THE CONQUEST OF DISEASE 



perimenting in the physiology and pathology 

 of animals is all applicable to man. Sometimes 

 the value of this work appears in most unex- 

 pected quarters. When Ross discovered that 

 the mosquito is the host that contains the plas- 

 modium of malaria, his discovery connected 

 two widely separated fields of biologic interest. 

 The pathology of malaria in man had been 

 well studied and was a matter of scientific rec- 

 ord; and the biology of the mosquito, its ana- 

 tomy, physiology, life history, and habits had 

 been well worked out by the biologists. Now 

 these two fields of knowledge are connected by 

 the minute plasmodium, and the mosquito im- 

 mediately comes into intensely practical im- 

 portance with reference to man. 



The flies and worms and many other lower 

 animals are being connected intimately with the 

 life of man; and the biologic sciences are be- 

 coming more closely knit together. Not only 

 this, but the studies which the biologists are 

 making in cellular generation, regeneration, 

 mutation, and pathology among the primative 

 animal forms are translatable to other animals 

 and to man. Every biologic laboratory is 

 an institution of experimental animal research. 



By animal experimentation, from the more 



6 



