388 FUNDAMENTALS OF AGRICULTURE. 



Fats. The substances called fats are also termed 

 ether extract because they include those parts of feed 

 stuffs which are dissolved out by ether. Oils, fats, 

 waxes, and coloring matters (such as chlorophyll) 

 come under this group. Cotton-seed oil, olive oil, lin- 

 seed oil, butter, hog lard, fish oil, and tallow are ex- 

 amples of fats. 



Nitrogen Free Extract. This is made up principally 

 of the sugars, starches, dextrins and gums. As the 

 name implies, it is free from nitrogen. 



Fiber. The woody parts of plants are called fiber. 

 Cotton lint is almost pure fiber. 



Carbohydrates. This is the name given to the ni- 

 trogen free extract and the fiber, when taken together. 

 These substances are called carbohydrates, because they 

 are compounds of carbon, hydrogen and oxygen. 

 When they are digested by the animal they have the 

 same value, and they satisfy equal demands. 



Water. All feed stuffs, no matter how dry they may 

 appear to be, contain water. The average per cent. 

 of water in feeds such as oats, corn (grain), cotton- 

 seed meal, etc., is about 10 per cent. The green grasses 

 contain about 80 per cent, of water, and root crops 

 carry about 90 per cent, of water. 



Classification. The following statement gives the 

 parts of plants (feed stuffs) in a condensed form: 



Pree 



Carbohydrates \ Extract 

 I Fiber 



Composition of Feed Stuffs. The composition of 

 feed stuffs (plants and grains) may be expressed as 

 follows : 



Protein Fiber 



Fats (Ether Extract) Water 



Nitrogen Free Extract Ash 



EXERCISE. Take one pound of green grass and dry it in the sun. 

 What is the loss in weight? What is this loss in weight due to? 



Have some pupils bring grains of corn and Irish potatoes to the 

 classroom. Purchase five cents' worth of tincture of iodine at any 



