ORIGIN OF INFUSORIA. 
337 
same wa} r , they placed a piece of gun-cotton, selected from 
the middle of a considerable mass of that material which had 
been kept in a closed bottle, and was as free as possible from 
atmospheric dust-particles. In C they placed the same de¬ 
coction, with calcined air, and no cotton, while D was sub¬ 
jected, like the preceding, to a second ebullition, but was 
allowed to remain open. A fifth, E, was closed during the 
second boiling. After five days A was opened, and found to 
contain long Bacteriums, and a clot of a branching and en¬ 
tangled mycelium. This was the result obtained by M. Pas¬ 
teur. B was opened two days later, and contained what the 
writers call dead Bacteriums reduced to granulations, and on 
a portion of the gun-cotton which extended beyond the tube 
there was a fine mycelium, identical with that in A. C was 
opened on the same day with A, and exhibited Bacteriums, 
but rather fewer than A, and no mycelium. “This result/' 
say MM. Joly and Musset, “confirms once more those which 
we obtained last year, in repeating the experiment of Schwann, 
and it proves, contradicting the assertions of M. Pasteur, that 
air heated and then cooled does not leave intact the juice of 
meat which has been exposed to ebullition. On the sixth 
day D, which had remained open, exhibited no infusoria, 
but two days later swarmed with long and active Bacteriums. 
Eight days later E exhibited no infusorial life. Another set 
of experiments showed that distilled water containing a tuft 
of gun-cotton charged with atmospheric dust produced few 
organisms, and sometimes none; that similar water, to which 
a considerable quantity of dust was added, yielded Bacteriums 
and monads; that if aster leaves, carefully washed in pure 
water, were placed in distilled water, ciliated infusoria appeared. 
Distilled water used to wash a large quantity of mercury 
from a pneumatic trough “remained unfertile, although one 
of the enemies of heterogeny affirmed that a single globule of 
mercury was enough to people any infusion." 
Following M. Pouchet, MM. Joly and Musset placed a 
considerable quantity of a filtered infusion of chopped hay in 
one vessel, and then floated in it a smaller vessel containing 
some of the same infusion. In the large vessel they obtained 
ciliated infusoria, and only Bacteriums and monads in the 
little one. It is not stated how long they kept these vessels 
to see what they would yield. 
It is possible that after a greater lapse of time ciliated in¬ 
fusoria might have appeared in the smaller vessel, as they 
can certainly be obtained with very small quantities of fer¬ 
menting hay;* but if not, it does not follow, as these gentle- 
* Mr. Slack tells us that he has obtained kolpods and other ciliated in- 
