24 
•xioned by both. In the corn, from a hundred hills chosen as fairly 
representative of the whole field 2156 ants were taken, an average 
of twenty-two to the hill, fifty-two of the hundred hills being in- 
fested by them. In the same hills 1507 root-lice were found, an 
average of fifteen to the hill, forty-three of the hills being infested. 
Each ant's nest contained on an average forty-one ants and thirty- 
five root-lice, — less than one root-louse to each ant. The winged lice 
in these hundred hills averaged in number twenty-seven per cent, 
of all the adults. Collections made on higher and drier parts of the 
field were compared with those from lower and wetter portions, but 
gave no marked difference in respect either to the ants or aphids, or 
to the ratios of winged to wingless adults. 
Observations made in this field correspond precisely, it will be 
seen, to those reported from the Barto fields with reference to the 
total disappearance, late in May, of ants and aphids from oats grown 
on old corn ground. 
Additionai, MisceivIvAneous Observations. 
April II, at Bradford, an ant's nest was explored, the burrows 
of which extended throughout an area approximately three by four 
feet, and to depths varying from one to four inches. Ants were dis- 
tributed everywhere through the soil within these dimensions, but 
all the aphis eggs seen were collected at one place. 
April 12, a nest of Lasiiis alicnus, around which a few young 
smartweeds {Polygonum persicaria) about one inch high were scat- 
tered, was watched by Mr. Kelly for two hours and a half. An ant 
coming up with a young root-louse in its mandibles carried this 
about two feet and placed it on a smartweed very near the ground, 
and the root-louse, after crawling about half an inch, thrust its beak 
into the plant. Six more ants transferred a single root-louse each 
to smartweeds above ground within the next twenty minutes. In 
about an hour and a half one of the ants returned its root-louse to 
the nest, and thirty-five minutes later all had been carried back. One 
of these ants, which was so marked that it could be recognized on 
its return, recovered and carried to the nest the same root-louse 
which it had previously brought out. 
Another nest of the ants was carefully explored on the 13th. 
The burrows were found to vary in diameter from one sixteenth to 
three eighths of an inch, and to range from one to six inches below 
the surface. In a cell a quarter of an inch in diameter were many 
eggs and a few young of the corn root-aphis. When these were dis 
turbed the ants seized them and retreated to more distant parts of 
