146 IN THE GUIANA FOREST. 



it not bring up the old memories ? What a close 

 resemblance ! " Your enthusiasm carries you 

 away, and you expect an eager response. But 

 no, not a word does he say, although his politeness 

 prevents him from contradicting you. The fact is 

 the flower has already done its work for the day, 

 and not the slightest trace of perfume lingers on 

 its beautiful petals. 



This is by no means uncommon, in fact, inter- 

 mittent distillation is almost general in the white 

 flowers of the tropics. Even in temperate climates 

 there is a striking difference between the amount 

 of perfume given out at different times, but rarely 

 are the flowers quite scentless at any time. It 

 might be thought at first that these alternations 

 were erratic, but close observation shows that they 

 are nearly true to the minute, and if carefully 

 timed would almost certainly be found to coincide 

 with the period when the fertilising agent is on 

 the wing. For this is the simple explanation ; the 

 flower can only be fertilised by a particular kind 

 of insect, and all its efforts are put forth when that 

 insect is likely to be hovering around. Without 

 the flowers the bee could not exist, and without 

 the bee no seed would be produced. That this 

 interdependence is complete can be easily proved 

 in our gardens, as indeed it is also patent to every 



