﻿IIO HYMENOPTERA 



addition to the rough silk that serves as a sort of scaffolding on 

 the exterior : the internal coat is polished and is of a dark colour, 

 owing to its being coloured with a matter from the alimentary 

 canal : the other layers of the cocoon are white or pale yellow. 

 Fabre considers that the outer layers of the cocoon are formed 

 by matter from the silk-glands, while the interior dark coat is 

 furnished by the alimentary canal and applied by the mouth of 

 the larva : the object of this varnish is believed to be the exclu- 

 sion of moisture from the interior of the cocoon, the subterranean 

 tunnels being insufficient for keeping their contents dry through- 

 out the long months of winter. During the whole of the pro- 

 cess of devouring the four crickets, nothing is ejected from the 

 alimentary canal of the larva, but after the cocoon is formed 

 the larva ejects in it, once for all, the surplus contents of the 

 intestine. Nine months are passed by the Insect in the cocoon, 

 the pupal state being assumed only towards the close of this 

 period. The pupa is at first cpuite colourless, but gradually 

 assumes the black and red colour characteristic of the perfect 

 wasp. Fabre exposed some specimens of the pupa to the light 

 in glass tubes, and found that they went through the pupal meta- 

 morphosis in just the same manner as the pupae that remained in 

 the darkness natural to them during this stage of their existence. 

 Sphex coeruleus is frequently stated to have the habit of pro- 

 visioning its nests with both Orthoptera and Spiders ; but Kohl 

 considers with reason that this record is, as regards spiders, a 

 mistake, arising probably from a confusion with some other 

 Insect of' similar appearance, such as Pel opticus (Sceliphro?i) 

 coeruleus. S. coeruleus is no doubt the same as S. (Chlorio/i) 

 lobatus, which Eothney observed in East India, provisioning its 

 nests with Orthoptera. He discovered a nest in process of con- 

 struction, and during the absence of the mother-wasp abstracted 

 from the burrow a large field-cricket that she had placed in it ; 

 he then deposited the Orthopteron near the cell ; the parent 

 Sphex on returning to work entered the tunnel and found the 

 provision placed therein had disappeared ; she came out in a state 

 of excitement, looked for the missing cricket, soon discovered it, 

 submitted it to the process of malaxation or kneading, and again 

 placed it in the nest, after having cleared it from some ants 

 that had commenced to infest it. She then disappeared, and 

 Eothney repeated the experiment ; in due course the same series 



