46 THE HORSE AND ITS RELATIVES 



vanished toes. Pursuing this aspect of the subject 

 still further, it should be borne in mind that, as I 

 have pointed out in an article in the Proceedings 

 of the Zoological Society of London for 1903, the 

 chestnuts of the horse are situated on the inner 

 surface, whereas, if they represented vestigial foot- 

 pads, their position should be, prima facie, on the 

 hind aspect, as is the case with the ergot. It might, 

 indeed, be argued that they have changed their 

 original position, but of such a shifting there is 

 no evidence in the adult horse. A second, and 

 perhaps more important, objection to the foot- 

 pad theory may be drawn from the fact that the 

 chestnuts in the fore-limb are situated above the 

 so-called knee-joint (carpus), and are therefore 

 altogether higher up than any of the foot-pads of 

 plantigrade mammals. Unless, therefore, another 

 shift of position has taken place, the fore-chest- 

 nuts do not represent foot-pads. This argument 

 was used by Sir W. H. Flower to disprove the 

 theory that the chestnuts are remnants of lateral 

 toes. 



The hind-chestnuts, on the contrary, are situated 

 a short distance below the joint of the hock (tarsus), 

 and are therefore on a part of the limb, although on 

 its inner side, which is included in the foot of a 

 plantigrade mammal. If, however, the front-chest- 

 nut be regarded as corresponding in a general way 

 with the hind one, it will be evident that in the 



