EXPLANATION OF PLATE 18 

 Fauna of Martinez Eocene 



Fig. 1. Aturia mathewsonii Gabb. X 1. 



This cephalopod occurs both in Martinez and Tejon. 



Fig. 2a. Nautilus stephensoni, n. sp., side view. X 1. 

 Fig. 2b. Nautilus stephensoni, n. sp., back view. X 1. 



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