GREAT STEPS IN ORGANIC EVOLUTION 845 



ordinary Protozoa (unicellular animals) and ordinary Protophytes 

 (unicellular plants), for most of these (like Amoebae, Slipper Animal- 

 cules, Pleurococcus from the tree-stem, and yeast-plants) are 

 already, in spite of their relative simplicity, too highly specialised. 

 They are not at all within hailing distance of the first organisms ; a 

 Protozoon like Paramoecium is extraordinarily intricate and to call 

 it "a simple cell" is almost fallacious. It is a very complex organism, 

 within the non-multicellular phase of being. If we look for light as 

 to primitive organisms from creatures of to-day, we must look to 

 very much simpler organisms than Slipper Animalcules or Amoebae. 

 It is possible that the often minute Chlamydozoa, which are near the 

 border-line of microscopic visibility, may give us hints — when we 

 know more about them — in regard to the original organisms. 





^^^BR 



■^¥% 



Fig. 145. 



An Infusorian, Mastigamceba, which is at once amoeboid with pseudopodia 

 (PS) and flagellate with a lash (FL). N, the nucleus; V, a vacuole; BR, 

 basal processes. 



If there is any general view as to the first organisms, it is that 

 they were perhaps like much simplified Amoebae, little unities of 

 colloidal proteins, and these beginning to come together into larger 

 masses; incipiently correlated, that is; and (somehow) able to utilise 

 the radiant energy of sunshine so as to build up more proteins, or 

 antecedent stages of proteins, from environing material; able to 

 keep agoing, to balance accounts; viable, that is. Many a zoologist 

 still, surely too simply, pictures a first organism as like a simplified 

 Amoeba — an Amoeba reduced to essentials. So, too, the botanist 

 pictures a first organism as like a simplified Pleurococcus, or Yeast- 

 plant, or Bacterium. Perhaps the simplest current view is that of 

 a colloidal protein-integrate, without structural definiteness, much 

 less complexity; yet a protoplasmic firm, a unity able to divide, a 

 creature able to go on, to pay its way, to balance accounts, and of 



