INFLUENCE IN RADIO-ACTIVITY 349 



forming a layer of organic debris, which would possess inhibitory 

 powers of its own over the natural radio-activity. By the increase 

 in the thickness of this layer, which naturally would be variable, 

 the inhibitory effects were more appreciable, and it became possible 

 for living organisms to exist at gradually increasing depths. 



The organisms, whose original habitat was the surface of the 

 greatest depths, naturally spread downwards and laterally, and 

 those living organisms which reached the deeper parts of the 

 ocean or the shallower waters, where the layer was still thin, were 

 killed : where the layer was thicker, were irritated and formed 

 pathological monsters, which lived for some time and died without 

 reproducing their kind ; but where the layer was still thicker, the 

 irritation was very slight and caused slight modifications and 

 increase of growth without mhibiting the power of reproduction. 

 Certain of these modifications and mcrease of growth would be 

 transmitted to their descendants, and though almost imperceptible 

 probably at first, in the course of centuries the same process on 

 innumerable successive generations would make the modification 

 a permanent characteristic and give rise to a new type. This was 

 the creation of a new genus or species. 



During this period of time some of the accumulations of dead 

 organic matter in the depths of the ocean were being moved by the 

 action of the waters and prime\'al storms nearer and nearer to the 

 edges of the barren lands, until finally the fringe of this land was 

 actually covered by a deposit of this dead organic debris. This 

 process was assisted also by organisms dying and falling to the 

 bottom, as the area at the surface in which life was capable of 

 support was increased by the shifting of the deposit further and 

 further towards the land, and so reducing the effects of the earth's 

 natural radio-activity. All this would be a process of numberless 

 centuries, and at the same time also the earth's radio-activity was 

 being very gradually diminished. 



It is a general truth that the eftects of irradiation are mani- 

 fested only where the rays are absorbed, and whilst the organisms 

 were of minute size, those rays which were absorbed would be felt 

 by the more vital central cellular elements ; but as the organism 

 increased in size certain rays, depending on their co-efficient of 

 absorption, would be absorbed in the superficies, and this would be 

 irritated ; and those organisms which acquired a proliferation of 

 these cells through the irritation would be more capable of pro- 

 tecting their more vital central elements, and hence have the 

 greater chance of survival ; thus in succeeding generations those 

 with the thinner superficies would be killed off, making the thicker 

 covered organisms more common, until ultimately there was 

 created a type with a primitive epidermis or integument. This 

 was probably the first great influence of radio-activity. 



Later, owing to other factors of evolution, or assisted possibly 

 by anaphoretic action of /i activity and cataphoretic action of « 

 activity, certain organisms acquired a false covering, e.g., the shell 

 of the primitive shelled organisms. Such coverings gave the 



