204 INTELLIGENCE IN INSECTS 
we have intelligent behavior rising to a level to which some 
would apply the term rational. Tor the act may be held to 
afford evidence of the perception of the relation of the means 
employed to an end to be attained, and some general con- 
ception of purpose.” Truly a “tool using animal!’ But 
in estimating the psychic aspect of the performance we 
must bear in mind that the act is one which borders closely 
upon the normal instinctive behavior of the insect. The 
seizure of pebbles in the mandibles and the packing in of 
dirt are parts of the instinctive process of filling up the hole. 
The wasp combines two features of its hole-fillmg instinct in 
a rather unusual way. Does she really perceive the relation 
of means to end? I am not so sure that she does. 
Many readers who peruse this chapter will miss the 
wonderful accounts of insect ingenuity which they may 
have expected to find. The literature of insect behavior 
contains these in abundance. Run through the files of 
Nature, Science Gossip, Der Zoologische Garten, La Nature, 
The Zoologist, the older numbers of the Annals and Magazine 
of Natural History, and The American Naturalist, the 
various entomological journals, and works of travellers 
with a leaning toward natural history; and peruse the many 
volumes that have been written on the instincts and intelli- 
gence and reasoning power of animals, and you will encounter 
an enormous mass of material, some of it carefully recorded, 
much of it not, more of it vitiated by anthropomorphic 
interpretation which one cannot help feeling has biased the 
observer in his account of the facts, but the data that can be 
employed in drawing conclusions regarding the degree of 
intelligence shown by the forms observed is disappointingly 
small. Animals are observed overcoming obstacles or meet- 
ing unusual situations, and the occurrence is straightway 
recorded as an illustration of sagacity, something for which 
