The Hunting Wasps 



the large strip of skin to which the sheaths 

 of the wings belong is pushed back by the 

 movements of the abdomen, we see the wings 

 come slowly out of their cases and straight- 

 way, as they become free, assume dimensions 

 out of all proportion to the narrow prison 

 whence they emerge. They are therefore 

 the seat of an abundant rush of vital fluids 

 which swell them and spread them out and 

 which, owing to the inflation which they pro- 

 voke, must be the chief cause of the wings' 

 emergence from their cases. When newly 

 expanded, the wings are heavy, full of juices 

 and of a very pale straw-colour. If the rush 

 of the fluids takes place irregularly, we then 

 see the end of the wing weighed down by a 

 little yellow drop contained between the two 



After stripping herself of the abdominal 

 sheath, which carries the wing-cases with it, 

 the Sphex relapses into immobility for about 

 three days. During this time, the wings 

 assume their normal hue, the tarsi become 

 coloured and the mouth-parts, at first ex- 

 tended, adopt their proper position. After 

 twenty-four days spent in the nymphal stage, 

 the insect has achieved the perfect state. It 

 tears the cocoon that holds it captive, opens 



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