FOREWORD 21 



gested, that anterior to the appearance of living 

 things on the Earth there would probably first 

 have been a very slow elaboration of some pro- 

 teid compounds before the actual production of 

 protoplasm in some amorphous condition like the 

 hypothetical Bathybius of Huxley, followed in 

 the course of time by the evolution of actual 

 Amoebae. 



How, then, could those holding such views look, 

 in the first place, except with extreme incredulity, 

 at experimental results which show that not only 

 Bacteria of well-known types, but that Torulas of 

 most varied kinds with the potentiality of straight- 

 way growing into simple forms of well-known 

 Moulds, are some of the common, everyday ex- 

 emplars of new-born living matter? 1 The diffi- 

 culty would doubtless be great, and the evidence 

 would require to be irresistible before such persons 

 could renounce all their preconceptions and accept 

 facts which at first sight seem incredible. 



But the evidence is irresistible, as may be real- 

 ised when it becomes obvious that, on the one 

 hand we have to do only with hypotheses and pre- 

 conceptions entirely devoid of any direct evidence, 

 and on the other the results of simple experiments, 



1 Ae to this point, see what is said in Chapter X., p. 100. 



