DEVELOPMENT OF BIOLOGY 



459 



dissecting with untiring patience and skill a remarkable series of 

 animal types, as well as reconstructing extinct forms from fossil 

 remains. Aside from the facts accumulated, probably his greatest 

 contribution was making concrete the distinction between homol- 

 ogous and analogous structures. This has been of the first impor- 

 tance in working out the pedigrees of plants as well as of animals ; 

 though Owen himself took an enigmatical position in regard to 

 organic evolution — not unlike that of the great teacher and in- 

 vestigator of zoology in America, Agassiz (1807-1873), but quite 



Fig. 298. — Thomas Henry Huxley. 



different from that of Huxley (1825-1895), his famous English 

 contemporary comparative anatomist. (Figs. 227, 298, 299.) 



3. Physiology 



The functions of organisms were discussed by Aristotle with his 

 usual insight, though, as might be expected since physiology is 

 more dependent than anatomy upon progress in other branches of 

 science, with less happy results. Similarly Galen was hampered in 

 his attempt to make physiology a distinct department of learning, 

 based on a thorough study of anatomy, and the corner-stone of 

 medicine; though fate foisted upon uncritical generations through 

 fifteen centuries his system of human physiology. 



Neither Vesalius nor Harvey made an attempt to explain the 

 workings of the body by appeal to so-called physical and chemical 



