Chapter V: Part 5

Deadliest of serpents are the Pacific sea snakes. A bite almost certainly would be fatal to a human being. Yet native children of the Palau Islands in the South Pacific play with these reptiles with complete impunity. They pick them up and toss them from one to another just as American children play “catch.” Natives of the Palaus look upon the reptiles with complete indifference.

The term “sea snake” is somewhat of a misnomer. Actually the creatures spend most of their days asleep among rocks on beaches. They are excellent tree climbers and like to sun themselves in crotches of branches. At dusk, however, they move out to the reefs where presumably they spend most of the night pursuing small fishes, their principal food. They are excellent swimmers and their bodies have been somewhat modified, with flattened, paddle-like tails, for sea life.

Fortunately, on land at least, they are sluggish and non-aggressive. They hardly can be induced to bite and will suffer almost any indignity without retaliating. About the only way a person would be likely to be bitten would be by stepping directly on the head of one of these snakes with bare feet. This is an unlikely event, for the sea snakes do not spend any time under shallow water where they would be a peril for bathers.

Some are quite beautiful, about five feet long and banded with black and white. Their capture is easy. It is simply a matter of pinning down the head with a stick and picking up the snake by the neck.

Throughout the entire sea snake area in the Pacific there are only five or six instances reported where the serpents have bitten humans. In every case the victim has died; there is no anti-venom against the sea snake toxin.

Some years ago Dr. Herbert Clark, former director of the Gorgas Memorial Laboratory, dove off a boat in Balboa harbor and swam ashore, a distance of about 200 yards. As he neared the shore there were alarmed cries from the deck he had left. Dr. Clark looked around. He found he had unwittingly swum through a school of several thousand black and white serpents, each about two feet long. None had touched him.

_Weird Plant-Animals_

Near the bottom of life’s pyramid there is a weird race of plant-animals. They are among the closest of all many-celled living things to the primaeval protoplasm from which all life arose.

They are the slime molds found on decaying logs and tree stumps in damp woods or on piles of rain-soaked dead leaves in shady gardens. The nightmarish mycetozoa—botanists call them myxomycetes—are timeless survivals out of living creation’s dank, warm cradle. Some of the weirdest imaginings of malevolent life on other planets picture it in the form of gigantic slime mold aggregations—undifferentiated masses of naked protoplasm endowed with a malign intelligence which has evolved without the intermediaries of nervous systems or brains.

These organisms can be considered one of nature’s probing experiments towards higher forms of life. The experiment was a failure, but unlike most of nature’s discards these organisms have survived. Even now they may be engaged in a process of evolution all their own.

Biologists are not entirely agreed in which kingdom to place the organisms, although they usually are classified with the plants. They start life as spores, like the dust of molds or toadstools whose single-celled particles serve the same reproductive function as seeds in higher plants. From each spore arises from one to four animal-like organisms, hardly distinguishable from the one-celled protozoan animal, the amoeba. Each swims about freely for a time by means of tentacle-like arms, the flagellae.

These free-moving living particles are known as “swarm cells”. Each is an individual with a film-like skin separating it from all other individuals. That is, the protoplasm of each cell is enclosed within a boundary and in the center of each is a nucleus. These one-celled “animals” wander about freely for a few days. During this time they may mate, as individuals. More commonly each loses its flagellae and splits into several fragments. Each of these fragments becomes a complete organism. These mate, with complete fusion of their bodies. The result is a double plant or animal—depending on whether it is observed by a botanist or zoologist—known as a zygote. The fragments are extremely voracious little creatures devouring greedily the one-celled plants, or bacteria, which they encounter.

When the fusion is complete the zygote, in turn, starts to split up into single-celled organisms but after a few divisions hundreds of these single-celled animals coalesce into a tiny ball, like the seed pod of a plant. In a few days thousands of these spheroids collect into a so-called “plasmodium”. The hitherto individual pseudo-protozoans meanwhile have lost their cell walls. The primaeval substance of millions is mixed together into a slimy mass full of cell nuclei. This is an aggregation of “naked protoplasm”. It is hardly to be compared with the body of any higher plant or animal where each cell retains something of its individuality, however closely its activities may be coordinated with those of its fellows in the same community. The mass proceeds to behave like a voracious animal. It moves and feeds as a unit and apparently with a purpose. Within the naked protoplasm there is apparently some incomprehensible sense of fellowship which eventually evolves into consciousness and intelligence, developing nerve and brain on the way upwards. It would be hazardous to say that this evolution could have taken no other path.

From the central body great numbers of thread-like filaments are sent out to penetrate the substance of rotting wood or the surface of a dead leaf. These threads seem to be like an army’s scouting parties, pushed ahead to locate supplies when advancing troops are living off the country. When a supply is found they are drawn in and the whole slimy organism acts once more as a coordinated whole.

The plasmodium moves forward steadily for about 50 to 60 seconds, pauses for a few moments, and then reverses itself and creeps backward, but never quite so far as it previously had gone ahead. Then, after another pause, it crawls forward again. Thus there is an overall slow advance and at the bottom of life the slime molds lay down the pattern of progress recapitulated in human societies and civilizations as well as in the lives of individual men and women. They merit consideration in the philosophy of history.

