THE WELCOMES OF THE FLOWERS 13! 



back. Having backed out of this segment of the 

 blossom (A, Fig. 7), he proceeds to the next ; but 

 the shelf-like stigma awaits him at the door, and 

 scrapes off or rubs off a few grains of the pollen 



Fig. 7 



from his back (B). Thus he continues until the 

 third segment is reached, from which he carries 

 away a fresh load of pollen to another flower. It 

 will be seen that only the outer side of this ap- 

 pendage is stigmatic, and that it is thus naturally 

 impossible for the blue-flag to self-fertilize only 



