8: Chapter VIII
<< 7: Chapter VII || 9: Chapter IX >>
How little can the inhabitant of a cold or temperate climate
appreciate the vast amount of "life" in a tropical country. The
combined action of light, heat and moisture calls into existence
myriads of creeping things, the offspring of the decay of
vegetation. "Life" appears to emanate from "death" - the
destruction of one material seems to multify the existence of
another - the whole surface of the earth seems busied in one vast
system of giving birth.
An animal dies - a solitary beast - and before his unit life has
vanished for one week, bow many millions of living creatures owe
their birth to his death? What countless swarms of insects have
risen from that one carcase! - creatures which never could have
been brought into existence were it not for the presence of one
dead body which has received and hatched the deposited eggs of
millions that otherwise would have remained unvivified.
Not a tree falls, not a withered flower droops to the ground, not
a fruit drops from the exhausted bough, but it is instantly
attacked by the class of insect prepared by Nature for its
destruction. The white ant scans a lofty tree whose iron-like
timber and giant stem would seem to mock at his puny efforts; but
it is rotten at the core and not a leaf adorns its branches, and
in less than a year it will have fallen to the earth a mere
shell; the whole of the wood will have been devoured.
Rottenness of all kinds is soon carried from the face of the land
by the wise arrangements of Nature for preserving the world from
plagues and diseases, which the decaying and unconsumed bodies of
animals and vegetables would otherwise engender.
How beautiful are all the laws of Nature! how perfect in their
details! Allow that the great duty of the insect tribe is to
cleanse the earth and atmosphere from countless impurities
noxious to the human race, how great a plague would our
benefactors themselves become were it not for the various classes
of carnivorous insects who prey upon them, and are in their turn
the prey of others! It is a grand principle of continual strife,
which keeps all and each down to their required level.
What a feast for an observant mind is thus afforded in a tropical
country! The variety and the multitude of living things are so
great that a person of only ordinary observation cannot help
acquiring a tolerable knowledge of the habits of some of the most
interesting classes. In the common routine of daily life they
are continually in his view, and even should he have no taste for
the study of Nature and her productions, still one prevailing
characteristic of the insect tribe must impress itself upon his
mind. It is the natural instinct not simply of procreating their
species, but of laying by a provision for their expected
offspring. What a lesson to mankind! what an example to the
nurtured mind of mail from one of the lowest classes of living
things!
Here we see no rash matrimonial engagements; no penniless lovers
selfishly and indissolubly linked together to propagate large
families Of starving children. Ail the arrangements of the
insect tribe, though prompted by sheer instinct are conducted
with a degree of rationality that in some cases raises the mere
instinct of the creeping thing above the assumed "reason" of man.
The bird builds her nest and carefully provides for the comfort
of her young long ere she lays her fragile egg. Even look at
that vulgar-looking beetle, whose coarse form would banish the
idea of any rational feeling existing in its brain - the
Billingsgate fish-woman of its tribe in coarseness and rudeness
of exterior (Scarabaeus carnifex) - see with what quickness she
is running backward, raised almost upon her head, while with her
bind legs she trundles a large ball; herself no bigger than a
nutmeg, the ball is four times the size. There she goes along the
smooth road. The ball she has just manufactured from some
fresh-dropped horse-dung; it is as round as though turned by a
lathe, and, although the dung has not lain an hour upon the
ground, she and her confederates have portioned out the spoil,
and each has started off with her separate ball. Not a particle
of horsedung remains upon the road. Now she has rolled the ball
away from the hard road, and upon the soft, sandy border she has
stopped to rest. No great amount of rest; she plunges her head
into the ground, and with that shovel-like projection of stout
horn she mines her way below: she has disappeared even in these
few seconds.
Presently the apparently deserted ball begins to move, as though
acted on by some subterranean force; gradually it sinks to the
earth, and it vanishes altogether.
Some persons might imagine that she feeds upon the ordure, and
that she has buried her store as a dog hides a bone; but this is
not the case; she has formed a receptacle for her eggs, which she
deposits in the ball of dung, the warmth of which assists in
bringing the larvae into life, which then feed upon the manure.