The advancing mass of raw protoplasm acts like an animal and grows like an animal as it ingests food, with constant splitting of the cell nuclei which it contains. There are vacuoles within the protoplasm in which the food particles are ingested. They then are digested by means of enzymes (body chemicals), as in higher animals.

Such a plasmodium can be taken from its damp habitat and dried. Then it will roll up into a ball and pass into a resting stage from which it will revive completely in a few hours when supplied with moisture again. The ball may keep its vitality for several years.

Some species pass as much as a year in the active plasmodium stage, and some a few days. At the end of this phase of its existence the mass of raw protoplasm breaks up into fragments—sometimes as many as a hundred. Then, as the process is described for one common species “in an hour or two each of these fragments has risen into a pear-shaped body with a narrow base, a dark stalk being just apparent through the translucent white substance.” In about six hours the black, hair-like stalk has grown to its full length and bears at its top a young “sporangium” consisting of a globule of viscous plasma with a diameter about a fifth the length of the stalk. This globe is about the size of a mustard seed and ranges in color from pure white through golden-yellow, light crimson, violet, purple and black.

A pink flush now begins to pervade the sporangium caused by the formation of branching threads. The nuclei in the plasma still present the same appearance as those observed in the streaming plasmodium. In about another hour these nuclei show the beginning of division. As this process develops the plasma becomes separated in masses of two spores capacity. An hour later the nuclei have divided and the young spores are forming. Their color rapidly changes. In about the first twenty hours after the first concentration of the fragments of the plasmodium they have matured and present the appearance of minute black pins standing in regular order on wood. The ripe fruit, or sporangium, then dries and breaks.

On placing the spore in water its membranous wall slips off and the naked contents lie for several hours without apparent change in an ellipsoid form. Constriction then takes place and the ellipsoid splits into one to four globular bodies adhering together and exhibiting slow amoeboid movements. Each globular body now develops a flagellum—a long, whip-like extension, and the cluster swims away by means of these flagellae.

Now the whole life process is ready to be repeated. There are more than 400 species of these slime molds and they are distributed over all the temperate and tropic zones. If only the spores and the stalked little ball containing them are considered, the slime mold would be placed squarely in the kingdom of plants. But when the protoplasm escapes from the spore and starts moving about ingesting bacteria, the behavior is that of a one-celled animal. When the cells unite to form a plasmodium there is a close likeness to a many-celled animal.

_Weird Ways of Birds_

Among the most fantastic forms of animal behavior is that of the honey guides, African birds distantly related to the American woodpeckers. They “guide” men, baboons and ratels to the nests of wild honeybees—supposedly so that these nests will be broken open.

Throughout the three centuries since the unusual behavior of the bird was first reported by a Portuguese missionary it has been the subject of many fantastic accounts, some of which attribute a far higher degree of intelligence to the birds than they possibly could possess.

A long-continued study of this behavior has been made by Dr. Herbert Friedmann, Smithsonian curator of birds. Dr. Friedmann himself has observed at least 23 instances of the habit and has collected much other well authenticated data from African associates. He describes the behavior from his own observations:

“When the bird is ready to begin guiding it comes to a person and starts a repetitive series of churring notes, or it stays where it is and begins calling these notes and waits for the human to approach it more closely. These churring notes are very similar to the sound made by shaking a partly full, small matchbox rapidly sidewise. If the bird comes to the person it flies 15 or 20 feet from him, calling constantly and fanning its tail.

“It usually perches on a fairly conspicuous branch, churring rapidly, fanning its tail, and ruffing its wings so that at times its yellow shoulder bands are visible.

“As the person comes to within 15 to 50 feet the bird flies off with a conspicuous initial downward dip, and then goes off to another tree, not necessarily in sight of the follower, in fact more often out of sight than not. Then it waits there, churring loudly until the follower again nears it, when the action is repeated. This goes on until the vicinity of the bees’ nest is reached. It waits there for the follower to open the hive and usually until the person has departed with his loot of honeycomb, when it comes down to the plundered bee’s nest and begins to feed on the bits of comb left strewn about. The time during which the bird may wait quietly may vary from a few minutes to well over an hour and a half.”

African natives regard the bird as an almost infallible guide to honey. They try to attract it by grunting like a ratel or chopping on trees to imitate the sound of opening a nest. The habit is apparently instinctive; it presumably originated before human beings appeared, perhaps starting with the ratel or some of its honey-eating ancestors.

Curiously enough, the honey bird does not seem interested in the honey, per se, or in the grubs of bees found in the nests. It has an insatiable appetite for the wax, which it will take wherever it can be found. The first account of the bird was of an individual which fed on the wax candles of a church. It appears to have a peculiar ability to digest wax presumably to extract the nutritive elements contained.

_The Fantastic Sea Horse_

A fish with the head of a Lilliputian horse, the tail of a monkey, the shell of a beetle and the pouch of a kangaroo...a creature that reverses the ordinary course of nature in that “child bearing” is exclusively a function of the male.... Perhaps in no other animal have been packed so many anomalies as in the little hippocampus, popularly known as the “sea horse”.

These weird creatures are almost world-wide in their distribution through ocean waters where there are growths of sea vegetation. They have provided the models for some of the monsters of human nightmares. Actually they are small, feeble, almost defenseless creatures.

