280 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Mar. 11, 



Figs. 11, 12, & 13. — Plagiaulax Becklesii. Fragment consisting of 

 the anterior portion of the right ramus of the lower jaw. Magni- 

 fied 2 diameters. 



Fig. 11. Outer surface. 

 Fig. 12. Inner surface. 

 Fig. 13. Vertical view, seen from above. 



11. 



13. 



12. 



a. Incisor. 

 pm. Premolars. 



b. Symphysial harmonia. 



c. Mentarv foramen. 



Fig. 14. — Plagiaulax Becklesii. The left ramus of the lower 

 jaw, nearly perfect, showing the outer surface. Magnified 4 dia- 

 meters. 



a. Incisor. 



b. Condyle. 



c. Coronoid process (broken at the edges.; 



d. Inferior boundary rido;e. 



e. Depression on the base of the coronoid. 



