Plate I 
Figures 1-3. Oreohelix cooperi limitaris (Dawson).. Series of three specimens from Waterton 
lake, Alberta; natural size. (Geol. Surv., Can., Cat. No. 2881.) 
Figure 4. Oreohelix cooperi limitaris (Dawson). Immature specimen from Waterton lake, 
Alberta; natural size. (Geol. Surv., Can., Cat. No. 3144.) 
Figure 5. Oreohelix cooperi limitaris (Dawson). Specimen shown in Figure 1; x 2. 
Figure 6. Oreohelix strigosa canadica n. subsp. The type specimen from Donald, B.C.; natural 
size. (Geol. Surv., Can., Cat. No. 2882.) 
Figure 7. Oreohelix strigosa canadica n. subsp. Same specimen; x 2. 
Figure 8. Gonyodiscus shimekii (Pilsbry). Specimen from Kananaskis, Alberta; x 6. (Geol. 
Surv., Can., Cat. No. 2937). 
