Part 29

From this protrusion a sticky acid is exuded. In rare instance it may be spurted a short distance—an inch or less. These soldiers fight battles to the death with war-like ants which invade their nests. The termite warrior rams with his nose-like organ the so-called “pedicle” of the ant, the narrowest part of its body, smearing it with the liquid. This never has been completely analyzed. It is a powerful acid, but is not the well-known formic acid exuded by ants. It has strong corrosive properties when applied to metals. It has a pungent odor which, however, is characteristic of all termites and the ancestral cockroaches.

Between ants and termites there is perpetual war. Army ants, especially, try to raid termite nests to feed on the young whenever they can find any crack in the walls through which they can squeeze their bodies. But when there is any break in the nest the termite soldiers immediately arrange themselves in a circle around the opening while workers bring up little slabs of earth from the interior to patch the wall.

Most common of the Barro Colorado species are the amitermes which build hemisphere-shaped red mounds about two feet in diameter. These are made of tiny particles of earth which have passed through the alimentary tracts of the insects where they are coated with a cement-like material. Such a nest is impervious to water. It is so sturdy that a heavy man can jump up and down on it without breaking the roof. It cannot be broken open with a machete.

Another common species build the so-called “niggerhead” nests, about the size of footballs, on fence posts and trees,—especially dead trees whose stumps protrude out of Gatun Lake. These nests also are extremely sturdy. They are made of a mixture of earth grains and finely digested wood. From such a nest numerous runways traverse the trunk, sometimes connecting with smaller colonial “niggerheads.”

Oyster Oddities

An oyster can change its sex several times during its life. This has been determined by Dr. Paul Galtsoff of the U. S. Fish and Wildlife Service by observing an experimental colony. In the first year 8% of the males changed to females and 13% of the females became males. In the second year 11% of the males changed sex and 12% of the females. One sex change, Dr. Galtsoff found, makes the same individual more likely to undergo another.

A single Pacific coast oyster produces approximately 10,000,000,000 descendants a year. If all survived in five generations they would constitute a mass eight times the size of the world.

Clams and oysters appear to be about the most stupid animals in creation. Actually each has three “brains,” or nerve ganglia. One controls the feeding apparatus, another the viscera, and a third the utilization of oxygen.

The World’s Biggest Sneeze

The sneeze of the elephant has been described as “like the bursting of a boiler of considerable size.” When the elephant feels the onset of one of these titanic eruptions it appears to realize that a momentous event is about to take place. It becomes extremely restless and is seemingly unable to stand still for a moment. The sneeze is preceded by a tremendous, wall-shaking bellow.

Although elephants are subject to frequent colds the sneeze is a rare phenomenon. For this reason it is regarded as a good luck sign, especially among Moslems of India, who gather around and wait patiently for the event. When it starts they bow their heads and pray for the realization of their wishes.

The Luminescent Ctenophores

There are windless nights when Caribbean waters seem like fields of green fireflies. This is due to vast numbers of luminescent ctenophores or comb-bearers. One the most abundant and least known forms of animal life, they are also among the most delicate. Although they are related to the planarian worm and the jelly fish, they are quite unique.

Superficially they seem little more than animate bags of water with skins thinner than the most delicate tissue paper. They abound in staggering numbers over most of the world. One of the most familiar types is the American mnemiopsis. On calm summer days the amber green species sometimes covers completely thousands of square yards of sea—like a raft formed of millions of individuals floating just below the surface. A classic ground for this phenomenon is Narragansett Bay.

Like the rest of its race, this ctenophore is like a fragment of moonlight on the sea. It is so fragile that the slightest current of water in its neighborhood is sufficient to tear it to bits. It is about as elusive as moonlight. When grasped gently the jelly-like substance slides through the fingers. Taken in a net and placed in salt water it vanishes completely on the way from boat to laboratory. Intact specimens are almost unknown in scientific collections.

Ordinarily they live at considerable depths in the zone of absolute calm where all wave movement ceases. Great hordes rise to be the surface only on nights when the surface of the ocean is like a sheet of glass.

They are among the loveliest of all sea creatures. The delicacy of their coloring is that of spring arbutus or anemone. Their presence is indicated chiefly by the brilliant flashes of rainbow colors as they pass a few inches below the surface.

The majority are pear-shaped. Giant of the race is Venus' girdle, best known in the Mediterranean but found in most sub-tropical seas and sometimes swept as far north as the coast of New England. It is an undulating, iridescent ribbon as much as five feet long and two inches wide. The mnemiopsis of southern New England waters is ball-shaped with a diameter of about four inches.

Ctenophores are most varied in the Bay of Naples; there 18 species have been identified. There are 14 species now known in the Caribbean. In absolute numbers, however, the fragile creatures are most abundant in North Atlantic and sub-Arctic waters where, because of ordinarily rough seas, they seldom are seen. There they constitute one of the major menaces of the cod fisheries. Despite their fragility they are vicious little animals, devouring cod eggs and fry in incalculable numbers.

Each living water bag has a slit-like mouth on top and what apparently is a sense organ of some kind on the bottom. The minute, struggling prey are seized in two pincer-like tentacles and pushed into the mouth. They are digested quickly by the juices in the water sack in which float about whatever vital organs the Ctenophore possesses.

The ctenophores are by no means aberrant jellyfish, which they resemble only in the extreme tenuousness of their bodies. They have no umbrellas and no stinging cells. Two forms are known which have flattened bodies like planarian worms and which creep on the sea floor. Because of various similarities in the development of both creatures some zoologists believe they are immediate descendants of a unknown common ancestor.

The function of their weird green luminescence is unknown. It would seem of questionable value in attracting prey and it is difficult to imagine that these most fragile and evanescent of earth’s creatures have any sort of love life. Nevertheless lightmaking seems to constitute a purposeful part of their activities.

The Forest That Time Forgot

Knee-high red and pink ferns fill the jungle hollow. Around them are green leaves covered with parallel white lines in sets of five with dots on the lines which look like notes of music. These leaves are known as “music paper.” There is no record that anybody has tried to play the tunes nature has written on them.

Mixed with them are “sandpaper leaves” with surfaces so rough that they are used locally for the same purpose as sheets of sandpaper elsewhere. Sinister hangman’s ropes swing, as if awaiting their victims, from branches along the jungle paths.

Such are a few random notes from a cloudland jungle—in many ways like a forest of prehistoric days—in Venezuela’s Henry Pittier national forest. Here flourishes the giant tree fern, most characteristic tree of the vast ancient forests from which coal deposits were formed. In the tree fern fronds lurk worms and amphibians not vastly different from the tree creatures of the Devonian geological area.

This is a forest of the central tropics. Paradoxically it is also, when seen from a little distance, a New England forest of late September with groves of straight, white-trunked palm trees which look like birches and patches of flame color in the treetops which look like maple leaves starting to put on their autumn coloring. The temperature, in fact, is about that of a warm Autumn day in New England, especially as dusk comes and a white veil of mist rolls over the mountaintops from the sea.

The patches of flame color which look like maple leaves are orange and red blossoms of the gallito or “cock flowers,” so called because the bloom resembles so much the body of a miniature rooster. The gallito appears high in the treetops. It is about the most abundant and conspicuous flower of the cloud jungle. It grows on big, grey-trunked trees whose bark looks like rough-woven linen. Each blooming tree is filled with brilliantly colored humming birds and red and green parrots.