interesting process. The spider hangs herself by a thread from the
spinnerets to the centre of the web. In a short time the skin cracks
around the thorax, just over the first joints of the legs, and the
top part falls forward, being held only at the front edge. The skin
of the abdomen now breaks irregularly along the sides and back, and
shrinks together in a bunch, leaving the spider suspended only by a
short thread from the spinnerets, her legs still being trammelled by
the old skin. Fifteen minutes of violent exertion releases her from the
encumbrance, when she drops down, hanging by her spinnerets like a wet
rag. She can do nothing in this condition, not even draw her legs away
from an approaching hand. In ten or twelve minutes the legs show signs
of strengthening, and she is able to draw them gradually towards her. A
few up-and-down movements, and she manages to get into the web again.
That which, more than anything else, discriminates spiders from other
animals is their habit of spinning webs. Some of the mites spin
irregular threads upon plants, or cocoons for their eggs, and many
insects cocoons in which to undergo their changes from larva to imago,
but in the spiders the spinning-organs are much more complicated, and
used for a greater variety of purposes, for making egg-cocoons, silk
linings to their nests, and nets for catching insects. The spider’s
thread differs from that of insects, in being constituted of a great
number of finer threads laid together, while soft enough to coalesce
into one. Each spinneret is provided with a number of little tubes,
which convey the viscid liquid that forms the thread from glands in the
spider’s body. In Agalena the two hinder spinnerets are long, and have
spinning-tubes along the under side of the last joint.
When about to produce a thread the spider presses the spinnerets
against some object and forces out from each tube enough of the
secretion to adhere to it, when the spinnerets are moved away, drawing
the viscid liquid out, which hardens at once into threads for each
tube. A band of threads is formed when the spinnerets are kept apart,
but when closed together the fine threads unite into one or more large
ones. Commonly the spinning is aided by the hinder feet, which guide
the thread, keeping it clear of surrounding objects, and even pulling
it from the spinnerets.
Spiders are best known and hated as animals that bite. Their
biting-apparatus, the mandibles, are located in front of the head.
Partly in the basal joints of these organs and partly in the head, the
poison-glands are seated, from which is discharged through a tube the
venom, which makes spiders so much to be feared. This tube opens at the
point of the claw of the mandible. When the apparatus is not in use
the claws are closed up against the parts between the rows of teeth;
but when the jaws are opened to bite the claws are turned outward, so
that their points can be made to penetrate anything that comes between
the jaws. The ordinary function of the mandibles is the killing and
crushing of insects, so that the soft parts can be eaten by the spider,
and in this preparation they are substantially aided by the maxillæ.
Spiders will sometimes chew an insect for hours, until it becomes a
mere ball of skin, only swallowing such bits as may happen to be sucked
in with the blood. Let alone and unmolested, they bite nothing except
insects that are useful for food. But when attacked and cornered,
all species open their jaws and bite if they can, their ability to
do so depending upon their size and the strength of their jaws.
Notwithstanding the large number of pimples and stings ascribed to
spiders, undoubted cases of their biting the human skin are exceedingly
rare, and the stories of death, insanity and lameness from spider-bites
are probably all untrue. Many experiments have been made to test the
effect of the bites of spiders on animals. Insects succumb most readily
to their bites, some sooner than others, but birds, except when bitten
by the larger Mygale, recover after the lapse of a few hours. The
effect upon man, even when the bite is deep enough to draw blood, is
like the pricks of a needle, attended by little or no inflammation or
pain. Even in cases where death among insects and birds ensues it is
claimed by the authorities, men as eminent as Blackwall, Moggridge and
Dufour, that the secretion from spiders’ jaws is not poisonous, but
that the animals die, when bitten, from loss of blood and mechanical
injury.
Such is the prejudice against the spider, that its presence, no matter
where found, whether in the open field or in a corner of the house,
is an inducement for its inveterate enemy, man, to sweep it to the
ground or floor and crush its frail life out with one blow of the foot.
