ON THE NATURE OF MITOCHONDRIA 209 
three hours after the preparation was made, the bacilli did not 
appear to have absorbed any more of the dye. 
3. Bacillus subtilis. A few moments after the preparations 
were made, deeply stained granules could be observed in the 
bacilli, while the cytoplasm of the bacilli was very faintly stained. 
In some bacilli the granules were very small, in others they were 
quite large. Figures 1 to 3 are camera-lucida drawings of some 
bacilli from these preparations after different lengths of time in 
staining. 
4. Bacillus megatherium. The preparations contained a great 
number of spores besides the bacilli. The spores appeared to 
be tinted by the dye. The staining reaction of the bacilli varied 
in different preparations, apparently depending upon the age of 
the culture. In some eases the cytoplasm was distinctly stained, 
while in other cases it was not stained, but contained intensely 
stained granules. Figures 4 to 6 represent camera-lucida draw- 
ings of bacilli from various cultures with different lengths of 
staining time. In one preparation the cytoplasm was quite 
intensely stained immediately after application of the dye. When 
it was examined three hours later, the majority of the bacilli 
had swelled to about three times the normal size and contained 
very large intensely stained granules. A drawing was not made 
of this preparation and I have been unable to get the same re- 
sults again. 
5. Unknown bacilli and cocci from a mixed culture. Both 
the bacilli and cocci were intensely stained immediately after 
preparation was made. There were a number of bacilli that 
were unstained. Obviously, it could not be determined in the 
preparation if they belonged to the same strain that did absorb 
the dye. Observed ten hours after the preparations were made, 
a number of the bacilli were swollen and contained large intensely 
stained granules, other bacilli were unstained. 
6. Unknown bacilli and spores, apparently a pure culture, 
made from the intestinal contents of a rabbit. The bacilli were 
intensely stained immediately after the dye was applied. The 
spores appeared to be tinted by the dye. 
THE AMERICAN JOURNAL OF ANATOMY, VOL. 30, NO. 2 
