Plate II 



Pictor:al table, illustrating three stages of the Type Series (Series I). 



The top row, H y in this plate and in the two succeeding plates, depicts stages in the development 

 of pure F. heteroclitus. 



The second row, //, represents simultaneous conditions in the hybrid strain F. majalis C? and 

 F. heteroclitus ? . 



The third row, m. simultaneous conditions in the reciprocal cross F. heteroclitus o' and F. majalis 9 . 



The bottom row, A/, simultaneous conditions in pure F. majalis. 



All figures are camera drawings except that the egg membrane has been drawn in w.th the compass. 

 All figures show a magnification of 12 diameters. 



