The Cells of the Body 9 



primitive assimilating power would simply be 

 specialized and intensified, and the animal 

 would have risen to a higher grade of being. 



It would not be difficult, did space permit, to 

 trace the manner in which, as we pass upward 

 in the animal series, certain groups of cells be- 

 come more and more elaborate in structure as 

 they assume higher and more specialized ca- 

 pacities. We cannot tarry for this, but will 

 glance for a moment at the exhibition of this 

 principle in the development of man. In man, 

 too, life commences in a single cell called the 

 ovum; a cell which, though harboring poten- 

 tialities of the highest order, in many respects 

 greatly resembles our little denizens of the 

 water. This cell, under suitable conditions, 

 divides and subdivides, forming a little cluster 

 of cells all looking alike. Then these cells 

 arrange themselves in layers; some of them 

 assume special forms as they increase in num- 

 ber, and develop special capacities, and group 

 themselves to form the various tissues and 

 organs of the mature body, which finally is 

 formed of a grand community of co-ordinated 

 groups of cells, some of which have acquired 



