THE GRASSES OF MAINE. 13 



nitrogen, while the cell walls or cellulose contains only carbon, 

 hydrogen and oxygen. 



As the cells grow older there is a thickening of the walls, and this 

 deposit, which is similar in composition with the original cellulose, 

 has been called lignine. This lignine is an indigestible substance, 

 while a part of the cellulose is capable of being digested. It might 

 therefore happen that many of the cells of the hay would escape 

 being crushed during the process of mastication, and as the diges- 

 tive juices of the animal do not act on the surrounding mass of lig- 

 nine, the albuminoids contained within would escape and be lost to 

 the animal. This view gives weight to the impression that late-cut 

 hay is not as valuable as that which is cut when the grass is just in 

 blossom. 



In the cells of the young and growing parts of a plant, the albumi- 

 noids are present in abundance, but in the older parts they are 

 present in a much smaller proportion because of the increase of the 

 lignine, and also because of the actual transfer of the albuminoids 

 to other parts of the plant, especiallj- to the seeds. In case of the 

 cereals, where the seeds are the most important part, they are allowed 

 to remain growing in the field till this transference to the seeds is 

 completed, but in case of the grasses used for coarse fodder, where 

 all the plant above ground serves for food, the seeds are mostly 

 small and the larger part of them, escaping mastication, pass through 

 the animal undigested, and their contained albuminoids are lost, and 

 since the albuminoids are the most valuable of the food ingredients 

 and the most expensive to produce, it is important to cut and cure 

 the hay at the time when the plant contains the greatest amount, 

 and at the same time when the largest possible proportion of it is in 

 a digestible condition. 



Starchy matter is abundant in plants, and is of value as a food if 

 supplied with a requisite amount of the albuminoids, for while ani- 

 mals can exist on the latter alone, it is impossible for them to exist 

 on starch, since this substance does not furnish the nitrogen neces- 

 sary to build up the tissues. Starch, as well as the fats of the 

 plants, furnish the fat of the body and are of value for fattening 

 animals. 



In the analysis of grasses there is usually given the percentages 

 of water, ash, fat, nitrogen-free extract, crude fiber and albuminoids. 

 The ash contains, among other substances, a large percentage of 

 silica deposited in the substance of the cell walls, particularly those 



