The principal insects which are thus used, are the plant-louse, and the gall-insect.
Although the honeydew does not come from the little tubes on the back of the plant-louse, yet those tubes have their uses.
On one of these leaves he placed a plant-louse, which was born under his own eyes, of a wingless mother.
On the 4th of August, about one o'clock in the afternoon, I put into solitary confinement a plant-louse of the third generation.
The plant-louse or aphis is a sap-sucking insect which feeds and multiplies rapidly often seriously injuring crops.
The Red Ant (Formica rufa) is singularly adroit in seizing the droplet left it by the plant-louse.
Perhaps the first battle will have to be fought with the aphis, or plant-louse.
When they have got possession of a plant-louse, they excite it to secrete this liquid, but without doing it any harm.