The head unquestionably is similar to that of a miniature horse in general outline. The neck, however, is not a neck at all. Fishes have no necks and hippocampus is no exception. What looks like a neck is the upper part of its abdomen, considerably contracted.

The body is covered with a jointed, chitinous shell, like many of the insects. This peculiarity left early naturalists in doubt as to whether it actually was a fish or some sort of monstrous water bug. It is, of course, a true fish with no insect affiliations. The hard shell makes it a feeble, inefficient swimmer. It is able, in fact, to swim at all only because of a large air bladder so delicately adjusted to the specific gravity of the animal that if a gas bubble the size of a pinhead is let out by a puncture the sea horse sinks to the bottom. There it can only crawl about clumsily until the wound is healed.

Because it is so poor a swimmer the hippocampus must have other means of adjustment to its salt water environment. This is afforded by a prehensile tail which it can wrap around the stems of water plants. This kind of a tail is found among a few mammals, notably the smaller monkeys. So far as is known, no other fish has anything of the sort. The animal is most frequently observed in a state of rest, its tail wrapped around a plant and its body standing nearly erect in the water.

Its food consists of tiny crustaceans and other sea organisms of like size. Because of its poor powers of locomotion, it must wait for those which come within reach of its jaws which work with lightning-like speed, or for those which will wait accommodatingly for it to come and get them.

Hippocampus can move its eyes independently of each other, thus looking backward and forward at the same time. It would be rather difficult for a predaceous organism to take it by surprise, but on the other hand it would have little ability to fight back or flee if attacked. Some species, at least, have considerable ability to change color to blend with the environment. Bright red, pink or yellow specimens when caught fade rapidly to normal mottled gray.

Probably the greatest anomaly of the hippocampus family is its way of reproducing the species. The male actually “gives birth” to living young. The process, so far as known, is unduplicated in nature. Unfertilized eggs are laid by the female. She places them, a few at a time, into a pouch-like organ on the underside of the male’s body. In some fashion still unknown to biologists they are fertilized in the transfer. Within this pouch the eggs are incubated and there the young remain for several days after they are hatched. Then, fully equipped to take care of themselves, they are expelled into the water. So far as has been observed, there is no further parental interest in them. This male pouch might be considered as filling the double function of the womb of a placental mammal and the pouch of a marsupial like the kangaroo.

The sea horse also has the distinction of being one of the species of fish that “talk”. In recent years “talking fish” have become a matter of considerable interest to the Navy because of the confusion they cause in the interpretation of underwater sounds. They give every indication of talking to each other. They produce loud clicks similar to the snapping of a finger. These also have been compared to the clicks of a telegraph. They were especially notable when an animal was first placed in the tank and apparently was confused by the new environment. It would cruise back and forth across the container, standing upright and its prehensile tail curled over its back, emitting the characteristic sounds at intervals of from a half to three quarters of an hour.

When two sea horses were kept in separate jars adjacent to each other in an experiment it appeared as if they were trying to converse. First one would emit a series of clicks. Then the other would answer. The sounds are produced by snapping the jaws together. In nature these probably are mating calls.

_The Great Seal Migrations_

The great annual northward migration of the seals is one of the most remarkable phenomena of animal life. It seems to be without organization and without leadership, yet toward the end of March each year the hundreds of thousands of cow seals and pups scattered over thousands of square miles of water start at about the same time in three great groups bound for three specific places. It has been the same for centuries, perhaps millenia. Each animal moves at about the same rate so that all arrive within a few days of each other. They do not move in compact masses, like birds.

The American herd of about 1,500,000 is by far the largest of the three. It goes straight to the Pribiloff Islands where it goes ashore on two almost barren islands—St. Paul and St. George. The Japanese herd, numbering about 40,000, makes for Robben Island, off northern Japan. The Russian herd, now estimated at about 200,000, goes to a few rocky islands of the Commander archipelago, off Kamchatka.

The moving herds consist almost entirely of females and young. The bulls winter further north, tend to be solitary during the winter, and precede the cows to the summer homes. The breeding season lasts for about two months. During this time the bull never eats or touches a drop of water. He never leaves the land. He arrives sleek and fat from the ocean pasture and is able to survive entirely on stored energy. This keeps him alive, even when he fights scores of terrible battles with younger rivals. Towards the end of summer he naturally is a sorry-looking creature.

One day, actuated by some common impulse, cows and calves depart. Then the bulls, their arduous labors of race propagation over for ten months, draw back among the rocks and spend two or three days in sound sleep before returning to the sea to replenish themselves.

Cows have very little reserve energy and must return to the water every two or three days, leaving their nursing pups ashore. On her return from one of these feeding expeditions, a cow goes straight to her own pup among the thousands on the rocky beach. Presumably she locates it by the odor. Few animals grow more rapidly than the seal pup. Within a few weeks after birth it is almost as large as its mother. This is an essential provision of nature, for it must have sufficient size and strength to care for itself in the open sea, once the southward migration starts. It is fully the size of the mother when it comes back the next year. There is an old idea that seal pups must be taught to swim. This is denied by government observers at the Pribiloff breeding grounds. When thrown into the water for the first time they swim ashore without difficulty. They will not, however, venture into the sea voluntarily but must be pushed off the rocks by the mothers.

