178 ASSOCIATION OF ORGANISMS—THE WEB OF LIFE 
times occur. More observations are necessary in order to settle 
the question. Lord Avebury makes the following conjectures 
(in Ants, Bees, and Wasps) as to the past history of Anergates: 
—‘ We may safely conclude that in distant times their ancestors 
lived, as so many ants do now, partly by hunting, partly on honey; 
that by degrees they became bold marauders, and gradually took 
to keeping slaves; that for a time they maintained their strength 
and agility, though losing by degrees their real independence, 
their arts, and even many of their instincts; that gradually even 
their bodily force dwindled away under the enervating influence 
to which they had subjected themselves, until they sank to their 
present degraded condition—weak in body and mind, few in 
numbers, and apparently nearly extinct, the miserable repre- 
sentatives of far superior ancestors, maintaining a precarious 
existence as contemptible parasites of their former slaves.” 
Ants not only keep cattle and slaves, but are also known, in 
many cases, to entertain quite a number of insect guests, which 
they feed and otherwise look after, their attentions being pro- 
bably often rewarded by some sort of sweet substance produced 
by their visitors, though this does not appear to be invariably the 
case. Beetles are especially common among such true guests, 
and many species (as also of other sorts of insect) are to be 
found nowhere else, being then known as ants’-nest insects 
(myrmecophilous insects). They often somewhat resemble their 
entertainers in appearance, and are fully versed in the ways of 
the nest. The latter point is well illustrated by the way in which 
they stroke ants that have returned from foraging, to induce them 
to disgorge some of the honey with which the crop is distended 
(fig. 1127, A). One very remarkable case has been described 
in which certain ants (Zaszus) carry about mites on their bodies, 
feeding them from time to time, and otherwise treating them 
with great consideration, though apparently without deriving any 
corresponding benefit. 
Besides the true guests just mentioned, there may be also 
various sorts of tolerated guest, which the ants treat with more 
or less indifference. A case in point is afforded by a small ant 
(Formicoxenus nitidulus), which is permitted to live unmolested 
in the hills of the large Horse-Ant (Formica rufa). A somewhat 
amusing instance is that of a species of Tassel-tail (Grasszedla 
polypoda), which maintains itself in the nest of a kind of ant 
