102 THE NAUTILUS. 
Routt Co.; Pueblo Co. (R. Cusack); Hardscrabble Canon, Custer 
Co.; Black Lake Creek, Summit Co.; Pottery Pass, about 11,500 
feet, Summit Co.; Red Cliff, Eagle Co.; near Glenwood Springs, 
Garfield Co.; near Buzzard Creek, Mesa Co.; Surface Creek, 
Delta Co.; near White Earth Creek, Gunnison Co. 
P. strigosa cooperi form typica Ck. Canon City (T. Morgan) ; 
Cave of the Winds, Manitou (E. W. Roper), and many other 
localities. 5 
P. strigosa cooperi form trifasciata Ckll. Mesa Co. 
P. strigosa cooperi form confluens Ckll. West Mountain Valley, 
Custer Co.; Garfield Co.; Mesa Co. 
P. strigosa cooperi form elevata Ckll. Delta Co. 
P. strigosu coopert var. depressa nov. Shell flattish, max. diam. 
213, alt. 123 mill. Specimens of this variety were sent to me by 
Miss A. Eastwood, who found them in a canon near Durango. 
The same variety is figured by Binney, Man. Amer. Land Shells 
(1885), p. 166, fig. 155. 
P. strigosa cooperi form major noy. Shell with diam. 25 mill. 
Near head of North Mam Creek, Mesa Co., Sept. 14, 1887. 
P. strigosa coopert var. minor Ckll. Near Egeria, Routt Co., 
abundant. It is quite a distinct local race. 
P. strigosa var. hemphilli (Newe.) Williams Canon, Manitou 
(Binney). This perhaps requires confirmation. The examples of 
strigosa | have seen from Williams Canon are ordinary coopert. The 
young of cooperi is keeled. 
P. striatella (Anth.) Twin Lakes and South Park (Yarrow) ; 
Este’s Park (Binney); Grand Co. (Ingersoll); Gilpin Gulch (H, 
Prime); Williams Canon, Manitou (M. E. Cusack); Swift Creek, 
Custer Co.; Kremmling, Grand Co.; Rock Creek, Routt Co.; 
Powderhorn, Gunnison Co.; Divide Creek and near Cattle Creek, 
Garfield Co.; Buzzard Creek, Mesa Co.; Black Lake Creek, Sum- 
mit Co. 
P. striatella form albina (Morse). Near Mam Mts., Mesa Co 
Differs from the type in having a white shell. 
P. ruderata var. cronkhitet (Newe.) Blue River Valley (Inger- 
soll) ; Cottonwood Gulch, Saguache Co. ; Micawber Mine, Chester Co. 
P. ruderata cronkhitet form viridula noy. Shell greenish-white. 
Micawber Mine, Custer Co. 
P. ruderata var. gorktschana Mouss. Ouray Co. (Binney). 
P. (Punctum) pygmea var. minutissima (Lea). Willow Creek, 
