362 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1926 
But prevention is always better than cure. The surest way to 
put an end to malaria ravages is to extirpate the mosquitoes. In 
rainy regions this is hard to do, but the worst kinds of mosquitoes 
belong to the Tropics or to regions just north of the Tropic of Cancer. 
They are often virulent in swamps, but apparently equally so in dry 
regions in ponds and puddles not connected with jungles. Thus 
certain districts in the Ukraine, in Anatolia, in Macedonia, in Greece, 
and in southern Italy have been historically notorious for malarial 
diseases. ‘The Campagna of Rome, “ Five Fingered Sparta,” and 
probably Mycene, the original source of Hellenic culture, are clas- 
sical examples of the undoing of populations by mosquitoes. The 
fading of “the glory that was Greece,” due primarily to her suicidal 
wars, must have been in large part also the work of mosquitoes. I 
know personally something of their havoc in Macedonia and I am 
told that in regions about the Black Sea, Ukrainia, and Anatolia, 
the plague is still more virulent. 
Near Salonika in Macedonia the Turkish authorities built an agri- 
cultural school and experimental station near the sea, at the foot of a 
marshy valley. This was found to be uninhabitable on account of 
the poisonous mosquitoes. 
The work of our Army surgeons, Dr. Walter Reed, Dr. Jesse 
Lazear, Dr. James Carroll and their associates, in cleaning up fever- 
stricken Havana, is a classic in medicine. This has been followed up 
by the drastic purification of Panama, Vera Cruz, Guayaquil, and 
other poisoned ports, the work of Gen. W. C. Gorgas and others. 
ais get rid of mosquitoes is now one of the most important elements 
“ preventive medicine” or sanitation. 
as how shall this be done? There are three general lines of 
attack—to get rid of their breeding places, to cover these with oil, 
or to bring in an enemy which will devour their eggs and young. 
In this connection I may refer to a plan in Texas to build and pro- 
tect bat houses, as bats in the night devour mosquitoes as well as 
other insects. But a colony of bats can operate on a very small 
scale only, and I need not refer to them further. 
Pools and other breeding places can often be drained or filled up 
with sand or rock. As all mosquitoes lay their masses of eggs in 
quiet or stagnant water, in which they hatch, a layer of petroleum 
over the water will smother their larve or “ wigglers ” and will also 
prevent the winged insect from escaping. But there are many 
bodies of water in which neither of these methods can be used. In 
such cases, the mosquito-eating fishes are the best resort. A good 
many kinds of little fishes will eat mosquito eggs or larve when 
they find them convenient. Sticklebacks, young trout, some min- 
nows, even gold fish do this to some extent. But what is needed is a 
