POLLINA TION. 



449 



the finger, and luucli the upper surface of the labellum by thrusting it 

 between the latter and tlie ^tyle. The labellum curves quickly downward. 



866. Sometime^ the bLimblebec>, after sipping the nectar, will crawl up 

 over the style in a blundering manner. In this way the flower nia\- be pol- 



r^-A 





'K^ -v > e 



Fig. 471- 

 Polliimtion of the canna flower by bumblebee. 



Canna flower. Pollen on style, sta- 

 men at left. 



linated with its own pollen, which is equiv.ilent to self pollination. Un. 

 doubtedly self pollination does take place often in flowers which are adapted, 

 to a greater or less degree, for cross pollination by insects. 



