238 ANIMAL LIFE PAST AND PRESENT. 



the monk's cowl. Many other similar cases will occur 

 to the reader, but the above are sufficient for our 

 present purpose. 



Some of the best instances in nature of rudimentary 

 structures are to be found in the feet of the Hoofed or 

 Ungulate Mammals, or that great group which includes 

 Horses, Ehinoceroses, Cattle, Deer, Elephants, &c. In 

 the Elephant and many of the earlier extinct members 

 of this group each foot (as we have already mentioned 

 in the article on " Teeth and their Variations ") was 

 furnished with five complete toes, each of which was 

 supported by a separate bone, connecting it with the 

 wrist in the fore limb, and, with the ankle in the hind 

 limb. These five connecting bones in the fore limb (to 

 which we will confine our attention) correspond with 

 those forming the upper part of our own hand, and, 

 as following the wrist or carpus, are termed the meta- 

 carpal bones, or metacarpus. With the exception of the 

 elephant the number of the fingers and metacarpals in 

 all living Ungulates is, however, always less than five, 

 the first finger, or that corresponding with our thumb, 

 having invariably disappeared. In the Even-Toed 

 Ungulates, such as Pigs, Deer, and Cattle, where the 

 middle pair of fingers or hoofs (corresponding to our 

 third and fourth fingers, the thumb being reckoned as 

 the first) are always symmetrical to one another, we 

 find as we advance to the more specialised species a 

 gradual diminution in the relative size of the second 

 and fifth metacarpals, as compared with the middle 

 pair. Thus in certain extinct Pig-like Animals the 



