to tear off and eat only the ovaries and stamens of blossoming plants.
“These are certainly not isolated acts,” says a Pacific Science Board
report, “but ones perfected by practice and perhaps instinct. The
crabs probably decimate the flora, feeding particularly on tender
seedlings. They largely are responsible for the paucity of different
kinds of plants on some islands. The seeds of any new kinds of
plants washing to its shores are subject to their inspection and,
if palatable, sacrificed to their appetite. The foreign plants now
being introduced as seeds and seedlings must not only surmount the
drastic condition of drought and salinity but also the hurdle of these
voracious animals.”
In the spring the females carry their numerous maroon colored eggs
attached to their abdomens. When do they return to the ocean to allow
these eggs to hatch their free-swimming larvae that resemble so closely
the shrimp-like ancestor of all hermit crabs? Where do they throw off
the hard, non-expanding shells they have requisitioned as they increase
in size, in burrows on land or in the ocean? How, with gills adapted
for respiration in water, have they perfected respiration on land?
Questions such as these are still unanswered.
_The Ferocious Centipede_
“Natives of Brazil call the centipede the ambua. These creatures of a
thousand legs, some of which are more than a foot long, bend as they
crawl along and are reckoned very poisonous. In their going it is
observable that on each side of their bodies every leg has its motion,
one regularly after the other; being numerous, their legs have a kind
of undulation and thereby communicate to the body a swifter progression
than one would imagine where so many short feet are to take so many
short steps that follow one another, rolling on like the waves of the
sea.”
The eighteenth century British naturalist Charles Owen was not alone in
considering the millipedes and centipedes as kinds of snakes; nor in
being confused, as naturalists still are, at their curious, complicated
way of moving. There had been highly exaggerated reports. The Spaniard
Ulloa, Columbus' gold assayer, described some centipedes he saw on the
northern coast of South America as a yard long and six inches wide.
Their bite, he contended, was fatal.
“In the Kubbo-Kale valley,” reported British naturalist H. S. Wood
in 1935, “I saw a centipede ten inches long. Its general color was
electric blue with bright coral red fangs. It was the most terrible
thing I have seen in my tramps through the forest.” Wood was stung by
one of these Indian centipedes; he described the sensation as “exactly
like that of a third degree burn.”
These animals are neither snakes, insects nor worms. They constitute an
independent and intermediate order of animal life. They are considered
a little nearer to the spiders than to true insects. They have retained
the ways of life of the ancestral worm.
Most of the centipedes are active, ferocious, flesh-eating animals.
Their poison fangs are deadly to their normal prey—earthworms and
insects. Some of the larger species do not hesitate to attack lizards
and small mice. A bite, however painful, probably never is fatal to
a human. All are land animals which creep or crawl under logs and
bark. They usually remain in seclusion during the day but come out of
their retreats at night when they wander over the ground and attract
attention to themselves by their phosphorescence. A few have been
described as sea dwellers but these do not actually live in the water.
They crawl along the shore and are submerged by each tide. Some or
completely blind, others have many eyes.
The centipedes are among the most repulsive of all animals, yet there
are accounts of South American Indian children who drag very large ones
out of the earth and eat them. Religious fanatics among North African
Arabs swallow them alive as proof of their supernatural powers.
Tropical America has many varieties with varied and curious habits,
like the Nicaraguan species described by Thomas Belt:
“Among the centipedes was one which had a singular method of securing
prey. It is about three inches long and sluggish in its movements but
from its tubular mouth it is able to discharge a viscid fluid to a
distance of about three inches, which stiffens with exposure to the air
to the consistency of a spider’s web, but stronger. With this it can
envelope and capture its prey, just as a fowler throws his net over a
bird.
“Some of the other centipedes have phosphorescent spots in the head,
which shine brightly at night, casting a greenish light for a little
distance in front of them. I think these lights may serve to dazzle or
allure the insects on which they prey.”
Centipedes have been observed attacking earthworms. One may grapple
with its victim for several hours before killing it. Then it sucks the
blood.
