30 MEETING OF INSPECTORS OF APIARIES. 
which seem to me only explicable on the supposition that they also grow by 
sending out buds from one end. <A bacillus may be seen with a small, some- 
what conical stained peint attached to one end, though separated by a marked 
division. This is certainly not the common mode of growth by fission, for there 
the rod seems to divide into two pretty equal halves, while here we have but a 
minute piece attached to one end. 
The mode of formation of spores may be traced in a similar manner to that 
described above in the case of the sprouting of the spores. It is, however, as a 
rule, necessary to leave the organisms to grow for a much longer time than in 
the former instance. I have not found development of spores as a rule before 
twenty-three hours, but this depends very much, apparently, on the amount of 
fluid that was present and the number of bacilli introduced at the time of 
inoculation. The first thing noticeable is that the red begins to swell and 
becomes spindle shaped. The swelling, which generally affects the middle of 
the rod, may in some cases be most marked toward one end, increases in size, 
and the center of the swelling gradually ceases to take on the stain. The eap- 
sule of the spore is apparently also formed within the rod, and is not merely 
the cuter part of the rod. In three or four hours the rod is seen to have almost or 
completely disappeared, leaving the spore lying free or within the faint outline of 
the original bacillus. It seems to me that the view that spore formation occurs 
when the food is getting exhausted is correct, for the time at which this appear- 
ance is found depends greatly on the drop placed on the cover glasses, and I 
have found in one experiment that in one specimen, after twenty-three hours, 
most of the rods were forming spores, while in another specimen where the drop 
was much larger there was no trace of spore formation after twenty-eight 
hours. I have here described the results of my earlier and rougher attempts 
to study the formation of spores. I have, however, now improved the method 
in the following way. As I have just now shown, the period at which spores 
are first seen seems to depend mainly on the amount of fluid used and the 
number of bacilli introduced, and as in the above method, both these factors 
vary in each case, one can not get a regular series of preparations showing the 
different stages at different times. In studying the sprouting of spores the 
amount of fluid and the number of spores does not matter, for if sufficient nutri- 
ment is present and a proper temperature is maintained the spores must sprout, 
and probably they always take about the same length of time. The difficulty of 
obtaining a series of specimens illustrating spore formation is easily obviated 
in the following manner. Take a pure flask containing a small quantity of 
sterilized infusion and inoculate it from a cultivation containing only bacilli. 
Place it in the incubator for two or three hours so that the bacilli may increase 
somewhat in number and diffuse themselves through the liquid. Thus the culti- 
vating material contains bacilli pretty equally diffused through it, and if after 
shaking the flask drops of equal size are taken, each will probably contain 
about the same number of bacilli. The minutest quantity of fluid can easily be 
obtained by means of a syringe having a fine screw on its piston and a large 
nut revolving on this screw. The circumference of the nut being equally divided 
into a number of small segments, the same quantity of fluid can always be 
expelled from the syringe. By proceeding in this way equal-sized drops con- 
taining an equal number of bacilli can be used and a regular series of specimens 
obtained. I have found that using two-fifths of a minim containing one bacillus 
and keeping the specimen at 36° C., the earliest appearance of spore formation 
was evident in forty-one hours. 
Leaving these matters, which are of great interest not only in regard to the 
Bacillus alvei, but to all spore-bearing bacteria, and which I have therefore 