St. George and St. Paul islands are the only two spots under the American flag, except for certain atomic energy and military installations, which are absolutely barred to visitors without special government permits. These, as a rule, are given only to scientists studying the behavior of the seals. On each island there is an Aleut village whose inhabitants attend to the butchering of the animals each summer. This is confined entirely to three-year-old males who congregate by themselves. The only other killing permitted is by Aleuts along the coast for whom sealing is the traditional means of livelihood, but this now is so restricted that the annual toll is very small. The sealing must be done from an open boat, use of firearms is prohibited, and the Aleuts cannot be under contract to furnish skins.

_Monsters With Buzz Saws_

“But if, retaining sense and sight, we could shrink into living atoms and plunge under water, of what a world of wonder would we form part. We would find this fairy kingdom peopled with the strangest creatures—creatures that swim with their hair, have ruby eyes blazing deep in their necks, with telescopic limbs that now are withdrawn wholly into their bodies and now stretched out to many times their own length. Here are some riding at anchor, moored by delicate threads spun out from their own toes. There are others flashing in glass armor, bristling with sharp spikes or ornamented with bosses and flowing curves; while fastened to a green stem is an animal convulvulus that by some invisible power draws a never-ceasing stream of victims into its gaping cup and tears them to death with hooked jaws deep down in its own body.”—_The Rotifera_ by C. T. Hudson and P. H. Goose, London, 1886.

The rotifers or wheel animalcules are fantastic creatures. They were first seen by the Dutchman Antonius van Leeuwenhoek, credited with being the inventor of the microscope. “On the 25th of August,” he wrote to the Royal Society of London with which group of savants patronized by Charles the Second he was in regular correspondence, “I saw in a leaden gutter on the front of the house for a length of five feet some rain water had been standing which had a red color. It occurred to me that this redness might be caused by red animalcules. I took a drop or two of the water and looked at it under the microscope.”

He found a confusion of “red-eyed monsters armed with teeth like those of the balance wheel of a watch, which appear to be projecting forward towards the head. They seem to whirl around with a very considerable velocity, by which means a rapid current of water is brought from a distance to the mouth of the creature who thereby is supplied with many invisible food particles.”

This discovery is of considerable significance in scientific history because, more than any of his previous findings, it caused the Amsterdam spectacle-maker to question the then widely held belief in the spontaneous generation of living things.

“They can,” he wrote the Royal Society in 1774, “continue many months out of water and be dry as dust, in which condition their shape is globular, the bigness exceeds not a grain of sand, and no signs of life appear. Notwithstanding, being put in water, the globule turns itself about, lengthens by slow degrees, becomes in the form of a lively maggot, and most commonly in a few minutes afterwards puts out its wheels and sweeps the water in search of food. But sometimes it may remain a long time in the maggot form and not show its wheels at all.”

Such tiny organisms capable of such long periods of suspended animation, Leeuwenhoek held, could be blown by the wind for long distances. Thus the sudden appearance of living animals in supposedly lifeless water did not indicate they had been born or created there.

The microscope designer had found, moreover, an hitherto unknown race, giants of the microscopic world and among the most fantastic of all animals—the rotifers.

These usually invisible animals with buzz-saws on their heads—the largest not more than a quarter-inch long and the majority less than a twentieth—seem to have gone further beyond life’s normally accepted frontiers than any other animals. One species lives comfortably in hot springs where temperatures go above 120 Fahrenheit. Others can be frozen in solid cakes of ice for weeks and show no ill effects. Sudden changes in temperature, however, often are fatal. On tops of Antarctic mountains projecting out of ice two miles thick, the little rotifers are found among sparse growths of lichens, the only animal life which approaches closely to the South Pole on land. There is no reason why they should not thrive in the hardly less hospitable mountains of Mars. They might have been carried there in light propelled earthdust.

The majority are fresh-water creatures. A few live in damp moss and a few species have obtained a foothold in the sea. Some live in immense colonies, permanently attached to stones. Some are free-living individualists who crawl like leeches, or swim rapidly. Some are parasites in the cells of water plants or in the gills of fresh water crabs. Others cling to floating plants or to water animals, to be carried from place to place. One highly social group lives in free-moving communities of forty or more individuals, attached to each other by their tail ends and radiating from a common center like wheel spokes. The usual color is reddish and most rotifers have one or more glittering red eyes. In a few cases these eyes are inside the bodies of transparent species.

Despite their minuteness, these predatory giants of the world invisible are highly developed animals. Each has a body divided, like that of a mammal, into three major segments—head, trunk, and extremities. In some the skin is hardened into an armor-like covering. Some have a panoply of defensive spines and bristles.

Inside the skin is a cavity full of watery fluid—it contains no corpuscles like blood—in which float the more important vital organs. In most animals there is tissue of some sort in which nerves, muscles, and glands are imbedded. In rotifers, however, there is very little of this connective tissue. Under a microscope one generally can see with some clearness each individual cell. These cells can be counted, for at the most there are only a few thousands, compared to the millions of millions that make up the bodies of larger animals. The muscles are not banded together, but consist of isolated strands whose job is to pull the head inside the armored trunk when faced with any threat, and to bend the body in various directions.

