62 THE JERSEY, ALDERNEY AND GUERNSEY COW. 



Up in some other form, they are very readily trans- 

 formed into the elements of milk, from the system hav- 

 ing become long habituated to the peculiar changes 

 essential in this process. Accordingly, some good 

 milkers, and particularly old cows in which vital activity 

 is constantly decreasing and systemic reaction becom- 

 ing progressively more and more difficult, acquire a 

 sickly appearance, the defective lymph is deposited in 

 the form of the masses of tubercular matter so con- 

 stantly found in the chest of old cows, the animals be- 

 come phthisical, the organs of procreation become 

 unhealthy, and with more or less constant irritation of 

 the ovaries the cow becomes barren. With this irrita- 

 tion there is a periodic check to the secretion of milk ; 

 nevertheless a very considerable flow continues, not- 

 withstanding the obvious waste of every tissue in the 

 animal's body. 



The fact that the system is more capable of under- 

 going natural, though very marked, changes in early 

 life without danger, renders a young animal indispen- 

 sable for the dairy, either to breed from or to prove 

 profitable to the town cow keeper. 



To DETERMINE THE AGE OF A COW is therefore a matter 

 of importance, and this can be done with great precision 

 by examining the teeth and horns. 



The horns do not furnish us with such certain indi- 

 cations as the teeth, and great facilities are offered in 

 some animals to destroy the marks of growth and age. 



According to the breed does the length, thickness, 



