FACTS 217 



plete cytoplasm, male or female. Consequently, in order 

 that the male or female maturation can be produced in the 

 nucleus or the cytoplasm, it is necessary that the nucleus 

 as well as the cytoplasm of a complete cell should contain the 

 two sexes. Then maturation is explained by the disappear- 

 ance in cytoplasm and nucleus of all elements of the sex 

 opposed to that of the mature element finally obtained. 



This being the case, without making any hypothesis as 

 to the nature of the elements of opposite sex existing in 

 either nuclear or cytoplasmic protoplasm, and without 

 asking if these elements are chemical or colloid, we can 

 represent the plan of a complete cell as an agglomeration 

 of bipolar elements (Fig. 18, A). Male maturation should 



A B 



FIG. 18. DIAGRAM or SEXUAL MATURATION. 



be due to the disappearance of all the female half -elements 

 and female maturation to the disappearance of all the male 

 half-elements (Fig. 18, B). 



What is the cause of maturation, male or female ? We 

 shall know only when we have discovered the nature itself 

 of the differences which exist, in each bipolar element of 

 protoplasm, between the male pole and the female pole. 



The Artificial Parthenogenesis of J. Loeb 

 Meanwhile, without having discovered as much as this, 

 J. Loeb has found an experimental means of suspending the 



