310 
obtained from the Illinois Central Railway division office through the 
courtesy of Supt. W. Atwill, and from Mr. C. E. Cox, a former civil 
engineer. By means of these larger-scale maps I was able to: indicate 
practically every possible breeding-place of mosquitoes which would be 
likely to affect the people of Carbondale. Although winds may carry mos- 
quitoes for a distance of several miles (as will later be shown in the case 
of Anna and Jonesboro) it is usually believed that mosquitoes do not fly 
over half a mile from their breeding-places. Most of the places ex- 
amined are within half a mile of the edges of town. (Maps, pp. 312, 313.) 
Examinations and Collections—Collections of larvae and pupae were 
made once, and sometimes twice, a month during the breeding seasons of 
1918 and 1919 (with the exception of September, 1919) and were bred 
to the adult for identification. The wigglers were scooped up with a 
small strainer with a handle and a screen of about twenty meshes to the 
inch. They were removed with a small soft brush, such as is used in 
water-color work, and put temporarily into tin pill-boxes together with 
a little of the same water in which they were found. The contents of 
the pill-boxes were later emptied into glass jars in the insectary and more 
water with aquatic vegetation and some of the mud from the bottom was 
poured into the jars to furnish food and natural conditions. I usually 
secured this water from some one or two breeding-places which seemed 
to produce mosquitoes abundantly, taking care to exclude mosquito larvae 
and any animals which might be predaceous upon the mosquitoes. Notes 
were made as to the presence and abundance of the malarial and non- 
malarial mosquitoes in each breeding-place examined, and the species 
were later determined by Dr. C. P. Alexander and Mr. J. R. Malloch, 
of the Natural History Survey. 
The Anopheline and Culicine larvae (carriers and non-carriers of 
malaria) are readily distinguished by the positions which they take while 
resting at the surface of the water, the Anophelines lying parallel to the 
surface while the Culicine larvae hang down at an angle of about forty- 
five degrees, with only their long breathing tubes touching the surface. 
The pupae are more difficult to distinguish and will not be discussed. 
The adults of our Anopheles are easily distinguished from Culex and 
other genera by the spots on the wings, the Culicine wing being clear. 
The palpi of the female are longer in Anopheles than in Culex. The body 
of the Anopheline adult forms an angle with the surface upon which it 
rests, while that of the Culicine is parallel to the surface. 
BREEDING-PLACES 
Mosquito breeding-places at Carbondale are typical of those in many 
other towns. In the following description I am grouping them in classes 
which will be readily recognized by residents of other places. The breed- 
ing-places were numbered, as shown on the maps (pp. 312-313), to facili- 
tate the making of records. Plates XXXI—XXXYV illustrate a few of 
the situations. 
