How the Flant Grows. 7 



. remaining constituting crude gluten. The nitrogenous portion of 

 beans, peas, clover seeds, etc., is likewise an albuminoid caUed 

 "legumin." 



11. Amides. — The amides are nitrogenous bodies which are 

 crystalline and soluble in water. Being soluble, they can pass 

 through the cell walls of plant tissues, and thus are capable of 



I diffusing from one part of the plant to another. Since the amides 

 ire found in the immature and growing parts of plants, it is 

 probable that their function is the transfer of organized nitrogen 

 from one part of the structure to another in the process of plant 

 building. 



12. Mineral compounds. — Though occurring in relatively small 

 amounts, mineral matter in various combinations is essential to 

 the life and development of all plants. The elaboration of food 

 materials in the protoplasmic masses referred to in the previous 

 paragraph, as weU as the development of the young plants from 

 the seed, require the presence of mineral matter, which is found 

 everywhere in the plant substance. The leaves of plants contain 

 more ash or mineral matter than the other portions. This is 

 probably due to the constant evaporation of water from the 

 leaves, the ash matter in solution beiag left behind. 



13. The end of plant effort. — If we study the life history of 

 an individual plant we observe that its first effort is directed 

 toward self- establishment and enlargement. All of the food 

 elaborated from the compounds taken from air and soil is trans- 

 ferred to the growing parts, that the plant may be built up and 

 reach perfection. As the period of maturity approaches, all the 

 energies of the plant are changed to that of reproduction or mul- 

 tiplication. The food materials, which were at first used for leaf 

 multiplication and enlargement or for the growth of more and 

 larger stems and roots, are now joined iato a current which flows 

 to the reproductive parts. First come the blossoms, and then 

 the young, enlarging fruits. Into these the sugars, protein com- 

 pounds and mineral substances gathered from air and soil, and 

 elaborated in the green parts, are poured in a steady current. 

 The wheat plant resulting from a single kernel bears a hundred 

 fruits in the shape of grains; the Indian corn plant may produce 



