CH. XVIl] ENTOMOPHILY 163 



The advantage to the flower is, of course, always the 

 conveyance of the pollen to a more or less distant stigma, 

 and in the process of evolution the mutual balance of 

 advantages has worked out much as it would do in an 

 old-established business house : the bee or other insect, 

 attracted by flaming poster, seductive odour, &c., finds 

 honey and pollen accessible, and carries them off. 



But mechanisms in the floral trading house exist 

 which we must look upon as adaptations to prevent waste 

 of pollen, &c., on the one hand, and to so scatter the 

 pollen on the insect that even if he does waste some of it, 

 some is carried to the right spot. 



In the above examples, the role of insects in trans- 

 ferring pollen from one flower to another, or from the 

 stamens to the pistil of the same flower in its hermaphro- 

 dite condition, is fairly simple. The mere wanderings of 

 small flies, bees, &c., among the numerous anthers of a 

 Buttercup, Poppy, or Rose, or among the florets in close 

 spicate, umbellate, or capitulate inflorescences of Plantago, 

 Umbelliferse, Rubiaceae, Dipsacese, Composite, Labiatse 

 and Polygoriese, &c., suffice to ensure an occasional trans- 

 ference and cross-pollination. 



Many flowers, especially those which stand wide 

 open, merely attract various kinds of small insects, by 

 their colour, scent, honey, or pollen, and the creeping of 

 these over the parts ensures both self- and cross-pollina- 

 tion. 



Examples of flowers with no honey, and no very 

 special mechanism are : 



Clematis Elder. 



Examples of flowers with no very special mechanism, 

 but powerfully attractive to insects by their honey and 

 sweet odours, or both, are : 



11 2 



