PLATE XX. 



Placenticeras (Perezian0m ? vav.) Liardense (page 158). 



Figure 1. Side view of a small but nearly perfect gpeciaien of this siiell, from 



the Liard River near old Fort Halkett. 

 Figure 2. Side view of a fragment of a large specimen of the same species, 



and from the same locality. 



