•I2Q CALIFORNIA ACADEMY OF SCIENCES [Proc. 4tu Ser. 



EXPLANATION OF PLATE 12. 



Fig. la. Pseudoliva dilleri, new species, xl. Mouth view. 



Fig. \b. Pseudoliva dilleri, new species, xl. Back view of same speci- 

 men as Fig. la. 



Fig. \c. Pseudoliva dilleri, new species, xl. Back view of small in- 

 dividual. 



Fig. \d. Pseudoliva dilleri, new species, xl. Mouth view of individual 

 figured as Fig. \c. 



Fig. 2a. Amauropsis andersoni, new species, xl. Back view of type 

 specimen. 



Fig. 2b. Amauropsis andersoni, new species xl. Mouth view of type. 



Fig. 3a. Amauropsis umpquaensis, new species, xl. Mouth view of type. 



Fig. 3b. Amauropsis umpquaensis, new species, :>i\. Back view of type. 



Fig. 4a. Ancilla (Oliverato) calif ornica Cooper, xl. Back view. This 

 species is characteristic of, but not restricted to, the Siphon- 

 alia sutterensis Zone. 



Fig. Ab. Ancilla {Oliverato) californica Cooper, xl. Mouth view. 



Fig. 5a. Natica hannibali, new species, xl. Back view. 



Fig. 5b. Natica hannibali, new species, xl. Mouth view. 



