554 TPIE ENTOMOLOGIST. 



experiineuted on died, we find her discoursing in the follow- 

 ing unqualified manner in ' Ilearlh and Home' for January 

 13th, 1872, in treating of Papilio asterias: — "When the 

 worms become of the right size cut off their supply of food, 

 and every one will produce a male butterfly ! On the other 

 hand, even after they have left their food-plant and selected 

 their place to change to the chrysalis, disturb them, make 

 them leave their place, and coax them with a fresh supply of 

 their favourite food, and continue to feed them for about two 

 weeks longer, and all will be females!" 



Led by Mrs. Treat's observations to test the question, I 

 last summer conducted a few experiments, which resulted 

 very differently from those recorded in the article referred to, 

 and which, after briefly reviewing the article, I will detail. In 

 waiting for some of these results I have been obliged to defer 

 writing this article till the present lime. In the first experi- 

 ment with Papilio asterias, mentioned by Mrs. Treat, some of 

 the larvae died, and we are not told whether the number 

 experimented with was large or small. In the experiment 

 with the same insect in 187*2 we are told that of seventy-nine 

 specimens that had been labelled males (a few chrysalides 

 having died) three females only were produced. On the 

 other hand, those that were well " fed up," and labelled 

 females, produced sixty-eight females and four males. The 

 original number so laljelled is not given, and it is not stated 

 whether any chrysalides failed to produce the imagines ; so 

 that we are left to infer that seventy-two were experi- 

 mented with, and that they all produced the butterfly, — a 

 success in rearing which is remarkable. In the third experi- 

 ment with twenty larvai, nine females and eight males were 

 produced, the other three failing. In the experiment with 

 Vanessa Antiopa more than half the larva) died, and in the 

 trials with Anisota rubicunda some also died and were 

 parasitized. 



Now Papilio* deposits its eggs singly, and from experience 

 in breeding Asterias, Troilus, Turnus, and Ajax, from the 

 egg, I am satisfied that it would be very difScult to get any 

 great number to hatch on the same day, or to become 

 chrysalides or imagines on the same day. The eggs must 

 have been gathered singly, or the larva? of different ages 

 * I use the terra in the old, and uot in Mr. Scudder's, sense. 



