ORIGIN OF THE FIRST ORGANISMS 383 



is, therefore, only to be found in organisms which have 

 already reached a comparatively high level on the evolution- 

 ary ladder. Even in the comparatively poorly organised 

 living things of the present time it is far more primitive. 

 It must be supposed that the organisation of the primaeval 

 organisms was even more primitive, although such a form 

 of spatial localisation of the various enzymes and the reactions 

 which they catalyse must have existed even at this stage of 

 evolution. 



Even the reactions of alcoholic fermentation take place 

 far less harmoniously in Buchner's juice, where the spatial 

 localisation of the enzymes is largely destroyed, than in yeasts 

 or bacteria. But, most important of all, in Buchner's juice 

 the process of fermentation follows, as it were, a lone trail. 

 Here none of the energy liberated during the breakdoAvn of 

 sucrose to carbonic acid and alcohol is used rationally in 

 any way. In the living cell, on the other hand, owing to 

 the strict co-ordination of the chemical reactions, this energy 

 participates to a greater or lesser degree in the process of 

 synthesis of living material. 



Of course, it is still very hard to answer the question as 

 to what was the spatial organisation of the earliest living 

 things. Considerable light might be shed on this problem 

 by a comparative study of this organisation among the more 

 primitive contemporary organisms. The study of multiple 

 coacervates might also give some indication of the possible 

 means whereby the simplest internal structure of the original 

 colloid systems could have arisen. In multiple coacervates 

 formed of several components there is an internal separation 

 of the individual components in space, in that small droplets 

 of one coacervate arise within the drops of another. For 

 example, on mixing solutions of gelatin, gum arabic and 

 sodium nucleate, drops are formed, composed of gelatin and 

 gum arabic. Within these drops there are formed small 

 droplets containing gelatin and nucleic acid." This can 

 easily be demonstrated by selective staining or by the use 

 of the ultraviolet microscope. ^^ Various substances and cata- 

 lysts may become localised on the internal surfaces which 

 are formed in this way. 



In summarising what has been said one must emphasise 



