130 EXPERIMENTS WITH PUPA. 
they would be amicably received in the nest from 
which their nurses had been taken, but not in their 
own. 
In the first place, therefore, I put, on September 2, 
1877, some pups from one of my nests of Formica 
fusca with a couple of ants from the same nest. On 
the 27th I put two ants, which in the meantime had 
emerged from one of these pups, back into their own 
nest at 8.30 a.M., marking them with paint as usual. 
At 9 they seemed quite at home; at 9.30, ditto; at 
10, ditto; and they were nearly cleaned. After that 
I could not distinguish them. 
On the 29th another ant came out of the pupa- 
state; and on October 1 at 7.45 I put her back into 
the nest. She seemed quite at home, and the others 
soon began to clean her. We watched her from time 
to time, and she was not attacked; but, the colour 
being removed, we could not recognise her after 9.30. 
On Jnly 14 last year (1878) I put into a small glass 
some pup from another nest of Formica fusca with 
two friends. 
On August 11 I put four of the young ants which 
had emerged from these pupe into the nest. After 
the interval of an hour, I looked for them in vain. 
The door of the nest was closed with cutton-wool; so 
that they could not have come out; and if any were 
being attacked, I think we must have seen it. I 
believe, therefore, that in the meantime they had been 
cleaned. Still, as we did not actually watch them, I 
