FOODS ANIMAL PRODUCTION. 



0«1 



crop, contain (to the end of the season) a small proportion of nonalbuminoids, but 

 not enough to keep au excess in the stalks, which, as a consequence, lose nearly all 

 their nonalbuminoids after the flowering period." 



Noiialbuminoid nitrogenous materials are easily soluble in water or 

 dilute reagents. Many of the albuminoids, however, are insoluble. 

 The proportion of soluble and insoluble albuminoids in alfalfa was 

 determined by digesting samples with a dilute solution of pepsin and 

 hydrochloric acid. 



"In the whole plant the percentage of protein insoluble in pepsin decreases until 

 budding time. It then remains constant for i weeks, or until the first week of full 

 flower. It then falls agaiu, but remains practically constant until the end of the 

 experiment. . . The reason the percentage of pepsin-insoluble protein in the whole 

 plant decreases as the plant grows older is easily understood when we recall that 

 the ratio between the leaves aud stalks is not constant, but widens as growth goes 

 on. When, therefore, the plant is young and the leaves are abundant, the percent- 

 age of pepsin-insoluble protein is high. As the plant grows older, and the stalks 

 increase more rapidly than the leaves, the percentage of the pepsin-insoluble pro- 

 tein is smaller." 



The nuclein was determined in the plant, leaves, and stalks of alfalfa 

 and other hays cut in 1897, and in wheat, peas, and alfalfa seed. The 

 results obtained were as follows: 



Nuclein in alfalfa and other plants and seeds. 



Substance. 



Alfalfa second crop, young. 



Alfalfa, first crop, old 



Clover slightly spoiled 



Timothy, slightly spoiled... 



Wheat, very young 



W heat, ripe 



Oats, very young 



Oats, ripe 



Wheat, 3 years old 



Wheat, 1 year old 



Peas 



Altalfa 



Leaves. 



Per cent. 

 6.78 

 6.8fc 

 9.62 

 3.15 

 4.04 

 3.90 

 3.48 

 3.46 



Stalks. 



Per cent. 

 2.93 

 2.32 

 2.71 

 1.10 

 1.55 



1.58 

 1.29 



Seeds. 



Per cent. 



1.35 

 1.28 

 1.62 

 7.13 



"The results, taken in connection with those previously given, furnish sufficient 

 evidence that the percentages of nuclein in the leaves and the stalks of alfalfa are 

 invariable; that they are not affected by the age of the plant, by the season, or by 

 the place of cutting. They show further that the leaves and stalks of other plants 

 do not contain the same percentages of nuclein as alfalfa, though the percentages 

 they do contain are constant. The constancy does not seem to he confined to leaves 

 and stalks alone, for 2 samples of wheat seed, grown in different years, contain the 

 same percentage of nuclein. Only one sample of clover was obtained, aud that in 

 an imperfect condition ; the analysis can not therefore be depended on to show the 

 truth for a perfect sample. 



"The wheat contains little more than one-half as much nuclein as alfalfa, the 

 oats contain about half as much, and the timothy less than one half. . . . 



"With these results in our possession, and until later work shall modify them, it 

 may be stated as a law that each organ of a plant contains a definite and invariable 

 percentage of nuclein which is different from that of any other organ, and that sim- 

 ilar organs of different plants do not necessarily contain the same percentages of 

 uuclein." 



