This book is designed to make the reader acquainted with the common
spiders most likely to be found over a large part of the United States
as far south as Georgia and as far west as the Rocky Mountains. Local
collections show that in the neighborhood of any city in the country
there are at least three or four hundred species of spiders; but few
such collections have been made, and it is not yet possible to tell all
the kinds of spiders that live in any particular place, or how far any
species extends over the country. The species which are here described
and figured are all of them well known and have been described in other
books. Rare and doubtful species are omitted, though some of these may
in time prove to be among the most common. A large number of spiders are
too small to be easily seen, and most of these are omitted, only a few
representative species being described. Spiders have, unfortunately, no
common names, except such indefinite ones as "the garden spider," "the
black spider," "the jumping spider," and the like. Even "tarantula" has
become only a nickname for any large spider. The names of spiders, like
those of other animals, have been given to them independently by
different persons, so that many of them have more than one name, and the
more common the spider the larger the number of names. In this book only
one name is usually given to each species, and the name used is one that
has been published with a description of the species in some other
well-known book. Readers who are interested in the names of species and
in comparing the classifications of different naturalists are referred
to a "Catalogue of the Described Araneæ Of Temperate North America," by
George Marx, in the _Proceedings of the United States National Museum_,
1890, which is a useful index to what has been published on American
spiders.
The front half of a spider's body, called the cephalothorax, contains in
one piece the head and thorax, the only outward division between them
being shallow grooves from the middle of the back to the front legs. In
the middle of the cephalothorax is usually a groove or depression, under
which, inside, is a muscle that moves the sucking apparatus by which
food is drawn into the mouth. At the sides of the thoracic part are four
pairs of legs, and on the head part are a pair of palpi and a pair of
mandibles. The legs have seven joints: (1) the coxa, the thick basal
joint, having little motion; (2) the trochanter, a short joint moving
very freely on the end of the coxa; (3) the femur, the largest joint of
the leg, moving with the trochanter in all directions; (4) the patella,
moving up and down on the end of the femur; (5) the tibia, joined
closely to the patella and moving with it up and down; (6) the
metatarsus; and (7) the tarsus, moving together on the end of the tibia.
The palpi are like small legs and have one less joint than the walking
legs. The mandibles are close together at the front of the head (fig.
2). They are two-jointed, the basal joint stout and the end joint or
claw slender and sharp-pointed. The claw has near its point a small
hole, which is the outlet of the poison gland. The poison kills or
disables the insects which are captured by the spider. Its effect on the
human skin varies in different persons; sometimes it has no effect at
all; oftener it causes some soreness and itching like the stings of
mosquitoes and bees, and cases have been known in which it caused
serious inflammation which lasted a long time. Spiders seldom bite, and
only in defense, the bites so commonly charged to them being often the
work of other animals.
[Illustration: FIG. 1. Diagram of the under side of a spider, with the
legs removed except one.]
[Illustration: FIG. 2. Front of head, showing the eyes and mandibles.]
On the front of the head are the eyes, usually eight in number,
differing in size and arrangement according to the kind of spider. The
sight of spiders is distinct for only short distances. Spiders of middle
size can see each other, and the insects which they eat, at a distance
of four or five inches, but beyond that do not seem to see anything
clearly. At the ends of the feet are two claws, curved and with teeth
along the inner edge, and in many spiders there is a third shorter claw
between them (fig. 212). The claws are sometimes surrounded by a brush
of flattened hairs (figs. 104, 114). The basal joints of the palpi are
flattened and have their inner edges extended forward so that they can
be used as jaws to press or chew the food. These are called the maxillæ.
Between the maxillæ is a small piece called the labium, and between the
legs is a larger oval piece called the sternum.
The hinder half of the body, the abdomen, is connected with the
cephalothorax by a narrow stem (fig. 1). It has at the hinder end the
spinnerets, three pairs of appendages having at their ends a great
number of microscopic tubes through which the thread is drawn out. When
not in use the spinnerets are folded together, so that the smaller inner
pair are concealed.
The thread of spiders resembles that spun by caterpillars in making
their cocoons, and can be manufactured in the same way into silk cloth.
The spider's thread is composed of a great number of finer threads
passing from the body through separate tubes and uniting into one before
they have time to dry. This can be seen by examining the attachments of
spiders' threads to glass. All the spinning tubes are not alike, but on
certain parts of the spinnerets are larger or differently shaped tubes,
and these are the outlets of glands of different kinds in the spider's
abdomen, and are used in making different kinds of threads for certain
parts of the webs, nests, or cocoons.
