156 The Mechanistic Conception of Life 



oxygen can be shown in various ways. The maturation of the 

 egg itself depends upon oxidations. If the oxygen is withheld 

 from the immature eggs, or if the oxidations ia the immature 

 eggs are inhibited by potassium cyanide, the process of matura- 

 tion does not take place. Maturation is, therefore, also a 

 function of oxidations. The eggs of a female, which were 

 unripe, were divided into two groups : the one group remained 

 in sea- water in contact with oxygen; the other was put into 

 sea-water whose oxygen -had been removed by a current of 

 hydrogen. The eggs of the second group remained alive; the 

 eggs of the first group perished ia a few hours. 



It is not even necessary to drive out the air by hydrogen; 

 the life of the unfertilized eggs can also be preserved by putting 

 large masses of them into a narrow glass tube which is sealed 

 at the bottom. The eggs sink to the bottom of the tube, and 

 those which are lying near the bottom receive no oxygen, since 

 the oxygen which diffuses from the air through the sea-water 

 is consumed by the uppermost layer of the eggs. On account 

 of this lack of oxygen the eggs at the bottom of the tube do not 

 mature and do not perish; hence by withholding oxygen from 

 the immature eggs their maturation and death are prevented. 



If the oxygen is withheld from the eggs immediately after 

 they become mature their life is also saved. A. P. Mathews 

 has repeated this experiment and obtained the same results. 

 This proves that the death of the mature but imfertilized egg is 

 determined by oxidations. If these oxidations are inhibited 

 death does not occur. When these experiments were first 

 published they caused opposition. This opposition was based 

 on the fact that potassium cyanide was used in part of the 

 experiments. The objection was raised that the potassium 

 cyanide in these experiments acted only by preventing the 

 development of bacteria. The authors, however, who raised 

 this objection, overlooked the fact that lack of oxygen acts in 

 exactly the same way as the addition of potassium cyanide. 



