EXAMINATION OF HORSES 



to be removed by absorption and ankylosed in the 

 manner above described. I have no doubt that in 

 the course of time — and here I refer to time as 

 counted by the geologist rather than as counted by 

 the historian — these lower bones of the hock will 

 become one and lose their light spongy texture, and a 

 more perfect hock will result. // is du?'i?ig this trans- 

 formation stage that spavi7i is produced. All the parts 

 are then more vascular and more susceptible to the 

 effects produced by being pushed and pulled from here 

 to there. Whenever we find a part changing the cha- 

 racter of its life — whether it be from a lower form to 

 a higher, or from a higher to a lower form — we find in 

 it extra activity of the parts whose office it is to build 

 it up and to pull it down (the blood-vessels and the 

 absorbents). And if these builders and carriers are 

 unduly meddled with they at once revolt. Let us take 

 one striking example. Let us look at the mammary 

 gland immediately its owner becomes a mother, and 

 notice how the least extra excitement induces abscess 

 in the generous gland, which is already in the full height 

 of its activity. Then again look at the mammary gland 

 and the uterus in womankind, how extremely prone 

 these structures are to become the seat of cancer at the 

 end of child-bearing, or, in other words, when the need 

 for their activity is past, and when they are therefore 

 passing from a higher to a lower life. Of the several 

 forms of exostosis to which we ourselves are liable, the 

 one which is most like in its nature to splint occurs 



