BIOCHEMISTRY OF THE SEXUAL ORGANS 319 



nucleus is no longer able to fuse with the egg nucleus. The eggs 

 then develop into larvae. Other experiments on hybridisation by 

 various authors have shown that under certain conditions develop- 

 ment may be initiated by spermatozoa belonging to a different species 

 without the occurrence of a fusion between the sperm nucleus and 

 the egg nucleus. The resulting larvae are then purely maternal and 

 have half the number of chromosomes. In other words : it is possible 

 to induce parthenogenesis by the spermatozoon. 