A fairly familiar visitor in the southern United States is a house
centipede which thrives in damp basements and sometimes invades ground
floors. It is a wormlike creature, about an inch long, with fifteen
pairs of long legs. In the female the last pair are twice as long as
the rest of the body. The animal is yellowish grey with white bands on
its legs. It is poisonous, but its jaws are weak and it seldom bites
human beings. Despite the evil reputation of its race, this centipede
should be a welcome guest for it feeds on cockroaches, flies, spiders,
moths, and other domestic pests. It is a fast runner but often stops
suddenly, remains absolutely motionless for a moment, and then darts
for concealment.
_The Plant That Makes Men Dumb_
A plant now being cultivated in the newly established botanical garden
of the University of Caracas may prove to be nature’s greatest boon to
pestered husbands and harassed mothers. It is described only under the
popular Spanish name of “planta del mudo.” It looks like sugar cane.
According to reliable reports anybody who chews the stem is stricken
dumb for 48 hours.
Other curiosities of the garden include a plant which allegedly can
stimulate hair growth on bald heads and a bush whose blossoms open
snow-white in the morning and turn red at noon. Here also blooms the
exotic “Queen of Night,” a climbing cactus with a white flower five
inches in diameter which opens at sunset and closes at sunrise.
_The Scourge of the Earth: Locusts_
From the days of the Hebrews prophets a visitation of locusts has been
considered one of the plagues of God. A migration of millions of these
grasshopper-like insects in clouds obscuring the sun leaves behind a
countryside devastated as though by fire. In flight they sound like a
forest fire being spread by a brisk wind. Whenever they come to earth
areas of hundreds of square yards almost immediately are denuded of
everything green.
In history their raids have been associated chiefly with the Near East.
Quite similar creatures have caused far-reaching destruction over most
of the world including the United States.
The last such phenomenon was about 1880. Since then grasshoppers have
hopped, not flown. There have been some great invasions, but the
insects have moved along the ground where it is easier to combat them.
The reason for the transformation was found a few years ago by
entomologists. Hopping grasshoppers are changed into flying
grasshoppers by heat and hunger. Grown in test cages at high
temperatures and deprived of succulent green food, the insects acquired
longer wings, became slimmer, and took on brighter colors.
It apparently is a curious provision of nature to preserve the
grasshopper race. When on the edge of perishing, they are supplied with
wings to carry them to green pastures a few hundred miles away. Lately
there has been some indication that those in the western United States
might again enter the flying phase in the near future. During the great
drought of the early thirties there was a stimulus almost sufficient to
make them undergo the complete transformation.
At present there seems little prospect that there will be another
flying cloud in this part of the world. By planting cultivated crops
on land formerly covered by grass, man provides good egg-laying grounds
and plenty of green food.
Adequate information still is lacking on what makes grasshoppers
increase and decrease. Also a mystery is the mechanism by which the
harmless solitary phase is transformed into the dangerous gregarious
phase. Several types occur in both phases and each can change itself
into the other, altering their habits so that they attack in mass
rather than as individuals.
During the late 1870s the flying clouds caused terror all over the
world. In parts of Minnesota where the locusts landed they covered the
ground three inches thick. Crops were destroyed throughout the prairie
states.
The most remarkable incident was reported from Russia in 1878:
“A detachment of Gen. Lazeroff’s expedition against the Turcomans met
with a curious misadventure near the Georgian town of Elizavetopol. A
few versts from the town the soldiers encountered an army of locusts
about 20 miles long and broad in proportion. The officer in charge did
not like to turn back, repelled by mere insects. The soldiers soon
were surrounded. The locusts appear to have mistaken them for trees
and swarmed by the thousands around them—crawling over their bodies,
lodging themselves in their helmets, penetrating their clothes and
knapsacks, filling the barrels of their rifles and boring into their
ears and noses.