All rotifers have two organs unique to their race. First is the “buzz saw”. This is a crown of tentacles, quite similar in appearance under low magnification to a circular saw, which is constantly whirling. Its purpose is to create eddies in the water which will bring food particles to the mouth, a funnel-shaped opening on top of the head. In free-living species the saw may have some function as a propeller.

Second is the mastax, or “chewing stomach”. Every rotifer has two stomachs, one for masticating and one for digesting. The mouth opens directly into the first. It is provided with two horny, serrated jaws which crush toward each other and tear to bits the minute animals and plants which are the creature’s food. The jaws are provided with several hard parts, adapted for biting, crushing, holding, and tearing.

In the permanently anchored rotifers the rear of the body is prolonged into a stalk from the end of which a cement-like substance is secreted. This permanently attaches the animal to something, usually a stone. In some of the free-living forms the “foot” is replaced by one to twelve “leaping spines” by means of which the owner can spring suddenly forward several times its own length to capture an unsuspecting victim. This is most often some floating one-celled creature of the water-drop jungle, such as a protozoan elephant.

The male rotifer is usually much smaller than the female—sometimes nothing more than an appendage she carries about with her. The fantastic worlds of all sorts of rotifers are predominantly feminine worlds. For some species, in fact, males never have been found, but there is little doubt that they exist.

_Two-Headed Snakes Aren’t Rare_

Two-headed snakes probably are quite common. About 200 cases have been reported. Dr. Bert Cunningham of Duke University, who has studied several living specimens, has this to report about such snakes: “The heads play together, fight over a morsel of food even though it will go into the same stomach through either mouth, attempt to swallow one another, and sometimes fight fatal duels. Each head has a brain of its own. Few grow to any size. In this case two heads are not better than one, especially when they disagree when a second means escape or death.”

_Fantastic Sea Creatures_

Coral-forested waters around the Gilbert and Mariana Islands in the Pacific are yielding some of the most fantastic sea creatures known to science.

Extensive collections have been made since the war by Dr. Leonard P. Schultz, Smithsonian curator of fishes. Notable in the collections are snake, worm and moray eels, all bottom dwellers in tropical waters. Snake eels are, as the name indicates, superficially almost indistinguishable from serpents. On their tails they have hard points which are used as drills. They burrow straight downward in the bottom sand, tails first, until only the heads protrude above the surface. The worm eels belong to the same general group but are much smaller and slenderer—about the diameter of a lead pencil and reaching lengths up to two feet. Larger worm eels have been reported.

Both these groups consist of relatively timid, inoffensive creatures. Far different are the moray eels, members of a closely related family. They are as much as ten feet long, have razor-like teeth, and are described by Dr. Schultz as about the most vicious creatures in the sea. In disposition they probably are worse than the worst sharks and easily can bite through a man’s hand.

Probably the most poisonous creature in the collection is a variety of sting ray, weighing about 200 pounds, which was speared at the bottom of 20 feet of water. This animal, like all stingarees, has a tail armed with long, poisonous barbs. The venom could be lethal to a man. After it was speared, the ray remained very much alive and the problem of bringing it to the surface was difficult. This finally was accomplished by two of Dr. Schultz' collaborators. First one would dive, grasp the handle of the spear, and lift the creature a few feet, always holding it far enough away to be clear of the barbs. After the first man became exhausted, the other would relieve him while he came up for air. Thus the specimen finally was gotten on board through a series of relays.

Curiosities of the collection are the cardinal fishes—brilliant red, very active, and including some of the smallest marine fishes. A few species attain full growth at about three-fourths of an inch. These are the most notable of the “mouth breeders.” The female lays the eggs and the male carries them in his mouth until they hatch. Inch-long males sometimes carry as many as 400 eggs, nearly all of which hatch.

Other curiosities are the pipe fishes, hard-shelled animals which look like bits of small, segmented pipe. They range from two inches to a foot long and are related to the more familiar sea horses of temperate waters. They are sluggish burrowers in coral reefs. As among sea horses, the male gives birth to the young. The eggs are deposited in pouches on the male’s belly where they are carried until they hatch.

_The Varieties of Raven Language_

While “nevermore” apparently is not in the vocabulary of the raven this big black bird of the wilder parts of the country has a considerable variety of sounds nearly as ominous.

Raven “language” has been intensively studied by the noted ornithologist, Dr. Arthur Cleveland Bent. Citing various bird observers, he lists the following calls:

A distinct, hollow, sepulchral laugh, haw-haw-haw-haw, which may be heard at almost any time.

A series of “crawks” sounded while on the wing, interspersed with a musical note that sounds like ge-lick-ge-lee.

A strange call like thing-thung-thung which is similar to the mellow twang of a tuning fork.

Another expression has a metallic, liquid-like quality similar to the song of the red-winged blackbird, although greatly magnified in volume.

Ravens have a large range of notes from the melancholy croaks with which they chiefly are associated to striking imitations of other birds, such as geese and gulls. One of these birds will talk to itself for hours with a curious gargling sound. He becomes so absorbed in his own conversation that it often is not difficult to steal up on him during such a soliloquy.

