378 THEOPHILUS S. PAINTER 



to imagine that any process which would remove part of the 

 protoplasm or otherwise disturb the relations^ would upset the 

 reaction. Or, if we think of some specific substance, a true 

 germ path determiner, as being present in the germinal cells, 

 the loss of part or all of this substance would produce diminu- 

 tion in such cells. Which of these two views will prove the 

 correct one, it is impossible at the present time to say, but the 

 e^ddence to be presented can be equally w^ell interpreted for either 

 case. 



In the eggs treated with COo the quantitative relations are fre- 

 quently upset by the formation of protoplasmic balls. These 

 balls are apparently formed b}^ the giving away of the cell wall 

 when the cleavage pressure is at its height. It is invariably 

 found when the A and B blastomeres fail to separate. More 

 rarely, it may be given off from the dividing primordial germ cell. 

 In figure P we have such a case, associated with the diminution 

 process in the germinal cells. Most of the eggs which have 

 shown diminution in the germinal cells, have been characterized 

 by the presence of such a ball. In glancing over the figures given 

 by Kautsch, I notice also the frequent appearance of such a 

 ball, although Kautsch does not mention them in his description 

 of these abnormal eggs. Finally, in the eggs shown in figures 

 16 and 17, we see a large mass of protoplasm has been cut off 

 from the germinal cell. The constant occurrence of the proto- 

 plasmic ball with the diminution going on in the primordial 

 germ cell has convinced me that the two have a close relation. 

 Here we seem to have an explanation for the diminution 

 process, for, when this mass of protoplasm is thrown out of the 

 germinal cell, substances (such as the germ path determiner itself 

 or some material necessary for its action) are either removed, 

 or the balance between the inter-reacting chemical substances 

 is upset. Either of these causes would probably be sufficient 

 to bring about the diminution. In the case of the ectodermal 

 cells, A and B, the formation of the protoplasmic ball has no effect 

 on diminution since the substance inhibiting this process is not 

 present. 



