38 OUTLINES OF ENTOMOLOGY. 



Like the bees, this tribe of wasps has its social and its solitary 



species. 



The best representative of the former is the Bald-faced Hornet 

 (Vespa maculata, Linn.,) an insect with whose large gray paper nests 

 often eight or ten inches in diameter and whose fierce sting every 

 school-boy is familiar. The habits of this species are much like those 

 of the Humble bees. The perfect females, only, hibernate, and when 

 the spring is well advanced each one forms a few cells, mainly from a 

 glutinous secretion from the mouth, but apparently mingled with a 

 little woody fiber. These are attached by a slender pedicel, with the 

 opening downward, to a branch of some low tree or similar and secluded 

 support. The eggs are glued into the cells, and the young larvae, with 

 heads down, are at first fastened in the same manner, but as they grow 

 the swelling of the segments next the head serves to keep them in 

 position. 



These first larvae speedily develop into workers and release the 

 queen from her labors. The tier of cells is added to on all sides, and 

 over it is built an umbrella-like roof, the materials being mainly fibers 

 of weather-beaten wood, collected from old fences and unpainted build- 

 ings. This is masticated and mingled with the fluids from the mouth, 

 and when thinly spread dries into a strong water-proof paper. 



As the season advances and workers increase, successive tiers of 

 cells are built, attached by strong silken pillars to those above, with gal- 

 leries between, through which the wasps can easily move when caring 

 for the young. The outer envelope too is enlarged and brought down 

 at the sides, and finally made to completely enclose the nest. Late in 

 summer a brood of perfect males and females is produced, and upon 

 the approach of cold weather the ingenious little home is deserted, the 

 mature insects, it is said, first stinging to death any larvae or pupae that 

 remain, dragging them ruthlessly from their cells and casting them to 

 the ground. . 



Some species of the genus Vespa for example, the smaller and 

 more brightly colored " Yellow jackets "have their homes, like the 

 Humble bees, underground. 



The nests of the species belonging to the genus Polistes consist of 

 a single tier of from ten to twenty or thirty cells, built in some shel- 

 tered situation and without any external enclosing wall. The species 

 are more slender in form than the hornets, and are mostly of rust-red 

 or brown colors. From their habit of attaching their clusters of open, 

 gray paper cells under the cornices or window sills of our dwellings, 



