41 
lide 0.050 gram and heroine 0.00075 gram, 7 days. These results are 
brought together in the following summary for the sake of comparison: 
Control. 
Acetanilide mixture. 
Series. 
Acetanilide, 
Acetanilide 0.050, 
Acetanilide 0.050, 
Acetanilide 0.050, 
Acetanilide 0.050, 
0.050. 
morphine 0.002. 
morphine 0.001. 
codeine 0.010. 
heroine 0.00075. 
f 7 
5 
6 
6 
4 
10 
6 
7 
6 
5 
\ 
10 
7 
8 
7 
6 
1 11 
7 
8 
10 
7 
f 6 
3 
6 
6 
\7T 
] 9 
8 
5 
8 
Vi 
1 11 
10 
8 
8 
[ 11 
1 
J 
Average. . 
9.37 
6.57 
1 7.25 
6. 85 
6. 28 
As will be noted, the figures given in this summary do not confirm 
those of Series III, hut show exactly the opposite effect, the toxicity 
of acetanilide being increased by codeine, heroine, and morphine. The 
contributory evidence of morpliine and heroine is of special value 
when it is remembered the similarity in the effects produced by the 
drugs of the opium series and serves to substantiate the findings with 
codeine. The much larger number of mice and the uniformity in the 
results of both Series V and VI make the results of Series III prob- 
ably incorrect. The longer life of acetanilide-codeine mice in the 
earlier series is probably to be explained by some external variation 
in the condition of the mice which escaped the notice of the experi- 
menter.® 
The results of these experiments indicate, therefore, that the tox- 
icity of acetanilide is considerably increased when combined with the 
above opium alkaloids. 
TOXICITY OF ACETANILIDE AND SALICYLIC ACID. 
In a series of experiments mice were fed on cakes each containing 
0.050 gram acetanilide and 0.020 gram salicylic acid. The control 
mice fed on acetanilide alone, 0.050 gram per cake, lived 7, 7, 8, and 
10 days, or an average of 8 days. The mice receiving the two drugs 
mixed in the above proportions lived 6, 7, 9, and 10 days, an average 
of 8 days,^ or, in other words, lived the same length of time as the 
acetanilide controls. Another series fed on slightly larger amounts 
of salicylic acid (0.030 gram with acetanilide 0.050 gram per cake) 
a Mice are especially sensitive to changes in temperature, and the unusual results 
of this series may be explained upon these grounds. During the course of the experi- 
ments the mice were moved into a room where part were much closer to a steam 
radiator than others, and it is very likely that those kept in the warmest position 
lived the longer. 
bThe control mice fed on 0.030 gram salicylic acid lived for 50, 62, and 66 days. 
