444 THE AMERICAN NATURALIST. [VoL. XXXV. 
interrupted their repairs to shampoo and kiss the interlopers and 
again they tugged them by a leg or an antenna, sometimes in 
one direction, sometimes in another. And again I was forced 
to conclude that the Leptothorax workers wished to dissuade 
their big hosts from trespassing on their property. At any 
rate, the Myrmicas changed their plans and retreated to another 
part of the nest, just as the other parties had done on former 
occasions. The Leptothorax then continued their repairs. By 
6 P.M. the walls had been rebuilt and the cell had the appearance 
of Fig. 7. The original entrance, 7, had been much narrowed 
so as to exclude all but the slender-bodied inhabitants of the 
chamber. 
At 7 o'clock on the following morning (August 28) the 
Leptothorax nest was found in statu quo, except that the queen 
had laid three more eggs during the night. By noon, however, 
the Myrmicas had again broken into the cell, so that at 4.30 P.M. 
the wall was torn down in several places. Nevertheless, the 
ever alert guest ants had piled up the earth so that the Myr- 
micas could scarcely squeeze between it and the glass roof- 
pane. The inroads of the Myrmicas had been so extensive, 
however, that even as late as 7 P.M. the nest presented the 
appearance of Fig. 8. 
By 7 a.m. on the following day (August 29) the nest had been 
almost entirely rebuilt, as shown in Fig. 9. The Leptothorax 
must have labored during a large portion of the night. They 
had remodeled the nest, giving it a circular form, whilst appar- 
ently retaining the old opening at r. Besides this opening 
they had two others at z z, which were underground passages. 
The ants could be seen diving into these and anon reappearing 
within the circular chamber, the bottom of which had been 
sunk still deeper in the soil The neat little nest now Com 
tained ten eggs. From day to day the Myrmicas had been 
widening their galleries, as is readily seen by comparison of 
Figs. 4 to 9, so that only small pillars of earth remained to 
support the roof-pane around the Leptothorax cell. 
On succeeding days essentially the same conditions as those 
above described were repeated with slight differences in detai 
For the sake of completing the history of the double nest, the 
