AUTUMN FRUITS 



plant is a sugar-factory, that it has an income 

 greatly in excess of its expenditure, that it makes 

 very much more sugar than it needs, that some of 

 this surplus overflows in the nectaries of the flowers, 

 and that after the nectaries close up the surplus 

 may be drafted into the fruit. Having got this 

 clearly in our mind, we may go on to say that 

 juicy fruits are well suited for seed-scattering by 

 fruit-eating birds, and that plants with juicy fruits 

 will therefore, in certain conditions, prevail. 



Again, in regard to fruits of the box and pod 

 type, which liberate the seeds by splitting, either 

 gently or explosively, we have to remember that the 

 sides of the box are usually the carpels that is to 

 say, leaves set apart and transformed for the pro- 

 duction of seeds. These carpels, like other leaves, 

 are organs of a limited length of life ; they are likely 

 to die and wither, and crack and shrivel, and fall 

 off like other leaves. Having got this clearly in our 

 mind, we may go on to say that it is very profitable 

 for certain kinds of plants to have box-fruits which 

 open readily to let the seeds out. 



Among the valuable food-stuffs that plants manu- 

 facture, there are three different kinds which we must 

 know. There are fats and oils, as in nuts ; there are 

 sugars and starch (called carbohydrates) ; and, most 

 complex and valuable of all, there are proteins, such 

 as the gluten in wheat. 



Now a big fact about fruits is that they have 

 comparatively little of the more valuable reserve- 

 stuffs. They have comparatively little protein 

 material, but if they are juicy they may have much 



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