Wasps, Bees, and Ants 
5°7 
places in our houses. Wasps of this genus are not infrequently parasitized 
by the remarkable Stylopid beetles (Fig. 403) Xenos, of which an account is 
given on p. 295. 
Fig. 713.—Queen-nest of yellow-jacket, Vespa sp.; specimen at right in normal con¬ 
dition; at left cut open to show brood-cells. (Natural size.) 
Only one species of Polybia occurs in the United States, and that one, 
P. flavitarsis (PI. XII, Fig. 12), is found only on the Pacific coast. It is 
common in California. It is readily distinguishable from the other social 
wasps by its slender pedunculate basal abdominal segment and the small 
button-like shape of the rest of the abdomen. It builds a single-comb, 
unenveloped nest, like that of Polistes, but not reaching the diameter of 
the broad disk-like Polistes comb. 
It has been mentioned that the social wasps feed their young (larvae) 
chewed insects. Differing from most of the solitary wasps, the social kinds 
do not store up food for the young, but collect and bring it constantly through 
the life of the larvae, a period of from eight to fifteen days. This food con¬ 
sists of the partially masticated remains of various insects pursued and killed 
by the queen or workers. The queen brings food only for the larvae of the 
first small spring brood. 
The adult wasps are more catholic as regards the palate; they feed on 
insects or decomposing animal substances—fish especially attract them— 
and on exposed sweet substances, as sirups, preserved fruits, etc. 
The paper-making and nest-building are industries whose details can 
only be touched on in our limited space. The paper is not only made of 
