purchasi.

II. The Male Insect.

It has been remarked above that, as the full-grown males of the Coccididæ are destitute of any organs for feeding whatsoever, there is no reason for making systematic attacks on them for economical purposes. Their function is simply to impregnate the females, and their life at this stage must necessarily be very brief. It will suffice in this place to observe that in all cases these males are small, two-winged flies, their size varying from about ¹/₄₀ in. to ¹/₄ in. in length; colour usually yellow or red; wings longer than the body, hyaline (glassy) and often iridescent, and, in repose, lying flat, partly crossing each other. The antennæ are long, slender, and hairy, consisting of nine or ten joints. The legs are also slender and hairy, the tarsus having only one joint, and terminating in a single claw. The insects are generally very active. Types of antenna, foot, wing and haltere, and a diagram of the arrangement of the eyes and ocelli, are given in Plate I., Figs. 7, 12, 13, 14, 15, 17.

The males are thus so small and rapid in their movements that it is difficult in most cases to find them in a free state. The usual way to procure them is by hatching them from the pupæ. In their course of life they pass through four stages, as do the females—viz.: 1, the egg; 2, the larva; 3, the pupa; 4, the full-grown insect.

1. The egg is, as far as can be made out, precisely the same as that of the female, though Dr. Signoret believes that in one or two species there may perhaps be minute differences.

2. The larva is, as stated above, similar to that of the female.

3. The pupa. Here the first distinctions between the sexes may be noted, and these are principally observable in the cocoons or puparia, rather than in the insect itself—at least to outward appearance. The male pupa is, in all cases—even in those where the female pupa is naked—enclosed in some kind of covering. In the Diaspidinæ the puparium is formed partly of fibrous secretion and partly of discarded skin; only, as the full-grown male emerges from it as a fly, and does not remain on the plant, there can be only one such skin—that of the larva; consequently it is easy to distinguish the male puparia from the shields of the adult females by the presence of only one discarded pellicle instead of two. In the Lecanidinæ and the Coccidinæ the male puparia are distinguishable usually by a narrower and more cylindrical form than those of the females, where these latter are covered; in the naked species the males are generally in white waxy or cottony cocoons.

Examination of the pupæ in these coverings will generally show more or less developed processes on the back and sides, which are so evidently the rudiments of the future wings that the presence of a male is not doubtful. In other respects the male pupæ are not always to be distinguished from the females.

3. The full-grown male has been described above. It is usually easy to procure specimens, provided the pupæ are obtained. If any of these, in their coverings, are put into pillboxes with glass tops, or any place where light reaches them, they will generally produce the full-grown insect sometimes in a few days, sometimes after several weeks. The time of year for this seems very variable. Males emerge from the puparia apparently indifferently (in New Zealand) in summer or winter.

CHAPTER III.

PRODUCTS OF THE COCCIDIDÆ.

[Waxy or cottony matter: the "honeydew" and the black fungus—"smut" or "black blight"—growing upon it.]

The Coccididæ, in some parts of the world, excrete various substances which are of commercial value, as, for example, shellac, "manna," candle-wax, &c. Cochineal is not in the same category, as it appears to be a colouring-matter pervading every cell of the tissues of the insect from which it is extracted—Coccus cacti. But there is no need to dwell here upon the ordinary excretions of the New Zealand insects, as they appear to be not sufficient either in quantity or quality for any practical service. The fibrous puparia of the Diaspidinæ appear to be quite useless. The tests of the Lecanodiaspidæ, such as Ctenochiton perforatus, Inglisia ornata, &c., although more or less waxy (but of very brittle material, often more like glass) are much too insignificant to repay any trouble taken to collect them. Of all the family, Cælostoma zælandicum, in its second stage, seems to produce the greatest amount of material, its large, hard, waxy tests being very thick and solid, and often clustered in hundreds on a root or a twig of Muhlenbeckia; but, supposing this substance (of which the true chemical nature[D] is not yet known) to be fit for some purpose, there does not seem to be any means of cultivating the insect to profit. Dactylopius alpinus produces in alcohol a rich red tint, and this not by way of excretion, but from the colouring matters of its tissues, as in the case of Coccus cacti; but here, again, the rarity of the insect and its out-of-the-way habitat would be a bar, even if nowadays it were worth while to cultivate a New Zealand cochineal. At present, therefore, there seems no reason to believe that the Coccididæ of this country are likely to furnish any products of a useful or commercial character.