THE LIMBS 



171 



sionally even making a horn-like projection. Their 

 structure, in fact, is much like that of a wart or corn, 

 but they are not the results of pathological changes, 

 though often treated as such in old works on veterinary 

 surgery. Even so enlightened a writer as Youatt 

 includes them among diseases, and prescribes remedies 

 both external and internal for the purpose of getting 

 rid of them. They are, however, perfectly normal 

 structures ; they exist at birth, are equally developed in 

 both sexes, and (allowing for certain limited individual 

 variations) constant in form, size, and position. They 

 constitute, moreover, one of the characteristic distinc- 

 tions by which the species Uquus caballus is distin- 

 guished from the other members of the genus. 



They differ in form in the two limbs, but in both 

 are placed upon the inner surface and nearer the hinder 

 than the front border. That on the fore limb is above 

 the carpal or wrist joint ( c knee ' of the horse), that on 

 the hind limb below the ankle or c hock' joint. The 

 former is about two inches long and three-quarters of 

 an inch wide, pointed at each end, and lying obliquely, 

 so that the long axis has its lower end directed 

 backwards almost to the posterior border of the limb. 

 When all the loose epidermis which encrusts it to a 

 variable extent during life has been removed, the sur- 

 face is seen to be elevated above the surrounding skin 

 and to have definite prominent margins, and also to be 



