988 REPORT—1896. 
(guinea-pigs) show that the onset is never less than 5 minutes after injection. 
The time of onset varies somewhat according to the nature and temperature of the 
injected fluid. 
Metschnikoff, and Kanthack, and Hardy attribute the leucopenia to a sudden 
destruction of the cells. Metschnikoff considers that this solution of cells (‘ pha- 
golyse’) imbues the peritoneal fluid with increased bactericidal power. 
The author does not agree with these statements; first, because the cells may 
be found again during the leucopenic stage, and secondly because. when inert 
resistance substances (e.g., carbon particles) are introduced, they disappear in 
considerable proportion at the same time as the cells. His observations are con- 
sequently in accordance with those of Mesnil on the leucopenia which occurs after 
intra-vascular injections ; this observer has shown that the cells are stopped by 
adhesion to capillary walls—more particularly in the liver. At the beginning of 
the year (Wiener klin. Wochenschr Nos. 11 and 12, 1896), it was shown by Prof. 
Gruber, and the author, that large numbers of the cells become deposited upon the 
omentum, though some become adherent to other parts of the peritoneal lining 
after intra-peritoneal injections. 
The mechanism of this deposit appears to be as follows: the hyaline and 
megoxyphil cells adhere together into masses or ‘ balls’; these ‘balls’ are driven 
by the peristaltic, and other abdominal movements, to the omentum and upper 
region of the cavity, where they become adherent. In animals killed at recent 
periods after intra~peritoneal injection, the peristaltic movements are exceptionally 
active. 
At the same time numbers of bacteria, in the case of infections, also become 
deposited on the omentum, etc. ; especially if some serum having a ‘clumping’ 
action has been mixed with the bacterial emulsion. By the use of indian ink the 
phenomenon may be demonstrated to the naked eye by removing samples with 
capillary tubes. By the action of the abdominal movements the omentum becomes 
rolled up; it is also intensely injected in acute infections. Soluble substances 
such as carmine, or potassium ferrocyanide solutions, have a predilection fur the 
omentum apparently independently of the leucocytes. It is suggested that possibly 
bacterial toxins may be dealt with to some extent in this manner. 
The leucopenic stage lasts about an hour, when a cell normally foreign to the 
peritoneal cavity (the finely granular oxyphil (K. and H.) or ‘microxyphil’ cell, 
or polynuclear leucocyte) makes its appearance. The period of leucopenia has been 
called a ‘ period of negative chemiotaxis’ by Issaeff; however, especially with 
microbes of a comparatively low degree of virulence, very active phagocytosis is 
established by the hyaline cells; these cells ingest the microbes without any pre- 
liminary intervention on the part of the megoxyphil cells; the microbes attached 
to the hyaline cells may be almost countless, whilst many of the megoxyphil 
cells are free from or at any rate only have a few attached microbes. One indu- 
bitable instance of phagocytosis by megoxycytes has been observed. 
Metschnikoff states that ‘ phagolyse’ does not occur after injections during the 
leucocytotic condition induced by an injection (e.g., pepton-broth) given twenty-four 
hours previously, The author does not agree with this statement, for he finds that 
the cells then present (microxyphil cells and macrophages) ‘dail’ together, and 
disappear by adhesion to the peritoneal linings, in a manner similar to that which 
occurs in normal (previously untreated) animals. This has been demonstrated to 
the naked eye by giving coloured injections (e.7., indian ink, or carmine granules) 
during the leucocytotic period, and seeing the disappearance of the coloured 
material from capillary samples; also by marking the cells by previous injections 
(e.g., peptonate of iron, carmine, etc.), and watching their disappearance. The 
disappearance can also be traced by care after bacterial inoculations; but owing to 
the abundance of cells, only a proportion of which disappear, the observation is 
less readily made than when coloured materials are used. The ‘ncreased re- 
sistance’ first identified by Issaeff, obtained by producing a leucocytosis by means 
of simple injections, is suggestive of being of great practical value in the treat- 
ment of peritoneal cases in man, where there is some risk of infection (perityphilitic, 
pelvic abscesses, &c.), if operation is undertaken: these points will be more fully 
