POSITION AND STRUCTURE OF HORSE 45 



Beddard, 1 who in one passage states that the chest- 

 nuts on the fore-limbs probably correspond to glands 

 found in the neighbourhood of the wrist or carpus 

 in certain other mammals, although on a subsequent 

 page the glandular nature of these structures is 

 questioned. In another and apparently later com- 

 munication the same writer 2 suggested that the 

 front chestnuts may represent a carpal sense- 

 organ, of which remnants are believed to exist in 

 the bristles on the wrists of the African hyraxes, 

 the sole survivors of a formerly numerous group of 

 ungulates. This degeneration of such a sense- 

 organ might, it is suggested, result in the formation 

 of a structure like a chestnut. 



On the other hand, there exists an idea that the 

 chestnuts represent vanished toes or foot-pads. 

 This theory has been supported by Professor J. C. 

 Ewart 3 of Edinburgh, and more recently by a 

 German writer, Mr. R. Hintze, 4 who compares the 

 hind chestnuts to the pads on the foot of a 

 kangaroo. 



If, however, the identification of the horse's 

 ergot with the hind foot-pad of the tapir and the 

 dog be admitted and the evidence in its favour 

 is very strong it is practically certain that the 

 chestnuts cannot represent foot-pads, much less 



1 Cambridge Natural History Mammalia^ pp. 12, 13, and 240. 



2 Proc.ZooL Soc. London^ 1902, vol. i. p. 135. 



3 See Nature -, London, vol. Ivii. p. 239, 1903. 



4 ZooL Anzeiger^ Leipzig, vol. xxv. pp. 372-382, 1910. 



