370 Mr. H. Ling Roth's observations on Carausius. 



it commences to eat up the old skin close to which it has 

 attached itself. This meal is an almost invariable proceed- 

 ing, unless through some accident the slough has fallen 

 to the ground or the nymph has been disturbed in some 

 way. The skin shrivels considerably, so that the head 

 portion is not very low down, and it is here that the nymph 

 begins its repast, not biting pieces off, but drawing in the 

 skin by means of the palpi. When it has devoured the 

 skin of all but one hind-leg it looks for this, generally 

 detached in the course of the feed, eats it up also, and then 

 searches the twig for more. If the skin has fallen the 

 nymph or insect will look for it where it should be, and 

 occasionally hours afterwards it may devour it when it 

 finds it. If otherwise disturbed at this meal it may eat 

 part only or none at all. The proportion of uneaten sloughs 

 is greater when there are a large number of nymphs or in- 

 sects in a jar than when a nymph has a jar to itself, for 

 they disturb one another very considerably. I once saw 

 a nymph start to eat up a newly discarded skin before its 

 proper owner was ready to begin on itT Occasionally, 

 too, in the course of the shedding the nymph is disturbed 

 by another crawling over it, whereupon it gives its body 

 a jerk which does not always get rid of the troubler. Pre- 

 paratory to the change the nymph is not very particular 

 as to what it attaches itself to, and will even adhere to 

 another nymph, and as this species has a common habit of 

 hanging five or six close together in the day-time, like a 

 bunch of asparagus, the quiet progress of the moult does 

 not in any way cause a disturbance, and proceeds as in 

 the ordinary course.* 



On one occasion I observed a clot of green liquid develop 

 at the proto-mesonotum joint similar to that mentioned 

 on p. 357. It was about 1'5 mm. in diameter, did not 

 seem to inconvenience the nymph at all, and gradually 

 disappeared, apparently by absorption. This clot ap- 

 peared after the discarded skin had passed clear of the head. 



After the ecdysis the body is much attenuated and 

 generally lighter and brighter in colour; in the course of 

 3 to 4 days it has filled out again, and if the full number 

 of moults has not been passed the swelling slowly recom- 

 mences until the next ecdysis occurs. 



* With the Walking-Stick, Diapheromera femorata, Say, H. H. P. 

 and H. C. Severin observed a peristaltic-like movement in the 

 course of the moult (loc. cit., 1911, p. 313). 



