EXPLANATION OF PLATE IL 



Figs. 1-2. Cionodon arctatus, one-half natural size. 



Fig. 1. Proximal end of tibia from front : a, from outside ; 6, from inside ; c, from above. 



2. Distal end of the tibia from the side : a, from below. 

 Figs. 3-5. Vertebra) of Polyonax vwrtuarius, one-half natural size. 

 Fig. 3. Anterior dorsal, articular face of centrum : a, side view of centrum. 



4. Anterior dorsal, articular face of centrum : a, side, and b, lower face of the same. 



5. Posterior dorsal or lumbar vertebra, side view of centrum : a, inferior view ; b, articular face. 



