Nearly every person who grows an apple tree, has observed that the branches of the older, and stems of the younger trees, are frequently covered with a minute scale, showing in general no appearance of life, and resembling nothing so much as a miniature oyster shell This little scale is, however, an insect, and one of the many enemies of the apple, belonging to a family that contains more anomalous forms than any other. It is the Homoptera of Maclay. All this family are supplied with a suctorial mouth arising so far back on the under side of the head as apparently to come from the breast in some species. The present insect is included in the genus Coccus, and has for its near relations, some that have been useful to man from the time of the ancients, producing valuable dyes, the cochineal being one of them; and it is calculated that in one pound of this dye there are 70,000 of these little insects. It feeds upon the cactus.

Our Apple Scale has, however, no qualities to render it useful; and a short account of its life and habits will be all that is necessary. When first hatched from the egg it possesses considerable ambulatory powers, and can crawl all over a tree and select a situation. It then inserts its rostrum into the tender bark and draws the sap, and such a constant drain, by the countless numbers found upon a tree, must be very injurious. The insect remains in this position until death in the female, undergoing its transformations, which, instead of producing a higher state of development, as in most other forms, has a contrary effect, it becoming in fact, a mere inert, fleshy mass, in some allied species losing even the rudiments of limbs and all appearance of articulation. The male, on the contrary, however, who is much smaller, in casting off his pupa skin, obtains pretty large wings, and well developed limbs, armed with a single claw, and his mouth becomes obsolete; he then sallies forth in search of his partner, of which he sees nothing but the pupa envelope. The female afterwards becomes distended with eggs.

She then gradually dries up leaving the shell of her body for a covering to the newly hatched young, of which there are two broods in a year.