PARTHENOGENETIC TENDENCY IN MELANOOERA MENIPPE. 275 



thera the yolk was found to be very fluid, blackish, and 

 decomposed; thus the condition of the yolk was in marked 

 contrast with that of normally laid unfertilised eggs. 



The eggs obtained from six unpaired female menippe, 

 after they had been laid for seven weeks, were cut open with 

 scissors and examined with a strong hand-lens. In a small 

 percentage of the eggs distinct traces of development could 

 be detected. The condition of the egg as seen by a lens may 

 be indicated by numbered stages. 



Stage 1, when there is no obvious development. 

 Stage 2, when there is some sign of a blastoderm. 

 Stage 3, when there is an obvious embryo and a few hairs 

 may be visible. 



Stage 4, when the development of the embryo is consider- 

 ably advanced and many hairs are visible. 

 Stage 5, when the embryo actually hatches. 

 Ordinary fertilised eggs of menippe hatch in about 

 three weeks after being laid. In the case of the pairing of 

 menippe ? x menippe (S, which occurred on October 

 22nd, the eggs hatched on November 16th. 



With regard to the eggs laid by unpaired female menippe 

 it was quite clear that the maximum development possible had 

 occurred at the time of examination, since considerable desic- 

 cation had taken place, and a few of the eggs were quite dry. 

 In the accompanying table the details with respect to the 

 eggs of the unpaired menippe are given. 



