LINNJEUS AND HIS INFLUENCE 61 



incisive inquiry, the cells composing the tissues 

 became the object of investigation. These progres- 

 sive steps of analysis, from the organism, to organs, 

 to tissues and cells finally culminated in the recogni- 

 tion of protoplasm the actually living substance of 

 all animal (and plant) organization. 



Knowledge of the physiological side of animal life 

 had a parallel development. In the period of Lin- 

 naeus, the physiology of the organism was pursued 

 by Haller and his school; following this the physiol- 

 ogy of organs and tissues was advanced by J. Muller, 

 Bichat and others. Later, Virchow investigated the 

 physiology of cells, and Claude Bernard the chemical 

 activities of protoplasm. 



