THE RESERVE MATERIALS OF PLANTS. 487 



and sugar ; from our own standpoint perhaps the most 

 stress may be laid on Brown and Morris's (35) experiments 

 on feeding barley embryoes ; one material which led to the 

 formation of carbo-hydrate in their tissues being glycerine. 

 The fatty acid at the same time undergoes a decomposition 

 into simpler forms which are capable of dialysis. An acid 

 of this kind can be prepared from the germinating seeds 

 which will yield characteristic crystals when an ethereal 

 solution of it is slowly evaporated. The changes leading 

 to the formation of these bodies are no doubt oxidative, 

 and are carried out by the direct action of the protoplasm 

 of the cells. This is supported by the observation of 

 Godlewski already quoted, that the absorption of oxygen 

 by the "seeds is greater than the output of Co 2 during the 

 time at which these metabolic changes are most vigorous, 

 and to the experiments of Hazura and Griissner (53) and of 

 Krafft (54) who have shown separately that different fatty 

 acids do produce such crystalline products when gently 

 oxidised. 



These conclusions are in the main confirmed by the 

 researches of Du Sablon (55) upon the same seed. This 

 writer finds that the proportion of oil in the dried seed 

 amounts in some cases to 69 per cent., and that on ger- 

 mination this diminishes, the amount being only about 10 

 per cent, when the radicle is 12 cm. long. -He says that 

 in his experiments the fatty acid increases irregularly during 

 germination, and is about 0*5 per cent, of the dry weight 

 at its conclusion. He failed to identify the glycerine with 

 certainty, but found a large formation of sugar as the pro- 

 cess proceeds. 



The deposition of the fatty matter in the cells of the 

 seeds or other parts has not been so fully worked out as 

 its disappearance. There is reason to believe that it is 

 the converse of the latter ; that the various products are 

 taken to the cells in the forms of the dialysable bodies 

 described, rather than that they are completely formed 

 where the fat is deposited. 



The intervention of protoplasms is necessary for the 

 deposition of the fat or oil, but that intervention seems 



