THE CAMPANULAR WASP — THE PASTEBOAKD WASP. 279 



The wasp itself is prettily marked, and although it is variable 

 in coloring, can be recognized by the black anchor-shaped mark 

 on the clypeus, and the squared black spot on the segments of the 

 abdomen. 



Another species of British Tree Wasp is the Campanular 

 Wasp {Vespa sylvestris), a species which has received a multitude 

 of scientific names, but which is not variable in color as that 

 which has just been mentioned. Though it has a wider distri- 

 bution than the Norwegian wasp, it is scarcely so plentiful an in- 

 sect, and is remarkable for an occasional habit ef making a sub- 

 terranean nest like that of the common wasp. The Northern 

 Wasp ( Vespa horealis or arborea) is another of the pensile wasps, 

 and is mostly found in the north of England and Scotland. Its 

 nest is built in fir-trees. I may perhaps mention that the tree 

 wasps may always be distinguished from their subterranean breth- 

 ren by the color of the antennae, workers and females having the 

 scape black in the ground wasps, and those which build in trees 

 having it yellow in both sexes. 



The nest of the tatua, which has recently been described, must 

 not be confounded with that of the Pasteboard Wasp {Charter- 

 gus nidulans), although both insects inhabit the same country, and 

 the nest of the latter bears a great external resemblance to the 

 pendulous nest of the tatua. But, when examined closely, this 

 nest is seen to have a remarkable addition to its structure, the 

 hole through which the branch is passed being very large, so as 

 to permit the nest to swing freely in the wind. In most speci- 

 mens of these nests the hole is simply made through the thick 

 upper end of the structure, but in a few examples the pasteboard- 

 like substance is so moulded that it looks as if a ring had been 

 added to the top of the nest. 



The dimensions of the Chartergus' nest are extremely variable, 

 each structure appearing to be capable 'of unlimited enlargement. 

 The mode by which the wasps increase the size of their pensile 

 home is equally simple and efi&caoious. When the number of 

 the inhabitants becomes so large that a fresh series of cells is re- 

 quired, the insects enlarge their home with perfe(ct ease, and at 

 the same time without destroying its symmetry, a point which is 

 often forgotten when human architects undertake the enlargement 

 of some fine old edifice. Taking the bottom of the nest as the 



