SOCIAL LIFE 251 



which hart)our these guests " care more " for the beetle 

 grubs than for their own. But this mode of expression 

 attributes to the ants motives for behaviour which do not 

 necessarily follow from the observed actions, for it is very 

 doubtful how far the worker- ants, whose responses are 

 mostly made to tactile and olfactory stimulations, dis- 

 tinguish between the various inmates in the nest with which 

 they come into touch. A creature, be it sister-ant or 

 guest-beetle, which gives the tap on the head to which the 

 normal response is regurgitation of food, is fed as a matter 

 of course by any worker in the nest. 



This conclusion is supported by the relation between 

 several species of Lasius and certain tiny mites (Anten- 

 nophorus) which are carried about and fed by the worker- 

 ants although, unlike most of the guest-beetles, they furnish 

 the ants with no food substance in recompense. Janet 

 (1897) has described how a worker may be observed to 

 carry along the galleries of an underground nest of Lasius, 

 three of these mites, one with its back downwards clinging 

 to the ant's neck with its three hinder pairs of feet, and the 

 other two holding on one on either side of her abdomen. 

 The long front legs of the Antennophonis are used to tap 

 the head of an ant so as to obtain in response a drop of 

 honey ; evidently the mite carried beneath the ant's head 

 can obtain the boon readily and directly from its bearer, 

 while those mites which cling to an ant's abdomen depend 

 for their supplies of food on other ants, which they touch 

 in the course of their journeys through the nest galleries. 

 It might be imagined that the ants would not carry 

 about and feed these useless guests unless some feeling of 

 satisfaction were to result from the act, comparable, for 

 example, to the gratification many human creatures seem to 

 derive from carrying about and feeding useless small dogs 

 and kittens. But these mite-harbouring ants have really 

 no goodwill towards their tiny guests, for when a mite first 

 attaches itself the ant- carrier tries to shake it off, and the 

 act of feeding in response to the tap of the little creature's 

 foot, is a simple and inevitable reflex, 



