ANTS— MEMORY. 
41 
so considerable a distance, this hypothesis does not 
seem probable, and the only other one open to us is that 
the ants remembered the site of their former home for a 
period of twelve months. And this conclusion is rendered 
less improbable from a statement of Karl Vogt in his 
6 Thierstaaten, 5 to the effect that for several successive 
years ants from a certain nest used to go through certain 
inhabited streets to a chemist’s shop 600 metres distant, 
in order to obtain access to a vessel filled with syrup. As 
it cannot be supposed that this vessel was found in suc- 
cessive working seasons by as many successive accidents, 
it can only be concluded that the ants remembered the 
syrup store from season to season. 
I shall now pass on to consider a class of highly re- 
markable facts, perhaps the most remarkable of the many 
remarkable facts connected with ant psychology. 
It has been known since the observations of Huber 
that all the ants of the same nest or community recognise 
one another as friends, while an ant introduced from 
another nest, even though it be an ant of the same 
species, is known at once to be a foreigner, and is usually 
maltreated or put to death. Huber found that when he 
removed an ant from a nest and kept it away from its 
companions for a period of four months it was still recog- 
nised as a friend, and caressed by its previous fellow- 
citizens after the manner in which ants show friendship, 
viz., by stroking antennae. Sir John Lubbock, after re- 
peating and fully confirming these observations, extended 
them as follows. He first tried keeping the separated ant 
aw T ay from the nest for a still longer period than four 
months, and found that even after a separation of more 
than a year the animal w r as recognised as before. He re- 
peated this experiment a number of times, and always 
with the same invariable difference between the recep- 
tion accorded to a foreigner and a native — no matter, 
apparently, how long the native had been absent. 
Considering the enormous number of ants that go to 
make a nest, it seems astonishing enough that they should 
be all personally known to one another, and still more 
astonishing that they should be able to recognise members 
