146 SELECTION. 



such animals, and rear these, or cross with the native 

 stock, and during this whole time a process of selec- 

 tion for uses is going on by all alike, — the cow 

 giving the most milk being retained, while the poorer 

 milker finds her place in the shambles. The progeny 

 of the largest milking animal is reared, in preference 

 to others whose ancestors are not so well, or unfavor- 

 ably, known for this quality. The fashion and the 

 natural eagemiess to secure those colors which are 

 attractive, also come into play ; while the improved 

 system of farming, the enclosing of lands, the winter 

 protection, and other adjuncts of improved agricul- 

 ture, aided in bringing the breed to a larger size and 

 greater excellence. 



It is possible that the Guernsey breed may have 

 transmitted some of her quality to the present Ayr- 

 shire, as is suggested by the sandy red and pied 

 Dunlop ; but if so, it is scarcely ever shown at pres- 

 ent in color of skin or hair. Similarity of function 

 can produce a certain similarity in form ; and what- 

 ever resemblance may exist between the Alderney 

 and the Ayrshire can well be referred to this law. 

 We find a correlation between the external parts of 

 a cow and her physiological functions ; and two sep- 

 arate peoples, seeking in a breed dairy qualities, 

 would naturally and unavoidably obtain certain shapes 

 in common, from whatever breed they may have ori- 

 ginally started. It is in the point where differentia- 

 tion occurs that we would look for divergence, and 

 we see it in the udder : the one breed designed for 

 butter alone, the shape of the udder is neglected in 



