[Ill.u.s.tration]

A GREEN-HEADED HORSE FLY

(_Taba.n.u.s punctifer_, O. S.)

There are nearly two hundred species of horse flies in North America, and this creature represents one of the commonest forms. It doubtless hatched out somewhere on the edge of the brook which flows through my place in Maryland, and its larval self fed upon other insect larvae or on the snails and slugs it found itself among.

The bands of iridescent green and copper and purple across its enormous eyes made it a beautiful creature to look upon.

We never used to think the bite of flies was anything worse than annoying, but recently, since we have discovered the danger of letting the germs of disease into the blood streams of our bodies, we have come to see the ghastly possibilities which lie in the piercing mouthparts of these flies.

They suck the blood of animals whose blood streams may be swarming with disease germs, and then fly directly to our houses and puncture our skins with a beak covered with these germs which slip off into our veins.

Until we know that the diseases of the birds, and field mice, the c.o.o.ns and 'possums, and all other warm-blooded beasts of a locality are harmless to us, or that it is impossible to transmit them to human beings, it is best to look upon these blood-sucking creatures as winged hypodermic syringes laden with disease.

It has been suggested that the horse flies carry anthrax, and their bites sometimes cause malignant pustules. They are also under suspicion as carriers of infantile paralysis.

FEATHERED INSECTS

(_Lepidoptera_)

These are peculiarly the feathered fliers of the insect world, for their wings and their bodies, too, are covered with most remarkable one-celled feathers or scales of gorgeous colors which make of some of them the most brilliant of all living things.

Just what these scales are for is not entirely clear, and will not be, perhaps, until we understand the purpose of the gorgeous coloring itself.

There is a theory that these scales help to grip the air in flying.

It is a curious coincidence that one of these gorgeously colored creatures should furnish mankind with the material for his own most gaily colored raiment. The silkworm is one of the very few domesticated insects, so to speak, of all the hundreds of thousands of insect species in existence, and a hundred millions of dollars is paid every year for the delicate silk threads unraveled from countless millions of coc.o.o.ns which the silkworm larvae have laboriously fashioned around themselves.

To many people, moths are known by what they leave behind--holes in the winter woolens; and b.u.t.terflies are to them, somehow, things of the sunlight and the summertime. It is worth while to know that these great families of b.u.t.terflies and moths are not by any means divided equally, that for every family of b.u.t.terflies there are at least nine of the moths and that the b.u.t.terflies form but a small proportion of the gaily colored insects of the fields.

Perhaps it makes but little difference to the public, who call them all alike, but it is as easy to tell a b.u.t.terfly from a moth as it is to tell a lizard from a snake, for all the b.u.t.terflies have club-shaped feelers, or antennae, whereas the moths do not, and any child of six can learn to tell the two apart.

No b.u.t.terfly or moth in its winged state can harm us or our plants. It has no jaws, but keeps itself alive by sucking nectar from the flowers or juices from the fruits or other parts. Its other self, its larva, however, can cause no end of damage. One inconspicuous, brownish form, the codling-moth, no larger than my thumb nail, costs apple growers about ten million dollars every year, while the cabbage moth, the clothes moth, the cutworm and the dreaded gipsy-moth are only a few examples of a gigantic army of voracious larvae against which man has been struggling ever since he first began to plant seeds in the ground or set out trees for fruit.

[Ill.u.s.tration]

LARVA OF THE SWALLOW-TAIL b.u.t.tERFLY OF THE SPICE-BUSH

(_Papilio troilus_, Linn.)

Is this, I wonder, an insect make-believe, a caterpillar mask, as it were, to frighten away enemies? The black and white eye-spots are not real eyes, but to a bird they doubtless seem so. Its real eyes are inconspicuous points at each side of the head, too small to appear in the photograph.

Few of as stop to think, as the beautiful swallow-tail b.u.t.terfly, gorgeous in its black and yellow painted wings, flits by us, that it is made of sa.s.safras and spice-bush leaves gathered together and ground up. This monster is a leaf-eating creature, its purpose being the acc.u.mulation of food material out of which is made inside of it the gorgeous swallow-tail b.u.t.terfly. It feeds on sa.s.safras and spice-bush leaves, and when the time arrives makes a nest for itself by fastening the edges of a leaf together.

In this nest it pa.s.ses the winter. When spring comes it breaks open the gray sh.e.l.l of the chrysalis, unfolds a pair of black and gold wings with long tails to them, and flies away in the sunshine in search of flowers and a mate. It is then no more like this monster than an eagle is like a hippopotamus, yet after it has flown about, sucking nectar through its long beak, it mates and lays a ma.s.s of eggs, out of which hatch again these strange, weird beings.

