MYSTERY OF THE CELL 3G3 



increase either by division or by giving off buds, which ra[)i(lly 

 grow into the perfect form. 



The remarkable thing in all these one-celled creatures is 

 that they so much resemble higher animals without any of their 

 organs. The writer of the article Cell iu Chambers's 

 Encyclopaedia says: ''The absence of a circulating fluid, of 

 digestive glands, nerves, sense-organs, lungs, kidneys, an<l the 

 like, does not in any way restrict the vital functions of a 

 unicellular organism. All goes on as usual, only with gi-eater 

 chemical complexity, since all the different processes have but 

 a nnit-mass of protoplasm in which they occur. The physi- 

 ology of independent cells, instead of being very simple, must 

 be very complex, just because structure or differentiation is 

 all but absent." All the one-celled animals and plants go 

 through a series of changes forming the cycle of their life- 

 history. Beginning as a nearly globnlar quiescent cell, they 

 change in form, put forth growths of various kinds, then be- 

 come quiescent again and give rise to new cells by subdivi- 

 sion or budding. 



This fundamental fact, that all organic life-forms begin 

 with a cell and are wholly built up either by outgrowths of 

 that one cell or by its continued division into myriads of 

 modified cells of which all the varied organs of living things 

 are exclusively formed, was first established about the year 

 1840, and was declared by the eminent naturalist Louis 

 Agassiz to be " the greatest discovery in the natural sciences 

 in modern times." The cell is now defined as "" a nucleated 

 unit-mass of living protoplasm." It is not a mere particle 

 of protoplasm, but is an organised structure. We are again 

 compelled to ask, Organised by what? Huxley, as we have 

 seen in Chapter XV., tells us that life is the organising power ; 

 Kerner termed it a vital force ; Haeckel, a cell-soul, but un- 

 conscious, and he postulated a similar soul in each organic 

 molecule, and even in each atom of matter. But none of these 

 verbal suggestions go to the root of the matter; none of thcui 

 suppose more than some ^' force," and force is a cause of 



