36 Living and Dead Matter and 



grain found in the Egyptian tombs was still able to 

 germinate has long been recognized as a myth. Miss 

 White' found that in wheat grains, there appeared a 

 well-marked drop in their germinating power after 

 about the fourth year, reaching zero in eleven to seven- 

 teen years. In a drier climate they last longer than 

 in a moist climate. It is of importance that the hydro- 

 lyzing enzymes in the seeds, such as diastase, erepsin, 

 remained unimpaired even after the germinating power 

 of the seeds had disappeared. The seeds were able to 

 resist for two days the temperature of liquid air, though 

 the subsequent germination was delayed by this treat- 

 ment. Macfadyen^ exposed non-sporing bacteria, viz., 

 B. typhosus, B. coli communis, Staphylococcus pyogenes 

 aureus, and a Saccharomyces to liquid air. 



The experiments showed that a prolonged exposure of 

 six months to a temperature of about — 190° has no ap- 

 preciable effect on the vitality of micro-organisms. To judge 

 by the results there appeared no reason to doubt that the 

 experiment might have been successfully prolonged for a 

 still longer period. 



Paul Becquerel^ found that seeds which possess a very 

 thick integument may live longer than the grain in 

 Miss White's experiments. The thickness of the in- 

 tegument prevents the exchange of gases between air 



' White, J., Proc. Roy. Soc, 1909, B, Ixxxi., 417. 

 ' Macfadyen, A., Proc. Roy. Soc, 1903, Ixxi., 76. 

 3 Becquerel, P., Revue generate des Sciences^ 1914, xxv., 559. 



