PRACTICAL AND SCIENTIFIC BREEDING 
Upon this theory the ordinary breeding by selection is 
based. In case of breeding for show room, the breeder’s eye, 
or the judge’s score card, is the tape with which to measure 
the length of the giraffe’s neck. This principle can be applied 
equally well, even better, to characteristics where accurate 
Measurement may be used. 
The last forty years of scientific progress has established 
firmly the general theories of Darwin, but they have also 
resulted in our questioning his idea that all great changes are 
due to the sum of small variations. Many instances have 
been suggested in which the theory of gradual changes could 
not explain the facts. 
The theory of mutation, of which Hugo de Vries, of Hol- 
land, is the chief expounder, does not antagonize Darwin, but 
simply gives more weight in the process of evolution to the 
factor of sudden changes commonly called sports. Let us 
illustrate: In the giraffe of our former forest, one might dp- 
pear whose neck was not longer because of slightly longer 
vertebrae, but who possessed an extra vertebrae. This would 
be a mutation. In other words, a mutation is a marked vari- 
ation that may be inherited. We now believe that polled cat- 
tle, five-toed Dorkings, top-knotted Houdans, frizzles and black 
skinned chickens arose through mutations. 
Burbank’s Methods—The wonderful Burbank with his 
thornless cactus, his stoneless plum, and his white blackberry, 
is simply a searcher after mutations. His success is not 
because he uses any secret methods, but because of the size 
of his operations. He produces his specimens by the millions, 
and in these millions looks, and often looks in vain for the 
lonely sport that is to father a new race. Burbank has, with 
plants, many advantages of which the animal breeder is de- 
prived. He can produce his specimens in greater number, he 
can more easily find out the desirable character, and in many 
plants he has not the uncertain element of double parentage 
to contend with, while with others he is still more fortunate, 
as he can produce them by seed, stimulate variation until the 
desired mutation is found and can then reproduce the desired 
variation with certainty by the use of cuttings. This latter 
is not true inheritance with its inevitable variation, but the 
indefinite prolongation of the life of one individual. In this 
sense there is only one seedless orange tree in the world. 
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