234 Qulicifuf/es 
Table IV. 
Total No. 
Number of 
experiment 
Initial of 
experimenter 
Number 
of bites 
Percentage of 
total bites 
Initial of 
experimenter 
Number 
of bites 
Percentage of 
total bites 
of bites 
recorded 
1 
A.B. 
10 
17% 
G.T. 
49 
83% 
59 
2 
A.B. 
3 
8 
G.T. 
36 
92 
39 
3 
A.B. 
37 
84 
H. 
7 
16 
44 
4 
A.B. 
16 
38 
I. 
27 
62 
43 
5 
A.B. 
23 
47 
J. 
26 
53 
49 
6 
A.B. 
16 
25 
K. 
50 
75 
66 
7 
A.B. 
6 
30 
L. 
14 
70 
20 
8 
G.T. 
6 
14 
K. 
38 
86 
44 
9 
G.T. 
8 
30 
J. 
19 
70 
27 
10 
G.T. 
62 
78 
H. 
17 
22 
79 
11 
G.T. 
27 
77 
I. 
8 
23 
35 
12 
G.T. 
4 
25 
M. 
12 
75 
16 
Out of the six persons who assisted in these trials two, owing to lack of 
opportunity, made the trial with one of the experimenters only, L. with 
A. B. and M. with G. T. and their records are consequently discarded when 
making a final comparison between the resistant powers of A. B. and G. T. 
For this purpose the percentages of the results may be arranged as under. 
The two trials between A. B. and G. T. are averaged and treated as a single 
trial. 
Table V. 
A.B. 
A.B. 
G.T. 
12-5 
G.T. 
87-5 
— 
H. 
16 
22 
I. 
62 
23 
J. 
53 
70 
K. 
75 
86 
206 
201 
H. 
I. 
J. 
K. 
Totals 
84 
38 
47 
25 
206-5 
78 
77 
30 
14 
286-5 
Totals of the percentage of bites received by the four experi¬ 
menters H., I., J. and K. in trials with A.B. and G.T. 
respectively. 
From this it would appear that in the comparison of A. B. and G. T. alone 
the ratio of the mosquitoes’ preference for G. T. is roughly 7 to 1, but if the 
question is fudged in relation to the other four experimenters in combination 
with A. B. and G. T. the ratio of preference is less than 3 to 2; while, if the 
comparison is made through the relation of the four persons H., I., J. and K. 
only, leaving the direct tests between A. B. and G. T. out of account, the 
preference is not far from parity. It is probable that this* divergence in 
result, according to the inclusion or exclusion of some of the experimenters, 
is not a matter of pure chance, but the effect of the mosquitoes* preference 
being swayed by more than one factor; for instance, if the presence of a moist 
skin is one factor the temperature of the skin may constitute another, and the 
intensitv or other characteristic of the odour arising from the skin vet another 
factor. 
