192 Mr. J. C. G. Ledingham. [Nov. 18, 
Experiment IX.—Comparison of the Effects of Combination at 37° C. and 
at 18° C. 
Time of combination in each case, 1 hr. 40 mins. I. T. = 15 mins. 
Combination at 37° C. Combination at 18° C. 
Temperature. Cocci. Temperature. Cocci. 
37° C. 8 °6 37°C. 4-9 
18 8°5 18 6-1 
It will be seen that after combination at 18° C. the amount of phagocy- 
tosis at 37° C. is even slightly exceeded by that at 18° C., though both 
fall very short of the corresponding figures obtained after combination at 
one C, 
Experiment X. 
Technique similar to that of Experiment IX. Temperatures of combination, 
37° and 7° C. Time of combination, 3 hrs. 15 mins. Time of incubation, 
20 mins. 
Combination at 37° C. Combination at 7° C. 
Temperature. Cocci. Temperature. Cocci. 
3%, G3 : 23 °0 Sis 6°6 
21 28°6 21 5°8 
18 27 8 18 6°8 
10 12:0 10 4:0 
In each series, between the temperature range 37° C. to 18° C., the 
phagocytic values are practically identical, but the great differences between 
the absolute amounts in the two series afford a striking illustration of the 
superiority of combination at 37° C. 
Experiment XI.—This experiment was designed to show the effect of 
varying the combination times at the two temperatures 37° C. and 18°C. 
Samples for phagocytic purposes were removed from the serum-coccal 
mixtures every half hour and exposed to the action of the leucocytes. 
Combination at 37° C. Combination at 18° C. 
Temperature. Combination time. Cocci. Temperature. Combination time. Cocci. 
BY faa OF 30 mins. 50 37° C. 30 mins. 4, °7 
18 30 mins. 4:1 18 30 mins. 5°4 
37 1 hr. 8 °4 ay 1 hr, BS if 
18 1 hr. 9°2 18 1 hr. 7:3 
37 1 hr. 30 mins. 8°9 SH 1 hr. 30 mins. 7-4 
18 1 hr. 30 mins. 8 °*4 18 1 hr. 30 mins. 7°0 
37 2 hrs. 10°7 Si 2 hrs. 8°3 
18 2 hrs. 10 °5 18 2 hrs. i2 
The pairs of phagocytic values in the various time intervals approximate 
very closely in the two series, showing that, under the conditions indicated 
