a^ Sw ■s5?i 



THE IXTEREST IN INSECTS 



393 



Animal Intelligence Again. 



BY HEXRY O- FALK oF SCKIPI'S IXSTITU- 

 TION FOR BIOLOGICAI, RESEARCH OF THE 

 UNIVERSITY OF CALIFORNIA. 



[illustrations by STUART s. taber]. 

 I was mildly puzzled. I had seen 

 flies, spiders, and moths in the house ; 

 occasionally also a flea, a so\v-bug, or 

 a centipede ; but that cra\vling thing 

 on the wall of our dining room looked 

 like some shapeless parazoan. Closer 

 attention showed that the focus of mv 







T^s-'^^e 



"THIS 'LANGI'AGE- IS SPOKEN WITHOUT 

 EDLXATION." 



interest was only a harmless piece of 

 cake. Incredulity challenged sense ex- 

 perience. The walls of the room are 

 dark brown, and what I am relating oc- 

 ciuTed in the evening ; so conditions of 

 place and time greatly assisted in the 

 illusion, if they did not entirely pro- 

 duce it. A piece of cake, three-quarters 

 of an inch by one-half an inch, was 

 making steady progress up the wall. 



I rose from the dinner table resolved 

 to get more light on this singular event. 

 Has the reader guessed or must I tell 

 him that the motive power behind the 

 cake was a dozen or so ants? The 

 burden was many times larger and 

 heavier than the combined size and 

 weight of this self-constituted gang. 

 Any working at cross-purposes would 

 have been fatal to this social under- 

 taking. But co-o])eration was seem- 



:^^'=*l^ '^ ^^ 8^ ^^ ^ §^ ^ ^ 



ingh' perfect. The course they took is 

 sketched m the accompanying dia- 

 gram. I followed the progress of the 

 work in mute wonder. Yes, I thought 

 I discerned an underlying purpose. The 

 ants did not choose the easiest way, 

 nor did they wander about aimlessly. 

 Quite the contrary. They heaved and 

 tugged with a will, steering straight 

 ahead for their destination despite ob- 

 stacles and depressions. As the dia- 

 gram shows, the trail followed was the 

 shortest and most direct, although not 

 the easiest. 



Other ants scurried up and down the 

 wall. Most, of them paid little or no 

 heed to the extraordinary labors of 

 their neighbors. But now and then 

 one of the wayfarers approached, and 

 upon finding a vacant place somewhere 

 on the edge of the cake, took hold and 

 thereby incorporated itself into the 

 gang. Thus the numbers swelled, each 

 addition resulting in augmented eft'ec- 

 tiveness. 



The aft'air sailed along smoothlv 

 enough until a corner of the ceiling 

 was reached. Here is an aperture due 

 to imperfect joining of the ceiling with 

 the wall. Through this the ants came 

 into the house, indicating the presence 

 of a nest somewhere beyond, and here 

 they dragged their precious burden. 

 The diameter of the cake was easilv 

 twice or perhaps three times the width 

 of the crack. My ants addressed them- 

 selves to the impossible task of pulling 

 the cake through it. Retracing their 

 steps a little, they crossed the mouth 

 of the aperture, crept along one of its 

 lips, then along the other, entered the 

 crevice pulling the cake after them, or 

 remained outside pushing the cake be- 

 fore them — all to no avail. For three 

 hours the ants strove to deposit the 

 cake in the aj)erture. I made observa- 

 tions at frequent intervals but the sit- 

 uation remained unchanged. The jiiece 



