142 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



EXPLANATION OF PLATE VL 



Page. 

 Pachydiscus sacramenticus, sp. nov. 105 



Fig- 133- Full grown shell. 



Fig. 134. Young shell. 

 Pachydiscus merriauii, sp. nov. 103 



Figs. 135-136. Full grown shells. 



Figs. 137-138. Younger coils. 

 Lytoceras (Gabbioceras) aiigulatiini (Gaisb's var.), sp. nov. 87 



Fig- 139- Partial restoration of an adult shell. 

 Lytoceras rel. duvalianum d'Orb. 81 



Figs. 140-143. Partly grown shells. 

 Schlcenbachia oregonefisis, sp. nov. 122 



Fig. 144. Cross-section of whorls; 22.25 mm. diameter. 

 After J. P. Smith. 



