1941] Experiments in Vespine Colonies 17 
About eight hours of confinement sufficed to persuade the 
adults to remain with the nest and continue their normal 
activities. 
Once established in the new environment, a colony would 
not voluntarily desert despite further treatment with anses- 
thetic. One colony of Dolichovespula arenaria Fab. was 
periodically treated with ether that I might remove a 
portion of the nest wall for observation purposes. These 
did not leave the nest although they were free to do so. 
As a result of enlarging the nest, one colony of Dolicho- 
vespula maculata Linn, expanded the brood comb until it 
came into contact with the observation window in the hive. 
The paper nest wall was removed by the wasps and the 
glass served as the wall. A similar observation was figured 
by A. H. Clark (2). This is evidently a normal method of 
building the nest into contact with any surface, as nests 
collected from rafters and walls of buildings exhibit the 
same structure. 
Customarily new comb is built below the existing tiers of 
comb. In the circumscribed space of the compartments this 
could not be done, so the hornets increased the area of each 
comb by adding cells to the periphery. 
Because of the limited vertical expansion in the compart- 
ments, some of the Dolichovespula colonies were forced to 
use the floor of the hive as the nest floor, without any paper. 
Lacking any excavating instinct, the wasps made no effort 
to remove the floor of the hive. 
The nests gradually assumed a hemispherical shape. In 
these nests, the entrance was eventually made opposite the 
escape aperture of the hive and on the floor of the hive. 
Old wasp comb and paper was supplied to assist certain 
colonies in gathering paper material. None would accept 
this paper. 
Species of Vespula will also respond to hive conditions 
without the accustomed dampness of the earth. Few notes 
were made on this genus as observations were made too late 
in the season. 
Wasps returning from the fields invariably return directly 
to the home window. In many cases, however, they would 
fail to select the proper hive compartment. Even when 
there were two or more species in a hive, they would re- 
