68 DOMESTIC ANIMALS OF ANTS. 
more than a hundred years ago by the Abbé Boisier 
de Sauvages.! 
Nor are the aphides the only insects which serve as 
cows to the ants. Various species of Coccide, 
Cercopis, Centrotus, Membracis, &c., are utilised in the 
same manner. H. Edwards? and M’Cook * have observed 
ants licking the larva of a butterfly, Lycena pseudar- 
giolus. 
The different species of ants utilise different species 
of aphis. The common brown garden ant (Lasius 
niger) devotes itself principally to aphides which 
frequent twigs and leaves; Lasius brunneus, to the 
aphides which live on the bark of trees; while the 
little yellow ant (Lasius flavus) keeps flocks and herds 
of the root-feeding aphides. 
In fact, to this difference of habit the difference of 
colour is perhaps due. The Baltic amber contains 
among the remains of many other insects a species of 
ant intermediate between our small brown garden ants 
and the little yellow meadow ants. This is possibly 
the stock from which these and other allied species are 
descended. One is tempted to suggest that the brown 
species which live so much in the open air, and climb 
up trees and bushes, have retained and even deepened 
their dark colour; while others, such as Lasius flavus, 
1 Observations sur Vorigine du miel, par YAbbé Boisier de 
Sauvages, Jowr. de Physique, vol. i. p. 187. 
2 Canadian Entomclogist, January 1878. 
8 The Mound-making Ants of the Alleghenies, p. 289. 
