POSITION AND STRUCTURE OF HORSE 49 



in nature. And it is possible that these may 

 represent the fore-chestnuts of the horse, for there 

 seems no good reason why the position of a gland 

 should not have somewhat shifted in two widely 

 separated groups of mammals. Then, again, we 

 have the carpal bristles of certain mammals, such 

 as the South American coatis and the hyraxes, 

 already referred to as the remnants of a " scent- 

 organ " — a structure probably not far removed in 

 its nature from a gland. The occurrence of these 

 bristles in the hyraxes is very important. Mr. 

 Beddard states that these are the only ungulates in 

 which he has found these bristles. Carpal callosities 

 are, however, described by Dr. W. Leche^ as 

 occurring in wart-hogs {PhacochcErus) ; although 

 they are stated by their describer to be acquired, 

 and not primitive structures. Of special importance 

 is the occurrence of bristles in these structures, 

 since, even if hairs be found to exist on the 

 callosities of foetal Equidce, this would be no bar to 

 the supposition of their glandular nature. 



More recently, in the Bulletin de la Societe 

 Scientifique et Medicale de l" Quest for July 1909, 

 Veterinary Surgeon J. Roger directed attention to 

 the presence on the inner and hind surface of the 

 fore-legs of pigs, in proximity to the wrist or carpal 

 joint, of a patch of large pores, which in certain 

 circumstances exude a transparent and slightly 



^ Biol. Centralblatt, vol. xxii. p. 79, 1902. 



D 



