416 INTRODUCTION TO ZOOLOGY CHAP. 



Ants react to some stimuli much as higher animals 

 do. They are made bold by success, and sometimes are so 

 demoralised by failure that a pugnacious colony will turn 

 arrant coward, and flee before a handful of much weaker ants. 

 Also in their apparent devotion to the welfare of the nest 

 they vary considerably, and all these points tend to show 

 a plasticity which is usual where intelligence is at work. 



Other In- Besides keeping in their nests flocks of 

 mates of the Aphides, which supply food for the colonies, ants 



Nest - tolerate, and even in some cases seem to welcome 

 in their nest, other very varied inmates. 



In the nest of Lasius flavus we find two kinds of little 

 white creatures that wander about, tolerated or unnoticed by 

 the ants ; these are : 



(1) A little white wood-louse with very short antennae 

 and a very long name ! Platyarthrus hoffmannseggi, which 

 strolls slowly about the nest, ignoring the ants and their 

 larvae, feeding probably on the refuse of the nest, and so 

 acting as a scavenger (see Fig. 107). 



(2) Another tiny, white, blind form, a wingless insect 

 allied to the " springtails " (Podura) and known as BecUa. 

 This also is ignored by the ants, but seems to be really of 

 use to the colony in scavenging. These are often present 

 in numbers in the nests, running actively about. 



Then also Lasius flavus allows in its nest, and indeed 

 treats with great favour, a yellowish-coloured, small, blind 

 beetle (Claviger testaceus), characterised by its 

 small wings and club-shaped antennae of 

 very few joints. On the body of this beetle 

 are yellow hairs which secrete some volatile 

 substance much loved by the ants, who are 

 constantly to be seen licking it off". Wasmann 



FIG. 314. suggests, from the fascination this substance 

 Claviger testaceus. hag for the ^ ^^ ^ must affect them 



*' Yell J s ecreting much as a good cigar affects a smoker ! It is, 

 however, rather a dangerous fascination for 

 the ants, for the beetle, though fed regularly by its hosts 

 with regurgitated food, nevertheless is said often to eat the 

 ant larvae. In spite of this the ants cherish the assassins, 

 feeding them, often carrying them about in their jaws, and 

 even allowing them to ride on their backs ! 