In front of the spinnerets on the under side is a small opening to the
tracheæ, or air-tubes (fig. 1). At the front of the abdomen on the under
side is a transverse fold of the skin, at the ends of which are the
openings of the air-sacs or lungs, and between them the opening of the
reproductive organs (fig. 1). The latter is covered in females by an
apparatus, sometimes large and complicated, called the epigynum. Its
presence shows that the female is full grown. Young spiders do not have
it. Male spiders have the ends of the palpi enlarged, and under the
terminal joint what is known as the palpal organ, sometimes very
complicated in shape. The presence of these organs shows that the male
is full grown. Young males that have nearly reached maturity have the
ends of the palpi simply enlarged. Male spiders almost always have the
body smaller and the legs longer than females of the same species.
The colors of spiders are partly in the skin itself and partly in the
hairs and scales that cover it. Almost all spiders are covered with hair
of some kind, but in some species it is so fine and short that it has
little effect on the color. In others the skin is entirely covered with
hairs of various lengths and sometimes with scales somewhat like those
of butterflies, flattened and feathered or toothed on the edges. The
colors of spiders are very varied, and in many species, especially of
the jumping spiders, as brilliant as those of butterflies. The most
common colors are grays and browns, resembling the ground or plants and
stones among which the spiders live. Sometimes the color is uniform all
over the body, except that it is a little darker toward the head and the
ends of the feet. The most common marking is a spot on the front of the
abdomen over the spider's heart, sometimes merely a translucent part of
the skin and sometimes a definite color spot darker in the middle and
outlined with a lighter shade or white. The hinder half of the abdomen
is often marked with several pairs of spots, becoming smaller toward the
end, and these spots may be united into a pair of stripes or a more
complicated pattern. (See figures.) The legs are often marked with rings
of color, almost always at the ends of the joints. Besides these common
markings there are in some spiders strong contrasts of color, such as
bright red or yellow spots on a black ground. In the males, especially
among the Attidæ, there are often shining scales that reflect different
colors in a bright light, and tufts of black or white hairs about the
head and front legs.
Spiders live in all kinds of places. Certain species are attached to
houses and seldom found far from them, and many of these occur over a
large part of the world. The light webs in the corners of rooms are
chiefly the work of _Theridium tepidariorum_ (p. 112), occasionally of
_Steatoda borealis_ (p. 119) and _Steatoda triangulosa_ (p. 121). In
cellars the thin webs about the stairs and shelves are those of the
long-legged _Pholcus phalangioides_ (p. 129) or of _Linyphia nebulosa_
or _minuta_ (pp. 144, 145), and the thick flat webs in corners and
between the beams are those of _Tegenaria derhamii_ (p. 96). On the
outside of houses live two jumping spiders, the most common being
_Epiblemum scenicum_ (p. 60), a small gray species the color of
weathered wood, and the other, _Marptusa familiaris_ (p. 61). Some of
the round-web spiders live in great numbers about houses. The three
brown species, _Epeira sclopetaria_ (p. 160), _patagiata_, and _strix_,
hide in cracks and at night make their round webs in porches, barns, and
bridges. In the northern part of the country _Epeira cinerea_ (p. 165)
has the same habit. _Epeira globosa_ (p. 174) is often found on the
outside of houses, and so are _Zilla atrica_ and _Zilla x-notata_ (p.
185). _Amaurobius ferox_ (p. 215), a large imported species, is
sometimes found in cellars, and several Dictyna (p. 206) live in great
numbers on the outside of houses, in corners of windows, under the edges
of shingles, or in cracks of walls, spreading their webs wherever there
is room for them and gathering dust so that they often make a distinct
spot on the wall. In the southern states _Filistata hibernalis_ (p. 220)
is one of the most common spiders about houses. Its webs often make a
round spot of dust a foot or more in diameter. Stones and sticks lying
on the ground furnish shelter for a great number of spiders. _Steatoda
borealis_ (p. 119), _marmorata_ (p. 121), and _guttata_ (p. 120) and
_Asagena americana_ (p. 122) are found in such places, and so,
especially in the South, is _Latrodectus mactans_ (p. 122). The large
jumping spiders, _Phidippus mystaceus_ (p. 50) and _tripunctatus_ (p.
51), make large nests of white silk under stones near the ground. The
ground spiders, _Drassus saccatus_ (p. 6), _Gnaphosa conspersa_ (p. 2),
and _Prosthesima atra_ (p. 5), run on the ground and hide under stones.
