FLOWERS POLLINATED BY THE WIND 



boys together at Carlsruhe, in IS'^T, Braim in one of his letters 

 sent his friend some "nuts to pick," among which was the ques- 

 tion: "Why do some plants blossom before they put forth 

 leaves?" Years before Gilbert White, the naturalist of Sel- 

 borne, had pondered over the same problem. " Why," he writes, 

 "do some plants bloom in the very first dawnings of spring, 

 some at midsummer, and some not till autumn? This cir- 

 cumstance is one of the wonders of creation, little noticed be- 

 cause a common occurrence — but it would be as difficult to be 

 explained as the most stupendous phenomena in nature." 



Difficult as the problem once seemed, there is no longer 

 any mystery why the flowers of many forest-trees appear be- 

 fore their leaves. They are or were in time past pollinated by 

 the wind, although the willows and maples have in com- 

 paratively recent years changed over to insect-pollination. 

 At its best, wind-pollination is a very wasteful method of ob- 

 taining the advantages of cross-fertilization, and much of the 

 pollen falls where it is of no benefit. It would clearly be al- 

 most a total failure in the case of the shrubs and trees enumer- 

 ated, if their branches were covered with a dense foliage which 

 intercepted the pollen. So the flower-buds are formed the 

 preceding season, and begin to bloom in spring just as soon 

 as the weather is warm enough. If Gilbert White were living 

 to-day this phenomenon would excite his astonishment less 

 and his admiration more. 



The common alder is one of the commonest of New England 

 shrubs, growing everywhere in swamps and wet land, and it is 

 also an excellent example of wind-pollination. It blooms early 

 in April, and, where the Mayflower is not found, is the true har- 

 binger of a new season. (Fig. 4.) 



"By the flowing river the alder catkins swing. 

 And the sweet song sparrow cries, 'Spring! it is spring.'" 



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