38 BOARD OF AGRICULTURE. [Pub. Doc. 



Professor Brigham. About a hundred years. 

 Mr. Thayer. A few years ago I had some Plymouth 

 Rocks, and by picking out the handsomest rooster in my 

 yard, which was a dark-colored one, in three years' time I 

 ran my fowl into all black. How are we going to breed to 

 keep the flock good? 



Professor Brigham. Simply by not picking out the dark 

 ones. A black one is simply what we call reverted, gone 

 back to the old black type from which the Plymouth Rock 

 originated, and you have to look out. That is where the 

 brains come in. You can breed Plymouth Rocks without 

 going outside your flock. You have to breed even lighter, 

 perhaps, than you wish. That is where experience comes 

 in, and you gain the means of mating. In mating you do 

 not always get a third bird like those two, except in a parti- 

 colored bird like the Plymouth Rock. It is done by selec- 

 tion, and using lighter colored fowl than you expect to have 

 in the progeny. 



jVtr. Thayer. In that way, if you want to increase the 

 size, you would pick out the largest to breed from? 



Professor Brigham. Certainly ; if you want to get deeper 

 breasts, pick out those with deep breasts and plump shanks ; 

 if you want larger shanks, pick them out in the parent. I 

 want you, however, to keep this in mind, — that a bird may 

 have a deep breast and not be able to transmit it, while 

 another bird may transmit that (quality strongly. The latter 

 bird is prepotent, we say. It is one thing to possess a 

 quality ; it is another thing to be able to transmit that quality 

 to your progeny. 



Question. Would you advocate keeping the old cock 

 for the young pullets for the next season? 



Professor Brigham. That is just the thing to do ; that is 

 line breeding. Breed pullets to sire, and breed cockerel to 

 mother, and in that way 3'ou can keep two lines going. 



Question. What do you say about the single mating 

 question ? 



Professor Brigham. That is a good deep question. I 

 say single mating, and there is only one excuse for double 

 mating. In double mating, a pair of birds are mated to 



