JDTIOLOGY OF TUBERCULOSIS. 
75 
analogous process in 'which also staff-shaped bacteria are incorporated by the col¬ 
orless cells of the blood. This case is the putrefaction of the blood in mice 
(Miiuse-septiciimie) described by me in the “Investigations of the iEtiology of 
Infectious Diseases.” In this disease bacilli very similar to the tuberculous bacilli 
are to be found in the interior of the white blood corpuscles, and at first there are 
only one or two specimens close to the nucleus ; then they increase very rapidly 
in the cell, destroying the nucleus and finally bursting the cell in order, having 
become free, to be again taken up by other cells and to prepare for them a rapid 
ruin, so that in a short time the majority of the white blood corpuscles are found 
inhabited by bacilli. The tuberculous bacilli grow, as we shall see later, very much 
more slowly than the bacilli of septicamie (putre. of blood;, and the cells laden 
with them can therefore manifest vital functions very much longer. The further 
course of both diseases is, in accordance with this fact; very different, in spite of 
the fact that the first beginnings of the bacteria invasion possess such great simi¬ 
larity. 
Direct observation also speaks in favor of the assumption that tuberculous 
bacilli are first seized and transported by the wandering cells. This can best be 
recognized in the cases in which considerable numbers of bacilli are introduced 
directly into the course of the blood, for example, by injection into the ear veins 
of the rabbit. If an animal infected in this manner be soon killed, one still finds 
in the blood numerous white blood corpuscles which enclose one or more tuber¬ 
culous bacilli, and moreover in the tissue itself of the lung, liver and spleen, 
genuine round cells appear which are provided with a simple or divided nucleus, 
still possess no epithelioid form, therefore exactly resemble the colorless blood 
cells and yet contain tuberculous bacilli. Another explanation of this, other than 
that they are wandering cells which took up the bacilli in the course of the blood 
and transported them into the neighboring tissue, will scarcely be found Also 
in the case of guinea pigs into whose bauclihohle (belly cavity) considerable num¬ 
bers of tuberculous bacilli were injected, and which died in the course of the first 
week, the same appearances were found. 
A third ground for this assumption appears to me to lie in the fact that in 
dead tissues, in such places, therefore, wherein the influence of the living cells upon 
the bacilli is completely excluded, when a lively growth of the bacilli takes place, 
they arrange themselves in typically formed groups which resemble the peculiar 
forms of the bacteria colonies in reinculturen of the same on blood serum. 
We must therefore consider these forms to be those taken by tuberculous 
bacilli when developing undisturbed and when their grouping is decided only 
by the variations and changes of place conditioned by their growth. Every 
other arrangement is to be looked upon as the working of some sort of disturbance, 
for example, that caused by currents in the liquids, or by the direct influence 
of movable tissue elements. So the relative positions of the bacilli in the giant 
cells, especially their position as opposed to the nucleus, and the radiating ar¬ 
rangement appear to me to be conditioned upon currents in the plasma of the 
cell, and not by motion belonging to the bacilli themselves, since the bacilli 
after the death of the cells do not change the radiating arrangement once taken. 
After the wandering cell which transported the bacillus has changed itself 
into an epithelioid cell and given up moving from place to place, the path- 
