Flowers. 



195 



Fig. 1 10. 



Photograph of a Cabbage Butterfly caught by 

 its legs in the corpuscula of two Asclepias 

 flowers and unable to escape. 



chamber, they put forth pollen tubes which penetrate to 



the tips of the st)ies, 



and then turn down- 

 ward and find their way 



to the ovules. 



A useful insect is 



rarely held in captivity 



by the flower, while 



weak insects, or their 



legs which have been 



pulled off in their strug- 

 gle to free themselves, 



are often found hanging 



to corpuscula that have 



not been removed from 



their original places. 



Figures no and in illustrate instances of this kind. 

 Rarely, indeed, a honey bee, too eager in its search 



for nectar, becomes caught 

 in many flowers at once, and 

 is unable to extricate itself 

 (Fig. 112). 



Figure 113 is a photo- 

 micrograph of a pair of 

 pollinia attached to their 

 common corpusculum, and 

 Figure 114 is a photograph 

 of a bee's leg with four 

 corpuscula and two pollinia 

 attached. There the second 

 corpusculum has caught on 

 one arm from the first, and 

 so on. 



Fig. III. 

 Photograph of a Moth with its legs 

 caught in the corpuscula of three 

 Asdepias flowers, one leg having 

 been pulled off in its vain efforts to 

 extract the pollinia and escape. 



