iA By 
Plate I, Figs. ta, and b, Premaxillary of Protosphvrena D 
natural S1Ze: 
Protosphyrena bentoniana Stewart. The first natural ‘size, 
second reduced to one-fourth. 
Figs. 3a, and b, Maxillary, mandible, and end view of p 
tary of Saurocephalus dentatus Stewart. One-half natural siz 
Figs. 4a, and 4b, Internal view of maxillary and mandible 
the same. ee 
