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he fragments of the nest. This species is sometimes, though
rarely, made into slaves, as has been described by Mr. Smith. Although so
small a species, it is very courageous, and I have seen it ferociously
attack other ants. In one instance I found to my surprise an independent
community of F. flava under a stone beneath a nest of the slave-making F.
sanguinea; and when I had accidentally disturbed both nests, the little
ants attacked their big neighbours with surprising courage. Now I was
curious to ascertain whether F. sanguinea could distinguish the pupae of F.
fusca, which they habitually make into slaves, from those of the little and
furious F. flava, which they rarely capture, and it was evident that they
did at once distinguish them: for we have seen that they eagerly and
instantly seized the pupae of F. fusca, whereas they were much terrified
when they came across the pupae, or even the earth from the nest of F.
flava, and quickly ran away; but in about a quarter of an hour, shortly
after all the little yellow ants had crawled away, they took heart and
carried off the pupae.
One evening I visited another community of F. sanguinea, and found a number
of these ants returning home and entering their nests, carrying the dead
bodies of F. fusca (showing that it was not a migration) and numerous pupae.
I traced a long file of ants burthened with booty, for about forty yards,
to a very thick clump of heath, whence I saw the last individual of F.
sanguinea emerge, carrying a pupa; but I was not able to find the desolated
nest in the thick heath. The nest, however, must have been close at hand,
for two or three individuals of F. fusca were rushing about in the greatest
{223} agitation, and one was perched motionless with its own pupa in its
mouth on the top of a spray of heath, an image of despair, over its ravaged
home.
Such are the facts, though they did not need confirmation by me, in regard
to the wonderful instinct of making slaves. Let it be observed what a
contrast the instinctive habits of F. sanguinea present with those of the
continental F. rufescens. The latter does not build its own nest, does not
determine its own migrations, does not collect food for itself or its
young, and cannot even feed itself: it is absolutely dependent on its
numerous slaves. Formica sanguinea, on the other hand, possesses much fewer
slaves, and in the early part of the summer extremely few: the masters
determine when and where a ne
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