32 FEEDING ANIMALS. 



and some fatty matters. If the milky liquid which passes 

 through the muslin is allowed to stand undisturbed for a 

 little time, all the starch will settle to the bottom of the 

 tumbler, and the liquid above will be quite clear, and may 

 be drawn off. On boiling this clear liquid, white, volum- 

 inous flakes of vegetable albumen (a substance similar to 

 the white of eggs) will separate. After removing the al- 

 bumen and evaporating the liquid, a little sugar and gum 

 will be found. Thus starch, sugar, gum, fat, gluten, albu- 

 men, and salts are found in wheat. In Indian corn, rye, 

 and barley these constituents will be found nearly the 

 same ; but in oats, peas, beans, etc., instead of gluten and 

 albumen, will be found a substance which resembles, in 

 nearly all chemical characteristics, casein of the curd of 

 milk. This substance, having first been found in legumi- 

 nous plants, is called legumen, and is so near like casein as 

 to be called vegetable casein. 



The most of the table on opposite page is taken from 

 analyses by Eitthausen. 



Chemists have also found certain nitrogenous organic 

 substances in the grasses and other vegetables, having some 

 chemical resemblance to ammonia called amides. But a 

 separate discussion of these is not important, since in 

 analyses these are included in the total amount of nitrogen 

 in the plant. 



The term protein is now largely used by chemists to 

 mean all the albuminoids collectively. As will be seen by 

 the above table, all these substances contain about 16 per 

 cent, of nitrogen, and small quantities of sulphur or phos- 

 phorus, or both. It will be noted that the percentage of 

 nitrogen is substantially the .same in these vegetable sub- 

 stances as in animal albumen, casein, and fibrin, and they 

 can hardly be distinguished from each other. Therefore 

 we see that the material of which the flesh and blood of 

 animals principally consist, exist ready-formed in the 



