EWART'S TELEGONY EXPERIMENTS 11 



has not proved sufficiently reliable, and Professor Cossar 

 Ewart's extensive telegony experiments at Penicuik with 

 zebra hybrids (zebrules), dogs, and numerous small animals, 

 including pigeons, although supplying only negative evidence, 

 all point in a diametrically opposite direction. He has 

 completely undermined the relevance of the often quoted 

 case of Lord Morton's pure-bred chestnut Arab mare, 

 which first bred to a quagga, and subsequently by a black 

 Arab stallion, gave birth to two dun colts with striped legs, 1 

 by pointing out that similar bandings occur naturally, 

 without crossing, in certain breeds of horses, notably a 

 Norwegian breed ; and by breeding many zebra hybrids the 

 progeny of a great variety of virgin horse and pony mares, 

 followed by foals from the same mares by an Arab stallion 

 not one of which showed any marking or other characteristic 

 which could be traced to the zebra. 



The best bred animals are often, nay usually, far from 

 perfect in some point. It is most important, if a bull (or sire 

 of any breed) with a special defect has been used, that suc- 

 ceeding sires should be strong in that particular point, what- 

 ever it be, else there might in time be a general defect 

 established in the whole race of descendants, such as the 

 hollow or weakness behind the shoulder of many otherwise 

 grand Shorthorns of Bates descent. Males are, in some 

 cases, more variable than females ; for example, in certain 

 breeds of sheep, it is much easier to select a large number 

 of ewe lambs than of ram lambs good enough to be exhibited 

 in a showyard ; and, when breeds of cattle are small in 

 number, it becomes a difficult task to find a bull to mate with 

 the cows good enough to maintain the standard of quality. 



Animals with constitutional weaknesses amounting 

 to unsoundness should not be used for breeding. 2 It is 

 still believed by a limited number of biologists that defects 



1 Darwin's Animals and Plants under Domestication, chap. xi. 



2 " In France all entire horses, whether kept at the Government 

 haras or by private persons, must be examined and passed as fit for 

 service, and no others can be used. The percentage of unsound stallions 

 in France has fallen from 5.84 per cent, in 1880 to 2.93 in 1890, the con- 

 tinuous decline, accompanied by an increase in the number of entire horses, 

 proving the wisdom of the system of inspection." But for the weakness 

 of our system of Government, no stallion would be permitted to travel in 

 this country without a certificate of soundness. 