“The raven,” Dr. Bent observes, “is one of our most sagacious birds—crafty, resourceful, adaptable, and quick to profit by experience. Throughout most of its range it is exceeding shy and wary. It is almost impossible to get within gunshot of one in the open. Yet it knows full well where and when it is safe. About northern villages, where it is appreciated as a scavenger and seldom molested, it is as tame as any barnyard bird.” This is especially true in Greenland where ravens infest American air bases.

Although in the north the raven frequents the seacoast and villages, from Pennsylvania southward it is entirely a mountain bird, usually living above 3,000 feet. From these heights the birds sometimes descend to the valleys, or even the islands along the coast, to forage among the colonies of sea birds. Most of them prefer to dwell among rocks and resort to perpendicular cliffs and to escarpments thrust above forests on the flanks of mountains.

_Worms With Hypodermic Needles_

Despite their microscopic size, nematodes (soil worms), are highly organized animals. They have muscles, quite specialized organs for feeding, a digestive system, a nervous system with a brain, and a well-developed reproductive system. Sexes are clearly differentiated. The creatures have evolved a long way from the primeval worm.

Eggs may be deposited in the soil, or in the plant on which the nematode feeds. In these eggs the immature forms, the larvae, develop and eventually hatch. If appropriate plants are available, they may begin to feed immediately. They develop through several distinct stages. At the end of each of these cycles a moult occurs.

Many of the forms which have been studied closely have a minimum life cycle, from egg to egg-laying female, of several days to several weeks. The maximum duration of life, however, may be much longer, since sexual maturity is not reached until the nematode begins to feed on the living plant. Up to this time it remains in the larval stage and lives on a reserve food supply originally derived from the egg. The time this reserve lasts depends on circumstances. In damp, warm soil the nematode will be very active and use it up in a few weeks. In cool or dry soil the supply lasts much longer, and can extend to many years.

The little worm’s life is a perpetual struggle for existence. It has many enemies in the soil—insects, fungi, and other free-living nematodes. Certain of the soil fungi have “traps” especially designed to catch nematodes. Some of these are shaped like loops which are pulled tight as the worm starts to crawl through. Others are sticky surfaces on which the victims are captured, like flies on flypaper. In either case, the fungus grows into the body of the worm and kills it.

Nevertheless, the nematode population is never in any great danger of extermination. A single female root knot nematode will produce about 300 eggs in a couple of weeks. Allowing four weeks for a generation, and assuming half the offspring are females, this implies a theoretically possible fifty trillion individuals at the end of the four generations of a single summer.

Practically all roots are attacked by some kind of nematode, but many species appear to specialize on one type of plant and will not touch a different variety, even if no other food is available. Plants immune to one species may be highly susceptible to some other. A few kinds of these worms, however, appear to eat almost anything they can find underground.

All the root-eaters have a feeding organ which is much like a hypodermic needle. This is pushed into the tissue and, it is believed, a digestive juice of some sort is injected. This liquifies and partially digests the food. Then the nematode sucks it through the needle into its mouth.

The largest of the nematodes, a parasite of whales, can reach a length of 27 feet. The smallest, a marine form, is a little more than a three-thousandth of an inch long.

_The Fatal Black Widow Spider_

The venom of the dreaded Black Widow spider is approximately fifteen times more potent than that of the rattlesnake. The comparison has been established by determining the amounts of rattlesnake and spider venom necessary to kill rats of the same weight. The extreme toxicity of the spider becomes of considerable significance since it has been reported from every state in the Union and may be increasing in numbers on the edges of cities. Probability of being bitten, however, is slight. The black widow is a timid creature, except towards her natural prey. At the first molestation of her web she retreats quickly to her central nest and does not venture out again for hours. She makes no attempt at defense, to say nothing of aggression. Her reputation is so bad, however, that in some cases pickers have refused to work in vineyards which she infested.

_Plants That are Animated_

Among the curiosities often sold in American stores are so-called “air plants”—plants that will grow on air alone without sunshine or water. This is true, after a fashion. The “plants” actually are dried skeletons of marine animals. They belong to the group which includes the jellyfish, sea anemones and corals. Their skeletons have a striking resemblance to plants.

The species most commonly sold is sea moss or Neptune’s fern, an animal abundant in the North Atlantic, especially in the English channel and the Gulf of Maine. A closely related species, the “squirrel’s tail,” is abundant in the eastern Pacific where its silvery colonies often are washed ashore by storms. Dry beach material of these colonies is easily collected, dyed and sold as Christmas decorations.

“These are colonial forms consisting of thousands of individual animals,” according to the Chicago Museum of Natural History. “Colonies of two species of sea squirrel may be twelve inches or more long. Those of some species may be several feet in length. Usually they are attached to rocks or other substrata by a rootlike base, from which spring the delicate branched stems bearing hundreds of minute polyps.

“Most of these are hydranths (feeding polyps) that capture microscopic organisms. The reproductive polyps are less common, usually larger, and different in shape. The common stem is made up of external non-cellular material, mostly yellowish or brown in color.”

_The Tomato—Cinderella of Vegetables_

A remarkable chapter in the history of agriculture is the story of the tomato which now constitutes one of this country’s major crops. It appears to have first been used as a food by the Aztecs. It was introduced into Spain early in the 16th century and a century later was grown widely in England as an ornamental plant. Not until the next century, however, did it have any standing as a food. It was known as the “love apple” and was considered mildly poisonous. Folks ate one now and then on “dares.”

