Part 20

Fortunately nobody is likely to meet this horror of an hallucination-damned maniac’s ravings on a lonely road passing a graveyard at night. It is a mollusk, a close relative of the octopus and the squid but belonging to neither family, which lives in abysses of sub-tropical seas all around the world, far below the depths reached by the most penetrating green rays of the sun. Only its relatively small size and restricted habitat prevent it from being the most fearsome, loathsome creature on this planet.

The “vampire” is a living fossil, survivor out of the demonic seas of 200,000,000 years ago which found shelter from the inexorable scythe with which time mows down demons by retreating further and further into the dark. Imprints of quite similar sea animals, probably denizens of warm, shallow waters, have been found in English rocks.

Up to now about a hundred individuals have been taken from the deep sea, mostly by scientific expeditions. Of these, nearly two-thirds have come from the Atlantic off the Florida coast and near Bermuda. There are several in the Smithsonian collections. The fantastically terrible little mollusk was first taken in the Indian Ocean by Dr. Carl Cuhn of the German Valdavia expedition about 75 years ago. Until quite recently all specimens obtained have been in poor condition and there has been considerable difficulty in classifying them. The job has been complicated by the fact that the vampire apparently undergoes a series of metamorphoses which have been mistaken for different species. During the past ten years, however, they have been studied intensively by Dr. Grace Pickford of the Bingham Oceanographic Laboratory of Yale and their fearsome reality has been established beyond question.

Naturally, since the living animal cannot be observed, essentially little is known of its habits and ways of life. Certainly it is a voracious carnivore like all others of its race and preys upon every other creature of the depths in its size range. It seems to be confined exclusively to a depth of about 1,500 meters. This is the level of the sea where, for some reason oceanographers are unable to fathom, the oxygen content of the water is lowest. It goes up immediately both above and below. The vampire, apparently, cannot stand too much oxygen. Its eggs sink to about 2,000 meters where they reach their suspension level. As soon as the little mollusks hatch they rise to their natural habitat.

The vampire has powerful tentacles but its fin muscles indicate that it is a weak swimmer. It probably lurks in the abysmal darkness for its prey to come within reach of the probing tentacles. Even with its enormous eyes and its many lights it hardly can distinguish moving objects very well and presumably is not particular about what living things it eats. Its usual victims probably are fishes and smaller mollusks. It is unlikely that the creature has many natural enemies it need fear. Unlike the octopuses, its nearest relations, it has no ink sac from which to discharge a black cloud around its body for its own concealment.

_Climbing and Flying Frogs_

A family of frogs that climb trees, burrow and are learning to fly are the tree frogs of Mexican tropical forests. Various members of the family are at different stages in their physical adaptation to tree life. They constitute a striking example of evolution at work as a race struggles to shake itself free from one environment and conquer another despite considerable odds.

The ends of the fingers and toes of those frogs are provided with adhesive disks by means of which the animals are able to obtain a firm foothold on relatively smooth surfaces. These disks are used mainly for climbing, or for clinging to foliage and limbs when jumping. One species is both a climber and burrower. It is an extremely timid little creature and a poor climber, but it buries itself deeply in tree mosses. Another species, which seems as much as home on the ground as in the trees, deposits its eggs on the upper surfaces of leaves overhanging the water. The tadpoles, which must return to the water for their metamorphosis into frogs, simply drop off the leaves after they leave the eggs. Perhaps the most peculiar of the family is the marsupial frog, Gastrotheca, all of whose young are sheltered in a pouch on the back of the female. Some of the family lay their eggs in nests of froth attached to leaves.

One remarkable species seems to be developing the ability to fly. Its hind limbs are elongated for jumping and it has been known to leap and alight without injury from a height of 140 feet. When handled it exudes a poisonous, milky fluid which coagulates instantly, sticking to the fingers in a disagreeable way. It has a strong odor, like that of peaches, which causes the inside of the nose to itch. Experiments are described in which this animal was dropped from the top of a high water tower. It immediately spread out its limbs and, instead of dropping vertically, sailed slowly downward and landed uninjured on the ground about 90 feet away. Apparently it was able to get the best of gravity after a drop of about twelve feet. From that point on, there was no apparent acceleration in the speed of descent. A state of equilibrium was reached. Whenever one of these frogs was thrown in the air it invariably managed, after a violent struggle, to establish itself in a balanced position which it could maintain, apparently without effort, while it glided to the ground.

