CHAPTER XI 

 BEETLES AND FLOWERS 



THERE are no beetle-flowers, although Delpino believed 

 that the flowers of magnolia were adapted to flower- 

 beetles of the genus Cetonia. It would be much better, 

 indeed, for flowers if they were never visited by beetles, for they 

 accomplish far more harm than benefit. As agents in pollina- 

 tion they are of little significance. The enormous devastation 

 of foliage and bloom, the absence of hairs for holding pollen, 

 the consumption and waste of pollen and nectar, the inactivity 

 of many species, and their indefinite manner of flight are factors 

 which greatly reduce their value as pollen-carriers. As a whole 

 they are highly destructive to vegetation and cause annually 

 much loss to the farmer, fruit-grower, and florist. The cherry- 

 weevil often destroys the crop of plums and cherries, the rose- 

 chafer strips the rose-bushes of both flowers and foliage, while 

 the blister-beetles may devour large areas of tomatoes and 

 potatoes in a few days. 



But the order of Coleoptera, or beetles, is of special interest, 

 as Mueller has pointed out, because it shows so clearly how the 

 habit of anthophily, or flower-visiting, has arisen, and its be- 

 ginnings in many different families, genera, and species. The 

 length of time which has elapsed since the first tendency in a 

 family toward this habit was manifested is indicated by the 

 number of species which resort to flowers. Where a whole 

 family is dependent on a floral diet the epoch was more remote, 

 but where there are only a few isolated species the habit has 

 been acquired more recently. In the most diverse families 



178 



