78 THE CANADIAN ENTOMOLOGIST. 



generations. In Texas there were twenty-five generations be" 

 tween March 31st. and November 3rd. The age at which the 

 females begin to reproduce varies according to the season; early in 

 the season it is from twenty to twenty-seven days, from May to 

 September it is from about six to sixteen days and later in the 

 season from twelve to fifty-three days, the average for the three 

 seasons of the year being early spring twenty-two days, summer 

 nine days, and early fall nineteen days. In Texas the time is 

 shorter, the shortest time being six days. The reproductive period 

 is longer in the average in the spring and fall than in the summer; 

 in the spring the average is eighteen days, in the summer twenty- 

 six days and in the fall, forty-five days. The longest likewise is 

 greater in the spring and fall than in the summer, the average is 

 thirty-five days and the longest is seventy-eight days. The 

 rapidity of production it very great: in Indiana the greatest 

 number of young produced by one female in twenty-four hours 

 was eight, in Texas ten. The greatest number of young produced 

 by one individual was ninety-three. The average number of 

 young for the entire viviparous breeding season, over a period of 

 three years (1907-9), was 28.2; the average number of young pro- 

 duced in a day is greatest in the Spring. 



The sexual forms, male and female, appear in Indiana at the 

 end of September and adults may be found from October until the 

 cold kills them off in December.* The oviparous females become 

 adult in 11 to 41 days according to weather conditions, and if 

 males are present they oviposit in from three to nine days. 

 The males live from 8 to 10 days after reaching maturity, the 

 females from 31 to 68 days if males are present; if males are not 

 present they can live 88 days after reaching maturity. Aberrant 

 individuals were found containing both living embryos and true 

 eggs. 



Throughout the Northern United States and no doubt in 



* On page 77 the author states "one agamic female may reproduce all 

 agamic individuals, a combination of agamic males and oviparous females or 

 only true females and males." What are "agamic males"? An agamic female 

 we know is a female which produces young in a parthenogenetic manner, that is, 

 without fertilisation by the male. Huxley was the first, I bL'leive, to use the 

 term "agamic" for this form of reproduction in the Aphids. As the male aphid, 

 fortunately, cannot give birth to young either sexually or asexually is it not 

 misusing the word to apply it to the male? 



