254 Notes on the Habits of some Lejjidopterous Larvce. 



leader, and why. they follow Mm so obediently; and by what 

 means one individnal obtains authority over his fellows. The 

 line marches along nntil a suitable tree is reached, then the 

 larva? dispersing among the branches, commence their work of 

 destruction. It is probable that they return in the same order 

 in which they set out, but I have never had the good fortune 

 to see them re-enter their nests. When they are on the march, 

 if you knock the leader away, the whole line halts and remains 

 stationary until the chief has resumed his place. If you kill 

 the leader, the line at first remains quiet, then after a little 

 time falls into confusion, various individuals going hither and 

 thither, apparently bewildered, possibly searching for their 

 leader. Presently they reform line under a new chief, whose 

 direction they obey as they obeyed his predecessors, and con- 

 tinue their march. If you knock some individuals out of the 

 line, their fellows will halt and wait until they have resumed 

 their places, but if you kill or disable any, the remainder, after 

 waiting for some little time, will close up their diminished rank 

 and proceed on their way. They march straight on, heedless 

 of danger, and well they may, for you had better not touch 

 them without gloves. The hairs with which they are covered 

 are so poisonous that it is said death has followed upon handling 

 these larvse ; this, however, I should think due to a very 

 diseased state of the blood. Birds, those enemies of the insect 

 tribe, do not seem to prey upon these larvse, which appear thus 

 to increase unmolested. The ravages which they commit 

 among the firs and pines near Hyeres and Cannes are very 

 great; I have often counted 100 nests in the course of a single 

 ramble. I am at a loss to account for the very poisonous 

 nature of these creatures ; I have subjected their hairs to 

 careful microscopic investigation ; they are certainly formidable 

 looking weapons, jagged and barbed on each side ; but this is 

 the case with the hairs of other species, which are harmless 

 (e.g., our common Bombyx puclilmnda) . There is a long bulb 

 at the root of each hair, which I have conjectured to be a 

 poison-bag, similar to that found in venomous serpents. This 

 is merely a conjecture, however, as the bulb in question ma;/ 

 be only the usual root of the hair, but I give it here as being 

 the only way of accounting for the poisonous nature of these 

 hairs which has occurred to me. 



When about to assume the pupa state, about the month of 

 April, these larvte quit their nest in the usual order, and often 

 traverse very considerable distances before finding a place 

 suited to their purpose. They bury themselves, and form a 

 rough cocoon of earth, hair, etc., at a depth of an inch or two 

 below the surface. Hence the choice of a proper locality is a 

 matter of importance, as the larva? cannot form their cocoons 



