Book of Monsters Part 16

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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.

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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--n.o.body can foretell, but certain it is that there will be all three of these forms represented.

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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.

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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.

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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 coc.o.o.n. 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.

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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 sh.e.l.l 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 b.u.mble-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.

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THE WORKER b.u.mBLE-BEE

(_Bombus vagans_, Sm.)

Everybody has a friendly feeling for the b.u.mble-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 ma.s.s 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 b.u.mble-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.