Few know, or care to know, it would seem, the good it does for man.
He owes to it, in a large measure, the protection of his crops, and
no little of the comfort he enjoys in life. Spiders are carnivorous
creatures, and destroy vast number of insects, many of which are man’s
worst enemies. They merit, and deservingly, too, his kindness and
protection for the benefits they confer.
Tarantulas have been supposed to produce epilepsy by their bites,
which could only be relieved by music of certain kinds. Such stories,
and they have been widely circulated and believed, are the veriest
nonsense, for tarantula-bites produce no such effects nowadays. These
spiders, which live in holes in sand, out of which they reach after
passing insects, are no more savage in their habits than other spiders,
for Dufour, a celebrated French naturalist, once kept one that soon
learned to take flies from his fingers without manifesting the least
disposition to bite. Different species quickly learn, when treated
with kindness, to regard man as their friend. I have seen Agalena take
food from the hand out of a pair of forceps, or water from a brush,
and even to reach on tiptoe after it from the mouth of a bottle placed
for her accommodation. Though naturally timid and shy, and prone
to flee to her funnel on man’s approach, yet she has been known to
permit the most unexpected familiarities without fear or resentment.
Many a female has taken from my hand the proffered fly, and submitted
to the gentle caresses of my finger down the back and abdomen with
the most pleasurable satisfaction. They have come at the sound of my
voice, dancing upon their sheeted web like one gone mad, so perfectly
carried away with delight. An interesting experience of last summer
during a brief stay in the country seems apropos at this time. While
sauntering carelessly along a forest-road I came unexpectedly upon a
rustic bridge, with a railing on one side, which overspanned a small
water-course. Leaning for rest and support against the railing, soon
my attention was arrested by a huge female spider, which I recognized
as _Epeira domiciliorum_. She was evidently in quest of something,
as I was led to suspect from her seemingly thoughtful and deliberate
movements. I watched her closely and criticisingly for a long while,
and in one of her contemplative moods, when she stood perfectly
motionless and fixed as it were to the railing, I reached out my
finger rather impulsively and began stroking her along the abdomen,
a familiarity which she did not resent, and which seemed to give her
the most intense delight. When the caressing had ceased, she would
turn round and confront her newly-made acquaintance, but the lifting
of the finger was always the signal for her to assume an attitude of
the most perfect quiescence. That she enjoyed these little attentions
there cannot be a shadow of doubt, or actions are no use in the
interpretation of feeling. Had they been painful, she would have sought
relief in flight, or in the manifestation of an untoward disposition
towards her unintentional persecutor.
BOOK-LOVERS.
Living in chinks and crannies of ranges in our homes, and occasionally
in bookcases and closets where glutinous and sugary matters abound,
but which has probably not been met with elsewhere, is a strange but
beautiful little creature which, as far as can be determined, goes
through the brief round of its existence without a name to distinguish
it from its fellows.
Few entomologists have given any special attention to its family
relationships. The possession of certain bristle-like appendages which
terminate the abdomen, and which are no doubt comparable with the
abdominal legs of the Myriopods, or Thousand Legs, classes it with the
Bristle-tails, or Lepismas. In general form, a likeness to the larva
of Perla, a net-veined neuropterous insect, is manifest, or to the
narrow-bodied species of Blattariæ, or Cockroaches, when divested of
wings.
_Lepisma saccharina_, of Europe, which is indistinguishable from our
ordinary American form, is far from uncommon in old, damp houses. Its
structure is less complicated than the heat-loving species to which I
have alluded, and there are likewise differences of habits which show
themselves to the close investigator of natural phenomena.
Not unlike the cockroaches, which our little denizen of the hearth
somewhat vaguely resembles in form, it affects hot, dry localities, and
is always astir at nights in quest of its fare, for it disdains the
light of the day and the consequent publicity of its deeds of shame and
plunder.
