aii 
1894.] Animal Mechanics. 571 
readily impaired and finally lost. The old race characters, 
under careless management, have an advantage over the more 
unstable acquired characters that give the animal its greatest 
value. 
Pedigrees must be studied to ascertain whether all ancestors 
have had the desired qualities. Cross breeding, in the widest 
sense of breeding together animals of distinct breeds, would 
not now be defended by any intelligent breeder, but the same 
principle is frequently acted upon in breeding together differ- 
ent families of the same breed, and unless there is a strong 
prepotency on the one side, the advantages of such crossing 
must be at least problematical. 
Uniformity in hereditary characters, so far as we know, can 
only be secured by breeding together animals having the 
same characteristics. 
The whole matter of successful breeding may be summed 
up in the two words “culture” and "herédity," and in the 
selection of breeding stock itis desirable that all ancestors 
should have had the required form of culture, or training, in 
order to secure uniformity in hereditary characters. 
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