308 



LECTURE XIV. 



consumed, in the unripe seeds, is less than one. More oxygen is taken up 

 than is given off as carbon dioxide. During ripening the ratio becomes 

 greater than one, only to fall below one again after the fruit has become 

 completely ripe. Analogous results have been observed in the ripening of 

 olives, which in their unripe condition contain mannitol. The following 

 figures published by A. Roussille 1 will give us an idea of the process which 

 accompanies the ripening of olives: 



Leclerc du Sablon 2 found the following amounts of carbohydrates and 

 fats in nuts per 100 parts of the dry substance: 



The changes of carbohydrates into fat in the almonds were as follows 

 on a basis of 100 parts of dry substance: 



It is interesting to note that fatty acids evidently as intermediate 

 products have been observed during the formation of the fats. 3 How 

 the transformation, as a whole, is effected, has never been explained. 



We also know that the reverse process, i.e., the formation of sugars from 

 the fats, also takes place, and this has been followed in the case of germi- 



1 A. Roussille: ibid. 86, 610 (1878). 



3 Ibid. 123, 1084 (1896). 



3 von Rechenberg: Ber. 14, 2216 (1881). 



