EXPLANATION OF PLATE XVI. 



View of crania of Pi/llwiwmorjika, from above, one-half natural size. 



Fig. 1. Clhlastes tort or ; 6, premaxillary bone, from below. 



2. Platecarpus mudgei, frontal and parietal bones. 



3. Platecarpus oori/phwns, frontal bone only. 



Figs. 4-5. Platecarpus curlirostris : 4, frontal and parietal bones, from above; 5 premaxillary and adja- 

 cent part of right maxillary bones, from left side and below. 