Many a housewife in the discharge of duty has unearthed, so to speak,
the miscreant from its hidden retreat, and sought by foot or hand to
crush the life that dares obtrude its uncleanly presence in her larder,
but the cunning, swift-footed Lepisma darts off, like a streak of
light, to some near-by crack or breach, where it manages to hide from
threatening danger. The bodies of these nimble, silent-moving creatures
being coated in a suit of shining mail, which the arrangement of the
scales so very much resembles, they have a weird and ghostly look.
This appearance, and the swiftness of their movement, which the eye
can hardly trace, have led the vivid mind of man, in country town and
village, to dub them “silver witches.”
So fleet of foot are they, and so like a wave of blurred light they
cross the vision, that it is vain to try to figure what they are in
shape and look. In death they yield their all of earth to prying
science. Their body’s form is narrow, flattened; their legs in pairs of
threes, each of six joints consisting, the basal joints broad, flat,
triangular, the tarsal large, in number two, and armed at end with pair
of claws incurved. The three thoracic segments are very like in size,
and eight abdominals, of similar length and width. So weak it seems
the rather long abdomen is, that two pairs or six of bristles, simple,
unjointed, and freely movable, serve as support, and also, as in other
groups of insects, as organs locomotive.
The mode of antenna-insertion--and the same prevails in the entire
family--is much like that of the Myriopods, the front of the head
being flattened and concealing, as in the Centipedes, the base of the
antennæ. Indeed, the head of any of the Bristle-tails, as seen from
above, bears a general resemblance in some of its features to that of
the Centipede and its allies, and so, in a less degree, does the head
of the larvæ of certain beetles and neuropters. The eyes are compound,
the individual facets constituting a sort of heap. The mouth-parts are
readily compared with those of the larva of Perla, the rather large,
stout mandibles being hid at their tips by the upper lip, which moves
freely up and down when the creature opens its mouth. In length the
mandible is three times its breadth, and furnished with three sharp
teeth on the outer edge, and with a broad cutting margin within,
and still further inwards with a number of straggling small spines.
The lower lip is broad and stout, with a distinct medium suture,
which indicates a former separation in embryonic life into a pair of
appendages. Its palpi are three-jointed, the joints being broad, and
directed backwards in life, and not forwards, as in the higher insecta.
[Illustration: LEPISMAS AT WORK.
How Books are Destroyed.]
Perhaps not more than a half-dozen species of Lepisma are known to
exist in this country. Our commonest form is very abundant in the
Middle States under stones and leaves in forests, and northward in
damp houses, where it has much of the habits of the cockroach, eating
clothes, tapestry, silken trimmings of furniture, and doing great
mischief to libraries by devouring the paste and mutilating the leaves
and covers of books. Our heat-loving form, which is apparently allied
to the _Lepisma thermophila_ of Europe, and which may be an imported
species, is quite as destructive as its nearest of kin _Lepisma
saccharina_. It does not confine its ravages to closets and pantries,
and feed upon sugar and cake and pastry, but has latterly taken to
bookcases, where it leads an easy, comfortable life, without fear of
molestation.
So delicately constructed are the Lepismas, and so seemingly feeble
the breath of life which animates their frail houses of clay, that
nature has endowed them with qualities of mind and body which eminently
fit them for the part they have to play in the world. She has made
them lovers of darkness rather than light, endowed them with keenness
of vision and hearing truly wonderful, and given them a celerity of
movement which enables them to outstrip in speed the fleetest of their
insect-enemies, and even to baffle the well-directed efforts of man
for their destruction. The silver-coated armor with which they are
invested is so glossy and smooth that they can slip into a crevice in
the wall or floor with the utmost ease and facility. From their actions
it would seem that they were always on the alert, for when peril is
imminent they do not run aimlessly about for a place of security, but
know just where to find it with the least possible expenditure of time
and physical strength. Every nook and cranny of their appropriated
domain is as well known to these very humble of God’s creatures as some
forest-tract of country to one skilled in wood-craft. Never have I
studied the behavior of Lepisma that I have not been deeply impressed
with the intelligence of its actions. There have always been displayed
a purpose and an aim, which showed as plainly as could be that no blind
instinct was the cause of a conduct so rational and human-like.
