164 PLANTS OF THE ALPINE MEADOWS 



The inflated calyx certainly adds greatly to the 

 conspicuousness of the flowers. The object of this 

 adaptation is, however, still a debated question. The 

 theory is that the swollen calyx serves to prevent 

 the flower being ''robbed" of its honey. The plant 

 is visited by humble-bees and butterflies. These 

 insects will often try to rob a flower of its honey 

 by biting through the base of the calyx and corolla, 

 instead of entering the flower in the legitimate 

 manner. It is obvious that in such cases the 

 insect can be of no service to the plant in the way 

 of cross-pollination. It is imagined that the inflated 

 calyx in some way protects the plant by making 

 robbery of the honey impossible, or at least more 

 difficult. If this is so, it can only be by deceiving 

 the insect, for the tongue or proboscis of a humble- 

 bee or butterfly is sufficiently long to penetrate both 

 calyx and corolla and the empty space between these 

 organs. It may be that the insect, having bitten 

 through the calyx, is deceived by imagining that the 

 space between the calyx and corolla, where there is 

 no honey, is really the space surrounding the ovary 

 where honey should be found. Finding no honey 

 there, it assumes that some other insect visitor has 

 been beforehand, and thus desists from further efforts. 

 In view of the considerable intelligence possessed 

 by such insects, it is doubtful, however, if so trans- 

 parent a device would prove successful; hence this 

 theory is not above suspicion. 



