Chapter II: The Insect World (3)

It is hard to realize, as you watch this swiftly moving dragon of the air, that it has spent the first stage of its life as a slowly crawling, ugly water monster lying in wait among the reeds and grasses for some unsuspecting water bug or larva to pass by.

The female, as she skims the surface of some pool, drops into the water her clumps of dragon eggs, a thousand at a time, and from these are born the ugly water dragons, which, when come of age, grow wings and, crawling to the surface, split their old skins open, unfold and dry their closely packed wings, and dart away into the sunshine to prey upon the other creatures of the air.

THE DRAGON-FLY AND ITS VICTIM

(_Macromia sp._)

Who would suspect, as one of these dragon-flies darts by him on the roadway, that every few minutes its jaws are crunching some helpless insect caught in its flight?

When I caught the dragon-fly whose picture is shown here, I held him by the wings, and, catching a fly that buzzed about the table, dropped it in his claws. Without a moment's hesitation his mouth opened wide and closed upon the fly. I watched it disappear underneath his great upper lip and almost fancied I could hear its shell crack as the powerful jaws and lower lips turned it around and around in the mouth. A few seconds only, and the sucking throat had drawn out all the blood and the lips threw out a ball-like mass made up of the fly's wings, legs and crushed body skeleton. Then it opened again for more.

One entomologist has said that in two hours a dragon-fly will eat at least forty house flies, and Doctor Howard says that if starved for food it will eat up its own body.

No doubt these dragons of the air are to be counted as among our greatest friends, and in places in the East where life is made a burden by that humming, stinging pest, the mosquito, its presence in great numbers helps amazingly in keeping down the day-flying forms of that insect. It has gone into the Hawaiian Islands with the mosquito and has learned there to breed in the water found on the leaves of lilies growing on dry land.

Perhaps someone will find a way to domesticate this creature and make it live upon the house flies around the house. As a first step, Needham has fed the larvæ on bits of meat.

Sharpe, the British authority, has observed a dragon-fly returning again and again to the same bush, and Westwood believes he saw the same individual hawking for several weeks together over the same small pond.

DRAGON-FLY NYMPH MASKED

(_Libellulid_)

As Kellogg says, it must, indeed, be worth more than a week of study in the house to see just once the transformation of one of these mud dragons from the bottom of a pond into a beautiful dragon of the air,--a dragon-fly.

Of all the strange, weird monsters with which I have ever had to deal, this water one seems somehow weirdest. It reminds me of those sandy-colored, deep-sea fishes which, snuggling under the sand of the sea bottom, wait for their prey to come along and then dart out and seize them with their powerful jaws.

The mud dragon has a mask which, for the purpose, is certainly the most effective thing one can imagine. Its victims must be greatly surprised to see the mask drop, revealing a sheep-like nose, mouth, and lips, while the mask itself opening out and splitting down the middle, becomes a pair of needle-margined, powerful claws so strong that even fishes are sometimes caught and held by them.

It is strange to think of this dragon concealing its claws by making a shield of them to cover its ugly face while it waits in ambush for its game.

Its eyes and body are the color of mud and must be very hard to see.

This photograph shows the mask in place, the grinning mouth a long curved slit across the face, while resting on the ground, as one would rest one's elbow on the table, is the powerful claw arm, so strong that you would find it difficult to pull the mask away, or having done so to keep it down.

DRAGON-FLY NYMPH UNMASKED

(_Libellulid_)

Pulled down from the mud dragon's sheep-nosed face, the mask is resting on the ground. It can be stretched out much further and also opened up to form a pair of powerful claws. Along the edge of the mask is a fringe of inward-pointing spines like those which edge the leaf margins of a venus flytrap. The eyes are large and many-faceted and form the blunt-pointed corners of its head.

The under-water battles in which these mud dragons, or dragon-fly nymphs, take part must be something terrible. It is recorded that in Hungary 50,000 young fishes were put into a pond in which enormous numbers of these nymphs occurred and only fifty-four fishes survived. One is not surprised to learn, too, that they will eat each other up.

On the whole, however, it is doubtful if between the flies and other injurious insects which the dragon-flies destroy in the air, and those larvæ of mosquitos which the water nymphs destroy in the ponds, there is any other family of insects toward which man should feel more indebted than toward the family of the odontata or dragon-flies.

