]3o Bulletin Wisconsin Natural History Society. [Vol. 8, No. :>. 



for some distance over sunlit lawn where the grass was drier, to a 

 nest 20 m. (66') away, which they captured about 4:15 p. m. 



I believe it was Prof. W. S. Miller of Wisconsin University, 

 who was staying at the next house at the time, who looked over the 

 course with me and suggested that the very wet grass had had 

 something to do with the marked veering out of the straight 

 course, and to this I add the easily travelled smooth walk. It may 

 have been some old trail of their own slaves that they were fol- 

 lowing, or more likely the trail of the nest attacked, which they 

 and the scouting party thus attempted to follow through the wet 

 grass. It cannot be denied also that such original trail may have 

 had the same detour, made so faint by rains that the first party 

 of sanguinaries did not perceive the turn until they had become 

 confused in the wet grass. But 1 do not think they were depend- 

 ing on such a possible trail, which, if possible, must surely have 

 been faint after a 36-hour rain, since, in my familiarity with the 

 region, I had failed to note any well travelled route so thronged 

 in the past days by any species as to attract my attention to it as an 

 established route, altho I had been busy in the previous weeks in 

 locating all such travelled routes in advance. So I must deduce 

 that the ants' preference for easy travel over the dried-off tar, 

 tho' roundabout, was quite clearly the reason for the change of 

 route, inasmuch as no more ants continued to travel onward in rhe 

 wet. 



This example is not as clear-cut a case of choosing a round- 

 about course for the sake of ease only, as I should like to cite for 

 illustration, for this reason : — my notes read "The reds had great 

 ado to follow the curve, sometimes swerving too far into the 

 grass or too far out on the walk. This was particularly true at the 

 points where the ants turned to the curve and where they left 

 it. Some wanted to start for the bushes, got lost, as I judged from 

 their actions, and turned back" till they resumed the popular 

 route. This showed to my mind that there was such a complex 

 of trail scents here, that nothing but their eyes, perhaps, showed 

 them which way to go. Again, perhaps "they knew they were 

 being sent a long way round" ( Lubbock) and only the instinct to 

 keep with their fellows restrained them from trying marked cut- 

 offs even before they had learned by experience why the ants 

 ahead had curved their course. I suppose, then, the instinct to 



