THE SENSE OF DIRECTION IN WASPS. 219 



lias also been shown that in spite of all this care they frequently 

 have trouble in finding their way about. All these facts have 

 led us to conclude that wasps are guided in their movements 

 by their memory of localities. They go from place to place 

 quite readily because they are familiar with the details of the 

 landscape in the district they inhabit. Fair eyesight and a 

 moderately good memory on their part, are all that need be as- 

 sumed in this simple explanation of the problem. 



"When working with the social wasps some years ago we were 

 struck by the rapid way in which they entered and left the nest. 

 This, however, is only an apparent exception to the rule. We 

 have seen the young workers of Polistes fusca make repeated 

 locality studies when they first began to venture away from 

 home, but as they occupy the same nest all summer they of 

 course grow more and more familiar with their surroundings, 

 until they become so thoroughly acquainted with them that they 

 can find their way without the least difiiculty. We have no 

 doubt that with them, as with the solitary wasps, the faculty is 

 not instinctive, but is the direct outcome of individual experi- 

 ence. 