Within certain limits these tree frogs can change their color so that their bodies will blend more perfectly with their surroundings. One of the most widely distributed Mexican species seems to have an exceptional color range. This particular creature also is notable for its elusiveness. It exists in countless numbers, yet an explorer may hunt for weeks without encountering a single one. Such was the experience of the German naturalist, Hans Gadow. While wandering along the edge of the forest he heard what seemed to be the noise of a sawmill in the distance. As he came nearer this sound changed into a roar like that of steam escaping from many boilers, mingled with the sharp and piercing scream of saws. It came from a meadow containing a shallow rainwater pool in which were tens of thousands of large, green tree frogs. Gadow calculated that in this pool, about thirty yards square, and in the immediate neighborhood, were more than 45,000 of the creatures. The water of the pool was covered with their spawn—a minimum of 100,000,000 eggs. The next morning there was not a single frog in sight. The water had evaporated during the night and the eggs were left to be cooked by the sun.

One of the most curious of these creatures is the banana frog, whose habitat often is the upper side of a banana leaf. It is an extremely elusive creature whose color undergoes considerable change without being specifically responsive, so far has been observed, to the intensity of light. Another curious member of the family wraps its eggs in foamy lather and suspends the whole mass between leaves or blades of grass over water in such a manner that the next heavy rain washes the developing eggs or tadpoles into it. It is necessary that the tadpole stage be passed in water. Development of means to bring this about was necessary before the family could conquer a tree environment.

Another little frog spends its entire life in the leaf-formed cup of a bromelia, a plant somewhat similar in appearance to a small century plant, which grows on the branches of trees where its roots get a precarious foothold. During the rainy season this cup becomes filled with water. There the frog lays its eggs, which hatch as pollywogs.

Truly demonic are fantastic horned frogs of Brazil which devour other amphibians and small mammals. The largest of them do not hesitate to defy a human being in the mountain rain forests, their chief habitat. They are six inches long or longer and as broad as long. Some have horns on their eyelids and the tips of their noses. All have enormous mouths, so that a mouse can be swallowed quite easily. When excited they inflate their bodies like balloons and utter bull-like bellows. At other times they are heard to cry like infants.

The horns probably serve no other purpose than to add to the ferocious appearance of the animals. They are just hardened extensions of the skin, entirely too soft to be of any value in combat. All species of horned frogs are rare in collections. They seldom are seen because of their secluded habitat and their clever camouflage. They throw loose dirt over their damp bodies until they become practically invisible.

Rarest of the family are the pigmy horned frogs which have horns on both eyelids and the tip of the nose, as well as a fringe of horns around the eyes. They are beautifully marked animals.

_Mad Dog Cycles_

There may be mad dog cycles. Dogs are much more vicious in June than in the so-called “dog-days” season of July and August.

The tiny poodle and the pekingese share with the big German police dog and the Italian bull rank among the 10 most vicious of domestic canines. These are some of the conclusions reached by Dr. Robert Oleson of the U. S. Public Health Service on the basis of data about dogs in the metropolitan New York area for 27 years.

During this period, Dr. Oleson’s study shows there were two 5-year peaks in rabies, from 1911 to 1915, inclusive, and from 1926 to 1930. During the first period the annual average of bites diagnosed as made by rabies-infected animals was 233, compared with only an average of 78 for the previous three years for which records were available. There followed a period of 10 years during which the number of rabies cases diagnosed in biting dogs averaged only 43 a year. Starting with 1926 the curve leaped up again and in the next five years there was an average of 288 cases a year. Then came another rapid decline.

Apparently the number of rabies cases has no relation to the number of bites. These remained practically stationary at an average of about 3,500 from 1908 to 1926. There was a sudden jump to more than 7,000 cases in 1925, just before the start of the second rabies peak. But since 1930 the number of bites reported has continued to go up, in the face of rigid muzzling restrictions, until it has reached the alarming figure of 20,000. At the same time the number of rabies cases rapidly has gone down.

The same tendency toward the mad dog cycle has been noted in several European countries. It may be due to an inexplicable waxing and waning of the virulency of the rabies virus. During the peak years extraordinary efforts were made to impound all unlicensed dogs, and the decline of the waves may have been due to the lessening of the number of potential rabies carriers by this means.

Contrary to general belief, dogs are getting better tempered rapidly during dog days. The high peak of the year in bites is reached about the middle of June. Then comes a very sharp drop, which continues steadily as colder weather comes on.

No breed of dogs is entirely free from the biting tendency, but some are much more prone to it than others. The mongrel doesn’t rank among the really vicious dogs and pedigree counts for nothing. The 10 breeds, in the order of frequency of their reported bites, are: German police, chow, poodle, Italian bull, fox terrier, crossed chow, airedale, pekingese and crossed German police dog.

_The Amazing Survival of the Opossum_

The opossum, sole survivor in the New World of a primitive and very ancient family, represents an overlooked principle in evolution—survival by endurance.

