GENERAL INTRODUCTION. liii 



occasional scarcity of food during summer, as effectively 

 get rid of the weaklings and the overgrown individuals 

 as a prolonged dry season decimates the zebras, ante- 

 lopes, and other grass-eaters in Central Africa. It is not 

 difficult to realise how unfavorable surroundings would 

 systematically and persistently operate in the prairies and 

 savannahs in almost the opposite direction to that fol- 

 lowed by breeders of thoroughbreds. The process of 

 elimination would be mercilessly at work amongst the 

 foals, and proceed without rest or pause during colthood, 

 maturity, and old age. 



The foals unable from the first to keep up with their 

 dams would soon perish, the colts that strayed would 

 often have'a like fate, while both old and young, inca- 

 pable of withstanding periods of drought or other un- 

 favorable circumstances, would one by one drop from the 

 ranks, and fall an easy pi'ey to the puma, jaguar, and 

 other flesh-eaters. 



By the ruthless destruction of immense numbers — not 

 necessarily only the unfit, as we are too apt to take for 

 granted — the old troops would occasionally be broken up, 

 and new and differently constituted troops (including a 

 number of unrelated individuals) would be formed, with 

 the result that the evil effects of inbreeding would be 

 minimised, if not absolutely counteracted. A correspond- 

 ing destruction of the fit and unfit alike has, of course, 

 been impossible amongst our race-horses during the two 

 centuries tha.t have elapsed since the introduction of 

 Byerly Turk. 



I have been recently, in a small way, testing the con- 

 stitution of various breeds at different ages. Perhaps, 

 the conditions being somewhat unfavorable, the test has 

 been too severe. The plan has been to see how long 

 various breeds may safely be left out night and day in a 

 large field nearly 700 feet above the sea level, but sur- 

 rounded by woods and sloping on all sides from a central 

 plateau. Large sheds are available, and abundant food is 

 provided. A number of ponies continuously out during last 

 winter (1897—98) did extremely well. Amongst others 



