Wasps 



building operations, and they thus used this paper already pre- 

 pared rather than to take the trouble of manufacturing their own 

 wood-pulp paper. This was a good thing for the wasps, but 

 unfortunate for the vineyardist. 



It is more difficult to study the economy of the social 

 wasps than that of either the hive bee or ants. As most of the 

 species are very irritable and possessed of venomous stings, it re- 

 quires considerable tact and courage to investigate their habits 

 closely. 



The size of the communities varies at the season when they 

 are largest, and according to the species, from a few individuals 

 to many hundreds. In one large nest I counted 1,135 cells, and 

 since, as will be shown, the worker cells are used two or three 

 times in the summer, the colonies become very strong. This 

 count was made with the large bald-faced hornet (Vespa macu- 

 lata) but in some of the smaller wasps or yellow-jackets, like 

 Vespagermanica, the cells are even more numerous. In one nest 

 of the latter species, Mr. Marlatt tells me that he carefully esti- 

 mated that it contained about fourteen thousand cells. 



These communities of the social wasps, unlike those of the 

 hive bee and of ants, but like those of the bumblebees, have only 

 a temporary existence. On the approach of winter the males 

 and workers perish and the fertile females crawl into such pro- 

 tected situations as crevices in walls or under the bark of trees 

 and there pass the winter in a dormant state. At the opening of 

 spring each surviving female founds a new colony. At first she 

 performs the duties of both queen and worker; a small nest is 

 made, eggs are laid in it, and when the larvae hatch they are fed 

 and cared for by the queen until they reach maturity. This first 

 generation is composed entirely of workers. They relieve the 

 queen of the duties which belong to them and from this time forth 

 her only duty is to lay eggs. Sometimes she assists in the care 

 of the young but not in the construction of the nests. 



The essential part of a wasp's nest consists of a comb formed 

 of hexagonal cells similar in form to the cells of a honey-comb. 

 It differs, however, in several important respects from that of the 

 hive bee: The material of which it is made is paper instead of 

 wax; the comb consists of a single layer of cells instead of two, 

 and the cells are usually vertical instead of horizontal. In some 

 species the nest consists of a single comb with one or more stems 



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