298 ENTOMOLOGY 



aid of a hand-lens, one may see the ants hastening about among the 

 plant lice and patting them nervously with the antennae until at length 

 some aphid responds by emitting from the end of the abdomen a glisten- 

 ing drop of watery fluid, which the ant snatches. This fluid, contrary 

 to prevalent accounts, is not furnished by the so-called honey- tubes of 

 the aphid, but comes from the alimentary canal; the " honey- tubes " are 

 glandular indeed, but are probably repellent in function. In some 

 instances ants give much care to their aphids, for example. covering them 

 with sheds of mud, which are reached through covered passageways. 

 More than this, however, some ants actually collect aphid eggs and pre- 

 serve them over winter as carefully as they do their own eggs. In one 

 such instance Lubbock found that the aphids upon hatching, after six 

 months, were brought out by the ants and placed upon young shoots of 

 the English daisy, their proper food plant. In our own country, as 

 Forbes has discovered, the eggs of the corn root louse (Aphis maidira- 

 dicis) are collected in autumn by ants (especially of the genus Lasius) 

 and stored in the underground nests. In winter the eggs are taken to 

 the deepest parts of the nest, and on bright spring days they are brought 

 up and even scattered about temporarily in the sunshine; while if a nest 

 is opened, the ants carry off the aphid eggs as they would their own. 

 In spring the ants tunnel to the roots of pigeon grass and smar tweed, 

 seize the aphids and carry them to these roots, and later to the roots of 

 Indian corn. Throughout the year the ants exercise supervision over 

 these aphids; occasionally, as Forbes says, an ant seizes a winged louse 

 in the field and carries it down out of sight, and in one such instance it 

 appeared that the wings had been gnawed away near the body, as if to 

 prevent the escape of the louse. Similar relations exist also between 

 ants and some species of scale insects. 



Guests. Though Aphididae and Coccidae are able almost always to 

 live without the help of ants, there are some insects which have never 

 been found outside the nests of ants. Most of these insect guests are 

 beetles, notably Staphylinidae and Pselaphidae. The rove-beetles make 

 themselves useful by devouring refuse organic matter, and these scav- 

 engers are unmolested by the ants with which they live. A few myrme- 

 cophilous beetles furnish their hosts with a much-coveted secretion and 

 receive every attention from the ants, which clean these valuable beetles 

 and even feed them mouth to mouth, as the ants feed one another. 

 Lomechusa (Fig. 293) is one of these favored guests, as it has abdominal 

 tufts of hairs from which the ants secure a secreted fluid. Atemeles 

 (Fig. 294) is another; it solicits and obtains food from the mouth of a 