“The commander gave the order for the troops to push on the
double-quick for Elizavetopol, but the road was so blocked that the
soldiers became frightened and, after they wavered a few minutes, a
stampede took place. Led by a non-commissioned officer who had espied a
village a short way from the road, the troops dashed across the fields,
slipping about on the crushed and greasy bodies as if on ice. They
were detained prisoners by the insects for 45 hours, and on the way to
Elizavetopol found every blade of grass and green leaf destroyed.”
That same year a cross-continental train was held up for three hours
near Reno, Nevada, by a host of locusts that covered the rails for
several miles.
_Trees Can Grow Smaller_
Trees change size from hour to hour. The circumference of a tree trunk
gets bigger and smaller with unpredictable perversity. For light on
this phenomenon the world is indebted to Dr. John A. Small of Rutgers
University.
About a decade ago tree scientists were provided with an instrument
which could measure continuously the radial growth of a tree with an
accuracy of a thousandth of an inch. With such an instrument it seemed
plausible that it would be possible to tell just how much a tree had
grown in a single day and its rates of growth in different seasons.
A lot of the conclusions reached in this connection must now be
discarded. The circumference of a tree certainly changes but not in a
straight line. It may be bigger one day, smaller the next.
Dr. Small’s experiments were carried out with the white ash. He found
that circumference changes followed yearly, monthly and even daily
rhythms but the changes in the same tree might vary by as much as
200 percent when measurements were made at different times. Daily
variations have shown a tendency to reach maximum readings about 6:30
a.m. and sink to minimum in the late afternoon or early evening.
Eccentric jumps and drops can be found almost any time.
_Underworld Cities_
Seventeen-year locusts build great subterranean “cities” during their
long sojourn in the earth’s depths. The years underground are by no
means a resting period—an episode of being buried alive. All the time
the young locusts, in various metamorphoses, are busy building and
eating. The eggs of the strange insects are laid during a few weeks
late in summer inside twigs. From these eggs come minute nymphs, which
at once make their way into the ground. There they shed their shells
and grow rapidly. Their food is juice sucked from roots. They make
successive mud dwellings attached to these roots. The largest observed
in the eastern United States were eighteen inches below the surface.
Each was a rough ball of earth about two inches long and three-fourths
of an inch wide. The ball is lined on the inside by smooth mud and
contains only one nymph. Every time an individual moults and grows
larger it must make a new house.
When they emerge from the last of their feeding chambers, the locusts
dig rapidly upward and construct a somewhat different type of dwelling
some inches below the surface. These are two-chambered, with upper and
lower rooms connected by tunnels five to ten inches long. These are
so ingeniously constructed, according to Dr. E. A. Andrews of Johns
Hopkins University, that they provide “the advantage of safety along
with quick access to the surface when the proper time comes. In the
shaft the nymph climbs close to the surface or falls rapidly to the
bottom to escape attacks. The lining of the shaft is smooth mud a few
millimeters thick. The shafts are by no means always straight or of
uniform diameter, but may be sinuous and present swollen regions.” In
one area examined he found at the topsoil was such a mass of small
stones and roots that the insects must actually have cut their way
through roots. Large obstacles often were avoided by a change in
direction.
“The chief implements used in making cavities in the earth”, according
to Dr. Andrews' report, “are the big first legs. Here, as in other
legs, the end segment is used chiefly in walking and may be folded
down when not needed. The second segment from the tip is used to pick
off particles of earth. The third segment is the largest and, like a
powerful thumb, acts with the opposing second segment as a forceps to
pick up pellets of earth and small stones. The minute particles picked
loose from the earth are raked together by the tip segment to make a
pellet, which the forceps can carry or shove into the walls of the
cavity. However, all parts of the body may come into use, for the hind
legs and the abdomen may help shove earth aside and the head may carry
earth plastered upon it. In vertical tunnels the animal braces its legs
against the sides and, if disturbed, relaxes and drops down.”
