266 



ENTOMOLOGY 



FIG. 259. 



flower which though entomophilous in general structure has 

 apparently adapted itself in no way to the single insect upon 

 which it is dependent for the continuance of its existence. More 

 than this, the insect not only labors without compensation in the 

 way of food, but has even become highly modified with, refer- 

 ence to the needs of the plant, its special modifications being 

 unparalleled among insects with the exception of bees, and 

 being more puzzling than the more extensive adaptations of 

 the bees when we take into consideration the impersonal nature 

 of the operations of Pronuba. Further investigation may 

 render these extraordinary interrelations more intelligible, or 

 less mysterious, than they are at present. 



The bogus Yucca moth 

 (Prodo.i'its (jiiiiujucpnnc- 

 tella) closely resembles 

 and associates with Pro- 

 nuba but oviposits in the 

 flower stalks of Yucca 

 and has none of the spe- 

 cial adaptive structures 

 found in Pronuba. 



As regards floral adap- 

 tations, these examples 

 are sufficient for present 

 purposes ; many others 

 have been described by 

 the botanist; in fact, the 

 adaptations for cross pol- 

 lination by insects are as 

 varied as the flowers them- 

 selves. 



Insect Pollenizers. The great majority of entomophilous 

 flowers are pollenized by bees of various kinds; the apple, 

 pear, blackberry, raspberry and many other rosaceous plants 

 depend chiefly upon the honey bee, while clover cannot set seed 

 without the aid-of bumble bees or honey bees, assisted possibly 



Phlegethontius sexta visiting flower of Petunia 

 Reduced. 



