62 AERATION AND AIR-CONTENT. 



such tissues showed oxygen to be present in only one-thirty-fifth of 

 the volume. 



Recent researches. — Gerber (1903 : 269) found that increased oxy- 

 gen increased the respiratory quotient and hastened the ripening of 

 unripe bananas, but decreased the respiratory quotient of ripe 

 bananas. 



Smirnoff (1903 : 32) showed that wounding produced no increase 

 in intramolecular respiration. The latter at first decreased in hydro- 

 gen, but nearly or quite regained its original intensity in about 40 

 hours, beginning to fall off again on the fifth day. If, however, the 

 wounded bulbs were placed in air instead of hydrogen between 

 experiments, there was an increase in the energy of intramolecular 

 respiration nearly proportional to that of the normal respiration. 



Stoklasa, Jelinek, and Vitek (1903 : 493) reached the conclusion 

 that the anaerobic respiration of the sugar-beet is essentially identical 

 with alcoholic fermentation by yeast. In both cases, CO2 and alco- 

 hol are the chief products, while by-products appear in insignificant 

 quantity. The same quantitative relations between CO 2 and alco- 

 hol occur as in alcoholic fermentation by yeast. They regard it as 

 fully demonstrated that the anaerobic respiration of sugar-beet 

 under the complete exclusion of microbes is an alcoholic fermenta- 

 tion, and that its products, alcohol and CO2, are true excretions. 

 The presence of enzymes similar to those of invertase and zymase 

 shows that the anaerobic respiration of the sugar-beet is extraordi- 

 narily like that of the yeast-cell. 



Godlewski (1904) observed that lupine seeds in pure water with- 

 out oxygen developed only a very weak intramolecular respiration 

 for 6 to 8 weeks. This could be greatly strengthened by adding 

 the proper sugar. In the latter case the intramolecular respiration 

 depended upon alcoholic fermentation. In solutions of both fruit- 

 sugar and cane-sugar the seeds may germinate partially without 

 access of oxygen and the radicles reach a length of 3 to 6 mm., when 

 they slowly die. He concluded that the decomposition of albumen 

 can occur in the absence of oxygen, but that the synthetic formation 

 of asparagin as the beginning of albumen regeneration was impos- 

 sible with the higher plants. 



Gola (1905) studied the seeds of Trapa natans and the rhizomes 

 of Nuphar luteum and Nymphcea alba during the period of rest as 

 well as of germination and found alcohol present in the storage 

 tissues. He thought this to be due to the unfavorable conditions 

 for aeration in swamps, which result in anaerobic respiration. 



Palladin and Kostytschew (1906) made further studies of anaero- 

 bic respiration in relation to alcoholic fermentation, with the follow- 

 ing results : A considerable amount of alcohol is formed in the anaero- 

 bic respiration of living seeds and seedlings of Lupinus, and the 



