ANTS AND THEIR HELPLESS CHILDREN 283 
that in one case at any rate a queen which he kept 
artificially (Myrmica ruginodii) did bring up some 
young workers from her eggs.* 
There is another way, however, in which new 
nests begin, and this is when an old nest is over full, 
or when the leaves and sticks begin to decay, and 
the carcasses of insects and of dead ants which have 
been thrown out of the nest make the home un- 
healthy. In either of these cases some worker sets 
off and finds a spot for a new nest ; this found she 
comes back, and seizing another ant in her mandibles 
carries her off to the chosen place. These two again 
return, each carrying another, and so a little band of 
workers is collected. 
Then they set to work. One ant begins to dig a 
hole with her front legs, throwing out the dirt behind 
much as a dog does ; another and another follow in 
aer train, and the work goes on merrily, while others 
are still going to and fro to the old nest and carry- 
ing in new recruits. As soon as the tunnel becomes 
too deep for the earth to be kicked out, the exca- 
vators bite out pieces with their mandibles and carry 
them in little pellets outside the hole to form the 
upper part of the nest. Meanwhile others are fetch- 
ing sticks and leaves to prop up* the galleries and 
roof the chambers ; and so the dome rises above, as 
the firmer part of the nest is being scooped out below. 
And now the migration goes on apace ; no ant 
seems to leave the old nest willingly, but as soon as 
she is carried to the new one the general enthusiasm 
seizes upon her, and she sets to work to dig and 
build, or runs back to carry another as eagerly as 
* " Habits of Ants," Science Lectures, p. 92. 
