II.] THE SCENT OF FLOWERS. 43 



certain plants produce no seeds at all, unless visited by 

 insects. Thus, in some of our colonies, the common 

 Red Clover sets no seeds, on account of the absence 

 of humble bees ; for the proboscis of the hive bee is 

 not long enough to effect the object. According to 

 Mr. Belt, the same is the case, and for the same reason, 

 in Nicaragua, with the scarlet-runner. But even in 

 those instances in which it is not absolutely necessary, 

 it is an advantage that the flowers should be fertilised 

 by pollen brought from a different stock, and with 

 this object in view insects are tempted to visit flowers 

 for the sake of the honey and pollen ; while the 

 colours and scents are useful in making the flowers 

 more easy to find. 



Fortunately for us, bees like the same odours as we 

 do ; and as the great majority of flowers are adapted 

 for bees, they are consequently sweet ; but it might 

 have been otherwise, for flies, as already mentioned, 

 prefer unpleasant smells, such as those of decaying 

 meat, and other animal substances on which they 

 live as larvae, and some flowers, consequently, which 

 are fertilised by them are characterised by very evil 

 odours. Colours also are affected in the same man- 

 ner, for while bee-flowers (if I may coin such an 

 expression) have generally bright, clear colours, fly- 

 flowers are usually reddish or yellowish brown. 



Nevertheless although flowers present us with these 

 beautiful and complex contrivances, whereby the 

 transfer of pollen from flower to flower is provided for, 

 and waste is prevented, yet they appear to be imperfect, 

 or at least not yet perfect in their adaptations. Many 

 small insects obtain access to flowers and rob them of 



