<iN TIIK PHYSICAL P.ASIS <F LIFE in 



successfully take on the function of feeding, mov- 

 ing, or reproducing apparatus. In the highest, on 

 the contrary, a great number of parts combine 

 to perform each function, each part doing its 

 allotted share of the work with great accuracy 

 and efficiency, but being useless for any other 

 purpose. 



On the other hand, notwithstanding all the 

 fundamental resemblances which exist between 

 the powers of the protoplasm in plants and in 

 animals, they present a striking difference (to 

 which I shall advert more at length presently), in 

 the fact that plants can manufacture fresh proto- 

 plasm out of mineral compounds, whereas animals 

 are obliged to procure it ready made, and hence, in 

 the long run, depend upon plants. Upon what 

 condition this difference in the powers of the two 

 great divisions of the world of life depends, nothing 

 is at present known. 



With such qualifications as arise* out of the 

 last-mentioned fact, it may be truly said that t he- 

 acts of all living things are fundamentally HIM-. 

 Is any such unity predicable of their fojm_s ? Lrt 

 us seek in easily verified facts for a reply to this 

 question. If a drop of blood be drawn by pricking 

 one's finger, and viewed with proper precautions, 

 and under a sufficiently high microscopic power, 

 then- will be seen, among the innumerable multi- 

 tude of little, circular, discoidal bodies, or cor- 

 puscles, which float in it and give it its colour, a 



