200 



NATURAL HISTORY OF ARTHROPODS. 



Fig. 277. — Pupa 



IG. 278. — The 

 imago protrilil- 

 ing. 



under the oody. In doing so the favorite position is with the liead downward, though 

 this is by no means essential. Remaining motionless in this position for several hours, 

 with antennte drawn down over the face, and the whole aspect betoken- 

 ing helplessness, the thorax, especially between the wind-pads, is noticed 

 to swell. Presently tlie skin along this swollen portion sjilits right 

 along the middle of the head and thorax, starting by a transverse, 

 curved suture between the eyes, and ending at the base of the abdomen. 

 "Let us now imagine that we are watching one from the moment 

 of this splitting. As soon as the skin is split, the soft and white fore- 

 body and head swell, and gradually extrude more and more by a series 

 of muscular contortions; the new head slowly emerges from the old 

 with skin just gkin, which with its empty eyes, is worked back beneath, and the jiew 

 feelers and legs are being drawn from their casings and 

 the future wings from their sheaths. At the end of six or seven minutes 

 our locust — no longer pupa, and not yet imago — looks as in Fig. 278, 

 the four front puparlegs being generally detached, and the insect hang- 

 ing by the hooks of the hind-feet, which were anchored, while yet it had 

 that command over them which it has now lost. The receding skin is 

 transparent and loosened, especially from the extremities. In six or 

 seven minutes more of arduous labor — of swelling and contracting — 

 with an occasional brief respite, the antennaj and the four front legs are 

 freed, and the fulled and crimped wings extricated. The soft front-legs 

 rapidly stiffen, and, holding to its supjjort as well as may be with these, 

 the nascent locust employs whatever muscular force it is capable of to 



draw out the end of the abdomen and its long hind-legs. This in 

 a few more minutes it finally does and with gait as unsteady as that 

 of a new-dropped colt, it turns round and clambers u]^ the side of 

 the shrunken, cast-off skin, and there rests while the -v^ings expand 

 and every part of the body hardens and gains strength — the 

 crooked limbs straightening and the wings unfolding and expand- 

 ing like the petals of some jiale flower. The front-^^■ings are at 

 first rolled longitudinally to a point, and as they expand and un- 

 roll, the hind-wings, which are tucked and gathered along the 

 A'eins, at first curl o\-er them. In ten or fifteen minutes from the 

 time of extrication these wings are fully expanded and hang down 

 like dampened rags. From this ])oint on, the broad hind-wings 

 begin to fold up like fans beneath the nari-ower ivont ones, and 

 in another ten minutes they have assumed the normal 

 attitude of rest. Meanwhile the pale colors which 

 always belong to the insect while moulting have been 

 gradually giving way to the natural tints, and at this 

 stage our new-fledged locust presents an aspect fresh 

 and bright. If we now examine the cast-off skin, we 

 shall find every part entire with the exception of the 

 rupture which originally took place on the back ; and 

 it would puzzle one who had not witnessed the opera- 

 tion to divine how the now stiff hind shanks of the mature insect had been extricated 

 from the bent skeleton left behind. They were in fact drawn over the bent knee- 



Fia. 279. — The imago 

 nearly out. 



Fig. 280. — Imago with wings expanded 

 but not folded. 



