MATURATION OF MALE EGGS IN APHIS. 75 



observations on male eggs of Phylloxera, it seems desirable to 

 bring the results obtained from this autumn's collections of the 

 Oenothera aphid, to the notice of those interested in the subject. 

 In a recent paper, entitled " Mendelian Inheritance of Sex," 

 Hagedoorn has quoted me as authority for a statement that male 

 aphid eggs give off two polar bodies. I have found only one 

 polar body in male and other parthenogenetic eggs, and have 

 so stated the fact with all the evidence at hand ('05, PI. II., Figs. 

 17 and 18, and text p. 317). Fig. 5 shows one of many early 

 segmentation stages of male eggs found in aceto-carmine prepara- 

 tions, showing only one polar body 

 Biological Laboratory, 

 Bryn Mawr College, 

 November 25, 1909 



