148 FERTILIZATION. 



The water is exhaled with the rest ; the cellulose is retained to incrust 

 a new cell as soon as the primordial utricle shall next divide itself to 

 form one. Or it may be deposited as starch granules for future use. 



747. ACTION OF CHLOROPHYLLE. In the cells of green plants the 

 globules of chlorophylle act an important part. Their formation de- 

 pends upon the decomposition of carbonic acid (C0 2 ), the retention of 

 the carbon, and the exhalation of the oxygen under the stimulus of the 

 light. If the formation of cellulose continue beyond the present need 

 for cell-formation, the excess is deposited in the form of starch-granules 

 inclosed within the globules of chlorophylle, one in each. 



748. DESTINATION OP THE STARCH GRANULES. When the starch granules are 

 redissolved, they go to incrust the next new cell or to form a secondary layer in the 

 old cell ; or in autumn they go out into the general circulation and are at length 

 stored up in the buds, the cambium, the roots, ready for an early use the following 

 spring, 



749. THE INCREASE OF THE PROTOPLASM from the decomposition of 

 the ammonia or other nitrogenous compounds present is a more in- 

 tricate process, but no less evident, and when in excess, this also is de- 

 posited in minute globules of gluten, mucus, legumine, chiefly in seeds 

 (wheat, beans, rice), in aid of germination. 



750. THE STARCH AND GLUTEN DEPOSITS of the wheat kernel are about sixty- 

 eight and seventeen per cent. The former is found in the interior cells, the latter 

 in the exterior, adjoining the pericarp or bran. In " flouring" some of the gluten 

 adheres to the bran, and some constitutes the coarser meal, all of which is separated 

 by the " bolt." Extra flour must, therefore, necessarily be deficient in gluten, the 

 only element of the wheat which adapts it to the formation of muscle. A great error. 



FERTILIZATION. 



751. CAPACITY OF THE CELL. Such being the vital energy of the 

 cell, it is easy to admit the possibility of either its solitary existence as 

 a plant (Protococcus, etc.), or of its associated existence, as in the living 

 tissue of most plants. 



752. Two MODES OF CELL-GROWTH. Now all plants, without excep- 

 tion, do actually commence existence in the state of a simple cell. But 

 while in the lower plants (Cryptogamia), this simple cell, the plant- 

 rudiment is at once discharged, free and independent, to float or grow, 

 in the Phenogamia it is yet a while protected and nourished by other 

 cells, the cells of the ovule. 



753. A DISTINCTION. This primitive cell-plant, after acquiring the 

 requisite means, swells and divides itself into two or more new cells. 

 If these new cells cohere into a tissue assuming a definite form, as in 



