Fl 



owers 



There are some interesting cases which show how 

 co-operation prevails between leaves and flowers, or 

 even amongst the flowers themselves. 



In the gorgeous Bougainvillea, a great favourite in 

 tropical and sub-tropical gardens, it is the bracts that 

 are flaringly conspicuous, but even more interesting is 

 the common bluebeard salvia of our own borders. A 

 fine dark blue has appeared in the uppermost leaves, 

 which are of course most exposed to the sunshine. 

 The actual flowers are small and provided with light- 

 blue patches and yellow hairs. This is an ingenious 

 effort towards both economy and efficiency, for the 

 flowers are short-lived, whilst the large attractive leaves 

 last during the whole season. 



A tropical orchid (Renanthera Lowii) has a different 

 arrangement. In each spray of flowers the two upper- 

 most are a bright sulphur-yellow with red dots or 

 splashes upon them. These two have a very strong 

 scent and last for a very long time. The other flowers 

 are only white with brown dots ; they have no scent at 

 all, and only live from seven to thirteen days. 



So the attractiveness of the two uppermost answers 

 for all the others.^° 



It is of course to attract insects that these colours 

 and perfumes have been so richly produced in nature. 

 Aided by their own excessive respiration and high tempera- 

 ture, and favoured by the sunshine, petals have formed 

 all these exquisite shades and scents. But they have 

 been from the beginning favoured and guided by the 

 more inquisitive and therefore more intelligent of the 

 insect-world. 



In the gloomy, misty atmosphere of the coal-measure 

 swamp-forests, not very clever insects would surely fly 

 to the yellow spores of the fern-seed plants, and no 

 doubt eat the spores. 



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