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tions lead enemies to believe that they possess a sting. The striking eye-spots of many insects are believed by some entomologists to be of the nature of terrifying appearances. The larva (Fig. 224) of the Puss moth (Cerura) has been often referred to as a striking example of terrifying appearances. When one of these larvæ is disturbed, “it retracts
its head into the first body ring inflating the margin, which is of a bright red color. There are two in
tensely black spots on this margin in the appropriate position for eyes, and the whole appearance is that of a large flat face extending to the outer edge of the red margin. The effect is an in
tensely exaggerated cariFig. 224.–Larva of the Puss moth (Cerura).
cature of a vertebrate Upper figure shows the larva as it appears face, which is probably when undisturbed ; lower figure, when dis- alonmince to the vorte. turbed.--After POULTON.
alarming to the verte
brate enemies of the caterpillar. ... The effect is also greatly strengthened by two pink whips which are swiftly protruded from the prongs of the fork in which the body terminates. ... The end of the body is at the same time curved forward over the back, so that the pink filaments are brandished above the head.”
284. Alluring coloration.—A few animals show what are called alluring colors—that is, they display a color pattern so arranged as to resemble or mimic a flower or other lure, and thus to entice to them other animals, their natural prey. This is a special kind of aggressive resemblance. A species
of predatory insect called a “praying-horse” (allied to the genus Mantis), found in India, has the shape and color of an orchid. Small insects are attracted and fall a prey to it. Certain Brazilian fly-catching birds have a brilliantly colored crest which can be displayed in the shape of a flower-cup. The insects attracted by the apparent flower furnish the flycatcher with food. An Asiatic lizard is wholly colored like the sand upon which it lives except for a peculiar red fold of skin at each angle of the mouth. This fold is arranged in flower-like shape, “exactly resembling a little red flower which grows in the sand.” Insects attracted by these flowers find out their mistake too late. In the tribe of fishes called the “ anglers” or fishing frogs the front rays of the dorsal fin are prolonged in shape of long, slender filaments, the foremost and longest of which has a flattened and divided extremity like the bait on a hook. The fish conceals itself in the mud or in the cavities of a coral reef and waves the filaments back and forth. Small fish are attracted by the lure, mistaking it for worms writhing about in the water or among the weeds. As they approach they are ingulfed in the mouth of the angler, which in some of the species is of enormous size. One of these species is known to fishermen as the “all-mouth.” These fishes (Lophius piscatorius), which live in the mud, are colored like mud or clay. Other forms of anglers, living among coral reefs, are brown and red (Antennarius), their coloration imitating in minutest detail the markings and outgrowths on the reef itself, the lure itself imitating a worm of the reef. In a certain group of deep-sea anglers, the seadevils (Ceratiidæ), certain species show a still further specialization of the curious fishing-rod. In one species (Corynolophus reinhardti) (Fig. 156), living off the coast of Greenland at a depth of upward of a mile, the fishing-rod or first dorsal spine has a luminous bulb at its tip around which are fleshy, worm-like streamers. At the abyssal depths of a mile, more or less, frequented by these sea
devils there is no light, the inky darkness being absolute. This shining lure is therefore a most effective means of securing food.
285. Mimicry.—Although the word mimicry could often have been used aptly in the foregoing account of protective resemblances, it has been reserved for use in connection with a certain specific group of cases. It has been reserved to be applied exclusively to those rather numerous instances where an otherwise defenseless animal, one without poisonfangs or sting, and without an ill-tasting substance in its body, mimics some other specially defended or inedible animal sufficiently to be mistaken for it and so to escape attack. Such cases of protective resemblance are called true mimicry, and they are especially to be observed among insects.
In Fig. 225 are pictured three familiar American butterflies. One of these, the Monarch butterfly (Anosia plexippus), is perhaps the most abundant and widespread butterfly of our country. It is a fact well known to entomologists that the Monarch is distasteful to birds and is let alone by them. It is a conspicuous butterfly, being large and chiefly of a red-brown color. The Viceroy butterfly (Basilarchia archippus), also red-brown and much like the Monarch, is not, as its appearance would seem to indicate, a very near relative of the Monarch, belonging to the same genus, but on the contrary it belongs to the same genus with the third butterfly figured, the black and white Basilarchia. All the butterflies of the genus Basilarchia are black and white except this species, the Viceroy, and one other. The Viceroy is not distasteful to birds; it is edible, but it mimics the inedible Monarch so closely that the deception is not detected by the birds, and so it is not molested.
In the tropics there have been discovered numerous similar instances of mimicry by edible butterflies of inedible kinds. The members of two great families of butterflies (Danaidæ and Heliconidæ) are distasteful to birds, and are
Fig. 225.—The mimicking of the inedible Monarch butterfly by the edible Viceroy.
Upper figure is the Monarch (Anosia plexippus); middle figure is the Viceroy (Basilarchia archippus); lowest figure is another member of the same genus (Basilarchia), to show the usual color pattern of the species of the genus.
mimicked by members of the other butterfly families (especially the Pieridæ), to which family our common white cabbage-butterfly belongs, and by the swallow-tails (Papilionidæ).
The bees and wasps are protected by their stings. They are usually conspicuous, being banded with yellow and black. They are mimicked by numerous other insects, especially moths and flies, two defenseless kinds of insects. This mimicking of bees and wasps by flies is very common, and can be observed readily at any flowering shrub. The flowerflies (Syrphidæ), which, with the bees, visit flowers, can be distinguished from the bees only by sharp observing. When these bees and flies can be caught and examined in hand, it will be found that the flies have but two wings while the bees have four.
A remarkable and interesting case of mimicry among insects of different orders is that of certain South American tree-hoppers (of the family Membracidæ, of the order Hemiptera), which mimic the famous leaf-cutting ant (Sauba) of the Amazons (Fig. 226). These ants have the curious habit of cutting off, with their sharp jaws, bits of
green leaves and carrying them to their nests. In carrying the bits of leaves the ants hold them vertically above their
heads. The leaf-hoppers 32
mimic the ants and their Fig. 226. — Tree-hopper (Membracidæ), which burdens with remarka
mimics the leaf-cutting ant (Sauda) of Bra- ble exactitude by having zil. (Upper right-hand insect is the treehopper.)
the back of the body ele
vated in the form of a thin, jagged-edged ridge no thicker than a leaf. This part of the body is green like the leaves, while the under part of the body and the legs are brown like the ants.
Some examples of mimicry among other animals than