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tions for pupation by selecting a stem, and spinning on it from 

 side to side a number of threads to ensure a good foothold ; next, 

 lying along these threads head downwards, it spins at the bottom 

 of them a broad cone of whitish silk, having a sharpish apex ; then 

 turning round it creeps up the stem a little, and with the anal legs 

 feels about till they find this cone, when they are placed close to- 

 gether on the stem, but touching the base of the cone, and a slight 

 pushing motion is visible by which their circlet of hooks is fixed 

 in the silk spun on the stem : its tail end being thus fixed, the larva 

 stretches out its head and front segments, lifting up at the same 

 time the first and second pairs of ventral feet, and bends itself 

 backwards in a wide sweep from one side of the stem to the other, 

 as though to be assured there is free room for its movements ; it 

 next — while in this semi-detached attitude — and with its thoracic 

 legs rigidly extended, throws back its head, and in this way swells 

 out its breast, like that of a pouter pigeon, leaving a deep hollow 

 between the mouth and the first pair of thoracic legs ; then it 

 bends to one side of the stem and spins a broadish attachment 

 for the first thread of the cincture, and presently with a slow and 

 deliberate motion sweeps round as before to the other side, the 

 head all the while wagging as the silk issues from the spinneret 

 and is guided along the hollow above mentioned ; as the head 

 approaches the other side the body swells out still more as though 

 to stretch the thread, and give it the necessary curvature ; as on 

 commencing the thread, so now on fastening it to the other side, 

 there is a delay for a little, and the fastening seems to be made 

 with a more liquid and glutinous quality of silk than the rest of 

 the thread: the first thread thus completed, the larva proceeds 

 in the same slow and methodical manner — spinning some thirty 

 threads from right to left, and as many from left to right — or sixty 

 altogether for the cincture, the time thus occupied being about 

 one hour and forty-five minutes ; occasionally the first pair of 

 thoracic legs seemed to be called in use to assist at the fastening 

 of the ends of the threads: when enough threads have been spun 

 the larva seems to test their strength by pulling them quite 

 taut with its projecting breast, two or three times, and then ap- 

 parently satisfied, it bends down its head to put it under the 

 cincture, and creeps up inside it till it hangs loosely round its back 

 between the sixth and seventh segments : next it seems to relieve 

 itself by stretching upwards all the front segments that had been 

 so engaged during the spinning, and in a few minutes settles into 

 a quiet posture with head bent down and legs brought close to 

 the stem ; thus it rests, and meanwhile the segments of the body 

 shorten, and their divisions deepen ; the head becomes bent down 

 close to the stem, while the body is held away from it as far as 

 the cincture allows — drawn tight as it is into the deep division 

 between the sixth and seventh segments, so that only the head 

 and tail are in contact with the stem ; at the end of about a day 



