M. Hubert on an Emigration of Butterflies. 345 



naturalists, divided, that they might better observe the phe- 

 nomena. 



Those who were younger and more active followed the but- 

 terflies for a long time in the direction to which they were go- 

 ing, the others went to the other side from whence the columns 

 were coming; but although they accompanied them a very 

 long time, they did not succeed in beholding either the begin- 

 ning or the end of this inoffensive army. 



The passagje lasted upwards of two hours, without any in- 

 terruption, from the moment when they were first observed, 

 and it is probable that they had begun some time before they 

 caught the eye of Mrs de Meuron. 



The column was from ten to fifteen feet broad ; these but- 

 terflies did not alight upon the flowers; their flight was low, 

 rapid, and equal. 



Such are the facts which have been unanimously transmit- 

 ted to me by the members of the enlightened and interesting 

 family who were witnesses of the curious phenomenon. 



All that has been capable of observation in this remarkable 

 fact has been examined as if by real naturalists, and with that 

 sort of interest which overlooks no characteristic circumstances 

 in a new question, by those young persons, occupied with col- 

 lections, and well versed in the natural history of insects. 



The fact then is undoubted. 



But it appears to me most "singular, that it relates to a spe- 

 cies of butterfly, whose caterpillars do not live in societies (at 

 least not in our country) and are themselves isolated from the 

 time they quit the egg. 



I shoidd have been less surprised if I had heard of the 

 emigrations of the butterflies Petite-tortue, Paon de jour, or 

 Morio, whose caterpillars live in common and in very nume- 

 rous families upon the nettle and the willow. All the cater- 

 pillars who live in societies seem to keep together by the com- 

 mon ties of utility ; each one goes out to explore, and leaves 

 behind them the silk which helps to conduct their companions 

 upon the branch where they have found food ; but when once 

 they arcj provided with wings these insects seem no longer to 

 recognize each other, as if the state of the chrysalis, that sleep 

 of the instinct, during which the developemeikt of the organs 



VOL. VII. NO. II. OCT. \ST(. z 