Then it caught on as a food in Italy and by the start of the 19th century was being grown on a field scale. So far as known, it was absent from the gardens of Colonial America, unless as a rare ornamental plant. Not until the middle of the 19th century was it reintroduced to its native western hemisphere as a food crop. For a long time it acquired no great popularity. A few vines in the family garden were considered enough, since there was no tomato market.

A U. S. Department of Agriculture report calls the tomato “the prodigy of the vegetable world.” Its present success is due in large part to the discovery of vitamins. Although used as a food for little more than a century it now is almost as widely distributed as wheat, a food plant which has been cultivated for at least 5,000 years.

Today the tomato crop covers about a half million acres in the U. S. alone. This crop consists of more than 20,000,000 bushels of fresh tomatoes and more than 300,000 tons of canned products. There are now about 150 known varieties, adapted to all sorts of purposes.

_The Holiest Place on Earth_

The summit of Adam’s Peak in south-central Ceylon, wrapped perpetually in priestly robes of grey clouds, is one of the holy places of the earth. There, through many centuries, the prayers of millions belonging to warring creeds have worn thin the curtain between the effable and the ineffable. It is a shrine of four of the world’s great religions. In the rock is a depression that looks like a giant’s footprint. Hindus believe it was made by snake-haired Siva, the destroyer. Moslems say it is the footprint of the first man, Adam, who was exiled to this mountaintop after he was thrown out of Paradise. Buddhists believe that it could have been made only by the great Gautama. Nestorian Christians maintain that it is a relic of the disciple Thomas, who brought the gospel of Christ into the East. To this spot, braving the road through leech-infested forests below and the perilous ascent along gale-swept ledges, have come generation after generation of devout pilgrims to voice a common prayer in different tongues through different intermediaries.

The pilgrim, standing by the footprint of Adam, looks down upon the forest-covered hills to the eastward. Over all the land spreads the grey shadow of the supernatural. Below him is one of the most imposing spectacles on earth—the middle slopes scarlet with the blossoms of dense forests of gigantic rhododendrons, the deep-blue patches of mountain lakes, and canyons which no human has entered—their mysterious depths hidden by wind-tossed fog. Great waterfalls roar over vine-covered cliffs. Strange sounds arise from jungles of white-stemmed palms. It is a wild land of ghosts and demons watched over by the holy mountains.

In this unearthly country native legend from ancient days has placed, most appropriately, the death valley of the elephants. There, in a pleasant hollow beside a lake of clear water—reached only by a narrow pass with high walled precipices on either side—these animals make their way from all over the island when they feel the chill drowsiness of approaching death. It has been an interminable procession of the doomed since time began. To the stricken old elephant, the coming of death brings an irresistible nostalgia which draws his faltering feet homeward to this mist-shrouded valley piled high with the white bones of his ancestors. It is his haven of rest from the weariness and disillusion of living.

The belief has deep roots in the ancient folk-lore of Ceylon. It has spread all over the East. It is embodied in the Arabian Nights. No man ever has entered this vale of death since Sinbad the Sailor, who was carried there in the trunk of a huge elephant after he had been knocked senseless when the tree in which he was hiding was uprooted by a herd of the animals. Sinbad at last found himself in this valley piled high with bones and knew that he was in the long-sought death place of the elephants.

Another Ceylon elephant cemetery is concealed in a dense forest near the ancient sacred city of Anardhupara. It is so well hidden that no man knows its exact location, although all know that it exists. Unless there are such cemeteries, the natives ask, what becomes of the remains of dead elephants?

The death of the jungle elephant remains a fantastic mystery. No very serious efforts have been made to provide a solution. Remains of these creatures that have died natural deaths seldom have been found, either in Asia or Africa. Yet obviously the great beasts are mortal, subject to various fatal ailments and to the inevitable decay of age. Evidently when one of them feels death approaching it retires to a place of the dead where it quietly breathes its last and adds its bones to those of the vast multitudes of its race that have gone before it into the unknown.

The belief is so strong that there has been a persistent search for these elephant Golgothas for the past century. Such a discovery, especially in Africa, probably would mean inestimable wealth in ivory. But, except for one or two questionable instances cited below, nobody ever has found such a place. Natives sometimes claim to know an approximate location from tradition, although they never have seen it.

Zoologists naturally frown upon the idea because of its very weirdness. They explain that the remains of very few tropical animals ever are found and that the elephant, for all its bulk, need be considered no great exception. Vultures, jackals, hyenas and other carrion eaters soon would tear the flesh from the bones. Insects would bear away the fragments they left. Jungle vegetation rapidly would cover and hide the naked skeleton.

Some credence is given to the native belief by Lieut. Col. Gordon Casserly of the British army. A persistent elephant hunter during years of service in India, he never came upon the carcass or bones of one of these animals which had met a natural death. “The idea of a vast death place of these modern mammoths hidden in the remote recesses of the Himalayas,” he states, “did not seem a far-fetched one to me when I lived in the shadow of those mighty mountains and heard at night the great elephant troops pass by the little outpost that I commanded on the frontier of Bhutan, as they clamber up towards the snow-clad peaks from the forest below.”