AN ABANDONED DRAGON CASE

(_Libellulid_)

From this muddy outworn shell, left to decay at the bottom of a pool, there came, sometime last summer, a gorgeous, four-winged dragon-fly. A little after dawn, what was once this water nymph or mud dragon, tired perhaps of its mud existence, ready anyway for the transformation, crawled up out of the water upon some stone or stick and waited there for its back to split open up and down. It pulled its soft, boneless legs from their cases, now lying along the abandoned shell, its wings closely packed together from the two cases on its back and its head and jaws from out the broken head shell. Even every air passage running through its body shed its parchment lining.

Soft and helpless it crawled away into the grass to wait until its wet, soft outer skeleton should harden and make it possible for the powerful wing muscles to pull against it and for the broad wing films to dry and straighten out. By noon the transformation was doubtless quite complete, and flitting across the pond went the recent inhabitant of this dragon-fly case.

THE DAMSEL FLY

(_Agrion maculatum_, Beauvois)

Most insects' legs are made to walk with, but those of the dragon-fly are not. They are bunched together so near the head that when the creature alights it can do little more than cling to what it lights upon. Instead, the legs, with their spines, form a perfect basket, open towards the front, and thus become the organs with which flies are caught.

This damsel fly, as it is called, is smaller and more delicate than the dragon-fly with quite a different head. It inhabits shrubby woodland and is not often seen. Some of its tropical relatives are creatures of extraordinary fragility and delicacy.

Its wings, which move in perfect unison, although distinct, are operated by such ingenious mechanical devices within the body as to have long ago suggested a flying machine, and it is strange how like a dragon-fly Professor Langley's aerodrome, the first of them all, does look, although of course the aerodrome's wings were rigid.

One realizes what enormous eyes these dragon-flies have when one begins to compare them with the size of the head.

THE LACE-WINGED FLY AND THE APHIS LION

(_Chrysopa sp._)

So fragile and delicate does this creature appear that one can but wonder how it exists in the jungle of the grass. It has a disagreeable odor, it is said, and this is perhaps the reason that it holds its own, for it flies so slowly and is so conspicuous that it would otherwise fall a prey to every insectivorous bird and dragon-fly.

Its other self is the Aphis Lion, a wingless but very active creature which hunts for plant lice and when it finds one punctures it with its mandibles, raises it in the air and lets the blood trickle down into its mouth. It sucks eggs, too, and, shameless creature that it is, it sucks those of its own species, or would, at least, if the mother instinct had not taught the winged females to lay their eggs on the ends of long, slender, stiff stems which the undiscriminating larvæ cannot climb, much as a human mother puts the pot of jam on the top shelf where the children cannot get it.

THE WINGED ANT LION

(_Myrmeleon immaculatus_, De G.)

As with many of these monsters, it is the other self, the larva of the winged ant lion, which is the fascinating study.

This winged form merely lays the egg from which hatches out the soft, spindle-shaped young with jaws like pincers. This little creature at once marks out a tiny circle in some dry, sandy place, and begins to dig a pitfall for its prey, the ants.

By pitching the sand with its broad, flat head, just as a man who digs a well would pitch out shovelfuls of dirt, the young ant lion excavates a tiny crater in the sand and hides itself in the crater's pit with its pincers sticking upwards through the fine, loose sand.

Any child who has jumped into his father's oat bin and tried to climb up the hillside of tumbling grain, knows how hard it is to get out. If he will imagine a hidden monster waiting with jaws opened at the bottom, he will have some sympathy for the unlucky ant which, slipping upon the rolling sand of the ant lion's crater slides slowly towards its pit--helped perhaps by dirt thrown on it by the ant lion.

There seems to be no escape, and once within reach, the pincers close on it, and along their grooved inner faces, helped down by special tongue-like licking organs, the blood trickles and is guided to the mouth and thence into the stomach of the lion. And, curiously enough, this stomach is the only organ of digestion which the ant lion has. The stomach has no outlet and everything that is not digested must wait within it until the change of life brings on this winged state, when, like a tiny egg, the gathered excreta of the weeks and even months of feeding is thrown out from the body. Perhaps this strange structure of the beast has something to do with the fact that it can live six months at least without a particle of food.

THE SCORPION FLY

(_Panorpa confusa_, Westw.)