It is wonderful to observe with what rapidity all kinds of dung
are removed by these beetles. This is effected by the active
process of rolling the loads instead of carrying, by which method
a large mass is transported at once.
The mason-fly is also a ball-maker, but she carries her load and
builds an elaborate nest. This insect belongs to the order
"Hymenoptera," and is of the Ichneumon tribe, being a variety of
upward of four hundred species of that interesting fly.
The whole tribe of Ichneumon are celebrated for their courage; a
small fly will not hesitate to attack the largest cockroach, who
evinces the greatest terror at sight of his well-known enemy; but
the greatest proof of valor in a fly is displayed in the war of
the ichneumon against the spider.
There is a great variety of this insect in Ceylon, from the large
black species, the size of the hornet down to the minute
tinsel-green fly, no bigger than a gnat; but every one of these
different species wages perpetual war against the arch enemy of
flies.
In very dry weather in some districts, when most pools and
water-holes are dried up, a pail of water thrown upon the ground
will as assuredly attract a host of mason-flies as carrion will
bring together "blow-flies." They will be then seen in excessive
activity upon the wet earth, forming balls of mud, by rolling the
earth between their fore feet until they have manufactured each a
pill. With this they fly away to build their nest, and
immediately return for a further supply.
The arrangement of the nest is a matter of much consideration, as
the shape depends entirely upon the locality in which it is
built: it may be in the corner of a room, or in a hole in a wall,
or in the hollow of a bamboo; but wherever it is, the principle
is the same, although the shape of the nest may vary. Everything
is to be hermetically sealed.
The mason-fly commences by flattening the first pill of clay upon
the intended site (say the corner of a room); she then spreads it
in a thin layer over a surface of about two inches, and retires
for another ball of clay. This she dabs upon the plastic
foundation, and continues the apparently rude operation until
some twenty or thirty pills of clay are adhering at equal
distances. She then forms these into a number of neat
oval-shaped cells, about the size of a wren's egg, and in each
cell she deposits one egg. She then flies off in search of
spiders, which are to be laid tip in stores within the cells as
food for the young larvae, when hatched.
Now the transition from the larva to the fly takes place in the
cell, and occupies about six weeks from the time the egg is first
laid; thus, as the egg itself is not vivified for some weeks
after it is deposited, the spiders have to be preserved in a
sound and fresh state during that interval until the larva is in
such an advanced stage as to require food.
In a tropical country every one knows that a very few hours
occasion the putrefaction of all dead animal substances;
nevertheless these spiders are to be kept fresh and good, like
our tins of preserved meats, to be eaten when required.
One, two, or even three spiders, according to their size, the
mason-fly deposits in each cell, and then closes it hermetically
with clay. The spiders she has pounced upon while sunning
themselves in the centre of their delicate nets, and they are
hurried off in a panic to be converted into preserved provisions.
Each cell being closed, the whole nest is cemented over with a
thick covering of clay. In due time the young family hatch, eat
their allowance of spiders, undergo their torpid change, and
emerge from their clay mansion complete mason-flies.
Every variety of Ichneumon, however (in Ceylon), chooses the
spider as the food for its young. It is not at all uncommon to
find a gun well loaded with spiders, clay and grubs, some
mason-fly having chosen the barrel for his location. A bunch of
keys will invite a settlement of one of the smaller species, who
make its nest in the tube of a key, which it also fills with
minute spiders.
In attacking the spider, the mason-fly his a choice of his
antagonist, and he takes good care to have a preponderance of
weight on his own side. His reason for choosing this in
preference to other insects for a preserved store may be that the
spider is naturally juicy, plump and compact, combining
advantages both for keeping and packing closely.
There are great varieties of spiders in Ceylon, one of which is
of such enormous size as to resemble the Aranea avicularia of
America. This species stands on an area of about three inches,
and never spins a web, but wanders about and lives in holes; his
length of limb, breadth of thorax and powerful jaws give him a
most formidable appearance. There is another species of a
large-sized spider who spins a web of about two and a half feet
in diameter. This is composed of a strong, yellow, silky fibre,
and so powerful is the texture that a moderate-sized walking-cane
thrown into the web will be retained by it. This spider is about
two inches long, the color black, with a large yellow spot upon
the back, and the body nearly free from hair.