The British elephant hunter W. D. M. Bell once thought he had found one of East Africa’s elephant cemeteries in the country north of Lake Rudolph. He had followed an elephant path to a grassy plateau strewn with skulls and other elephant bones, some partially buried. None of the remains, however, were recent. Bell tasted the green water of a nearby pool and found it bitter with natron. The indications were that large numbers of elephants had been driven to this pool to drink during a time of drought and had been poisoned by the water.

Maj. P. H. G. Powell-Cotton tells of finding another spot strewn with bones in the same general region which might answer the specification for an “elephant graveyard.” “Here I was surprised,” he reported, “to find the whole countryside scattered with remains, the fitful sun lighting up glistening bones in every direction. In all my journeyings through elephant country I do not think I have ever come across before a skeleton of one of these beasts for whose death the guides could not account. My guide called this place ‘The-place-where-the-elephants-come-to-die’ and assured me that when the elephants fell sick they would come deliberately for long distances to lay their bones in this spot. I had heard of these cemeteries from Swahili traders who told me they had occasionally found more ivory than they could carry. The place was well known to the Turkana, who regularly visited it to carry off the tusks.”

_The Vanishing Golden Carpet_

The rarest plant in North America, found only four times by botanists, is a ground-hugging desert flower—the gold carpet. The plant appears, on rare occasions, in California’s Death Valley. Its appearance is that of a rosette of yellow leaves, sometimes as much as ten inches in diameter, lying flat on the ground. From this rosette arise innumerable tiny golden yellow blossoms, so that the whole seems like a patch of golden carpet in the brown desert. The reason for its rare occurrence is that its seeds can germinate only after a good rain. Such rains are rare in its habitat.

The plants must spring up within a few days. Ordinarily, even then, they die with the increasing drought before blossoming—thus forming no seeds. In order for them to produce the seeds for another generation there must be another rain following shortly upon the first.

The seeds become buried in the desert soil and, in the course of evolution, have developed the capacity of suspended animation over a number of years. In the old days, it is probable, these seeds retained their fertility only for a single season. Now there may be several years between rains sufficient to spur them to germination, and even longer periods between double rains which will enable them to form seeds.

The strange little plant first was discovered in 1891. There were only two specimens and search failed to reveal any more. Two years later, however, at about the same place another single plant was reported. No others were revealed by an intensive search through the entire area.

In 1931 and 1932 Dr. Frederick V. Coville of the U. S. Department of Agriculture and French Gilman, a California botanist, again made an intensive search but could not find a single plant. They came to the erroneous conclusion that the plant might be native to the mountains, from which occasional seeds were washed down after heavy rains. A few years later Mr. Gilman again took up the search and succeeded in locating the plant in four places. He found 14 individuals altogether and watched their growth carefully. Only three became large enough to flower and produce seed. The others dried up and died when they had only a few leaves and no branches. Later, however, Gilman found many specimens of the gold carpet scattered over low hills in the neighborhood.

These little hills all were whitish in color. This led to the idea that the chemical composition of the soil might have something to do with the appearance of the plants. Analysis, however, showed there was no basis for this assumption.

In the distant past, the gold carpet may have been a very abundant plant, germinating and flowering annually in a reasonably moist climate. Probably a few individuals developed the capacity of producing seed which would remain fertile over a lapse of years. When the climate changed these had a decided advantage over their fellows.

Apparently the gold carpet is a plant in the process of extinction. The continued existence of the species depends on the dormancy of a sufficient number of seeds to carry it over unfavorable years of inadequate, or inappropriately timed second rains. If Death Valley becomes drier and drier and years with suitable double rains become more and more infrequent the vitality of the seeds in the soil eventually will be insufficient to span the long periods when no seeds are produced.

_Evolution of the Bird_

It’s a long call from the birds with teeth that hovered over the strange world of the dying dinosaurs 150,000,000 odd years ago to the chorus of sweet singers whose music opens sleepy eyes on May mornings of the present. The long and devious road can be traced from the grotesque archaeopteryx and archaeornis—nightmare-like and long extinct flying creatures of the dawn—to the living wren and blackbird. But however complicated, the family tree of birds is simple compared to that of the reptiles or the mammals, since avian evolution has been confined within narrower lines.

Up to the time that the monster reptiles were beginning to disappear, it seems probable that all birds had teeth. Gradually, they disappeared as the group advanced into the dawn age of present life forms. First were the ancestral birds—the archaeornithes. They were essentially winged reptiles. Following them came the toothed true birds of the New World, known from very fragmentary fossil records. They included the hesperornis, the hageria and the ichthyornis. Then, representing a long advance, came creatures of the ostrich family, probably the most primitive of living birds. They are true birds but have not reached the typical modern pattern. At the top of the family tree, the highest branch of bird evolution, is the great sub-order of song birds. It includes fifty families ranging from the larks to the finches and buntings.

_Speed Ace of the Air_

The swiftest bird flight ever recorded accurately is in the neighborhood of 175 miles an hour. Ordinary, unhurried flight averages from twenty to forty miles an hour.

The fastest flyer, according to official records, is the California duck hawk whose speed was measured with a stop watch from an airplane. Eagles apparently are much slower.