PLATE XIII. 



PAGE 



Fig. 16. Ammonites Batesii. 67 



16 a. Section of volution. 

 b. Septum. 



Fig. 17. A. Chicoensis. 68 



a. Section of volution. 



b. Septum. 



Fig. 18. Hamites Vancouterbnsis. 70 



J Natural size. 



Fig. 19. Helicoceras vermicularis. 71 



19 a. Section. 

 b. Septum. 



Pig. 20. Ptychoceras .equicostattts. 74 



Natural size. 



