LEIDY'S OSTEOLOGY OF THE HEAD OF HIPPOPOTAMUS. 



221 



The remainder of the skeleton of Chocropsis corresponds so closely in its anatomical 

 details with Hippopotamus, so far as can be ascertained from comparisons with the 

 excellent figures in the Osteography of De Blainville, that a few remarks only are 

 necessary to complete the description of the animal. 



The number of vertebrae and ribs are the same in Choeropsis as in Hippopotamus, 

 there being forty-seven of the former, and fifteen pairs of the latter. 



In the skeleton of Choeropsis there are four lumbar vertebrae, of which the last, 

 from its transverse processes, sends backwards an apophysis to join the corresponding 

 portions of the sacrum. 



There are also in the specimen, five sacral vertebrae, of which the first two pieces 

 only join the ilia, and the second and third, and fourth and fifth are ossified together. 



Of the three skulls of ChcEropsis which have been designated, though of different 

 ages : one being an old female, the second an adult male, and the third a young, but 

 nearly adult male, the measurements are nearly alike. 



Admeasurements of the Head. 



Length from inion to end of ossa nasi, 



" occipital condyles to incisive alveoli, 



" of ossa nasi, ....... 



" forehead in middle line, .... 



Distance from anterior margin of orbit to incisive alveoli, 



Heighth of inion from inferior margin of occipital foramen, 



Greatest breadth of inion. 



Greatest breadth of head at zygomse, 



" " forehead at pcst-orbitar processes 



Greatest breadth at infra-orbitar foramina, 

 " " canine alveoli 



Breadth of ossa nasi at middle, 



Vertical diameter of orbit. 



Transverse " " . . 



Length of hard palate, 



Breadth of do. between first true molars, 



Greatest length of lower jaw, 



Heighth at first true molar, 



" from angle to coronoid process, 

 " " condyle, 



Breadth at angles, .... 



at canine alveoli, 

 between first true molars, 





Nearly ac 



»lts 



Old 



9 



In. 



Lines. 



In. 



./.. 



11 



6 







12 



6 



12 



9 



5 



9 







3 





3 





6 



9 



7 





4 





4 





5 



9 



5 



9 



7 



9 



8 





5 



3 



5 



6 



3 





3 





5 



6 



6 





1 



6 







2 



2 



2 



2 



1 



2 



1 



9 



8 





8 



6 



1 



4 



1 



4 



9 



6 







2 



3 







5 



6 





, 



4 



6 







7 



6 







4 



6 







1 



9 







56 



