For ants that keep and rear Aphides in their nests we need not go farther than our own little yellow one—_Lasius flavus_. They guard and look after the eggs of their protégés, which form little black shiny clusters, with the same care that they bestow on their own, and when they are hatched set about providing food for the young aphides. This, it would appear, does not consist of the roots of various plants penetrating the nest itself, for Sir John Lubbock found that the first business of the ants, after the young aphides had appeared, was to conduct or carry them out of the nest, evidently in order that they should find their natural food. None being at hand under these artificial conditions, and the plants required not being known, the poor aphides all died, and this happened again the following year. In the year succeeding to this, however, Sir John was more fortunate, and this is the account he gives of his interesting discovery: “The eggs commenced to hatch the first week in March. Near one of my nests of _Lasius flavus_, in which I had placed some of the eggs in question, was a glass containing living specimens of several species of plants commonly found on or around ants’ nests. To this some of the aphides were brought by the ants. Shortly afterwards I observed on a plant of daisy, in the axils of the leaves, some small aphides very much resembling those from my nest, though we had not actually traced them continuously. They seemed thriving, and remained stationary on the daisy. Moreover, whether they had sprung from the black eggs or not, the ants evidently valued them, for they built up a wall of earth round and over them. So things remained throughout the summer, but on the 9th of October I found that the aphides had laid some eggs exactly resembling those found in the ants’ nests; and on examining daisy-plants from outside I found on many of them similar aphides and more or less of the same eggs.”[49]