290 



Profs. Percy Frankland and Marshall Ward. 



respects, however (e.g., as regards habitat and mode of liquefaction, 

 &c), there are suggestive resemblances, and Mace regards it as 

 identical with B. fluoresceins liquefaciens. 



Bacillus termo is the name given by Mace to a form which he sepa- 

 rated from the mixture which previously passed under the name of 

 Bacterium termo (Dujardin), and it presents several impressive simi- 

 larities to our form. 



It is very common in water, and has the size and shape and modes 

 of union and movement observed. In fact almost the only serious 

 discrepancy we find as regards the habit of the two forms is that ours 

 has not the peculiar wavy or "amoeboid " contour of Mace's form. 



As will readily be understood, the critical examination of these 

 water bacteria is a matter of time, and requires much care ; neverthe- 

 less, I regard it as of great importance to the object we have in view, 

 and propose now to give an example of one of the lines of inquiry 

 which ought to be pursued as closely as possible, and which can only 

 be properly pursued when the separate water organisms have been 

 thoroughly studied. 



Experiments on the Behaviour of Anthrax sown simultaneously with 

 B. fluorescens liquefaciens in Water. 



For many reasons, and especially because tVs is a common water 

 form, perhaps the commonest Schizomycete in the Thames, it seemed 

 worth while to try the effect of sowing Bacillus anthracis and this 

 B. fluorescens liquefaciens together in the same water. The following 

 experiments were accordingly carried out : — 



A litre flask was filled about three-quarters full (700 c.c.) of 

 sterilised distilled water and plugged with cotton wool, and the whole 

 carefully sterilised and allowed to cool, and a very dense sowing of 

 a mixture of active anthrax and of B. fluorescens put into the water. 

 The sowing was accomplished as follows : — 10 platinum loops full of 

 a vigorous two-day agar culture of anthrax were rubbed into a sterile 

 test-tube with 1 c.c. of sterilised distilled water ; then 10 loops of a 

 B. fluorescens culture as equal as possible were treated in the same 

 way in another tube, and the contents of the two tubes mixed and 

 shaken thoroughly. 1 c.c. of this mixture was finally put into the 

 700 c.c. of the sterilised distilled water and thoroughly mixed by 

 shaking. The flask was then placed in the dark incubator at 20° C. 

 Every effort was made to introduce as little of the culture media 

 (agar) as possible, and to sow approximately equal quantities of each 

 Schizomycete, though of course it was impossible to attain these 

 objects completely. Then plate cultures were made day after day — 

 starting with one made directly on sowing the bacteria — to see what, 

 if any, effect the straggle for existence would present. 



The results are shown in the annexed table : — 



