28 The Science of Life. 



Galen had only been permitted to dissect monkeys, 

 and human anatomy was largely conjectural until Ves- 

 Rise of alius placed it on a sure basis in the sixteenth 



Comparative century. This was not only important in 

 Anatomy. itself, but it raised a standard of accuracy 

 which gave a stimulus to the zoological anatomist a 

 stimulus which has often been repeated in the history of 

 the science. Many zoologists have acknowledged their 

 indebtedness to their discipline in human anatomy. 



In the encyclopaedic period anatomical researches 

 began to become common, monographs on different 

 groups were published, and huge treatises, like Gesner's 

 Historia Animalium (1551-1558), with 4500 folio pages, 

 made their appearance. In these, however, there seems 

 to have been rarely any deep morphological note; there 

 was dissection but without comparison, analysis but 

 without synthesis. In Belon's Birds (1555) there is " a 

 comparison of the skeletons of Bird and Man in the 

 same posture, and as nearly as possible bone for bone"; 

 and in 1645 Severinus published his Zootomia Democri- 

 tcea, "the first book devoted exclusively to the general 

 subject of comparative anatomy ". 



In the seventeenth century Harvey discovered the 

 circulation of the blood (1616, announced 1628), and 

 carefully dissected the heart; some of the early micro- 

 scopists, e.g. Malpighi and Swammerdam, turned their 

 attention to the structure of the lower animals ; and the 

 progress of classification in the hands of Ray and Lin- 

 naeus reacted on anatomy. 



In the eighteenth century there were some great 

 workers more or less on comparative lines. John Hunter 

 dissected and observed with untiring industry, and Vicq 

 d'Azyr struck an even clearer morphological note. 



Georges Cuvier (1769-1832) was not only great in 

 himself and his work, but in his school, for he dominated 

 Cuvier and most of the zoological work of the first 

 Correlation. na jf o f the nineteenth century. He dissected 

 many animals which had not previously been touched; 

 he insisted on the anatomical basis of classification ; 

 and he recognized that there were several divergent 

 types of structural architecture (Vertebrate, Molluscan, 



