272 STUDIES IN SEEDS AND FRUITS 



a contrast between a moist living fruit that has yet to dry and a fruit 

 that has more or less completed the drying process and is to a greater 

 or less degree devitalised (p. 260). 



(5) The tabulated results of the author's observations on the drying 

 of fruits in air indicate that nature does not recognise this distinction 

 betwreen moist and dry fruits, all matureliving fruits being moist fruits. 

 The contrast which the systematist draws between the fleshy drupe of 

 Prunus and the dehiscing, dried, or drying fruit of Datura is not the 

 contrast nature offers. Nature as interpreted through the balance tells 

 us that the full-grown moist and living capsule of Datura Stramonium 

 contains just as much water as the ripe drupe of Prunus communis, and 

 that the dried and dead open capsule of the one could only be 

 compared with the dead and shrivelled drupe of the other (p. 261). 



(6) These misconceptions lead to others. Thus, it is usually 

 implied that dry dehiscent fruits, like typical capsules and legumes, open 

 only when they are ripe, an assumption that involves us in much 

 confusion between the maturing, dehiscing, and drying stages of fruits. 

 How much we may err in this respect is indicated in Chapter XIII, 

 where it is also shown that ripe capsules and ripe legumes are all moist 

 fruits as far as their water-contents are concerned, and that whilst the 

 capsule dehisces in the living, moist state, the legume opens in the dried 

 and dying condition (p. 262). 



(7) Amongst the points brought out in the tables are the large amount 

 of water in full-grown, living, woody fruits, and the manner in which the 

 drying of fruits is retarded by the presence of sugars and oils (p. 265). 



(8) Some curious considerations also arise from the fact that 

 immature fruits contain more water than mature fruits. But this 

 progressive change in the water-contents as the fruit passes from 

 immaturity, when it contains, we will say, 80 per cent, of water, to 

 maturity, when the amount would be about 70 per cent., and thence 

 on to the drying stage accompanying its loss of vitality, when it retains 

 only the water of hygroscopicity, probably about 15 per cent., is 

 characteristic of all vegetable matter (p. 267). 



(9) At first during active life this decrease is only relative' and is 

 due to the more rapid increase of the solids. In the latter stage, when 

 the plant dies, it is absolute and involves the loss of all the water 

 required for the active processes of vitality. The occasional vivipary 

 of the acorn on the Oak and of the seeds of the Ivy berry [Hedera) on 

 the plant is in part an expression of the principle that the mature fruit 

 contains less water than the immature fruit (p. 269). 



(10) The increase in the solid constituents of a growing fruit as 

 the water-contents decrease is well brought out in the tables, in one 

 table for a variety of fruits, in another with special detail for the acorn 

 and the Ivy berry (p. 270). 



