BODY TEMPERATURE OF MICE 327 



sexes. If we reject the less reliable (starred) figures in the table, 

 we have six cases where such a comparison is possible among the 

 males, and an equal number among the females. The mean rise 

 in temperature for the former is 1.55°C., for the latter 0.47°. 

 If we include the rejected figures (4 for the males and two for 

 the females), the former average becomes 1.51°, the latter 0.76°. 

 Only a single instance of a fall in temperature between the two 

 tests is recorded. 



2. When the interval between the two tests was more than 

 one hour (eighty to one hundred and thirty-five minutes), there 

 was much less agreement among the results. In 15 comparisons 

 among the male mice, there was a rise in 10 cases, and a fall in 

 4 cases. The mean rise was 0.53°. Among the 8 available figures 

 for females 2 show an increase and 5 a decrease, there being a 

 mean decrease of 0.05° (i.e., no significant change). 



3. When more than two tests were made during the same day, 

 there was a mean fall of 1.22° between the second and third tests 

 for 5 males (table 9), and a mean fall of 0.4° for two females 

 (table 7). The time interval was one hour for the former, fifteen 

 to thirty minutes for the latter. 



From the foregoing considerations, it is plain that the most 

 serviceable temperature data in my records are those which 

 resulted from the first determinations for the day. These are 

 consequently the ones which have been employed exclusively in 

 the comparisons between the warm-room and cold-room animals. 



Certain other conditions besides the excitement or irritation 

 resulting from these tests were of probable influence in produc- 

 ing changes of temperature among the mice. When the animals 

 were transferred to new and unfamiliar surroundings they were 

 nearly always seen to be agitated for some time thereafter, and 

 it is likely that this agitation resulted in a rise of body tempera- 

 ture. Referring again to table 9, it will be seen that the mean 

 temperature of these 5 mice, on the afternoon of March 31, 

 shortly after a transfer to new boxes^^ was 37.98° (thirty seconds) 

 or 38.30° (maximum) Unfortunately, we have no afternoon 



1^ My object, indeed, in changing the cages in the present instance, was to test 

 this very point. I should have taken the second reading on the afternoon of the 

 following day. 



