BACTERIA 



alarming extent and also that they no longer swim 

 about. At this period they tend to arrange 

 themselves in chains lengthwise, their cell walls also 

 lose their clear cut appearance and become jelly like, 

 yet withal they may still continue to split up. 



If we now examine the water from which we 

 have taken our drop we shall probably find a scum 

 floating on the surface ; it consists of millions upon 

 millions of hay bacilli, huddled together so to speak. 

 It is the beginning of the end for them, nourishment 

 is becoming scarce and important changes are about 

 to take place. Let us continue our examination 

 day by day, that we may discover what is happen- 

 ing. Before long, we shall find that within each 

 cell wall, which is no longer jelly like, there is a 

 darker cell contents than we saw before. The 

 bacilli have, in fact, formed spores. Now we may 

 plug our bottle containing the remainder of the 

 water, with cotton wool and set it aside for some 

 months if we wish. At the end of that time, by 

 pouring a fresh supply of water upon the spores, 

 we may start them all into a new vitality and the 

 whole process will be repeated. 



We have mentioned that bacteria should be 

 stained, in order to make their presence more easily 

 detected. This is hardly the place to enter into 

 a lengthy discussion concerning the methods of 

 staining but, for the benefit of our readers, who 

 wish to pursue the subject further, we will state 

 as concisely as possible how simple staining may 

 be accomplished. Our requirements are, a pair of 



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