XI. THE SUMMARY OF PART IV 319 



of the stimulus, a fact showing that it has a primitive feature of 

 irritability. Furthermore, it can grow by incorporating the minute 

 particles of lipoprotein yielded from castor beans, and the growth will 

 be followed by fission if a suitable environmental change is provided. 

 Thus it can accomplish both the growth and multiplication. 



Such cell-like masses can be prepared not only from elementary 

 bodies, but also from the constituents of the elementary bodies into 

 which the latter w^as decomposed. Merck's preparation of ricin which 

 is composed of globulin of a molecular state, combining with lipids, can 

 form elementary-body like particles when its water solution is made 

 weakly acid (pH 5.5) by addition of acetic acid and left in ice box for 

 several days. The particles thus formed can further fuse into proto- 

 plasm-like masses, when stand in the water of pH 5.5 at laboratory 

 temperature. Thus, under a suitable condition, globulin with lipids can 

 form protoplasm-like masses following the formation of elementary-body 

 like particles. 



Since the assimilase, or the protoplasm including viruses, can be 

 regarded as a kind of liquid crystals composed of globulin-like proteins 

 polj'merized with lipids, the fact just mentioned indicates that a liquid 

 crystal closely resembling the protoplasm can be produced in vitro and 

 that it is not entirely unreasonable to regard such a crystal as a very 

 primitive organism. 



The oceans of the primitive age might contain various substances 

 as there were no microorganisms to devour them up, and the sea water 

 might be weakly acid on dissolving carbon dioxide which might be 

 present in rich amount on the surface of the earth. Consequently, 

 when globulin-like protein having the property to sediment readily at 

 a weakly acid reaction were produced in the ocean, they would be preci- 

 pitated accompanied by lipids, and the sediments would form elemen- 

 tary body-like particles which in turn would fuse into protoplasm- 

 like masses. These masses would be endowed wnth assimilase action 

 by their specific structure and thus primeval organisms might appear 

 on this globe. 



Such masses of a liquid crystal would accumulate on the bottom 

 of the primeval ocean, and if a certain structural change capable of 

 producing a structure stronger than the original one occurred in some 

 of the masses, the newly formed structure owing to its stronger charac- 

 ter would spread to surrounding masses. The structure thus could 

 multiply just as viruses can in the protoplasm of host cells. The 



