INTELLIGENCE IN INSECTS 207 



conclusions in the study of animal intelligence, one which 

 is responsible for a great multitude of stories of doubtful 

 value. Observations may have been recorded faithfully 

 and- accurately, but where they have not been made by in- 

 vestigators thoroughly acquainted with the general behavior 

 of the forms observed, mistaken interpretations are almost 

 certain to arise. On the other hand, one is tortured by the 

 feeling that our experimental methods often fail to give us a 

 true measure of an animal's possible attainments, and that 

 it is just in meeting exceptional situations which occur in 

 the animal's natural course of life that the highest manifesta- 

 tion of its intelligence is reached. 



A factor which markedly affects the behavior of many 

 insects, especially the social ones, is the influence of numbers. 

 Small stocks of bees, according to Buttel-Reepen, lose their 

 spirit and allow themselves to become the prey of moths 

 and robber bees which are not so easily tolerated by larger 

 stocks. They work with less vigor and fight with less 

 courage, as if conscious of the fact that in numbers there is 

 strength and that their number is small. Forel says of ants 

 that "the courage of each ant grows in proportion to the 

 number of her comrades or friends and diminishes in just 

 the proportion that she is isolated. . . . The same 

 worker ant, which in the midst of her associates, is ready 

 to face death ten times over, when alone and twenty steps 

 away from her nest, becomes cowardly, avoids the least 

 danger, and seeks safety in flight from an ant much weaker 

 than herself." In regard to Formica sanguined Wasmann 

 states that "if a numerous population inhabits a rotten 

 fir stump, on the surface of which we find some of the 

 ants running about, a gentle kick will at once call forth a 

 whole army ready for the fray. In a moment the whole 

 surface of the stump is covered with thousands of ants 



