INTELLIGENCE. 233 



mously with the species. Among the ants the traits of character recogniza- 

 ble are anger, hate, devotion, activity, perseverance, greediness, boldness, 

 discouragement, and fear. Thus, in studying the habits of insects it is 

 necessary to take into consideration their mental faculties as well as their 

 organs of sense. 



Memory and general intelligence of wasps. — The Peckhams 

 (1887:121) concluded that wasps have a very good memory, remembering 

 for ten days the characteristics of the glass of a window through which 

 they were accustomed to fly. The memory varied greatly in different indi- 

 viduals; in the color experiments many wasps would fly into the false 

 entrance several times, while others would fly in but once, and still others 

 would only hover over it before turning to the true opening. When blades 

 of grass were placed across the entrance to the nest, not one of more than 

 300 wasps made any attempt to remove them, in spite of the fact that they 

 seriously hindered them and were less than a usual load in weight. Even 

 when going out without loads no endeavor was made to get rid of the ob- 

 stacle. They noted two classes of intelligent action among the Hymen- 

 optera, which are sufficiently distinct to be considered separately (1905:301). 

 The first includes those acts performed by large numbers in a similar 

 fashion under like conditions, while in the second each act is an individual 

 affair. The first is exemplified by Fabre's experiment with Osmia, in which 

 he took 2 dozen nests in shells from a quarry, where the bees had been 

 nesting for centuries, and placed them in his study along with some empty 

 shells and hollow stems. When the bees came out in the spring, nearly all 

 chose the stalks as better suited to build in than the shells, thus evidencing 

 an intelligent adaptation to new conditions. The second case is illustrated 

 by a wasp {Pompilus scelesius) which tried to drag its prey into the opening of 

 a nest that was too small. After several vain tugs, it was carried to a place 

 of safety up among some clover blossoms, and after some fifteen minutes 

 of walking and brushing herself, the wasp set about making the hole larger. 

 During this period she must have carried in mind the idea of doing a neces- 

 sary act outside of the ordinary routine, and it is also suggestive that the 

 hole when enlarged was exactly what was needed. 



Memory of place in bees. — In an extended critique of Bethe's paper 

 (1898: 15) which endeavored to establish the hypothesis that bees are merely 

 reflex machines, Buttel-Reepen (1900:96, 1907) discussed the evidence 

 chiefly under three heads, namely, (1) the hive odor and the reactions 

 resulting from it, (2) the means of communication in bees, and (3) memory 

 of place in bees. The latter alone is directly connected with the present 

 inquiry and hence summarized here. Bethe assumed that — 



"Bees are led back to the hive by a force entirely unknown to us. This force does 

 not adhere to the hive itself, and it does not lead bees back to the hive itself, but to 

 the place in space which the hive usually occupies. It does not act at boundless 

 distances. It is an old experience of bee-keepers that they can take a colony to another 

 stand without fearing that the bees will return to the old place, if the new spot is 

 only more than six kilometers from the old. It follows, then, that this force acts at 

 most at a distance of six kilometers, since the impulse to return to the hive is the strong- 

 est of all impulses in bees. But I believe that the zone of action of the force is not a 