When the scorpion fly, standing still, raises above its head that pair of pincers which forms its tail, it seems almost like some two-headed monstrosity.

It is interesting to know that the great Aristotle knew these insects and thought of them as winged scorpions. It is only the males which have these curious tails.

One might easily mistake the long snout for that of some sucking insect, but at the very tip there are two oblong, plate-shaped jaws, each armed with two very sharp teeth which enable the creature to live a carnivorous existence. Although little is yet known about it, the scorpion fly appears, like a hyena, to live chiefly on dead animal matter, although it has been seen to attack injured or helpless insects.

A SOLDIER TERMITE

(_Termes flavipes_, Koll.)

Although too poor a photograph, perhaps, to be worthy of a place in this collection, I have a sentimental reason for its reproduction here, for it brings to mind the days I spent in Java lying flat on the ground studying the mushroom gardens of its tropical relatives.

There are few more interesting creatures than these termites. They have been mushroom eaters and mushroom growers for thousands of years. They have their kings and queens, their workers and their soldiers, and they build gigantic caverns and tall mounds out of earth and half-digested wood.

They tear to pieces and reduce to powder the dead trees of the tropical forests.

Their nymphs, the young kings and queens, are winged and perform a marriage flight, then, tearing off their own wings, they settle down to form a home of dirt and start a new and numerous colony.

They seem to be upon a higher plane of social life than are the true ants, with which they are not in any way related, for the members of a species seem all to be quite friendly towards each other even though they may come from widely different nests. This is never true of ants.

Their queens are strange, egg-laying machines as large as a man's thumb, and they lay an egg a second for nobody knows how long.

The workers shun the light and make long, covered ways of mud in which they go from place to place. With their untiring energy they honeycomb the building timbers of houses and ships in the tropics, making mere hollow shells of them, and so causing disasters of all kinds.

Some of their soldiers have mandibles so strong and sharp as to drive away all animals and make them formidable enemies of man, and some have squirt guns in their heads with which they spray their enemies with an obnoxious fluid.

This tiny representative is all we have in Maryland, but though so small and quiet in his habits he does great work among the pine stumps of my place. The stump of any pine that is felled one year can be kicked out the next, honeycombed with the chambered runways of this creature. Beware lest any pine timbers of your house are near the ground and become infested with termites.

THE STINGING INSECTS

(_Hymenoptera_)

This order is another one in which it takes an entomologist to see the characteristic likenesses in the various species of insects composing it. They all have membranous wings, and all the females have either a saw, an ovipositor or a sting at the tip of the abdomen. One may say, indeed, that practically all the stinging insects are in this order.

Bees, wasps, ants, gall flies, saw flies, and ichneumon flies are Hymenoptera, the ants coming into this membranous winged order because the males and females are winged for the marriage flight, and lose them only after this is over.

This is considered the highest order of insects because it contains members with the most marvelously developed instincts of any creatures in the world, insects whose habits, skill and industry excite our admiration and wonder. Whether they live in colonies with highly developed social states, or whether they live the lives of solitary hermits, their industry and sacrifice to keep alive and perpetuate their kind, are things that make us wonder whether, after all, we have the right to call ourselves the most altruistic of living creatures.

It is around these Hymenoptera that centers the great question of what instinct is, and how it differs from intelligence. We cannot help but feel that it is memory of some kind, not necessarily like the memory of our own brains, but a race memory, transmitted in the almost microscopic egg laid by the mother before she dies.

The instinct of the bee, or wasp, or ant is quite a different kind of thing from reason. Since these creatures have stood still in their development, or at least have changed but little since tertiary times, it is quite possible that their present state represents the highest type of evolution along the lines of instinct. The power to reason, to meet a new emergency, are things which came much later in the development of the world, and man, the creature having them in the highest degree, seems destined to control all other creatures in the end.

THE PORTRAIT OF A BALD-FACED HORNET

(_Vespula maculata_, Linn.)

I wish I could convey to you my sensation when, in hunting for the focus on my ground glass, this creature burst upon my sight. It was as though, exploring in some strange land, I suddenly stood face to face with a beast about which no schoolbook had ever taught me anything. It peered at me out of the gloom of imperfect focus, and it took me some time to realize that I was looking into the eyes of a bald-faced hornet.

There is no wild creature in the northern United States that a man will run away from so fast as from a bald-faced hornet.

