S. C. EROOKS 79 



Should we not then conclude that the course of processes like dis- 

 infection is, like h in Fig. 4, the result of the simultaneous operation 

 of two factors: the frequency curve of variation in individual resist- 

 ance, which may be different for each group of cells and each toxic 

 agent; and the course of the fundamental reaction, which usually 

 proceeds with a velocity diminishing during the experiment at a rate 

 dependent on the particular conditions prevailing? We must also 

 bear in mind that what we have supposed to be the fundamental reac- 

 tion may be the end result of a complex series of interrelated or " cate- 

 nary" reactions. If some one hnk in this chain of events is a change 

 which, from the beginning to the end of the process, is so slow as to 

 govern the rate of the whole series, which taken together is regarded as 

 the fundamental reaction, then, and only then, will orderly laws 

 describe the course of the latter. 



This conception does indeed render a solution of the problem much 

 more difficult than it once seemed, but not necessarily unattainable. 

 A proper understanding of this "group experiment," as we might 

 perhaps call the widely employed type of which disinfection is but one 

 example, should lead to better interpretation of the phenomena them- 

 selves, and a far deeper insight into the fundamental life processes to 

 which they are due. 



CONCLUSIONS. 



1 . The course of such processes as hemolysis is very largely depend- 

 ent upon variations in resistance among the different individuals, 

 and secondarily upon the course of the fundamental reaction. 



2. The fundamental reaction may be either a simple process, or 

 the expression of a complex series of changes whose rate is at all times 

 governed by that of the slowest of the series. This might perhaps be 

 regarded as another expression of the so called "Law of the minimum." 



3. Unnatural assumptions would be requisite for the explanation of 

 a resemblance between the course of such processes in general and 

 that of a monomolecular reaction. 



4. The supposition that such a general resemblance exists is not 

 supported by the available evidence. » 



