EFFECTS OF RIGID SELECTION. 113 



by a similar method is capable of development and fixture ; 

 whilst any colour of plumage or of leg may be obtained and 

 established in the same way. The original amount of character 

 required is very slight ; a single hen-tailed cock will be enough 

 to give that characteristic to a whole breed ; and the amount 

 of white face which often troubles the breeder in Leghorns and 

 Black Hamburghs would be quite enough to lay the foundation 

 of new white-faced varieties. 



Any peculiarity of constitution, such as constant laying, 

 or frequent incubation, may be developed and perpetuated 

 in a similar manner, all that is necessary being care and 

 time. 



That such has been the method employed in the formation 

 of the more distinct races of our poultry, is proved by the fact 

 that a continuance of the same careful selection is needful to 

 perpetuate them in perfection. If the very best examples of a 

 breed are selected as the starting point, and the produce is bred 

 from indiscriminately for many generations, the distinctive 

 points, whatever they are, rapidly decline, and there is also a 

 more or less gradual but sure return to the primitive wild type, 

 in size and even colour of the plumage. The purest black or 

 white originally rapidly becomes first marked with, and ulti- 

 mately changed into, the original red or brown, whilst the other 

 features simultaneously disappear. 



If, however, the process of artificial selection be carried too 

 far, and with reference only to one prominent point, any breed 

 is almost sure to suffer in the other qualities which have been 

 neglected. This has been the case with the very breed already 

 mentioned the white-faced Spanish. We know from old 

 fanciers that this breed was formerly considered hardy, and 

 even in the winter rarely failed to afford a constant supply of 

 its unequalled large white eggs. But of late years attention 

 has been so exclusively directed to the " white face," that 

 whilst this feature has been developed and perfected to a degree 



