969 
groups of cells (sometimes also separate cells) consisting for the 
greater, or, in cases, also lesser part, of myelocytes — large cells 
with round or kidney-shaped nuclei and with a pronounced granu- 
lation in their protoplasm of the same character as that of the poly- 
nuclear cells; the fact that these cells together with other, greater 
and smaller nongranulated cells of the lymphoid type, and plasma 
cells, occurred together in one group, removed all doubt about these 
cells being evolved from lympbocytes. A number of these cells were 
rather small and of the lymphoid type, others were already large 
but not granulated. Many had a basophile protoplasm with pseudo- 
eosinophile granules. These groups lay mostly perivascular. A few 
myelocytes were noticed to be in different stages of cell division. 
Besides these there occurred conglomerates of almost fully developed 
polynuclear leucocytes. Slides of the normal omentum looked quite 
different: Resting endothelial cells with some resting connective 
tissue cells between them. 
In this way there was formed, through a slight stimulus as an 
injection of NaCl 0.9°/, in the abdominal cavity, repeated a few 
times, partly through local reaction, but mostly through the deposition 
of blood elements, a young tissue process of enormous extension. 
In this region there had been deposited the lymphocytes which had 
disappeared from the blood, which lymphocytes, together with the 
hyperaemic regeneration tissue, characterised the whole as myeloid tissue. 
In this way the disappearance of the lymphocytes from the cir- 
culating blood is explained, and also the fact that. inspite of this 
disappearance, practically only polynuclear cells are met with in 
the exudation: the lymphocytes are partly at least converted into 
polynuclear cells. 
This also explains why upon a later repeated injection the animal 
responds in such a way that there is a faster occurrence of poly- 
nuclear cells in the exudation. The myeloid tissue in the abdominal 
cavity has not quite come to rest again and responds to the new 
stimulus of NaCl solution again by an instantaneous conversion of 
the lymphocytes which were present, and those which were con- 
veyed there, into granulated cells. 
We can therefore conclude that the injection of NaCl 0.9 °/, forms 
a stimulus through which by far the greater number of the white blood 
cells present in the circulating blood accumulates in the capillaires 
of the abdomen; in addition there is also seen a reaction of the 
connective tissue elements through the same stimulus and out of 
these two reactions there results a tissue which is perfectly similar 
to myeloid tissue. 
