ANATOMY OF MEGAPTERA LONGIMANA. 



177 



TABLE II. Measurements of the Mandible, 

 given in inches. 



25. CHARACTERS OF THE MANDIBLE IN COMPARISON WITH THOSE 

 OF B. MUSCULUS. 



Coronoid Process. [In B. musculus the coronoid process is high 

 (8^ inches behind, 4^ in front) and curved forwards. The anterior 

 margin has a concavity of about 1 inch deep ; the posterior margin is 

 very convex on its upper half, concave (concavity |- inch deep) on its 

 lower half. The inner surface is nearly flat ; the outer surface is 

 concave vertically. The process is moderately everted on its upper 

 half, but mainly owing to the concavity of its outer surface. The 

 outer surface has a strong beam, marking off the anterior third as 

 a deep groove on the upper third of the process, large enough to 