YOU-EE-UP.
Hardly a person living in a sandy country district can be found who
has not seen or heard of the queer little insect called You-ee-up, a
name which the books do not give, and of which writers on entomological
subjects seem to be ignorant. The learned call him Myrmeleon, or
Ant-lion, and very appropriately too, because, like the great king of
beasts, he never attacks his prey in the open field, but by stratagem
while lying in wait in some hidden retreat or secret covert.
Should you chance, on a warm summer day, where sunny slopes abound on
the outskirts of a woods, or by the side of a frequented path or road,
look carefully about and soon will you descry a small funnel-like
opening, scarce two inches in depth and in width, upon a bare patch of
sand in the midst of an ocean of verdure. This little cavity is the
intentional work of the larva of the Ant-lion. A very close scrutiny
will show, by the presence of a pair of fierce jaws, the Ant-lion at
home.
Would you know the ingenious builder? Lift him out tenderly from his
burrow of sand, and when you have placed him upon the palm of your wide
open hand, note with the most careful exactness the peculiar make-up of
his structure, so that in the future you may have little difficulty in
recognizing him should you again meet.
His short, flat head, armed with powerful mandibles, heavy-set chest,
and large, soft, fleshy abdomen, amply protected on the sides with
stiff, bristly hairs, added to his compact, robust form, the forward
projection of his front and middle legs, and the backward prolongation
of the stronger and less movable hind ones, which eminently adapts
them to a backward manner of walking, are characters which so deeply
impress, that we cannot fail to call up, when occasion demands, the
possessor of so wonderful a mechanism.
[Illustration: YOU-EE-UP IN HIS DEN.
As He Appears in Youth and Old Age.]
Now that you have become familiar with the odd creature in form and in
mien, set him once more upon his proud realm of sand, and seat yourself
on the bank close by to watch and enjoy his curious behavior. In a
minute or two his fears will have subsided, and he in control again of
his accustomed indifference. See, he moves. Round and round he turns in
the loose grey sand, burying himself deeper and deeper, and throwing
the grains out from the hole he has made by his twistings, using his
short, flat head for a shovel. The sand, as it is thrown over the side
of the burrow, forms quite a margin, and when all is completed the
Ant-lion sinks himself deep into the bottom of the trap he has digged,
leaving only the tips of his mandibles in sight, which are extended and
ready to seize any insect that is so luckless as to fall into their
reach.
The unfortunate ant that ventures too close to the margin sets the sand
off rolling, and it immediately begins to struggle against falling
down, but the Ant-lion throws a few shovelfuls of sand against it, and
it soon comes tumbling down to the bottom of the funnel, when it is
instantly seized between the sharp mandibles in waiting, which, being
perforated by slender tubes, enable their blood-thirsty owner to suck
out its juices.
Country children, and adults as well, manifest a deep interest in
these strange beings. They call them, as has been intimated before,
You-ee-ups. How the name originated, and when, I do not pretend to
know, nor have I been able upon inquiry to find out from the oldest
inhabitants of the regions they affect. Old men and old women in the
seventies and eighties knew these insects by this name when they were
children, and I have been informed that they were always so spoken of
by _their_ fathers and mothers.
Even the insects themselves are believed to know the odd name by which
they are designated. So fixed is the belief in the minds of the many
that, to contradict it, is sure to subject the person so rash and
presumptuous to the grossest abuse from the friends of the strange
little creature. They have seen him in his sandy retreat, and have
called him by name, and he has never been known to decline a response.
“You-ee-up, you-ee-up,” cries one, with his mouth just over the
opening, and up comes the strange “crittur” as obedient as a lackey.
“You-ee-down, you-ee-down,” says the same childish voice, and down he
goes to his den to await, as is thought, the giving of further orders.
