4 FISHES IN RELATION TO MOSQUITO CONTROL. 
become better understood thereby and that the observations reported 
will be of help to those who in the future may wish to employ this 
useful little fish in antimalarial work. 
GENERAL TOPOGRAFHY OF AUGUSTA AND SURROUNDING TERRITORY. 
The city of Augusta is situated on the Savannah River, in a low 
and rather flat valley, and because of the recurrence of floods and 
the consequent danger to life and property, a levee was constructed 
between the river and the adjacent territory. However, there is a 
considerable elevation westward or toward the “Hill” section of the 
city, beyond which lies Camp Hancock. The one-mile belt surround- 
ing the city extends across the Savannah River and includes a sec- 
tion of South Carolina. There were many swamps in this rather flat 
territory, but fortunately most of these were drainable and have 
been eliminated by the United States Public Health Service in coop- 

Gambusia affinis (male). 
eration with the authorities of Richmond County and the city of 
Augusta. In addition to the swamps there are many ponds. Nearly 
all of these are artificial and they vary in size and depth. Drainage, 
in most instances, is impracticable, if indeed not impossible. The 
majority of these ponds were made in the manufacture of brick, an 
industry which was started in Augusta in about 1808. The clay pits 
made by these manufacturing concerns, because of the flat nature of 
the country, soon become filled with water. Sometimes after hard 
rains the water is pumped out and digging is resumed in the old pits, 
but frequently the digging machines are moved. Thus new ponds 
are being formed constantly. There are more than one hundred of 
these clay pits in the territory under protection, and in addition there 
are a number of ponds or lakes which were made for the purpose of 
furnishing a water supply, or for water power. 
These ponds present a variety of conditions. Some of them are 
very old and have become partly filled with sediment; the shores 
are often gently sloping oe much aquatic vegetation is present. 
Such ponds usually furnish an ideal environment for the support of 
mosquito larve. The newer ponds generally have steep shores; 
