132 THE DOG IN HEALTH. 



more inbreeding the less vigor at all events, as a rule, 

 whatever else may be attained. 



Pure-bred dogs must, in the nature of the case, be very 

 much inbred as compared with mongrels, which in great 

 part explains why they are less hardy and more liable 

 to all sorts of derangements. 



The problem with the breeder narrows itself down to 

 this : How can the highest perfection of type in its most 

 comprehensive sense, including physical and psychical 

 qualities, be attained ? The more he strives for form, the 

 more liable is he, perhaps, to fail in some other direction ; 

 for, having got certain strains which meet his ideals pretty 

 well, he fears to introduce outside blood lest he disturb, 

 by the meeting of protoplasm more unlike than that of 

 his own strains, the balance that exists, and thus get, per- 

 haps, a series of " variations " or departures from the type 

 he does not desire. 



"We think the solution lies in this principle : to keep 

 within the lines that give the type as long as there is 

 no sign of deterioration in any direction, notably in size, 

 stamina, or intelligence, which are apt to suffer by inbreed- 

 ing ; but when an outcross is necessary, to introduce one 

 as similar as possible ; in other words, to make departures 

 by gradual steps only. 



Pedigree is indispensable in breeding ; but in consider- 

 ing family lines the conditions under which the animals 

 have lived are of no little moment. To breed a brother 

 an'^ sister brought up in the same kennel is quite a differ- 

 ent natter from breeding the same relatives one of which 

 was reared in England, say, and the other in America. 



As a rule, the less closely animals are bred, provided 



