santa Catalina Island, California. This variety is not rare. 



Patula strigosa, var. Buttonii. 



Shell umbilicated, elevated, or moderately depressed, nearly white, some- 

 times stained with light chocolate; whorls five, convex, with numerous oblique 

 striae ; suture impressed, aperture circular ; peristome thickened, not reflected, 

 darker than the body of the shell; extremities nearly approached and joined 

 by a callus; with or without a basal tooth ; tooth when present very variable, 

 generally consisting of a single tubercle ; in some specimens it is nearly or 

 quite square, as high as long ; in other specimens it is long and bifid. 



Diameter of the largest specimen, | inch ; height, •£ inch. Diameter of the 

 smallest specimen, \ inch ; height, f inch. 



Habitat. Box Elder Co., Utah. 



I dedicate this interesting form of strigosa to my friend, Mr. 0. Button, of 

 Oakland, California. 







