25 
resents was conducted in September, 1914, under the direction of 
Surg. R. H. von Ezdorf, in charge of malaria investigations of the 
Public Health Service until his death in September, 1916, and be 
also personally supervised the microscopical examinations tabulated. 
Table No. VII. —Showing persons examined in September, 1914. 
Age. 
* 
Number examined. 
Number infected. 
White. 
Colored. 
Total. 
White. 
Colored. 
Total. 
M. 
F. 
M. 
F. 
M. F. 
M. 
F. 
Under 1 year. 
1 
2 
3 
1 
1 
lto3... 
26 
22 
48 
17 
8 
25 
4 to 5. 
1 
42 
37 
80 
i . 
18 
13 
32 
6 to 9. 
1 
73 
66 
140 
30 
34 
64 
10 to 14. 
1 
1 
119 
94 
215 
1 1 
42 
30 
74 
15 to 19. 
92 
86 
178 
42 
35 
77 
20 to 29. 
3 
1 
200 
196 
400 
2 . 
73 
85 
160 
30 to 39. 
1 
1 
112 
86 
200 
1 . 
44 
44 
89 
40 and over. 
1 
242 
151 
394 
94 
62 
156 
Not stated. 
4 
3 
8 
2 
2 
4 
Total. 
7 
8 
907 
743 
1,666 | 5 1 1 
363 
313 
682 
Summary of results of blood examinations — September, 1914. 
Total number of persons examined_1. 666 
Positive for malaria_ 682 
Malaria index_per cent_40. 9 
Types: 
Tertian (857 cases)_do_ 52.3 
Subtertian (319 cases)_do_ 47.7 
Mixed cases (6) not considered in the percentage above. 
Number of subtertian gametocyte carriers_ 86 
Percentage of subtertian gametocyte carriers_per cent_26.4 
In comparing the data obtained in September, 1914, with those 
obtained in February and March, 1915, it is evident that the malaria 
index existing during the winter months remains little altered. It is 
patent, at least, that recoveries following treatment do not favorably 
influence the important bearing of the gametocyte carrier. It will be 
observed that not only is there a relative increase in the number of 
subtertian gametocyte carriers, but an actual increase, the percentage 
being raised during latency from 26.4 per cent to 32.8 per cent, and 
the total number is increased from 86 to 122. It must be observed, 
however, in this connection, that probably a smaller percentage of 
the winter carriers harbored suitable numbers of gametocytes to be 
capable of infecting Anopheles mosquitoes. 
Of the total number of 1,184 persons examined in February and 
March, 1915, it is possible to draw certain comparative deductions 
from a representative group of 103 carriers of all ages distributed 
among 11 plantations. The persons in this group were selected be- 
