THE PRO TO PLASMA AND THE CELL. \\ 



tinguish the individual ones. It is only on the death of the 

 ciliated cell, when these oscillations are retarded, that they 

 can be counted. We now know that these fine ciliae are pro- 

 toplasma threads, and that their movements fall within the 

 vital sphere of that remarkable substance. The rapid work 

 of these small hairs and the sluggishness of ordinary proto- 

 plasm, it is true, present a difference which is still inexplicable. 



Where there is motion in the domain of animal life, there 

 is also sensation. Have the cells, the vitalized, minimal cor- 

 ner-stones of our bodies, the latter capacity ? We may affirm 

 this unreservedly. 



When these changeable figures, as they were represented 

 in our Fig. 15, are subjected to a weak electrical irritation, 

 they rapidly return to the spherical form, to subsequently 

 recommence the old play of forming processes. 



Every organism, even the smallest and most simple, has a 

 transmutability ; that is, it gives off altered unserviceable par- 

 ticles of matter, it receives into itself new matter, and trans- 

 forms it into the constituents of its own body. The mass of 

 the organism then increases, it grows. 



All this happens, likewise, to the cell. The perception of 

 these vital actions is rendered difficult by the smallness and 

 the obscure existence of our structures. That the cells grow 

 may be abundantly shown and with the greatest certainty, as, 

 for example, in the fat and cartilage tissues. That they take 

 up and transmute matter ; that is, make it something chemi- 

 cally different, may also be perceived without trouble. Melanin, 

 , the black pigment we mentioned above, is wanting in the 

 blood. It is formed by the cell (Fig. 9). Choleic acid salts 

 and biliary pigment, the former, at least, certainly not present 

 in the blood, are productions of the living hepatic cell. The 

 latter presents us, furthermore, with a striking example of the 

 exchange of matter. Both the substances just mentioned 

 appear later as ingredients of the bile. We could readily cite 

 many such occurrences, but these few remarks may suffice ; 

 they show, at least, the coming and going of the materials. 



The law of destruction adheres like a curse to the heels of 



