4 o 4 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



tremendous financial loss resulting from the quarantine and 

 suspension of business which, until recent years, always fol- 

 lowed an outbreak of yellow fever in any region. 



Again we might consider the great loss of time and energy 

 that is occasioned by malaria in many regions. A man's 

 producing capacity may be reduced 50 to 75 per cent, for a 

 number of years because of this disease. This, of course, most 

 seriously retards the development of the malarial regions, 

 regions that might otherwise be producing millions of dollars 

 where they now produce only hundreds of thousands. It is 

 not conceivable that we can make any estimate in dollars 

 and cents of the great bodily and mental suffering entailed 

 as a result of some of the diseases that are carried by insects 

 and of the hundreds of thousands of deaths that occur annually 

 from these diseases. Yet these are by far the most important 

 factors to be considered in estimating the economic importance 

 of insects, and the work that is being done along the line of con- 

 trolling the insects that carry disease germs is the work that 

 most demands the co-operation and support of every citizen. 



In no country in the world are the forces that are fighting 

 insect pests so well organized as they are in the United States. 

 The federal government maintains a large and very effective 

 Bureau of Entomology employing more than one hundred 

 men most of whom devote their whole time to the study of the 

 insect pests and methods of controlling them. Nearly all 

 states have their State Entomologists, who may or may not be 

 connected with the state agricultural colleges and experiment 

 stations, and many other horticultural officers and inspectors 

 who devote a large part of their time to the study and control 

 of insects. 



We cannot fight insects successfully without some knowl- 

 edge of their structure and habits and life-history. More 

 than this, we must know something of their relation to other 

 insects and other animals. So the study of economic 

 entomology includes attention to systematic and morphologic 

 and ecologic entomology. It is a much more comprehensive 

 study than it is perhaps popularly supposed to be. 



Government entomologists really devote a large part of 



