158 (;iJMrsEs ixTO pi.ast-life 



flower beins^ the small inconspicuous blossom in 

 the centre. 



In the chapter on leaves we saw that bracts are 

 those small imperfecth'-shapecl leax'cs in the axils 

 of which flowers are placed. They are usually 

 green, but may be also brilliantly tinted as in the 

 mauve-coloured Bougainvillia, the bright violet 

 spikes of the Salvia Hormincwii, and also pure 

 white as in the s[)athe of the arum. 



liy special cultixation flowers can be made 

 double, for excess of nourishment will cause the 

 jjlant to n^iultiply its petals. Instead of the five 

 pink petals of the wild rose we find one of our 

 garden roses bearing as many as eighty or a 

 hundred petals. 



Double flowers but rarely produce seeds, because 

 the stamens and pistil ha\e been turned into petals, 

 and as there is no need to attract insects for 

 fertilising purposes, there is no secretion of hone)', 

 and therefore we scarcely e\er see hone)'-bees in 

 double flowers ; they are wise enough to know 

 that their visits to them would be in vain. 



In composite flowers such as asters and sun- 

 flowers the change, when they are double, occurs 

 in several ways. 



