92 PROC. ENT. SOC. WASH., VOL. 20, NO. 5, MAY, 1918 



Division of Labor 



Necessarily no one man or group of men can hope to become 

 familiar with the entire subject. The field is tremendous and 

 requires many types of specialists cooperating closely in order that 

 a single disease complex be thoroughly understood. 



When we consider that the different diseases, the different in- 

 sects, and the different animals are inextricably interrelated we see 

 the great necessity of concerted action among all sciences engaged 

 in the study or prevention of disease. The physician finds that 

 he must principally devote his attention to the diagnosis and 

 treatment of the diseases brqught to his attention, but is often able 

 to carry his studies farther. The protozoologist, the bacteriolo- 

 gist, and the helminthologist, must follow out the complete life 

 cycle of the organisms which they have studied through all hosts, 

 invertebrate and vertebrate. The entomologist must study the 

 life history and control of the insect, the relationships of the insect 

 to the host and the relationships of the parasites in the insect to 

 the diseases of the host. The sanitarian must understand all 

 those things worked out by the entomologist, protozoologist, 

 bacteriologist, helminthologist, and physician and be able to 

 devise ways and means of accomplishing the recommendations of 

 these specialists. There can be no hard and fast line delineating 

 the energies of any one group of investigators. Each group of 

 specialists must necessarily review a part of the subjects which 

 appears to belong to another group of specialists in order that they 

 may thoroughly understand their own work. 



The Phases of Medical Entomology. 



We have to deal in this discussion with the entomological view- 

 point in medicine and sanitation. The entomologist may divide 

 his activities into three distinct groups the biological and eco- 

 logical, the medical and veterinary, and the sanitary. Under the 

 biological and ecological phases of medical entomology we place 

 the studies of the life history of insects which may in some way be 

 related to the transmission or causation of disease. 



The medico-veterinary phase of the question involves the study 

 of the insects in direct relationship to the vertebrate hosts, and 

 necessarily must include studies of the transmission of disease by 

 insects for it is obvious that only one trained in the study of insects 

 can adequately perform experiments in disease transmission. The 

 very first necessity in such experiments is the ability to rear the 

 insects and to keep them alive during the period of experimenta- 

 tion. It is fortunate when the person who does this experimenta- 

 tion is not only a trained entomologist but also is trained in the 

 subjects of medicine, protozoology and bacteriology. In fact, we 



