i54 
Notes. 
sition for my friend Professor Letts of Queen’s College, Belfast, it 
occurred to me to try and revive the spores of my old culture of 
B . Megaterium which had then been torpid for nearly five years. I had 
not sufficient time to attempt isolation with a gelatine-plate, so inocu- 
lated direct from the spores on the old cover-glass, after first soaking 
them for a short time in a drop of sterilised water. I used an ordinary 
platinum needle, and with the usual precautions mounted twenty 
cover-glass cultivations, also a few blind duplicate-cultures of the 
media employed. The batch was then removed to a situation where 
a temperature of about 80-85° F. was maintained. I first examined 
these cultivations after about twenty-four hours, when they all appeared 
sterile : on a second examination the following day, however, I found 
one single development, and as the Bacilli then appeared settling 
down for spore-formation (their motion having almost ceased), I am 
inclined to think that this single growth had escaped my observation 
the previous day. Nearly all the other mounted spots remained quite 
sterile for several days after. 
The cultivation was not a pure one ; but the contrast in size between 
B. Megaterium and B. sublilis (with which I think it was contaminated) 
was very marked. 
This development of B. Megaterium from its spores seemed to me 
quite normal as regards time, and partly for this reason I think the 
observation an interesting one. 
I am inclined to think that my want of success with the remaining 
nineteen cultures of the batch, may have been due to actual rupture 
of the cells in attempting to remove them with the platinum needle. 
But it may well be that the life-limit of the spores had been reached 
in the majority of cases ; and that the successful culture was due to a 
variation in the direction of longevity. This would put the life-limit 
of the spores of Bacillus Megaterium at about four and a half years, 
which is far below that of B. subtilis or B. Antkracis . 
I again tried to revive the remaining spores of the same old cultiva- 
tion in December 1891: the cover-glass had been broken in several 
pieces, and had remained exposed for more than a year under an 
inverted tumbler in my laboratory at Bushmills. I used both solid and 
liquid media, but on this occasion failed with both — I, however, attach 
no absolute confidence to this negative result. 
ALLAN P. SWAN, Bushmills, Co. Antrim. 
