EXPERIMENTS ON CO-OPERATION. 371 
last she went round the outside of cup 1, instead of 
going straight to the spot where I had placed the bit 
‘of wood. 
On January 9 again I watched her under simi- 
lar. circumstances. From 9.35 to 1.40 she made 55 
journeys to and fro, carrying off a larva each time; but 
during this period only one other ant found the larve. 
In the afternoon of the same day I watched the 
ant which had been under observation on the 3rd Jan. 
From 3.27 to 9.30 she made forty-two visits, during 
which time only four other ants came to the larva. 
On January 10 I watched the same ant as on the 
4th. Between 11 a.m. and 10 p.m. she made no less 
than ninety-two visits; and during the whole time only 
one strange ant came to the larve. 
On January 18 I put out some more larve in the 
small porcelain cups. Between 8 and 9 both these ants 
found them, and kept on coming all day up to 7 P.M., 
when I left off observing. There were a good many 
ants wandering about in the box; but up to 4 o’clock 
only four came to the larve. Two of them I impri- 
soned as usual; but two (which came at 4.30 and 4.36) 
I marked. These went on working quietly with the 
first two till I left off observing at 7 p.M.; and during 
this latter time only three other ants found the larve. 
On January 31 I watched another specimen. At 
9.14 I put her into a small cup containing a number of 
larvee. She worked continuously till half-past seven in 
the evening, when I left off watching. During that 
time she had made more than ninety journeys, carrying 
each time a larva to the nest. During the whole time 
not a single other ant came to the larve. 
Again, on February 7, I watched two ants in the 
same manner. At 7 4.M. I put some larve in the small 
china cups. Up to 8 noants hadcometothem. Soon 
after 8 I put two marked ants, neither of them being 
the same as these whose movements are above recorded. 
