334 



ANIMAL BIOLOGY 



the field, the pollen combs are first brought into play to comb the 

 pollen from the hairs, while the pectens scrape the pollen from 

 the combs. Then the auricles are manipulated so that the ac- 

 cumulating mass of pollen is pushed up into the bristle-covered 

 pollen baskets. This process is repeated until the baskets are full 

 and then the insect returns to the hive, where the contents of the 



Fig. 219. — Pollination of an Orchid, Cypripedium, by a Bumble Bee. 

 A, Bee forcing its way into the flower; B, Bee obtaining nectar in the flower; 

 C, Bee starting to escape brushes pollen upon the stigma of the flower; D, be- 

 fore finally escaping the Bee receives another load of pollen from the anther. 



pollen baskets are removed by the aid of the spurs with which the 

 mesothoracic legs are provided. (Figs. 218, 219.) 



Moreover, the structural adaptations of the worker Bee are but 

 one aspect of a reciprocal fitness. Many of the flowers which the 

 Bee visits show remarkable adaptations for the reception of the 

 Bee and for dusting it with pollen, because Bees are effective 

 agents in transferring pollen from flower to flower and thus insur- 



