VEGETABLES. 



99 



while the amount of fat is small but varies considerably. In order 

 therefore to get the required amount of nutritive material from a 

 purely vegetable diet, it is necessary to consume a much greater 

 quantity, and the amount of excrement indicating the indigestible 

 matters is proportionately increased. 



Cereals. The most valuable forms of vegetable food are those 

 obtained from the seeds of certain kindred plants (Graminacece), 

 wheat, rye, maize, oats, rice, etc., which when ground are used 

 either as "whole meal," or, the integument ("bran") being re- 

 moved, as flour. They contain different kinds of proteid. (1.) A 

 native albumin soluble in water and coagulable by heat, and in 

 many respects like animal albumin ; but as it cannot be obtained 



Section of Pea, showing starch and aleurone granules imbedded in the 

 protoplasm of the cells. (After Sachs.) a, Aleurone granules, st. Starch 

 granules, i. Intercellular spaces. 



pure it is imperfectly known. (2.) Vegetable fibrin, an elastic 

 body, which coagulates spontaneously and is difficult to separate. 

 (3.) Vegetable glue or gliadiu, which gives the peculiar adhesive- 

 ness to the gluten, as the proteid mixture obtainable from corn is 

 commonly called. Cereals also contain traces of fat, and a very 

 large proportion of starch and some salts. 



The following table gives the percentages of the chief different 

 nutritive stuffs in some common cereals: 



