12 BOARD OF AGRICULTURE. [Pub. Doc. 



explanation of the way in which factors combine. Enough 

 has been said to show tliat the transmission of characters 

 from one generation to another is an orderly process, even 

 if it is complex and hard to understand. 



The dairy cow, as we see her, is the visible result of 

 all these invisible processes that we have been discussing. 

 We may judge somewhat of what has taken place in the 

 colls of the parents by the characters visible in the mature 

 cow. A study of her ancestors will tell us something more 

 of what we may expect from her offspring. Galton, in 

 England, reports the results of the study of a large nimiber 

 of Basset hounds.^ From a careful record kept of the coat 

 colors of these hounds it was found that the two immediate 

 parents dominated in the color of one-half their offspring, 

 that the grandparents dominated one-quarter, the great 

 grandparents one-eighth, and so on. Of course this must be 

 considered merely as a general law, and will work out only 

 in practice, when large numbers are considered. Other 

 factors, such as prepotency, vigor and dominance may modify 

 the results. 



As a working basis for determining the value of any par- 

 ticular ancestor it will be found approximately correct. For 

 instance, if one ancestor in the great-grandparent row was 

 possessed of exceptionally good qualities, what is the chance 

 of these qualities appearing in the great-grandchildren ? The 

 two parents contribute 50 per cent, the 4 grandparents 25 

 per cent, and the 8 great-grandparents 12l/o per cent of 

 the general characters. Any one great-grandparent, there- 

 fore, will only contribute on the average one-eighth of 121/^ 

 per cent, or a little over IV2 per cent. 



This gives a rather poor chance upon which to buy or 

 select breeding stock. If all the ancestors are good, then 

 the different generations may be added together, giving a 

 chance for good offspring of 50 or 75 per cent, or even 

 greater. 



Even if we are given good sires and dams with which to 

 work the offspring will not all be good. The back ancestors 



» Proceedings of the Royal Society, LXI., 401-412. 



