228 MAINE AGRICULTURAL EXPERIMENT STATION. I914. 



In accordance with the paragraph numbered 2 above only 

 females will be used by the practical breeder which have been 

 shown by trap-nest records to be high producers. All such 

 females will, in the terminology used in Bulletin 205, fall in 

 either Class i or Class 2 of females. In the diagrams a high 

 producing female is shown in solid black; a mediocre or low 

 producer (female) is indicated by fine cross-hatching; a very 

 poor producer, which lays few eggs in its lifetime and none at 

 all in the winter period, is indicated by a mere outline without 

 any filling whatever. 



It is shown in Bulletin 205 that there are nine different types 

 of males, with respect to inherited qualities of egg production. 

 These are numbered in order i to 9. In the diagrams the results 

 of mating each one of these nine different types of males with 

 a flock of high laying hens is shown. In making these diagrams 

 it is assumed that one-half of the flock of high laying females 

 will be Type i females and one-half will be Type 2 females, as 

 described on page 306 of Bulletin 205. This is a fair assump- 

 tion from the practical standpoint. By trap-nest records alone 

 the breeder cannot tell whether a given high laying bird is 

 of Type I or Type 2. He can only judge of this from her 

 progeny. Experience indicates, however, that about one-half 

 of all high laying birds will fall in one of these types and one- 

 half in the other. It is assumed in the diagrams that each pair 

 of parents will produce 32 off-spring, of which 16 will be males 

 and 16 females. 



The way in which the diagrams are to be read may be illus- 

 trated by a particular example. Let us consider Mating C. 

 We have here the mating of a Type 3 male bird with the high 

 laying flock of females, as indicated by the solid black hen. 

 This mating produces a flock in which nearly all the females 

 (14 out of 16) are high layers. Two out of 16 are mediocre 

 layers (poor winter producers). Three different kinds of male 

 birds are produced from this mating. Six out of the 16 are 

 of Type I, as indicated by the solid black bird, 8 out of 16 

 are of Type 3 like the sire, and 2 out of 16 are Type 7 males, 

 indicated by very narrow bars. Now if a breeder gets from 

 a mating of some particular male with a flock of high laying 

 hens, which he has selected by the use of the trap-nest, a 

 flock which is made up of different sorts of producers in abow^ 



