30 BOTANY. [chap. i. 



forming the cell-walls, or is re-solidified and stored up 

 for future use. 



The reproductive portion of the plant, i.e., the flower, 

 with all its various accompaniments, is developed for the 

 sole purpose of producing seeds that, under suitable con- 

 ditions, develop into a plant similar to the parent form. 

 The parts of a typical flower, commencing from the out- 

 side, are as follows : — 



(i) Th.6 calyx. Function, protective j usually consists 

 of a ring or whorl of green leaf-like structures called 

 sepals. The use of the calyx being to protect the inner 

 parts of the flower during the bud stage, it usually either 

 falls away or bends back and becomes inconspicuous 

 after the expansion of the flower. 



(2) Corolla. The second whorl of leaves, situated 

 within the calyx or higher up on the axis of the flower. 

 Function, usually attractive to insects in connection with 

 the act of pollination or fertilization. The component 

 parts of the corolla are called petals, and are usually 

 large, coloured, and frequently in addition secrete a 

 semi-liquid saccharine substance that serves as food for 

 insects. The corolla varies much in size, form, and 

 brilliancy of colouring, and is most highly developed in 

 entomophilous or insect fertilized species. 



(3) Stamens. Within the corolla, and consequently 

 situated higher on the floral axis, are to be found a vary- 

 ing number of slender yellow stalks, each terminating 

 in a thickened portion or knob-like head ; these are the 

 stamens, collectively constituting the male element of the 

 flower ; the stalk of the stamen is called the filament, and 

 the knob-like apex, the most important part, is called the 

 anther, which contains the pollen, or fertilizing substance. 



