blossom Hosts and Insect Guests 



We will suppose the bee to be working at the top 

 of the spike. He thrusts his tongue into the nar- 

 row opening (G). The membrane protecting the 

 pollen-gland, thus surely touched, ruptures as de- 

 scribed, and the exposed gland attaches itself to the 

 tongue, being withdrawn as at H, and located on 

 the insect's tongue, as in F, Fig. 4. The bee leaves 

 this flower cluster and flies to another, upon which 

 it will usually begin at the bottom. The flower 

 thus first encountered is an old bloom, as in 

 Fig. 3, D. Its sepals are more spreading, the lip 

 slightly lowered, and the column so changed as to 

 present the plane of the stigma in such a new posi- 

 tion as to invariably receive the pollen. The tongue 

 of a bee entering this flower conveys the pollen 

 directly against the stigmatic surface (I), which re- 

 tains its disentangled fecundating grains, as at J, 

 and the flower's functional adaptations are fulfilled. 

 In the allied spiranthes, or lady's-tresses, a some- 

 what similar mechanism prevails. 



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