PLATE XIII. 



PAGE 



F - 16 AMMONITES BATESII. 



16 a. Section of volution. 

 b. Septum. 



00 



Fi 17 A. CHICOENSIS. 



a. Section of volution. 



b. Septum. 



70 

 Fi 18 HAMITES VANCOUVERENSIS. 



Natural size. 



Fi 19 HELICOCERAS VERMICULARIS. 



19 a. Section. 

 b. Septum. 



74 

 Fio . 20 PTYCHOCERAS .EQTJICOSTATUS. 



Natural size. 