The last dwelling is large enough for the nymph to turn around
inside and usually has a flattened floor. The top comes quite close
to the surface without actually breaking through, leaving only a
few millimeters of earth through which the insect must dig when the
transmutation to an adult locust takes place. Examination of many
of these tubular dwellings shows that there are no interconnections
between them. Each has its own individual exit and along its course
avoids contact with other chambers, although they often are very close
together. This last home of the locust, before it emerges from the
everlasting darkness to the world of light and quick death which is its
pre-ordained destiny, is not necessarily restricted to the earth but
may be contained above the surface. Aerial extensions may, in fact,
be abundant and are in the form of turrets, towers, cones, chimneys,
huts and adobe houses. The walls are of dense mud, not natural soil.
Externally they are made of tiny mud pellets, but lined internally with
the same smooth layer found in the underground dwellings.
_Plants That Create Mirages_
An explorer in the desolate heights of the Santa Marta mountains in
northeastern Colombia, fog-wrapped and 10,000 feet above sea level, may
see a flock of sheep grazing placidly among rocks ahead of him. Then,
looking the other way, he may see an assembly of cowled, robed priests,
apparently in the midst of some weird ecclesiastical ceremony. But when
he reaches the places where he thought he saw these things there are
neither sheep nor priests. He finds instead two strange varieties of
the aster family, both among the real curiosities of the plant kingdom.
The vegetable sheep are bushy plants which grow on nearly barren ground
near the mountain tops. The individual plant consists of thickly
branched stems, about the size of a human finger, bearing many layers
of leaves covered with wool-like hairs. Sometimes these leaves are so
thick that the point of a pencil cannot be thrust through them. Some of
the plants may be as large as a living-room sofa.
The extreme compactness of these plants and their dense covering of
hairs is an adaptation to the hostile conditions under which they must
live. The habitat consists of rocky slopes where the hot, dry winds
of summer and the snows, low temperature and violent gales of winter
expose them to a perpetual alternation of desert and Arctic conditions.
In the same general region are the monk plants, belonging to a
different family, who have responded in the same way to similar
conditions. Seen from a distance on a mountainside, especially
through a light fog, a patch of these plants looks decidedly like a
congregation of several hundred priests.
The vegetable sheep also are found in New Zealand, but there are no
known intermediaries between the closely similar species growing on
opposite sides of the earth.
_The Octopus Worm: Evolution’s Mystery_
Worms that give birth to their own grandchildren, animals that have
no digestive, muscular, nervous, glandular or excretory organs—such
paradoxical creatures are the “dicyemid mosozoans”, tiny worms that
live inside octopuses. These little worms are among the most curious
living things in nature. It is quite uncertain whether they are a step
upward in evolution from the single-celled protozoans or, like some
other worms, a degenerate form of many-celled animals. It might be
maintained that they represent a distinct branch of the animal kingdom.
The body of a dicyemid consists of a single cell, almost half an inch
long, in the form of a hollow tube, surrounded by a layer of small
cells. The immediate offspring are formed and, in some cases, live
their entire lives and reproduce in turn, inside one of these “skin”
cells. The grandchildren break through the body of the grandparent at
any place they choose, apparently without causing any wound, and live
for a short time as free-swimming animals until they find an octopus
whose kidneys they can enter. Then the whole life cycle starts over
again.
Apparently the infestation in no way injures the octopus and the worms
are of no practical importance in the world. Each kind of octopus
or squid in coastal areas has its own particular species of these
parasites of which about 35 kinds are known.
The worm’s body contains no organs, tissues or glands in the usual
sense of the word.
Before being born the larvae attain their full complement of body
cells, are able to swim about, and have within them the germ cells that
will give rise to the next generation. Birth is very simple. The larvae
just push out, or are squeezed out, through the sides or ends of their
parent at almost any point. The parent continues to develop and bear
more larvae in the same manner. The number developing at any one time
in the cell may range from one or two to 100 or more.
These larvae remain in the octopus as fully developed worms. But at
certain times the germ cells develop into much smaller individuals,
called infusorigens, hard to distinguish from large protozoa. These
never leave the birth cell inside the parent, but produce germ cells
of their own which develop into free-swimming creatures known as
infusoriforms. These break away from the grandparent worm and from the
octopus and become free-swimming animals. They are microscopic, less
than a 300th of an inch long. They live from three days to a week. Here
may be the borderline between single-celled and multi-celled animals—or
perhaps the greatest degeneration in animal life.
