278 THE WONDER OF LIFE 



and of subsequent evolution. The answer to the question 

 of the origin of substances of sweet odour is to be found 

 in the physiological study of the plant. But the 

 subsequent success of flowering plants with particular 

 odours may have been due to the fact that these odours 

 attracted useful insect visitors and repelled intruders. 

 There is no doubt that bees are attracted by the fragrance 

 of honey and of certain flowers. Bouvier quotes the 

 pretty observation of Perez that bees frequenting the 

 willow catkins in the early Spring are always to be seen 

 coming from the side toward which the wind blows the 

 fragrance. 



Thirdly, there is the question in regard to colour, which 

 is the most difficult of the three. For while it is certain 

 that bees like sweetness, and that bees like certain odours, 

 it does not seem so certain as was once supposed, that bees 

 like particular colours. There are some difficulties. Bon- 

 nier put a row of painted blocks red, green, white or 

 yellow on the turf near some hives and baited each with 

 honey. They were visited impartially by the bees, but 

 with a slight preference for green. It is said, however, 

 that when bees are preoccupied with flower-visiting they 

 do not pay much heed to other things. It must also be 

 remembered that the flower is to the bee a complex of 

 sensations appealing to sight and smell and taste ; and 

 that in trying to get at the truth by analysis one may land 

 in fallacy. 



Forel put coloured artificial flowers in a basket of dahlias 

 and baited them with honey. The bees kept to the dahlia 

 till an inquisitive or blundering individual discovered the 

 treasure in the artificial flowers. These were then thor- 

 oughly explored, except the green ones. Even after the 



