ARACHNIDA EMBOLOBRANCHIATA (_CONTINUED_)—ARANEAE (_CONTINUED_)—
CLASSIFICATION
The systematic study of Spiders has hitherto presented very great
difficulties. There is an extensive literature on the subject, but the
more important works are costly, not commonly to be found in libraries,
and written in diverse languages. Moreover, the nomenclature is only now
emerging from a condition of chaos. Able and diligent Arachnologists
have done admirable work in studying and describing the Spider fauna of
their various countries, and occasional tentative suggestions have been
put forth with a view to reducing to some sort of order the vast mass of
heterogeneous material thus collected. Most schemes of classification,
based chiefly upon a knowledge of European forms, have proved quite
inadequate for the reception of the vast numbers of strange exotic
species with which recent years have made us acquainted. The number of
described species is very large, and is rapidly increasing; but though
we are very far indeed from anything like an exhaustive knowledge of
existing forms, it may now be said that almost every considerable area
of the earth’s surface is at least partially represented in the cabinets
of collectors, and it is possible to take a comprehensive view of the
whole Spider fauna, and to suggest a scheme of classification very much
less likely than heretofore to be fundamentally deranged by new
discoveries.
The first to apply the Linnaean nomenclature to Spiders was Clerck, in
his _Araneae Suecicae_ (1757), which gives an account of seventy
spiders, some of which are varieties of the same species. A few new
species were added by Linnaeus, De Geer, Scopoli, Fabricius, etc., but
the next work of real importance was that of Westring (1861), who, under
the same title, described 308 species, divided among six families.
Blackwall’s beautiful work, the _Spiders of Great Britain and Ireland_,
was published by the Ray Society in 1864. He divides spiders into three
tribes, Octonoculina, Senoculina, and Binoculina, according to the
number of the eyes, and describes 304 British species, distributed among
eleven families.
His successor in this country has been Pickard-Cambridge, whose work,
under the modest title of _The Spiders of Dorset_ (1879–81), is
indispensable to British collectors.
Blackwall’s division of the order into tribes was evidently artificial,
and has not been followed by later Arachnologists. Dufour (1820) founded
two sub-orders, Dipneumones and Tetrapneumones, based on the presence of
two or four pulmonary sacs. Latreille (1825) established, and many
Arachnologists adopted, a division into tribes based upon habits,
Orbitelariae, Retitelariae, Citigradae, Latigradae, etc., and this
method of classification was followed in the important work of Menge,
entitled _Preussische Spinnen_, which was published between 1866 and
1874.
Since 1870 determined efforts have been made to grapple with the
difficult subject of Spider classification, notably by Thorell and
Simon. The latter, undoubtedly the foremost living Arachnologist, writes
with especial authority, and it is inevitable that he should be largely
followed by students of Arachnology, who cannot pretend to anything like
the same width of outlook.
It is indicative of the transition stage through which the subject is
passing that Simon in his two most important works,[306] propounds
somewhat different schemes of classification, while in the _Histoire
naturelle_, where his latest views are to be found, he introduces in the
course of the work quite considerable modifications of the scheme set
forth in the first volume.
In that work the order is divided into two sub-orders, ARANEAE
THERAPHOSAE and ARANEAE VERAE, the first sub-order containing
_Liphistius_ and the Mygalidae or Theraphosidae of other authors, while
all other spiders fall under the second sub-order. The Araneae verae are
subdivided into CRIBELLATAE and ECRIBELLATAE, according to the presence
or absence of “cribellum” and “calamistrum” (see p. 326) in the female.
Important as these organs doubtless are, the Cribellatae do not appear
to form a natural group, some of the families having apparently much
closer affinities with certain of the Ecribellatae than with one
another. This is especially evident in the case of the cribellate
Oecobiidae and the ecribellate Urocteidae (see p. 392), which most
authors unite in a single family.
After all, the larger divisions of the order are not of great
importance, and in the present chapter Simon’s linear arrangement of
families will in the main be followed, except for the distribution of
the eight families which constitute his Cribellatae[307] to the
positions which a more general view of their structure would seem to
indicate.
=Fam. 1. Liphistiidae.=—_Spiders with segmented abdomen, as shown by the
presence of a series of tergal plates. Eight spinnerets in the middle of
the ventral surface of the abdomen, far removed from the anal tubercle.
