iv] DIPLOPTERA 49 



the stores of fat accumulated within the body of the 



/ 



well-fed grub. Gradually the form and colour of the 

 perfect wasp (imago) become visible through the 

 delicate skin of the pupa which at length bursting 

 open sets free from its shroud the fully-formed young 

 worker-wasp. 



The young imago bites through the floor of her 

 cocoon with her mandibles and crawls out upon the 

 under surface of the comb. The whole development 

 from egg to imago occupies about a month or six 

 weeks. At first the body of the young wasp is moist, 

 and its colour dull ; the wings too are not fully 

 expanded nor firm : their final consistency, form and 

 colouring are attained while the freshly emerged 

 insect hangs, back downwards, from the comb. The 

 excreta that have accumulated during the period of 

 pupal quiescence are ejected at this stage. The 

 front wings of the young wasp are not, at first, 

 folded longitudinally : it is not until they have been 

 extended that the ledge along their hinder margin 

 becomes engaged on the hooks which lie along part 

 of the front border of the hind wing: then, on the 

 wings being brought into the position of repose, the 

 attachment between the two wings is maintained 

 and the hind part of the forewing folds mechanically 

 under the front portion. One of the first acts of the 

 wasp in full control of her limbs is to clean herself 

 with the brushes and bristles with which her legs are 



L. B. W. 4 



