Tronvelot.] 92 [June 24, 



is easily reared and plainly visible, — not concealed beneath the 

 shell of an egg, or in the Avomb of the mother, it is easy to observe, 

 and would, I think, give more certainty to classification. I have 

 compared the young larvje of Papilio Turnus, P. Tro'dus and P. 

 Asterias ; they resemble each other greatly, especially P. Turnus and 

 P. Tro'dus ; P. Asterias does not resemble the others quite so much, 

 and consequently is not so nearly related to either of them. 



It seems to me that by this comparative study of the young larvae 

 or embryos, the original type of a genus, if still existing, could be 

 found with certainty. 



He also spoke of an interesting liabit of the larva of P. 

 Turnus. 



Every one knows that this larva, when at rest, remains upon the 

 middle of the upper part oi a leaf; for this purpose a carpet of silk 

 is spread upon the leaf by the larva. This leaf, by means of the silk, 

 is made to curve a little. On one rainy morning I observed one of 

 these young larvae upon a lilac bush in my gardcji. I certainly 

 thought that the invention of resting in the hollow of a curved leaf 

 on a rainy day was a very poor one, for since the bent leaf performed 

 the office of a gutter, the water must flow through this channel, the 

 larva be inundated and inevitably drowned, if the rain lasted but a 

 few hours. I soon found that there were more braius in the small 

 head than I had supposed. The larva began to move; it spun some 

 silk from one edge of the leaf to the other, and by adding many 

 fibres to make it strong, each new fibre shorter than the preceding, 

 the leaf was soon made to curve more and moi-e. I then began to 

 understand what this laborious work was for, and I thought that 

 sometimes small people might give lessons to larger ones. After 

 about an hour the larva ceased to work, a real bridge was built over 

 the torrent, and upon it laid motionless and out of danger the little 

 larva. Would you call such an act instinct, or would you call it 

 reason? If you call it instinct, I would say that this instinct is very 

 reasonable. 



Mr. Trouvelot further indicated the following points of 

 analogy between Limacodes and some Hymenoptera : — 



1. When the larva of Limacodes is disturbed, it rolls itself like 

 hymenopterous larvae. 



