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birds, and a good botanist can generally tell by th'e structure of a 

 flower whether it is designed for fertilization through the agency of 

 birds or of insects. The " touch-me-not " and the " cardinal flower" 

 are visited by both humming binls and insects. 



Some of you may have watched a field of grain just after the heads 

 or spikes have become fully developed. Placing the eye nearly on a 

 plane with the heads of grain and looking over its surface early in the 

 day when the breezes begin to play across it, you have seen clouds of 



This dust is the pollen of the flowers ot the grain and the wind is ful- 

 filling its mission as pollen carrier. It is wafting the pollen about in 

 clouds and sprinkling it wholesale upon the feathery stigmas of the 

 blossoming grain. In most of the grasses and cereals the stigmas are 

 plumose and are well adapted by their form and broad surface to catch 

 the pollen as it flies. 



In almost any vegetable garden bumble bees are often to be seen 

 visiting one after another of the large yellow flowers of the squash 

 plants. Their hairy bodies soon become dusted by the copious yellow 

 pollen grains of the staminate flowers and whenever they enter the 

 corolla of a pistillate flower, some of this pollen is sure to be rubbed 

 from their bodies and left upon the stigmas. In this case it is easy 

 to see that pollenization would nor take place without the aid of insects. 

 The corollas are upright and deep, the stamens and pistils are short 

 and situated in the bottom of separate fl6wers. The stamens are 

 therefore sheltered from the wind and only as bees or other insects 

 convey their pollen on their hairy bodies is it ^transferred to the stigmas 

 at all. 



The examples now given serve to illustrate the action of the principal 

 agents in conveying pollen from flower to flower. As already stated, 



agents. It might be interesting here to note some of the more obvious 

 characters which favor one or the other of these agencies. If we find 



pollen. These characters exist in nearly all the sedges, grasses and 

 cereals. Hence they are comparatively independent of insects. We 

 can also see the wisdom of this arrangement in the case of the cereals 