[Ill.u.s.tration]

FORE PART OF A BROWN b.u.t.tERFLY

(_Agrynnis cybele_, Fab.)

It is hard to realize that this is the portrait of the head and fore part of a beautiful brown b.u.t.terfly.

Its head is almost all taken up with the gigantic eyes, which are composed of thousands of tiny facets. The long, trunklike mouth with which it sucks the nectar from the flowers is coiled up like a watch spring. Like shingles on a roof, the scales are fastened in tiers over the broad surface of the wings stretched over the stiff ribs or framework.

The white spots are made by hundreds of white scales and the brown blotches by brown scales, and what these scales are for n.o.body seems to know. Perhaps they help to grip the wind, for they have running lengthwise of them deep and parallel corrugations so small and fine that were a single scale as large as a lady's opened fan these corrugations would represent its sticks.

The caterpillar from which this splendid creature came is black, with branching spines, and feeds at night on violets and other plants.

The graceful beauty of the b.u.t.terfly, its seemingly happy existence, its life among the flowers, where it sips the nectar that the flowers provide, are all a part of common knowledge.

The real life of the b.u.t.terfly, however, is not so pleasant as we think.

Have you ever found a b.u.t.terfly hanging beneath a leaf on a cold summer morning drenched with dew and stiff with cold? Have you ever seen one trying to cross a field in a rain-storm and observed it vainly attempting to navigate the conflicting air currents? Where do they roost at night and on rainy days? Where do they come from and what becomes of them? These are matters which it has often taken men years to find out, and even now there are many thousands of species of b.u.t.terflies which are known only by a preserved specimen caught in its flight by the net of some collector.

[Ill.u.s.tration]

YELLOW b.u.t.tERFLY

(_Colias philodice_, Gdt.)

The Doctor Jekyll and Mr. Hyde is so complete between the b.u.t.terfly which flits over the cabbage patch and the velvety green worm that eats holes in the leaves of the cabbages that it is no wonder that for centuries no connection between the two careers of these creatures, seemingly so far apart, was suspected. In general it is true that no moth or b.u.t.terfly is injurious to plants except in its larval stage, and herein has lain the clever deception which has doubtless protected these gay mating creatures of the air from the systematic attacks of man until quite recent times.

This picture shows what every boy and girl should know, that every b.u.t.terfly has club-shaped feelers or antennae.

It is said of certain species of yellow b.u.t.terflies that the males give off a pleasing, aromatic odor which is exhaled from the front wings through hundreds of minute, slender scales--scales quite different from those with which the wings and body are covered. This scent, which is so strong that it can be detected by even our blunted olfactory organs if we rub the wings between thumb and forefinger, is supposed to attract the females in some way that is little understood. As among these particular b.u.t.terflies the male seeks out its mate, it is difficult to understand why it should be the male which has the perfume, since it does not serve to tell the female where her mate is to be found. The inference is that in some way the perfume charms the female.

In some species it is the females which give off an odor, and in either case the distances over which these odors extend and are detected by the males or females respectively are a.n.a.logous to the inconceivable reach of wireless telegraphy. And who knows but the mechanism of these creatures is set to respond to the swiftly traveling ions which make wireless telegraphy possible?

[Ill.u.s.tration]

A BABY OF THE SKIPPER b.u.t.tERFLY

(_Eudamus t.i.tyrus_, Fab.)

There is something fascinatingly strange to me in the babies of the winged b.u.t.terflies, and I wonder why so many people have an aversion for them?

Can there be an instinctive fear of anything that crawls, or is not this fear taught us by unthinking persons? The child is not afraid of the wide-mouthed naked little birds in the nest, or the little blind pink mice, and certainly they are no more innocent looking than the brilliant colored larva of the b.u.t.terflies or moths.

What helpless things these babies are! They cannot fly, they cannot fight, they can barely see, and even their gait is a hobbled one.

Their business is to eat, and their jaws must keep busy pretty constantly to fill their stomachs with leaf fragments, for the greater part of the soft, flabby bodies is stomach. They are males and females but which they are you cannot tell until they turn into b.u.t.terflies.

Along this creature's sides, like portholes in an ocean liner, are the breathing pores, nine in number. Most animals which live on land take air in through a single opening into a great cavity through which the blood circulates and is purified, but the caterpillars, and all insects in fact, instead of circulating their blood in and out of a pair of lungs, have, running through their bodies, a labyrinth of air pa.s.sages, all connected with the outside air by means of breathing pores.

This caterpillar's eyes are poor affairs, and unless you look closely you will not find them, for they are merely a few raised spots, like blisters, beneath the skin on either side of its jaws.