932 



SCIENCE. 



[N. S. Vol. XVI. No. 415. 



oxygen, or that it should have been much 

 less than in the other case, whereas the 

 reverse is what is found. Hence Schiitzen- 

 berger advocated the view that the sugar 

 is alimentary and not respiratory. 



Certain facts more recently discovered 

 support strongly the view that the nutri- 

 tion of the yeast is the chief object of the 

 process normally, though we cannot deny 

 that when partial asphyxiation sets in fer- 

 mentation is resorted to by the plant in its 

 diifieulty, that it may obtain the energy 

 normally supplied by the respiratory pro- 

 cesses. The mode of decomposition of the 

 sugar, however, the formation of alcohol 

 and carbon dioxide, raises a question as to 

 the exact form in which the nutritive ma- 

 tei-ial is siipplied to the protoplasm. 



Of these more recent discoveries the work 

 of Devaux on the trunks of trees may be 

 mentioned first, as it seems to point to a 

 similar problem to the one connected with 

 j'east. Devaux examined the composition 

 of the air in the interior of woody stems 

 growing under normal conditions, and 

 found that the proportion of oxygen it con- 

 tains often sinks as low as ten per cent., 

 while in a few cases, in the most internal 

 part of the tree, he found this gas to be 

 entirely absent. The disappearance of 

 oxygen becomes easier with every increase 

 of temperature. This partial asphyxiation 

 is attended by the formation of alcohol in 

 the struggling tissue, the spirit being de- 

 tected by cutting up the branches of the 

 trees and distilling them with a large ex- 

 cess of water. Devaux 's experiments were 

 made upon a considerable variety of trees, 

 among which may be noted Castanea vul- 

 garis, Pyrus domestica, Alnus glutinosa, 

 Ulmus campestris, Samhucus nigra and 

 Ficus Carica. 



Similar results have been obtained by 

 ilaze in some researches on seeds. When 

 a number of these are submerged in water, 

 microorganisms being properly guarded 



against, they do not readily germinate, but 

 their weight nevertheless somewhat rapidly 

 diminishes. In some of Maze's experi- 

 ments with peas he ascertained that this 

 diminution was attended by a considerable 

 formation of alcohol. Three parcels of 

 forty peas were examined, weighing re- 

 spectively 10, 17 and 27 grams, and the 

 experiments lasted 6, 12 and 27 days. He 

 found the proportion of alcohol to the 

 original weight of the peas was 2.34, 4.63 

 and 6.56 per cent. As the peas were sub- 

 merged, and so kept out of contact with air, 

 it seems possible to suppose we have here 

 again an effect of asphyxiation. Other 

 experiments, however, make this view un- 

 satisfactory. He germinated twenty peas 

 at 22° C. for seven days under normal con- 

 ditions, till their axes were about 1| inches 

 long. He then covered them with water, 

 in some cases leaving the terminal bud 

 exposed to air. The development of the 

 submerged plants stopped at once, and at 

 the end of five days the liquid contained 

 130 milligrams of alcohol. The seed- 

 lings whose terminal buds were exposed to 

 the air continued to grow without showing 

 any disturbance. Maze concludes that the 

 alcohol produced was utilized by them in 

 their growth, and suggests that it is a nor- 

 mal and necessary product of the digestion 

 of carbohydrate material in seeds in course 

 of development. 



He goes on to show that alcohol can be 

 demonstrated to be present in plantlets that 

 have germinated for forty-eight hours at 

 23° C. under normal conditions. 



Another worker of great eminence who 

 has found similar conditions to exist in 

 normal vegetation is Berthelot. He put 

 blades of wheat and leaves of the hazel in 

 flasks, displaced the air by hydrogen, and 

 distilled. In the case of the wheat he 

 heated the flask to 94° C, in that of hazel 

 he conducted the distillation by passing 

 steam through the flask. In both he found 



