424 CLASSIFICATION OF THE EQUID^. 



are North African horses) with chestnuts on their hind 

 legs. 



A breed is an actual, not a theoretical, collection of 

 individuals, which may, or may not, have a common 

 origin. Hence, it is not correct to apply the term 

 breed to particular members of one or more breeds, on 

 the ground that such members are, respectively, possessors 

 of distinctive characteristics. Professor Ewart most reason- 

 ably points out that descendants of two or more separate 

 equine varieties may exist in the same breed, and that, 

 in ancient days (presumably in Pre-glacial times), there 

 was an equme variety without ergots and hind chestnuts, 

 and another variety with these callosities ; the former 

 being certainly of a newer type than the latter. 



Retzius, the Swedish anthropologist, divided mankind 

 into brachycephalic (short-headed) and dolichocephalic 

 (long-headed) varieties ; this classification* being made 

 with reference to the proportion between the transverse 

 and longitudinal diameters of the skull. Many zoologists 

 apply this form of classification to horses ; and speak of 

 some breeds of horses as having big heads, and of others 

 as having small heads. In doing this, they usually appear 

 to compare the size of a horse's head with his height, and 

 consequently they call a thorough-bred, a small-headed 

 horse ; and a Shire, a big-headed horse. Here we must 

 take into account the fact that the height of an ordinary 

 horse is chiefly dependent on the length of his legs, 

 which is of a very variable nature. I have found that 

 the proportion between the length of a horse's head and 

 that of his body (pp. 184 and 186) is practically the same 

 in all the many breeds of domesticated horses which I 

 have examined in Europe, Asia and Africa, and that the 

 length of the head is about equal to the depth of the 



* Lord Avebury states that " we class those skulls in which the relation of the breadth 

 to the length is less than 73 to 100, as long heads or dolichocephalic ; those in which it is 

 from 74—79 to 100 as medium heads, and those in which the proportion is 80 or more than 

 80 to 100 as short heads, or brachycephalic." West African Negroes are said to be 

 dolichocephalic ; and Europeans, brachycephalic. 