_Lycosa nidicola_ (p. 69), _Lycosa communis_ (p. 75), _Lycosa pratensis_
(p. 69), _polita_ (p. 70), and _cinerea_ (p. 74) are often found under
shelters of this kind. The crab spiders of the genus Xysticus live under
stones, but oftener under bark farther from the ground.
In the summer, plants of all kinds from grass to trees are full of
spiders. The Lycosas (pp. 68 to 84) run among the short grass. The small
species of Linyphia (p. 134) and Erigone (p. 148) make their flat webs
close to the ground among small plants. _Linyphia marginata_,
_communis_, _coccinea_, and _phrygiana_ make theirs among plants and
rocks, a foot or two above the ground. The Theridiums (p. 110) live
between leaves and on the ends of twigs, covering them with webs that
only show when the dew is on them. _Agalena nævia_ (pp. 91 to 95) makes
its flat webs on the grass and anywhere else where it can find a place
to fasten them. The jumping spiders (p. 41) run about for their prey on
plants, and some of them have silk nests among the leaves. The Misumenas
(p. 25) live among flowers and wait for insects to alight within reach.
The webs of Dictyna (p. 206) are commonest on the ends of grass and
twigs, and are known by the dust that they gather. The round-web spiders
mature in the middle of the summer, and then _Epeira trivittata_ (p.
166) is found on all kinds of bushes and grass, and later _Epeira
insularis_ (p. 169) and _Epeira trifolium_ (p. 171) in hidden nests near
their webs. _Epeira angulata_, _sylvatica_, and _nordmanni_ (p. 162)
live among bushes and trees. _Cyclosa conica_ (p. 183), _Acrosoma
spinea_ (p. 190), and Uloborus (p. 216) live among low bushes in
openings of the woods. Hyptiotes (p. 218) lives among the lower dead
branches of pines, perching on the end of a twig which it exactly
matches in color.
The marshes are the home of great numbers of spiders. The Tetragnathas
(p. 198) live there, especially along the streams and ditches. _Epeira
gibberosa_ (p. 175) and _placida_ (p. 176) make their horizontal and
oblique webs among the tall grass in open places. The two species of
Argiope (pp. 193 to 198) swarm in marshes and open fields and in autumn
become conspicuous by their size and bright colors, and when they
disappear leave over winter their brown cocoons (pp. 197, 200) fastened
to the grass.
The moss and dead leaves in the woods are alive with spiders; even in
summer some species always live there, and in winter the young of those
that in warm weather live among the bushes find shelter where they can
remain torpid through the cold season without freezing.
The eggs of spiders are covered with silk, forming a cocoon which varies
much in shape and color in different species. Some spiders hang it in
the web, others attach it to plants or stones, and others carry it about
with them either in the mandibles or attached behind to the spinnerets.
The young remain in the cocoon until they are able to run about, and
after coming out of the cocoon keep together for a short time, sometimes
in a web which they make in common, sometimes in a nest made by the
mother, and in some species on the mother's back, but they soon scatter
and hunt their own food or make cobwebs, according to the habits of the
species.
Different kinds of spiders mature and breed at different times of the
year, most of them living only one season. Those that mature late, like
_Agalena nævia_ and Argiope, pass the winter as eggs, while those that
mature early, like _Epeira sclopetaria_ and _Lycosa nidicola_, pass the
winter half grown. Some species, like _Theridium tepidariorum_ (p. 112),
breed several times in the year, and old and young are found at all
seasons.
The spiders are naturally divided into two groups of families: (1) the
hunting spiders, which run on the ground or on plants, catching insects
wherever they find them, or waiting among leaves and flowers until
insects come within their reach; (2) the cobweb spiders, which make webs
to catch insects and live all the time in the web or in a nest near it.
The hunting spiders include: (1) the Dysderidæ (p. 22), a few species
with six eyes only and with four breathing holes at the front end of the
abdomen; (2) the Drassidæ (p. 1), or ground spiders, which live among
stones and dead leaves or among plants, making tubular nests and flat
egg cocoons but no cobwebs; (3) the Thomisidæ (p. 24), the flat and
crab-like spiders living on plants or under bark and stones; (4) the
Attidæ (p. 41), the jumping spiders, with wide heads and large front
eyes, many of them brightly colored and active in their habits; (5) the
Lycosidæ (p. 67), the long-legged running spiders, living on the ground
and, a few of them, in holes and carrying about their round egg cocoons
attached to the spinnerets.
