‘ 
1525 
A description of the method is given a.o. by Hans Fini, Zeitschrift 
f. allgem. Physiol. 8, (1908) 496. 
To 4 ec. of the solutions a, 6 and c 0,1 cc. of serum is added 
and to these mixtures 0.3 cc. of the thick leucocyte-suspension. 
After they have been exposed to room-temperature for half an hour, 
during which time they were repeatedly stirred gently, 0.3 cc. of 
an amylum-suspension in NaCl 0.9°/, is added to the suspensions, 
after which they are kept at 37° in an incubator. After 20 or 
30 minutes they are simultaneously taken out and the phagocytosis 
is stopped by placing them in icewater and adding formol. Then 
preparations are made which are examined after. 
The reader will have noticed that in these experiments serum is 
added. Unlike carbon, amylum is only taken up if the fluid contains 
some serum. The most desirable quantity amounts according to 
pE Haan’s researches to 2'/, vol. percent. This was confirmed by 
OUWELEEN, who will soon publish further particulars in a dissertation. 
Further - particulars relating to the technicalities of the amylum- 
phagocytosis are omitted here. We can now proceed to summarize 
the results of one series of experiments in a table. 
TABLE £ 
Comparison of the extent of the phagocytosis in NaCl-solution, which had 
been treated with nitrogen, with oxygen and with atmospheric air. 
Phagocytes and amylum had been in contact for 20 minutes !). 
Number of leuco- Percentage of leu- 
Number of leuco- cytes having taken cocytes containing 
The leucocytes are in cytes counted 
up amylum amylum 
NaCl-solution , 
treated with nitrogen 571 159 28.5 0/0 
NaCl-solution 
treated with air 672 130 19.3%, 
NaCl-solution 835 AE 13.1% 
treated with oxygen 
1) If the leucocyte-Suspension remains at 37° in contact with amylum for a 
longer time, the values denoting the extent of phagocytosis will be greater. But 
the differences in the degree of phagocytosis become smaller and smaller. At 
length a time will come when in all three fluids the phagocytosis is the same. 
This is the case mostly after about 11/, hour. The reason is that we have to do 
with a difference in velocity. Evidently the phagocytosis went slowest in the 
solution treated with oxygen, fastest in the one treated with nitrogen. If the 
phagocytes in the oxygen solution are left sufficient time, they will finally have 
taken up amylum in as ample a degree as the phagocytes in the nitrogen-medium 
in a shorter time. 