Some years ago an experiment was made in France of substituting
the thread of the spider for the silk of the silkworm: several
pairs of stockings and various articles were manufactured with
tolerable success in this new material, but the fibre was
generally considered as too fragile.
A sample of such thread as is spun by the spider described could
not have failed to produce the desired result, as its strength is
so great that it can be wound upon a card without the slightest
care required in the operation. The texture is far more silky
than the fibre commonly produced by spiders, which has more
generally the character of cotton than of silk.
Should this ever be experimented on, a question might arise of
much interest to entomologists, whether a difference in the food
of the spider would affect the quality of the thread, as is well
known to be the case with the common silkworm.
A Ceylon night after a heavy shower of rain is a brilliant sight,
when the whole atmosphere is teeming with moving lights bright as
the stars themselves, waving around the tree-tops in fiery
circles, now threading like distant lamps through the intricate
branches and lighting up the dark recesses of the foliage, then
rushing like a shower of sparks around the glittering boughs.
Myriads of bright fire-flies in these wild dances meet their
destiny, being entangled in opposing spiders' webs, where they
hang like fairy lamps, their own light directing the path of the
destroyer and assisting in their destruction.
There are many varieties of luminous insects in Ceylon. That
which affords the greatest volume of light is a large white grub
about two inches in length, This is a fat, sluggish animal, whose
light is far more brilliant than could be supposed to emanate
from such a form.
The light of a common fire-fly will enable a person to
distinguish the hour on a dial in a dark night, but the glow from
the grub described will render the smallest print so legible that
a page may be read with case. I once tried the experiment of
killing the grub, but the light was not extinguished with life,
and by opening the tail, I squeezed out a quantity of glutinous
fluid, which was so highly phosphorescent that it brilliantly
illumined the page of a book which I had been reading by its
light for a trial.
All phosphorescent substances require friction to produce their
full volume of light; this is exemplified at sea during a calm
tropical night, when the ocean sleeps in utter darkness and
quietude and not a ripple disturbs the broad surface of the
water. Then the prow of the advancing steamer cuts through the
dreary waste of darkness and awakens into fiery life the spray
which dashes from her sides. A broad stream of light illumines
the sea in her wake, and she appears to plough up fire in her
rush through the darkened water.
The simple friction of the moving mass agitates the millions of
luminous animalcules contained in the water; in the same manner a
fish darting through the sea is distinctly seen by the fiery
course which is created by his own velocity.
All luminous insects are provided with a certain amount of
phosphorescent fluid, which can be set in action at pleasure by
the agitation of a number of nerves and muscles situated in the
region of the fluid and especially adapted to that purpose. It
is a common belief that the light of the glow-worm is used as a
lamp of love to assist in nocturnal meetings, but there can be
little doubt that the insect makes use of its natural brilliancy
without any specific intention. It is as natural for the
fire-fly to glitter by night as for the colored butterfly to be
gaudy by day.
The variety of beautiful and interesting insects is so great in
Ceylon that an entomologist would consider it a temporary
elysium; neither would he have much trouble in collecting a host
of different species who will exhibit themselves without the
necessity of a laborious search. Thus, while he may be engaged
in pinning out some rare specimen, a thousand minute eye-flies
will be dancing so close to his eyeballs that seeing is out of
the question. These little creatures, which are no larger than
pin's heads, are among the greatest plagues in some parts of the
jungle; and what increases the annoyance is the knowledge of the
fact that they dance almost into your eyes out of sheer vanity.
They are simply admiring their own reflection in the mirror of
the eye; or, may be, some mistake their own reflected forms for
other flies performing the part of a "vis-à-vis" in their
unwearying quadrille.