The cobweb spiders include: (1) the Agalenidæ (p. 91), making flat webs
on grass or in corners of houses, with a tube at one side in which the
spider lives; (2) the Therididæ (p. 107), round spiders with flat or
irregular webs in corners and on plants; (3) the Linyphiadæ (p. 134),
with flat webs, small spiders of a great number of species living near
the ground and in shady places; (4) the Epeiridæ (p. 154), the round
web spiders; (5) the Cribellata, having a calamistrum (see p. 205) on
the hind legs and making rough webs that gather dust.
Cobwebs are of four principal kinds:
1. The flat webs, closely woven of long threads crossed by finer ones in
all directions and connected with a tubular nest where the spider hides,
and from which it runs out on the upper side of the web after insects
that may fall upon it. These are made by Agalena and Tegenaria (pp. 91
to 104).
2. The net-like webs, made of smooth threads in large meshes, sometimes
in a flat or curved sheet held out by threads in all directions. The
spider lives on the under side, back downward. These are made by
Therididæ and Linyphiadæ (pp. 107, 134).
3. The round webs, made of threads radiating from a common center and
crossed by circular loops and spirals, part of which are adhesive.
4. The webs of the Ciniflonidæ, composed in part of loose bands of silk
(p. 205).
The simplest and best way to preserve spiders for examination is to put
them in alcohol. It kills them immediately and keeps their form and
markings and, to a great extent, their colors. They may be kept alive
for a few days in glass bottles or jars. It is not necessary to make
holes in the covers, or to feed the spiders often. They need water, and
this can be furnished them conveniently by putting a piece of wet paper
or rag in the bottle.
If one wishes to find what spiders live in his neighborhood, they must
be looked for at all times and in all kinds of places. The house and
cellar should be looked over and the spiders watched until they are
fully grown. The outside of the house and fences should be looked over
occasionally in the same way, only those spiders being taken that are
full grown, unless they are of new or rare kinds. A great many spiders
may be found on the garden fences of a shady street, especially in the
early summer and again in the autumn. At both seasons they are more
active in the middle of the day and more likely then to be wandering
about. The writer always carries two small bottles, one a common
homeopathic medicine vial, holding one or two drams and half full of
alcohol, the other a straight tube vial, without any neck and about the
same size, that is kept always dry and occasionally wiped out to remove
the threads that are made in it. The dry bottle is placed quickly over
the spider and moved about until the spider is coaxed to go into it. The
bottle is then turned up and closed with a finger until the other bottle
can be uncorked and the spider shaken into the alcohol. In the fields
and along the country roads the stones and sticks that have been lying
for some time on the ground should be carefully lifted and searched,
both on the under surface and on the ground below. The stones and sticks
should be turned back into the same places so that other spiders may
find at once comfortable places to hide under. If they are dropped on
new ground, it may be a year before they are fit to use again. Among
trees and shrubs the best things are to be found by moving slowly about
and watching for spiders, nests, and cobwebs without disturbing them.
The webs can be best seen when moving toward the light. The greatest
number of spiders can usually be found along paths and the edges of
woods, and paths through the woods are the best places for many ground
spiders.
Spiders should be looked for in the same way in grass, by creeping along
on the ground or by sitting down and watching until something walks into
view; or the grass and weeds may be swept with a cotton bag, fastened on
a hoop like a dip net, with a short handle, and the spiders picked out
with a dry bottle from among the leaves and insects that will be
gathered with them. Bushes may be swept in the same way, or may be
shaken over an open umbrella, or a piece of cloth or paper. In winter,
when spiders are torpid, great numbers can be found by sifting the dead
leaves that have been lying for some years in the woods. A common coal
sieve is fine enough to hold the leaves while the spiders and sticks and
dirt pass through, and may be picked over on a cloth or carried home in
a bag and examined in the house. The sifting should be repeated several
times, as many of the spiders hold to threads among the leaves and
become loosened only after much shaking.
In the following pages a general description is given of each family,
followed by descriptions of the species belonging to it, with a figure
of each species placed as near as possible to the description. In some
cases, where the genera are large and well defined, separate
descriptions are given of each genus, but where the genus is not easy to
distinguish or represented by only a few species, there is no separate
generic description, and the species are placed next to those of other
genera to which they are most closely related. If the names of spiders
are known, they can readily be found by the index at the end of the
book. If information is sought about an unknown spider, the
illustrations through the book furnish the most convenient index, as the
general form and proportions of spiders and the arrangement of their
eyes usually show to what family they belong. The ground spiders and
those without cobwebs are described first, and the sedentary species
living in webs in the last half of the book. Readers unfamiliar with the
subject are advised to read first the descriptions of the families and
compare with them the spiders that they find in their own neighborhoods.
The figures are in most cases enlarged for the sake of distinctness, and
spiders of much smaller size must be looked for.