392 BuUetin American Museum of Natural History, [Vol. XIX, 



obliquely arranged on descending levels from .within outward 

 and from in front backward, the whole region having been 

 thickened by the separation of the inner and outer tabulae of 



P.mx.^ 



Ex.o: 



Fig. 3. Side view. From Osborn. 



all the bones, and also sharing in the upward-and-backward 

 tilting of the nasal region and in the general fore-and-aft 

 squeezing of the skull, the end result being that the foramina 

 have been pulled out into long tunnels running obliquely for- 



