<>!■ CX/T I 11AUM TE}I> 



273 



96.0-104.5 



52.5-60.0 

 64.0-76.5 



The above indices prove that the mule has not a primi- 

 tive skull like that of the ass on a larger scale, but has 

 essentially the skull of the horse, namely : 



1. A long, narrow skull, as a whole. 



2. A long diastema, or space for the bit. 



3. A short cranium and a long face. 



4. A long, oval orbit. 



5. A relatively elongate and narrow set of grinding 

 teeth. 



6. A vertically placed occiput. 



The one character in which the mule resembles the ass 

 is the elongation of the vomer behind the bony palate. It 

 should, however, be distinctly stated that while the indices 

 given above are those which probably prevail in mules, 

 there are overlaps in the (4) orbital index and (6) occi- 

 put-vertex angle. Thus in one mule the orbital index 

 agrees with that of one of the asses. 



Enamel Pattern of Grinding Teeth.-ln the marvel- 

 ous! v complex pattern of the grinding teeth the ' 'unit 

 character" transmission is quite sharply denned in the 

 majority of characters, while intermediate or slightly 

 blended'in the minoritv. In general in the grinding teeth 

 of the ass the main enamel folds are less complicated 



