4 THE ART OF MORPHOLOGY 



of organised bodies, is usually comprehended in 

 the three faculties of human anatomy, zoologi- 

 cal anatomy (zoology), and vegetable anatomy 

 (botany). Each of these primary disciplines 

 introduces the student to several paths of learn- 

 ing, e.g., topographical anatomy (anatomy sensu 

 stricto), physiological anatomy (physiology or the 

 treatment of structure in relation to function), 

 histological anatomy (histology or microscopic 

 anatomy), ontogenetic anatomy (embryology), 

 and philosophical anatomy (morphology). These 

 are what Owen (1866) called the ways of 

 anatomy. 



Histology, the anatomy of the constituent 

 parts or tissues of organs, is investigated by 

 microscopical and microchemical methods which 

 were pioneered by Xavier Bichat whose work, 

 " Anatomic ge"nerale appliquee a la Physiologic " 

 (1801), preceded by more than a quarter of a 

 century the enunciation of the cell-theory. This 

 theory laid the foundation of a great part of 

 modern biological research, and it is a significant 

 circumstance that it was published in the decade 

 which witnessed the death of Cuvier (1832). 

 It teaches that the ultimate units of all the 

 tissues of an organism consist of nucleated proto- 

 plasmic bodies, conventionally termed cells, which 

 are derived by repeated cell - division from a 

 primordial fertilised egg-cell ; and it also forms 

 the basis of the subdivision of the animal 



