SOME SOCIAL WASPS 245 



cation on the insects of a permanent nature, so that it 

 could be certain that any one wasp was not accidentally 

 used in more than one experiment. 



In our work on the homing of Polistes pallipes, these 

 factors are all carefully considered; with permanent mark- 

 ings, with consideration of the age, experience and sex of 

 the subject, the results that these experiments show can be 

 explained without transcending human psychology. 



Polistes pallipes is a social wasp having three forms of in- 

 dividuals in a colony ; the queen or female, males and work- 

 ers. They are natural paper-makers, manufacturing the 

 paper for their nests from weathered wood. They mix the 

 woody pulp with a fluid substance from their mouths and 

 form it into the cells of their nests. The nests are made by 

 a single colony in one season, and all but the fertilized queen 

 perish with the cold of autumn. At the approach of winter 

 the fertilized females crawl into sheltered nooks and remain 

 there, in a dormant condition, until the warm weather of 

 spring awakens them. They at once construct a nest, lay an 

 egg in each cell, and, when the larvae hatch, they feed and 

 care for them until they transform into perfect insects. The 

 first brood consists of workers only, and these at once take 

 up the task of enlarging the nest and caring for the larvae, 

 for after this first brood has developed, the queen does noth- 

 ing but lay eggs. The workers are undeveloped females, and, 

 if the queen dies, the burden of egg-laying is assumed 

 by one or more of the workers. Later in the season, the 

 queens lay eggs which develop into perfect males and queens. 

 These mate, the males and workers die and the females 

 hibernate. (Lewis.) 



Throughout these experiments it is well to remember this 

 important point: that the queens spend the winter in some 

 sheltered nook, and hence have had some experience not only 

 in the previous autumn's roaming, but also in flying about 