At the tip of her flexible armor-plated abdomen is the poison-fed stiletto with which she drives off enemies from the nest or paralyzes her prey.

Her six powerful legs are spined to help her, no doubt, in climbing over the smooth surfaces of flowers and twigs. She has two kinds of eyes--three lens-shaped ones on top of her head and two marvelous compound ones composed of hundreds of little lenses, which take up half the head. Just what she uses each kind for is still unknown.

From her forehead hang ringed antennæ, which doubtless are the organs with which she scents the presence of her prey, and they may also help her find her way about.

Her massive jaws lie below her eyes and look like shears with jagged edges; they are meant for crushing, not for grinding, and with these she tears to pieces bits of wood and cements the particles together with the sticky secretion of her salivary glands, making thus the combs and shelter of her wood-pulp paper nest.

She is an undeveloped female, but with the professional care of a baby's nurse she tends her sister hornets in the nest. On the wing, from daylight to dark, she scours the country for the flies and other insects with which to feed the young. Of all the fly-destroyers which frequent the house she is perhaps the most efficient, pouncing upon the flies with murderous voracity, tearing off their heads and legs and wings, and macerating their bodies to a pulp to feed the hungry grub-like baby hornets which are hatching out in the paper nest over the front door. Her life, and the life of every other worker, is ended by the autumn, and it is left to a few of the young queens to carry on the species.

Does this picture represent, I wonder, one of the nightmare visions which haunt the dreams of baby flies?

THE QUEEN HORNET

(_Vespula maculata_, Linn.)

The summer was over but the cold weather had scarcely begun when I found this creature under a rotten log in the pasture. The paper nest over the front door was empty and rapidly falling to pieces, but even so, it was hard to believe that the active, dangerous creatures we had watched for so many weeks had suddenly disappeared, and that, of the whole busy colony, only a few females were left.

There is something fascinating in the picture of the young queen hornet, after mating is over and all her relatives are dead, crawling away beneath some log and passing there the long cold winter. Then, when spring has come, she emerges from her sleep, the only survivor of her race, and builds, unaided even by her mate, the beginning of a nest just large enough to hold her first-laid eggs. From these hatch out the grubs, which later, after days of feeding, emerge as workers, undeveloped females, and help build up around her a colony of hundreds of busy hornets.

The death of the wasp and hornet workers does not seem to be a matter of cold alone, for, in the regions of perpetual summer, the workers of many species live short lives. They feel the cold, of course, as all our insects do, and inside the nest, on the shelves formed by the flat tops of the combs where the larvæ live, they find dry roosting places at night. The heat of their own bodies materially raises the temperature inside the nest.

Though many people think them just alike, the bees and wasps (the hornet is a kind of wasp) are very different creatures. The wasps have trim, slender forms with a few scattered hairs upon their bodies, whereas the bees are generally hairy and short bodied. They both build combs, but the wasps make theirs of paper wetted with saliva, while the bees build theirs of wax secreted from their bodies. The wasps depend upon fresh food gathered in the day's hunt through the air, whereas the bees store up their food in empty cells. The wasps' nests are the wigwams of a season, the bees' hives the more permanent abodes of a higher type of social beings.

THE YELLOW JACKET

(_Vespa carolina_, Dru.)

Who has not wished that these brown and yellow striped creatures would build their nests where people could see them and be warned to stay away, instead of underneath the ground as they do now.

They hunt in flocks, and it is no wonder that with the sides of their heads all eyes and with three other eyes on the top of the head they should quickly find anyone who treads on their underground nests.

ONE OF THE SOCIAL WASPS

(_Polistes metrica_, Say)

No insect's nest is better known than the small, hanging, paper comb of this social wasp. You find it under eaves and suspended from the ceiling of the porch and from the rafters of the barn. Then, as the cold days of autumn come and the workers and males of the colony die off, their hibernating queens seek shelter from the cold in our houses.

In the spring these queens start out to build a few small, paper cells with finely chewed up fibers of wood wet with sticky saliva. In these they rear up workers to help add new cells and gather food for a new family, and before the summer season has rolled by, the few small paper cells have grown to several scores.