A cigar is a specific against these small plagues, and we will
allow that the patient entomologist has just succeeded in putting
them to flight and has resumed the occupation of setting out his
specimen. Ha! see him spring out of his chair as though
electrified. Watch how, regardless of the laws of buttons, he
frantically tears his trowsers from his limbs; he has him! no he
hasn't! - yes he has! - no - no, positively he cannot get him
off. It is a tick no bigger than a grain of sand, but his bite
is like a red-hot needle boring into the skin. If all the royal
family had been present, he could not have refrained from tearing
off his trowsers.
The naturalist has been out the whole morning collecting, and a
pretty collection he has got - a perfect fortune upon his legs
alone. There are about a hundred ticks who have not yet
commenced to feed upon him; there are also several fine specimens
of the large flat buffalo tick; three or four leeches are
enjoying themselves on the juices of the naturalist; these he had
not felt, although they had bitten him half an hour before; a
fine black ant has also escaped during the recent confusion,
fortunately without using his sting.
Oil is the only means of loosening the hold of a tick; this
suffocates him and he dies; but he leaves an amount of
inflammation in the wound which is perfectly surprising in so
minute an insect. The bite of the smallest species is far more
severe than that of the large buffalo or the deer tick, both of
which are varieties.
Although the leeches in Ceylon are excessively annoying, and
numerous among the dead leaves of the jungle and the high grass,
they are easily guarded against by means of leech-gaiters: these
are wide stockings, made of drill or some other light and close
material, which are drawn over the foot and trowsers up to the
knee, under which they are securely tied. There are three
varieties of the leech : the small jungle leech, the common leech
and the stone leech. The latter will frequently creep up the
nostrils of a dog while he is drinking in a stream, and, unlike
the other species, it does not drop off when satiated, but
continues to live in the dog's nostril. I have known a leech of
this kind to have lived more than two months in the nose of one
of my hounds; he was so high up that I could only see his tail
occasionally when lie relaxed to his full length, and injections
of salt and water had no effect on him. Thus I could not relieve
the dog till one day when the leech descended, and I observed the
tail working in and out of the nostril; I then extracted him in
the usual way with the finger and thumb and the tail of the coat.
I should be trespassing too much upon the province of the
naturalist, and attempting more than I could accomplish, were I
to enter into the details of the entomology of Ceylon; I have
simply mentioned a few of those insects most common to the
every-day observer, and I leave the description of the endless
varieties of classes to those who make entomology a study.
It may no doubt appear very enticing to the lovers of such
things, to hear of the gorgeous colors and prodigious size of
butterflies, moths and beetles; the varieties of reptiles, the
flying foxes, the gigantic crocodiles; the countless species of
waterfowl, et hoc genus omne; but one very serious fact is apt to
escape the observation of the general reader, that wherever
insect and reptile life is most abundant, so sure is that
locality full of malaria and disease.
Ceylon does not descend to second-class diseases: there is no
such thing as influenza; whooping-cough, measles, scarlatina,
etc., are rarely, if ever, heard of; we ring the changes upon
four first-class ailments - four scourges, which alternately
ascend to the throne of pestilence and annually reduce the circle
of our friends - cholera, dysentery, small-pox and fever. This
year (1854) there has been some dispute as to the routine of
succession; they have accordingly all raged at one time.
The cause of infection in disease has long been a subject of
controversy among medical men, but there can be little doubt
that, whatever is the origin of the disease, the same is the
element of infection. The question is, therefore, reduced to the
prime cause of the disease itself.
A theory that animalcules are the cause of the various contagious
and infectious disorders has created much discussion; and
although this opinion is not generally entertained by the
faculty, the idea is so feasible, and so many rational arguments
can be brought forward in its support, that I cannot help
touching upon a topic so generally interesting.
In the first place, nearly all infectious diseases predominate in
localities which are hot, damp, swampy, abounding in stagnant
pools and excluded from a free circulation of air. In a tropical
country, a residence in such a situation would be certain death
to a human being, but the same locality will be found to swarm
with insects and reptiles of all classes.
Thus, what is inimical to human life is propitious to the insect
tribe. This is the first step in favor of the argument.
Therefore, whatever shall tend to increase the insect life must
in an inverse ratio war with human existence.
