ARTIFICIAL PARTHENOGENESIS IN THE SILKWORM. 1 9 



June 1 1, one gray egg. 

 June 21, one gray egg. 

 August 28, twenty-five grayish-pink and five gray eggs, but 



mostly dead. 

 March 5 (1907). All eggs are dead. 

 Lot 4 : Treatment, two minutes. Acid in concentrated solu- 

 tion. Lot of sixty eggs. Treated June 20 (1906). 

 June 27, three eggs, partly gray. 

 August 28, eight gray ; these and most of the yellow eggs 



still alive. 

 March 5 (1907), all dead. 

 Lot 5 : Treatment, two minutes. Acid in concentrated solu- 

 tion. Lot of 250 eggs. Treated June 20 (1906). 

 June 27, five or six gray or cherry eggs. 

 August 28, fifteen cherry eggs ; two gray, a few of which 



are alive. 

 March 5 (1907), all dead. 

 Lot 6 : Treatment, one minute. Acid in concentrated solu- 

 tion. Lot of 205 eggs. Treated June 25 (1906). 

 June 27, one grayish egg. 

 August 28, three gray, eleven cherry eggs. Almost all 



alive. 

 March 5 (1907), all dead. 

 Lot 7 : Treatment, one minute. Acid in solution. Lot of 

 140 eggs. Treated June 25, (1906). 

 June 27, two gray eggs. 

 July 1, fourteen gray eggs, mostly alive. Most of the 



yellow eggs also alive. 

 March 5 (1907), all dead. 

 Lot 8 : Treatment, one half minute. Acid in solution. Lot 

 of fifty eggs. Treated June 27 (1906). 

 July 1, two cherry eggs. 



August 28, five gray eggs; several cherry, mostly alive. 

 About two thirds of the yellow eggs also alive. 

 Lot 9 : Treatment, one half minute. Acid in solution. Lot of 

 ninety eggs. Treated June 27 (1906). 

 July 1, eight cherry or grayish eggs. 

 August 28, twenty-seven gray or pink-gray eggs of which 



