ACKRODON. 413 



Differential characters, as compared with dentition of Pterojuis. — 

 Cingulum of p* and ni' t'ornnng a well differentiated tubercle 



Fig. 20. — Accrodonjubatusj'ubatus, 2- S. I^egros. Ko. 77.12.10.11. }. 



antero-intemally, making these teeth distinctly tritiibercular : a 

 high outer, low inner, and smaller antero-internal cusp; a similar, 



