368 HALF HOURS WITH INSECTS. [Packard. 



the abdomen first of one aphis and then of another ; and 

 each as soon as it felt the antennae, immediately lifted up its 

 abdomen and excreted a limpid drop of sweet juice, which 

 was eagerly devoured by the ant. Even the quite j'oung 

 aphides behaved in this manner, showing that the action was 

 instinctive, and not the result of experience. It is certain, 

 from the observations of Huber, that the aphides show no 

 dislike to the ants ; if the latter be not present they are at 

 last compelled to eject their excretion. But as the excre- 

 tion is extremely viscid, it is no doubt a convenience to the 

 aphides to have it removed ; therefore probably they do not 

 excrete solely for the good of the ants. Although there is 

 no evidence that any animal performs an action for the 

 exclusive good of another species, yet each tries to take 

 advantage of the instincts of others, as each takes advan- 

 tage of the weaker bodily structure of other species." 



That there is much difference among individual ants. Dr. 

 Lincecum has affirmed in his article on the Agricultural Ant 

 in the eighth volume of -the "American Naturalist." "I 

 have recently discovered," he sa^s, "a great difference in 

 their mental operations and capacities. Individuals there 

 are which possess great intellectual superiority to the com- 

 mon laboring classes, which is manifested in the fact that 

 they assume the leadership in all their important public 

 works and army movements. Some are much more saga- 

 cious and cautious in avoiding traps and dangerous contri- 

 vances set for them by the scarcely superior human genus. 



"One of our Germans invented a very destructive ant trap. 

 It is set over the entrance to their city, and is so contrived 

 that going or coming it is sure to entrap them ; but not all 

 of them. Occasionally a well formed fellow is observed to 

 arrive at the top of the precipice, where he stops and gravely 

 and cautiously sui-veys the awful abyss below, filled with 

 frantic and terribly distressed thousands who have incau- 

 tiously precipitated themselves into inevitable ruin, and after 



16 



