8 LESSONS IN POULTRY KEEPING — SECOND SERIES. 



uniformly of an internaediate type, or that desired qualities are always reproduced. In opera- 

 itioii the law " like produces like," is modified, as we shall see, by the tact that It includes the 

 more remote as well as the immediate parents, but, as we shall also see, these modifications of 

 and seeming variations from the law are strictly in accordance with it, and afford no basis 

 whatever for assuming that the law fails to operate in regard to any characteristics or qualities. 



That it often happens that fowls in which some superficial qualities have been improved or 

 intensified by inbreeding have at the same time deteriorated in size, stamina, andproductlve- 

 aiess, no one familiar with the phenomena of breeding poultry would deny. But — as has 

 already been pointed out — it also often happens that size, stamina, and productiveness are 

 ■diminished in fowls that are not inbred. In such cases the explanation given — and It Is the 

 correct explanation — is that lack of size, stamina, and productiveness are due to breeding 

 jfrom birds lacking in these points. They may also be due to external causes, but these need 

 mot be considered here. 



Now if in mating unrelated fowls it is necessary to select for size, stamina, and productive- 

 uress, if we wish to reproduce those qualities in the offspring, it is also necessary to use the 

 same care in selecting for matings of related fowls. And if by selecting for a mat'.ug of 

 unrelated fowls, specimens having the size, stamina, and productiveness we want in their 

 offspring, we, as a rule, get those qualities in the offspring; then if we select in the same way 

 for a mating of related fowls, we may reasonably expect to get offspring like their parents in 

 *hese essential qualities. We not only may reasonably expect to get tbem, but v,e do get them 

 as regularly as we get results in any other kind or class of qualities. And the reason many who 

 ■3nbreed for fancy points, and some who make experiments in inl)reeding, note a loi<8 of " prac- 

 tical" qualities is that they failed, in making their matings,to provide for the retention of those 

 ijualities. 



To cite the available evidence in support of the propositions I have just laid down would 

 ■extend this lesson beyond reasonable limits, but I can assure the reader that every statement I 

 Slave made can be amply supported, and also that if he needs or wants first hand proof he can 

 jeadily obtain it by testing the matter for himself, observing that a proper test requires that the 

 ammediate parents be not deficient in any quality it is desired to have conspicuous In the 

 tprogeny. 



Why Inbreed ? 



So far I have been trying to show that inbreeding is not necessarily a cause of deterioration 

 dn practical or in any otuer qualities, and so to convince the reader that inbreeding is a legiti- 

 tmate and useful means in breeding poultry. Now I want to take the reader one step further 

 rand show him that inbreeding is not merely a method to be considered equally with the practice 

 <of constantly or periodically introducing new blood, but that it is a better method— in fact, the 

 •only method by which high excellence and uniformity can be reached and maintained. 



Reference has been made to the fact that the operation of the law " like produces like," is not 

 (limited to the qualities of the immediate parents, but include also those of more remote ances- 

 rtors. 



According to a law, known as Dalton's law of lieredity, based upon observed facts of 

 (heredity, the general rule is that an individual inherits: 



One-fourth of his qualities from each parent. 



One-sixteenth from each grandparent. 



<»ne sixty-fourth from each great-grandparent. 



•On€ two hundred and fifty-sixth from each great-great-grandpareut. 



An individual has two parents, tour grandparents, eight great-grandparents, sixteen great- 

 -^reat-grand parents. Then 



From 2 ancestors in the first preceding generation he inherits one-half of his qualities and 

 4;baracteri«tics. 



From 4 ancestors in the second preceding generation he inherits one-fourth. 



From 8 ancestors in the third preceding generation he inherits one-eighth. 



From 16 ancestors in the fourth preceding generation be inherits one-sixteenth. 



From 30 ancestors in the four preceding generations he inherits fifteen-sixteenths of hie char- 

 aiffiteristios and qualities, leaving but one-sixteenth of his inheritance to come from the progres- 



