The members of this tribe are well characterized by their name, for most of them show on the upper wing surface tones of coppery brown, more or less marked around the margin with darker shades. On the under side of the tarsi there are numerous spines in irregular clusters. In the chrysalis there are curious hair-like projections on the skin, which are short and shaped like tiny toadstools or mushrooms.
While some of the Coppers are very abundant, the majority are rather rare. Only a few species are sufficiently widely distributed to require description here.
The Wanderer
Feniseca tarquinius
In many orders of insects there are whole families whose larvae are habitually carnivorous, feeding entirely upon other kinds of insects. This is especially so in case of the beetles, the flies, the true bugs, and the great order to which the bees and wasps belong. Among the scale-winged insects, however, carnivorous caterpillars are rare, seldom occurring among the moths and in hardly more than one species among the butterflies. This one exception is the modest-looking little butterfly fancifully called the Wanderer, perhaps because instead of frequenting the flowery fields where other butterflies congregate it wanders in and out among the alders by brooks and ponds, alighting oftener upon a leaf or twig than upon a flower—the latter apparently lacking for it the attraction it has for other butterflies.
If you watch one of these copper-hued creatures for awhile, however, you will soon see that its wandering is not aimless but has rather a method all its own. Perhaps you will see it alight upon an alder twig on or above which you are likely to notice curious woolly white excrescences. If you are close enough you will probably see the butterfly uncoil its tongue and sip up a liquid on twig or leaf—the exudations of the woolly aphids that make up the supposed excrescence and suck the sap from the bark. Much of this sap passes through the bodies of the aphids and collects in liquid globules on twigs and leaves, forming a sort of honey-dew which is much sought after by flies, wasps, and other insects. It seems to form the chief sustenance of these Wanderers.
But many of these butterflies have another purpose besides that of sipping the honey-dew. Should you watch one of the mother butterflies carefully you would be likely to see her alight on or near a colony of woolly aphids and run rather rapidly over them in a wasp-like manner, finally stopping long enough to lay a tiny, roundish, slightly flattened egg upon the twig, generally on the under side, and only one in a place. Then she may continue her way, wandering lazily along the alder-bordered stream.
Let us now centre our interest upon the egg. Three or four days later it hatches into a curious caterpillar. Instead of having mouth parts fitted for biting leaves as is the case with most butterfly larvae, it has one fitted for grasping, piercing, and sucking the juices of the plump bodies of the aphids, which it finds hard by its place of birth. It also has silk spinnerets connected with its mouth, so it is able to spin a web to shelter it from being run over by its intended victims.
The newly hatched larva is not slow to take advantage of the facilities with which it is provided. It at once begins to spin a web above and around itself, from the end of which it reaches out for the nearest aphids, sucking their life-blood and casting their empty skins to the discard of its protecting web. The skins thus serve as an additional shelter so that, as the caterpillar moves forward, increasing the number of its victims from day to day, it extends its web and the protection of the cast skins intermingled with it, while through all—the cast skins, the silken web, and even the hairs on the body of the caterpillar—there runs a woof of the woolly excretion—effectually concealing the larva from sight.
The woolly aphids thus serve as the sole food of the caterpillar during its brief life as a larva. Perhaps because of the pre-digested nature of its food, it is able to mature much sooner than most butterfly larvae. In about eleven days after hatching it is ready to change to a chrysalis, having undergone during this period only three moults, instead of at least four as with other caterpillars. Each caterpillar then changes to a chrysalis which is remarkable because the form and color of its back bears a striking resemblance to the face of a miniature monkey. It remains in this condition nearly a fortnight and then emerges as a butterfly.