If you have the hardihood to stand quite close to one of these nests you will see the grubs with hungry-looking mouths, wiggling and stretching out their necks, each in a cell quite open to the air, waiting to be fed by its sister or the queen. As to which will come forth from these white grubs as queens, which as males, and which are doomed to be but workers--undeveloped females--nobody can foretell, but certain it is that there will be all three of these forms represented.

A MUD DAUBER WASP

(_Sceliphron cementarium_, Klug)

Think of all the marvelous mechanism and chemistry required in order that a wasp may feed its young upon fresh meat!

The solitary wasps have stings whose venom is much less powerful than that of the bees. Fabre declares that his experiments convince him that the reason may lie in the fact that for paralyzing its prey the wasp needs only a weak poison whereas when the bee stings it does so in self-defense and it stings to kill.

The busy mud dauber females build their nests of mud brought from the nearest puddle and in each carefully made cell lay an egg and around it pack the paralyzed insects on which the voracious little grubs begin to feed as soon as they hatch out.

By the time the young grubs have eaten up the food that has been so thoughtfully supplied by their parents and have changed from grub to pupa and emerged as flying, stinging wasps, their parents are dead and gone. Imagine, if you can, a civilization in which the mothers slave for offspring which they never see, and the children grow up with no education, yet possessed of all the knowledge that their parents had. As Sharpe remarks, the solitary wasps are among the most instinctive creatures of the animal kingdom.

THE FOOD OF A MUD DAUBER'S BABY

This little white spider I found in the nest of a mud dauber wasp.

How long this white spider would have lived its paralyzed existence I do not know. Fabre has watched insects so paralyzed for six weeks, and this one was on my table for several weeks in June without moving and without showing any sign of decay.

We are accustomed to think of the wonders of cold storage as a result of this age of invention, and to look upon its achievement as the accomplishment of the human brain. The mud dauber, in common with most of the so-called solitary wasps, possesses the means of paralyzing the nerve centers of its prey and thus preserving it alive for weeks in the nests of the baby wasps. With the most amazing aim it darts its poison sting between the joints in the armor plate of its victim and touches with a drop of poison one of the nerve ganglia which lies on the abdominal side of most insects.

Fabre has shown that the same result can be produced by a needle and a drop of ammonia, and insects paralyzed in this way hang, as it were, between life and death for weeks or months. If too heavy a dose is given the insect dies in a few hours and putrifies in a few days, and if given too light an application it soon recovers. Different insects require different amounts of the poison to paralyze them and the solitary wasps make mistakes just as man would do. According to Fabre these insects have also discovered that in certain species of their prey the nerve ganglia are grouped close together and can be easily reached with the poison while in others the ganglia are separated, and each ganglion must be touched.

It is a weird thought that for thousands of centuries these creatures have had a perfectly satisfactory way of preserving and storing fresh food while man still kills his animal food and is now quarreling as to how it should be stored and whether if frozen for months it is really good to eat.

THE FIG INSECT ON WHICH DEPENDS A GREAT PLANT INDUSTRY

(_Blastophaga grossorum_, Grav.)

Into every dried Smyrna fig that you eat a queer little beast like this has crawled; unless she does so, no seeds will form, for the inside of a young fig is filled with flowers waiting to be dusted with pollen and it cannot develop until this is done. This tiny, female wasp, so small you can scarcely see her with the naked eye, is the pollen duster of this miniature flower garden.

The Blastophaga hatches out from a tiny egg which her mother lays in a special flower or gall in the flower cavity of a wild, inedible Caprifig that came originally from the islands off the Syrian coast. Her mate, an ugly little thing with no wings at all, hatches out before she does and mates with her even before she comes out of her tiny cocoon. After wandering about among the stamens in the cavity in the Caprifig until her back and sides are covered with pollen, she finds her way out through the hole in the end of the ripening wild fig and flies away in search of another young and ripening fig in whose gall flowers instinct impels her to lay her eggs.

The larger, juicier Smyrna fig attracts her, and she crawls inside, searching for gall flowers there. But the Smyrna fig has no special places for her eggs and, after wandering around over the flowers in the floral cavity she wanders out again, or dies. But in this scramble over the sticky stigmas of the Smyrna fig flowers, she irritates them and leaves upon them the pollen which she brought with her from the wild fig. This is what causes the young seeds of the Smyrna fig to grow and the fig itself to swell and become the honey-sweet fruit which we eat.

