Tlie Organism and its Protoplasm 131 



\Vc know that witli reduction in dimensions nature changes 

 the means bj which the energies of the inorganic world are 

 made serviceable in the organism. But with the exception of 

 the differences conditioned by this fact, and with the ex- 

 ception of tlie less number of constituting parts, we have 

 no right to liold one of these smaller organisms as less 

 ingeniously constructed than one of another or greater di- 

 mensions, and this consciousness we ought to bring not only 

 to the investigation of the smallest animals, but likewise to 

 the investigation of plant and animal cells. We may always 

 see in the cell a small animal body, and ought never to 

 lose sight of the analogies which exist between it and the 

 smallest animal forms." ^^ 



Characteristic Organization in All Cells 



But it is in connection with the problem of the more de- 

 tailed structure of all parts of the cell, membrane, nucleus, 

 and cell-body alike, that this investigator's conclusions and 

 attitude of mind are most fully revealed, his great point 

 being that there must be far more of organization in the 

 cell than microscopes reach. "What right have we to be- 

 lieve," he says, "that in our scheme we have exhausted the 

 organization of the cell.^ Is it a ground for such an as- 

 sumption that we can perceive no further details in the 

 relatively giant retinal image given us by our present high 

 magnifications? . . . Shall we conceal from ourselves the 

 fact that many circumstances limit the field of our mi- 

 croscopical determination?" ^^ 



In \'iew of the fact that later speculative biologists have 

 appealed to Briicke's contention that there must be cell or- 

 ganization beyond that revealed by the microscopes, in sup- 

 port of their fancied "ultimate biological units," it should 

 be emphatically pointed out that not only does Briicke's ar- 

 gument not give passive sanction to such hypotheses, but 



