204 INHERITANCE. 



Those features of animal form that are readily 

 cognizable, are usually more changed through the 

 breeder's art, than other features which are not so 

 readily noted. Consequently, the grazing breeds 

 have been brought to a greater uniformity and per- 

 fection, than have the dairy breeds, as the changes 

 to be desired have been more clearly indicated in 

 the be<?innin2:, and recognized in the achievement. 

 Changes in the dairy breeds are to be understand- 

 ingly brought about by breeders and farmers, who 

 have a practical belief in the universality of law, — 

 that inheritance of form is not more important in 

 modifying the shape of body than it is in determining 

 the product from the animal. 



Wiicther a cow's milli is better fitted for the mak- 

 ing of butter or cheese, or for any other purpose, is 

 largely determined by inheritance ; as is also the 

 amount she will give, the manner in which she will 

 give it, the economy with which she will produce it 

 from her food, and the effect of the production upon 

 the health of the animal. 



Milk is the product of the mammary gland, and is 

 a fluid intended for the nourishment of the infant 

 animal. It contains, therefore, all the elements 

 needed for development and growth, and, chemi- 

 cally, is thus a perfect food. 



The milk-glands, whose mammae or teats furnish 

 the name to the class Mammalia of naturalists, are 

 four in number, in the cow, and, united by envelop- 

 ino' tissues, form the vessel called the udder. This 

 organ occupies the posterior j)ortion of the al)domen. 



