44 Killing of Botrytis Sjwres hy Phenol 



Table XX. 20. 4. 20. 6 day spores. Phenol 0-4 and 0-7 per cent, 

 with same suspension, 60,000 spores in 1 c.c. 25-6° C. 



will be seen that the experimental curve is not far removed from the 

 normal. But if the 0-5, 0-6 and 0-7 per cent, curves are similarly trans- 

 posed, the resulting frequency curves do not resemble normal curves. 

 They are skew, the modal value has moved to the left, and moves further 

 and further to the left, the greater the strength of phenol used {v. Fig. 9). 

 If a logarithmic survivor curve were similarly transposed, it would give 

 a "frequency curve," which has somewhat the shape of a reversed J, 

 with the modal value on the extreme left. 



This extreme J-form is a very unhkely form of distribution to find 

 in an assemblage of Botrytis spores. Biological frequencies of this type 

 are, of course, known, but they are very uncommon and we should not 

 expect to find them here. This distribution is so unusual that those 

 observers who regard the logarithmic as the typical disinfection curve 

 reject (Chick, Eijkman, Arrhenius, etc.) the possibihty of explaining it 

 on any frequency basis whatever. They consider that though individual 

 variations may be in part an explanation of departures from the log- 

 arithmic type, phenomena of quite a different category are responsible 

 for the logarithmic type itself. Thus Chick in her first paper (3) looks 

 on the bacteria as comparable to molecules with an internal cychc 

 revolution, and the interaction between poison and organisms as analo- 

 gous to the inversion of sugar in presence of acid. She later transfers 

 the interaction from the whole bacterium as such to the protein molecules 

 it contains, and expressly rejects the possibihty of resistance variations 

 amongst the individuals having any significance when the reaction runs 

 logarithmically. Arrhenius (13) says "there is no doubt that the individual 

 cells in a sample of bacteria or red corpuscles possess a different power 