Without the visits of this tiny wasp the figs either fall off on the ground when young, or else form insipid tasteless fruits. So it might be said that the great fig industry of Smyrna hangs on the blundering instinct of this little creature.

Some enterprising Californians brought over and planted orchards of the Smyrna fig and could not understand why they did not bear. Then they brought in the wild Caprifig from Smyrna and planted it side by side with the Smyrna figs, but still with no result. Finally the experts of the Department of Agriculture were called in and solved the problem by introducing the insect, which had been left behind.

This little creature, in the picture, crawled out in my laboratory from a Caprifig which Doctor Rixford, the fig expert of California, sent me, requesting that I photograph his pets.

THE COW KILLER OR VELVET ANT--A WINGLESS WASP

(_Mutilla simillima_, Sm.)

Can you imagine an insect daring enough to brave the stings of the thousands of workers in a bee's nest? This wingless, solitary female ant lives habitually in their nests and eats the food they have so busily gathered, an unbidden and probably a most unwelcome guest. Powerful jaws, formidable sting, an armor-plated shell to protect her from the stings of the bees and wasps in whose nests she lives, seem to fit her for the strange life she leads.

If you should find her mate he would doubtless be on the wing, for unlike all others of the order, it is the male alone which flies. So different from their mates do some of these male cow killers look that they have often been mistaken for quite different species.

It is supposed that the female lays her eggs inside a bumble-bee grub and in a few days' time they hatch and eat the babies up, from the inside outwards. Then they hatch again, so to speak, as full-fledged cow killers and feast upon the honey of their hosts.

THE WORKER BUMBLE-BEE

(_Bombus vagans_, Sm.)

Everybody has a friendly feeling for the bumble-bee, that clumsy rover of the clover field whose buzzing seems part of the still summer air. She is the real worker of the hive, an undeveloped female, her hind legs laden with a mass of pollen from the flowers she has visited, and her honey sac filled with nectar.

As every boy who has hunted her nest will know, the bumble-bee lives in burrows under ground.

The cells that she makes are of wax, secreted from special plates which lie arranged in rows beneath her hairy body. Each cell is like a little jar, standing on end, quite different from the cells in a honey bee's comb. In some of these the eggs are laid and the baby bees hatch out, while others are filled up with nectar.

While the bee is gathering pollen with her legs, she is also gathering nectar with her tongue and storing it in a special honey stomach from which she later regurgitates it into the honey cells in her nest.

The nectar, when it is gathered, is thin, like the sap of the maple tree, and, like it, must be condensed. Part of the water seems to be taken out in the honey stomach, and part evaporates from the honey cell.

It will, perhaps, be a satisfaction to those who hate getting up early to know that there is a well-founded rumor that some bumble-bees have a trumpeter who, somewhere between three and four o'clock in the morning, wakes up the sleepy hive.

THE POLLEN PLATES OF THE BUMBLE-BEE

(_Bombus americanorum_, Fab.)

If you will watch a bumble-bee closely as she crawls over the stamens of a wild rose, perhaps you can see that, although she covers the whole under part of her body with pollen, yet she scrapes off all she can with her feet and packs it in a yellow mass on the smooth, hairless segments of her large hind legs, the pollen plates as they are called. To make the pollen stick on these smooth plates and hang together during the flight to the nest, it is claimed by Muller that the bee mixes nectar with the pollen grains. The kind of pollen that she gathers is, however, not generally the dusty kind, like the pollen of the pines or grasses, but the sticky kind that comes from insect-fertilized flowers. When the bumble-bee reaches her nest, she scrapes the pollen from the pollen basket and with it feeds the young, for pollen is the solid food of baby bees.

There is one strange thing about these smooth pollen plate legs which, from our human, individualistic point of view, is hard to understand. It is only the workers, the undeveloped females, which have them; the legs of the males and of the queens are hairy and are not at all adapted for pollen gathering. Thus, since workers bear no children, we see a race of parents transmitting to certain of their offspring characters which neither they nor any of their ancestors have ever possessed.

THE BUMBLE-BEE AT WORK

This photograph shows the great hybridizer at work.

She is on one of the single roses, her hairy body spread over the stamens which, with their yellow anthers, look like a circular bed of tulips. In the middle of the circle, where her right foot rests, is the stigma.

