246 WANT OF INGENUITY 
could ascend c, and, passing over D, descend upon the 
larve. I then put some specimens of Lasius niger to 
the larve, and soon a large number of ants were en- 
gaged in carrying off the larve. When this had con- 
tinued for about three hours, I raised pD 53; of an inch 
above A. The ants kept on coming and tried hard to 
reach down from D to A, which was only just out of 
their reach. Two or three, in leaning over, lost their 
foothold and dropped into the larve; but this was 
obviously an accident; and after a while they all gave 
up their efforts, and went away, losing their prize, in 
spite of most earnest efforts, rather than drop ;8, of 
an inch. 
At the moment when the separation was made there 
were fifteen ants on the larve. These could, of course, 
have returned if one had stood still and allowed the 
others to get on its back. This, however, did not. 
occur to them; nor did they think of letting themselves 
drop from the bottom of the paper on to the nest. 
Two or three, indeed, fell down, I have no doubt, by 
accident ; but the remainder wandered about, until at 
length most of them got into the water. After a time 
the others abandoned altogether as hopeless the attempt 
to get at the larve. 
I waited about six hours, and then again placed the 
