FLOWERING AN EXHAUSTIVE PROCESS. 209 



CHAPTER VII. 



OF FLOWERING AND ITS CONSEQUENCES. 



366. PLANTS have thus far been considered only as respects their 

 Organs of Vegetation ; those which essentially constitute the 

 vegetable being, by which it grows, deriving its support from the sur- 

 rounding air and soil, and converting these inorganic materials into 

 its own organized substance. As every additional supply of nour- 

 ishment furnishes materials for the development of new branches, 

 roots, and leaves, thus multiplying both those organs which receive 

 food, and those which assimilate it, it would seem that, apart from 

 accidents, the increase and extension of plants would be limited 

 only by the failure of an adequate supply of nourishment. After 

 a certain period, however, varying in different species, but nearly 

 constant in each, a change ensues, which controls this otherwise 

 indefinite extent of the branches, and is attended with very impor- 

 tant results. A portion of the buds, instead of elongating into 

 branches, are developed in the form of FLOWERS ; and the nour- 

 ishment, which would otherwise contribute to the general increase 

 of the plant, is partially or wholly expended in their production, 

 and in the maturation of the fruit and seeds (110). So far as we 

 know, the sole office of the flower and fruit in the vegetable econ- 

 omy is the production of seed. Hence they are termed ORGANS 

 OF REPRODUCTION (115). 



367. Flowering an Exhaustive Process, Plants begin to bear flow- 

 ers at a nearly determinate period for each species ; which is de- 

 pendent partly upon constitutional causes that we are unable to 

 account for, and partly upon the requisite supply of nutritive mat- 

 ter in their system. For, since the flower and fruit draw largely 

 upon the powers and nourishment of the plant, while they yield 

 nothing in return, fructification is an exhaustive process, and a due 

 accumulation of food is requisite to sustain it.* Annuals flower 



* When the branch of a fruit-tree, which is sterile or does not perfect its 

 blossoms, is ringed or girdled (by the removal of a narrow ring of bark), the 

 elaborated juices, being arrested in their downward course, are accumulated 

 in the branch, which is thus enabled to produce fruit abundantly ; while the 

 shoots that appear below the ring, being fed only by the crude ascending sap, 

 18* 



