n our observations, which are very
numerous upon this point, embracing several hundred cases, and carried
out with particular care, no nucleated red blood corpuscles in this
space of time can be found in man[8].

4. The polychromatophil degeneration can frequently be observed in
nucleated red blood corpuscles, particularly in the megaloblasts. This
fact can be so easily established that it can hardly escape even an
unpractised observer, and it was sufficiently familiar to Ehrlich, who
first directed attention to these conditions. The fact that the
normoblasts, which are typical of normal regeneration, are as a rule
free from polychromatophil degeneration, gave the key for the
interpretation of this appearance. And similarly for the nucleated red
blood corpuscles of lower animals. Askanazy asserts that the nucleated
red blood corpuscles of the bone-marrow, which he was able to
investigate in a case of empyema, shew, immediately after the resection
of the ribs, complete polychromatophilia. This perhaps depends on the
peculiarities of the case, or on the uncertainty of the staining method:
eosine-methylene blue stain, which is for this purpose very unreliable,
since slight overstaining towards blue readily occurs. (We expressly
advise the use of the triacid solution or of the haematoxylin-eosine
mixture for the study of the anaemic degenerations.)

After what has been adduced, we hold in agreement with the recent work
of Pappenheim, and Maragliano, that the appearance of polychromatophilia
is a sign of degeneration. To explain the presence of erythroblasts
which have undergone these changes we must suppose that in severe
injuries to the life of the blood these elements are not produced in the
usual fashion, but from the very beginning are morbidly altered.
Analogies from general pathology suggest themselves in sufficient
number.

B. A second change that we find in the red blood corpuscles of the
anaemias, is =poikilocytosis=.

By this name a change of the blood is denoted, where along with normal
red blood corpuscles, larger, smaller and minute red elements are found
in greater or less number. The excessively large cells are found in
pernicious anaemia, as Laache first observed, and as has since been
generally confirmed. On the contrary in all other severe or moderate
anaemic conditions, the red corpuscles shew a diminution in volume, and
in their amount of haemoglobin. This contradiction, which Laache first
mention