108 CONCLUDING REMARKS. 



From these fragmentary statements it will be seen what a 

 wide field still stands open for the investigation of Partheno- 

 genesis, accompanied as it is by such extremely peculiar pheno- 

 mena ; in no case, however, will this portion of the history of 

 the reproduction of animals, enveloped as it is in so much ob- 

 scurity, allow itself to be quickly and easily cleared up ; for, as 

 regards Psyche Helix, for example, the entomologist desirous of 

 knowledge, and seeking after the males of this moth, must arm 

 himself with patience in order to arrive at the goal ; for if, in 

 this case, which is probable, Parthenogenesis has its hand in the 

 affair through several generations, as only a single generation of 

 this moth, the male of which has been sought in vain for the 

 last seven years, is produced annually, we should still have to 

 wait some years before a male generation at last makes its ap- 

 pearance, and reveals the mystery interwoven with this moth. 



