CHARACTERS, LIFE-HISTORY, AND METAMORPHOSES OF THE COCCIDIDÆ.
The first principal character separating the Coccididæ from the rest of the Homoptera, and distinguishable without microscopic examination, is the absence of wings in the females at all stages of their existence.
The second principal character is the absence of any apparatus for feeding and digesting in the males.
From these two characters it follows that the females can only extend their operations by, at the best, crawling from plant to plant, or by being carried about by birds or other agency; also that the males cannot enjoy more than a very short existence, their work being entirely confined to impregnating the females. Hence, in any endeavours to destroy these insects, the males may be disregarded, and the females only attended to.
Other distinguishing characters, chiefly microscopic, are—
1. The presence of only one joint in the tarsus or fourth joint of the leg, in both males and females ([Plate I.], Figs. 6 and 7, ta);
2. The presence of only a single claw terminating the leg in both males and females ([Plate I.], Figs. 6 and 7);
3. The presence of only two wings, with two halteres, in the full-grown males ([Plate XXI.]);