Sternum long and narrow. Eight compact eyes on a small eminence. Four
pulmonary stigmata._
[Illustration:
FIG. 201.—Profile (nat. size) and ocular area (enlarged) of
_Liphistius desultor_.
]
This Family includes a single genus and two species of large spiders
(about two inches in length), one from Penang and one from Sumatra. Very
few examples have been found, and these are more or less defective and
in bad condition. In some respects, especially the distinct segmentation
of the abdomen, this genus much more nearly approaches the Pedipalpi
than do any others of the order. No other spider possesses more than six
spinning mammillae, but it is possible that eight was the more primitive
number, and that the “cribellum” (see p. 326) of the so-called
Cribellate spiders is derived from the pair now possessed by
_Liphistius_ alone.
Some Arachnologists consider the genus _Liphistius_ so different from
all other spiders as to constitute in itself a sub-order, for which, on
account of the position of its spinnerets, the name MESOTHELAE has been
suggested, all other forms falling into the sub-order OPISTHOTHELAE.
=Fam. 2. Aviculariidae. (Mygalidae).=[308]—_Spiders with independent
chelicerae, the paturon directed forward and the unguis or fang
articulating in a vertical plane. The eyes are eight (except_ Masteria,
_six), usually compact, and situated on an eminence. Pedipalpi very
leg-like, and palpal organs of male simple. No maxillae. Four pulmonary
stigmata. Spinnerets normally four. No colulus._
The Aviculariidae inhabit the warmer portions of the world, and are
entirely unrepresented in this country. The monster spiders which excite
wonder in zoological collections belong to this group, as do the
moderate-sized “Trap-door” Spiders which are found abundantly in the
Mediterranean region.
The Family has been divided into about a hundred and fifty genera,
nearly half of which, however, contain only a single species.
They have been grouped by Simon[309] into seven sub-families,
PARATROPIDINAE, ACTINOPODINAE, MIGINAE, CTENIZINAE, BARYCHELINAE,
AVICULARIINAE, and DIPLURINAE, of which the first three may be dealt
with very briefly.
(i.) The PARATROPIDINAE include only two American species, _Paratropis
scrupea_ from the Amazon, and _Anisaspis bacillifera_ from St. Vincent.
They have thick, rugose integuments, and the internal angle of the coxa
of the pedipalp is produced. The labium is fused with the sternum, which
is very broad. Nothing is known of their habits, but as they do not
possess a “rastellus” (see p. 320) they are probably not burrowing
spiders.
(ii.) The ACTINOPODINAE comprise three genera, _Stasinopus_ represented
by a single South African species, _S. caffrus_; _Eriodon_, of which
about ten species inhabit Australia; and _Actinopus_, of which about ten
species are found in Central and South America. They have the coxae of
the pedipalps very short and broad, and somewhat produced at the
internal angle. The eyes are not in the usual compact group, but are
somewhat extended across the caput. _Actinopus_ burrows a deep
cylindrical hole lined with silk, and furnished with a round, bevelled
trap-door.
(iii.) The sub-family MIGINAE is established for the reception of three
genera, _Moggridgea_ (South Africa), _Migas_ (Australia and South-West
Africa), and _Myrtale_, whose single species, _M. perroti_, inhabits
Madagascar. They are chiefly characterised by their very short and
downwardly-directed chelicerae. They are not terricolous, but inhabit
trees, either boring holes in the bark, or constructing a sort of silken
retreat fortified by particles of wood.
(iv.) The CTENIZINAE form a large group, including some forty genera.
All the “Trap-door” Spiders of the Continent fall under this sub-family,
which, moreover, has representatives in all the tropical and
sub-tropical regions of the world. A rastellus is always present, and
the eyes form a compact group on an eminence. The coxae of the pedipalps
are longer than in the groups previously mentioned, and there is no
production of the internal angle. The labium is generally free.
The commonest European genus is _Nemesia_, of which about thirty species
inhabit the Mediterranean region. The cephalothorax is rather flat, and
the central fovea is recurved (◠). The burrow is sometimes simple and
sometimes branched, and the trap-door may be either thin, or thick with
bevelled edges.
Allied genera are _Hermacha_ and _Rachias_ in South America,
_Spiroctenus_ in South Africa, _Genysa_ in Madagascar, _Scalidognathus_
in Ceylon, and _Arbanitis_ in New Zealand. The genus Cteniza (fovea
procurved ◡) possesses only a single species (_C. sauvagei_), found in
South-East France and Italy.
