SECRETARY'S REPORT. 143 



ing* upon them. In fact, the autlior previously alluded to, 

 considers them " the very corn " sown for the use of other 

 insects. "We, however, prefer to compare them to herds of 

 cattle, inasmuch as on the other hand they are protected and 

 cherished by the ants, who are repaid by the honey-like excre- 

 tions of the aphis, yielded at the lightest touch from two small 

 tubes near the extremity of the body. In turning over a stone 

 in the field, who has not seen the busy and anxious ants remov- 

 ing, with the utmost care, not only their own defenceless young 

 to a place of safety, but also showing an equal regard and 

 solicitude for the little whitish oval plant-louse, whose six 

 minute feet are barely able to support her, and totally unfitted 

 for running away. Tenderly picking her up in their mandibles, 

 her sturdy guardians make off at a rapid rate, and after all are 

 in safety, and the bustle caused by the sudden unroofing of 

 their residence has subsided, the little aphis is reassured by the 

 gentle caresses of her protectors, and gives down her honeyed 

 milk to their skilful manipulations. The species infesting the 

 roots of tlie apple is called Pemphig-us pyri; a very similar 

 species which lives upon the roots of several annual plants, has 

 received the name radicis ; these and some other species living 

 beneath the surface of the ground are almost invariably accom- 

 panied by ants in the manner referred to, and inasmuch as the 

 laws of warfare class all who are not avowed friends or neutrals 

 as enemies, we need not hesitate to deluge the little cattle and 

 their keepers with strong soapsuds or lye, and by whelming the 

 whole in one common ruin, save our trees a large unnecessary 

 expenditure of sap. Two or three other species of this same 

 tribe are found in immense numbers drawing their subsistence 

 at the other end of the -line. On the young shoots and small 

 green leaves of the apple-tree, are found the Aphis mali, of 

 Fabricius ; the tender shoots and flowers of the cherry are fre- 

 quently swarming with the Aphis cerasi of Fabricius. Those of 

 the plum, the peaches, and other fruit trees, are often attacked 

 in the same manner by other species. The aphis of the apple is 

 quite dark-colored, with a greenish abdomen ; that of the cherry 

 almost or entirely black. Others, as the aphis of the rose, are 

 of a pure green color. The aphides of the leaves and twigs are 

 attended, like their brethren of the roots by an escort, or rather 

 guard of ants. Tiiese cannot pitch their tents like the keepers 



