542 



H. H. Ne-, 



ewman 



,^^.i^,- 



lO 



13 



16 



Figs. 9 to 12 (inclusive) are camera drawings, showing a magnification of 20 diameters of the four 

 strains at 56 hours. 



Embryos were killed and fixed in picro-acetic acid, dissected off the yolk, stained in boras carmine, 

 cleared in bergamot oil, and mounted in balsam. 



Fig. 9, average condition in pure bred F. herteroclitus. 



Fig. 10, average condition in hybrid F. heteroditus 9 and F. majalisci'. 



Fig. II, average condition in hybrid, F. heteroditus d^ and F. majalis 9. 



Fig. 12, average condition in pure bred F. majalis. 



Figs. 10 to 16 (inclusive) are camera drawings of embryos prepared as in the series above. The four 

 figures represent the average conditions in four strains of another series at forty-eight hours. The 

 arrangement of figures and magnification is the same as in the series above. 



