PROCEEDINGS 



OF THE 



CALIFORNIA ACADEMY OF SCIENCES. 



Third Series. 

 Geology. Vol. I, No. 4. 



The Development of Lytoceras 

 and Phylloceras. 



BY 



James Perrin Smith. 



With Five Plates. 



Issued September 20, i8g8. 



SAN FRANCISCO: 



Published by the Academy. 



1898. 



