EPOCHS IN BIOLOGICAL HISTORY 389 



glands. Skilled in anatomy but with prime interest in physi- 

 ology, his lasting contribution lies in his dependence upon the 

 microscope for the solution of problems where structure and 

 function, so to speak, merge. This is well illustrated by his 

 ocular demonstration of the capillary circulation in the lungs, 

 which is not only his greatest discovery but also the first 



FIG. 200. Marcello Malpighi. 



of prime importance ever made with a microscope, since 

 it completed Harvey's work on the circulation of blood. 



D. THE DEVELOPMENT OF THE SUBDIVISIONS OF BIOLOGY 



The microscopists taken collectively created an epoch in 

 the history of biology, so important is the lens for the ad- 

 vancement of the science. Broadly speaking, we find that 

 its development along many lines during the eighteenth and 

 particularly the nineteenth century went hand in hand with 

 improvements in the compound microscope itself and in mi- 

 croscopical technique. Again, the microscopists in general 

 and Malpighi in particular opened up so many new paths of 



