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and hunt, or to look after their farms, and that they may thus contract 
malaria away from the towns. 
There are, however, other much closer, and probably more impor- 
tant sources of malaria. In both Anna and Jonesboro small streams run- 
ning in and close to town contained Anopheles in considerable numbers, 
and I do not doubt that these are among the chief sources of mosquitoes. 
Ponds in the fair-grounds of both towns and two other small pools exam- 
ined, also showed Anopheles, and it is quite likely that such places furnish 
most of the mosquitoes in the vicinity. 
Survey Work at Scott FIeLp, BELLEVILLE 
Upon request of Captain Bayliss, principal medical officer at Scott 
Aviation Field, investigations of the mosquito situation around the camp 
were made in the summer of 1918. This field has been located very close 
to a large swamp, which at one point was only a quarter of a mile away. 
There was an abundant growth of vegetation to shelter mosquito larvae, 
and those of Anopheles were found in considerable numbers. The ordi- 
nary swamp-land growth (Fig, 16) of trees, brush, and weeds was quite 
rank, and arrowhead especially abundant. Owing to an excessively dry 
summer the swamp practically dried up later, and no further examina- 
tions of it were made. 
Within a few rods of the field boundary is a slow stream (Fig. 17). 
This was breeding Anopheles, and they were even more abundant a little 
later when the stream was reduced by the drouth to a series of pools. 
There was no current at that time to hinder development, and there was 
grass enough around the edges for protection. 
ScouTING WorK IN OTHER PLACES 
General scouting work was done in and around Thebes and Cairo, 
and in Williamson county, and additional types of breeding-places were 
observed in these places. Some inquiries were made as to the extent of 
malaria, and some maps were made. 
ConTROL MEASURES 
1. Drainage—Beyond a doubt, drainage is the most effective meas- 
ure for the control of mosquitoes, with the exception of those living in 
running streams; and the first step in a clean-up campaign is the elimina- 
tion of standing water. 
At Carbondale a special effort was made to bring this subject to 
the attention of those in charge of property containing standing water. 
The opinion of the surveyors that the cattail swamps north of town could 
be drained into a tributary of Crab Orchard Creek by a ditch a little over 
a quarter of a mile long was laid before the division superintendent of the 
Illinois Central Railroad Company at Carbondale. 
