THE HORSE 69 



tirely suppressed, under domestication, we find 

 that horses are subject to a certain amount of 

 variation in the number of bones which go to 

 make the hock joint, and these differences no 

 doubt have a certain elfect on the capabilities of 

 the individual Tlie tendency is, of course, for 

 the number of bones to diminish in correspondence 

 with the loss of the toes with which they were 

 once articulated, but owing to reversion some 

 horses possess additional rudimentary bones in the 

 hock which are of no use, and should not actually 

 be there. It is probably this variation, and the 

 consequent instability of the joint, which indi- 

 rectly causes horses to be so predisposed to spavin 

 and other bone diseases in this region. It will be 

 seen, on reference to the diagram of the hock, that 

 there is normally on its inner side a column of 

 bones composed of the astra^galus, large cuneiform, 

 and median cuneiform, which rest on the meta- 

 carpal or cannon bone. Owing to jar, strain, or 

 work, the bones become inflamed, usually between 

 the metatarsal and median cuneiform, or between 

 this and the large cuneiform. Inflammation of 

 bone, its covering membrane, and its articular 

 cartilages, always leads to abnormal limey depos- 

 its at the seat of inflammation, hence the result 



