326 PROFESSOR LISTER ON THE GERM THEORY 
peared entitled to greatest weight, I had regarded these organisms as a separate 
and altogether distinct group. But the contrary conclusion was forced upon 
me not only by the observation which I am now recording, but by various 
others, some of which will be described in the sequel. I need hardly remark 
that, if correct, it is of the very highest interest. 
In the present instance it is certain that the batteria moving in the liquid 
were identical, morphologically, with buds derived from the fungus; and this fact 
receives additional weight from the circumstance that the glass had been left 
untouched for eight months, having been previously securely guarded against the 
entrance of organisms from without; and even if bacteria, as such, had been acci- 
dentally introduced when the vessel was last exposed, it is in the highest degree 
improbable that they would have remained in an active condition for such a 
protracted period. If, therefore, we set aside the idea of spontaneous genera- 
tion, which I trust before this paper is concluded the reader will see that we are 
justified in doing, it is difficult to conceive how these bacteria could have 
arisen, except from a gradual alteration in the character of the original organism 
under the influence of progressive changes in the medium which it inhabited.* 
I next proceeded to examine the PasrEur’s solution. The liquid was still 
perfectly transparent and colourless, contrasting remarkably with the jet black 
colour which I had observed to result in a much shorter period from the action 
of yeast upon the same fluid.t There was, however, a good deal of white 
deposit, partly in the form of a loose sediment, partly as a delicate incrustation 
upon the side of the tube, and some white patches were floating free, probably 
in consequence of the disturbance of the vessel: there was also a little scum 
on the surface. Only about a sixth part of the liquid had evaporated; and, as 
before mentioned, the part of the glass which had been left dry was studded 
over with little gelatinous bodies like those in the tube of urine. The tube 
being longer in the present case, I failed to pick out any of those little bodies 
with a needle. I was therefore obliged to content myself with examining a 
drop taken with “heated” pipette from the upper part of the liquid, including 
some of the white floating particles. These, however, proved all that I could 
desire, being composed of the same organism that I had found in the urine, and 
all the better seen because it had not been disturbed by the needle. 0, ¢, andd 
of Plate XXIII. represent three entire plants, of which 0 fully equals in slender- 
ness any seen in the urine; and some idea of its exquisite delicacy may be given 
by saying that ten such threads might lie abreast in the diameter of a single red 
* It is indeed conceivable that a bacterium incapable of growing in fresh urine may have lain 
dormant in the liquid till it had become so altered under the influence of the torula as to be a suitable 
nidus for it. Meanwhile the fact of the morphological identity of this bacterium with buds from the 
filamentous fungus must be taken for what it is worth. 
+ I am not prepared to say whether the black colour which I have invariably found to be caused 
by the prolonged action of yeast upon Pastrur’s solution is due to the Torula Cerevisiew or to other 
organisms accompanying it. 

