366 WASP STUDIES AFIELD 



door was so narrow that every time she came out of the 

 burrow she knocked the spider down the hill. After pro- 

 longed struggles her better judgment overcame this in- 

 stinct for a moment, for she finally carried her prey to a 

 point where the bank sloped gradually, then dragged it 

 back horizontally and let it rest on a ledge three inches above 

 the burrow. But here the conflict between instinct and in- 

 telligence recurred, for when again she tried to take the 

 spider into her burrow she returned to her old habit of a 

 final inspection of the nest, and lost her prey as before 



With these few facts as examples of types of variation 

 in behavior, plasticity of instinct, memory, etc., we can see 

 at once how little the theory of Bethe and the tropism 

 theory have to offer toward satisfactorily explaining the 

 phenomena. Forel, 3 conservative as he is, explains the ac- 

 tions of such creatures far better in these words : 



"Insects, therefore, reason, and the most intelligent 

 among them, the social Hymenoptera, especially the wasps 

 and ants, even reason much more than one is tempted to 

 believe when one observes the regularly recurring mechan- 

 ism of their instincts. To observe and understand these 

 reasonings well, it is necessary to mislead their instinct. . . 

 Further, one may remark little bursts of plastic judgment, 

 of combinations extremely limited, it is true which, in 

 forcing them an instant from the beaten track of their 

 automatism, helps them to overcome difficulties, to decide 

 between two dangers, etc. 



"From the point of view of instinct and intelligence or 

 rather of reason, there are not, therefore, absolute contrasts 

 between the insect, the mammal and the man. In the in- 

 sect, the inherited automatisms play by far the preponderat- 

 ing part, developed and specialized to an unheard-of point, 

 and, curiously enough, often coming to produce very analo- 



3 The Senses of Insects. Translation, p. 119. London. 1908. 



