ON FLOWERS AND INSECTS. 



[lect. 



shown that if insects have been in some respects 

 modified and adapted with a view to the acquirement of 

 honey and pollen, flowers, on the other hand, owe their 

 scent and honey, their form and colour, to the agency 

 of insects. Thus the lines and bands by which so many 

 flowers are ornamented have reference to the position of 

 the honey ; and it may be observed that these honey- 

 guides are absent in night flowers, where they of course 

 would not show, and would therefore be useless, as for 



Fig. 5.—. 



Fig. 6. — Geranium sylvaticum. 



instance in Lychnis vespertina (Fig. 5) or Silene nutans. 

 Night flowers, moreover, are generally pale ; for instance, 

 Lychnis vespertina is white, while Lychnis diurna, which 

 flowers by day, is red. 



Indeed, it may be laid down as a general rule that 

 those flowers which are not fertilized by insects, as for 

 instance those of the Beech, Oak, and most other forest 

 trees, are small in size, and do not possess either colour, 

 scent, or honey. 



