THE NUTRITIVE VALUE OF CERTAIN FEEDS. 67 



coin meal. It was difficult to induce the animals to eat the shells unground. 

 It was not possible to make any comparative tests of the effect of a defi- 

 nite amount of ground shells upon milk production, as compared with 

 some other grain, for the reason that a sufficient number of animals was 

 not available at the time. The observation simply indicated that the 

 animals would eat the ground shells when mixed with other grain. 



(4) Manurial Value. 

 The average of two analyses of cocoa shells showed them to contain: — 



Per Cent. 

 Nitrogen, . . . . . . . - • ■ ■ .2.45 



Potash. . 2.92 



Phosphoric acid, .......... .69 



The nitrogen was found to be about one-third available. The balance 

 would, of course, be of use to plants from year to year. Based on the 

 above analyses the shells have a commercial value of about $6 a ton as a 

 fertilizer. 



(5) Conclusio7is. 



The results of our study of cocoa shells show them to have a feeding 

 value about one-half as high as corn meal. They are best suited for dairy 

 animals, wliile in foreign countries thej' are used also as a partial food for 

 horses. Dairj^ animals wall, as a rule, not eat them unground. If they 

 can be had at a sufficiently low price the ground shells can be used in 

 amounts of from 1 to 3 pounds daily mixed with the grain ration. 

 Because of their low digestibility it is doubtful if they can be purchased 

 to advantage as a food for horses. As a source of fertility they are evi- 

 dently not worth much more than the cost of cartage and spreading, 

 Thej^ may also be used for bedding purposes. 



4. WHEAT OR GRAIN SCREENINGS. 



Grain screenings consist of the light seed, weed seeds, chaff and dirt 

 separated from grain in the process of winno\ving. The composition of 

 grain screenings depends upon the kind of seed from which they are 

 separated and upon their freedom from dirt and chaff. They necessarily 

 vary so much in composition that no general statement as to their value 

 can be made. Where screenings contain a large amount of straw and 

 chaff they cannot be considered much superior to straw; on the other hand, 

 screenings free from chaff and dirt, and containing nothing but light 

 grain and weed seed, possess considerable feeding value. 



Grain screenings are but little used by themselves as a feeding stuff in 

 Alassachusetts, but are found on the market as a component of molasses 

 feeds, of wheat by-products, and occasionally of the so-called stock feeds. 

 In the west screenings have been used for fattening sheep. Formerly one 