_The Monster Bear of Kamchatka_
A gigantic black bear, probably the largest of flesh-eating animals,
lives in the dense, hardly explored pine forests of southern Kamchatka.
This creature still is unknown to science. So far as known it never has
been seen by a white man. There is, however, considerable evidence for
its existence presented in a report made several years ago by Dr. Sten
Bergman of the State Museum of Natural History at Stockholm, who spent
two years on the Kamchatka peninsula.
Photographs have been taken of this animal’s footprints in the snow.
It leaves a track 15 inches long and ten inches wide. Dr. Bergman was
shown a pelt of the giant bear. It was the largest bearskin he ever
had seen, deep black in color, and covered with short hair in striking
contrast to the long hair of other Kamchatkan bears. He also saw a
gigantic bear skull, the teeth of which indicate that it belonged to a
young individual.
Apparently this Kamchatkan black bear exceeds in size the Kodiak
Island bear, which lives across Bering Strait and is the largest
known flesh-eating mammal. The wildness of the country and its dense
vegetation have protected the giant bear from naturalists and hunters.
The whole land is a veritable paradise for bears who hide away in the
dense thickets along the Kamchatkan rivers and subsist on the abundant
salmon. They are so numerous that a native does not dare venture into
the bush in summer without first shouting to let the bears know he is
coming. They will keep out of a man’s way if they are warned, but are
likely to attack him if surprised.
The great majority of the Kamchatkan bears are relatively small
animals, comparable to those of northern Europe. Some are black, but
the majority are yellowish-white or light brown. The giant animal may
be an extreme variation of this race, or may represent an entirely
different species. He naturally is the subject of much native
legendary. Some stories have been interpreted as indicating that
mammoths existed within the time of man in the northern wildernesses of
both hemispheres, but such a giant bear would fit the descriptions as
well as would a small elephant-like creature.
If it were not for the great numbers of smaller bears, man scarcely
could subsist in this country. There are, for example, no roads through
the desolate land between the villages. But all along the rivers and
through the forests are well-marked paths made by the bears who seem to
have an engineering instinct in choosing the most logical places for
crossing morasses and mountains. These paths are about the only means
of human communication and eventually, if the land ever is settled,
will become the roads. In the same way elephant trails in Africa and
India and bison trails in the United States became the hard-surfaced
highways of today. Engineers hardly can improve on the instinct of the
animals.
The small bears also play an important part in the domestic economy
of the few inhabitants. The thick, warm pelt is used as a bed. Out of
the skin the natives make reins, snowshoes and dog traces. The meat is
much appreciated. In remoter parts of the country the linings of the
intestines are used for windows instead of glass. Many of the native
medicines are derived from the bear.
Both among the Kamchatka natives and the Ainu of northern Japan the
animal is revered as a god—the concept being that the great celestial
bear out of his benevolence to men provides creatures in his own form
to furnish them food and clothing.
_Strange Denizens of the Deep_
Most fearsome of all sharks in appearance is Isistius braziliensis,
found in the tropical Atlantic, Indian and Pacific oceans. It is a
wine-brown colored creature with sharp teeth set in 20 rows which glow
at night with an unearthly light.
“When the specimen, taken at night, was removed into a dark apartment
it afforded a very extraordinary spectacle,” relates naturalist F. D.
Bennett. “The entire inferior surface of the body and head emitted a
vivid, greenish phosphorescent gleam, imparting to the creature, by its
own light, a truly ghastly and terrible appearance. The luminous effect
was constant and not perceptibly increased by agitation or friction.
“When the shark expired, which was not until it had been out of the
water more than three hours, the luminous appearance faded entirely
from the abdomen and more gradually from other parts, lingering longest
around the jaws and on the fins. The only part of the under surface
of the animal which was free from the luminosity was the black collar
around the throat.”