That the Ant-lion does seem to respond when called, cannot be denied,
for I have tried the experiment myself, and others have tried it in
my presence, and always with the same successful results. But people
go through the world not only with their eyes closed and their ears
sealed, but also with their minds forever locked against thinking,
lest, by thinking, they might do themselves serious injury. Had but
a little of thinking been done, or some common sense exercised, the
solution of the insect’s strange actions could have been reached
without any great difficulty.
Let me briefly explain. One cannot talk, as is well known, without some
motion being imparted to the outlying air. This moving air impinging
upon the loosely arranged sand piled up around the margin of the tiny
pitfall, dislodges some particles, and these, falling into the jaws
of the hidden Ant-lion, bring him to the surface, for he ascribes
the commotion to some ill-fated ant, or other such insect, that has,
in its anxious searching for food, tumbled unconsciously into his
artfully-laid trap. In a moment the mistake is discovered, and, with
all possible dispatch, he backs himself down into his den to await
further developments. His appearance on the occasion is greeted by
“you-ee-down, you-ee-down,” and as he goes down apparently in obedience
to the order, but really because it is a matter of business so to
do, it is claimed by the unlearned and unwise that his movements are
responsive to the command of the person by whom he is addressed.
Two years of larval life, and the subject of our sketch is lost to
the sight of the rural folks. A new life, where feeding is no longer
necessary, awaits him, but one in which the most radical changes must
occur if he is to fulfil the existence which nature designed in her
grand scheme of creation. From a silk-gland, which, unlike those of the
butterflies and moths, is situated at the end of the body, he spins
a cocoon, but there being so little of silk to spare, he needs must
supply the deficiency by the utilization of a quantity of sand, which
he glues into the walls of his house. Here he dwells a comparatively
inactive pupa for three brief weeks, retaining his large, powerful
mandibles to the last, which he uses in cutting his way out of the
cocoon, when he is ready to emerge as a winged neuropter. In the
adult form he resembles the dragon-flies in flight, flapping wildly
and irregularly about, as if his muscles were too weak to wield his
great stretch of wings. But in repose his alar appendages are folded
above each other, forming an acute-angled roof above the long, slender
abdomen. The antennæ or feelers are short, stout and club-shaped, and
the wings long, narrow and densely veined.
_Myrmeleon obsoletus_, a name given to this insect by Thomas Say, a
naturalist of repute, who lived in Philadelphia in the early half of
the present century, is by no means a rare species, if search is made
in the proper places. In the cut the larva is found to the right of
the burrow, while deep in the bottom, with the jaws only in view, is
another, prepared to receive the small ant just above should it lose
its foothold and tumble into the trap. On the wing, a little in the
background of the picture, may be seen the adult insect, represented in
hawking for prey over a meadowy expanse of country.
TOWER-BUILDING CICADA.
Closely allied to the bugs is a group of remarkable insects to which
naturalists now apply the name of Cicada, but which are generally,
though improperly, designated Locust by the common people. They are
readily distinguished by their broad heads, large prominent eyes,
with three eyelets triangularly placed between them, and delicately
transparent, veined wing-covers and wings. The abdomen is short and
pointed, and the legs are short, the anterior femora being much
thickened and toothed beneath. The hinder extremity of the body of
the female is conical, and the under-side has a longitudinal channel
for the reception of the ovipositor, or piercer, which is furthermore
protected by four short-grooved pieces which are immovably fixed to the
sides of the channel. The piercer itself consists of two outer parts
grooved on the inside and slightly enlarged and angular at the tips,
which are externally beset with small saw-like teeth, and a central
spear-pointed borer which plays between the other two, thus combining
the advantages of an awl and a double-edged saw, or rather of two
key-hole saws cutting opposite to each other. A hard, horny substance,
called chitine, the same as exists in the stings of bees and wasps, is
the material of its composition. It would be impossible to conceive
of anything more exactly fitted for its required uses than is this
beautiful complicated instrument.