STRUCTURE OF FEET. 



one lettered td to a certain extent. This difference may 

 be illustrated by saying that if we were to take a hatchet 

 and chop vertically up- 

 wards between the third 

 and fourth toes of an 

 elephant's foot there 

 would be nothing to resist 

 the passage of the blade 

 till it reached the bones 

 of the leg, whereas in all 

 other living Ungulates, 

 except the hyrax the pig / ^ 

 for instance the blade 

 could not pass through 

 the wrist without cleaving 

 solid bone. Again, where- 

 as ordinary Ungulates FIG. 3. Bones of the Left Fore Foot 

 walk solely on the tips of of an Elephant, one-eighth natural 



size. The lettered bones are those 

 of the wrist or carpus, and the 

 numbered ones the metacarpals, 

 below which are the bones of the 

 toes. (After Osborn.) 



their toes, and are thus 

 termed digiti grade, while 

 the bones of the toes them- 

 selves are more or less 

 elongated, elephants walk 

 on the soles of their feet in the so-called plantigrade 

 fashion, and have very short toe-bones. Now, since 

 all the large extinct Ungulates of the lower Eocene, 

 or earliest Tertiary period, also have five-toed feet, 

 very similar to, but still snorter and of even simpler 

 structure than those of elephants, there can be no 

 doubt as to the extremely primitive plan on which the 

 entire limbs of the latter are constructed. As regards, 

 therefore, its limbs and feet, an elephant may be said to 

 be an essentially old-fashioned animal. 



If, however, we turn to their teeth we shall find that 

 elephants are very far indeed from being of a primitive or 

 old-fashioned type ; the truth being that they are, on the 

 contrary, very peculiar and specialized in this respect. 

 The first and most obvious peculiarity in regard to their 

 dentition is to be found in their tusks, which correspond 

 to one of the pairs of upper front teeth in man, and 



