128 THE ORIGIN OF LIFE 



that this self-movement in microscopic bodies is 

 merely the result of slight variations in the surface- 

 tension due to the secretions from these bodies and 

 an effect not connected with vitality but capable of 

 taking place without it : as in fact we know it can 

 take place by the solution of small particles of cam- 

 phor in water. 



The vitality of the newly formed eggs in Loeb's 

 experiments was, as it seems, unquestioned, and the 

 accuracy of the observations likewise demonstrated 

 by the use of controls. Needless to say, the observer 

 himself is a sufficient guarantee of this. 



Under the action of the salt solution the albumin- 

 oids coagulate, probably by the action of free ions, 

 and this wall or membrane being semi-permeable 

 allows the diffusion of water into the cell. By 

 pressure, or some other means, the nucleus sub- 

 divides, and also in due course forces the division 

 of the cell with it. It thus looks as if the action of 

 the sperm isprimarily that of some secretion it emits, 

 which, by its power of coagulating a layer on the 

 surface of the egg, thus indirectly brings about its 

 subdivision. 



The artificially subdivided cells are, as we say, 

 lacking in the vigour of the naturally fertilised ones, 

 thus showing that the sperm has not taken the full 

 part in the process. 



Apart, however, from any such considerations it 

 does not seem probable on the face of it that 

 artificial parthenogenesis, possible though it is, can 

 be of any real importance in propagating the 



