PLANTS AND INSECTS 111 



chamber. The cuculli secrete abundance of nectar, 

 and of a quality which makes insects seek madly 

 after it, The cueulli and the fleshy column are 

 smooth, even slippery, the corolla yielding, so that 

 insects in quest of this nectar find difficulty in re- 

 taining a firm footing-. All the while the insect is 

 clawing the disk and cuculli, never feeling stable, yet 

 acquiring some of the much-coveted sweets. While 

 insects are thus at work, their claws, or the hairs of 

 the tarsi or the tibia, are caught in the \vedge-shaped 

 slit of the corpusculum. If the insect is strong enough, 

 it brings away with it the corpusculum and its two 

 swollen masses, one from each adjoining anther, or it 

 breaks off the ensnared leg in its endeavors to escape. 

 It' the insect is too weak to pull out the pollinia or to 

 sever its connection by breaking the retaining member, 

 it must in consequence die. Such tragedies are not 

 of infrequent occurrence. In case the insect has power 

 to carry away the pollinia, its trouble and dangers are 

 not over, for it will most likely visit another milkweed 

 blossom, where the complementary contrivance awaits it. 

 This slit between the anthers is wider at the bottom 

 for a purpose, and that purpose is to capture the pollin- 

 ium which the insect, has brought from another flower; 

 so the insect, in slipping about again upon this second 

 flower, finds itself fast when the pollinium has entered 

 at the base of the slit. To facilitate this the more, 

 these pollinia when first removed become, upon the dry- 

 ing of the bands or retinacula, twisted inward. This 

 twisting inward of the pollinia enables their entrance to 

 the slit to be made the more readily. When the pollinia 



