Wasps 



holding it in place. In others the comb is enclosed in a spherical 

 envelope of paper with a small opening at the bottom. In the 

 more complicated nests there is a series of combs placed one be- 

 low the other, and the whole is enclosed in a case made of many 

 thicknesses of paper. The nests are enlarged by adding cells to 

 the edges of the combs, and room is made for these new cells by 

 removing the inner layers of the envelope; the portion removed, 

 however, not being wasted, but chewed up again by the wasps 

 and added to the outside. The nests are suspended from 

 branches of shrubs and trees or from fences and roofs. Some of 

 the smaller species build their nests in the ground and under 

 stumps. In each cell of the comb an egg is laid. Owing to 

 the position of the comb, when the larva hatches it is suspended 

 head downwards in each cell and holds its place while young by 

 means of a glue and when old by its enlarged head end, which 

 completely fills the open part of the cell. They are constantly 

 nursed by the females and workers, and are fed with a brownish 

 fluid which is prepared by the workers or females and consists 

 of the juices of fruits and the remains of other insects which have 

 been chewed up. When it gets full grown the larva spins a 

 silken cocoon, the lower end of which serves as a cap to the 

 cell, and then it transforms to a pupa. After the adult wasp is- 

 sues the cell is cleaned out by the workers, and is used again by 

 the queen, and, as the whole period from the laying of the egg 

 to the emerging of the full-grown wasp is about a month in the 

 northern states, a comb made early in the season serves for 

 several successive generations. 



As a rule the males and queens are not developed until 

 toward autumn. At this time larger cells are made for the re- 

 ception of the eggs which are to produce these forms. Thus if a 

 large wasp nest be examined it will be seen that the top combs 

 contain smaller cells and all of the same size, while the lower 

 combs contain larger cells. This habit which the social wasps 

 have of beginning at the top and building downward was what 

 suggested to Gulliver's Laputan philosopher that they should be- 

 gin by building the garrets of every house first of all and then 

 gradually working down to the lower stories and the cellars. 



The most notable of the social wasps in the United States is 

 the bald-faced hornet (Wespa maculata) above referred to. It 

 builds the enormous paper nests commonly seen attached to the 



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