How this clumsy, persecuted animal has endured through millions of generations in the midst of savage and hungry foes is the subject of a revealing study by Dr. J. D. Black of the University of Kansas.

Dr. Black examined closely the skeletons of 95 opossums in the university museum—all killed in the immediate vicinity. Thirty-nine of them gave evidence of broken bones that had completely healed. One specimen had suffered, and recovered from, breaks of both scapulae, 11 ribs, two broken in three places, and a badly injured spine. Still another gave evidence of having suffered at the same time fractures of the jaw, the scapulae, and nine ribs. Many showed evidence of ribs and scapulae broken in several places. The ability to survive such severe injuries—they would be fatal in any other animal either in themselves or because the crippled condition resulting from them would make a creature an easy prey to its enemies—illustrates the importance of the opossum’s practice of playing dead.

The opossum represents an important stage in the evolution of mammals—that of the marsupials, or pouch bearers. They presumably were quite widely distributed over the earth at one time, before the emergence of the placental type of mammals to which the human race belongs, together with almost all other warm-blooded animals. They may be the ancestors of the placentals or they may represent a different line of development from the ancestral reptiles. In any event, they are considerably nearer the type of those ancient egg-laying reptiles. They are just a step beyond the egg-laying stage.

When the placentals arose the marsupials quickly disappeared from most of the earth. They were not so well adapted for survival in conflict with the more advanced, efficient type of animal. Only in Australia did they find a haven. With a single exception, they were the only mammals there when the continent first was discovered by white men. This has led to the speculation that Australia was cut off from the rest of the world before the placental races were evolved, or before they had attained such efficiency in the ways of life as to enable them to survive. There the marsupials, without competition, were able to survive and differentiate into rich fauna of the continent—of which the kangaroos are considered the most characteristic animals.

The one exception was in North and South America in the person of the lowly opossum. All the meat-eating animals which arose around the creature fed upon it if they could catch it. It was not very efficient in getting away from a pursuer. It developed no effective armor, like the shell of the armadillo or the quills of the porcupine, with which other weak animals managed to survive. It was not even very efficient at hiding. When man arrived on the scene with his bows and his guns, its last havens, the treetops, lost their small measure of security.

All the cards were stacked against the survival of the opossum, but it developed a means of its own to keep a tenacious hold on life while far more efficient creatures—beset with new enemies and changing climates—were forced to give up. The great mammoth herds, lords of the earth for a million years, disappeared. The ferocious saber-tooth tiger and the great cave bear expired by the roadside in the race of evolution. But the poor opossum had discovered the important principle that the meek shall inherit the earth—or, at least, be allowed to live in it. It became the great pain endurer and lived by submitting and gritting its teeth. It didn’t fight nor hide. It merely suffered and learned how to endure suffering. This supreme ability of the opossum to recover from injuries goes a long way toward explaining its survival.

The opossum thus appears to be the prototype of a familiar class of men and women. They are frequently encountered. As children they have almost every conceivable disease. Their adolescence is a continuous succession of broken bones. Their parents despair of raising them. When they come to adult life the story is much the same. They suffer a constant stream of misfortunes, physical and otherwise. Physicians are amazed at their recoveries. And they often survive into the 80s and 90s of life while the healthy, fortunate individuals with whom they started out are left behind in the prime of life—victims of pneumonia, heart disease or accident. When the latter die the news comes as a surprise to their acquaintances who cannot understand how the strong die and the weak survive. They ponder over the paradox that strength is weakness and weakness strength. The ancient opossum might explain that paradox if it had the means to express itself.

_Mammal Prototypes of the “Mermaid”_

The prototypes of the “mermaids” of legend are among the least known of all animals to naturalists because of their underwater habitat and their secretive habits. They are the manatees of the Caribbean region and the dugongs of the Indian Ocean. They constitute the only remaining species of the serenia, or moon creatures, distant relatives of the elephant. Both have a somewhat human facial appearance. They feed standing upright in the water, their flippers held out before them like arms. Sometimes the females hold their calves in these flippers. Seen from a distance, they have a curiously human appearance, which may account for the many reports of mermaids and mermen.

This is especially true of the dugong—a creature of the open sea, with a white, almost hairless body. It is extremely secretive and has almost never been captured alive. When one is washed ashore or caught in a fisher’s net it causes superstitious fear among the natives. The manatees are not so human in appearance and are much better known.

The creatures seldom make their appearance above water in daylight. They prefer to gaze in the moonlight, and this has added to their humanlike appearance which has given rise to the mermaid legends.

