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EIGHTH ANNUAL REPORT 



easily watched. The other molts are very similar, except that the 

 wing-pads increase but moderately in size with each. When about to 

 acquire wings the pupa crawls up some post, weed, grass-stalk or 

 other object, and clutches such object securely by the hind feet 

 which are drawn up under the body. In doing so the favorite posi- 

 tion is with the head downward, though this is by no means essential. 

 Remaining motionless in this position for several hours, with anteunse 

 drawn down over the face, and the whole aspect betokening helpless- 

 ness, the thorax, especially between the wing pads, is noticed to swell. 

 Presently the skin along this swollen portion splits right along the 



[Fig. 39.] 



KocKYlMouNTATN LoCDST :— Process of acquiring Avijigs ; a, piipawitli skiu just split 

 on the back ; 6, tlie imago extruding; c, do. nearly out; d, do. with M'iugs expanded; c, 

 do. with all parts perfect. 



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 split- 

 ting, and when it presents the appearance of Fig. 39, a. As soon as 

 the skin is split, the soft and white fore-body and head swell and grad- 

 ually extrude more and more by a series of muscular contortions; the 

 new head slowly emerges from the old skin which, with its empty 

 eyes, is worked back beneath ; the new 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 my Fig. 39, h, the four front pupa-legs being 

 generally detached and the insect hanging 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 ar- 

 duous labor — of swelling and contracting— with an occasional brief 

 respite, the antenna^ and the four front legs are freed, and the fulled 

 and crimped wings extricated. The soft front legs rapidly stiffen and, 

 holding to its support as well as may be with these, the nascent locust 



