426 Mosquitoes and Malaria 
If 1 — ii" = 0, /i = 0 for = 1 — - — r and is therefore fractional : also if w = 0 
the case reduces to that in which there is an entire absence of mosquitoes : hence 
in this enquiry 1 — R^^Q and we must proceed with Equation (ii). This may- 
be written 
_ 1 _ 1 
m p' 
Now when n > 1 
, ,^ , •100343 
log (1 - r) = . 
Hence by giving a series of values to m we may find the number of anophelines 
corresponding to any stable population. 
Taking p = 1000, m — 5, we get 
r = -2 --001 = -199, 
.-. log (1 -?■) = - -096367, 
•100343 
•096367, 
and 71=104125 
But 
_ am 
''-192p' 
192 X 1000 X 1 04125 
= 39984. 
Similarly we get the table of corresponding values of m and a for stable 
populations given below. 
TABLE A. 
Table of Gor?-espo tiding Values of m and a for a Stable Population 
of a Thousand. 
a 
a 
a 
5 
39984 
150 
520.32 
600 
110914 
8 
41886 
175 
53648 
650 
126720 
10 
42553 
200 
55339 
700 
147892 
15 
43539 
250 
59062 
750 
177525 
20 
44148 
SOO 
63308 
800 
221752 
25 
44605 
350 
68193 
850 
295897 
50 
46251 
400 
73883 
900 
444118 
75 
47662 
Ji50 
80612 
950 
885583 
100 
49069 
500 
88680 
125 
50520 
550 
98534 
