322 
wintered eggs; but this may be due to the fact that summers are drier, 
and favorable pools rarer, than they are in the North.” 
SurvEY Work IN MturPHYSBORO 
My procedure in Murphysboro was similar to that at Carbondale. 
The leading physicians whom I interviewed gave two hundred to four 
hundred cases of malaria as their estimate for an average year. As the 
population is about eight thousand, this would mean that 2% to 5 per 
cent. of the inhabitants are treated for malaria annually. A map of the 
township was traced, and all possible breeding-places were located; and 
examinations and collections were made, but, owing to other occupations, 
not very continuously throughout the season. 
BREEDING-PLACES 
Class I, Cattail Swamps—No breeding-places of this type are near 
enough’ to affect Murphysboro. A large number which are in some re- 
spects similar, I am placing in a separate class (No. IX). 
Class II, Marsh——Not found in Murphysboro or immediate vicinity. 
Class III, Ponds——Railroad embankments very often form ponds by 
damming up water. One such pond, located close to the Brown shoe fac- 
tory, I found to be a breeder of Anopheles. Pleasure and amusement 
parks may be mosquito-breeding grounds; and a few small ponds in the 
city park in Murphysboro contain Anopheles. In a ravine very close to 
the high school is a representative of this type (Fig. 11). 
Class IV, Roadside Ditches —This type is not noticeable in Murphys- 
boro. 
Class V, Streams——Running through the city park is a slow stream 
(Fig. 12) with banks well covered with grass and affording ideal breeding 
conditions for Anopheles mosquitoes. The fact that the only park in 
town includes this stream is deplorable, as it probably*accounts for much 
of the malaria. It should be remembered that a park is very often vis- 
ited for picnics in the evening, when malarial mosquitoes bite. , 
Class VI, Open Drains—One drain in the north end of town is re- 
sponsible for the production of part of the Anopheles mosquitoes in 
Murphysboro. 
Class VII, Lakes—The situation at Carbon Lake, belonging to the 
Country Club of Murphysboro, is very similar to that at Thompson’s Lake 
near Carbondale. Stecher’s Lake is much more likely to breed Anopheles, 
especially because of its grassy edge (Fig. 13). Under the culvert at 
onpne of the lake I was often able to make large collections of Anopheles 
adults. 
Class VIII, Temporary Flooded Land.—This type is caused by over- 
flow of the flats of the Big Muddy River, at the south edge of town. The 
high water lasts, however, for so short a time that I doubt whether many 
of the mosquitoes of Murphysboro can be traced to this source. 
