28cr WASP STUDIES AFIELD 



the home. There is, as the experiments seem to show, 

 a limit to the distance from which they have the power to 

 return. If a wasp is taken far enough away* from home 

 it can be lost, even though it be within the range of its 

 physical endurance. Now if they were endowed with some 

 mysterious power, or sixth sense, or magic or unknown 

 force or what not, they should return to the nest, regardless 

 of the distance they have to traverse, so long as it is easily 

 within their physical power. Furthermore, since Polistes 

 do not return at night, as Smith says, then the suggested 

 unknown power is proved of known impotence. Again, if 

 the mysterious sixth sense were adequate, we should see 

 all of the wasps drawn, as if by magic, at the same time to 

 the nest, and we would not find such vast variations in the 

 time for their return as from twenty-two minutes to two 

 and one-fourth days. This unknown force of Bethe and 

 others should transcend time and space, but our experi- 

 ments throughout leave every indication that age, experience, 

 memory and perseverance are the factors that bring Polistes 

 pallipes back to their homes, and when they are removed 

 beyond the distance within which these faculties are ade- 

 quate, they are lost. Their case is, in fact, quite analogous 

 to that of human beings, who, when lacking these factors 

 of age and experience, perseverance and memory, are easily 

 lost. 



Polistes rubiginosus Lept. 



We have seen these wasps out, on various occasions, 

 from April 2 to October 13, and yet we have only a few 

 desultory stories out of their whole life history. 



One April morning, while looking down from a clay bank 

 into a pond ten feet below, we saw a P. rubiginosus at- 

 tempting to alight on the surface of the stale water. We 



