PLATE X. 



Pate. 



Fu.s. I ANii la. Platvi i;nAs PAHVUM. 461 



A siiecimen of the usual size, or somewhat larger than usual. The apex is .slightly 



broken. 

 Fig. 1. Side view. 



la. Posterior view. 

 Henuosa formation: Sandstone Mountain, Eieo quadrangle (station 2l'1S). 



Figs. 2 and 2a. Platyceras paevv.m ^ 461 



An extremely large specimen which seems to belong to the same species. 

 Fig. 2. Side view. 



2a. Posterior view. This figure shows the specimen tilted forward and downward. 

 Hermosa formation: Head of Bear Creek, Xeedle Mountains quadrangle (station 2286). 



Figs. 3 and 3a. Stkophostylus subovati-s? 463 



A specimen referred to this species. 

 Fig. 3. Apical view. 



3a. Side view. Neither of these figures show adequately the rapid expansion which 

 characterizes this specimen. 

 Hermosa formation : Sandstone Mountain, Eico quadrangle (station 2217). 



Figs. 4 and 4a. Stkophostylus remex 463 



A large but imperfect specimen of this species. 

 Fig. 4. Apical view. 

 4a. Side view. 

 JRico formation: Scotch Creek, Rico quadrangle (station 2340). 



Figs. 5 to 5b. Steophostylus remex 463 



A smaller specimen referred to this species. 

 Fig. 5. Side view. 

 5a. Apical view. 



5b. Side view, somewhat different from o. 

 Rico formation: Marguerite Creek, Rico quadrangle (station 2:345). 



Figs. 6 to 6b. Bulimorph a chry'salis 466 



A large specimen referred to this species. 

 Fig. 6. Side view. 



6a. Apertural view. The specimen in this figure is inclined away from the vertical. 

 6b. Apical view. 

 Rico formation: Scotch Creek, Rico quadrangle (station 2342). 



Figs. 7 and 7a. Bulimoepha chrysalis 466 



A somewhat smaller and more slender specimen than the foregoing. 

 Fig. 7. Side view. 



7a. Apertural view. 

 Rico formation: Marguerite Creek, Rico quadrangle (station 2345). 

 516 