One of the few persons to study the animal at close range, O. W. Barrett, an American explorer, tells us the following concerning the manatee:

“The animal still is fairly common in most fresh-water bayous, lagoons and rivers along the east coast of Nicaragua. One of the best-known herds on the Caribbean Coast inhabits the Indio River, just north of Greytown, Nicaragua. Estimates of its number vary from a few score to several hundred. The herd apparently is stationary there and does not increase or decrease to any notable degree from year to year, although the natives take a heavy toll....

“A manatee can remain under water from 20 to 30 minutes when frightened. During the daytime the slightest unusual noise, like rain falling on a tin pail or the spitting of the hunter, is sufficient to keep the whole herd submerged for hours, yet while they are grazing the hunter may go up and slap them on the back unnoticed.

“Families consisting of a bull, a cow, and one or two calves usually ... merge into a herd of from 10 to 50 or more individuals living in a certain stretch of river, concentrating during the day and scattering at night. They generally graze at night, although a few individuals may be seen feeding in broad daylight. The body is held nearly vertical while grazing. The head is held well out of water, while the armlike flippers poke the grass toward the mouth. The noise made by the flapping of the huge upper lip and the crunching of the large teeth can be heard distinctly 200 yards or more away. The sound is much like that of horses grazing in a pasture. Adult manatees appear to average somewhere between 8 and 10 feet in length. Some—old females, presumably—may reach 12 feet.”

A much more seclusive animal is the true “mermaid” of legend—the dugong of the open ocean. Unlike the manatee, it is a creature of the sea and seldom ventures into the fresh-water rivers and lagoons. Few naturalists ever have actually seen one of the creatures. Mr. Barrett’s first acquaintance with the creature came in Mozambique, Portuguese East Africa, when some native fishermen caught in their net what they described as a “white porpoise.” They were terrified and gladly presented their catch to an Italian blacksmith. This man crudely embalmed the animal, placed it in a rough coffin and freighted it to Johannesburg, where he rented a show room and made a fortune exhibiting “the only genuine mermaid—half fish, half human.”

For many years mariners in the Indian Ocean and the Red Sea have told of seeing objects resembling women standing waist high on the surface. Zoologists of the Middle Ages described a “bishop fish” which had been seen standing with outstretched arms, supposedly blessing the waters. In nearly every case, it seems likely, the objects were strange water animals—the dugongs. They have a curious resemblance to human beings, especially naked women, when seen from a distance.

Nearly all mermaid stories have originated in water where dugongs are abundant. Spanish and Portuguese sailors, the first Europeans to encounter the animal, called it the “woman fish.” The creature is best known to Malagasy fishermen of Madagascar who, while they prize its flesh highly, attribute to it human qualities and affinities. After capturing one the fisherman must perform various religious rites and before he is allowed to sell the flesh at a public market he must take an oath that there have been no unnatural relations between himself and his mermaid victim.

The female’s breasts are roughly in about the position of those of women. She has the habit of rising about halfway out of the water and sometimes has been described as holding her baby in her flippers. Little is known of the life history and habits of the dugong. It is a creature of the shallow sea which never has survived long in captivity. It seems to share with the elephant and with man the faculty of shedding tears when it is in trouble or pain. One which was kept for several months in the Colombo zoo in Ceylon constantly was weeping. Malagasy fishermen used to torture the animals in order to collect the tears, which they sold as love charms.

Another extant member of the “mermaid” family is the manatee, found on both sides of the Atlantic in the warm, fresh water rivers of Africa and South America. Although never mistaken for a human, it is accorded considerable superstitious regard. The Kalaboi of Nigeria regard it as a sacred animal and the incarnation of a human soul. If a fisherman kills one, by accident or otherwise, he must undergo an elaborate cleansing ceremony which involves offerings before images of his ancestors and remaining indoors for three days. During this period he is rubbed from head to foot with a yellow pigment by women of his family. While the purgative rites are in progress the women sing at dawn and dusk. On the third day there is a feast on the meat, but a bit must be given to every household in the village to lay upon the shrines of ancestors.

Both manatee and dugong, and formerly the extinct sea cow of Bering Sea, are probably the closest living relatives of the elephant. They have similar brain and heart structure. The molar teeth of the mermaid family are like those of early elephants. The male dugong has tusks. There also is a great extension of the upper lip which overlaps the side of the mouth—a start in the direction of a trunk.

The next nearest relatives of the elephants are the hyraces, or conies, of Africa and Syria, best known in the form of expensive fur coats. They look and act like rabbits. A Hebrew prophet made them symbolic of timidity. Only a taxonomist would suspect these little creatures could claim any kinship to the largest of land mammals.

_Limbless Lizards and Glass Snakes_