If you will sometime take a hand lens and watch a bee at work (and if you don't get too close she will pay no attention to you), you will notice the clumsy way she crawls about, knocking the pollen off the stamens and getting her body covered with the yellow dust. As you watch, any feeling of there being some mystery about cross fertilization will be dispelled. How this same bumble-bee could crawl across another rose blossom _without_ leaving a trail of yellow pollen on its stigma would be the mystery!

Since the earliest days of the world of plants and insects, the bumble-bee and her ancestors have been at work mixing the pollen on hundreds of different plants and playing, doubtless, a perfectly gigantic role in the creation of the flowering plants which now cover vast areas of the globe.

It is perhaps an idle speculation, but it would be interesting to know how many plants would become extinct were some disease or parasite to exterminate the bees.

THE TELLTALE MILKWEED POLLEN

(_Bombus sp._)

Although this bumble-bee was caught in flight across my meadow, her photograph shows beyond the shadow of a doubt that she had been a recent visitor to the blossom of some milkweed, for, projecting from her right hind leg and plainly visible, are the pollen masses of the milkweed flower. They look like little paddles and hang in pairs, although this you cannot see in the picture.

We know that flowers depend upon the bees to fertilize them, but somehow I do not think we grasp the completeness of this dependence, nor realize how many flowers there are which, unless they have their own pet insect visitors, would soon become extinct.

The milkweed lures its visitor with little cups of nectar, and beside each cup it sets a trap which is as carefully worked out as the steel traps which the modern trappers use. Across the top of a little slit, wide below and narrow above, lie the small ends of the paddles or pollen masses, firmly joined together. As the bee alights to sup the nectar, her foot slips into this crack, and in trying to extricate it she pulls up the pair of paddles which fasten themselves onto a hair of her leg like a clothespin on a line. In drying, the paddles clap together in such a way that by the time another milkweed flower is visited they can slip with the leg right into the little slit and are broken off and left there as the bee again pulls out her leg. Once inside, these pollen grains throw out a score or more of tiny, rootlike tubes which grow into the lining of the slit and carry to the ovary below the fertilizing germ plasm which makes the seed develop.

The bumble-bee, of course, is strong enough to slip into these traps and pull her legs out as a routine thing, but many small moths and butterflies are not, and these get caught and die upon the blossoms.

THE POOR MALE BUMBLE-BEE

(_Bombus americanorum_, Fab.)

It was late in October before I noticed, flying low here and there across the clover tops, large bumble-bees, which seemed to be more covered with golden hairs than those which I had watched throughout the summer time. At first I thought them queens, but as their number multiplied I felt I must be mistaken, and one of my insect-knowing friends explained that they were only males, and that with the approaching days of winter they were all doomed to death. Already, he pointed out, their wings were battered and frayed from flying against the autumn winds.

The importance of the males! Could there be a weaker argument against woman's suffrage than the one which has been brought forward that throughout nature the duty and the right of protection rests with the male? Perhaps the drones do fight among themselves; but, as in most other fighting of the males, it is not to protect the nest or young from perishing, but merely to determine which one of them shall win the queen's attention. The males are stingless.

In this world of the clover field all the work of the society is done by the queen herself, or by the workers, which are infertile females. Apparently few males are wanted in the colony until late in the season, when, for a brief period, they are tolerated in considerable numbers as the necessary courtiers who accompany the young queens of late summer in their marriage flight. This takes place before the winter comes to kill all but a few fortunate queens, which find safe shelter in some crevice in the rocks or underneath some old, decaying log.

SOLITARY LEAF-CUTTING BEE

(_Megachile brevis_, Say)

Unlike the social honey and bumble-bees, this bee leads a solitary life.

With her strong, saw-like jaws, the female makes her burrow in soft wood and lines it with bits of leaf which she has cut from some plant. When the leaves of plants in the garden have large round holes in them, in nine cases out of ten you may be sure that they have been cut by some solitary bee.

When the burrow is complete she makes a ball of pollen and nectar, puts it in the bottom of the burrow, lays an egg upon it, and, with a wad of leaves, securely shuts it in; over this she lays down another food ball with its corresponding egg, and so on, until the burrow is full.

