I 82 HYMENOPTERA CHAP. 



of ;i nutritious kind. The Insects we have spoken of are, how- 

 ever, rather of the nature of ant-cattle, and the fondness of the 

 ants for them is not very remarkable. The relations of the ants 

 to the peculiar species of Insects that live only in or around their 

 nests are much more extraordinary. The greater number of these 

 guests belong to the Order Coleoptera, and of these there are many 

 hundreds probably many thousands of species that depend on 

 ants for their existence. The family Pselaphidae furnishes a 

 large number of ants'-nest beetles, and it appears probable that 

 most of them excrete some 

 sugary substance of which the 

 ants are fond. Many of these 

 Pselaphidae are of the most 

 fantastic shapes, more especi- 

 ally the members of the sub- 

 family Clavigerides. But the 



,, , , FIG. 82. The beetle, A temeles, soliciting 



most curious of all the ants- food from an ant. (After Wasmann.) 



nest beetles are the Paussidae, 



a family exclusively dependent on ants, and having the curious 

 faculty, when disturbed, of bombarding that is, of discharging 

 a small quantity of vapour or liquid in a state of minute 

 subdivision accompanied by a detonation. Many species of 

 Staphylinidae are peculiar to ant's-nests, and most of them are 

 indifferent or inimical to their hosts, but some of them, such as 

 Atemeles (Fig. 82) and Lomechusa, are doubtless producers of sweet 

 stuff that is liked by the ants. The ants feed some of their special 

 favourites amongst these guests in the same manner as they feed 

 one another, viz. by opening the mouth, causing a drop of liquid 

 to appear on the lip, and remaining passive while the guest 

 partakes of the proffered bonne boucJie. This way of giving food 

 to other individuals is a most remarkable feature in the character 

 of ants; it is not the same system that they adopt in feeding the 

 larvae, for they then make a series of actual movements, and 

 force the nutriment into the mouths of the grubs. Besides the 

 Insects we have mentioned there are also Orthoptera, Hemiptera, 

 Poduridae and Thysanura,, Acari, and small Isopod crustaceans 

 that live exclusively in company with ants. We have mentioned 

 that a few Hymenopterous and Dipterous parasites have been 

 detected living at the expense of ants ; it is probable that 

 closer observation of the ant larvae and pupae in their nests 



