APPLICATION OF PRINCIPLES OF BREEDING 479 



is possible under natural conditions, it is better than natural 

 selection. The difference between the common type of a wild 

 race and the finest type of the same race in domestication is a 

 measure of the difference, in its value to man, of natural and 

 artificial selection. 



Poultry standards. The continuance and distribution of a 

 specific type or variety in domestication depend upon the agree- 

 ment of breeders on a standard for that type. In the development 

 of a breed or variety in any locality an unwritten standard is gradu- 

 ally evolved, and the breeders are loosely governed by that standard. 

 When a variety is widely distributed and competitive exhibitions 

 bring together stock from many localities, a written standard be- 

 comes necessary. Unwritten standards, as a rule, relate only to the 

 most conspicuous features of a type, and allow great variation in 

 details. Written standards undertake to establish size and weight 

 and to describe every visible character. They are usually mere 

 outlines, and often seem vague to those not familiar with the varie- 

 ties described and with the popular types. Even when descriptions 

 are supplemented by pictorial illustrations, a written standard is 

 quite inadequate as a description of a variety. In studying a stand- 

 ard the novice must use as illustrations live birds of known values 

 as commonly measured by that standard. The standard of a breed 

 or variety describes the assumed perfect type of every character of 

 that variety. Such a standard is ideal, in that the model form of 

 each and every character is not often found in any one bird.^ The 

 ordinary view of standards makes such a standard (in theory) the 

 ideal toward which all breeders are striving. Actually, considering 

 the relations of a standard to its variety at different periods of the 

 history of the variety, and the inevitable differences in interpretation 

 of its provisions, a written standard only indicates general direc- 

 tions and bounds, and the exact type in style at any time can be 

 learned only by observation of the type that wins most prizes at 

 leading shows. 



The term "'standard" is technically (but not discriminatingly) 

 used in this country with specific reference to varieties described in 



1 The technical fiction is that the perfect bird cannot be produced. While the 

 proportion to the whole number is small, many birds are produced which only 

 hypercritical judgment can find fault with. 



