FERTILIZER CONTROL STATION. 321 



The starch, sugar and fats can pla}' no part in the formation of 

 flesh or the caseine of milk, but are alike in being a source of ani- 

 mal fat and heat. 



Digestibility of feeding stuff's. The composition alone of any feed- 

 ing stuff is a very imperfect standard by which to judge its food 

 value. Of the food consumed by an animal, only that portion which 

 is digested, i. e., that which is dis^^olved by the several digestive fluids 

 and passes into the blood, can serve to maintain the vital functions, 

 or to i)roduce growth. Consequently, certain cattle foods, by being 

 much more digestible than others, are much more completely utilized. 

 The main facts pertaining to digestibility are presented farther on 

 under the head of ^'Digestion Experiments," and the method of ap- 

 plying a knowledge of the composition and digestibility of feeding 

 stuffs is show^n in discussing the feeding experiments. 



XXIII. Timothy hay, from grass grown in Orono, two weeks past bloom, used in 



digestion and feeding experiments. 



XXXIII. Timothy hay, same lot as XXtll. 



XXIV. Clover hay, alsike clover, grown in Orono, mixed with a Timothy, cut 



when partly out of full bloom; used in digeatiun and feeding experi- 

 ments. 

 XXXVII. Clover hay, same lot as XXIV. 



XXVII. Oat straw, from College farm, used in digestion and feeding experiments. 

 XXX. Potatoes, purchased in the market, used in digestion aud leediwj^ experi- 

 ments. 



XXXII Potatoes, same lot as XXX, analyzed after boiling, used in same way. 



XXVIII. Cotton-seed meal, sampled in Lewiston and sent to Station by A. C. 



Chandler, New Gloucester. 



XXXV. Cotton-seed meal, purchased in Bangor for use in feeding experiments. 



XXIX. Linseed meal, sampled at Lewiston and sent to Station by A. C. Chandler, 



New Gloucester. 



XXXIV. Linseed meal, purchased in Bangor for use in feeding experiments. 



XXV. Beef scrap, residue after extraction of the fat by heat and pressure, used 



in feeding experiments. 



XXVI. Pork scrap, residue after extraction of the fat by heat and pressure, used 



in feeding experiments. 



XXXVI. Dried blood, a fine specimen, used in feeding experiments. 



The samples of hay and straw were obtained by chopping very 

 fine from fifty to seventy-five pounds of the material with a hand 

 cutter, mixing the whole thoroughly, and then selecting the portion 

 to be ground for analysis. 



