AN INDIVIDUAL PLANT IN ALL OF ITS KELATIONS 141 



98. Placing of flowers. — The purposes of the flower seem 

 to be served best by exposed positions, and consequently 

 flowers mostly appear at the extremities of stems and 

 branches, a position evidently favorable to pollination and 

 seed dispersal. The flowers thus exposed are very com- 

 monly massed, or, if not, the single flower is apt to be large 

 and conspicuous. The various devices for protecting nec- 

 tar and pollen against too great moisture, and the more 

 delicate structures against chill ; for securing the visits of 

 suitable insects, and warding off unsuitable insects ; and 

 for dispersing the seeds, need not be repeated. 



99. Branch buds. — If the plant under examination be a 

 tree or shrub, branch buds will be observed to be developed 

 during the growing season (see Fig. 65). This device for 

 protecting growing tips through a season of dangerous cold 

 is very familiar to those living in the temperate regions. 

 The internodes do not elongate, hence the leaves overlap ; 

 they develop little or no chlorophyll, and become scales. 

 The protection afforded by these overlapping scales is often 

 increased by the development of hairs, or by the secretion 

 of mucilage or gum. 



