AUTUMN FRUITS 273 



insistence on the survival-value of the bursting of box- 

 fruits that should come second. 



When we inquire into the chemistry of fruits one big 

 fact stands out clearly, that they have relatively little of 

 the more valuable reserve-stuffs. They have relatively 

 little proteid material, but if they are succulent they may 

 have much water and sugar. Seeds, on the other hand, 

 are rich in proteids, and the advantageousness of this is 

 plain, when we recognise that what is spent in the fruit 

 is lost, while what is stored in the seeds is legacy. Apart 

 from the seeds, it is said that it requires i Ib. of grapes, 

 2 Ib. of strawberries, 2j Ib. of apples, and 4 Ib. of pears to 

 furnish as much proteid as there is in one egg. 



In the ripening of the fruit many interesting chemical 

 changes go on. There are fermentations, for instance, 

 such as that which changes the starch of the unripe fruit 

 into the sugar of the ripe fruit, or that which changes pectose 

 into pectin. There is the appearance of pigments, such as 

 the anthocyanin of the rosy-cheeked apple, which is the 

 same as the red of the withering leaf and of some flowers. 

 There is also the formation of ethers and oils and other 

 subtle compounds, some of which are aromatic, giving the 

 fruit a fragrance which is sometimes even finer than that 

 of the flower. 



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