When we examine a drop of impure water, and discover by the
microscope the thousands of living beings which not only are
invisible to the naked eye, but some of whom are barely
discoverable even by the strongest magnifying power, it certainly
leads to the inference, that if one drop of impure fluid contains
countless atoms endowed with vitality, the same amount of impure
air may be equally tenanted with its myriads of invisible
inhabitants.
It is well known that different mixtures, which are at first pure
and apparently free from all insect life, will, in the course of
their fermentation and subsequent impurity, generate peculiar
species of animalcules. Thus all water and vegetable or animal
matter, in a state of stagnation and decay, gives birth to insect
life; likewise all substances of every denomination which are
subjected to putrid fermentation. Unclean sewers, filthy hovels,
unswept streets, unwashed clothes, are therefore breeders of
animalcules, many of which are perfectly visible without
microscopic aid.
Now, if some are discernible by the naked eye, and others are
detected in such varying sizes that some can only just be
distinguished by the most powerful lens, is it not rational to
conclude that the smallest discernible to human intelligence is
but the medium of a countless race? that millions of others still
exist, which are too minute for any observation?
Observe the particular quarters of a city which suffers most
severely during the prevalence of an epidemic, In all dirty,
narrow streets, where the inhabitants are naturally of a low and
uncleanly class, the cases will be tenfold. Thus, filth is
admitted to have at least the power of attracting disease, and we
know that it not only attracts, but generates animalcules;
therefore filth, insects and disease are ever to he seen closely
linked together.
Now, the common preventives against infection are such as are
peculiarly inimical to every kind of insect; camphor, chloride of
lime, tobacco-smoke, and powerful scents and smokes of any kind.
The first impulse on the appearance of an infectious disease is
to purify everything as much as possible, and by extra
cleanliness and fumigations to endeavor to arrest its progress.
The great purifier of Nature is a violent wind, which usually
terminates an epidemic immediately; this would naturally carry
before it all insect life with which the atmosphere might be
impregnated, and the disease disappears at the same moment. It
will he well remembered that the plague of locusts inflicted upon
Pharaoh was relieved in the same manner: "And the Lord turned a
mighty strong west wind, which took away the locusts and cast
them into the Red Sea; there remained not one locust in all the
coasts of Egypt."
Every person is aware that unwholesome air is quite poisonous to
the human system as impure water; and seeing that the noxious
qualities of the latter are caused by animalcules, and that the
method used for purifying infected air are those most generally
destructive to insect life, it is not irrational to conclude that
the poisonous qualities of bad water and bad air arise from the
same cause.
Man is being constantly preyed upon by insects; and were it not
for ordinary cleanliness, he would become a mass of vermin; even
this does not protect him from the rapacity of ticks, mosquitoes,
fleas and many others. Intestinal worms feed on him within, and,
unseen, use their slow efforts for his destruction.
The knowledge of so many classes which actually prey upon the
human system naturally leads to the belief that many others
endowed with the same propensities exist, of which we have at
present no conception. Thus, different infectious disorders
might proceed from peculiar species of animalcules, which, at
given periods, are wafted into certain countries, carrying
pestilence and death in their invisible course.
A curious phenomenon has recently occurred at Mauritus, where
that terrible scourge, the cholera, has been raging with
desolating effect.
There is a bird in that island called the "martin," but it is
more property the "mina." This bird is about the size of the
starling, whose habits its possesses in a great degree. It
exists in immense numbers, and is a grand destroyer of all
insects. On this account it is seldom or never shot at,
especially as it is a great comforter to all cattle, whose hides
it entirely cleans from ticks and other vermin, remaining for
many hours perched upon the back of one animal, while its bill is
actively employed in searching out and destroying every insect.
During the prevalence of the cholera at Mauritius these birds
disappeared. Such a circumstance had never before occurred, and
the real cause of their departure is still a mystery.