THE STINGER OF THE LEAF-CUTTING BEE

(_Megachile brevis_, Say)

The sting or "stinger" of a bee is indeed a most wonderful piece of mechanism. At the base, inside the body of the bee, lie bars or levers, operated by muscles, which push the darts out and draw them in. The poison sac lies just behind this mechanism and pours the poison into a set of cup-like valves, from which it escapes into the wound along longitudinal grooves in the sting like grease along the piston of an engine.

The sting itself is not, then, hollow, like the spider's poison fang, but is a poisoned stiletto as long as the bee's foreleg which she can thrust in and out with incredible rapidity, and which, as everyone knows, can inflict a painful wound on creatures millions of times her size.

A COMMON RED ANT

(_Formica sp._)

Ants are undoubtedly the highest, structurally and mechanically, of all insects, and at the same time the most efficient. Their social organization has been the admiration of human beings from the earliest times, because the interest of the individual is merged so completely into that of the colony; but, as Wheeler remarks, their organization must strike the individualist with horror.

It is an organization of females, too. The workers are females, the soldiers are females, the nurses are females, and there is one queen mother for them all, who lays all the eggs of the colony. Where are the males, those representatives of society, those voters of our human colonies? They do not exist as such, for the males of ant colonies are but mates for the young queens. Together with them they leave the nest on their marriage day and together make the marriage flight, but as soon as this is over they die, and the colony gets on easily without them.

To man, who is the most rapidly evolving organism on the earth today, it is a strange thought that the most highly developed insect which the world has produced, and which has not changed materially since the Tertiary epoch, has relegated the males to the short-lived function of reproduction, leaving him no work to perform and getting rid of him as quickly as possible. Why did the ants, with their marvelous instincts, fail to conquer the world? Why have they stood still for thousands of years after they had perfected their social organization? Did they go as far as evolution could go when it leaves the male out of account? It is perhaps a comfort to think that, after all, they have failed and the man-guided organization of human beings has surpassed them in its development!

A BLACK ANT

It is strange to think that just because the sunlight which poured upon this little creature's shiny body was reflected back against a photographic plate, its rays being made to diverge widely in so doing, we can get an image of this tiny ant as large as though it were a mouse.

What a world this would be to us had we microscopic vision! A thousand times as many beasts to look at, a thousand times as many things to see and understand!

ANT GATHERING NECTAR FROM LEAF NECTARIES OF THE CHINESE WOOD-OIL TREE

A year ago I planted in my garden in Maryland three young wood-oil trees from the Yangtse valley of China, broad-leaved trees something like the catalpa. Just where the leaf stem joined the leaf blade there were two curious, dark red, oval glands. The use of these I did not understand until one morning I discovered a big black ant on each leaf, and each ant was stationed at the base of its leaf near these glands and evidently was lapping up from them small drops of nectar which kept oozing out from the center of each gland.

These rapidly-walking little creatures, which spend their time roaming everywhere, had discovered the use of these nectar glands although they were on the leaves of a plant which they had never seen before.

Whenever I touched a leaf the ant upon it ran about as if to frighten an intruder away, and I could not help but wonder if in China, where the wood-oil tree is at home, there might not be some stinging ant which takes upon itself to protect the foliage from the attacks of caterpillars, and gets, in payment for its labor, the nectar from these glands. The tropics are full of such agreements between the plants and the ants, and very effective ones they are, too.

The photograph shows a black ant with antennæ extended, reaching over one of these big glands for the drop of nectar which glistens just below its head. On the other gland, just back of the ant's left antenna, a second drop of nectar can be seen.

First one and then the other of these nectaries is licked clean by the ant, and so well was the work done that throughout the summer it was only when I visited the leaves in early morning, before the ants were out, that I could find the beads of nectar in their places in slight depressions in the glands.

THE ICHNEUMON FLY: ENEMY OF THE SPIDER

(_Crypturopsis sp._)

It would seem as though the spider ought to be able to protect itself from such a beautiful creature as this, but she is said to be one of the spider's worst enemies. With the long ovipositors which may be seen in the photograph and might almost be mistaken for her sting, she lays her eggs inside those of the spider and the larvæ hatching from them eat up the spider's eggs. It is, so to say, an insect cuckoo, or worse than that, for the bird cuckoo only crowds the real children out of the nest, whereas the ichneumon fly devours them.

From man's point of view, however, many of the tribe to which this so-called fly belongs are his good friends, for they hold in check some of the pests which molest the plants he lives upon.