4 



THE BEGINNINGS OF II FE, 



1 



assu 



med to exist by nearly all those who have taken ' r te of ^th^'' 

 in the controversies concerning the possibility of ^ns imp^^^^ 



} 

 I 



part in the controversies concerning the possibility of 



' spontaneous generation/ This error may again be .hort desic^ 



ascribed to the misguiding influence of a treacherous 



analogy. Whilst it may be true that certain seeds 



and spores^ and also that Rotifers^ ' Sloths/ and some 



desiccation 



for 



Nematoids are capable of resisting the influence of a 



prolonged exposure to desiccating influences^ it may 

 well be asked^ whether the same fact necessarily holds 

 good for organisms such as Bacteria^ having no chi- 

 tinous or other envelopes to protect them, and which 

 are merely minute fragments of naked protoplasm. 

 Having elsewhere ^ shown how far presumptions had 

 stolen a march upon established facts, in reference to 

 the supposed possession of a similar property by the 

 Free Nematoids, my eyes were opened to the reahty 

 of this uncertainty with regard to Bacteria. It is, 

 however, no easy matter definitely to prove or to 

 disprove the possession of this property by organisms 

 SO minute as Bacteria^ and therefore so difficult to 



65° F 



s 



\ 



identify. If dried Bacteria are added to a drop of a 

 suitable solution — similar to that in which they bad 

 been bred — it soon becomes quite impossible to dis- 

 tinguish those which have been added from those which ^ 

 arise in the fluids. 



Taking into consideration the * 



/hich 



^ 'Philosophical Transactions/ i866, pp. 616-619. 



2 And similarly if we introduce dried Bacteria into a solution "^ 

 will nourish them^ although it had previously no tendency to breed ine ^ 

 de novo, and Bacteria are subsequently produced, we cannot safely ai"^ 



are ren 



organisms wit 

 Amceb^, Mon 

 Vorticelte, an 



And as a 

 Dr. Burdon Sa 

 elusion, not o: 



zymes 



the applicatic 



Bacteria are d 



ment by thori 

 cation induce 

 them for two 

 exposed to a 

 a far lower te 



and their gei 

 in many hot c 

 occurs with a 

 Certain ot 

 ^uthoritativel 



^ *«' are ,h, 



1!"; *«««= ■;: 



acted as 



mere i 



novo nv, , '^'^ c 



