I.] MR. DARWIN'S OBSERVATIONS. 5 



only comparatively of late that we have realised how 

 important, indeed how necessary, insects are to flowers. 

 For it is not too much to say, that if, on the one hand, 

 flowers are in many cases necessary to the existence 

 of insects ; insects, on the other hand, are still more 

 indispensable to the very existence of flowers : 

 that, if insects have been in many cases modified and 

 adapted with a view to obtain honey and pollen from 

 flowers, flowers in their turn owe their scent and 

 colour, their honey, and even their distinctive forms 

 to the action of insects. There has thus been an in- 

 teraction of insects upon flowers, and of flowers upon 

 insects, resulting in the gradual modification of both. 



If it be objected that I am assuming the existence 

 of these gradual modifications, I must reply that it 

 is not here my purpose to discuss the doctrine of 

 Natural Selection. I may, however, remind the 

 reader that Mr. Darwin's theory is based on the 

 following considerations : I. That no two animals or 

 plants in nature are identical in all respects. 2. That 

 the offspring tend to inherit the peculiarities of their 

 parents. 3. That of those which come into existence, 

 only a certain number reach maturity. 4. That those 

 which are, on the whole, best adapted to the circum- 

 stanes in which they are placed, are most likely to 

 leave descendants. 



Now, applying these considerations to flowers ; if 

 it be an advantage to them that they should be visited 

 by insects (and that this is so will presently be shown), 

 then it is obvious that those flowers which, either by 

 their larger size, or brighter colour, or sweeter scent, 

 or greater richness in honey, are most attractive to 



