n's experiment in lymphatic leukaemia, for
example, where the artificial suppuration consisted only of polynuclear
neutrophil cells, that the polynuclear cells were formed in the tissue,
since in the blood they were present in very small percentage. For in
this case too the same incongruity between the blood and the particular
tissue exists.

2. Adolph Schmidt has urged the converse argument. He shewed that in the
sputum of patients with myelogenic leukaemia no more eosinophil cells
were present than are commonly to be found in the bronchial secretion,
although the blood was unusually rich in eosinophil cells. In our
opinion however this observation does not support the hypothesis of
local origin, but on the contrary is clear evidence that not the larger
or smaller number of eosinophil cells in the blood decides their
emigration, but the presence of specifically active chemical stimuli.
For we know from our observations on leucocytosis in infectious diseases
that the bacterial stimulating substances act on the eosinophil cells
rather in a negative than in a positive sense. And if ordinary sputum is
not rich in eosinophils in spite of a marked eosinophilia of the blood,
this only corresponds to our experience in general. Indeed, this
phenomenon is quite similar to Neusser's pemphigus experiment, where
the specific foci of disease shewed an eosinophilia, whilst abscesses
produced artificially, on the contrary, only neutrophil cells. Finally
we may employ, to support our view, another analogous experiment of
Schmidt himself. He found numerous eosinophil cells in the sputum of an
asthmatic patient, but only neutrophil cells in an artificially produced
suppuration of the skin.

Thus we see that the chief reasons brought forward by the supporters of
the theory of local origin are not proof against the most obvious
objections that can be raised from the chemiotactic standpoint.
Moreover, neither histological nor experimental proof has been given for
this theory in spite of numerous investigations in this direction. All
the same, it should not be out of place to explain the possibilities
that are given for a local origin of the eosinophil cells. First, the
eosinophil cells might be the result of a progressive metamorphosis of
the normal tissue cells. That such a process is possible, is proved by
the local origin of the mast cells. These may arise, as Ehrlich and his
school have always assumed, by transformation of pre-existing