May it not have been, that some species of insect upon which they
fed had likewise migrated, and that certain noxious animalcules,
which had been kept down by this class, had thus multiplied
within the atmosphere until their numbers caused disease? All
suppositions on such a subject must, however, remain in
obscurity, as no proof can be adduced of their correctness. The
time may arrive when science may successfully grapple with all
human ailments, but hitherto that king of pestilence, the
"cholera," has reduced the highest medical skill to miserable
uncertainty.
Upon reconsidering the dangers of fevers, dysentery, etc., in the
swampy and confined districts described, the naturalist may
become somewhat less ardent in following his favorite pursuit.
Of one fact I can assure him that no matter how great the natural
strength of his constitution, the repeated exposure to the
intense heat of the sun, the unhealthy districts that he will
visit, the nights redolent of malaria, and the horrible water
that he must occasionally drink, will gradually undermine the
power of the strongest man. Both sportsman and naturalist in
this must share alike.
No one who has not actually suffered from the effect can
appreciate the misery of bad water in a tropical country, or the
blessings of a cool, pure draught. I have been in districts of
Ceylon where for sixteen or twenty miles not a drop of water is
to be obtained fit for an animal to drink; not a tree to throw a
few yards of shade upon the parching ground; nothing but stunted,
thorny jungles and sandy, barren plains as far as the eye can
reach; the yellow leaves crisp upon the withered branches, the
wild fruits hardened for want of sap, all moisture robbed from
vegetation by the pitiless drought of several months.
A day's work in such a country is hard indeed carrying a heavy
rifle for some five-and-twenty miles, sometimes in deep sand,
sometimes on good ground, but always exposed to the intensity of
that blaze, added to the reflection from the sandy soil, and the
total want of fresh air and water. All Nature seems stagnated; a
distant pool is seen, and a general rush takes place toward the
cheering sight. The water is thicker than pea soup, a green scum
floats through the thickened mass, and the temperature is upward
of 130 Fahrenheit. All kinds of insects are swarming in the
putrid fluid, and a saltish bitter adds to its nauseating flavor.
I have seen the exhausted coolies spread their dirty cloths on
the surface, and form them into filters by sucking the water
through them. Oh for a glass of Newera Ellia water, the purest
and best that ever flows, as it sparkles out of the rocks on the
mountain-tops! what pleasure so perfect as a long, deep and
undisturbed draught of such cold, clear nectar when the throat is
parched with unquenchable thirst!
In some parts of Ceylon, especially in the neighborhood of the
coast, where the land is flat and sandy, the water is always
brackish, even during the rainy season, and in the dry months it
is undrinkable.
The natives then make use of a berry for cleansing it and
precipitating the impurities. II know the shrub and the berry
well, but it has no English denomination. The berries are about
the size of a very large pea, and grow in clusters of from ten to
fifteen together, and one berry is said to be sufficient to
cleanse a gallon of water. The method of using them is curious,
although simple. The vessel which is intended to contain the
water, which is generally an earthen chatty, is well rubbed in
the inside with a berry until the latter, which is of a horny
consistency, like vegetable ivory, is completely worn away. The
chatty is then filled with the muddy water, and allowed to stand
for about an hour or more, until all the impurities have
precipitated to the bottom and the water remains clear.
I have constantly used this berry, but I certainly cannot say
that the water has ever been rendered perfectly clear; it has
been vastly improved, and what was totally undrinkable before has
been rendered fit for use; but it has at the best been only
comparatively good; and although the berry has produced a decided
effect, the native accounts of its properties are greatly
exaggerated.
During the prolonged droughts, many rivers of considerable
magnitude are completely exhausted, and nothing remains but a dry
bed of said between lofty banks. At these seasons the elephants,
being hard pressed for water, make use of their wonderful
instinct by digging holes in the dry sand of the river's bed;
this they perform with the horny toes of their fore feet, and
frequently work to a depth of three feet before they discover the
liquid treasure beneath. This process of well-digging almost
oversteps the boundaries of instinct and strongly, savors of
reason, the two powers being so nearly connected that it is
difficult in some cases to define the distinction. There are so
many interesting cases of the wonderful display of both these
attributes in animals, that I shall notice some features of this
subject in a separate chapter.
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