Packard] LN SECTS OF THE FIELD. 201 



same branch, which were not so treated, retained their fresh- 

 ness." Now, as we have said, the great agencies in nature 

 in performing this act of cross fertilization are llie wind and 

 insects, principally the latter. The stamens and pistils of 

 the pines, birches, poplars, grasses, corn and other cereals 

 are so arranged that the Avind fertilizes them, but in a largo 

 nnmber of flowers the stamens are so situated in relation to 

 the pistils, that the ovule in the latter can only bo fertilized 

 by the agency of insects. For this end the plant must hold 

 out some inducement to the bees and moths, in order to 

 attract them, something besides bright colors and sweet 

 smells, which are known to attract insects. "Flowers, how- 

 ever sweet-smelling or beautiful, would not be visited by 

 insects unless they had some inducements more substantial 

 to offer. These advantages are the pollen and the honey ; 

 although it has been suggested that some flowers beguile 

 insects hy holding out the expectation of honey which does 

 not really exist, just as some animals repel their enemies by 

 rcseml)ling other species which are either dangerous or disa- 

 greeable." 



That many insects arc attracted b}' smells wg well know, 

 but Lubbock has been the flrst to show that bees and wasps 

 are attracted by and can distinguish colors. "I placed," 

 he says, "slips of glass Avith honey, on paper of various 

 colours, accustoming different bees to visit special colours, 

 and when they had made a few visits to honey on paper of a 

 particular colour, I found that if the papers were transposed 

 the bees followed the colour." 



The bright streaks of different hues which adorn the 

 petals of flowers serve the most utilitarian purpose ; namely, 

 as guiding lines to show the bee the way down to the 

 deposit of honey. At figure 151, </ indicates the bright col- 

 ored guiding lines which lead down to the nectary. Lub- 

 bock remarks that he did not realize the importance of these 

 guiding lines until, by experiments on bees, he saw how 



9 



