14: HANDBOOK OF PHYSIOLOGY. 



which the original cell may be supposed to discharge, and the various 

 properties it may be supposed to possess, are divided up among various 

 groups of resulting cells. The work of each group is specialized. As a 

 result of this division of labor, as it is called, these functions and prop- 

 erties are, as might be expected, developed, and made more perfect, and 

 the tissues and organs arising from each group of cells are developed also, 

 with a view to the more convenient and effective exercise of their func- 

 tions and employment of their properties. It would be out of place 

 here to discuss the question as to the exact manner in which a property 

 or function, rudimentary in a low form of animal life, is found to be 

 highly developed as we pass up the series ; neither is it our province to 

 discuss the very complicated subject of the relationship of man to other 

 animals, and of these to one another. 



Having now briefly indicated the close connection which exists be- 

 tween Human physiology and Biology in general, we are better prepared 

 to commence the study of the former as constituting a part of a great 

 whole. 



The next two chapters will be devoted to a consideration of the 

 minute structure, or the histology (IGTOS, a tissue or web) of epithelium 

 and the connective tissues. 



