50 THE HORSE AND ITS RELATIVES 



glutinous fluid. After describing these sudoriparous 

 glands in some detail, the writer suggested that 

 they correspond to the chestnuts of the horse, or 

 rather that the chestnuts represent the sudoriparous 

 glands of the pigs in a decadent condition. The 

 fact that those of the horse yield when cut a sticky, 

 strong-smelling fluid favours this interpretation, 

 which also accords fairly well with the theory that 

 the chestnuts represent structures more or less 

 similar to the foot-glands of deer. 



As regards the structure of the chestnuts them- 

 selves, it may be noted that in the horse both pairs 

 are of a distinctly warty nature, and that the hind 

 pair is certainly in a more decadent condition than 

 the other, being in fact on the verge of disappearing. 

 In the zebras, on the other hand (in which the hind 

 one has been lost), the fore- chestnut is larger and 

 much less warty and also situated higher up. In 

 dried skins it is, in fact, much more like the pale 

 glandular patch of skin below the ear of a reedbuck. 

 In this connection not only should Mr. Beddard's 

 observations be borne in mind, but attention may 

 be directed to others by Mr. Bland Sutton,^ in which 

 it is pointed out that in certain lemurs decadent 

 glands are actually converted into bunches of spines, 

 which are practically almost the same as warts ; 

 that is to say, they are excessive growths of some- 

 what abnormal dermal tissue. Hence there seems 



^ Proc. Zool. Soc, 1887, p. 369. 