_Pachylomerus_ is a widely-distributed genus, being represented in North
and South America, Japan, and North Africa. The tibiae of the third pair
of legs are marked above by a deep impression near the base. A closely
allied genus, _Conothele_. inhabits Southern Asia and New Guinea.
The widely-distributed genus _Acanthodon_, which has representatives in
all the sub-tropical countries of the world, together with the South
American genera _Idiops_ and _Pseudidiops_, and the Indian genus
_Heligmonerus_, present a peculiar arrangement of the eyes, one pair
being situated close together in the middle of the front of the caput,
while the remaining six form a more or less compact group some distance
behind them.
Among the many other genera of the Ctenizinae may be mentioned
_Cyrtauchenius_, of which many species inhabit North-West Africa, and
its close ally _Amblyocarenum_, represented on both shores of the
Mediterranean, and in North and South America. They differ from
_Cteniza_ chiefly in the possession of strong scopulae on the tarsi and
metatarsi of the first pair of legs, and in the double row of teeth with
which the tarsal claws are furnished. Their burrows are often surmounted
by a sort of turret raised above the level of the ground.
(v.) The BARYCHELINAE are burrowing forms which resemble _Nemesia_, but
have only two tarsal claws. _Leptopelma_ is the only European genus, and
has close affinities with certain South American genera (_Psalistops_,
_Euthycoelus_, etc.). _Pisenor_ inhabits tropical Africa, and
_Diplothele_, unique in possessing only two spinning mammillae, is an
inhabitant of India.
(vi.) The AVICULARIINAE include all the large hairy spiders which are
commonly called _Mygale_. The genus _Phlogius_, which inhabits Southern
Asia, forms a lidless burrow, though it has no rastellus, but
practically all the other members of the group are non-terricolous,
living under stones or in holes in trees, where they weave a slight web.
They are nocturnal in their habits. They all possess two tarsal claws,
and the labium is free and spined at the tip. Of the four spinnerets the
posterior pair are long and three-jointed, while the anterior are short
and not very close together.
The particular form of the tarsi and the nature of the scopulae,[310]
“claw-tufts,” and spines upon them are of great importance in
distinguishing the members of this group.
The Aviculariinae comprise about sixty genera from all the tropical and
sub-tropical regions of the world.
The genus _Ischnocolus_ extends into the Mediterranean region, having
representatives besides in Southern Asia and in Central and South
America. All the tarsi have their scopulae divided longitudinally by a
band of hairs. _Chaetopelma_ inhabits Egypt, Syria, and Arabia, and
_Cyclosternum_ is found in West Africa as well as in Central and South
America. In these genera the scopulae of the last two pairs of legs are
alone divided. The largest known spider is _Theraphosa leblondi_, which
is a native of Guiana. It measures 9 cm. (about three and a half inches)
in length.
_Eurypelma_ is a genus of large spiders entirely confined to the New
World, where it possesses many species. The genus _Avicularia_ is also
American, and includes a number of large long-haired spiders with short
and very strong legs, on which the scopulae and claw-tufts are well
developed. Its nearest allies in the Old World are the Indian genus
_Poecilotheria_, and the West African genus _Scodra_. The stridulating
spider figured on p. 328 belongs to this group, _Chilobrachys_ being a
genus from Ceylon.
[Illustration:
FIG. 202.—_Ischnothele dumicola_, ♀ × 2. (After Pocock.)
]
(vii.) The DIPLURINAE are a very aberrant group, including some twenty
genera of Aviculariidae, usually of medium size, and possessed, as a
rule, of very long posterior spinnerets. They do not burrow or live in
holes or under stones, but weave webs of close texture, much resembling
those characteristic of the Agelenidae (see p. 415). The tarsal claws
are three in number, and there are never any claw-tufts. The rastellus,
of course, is absent.
Two genera have representatives in Europe, _Brachythele_ inhabiting the
East Mediterranean region (as well as many other parts of the world),
while _Macrothele_ is found in Spain as well as in the Malay Peninsula
and New Zealand. _Ischnothele dumicola_ is a native of Western India.
_Diplura_ is a South American genus. _Trechona venosa_, a large species
remarkable for the orange bands which decorate its abdomen, is also a
native of South America. The New Zealand genus _Hexathele_, and the
genus _Scotinoecus_ from Chili, possess six spinnerets. _Masteria_
(Ovalan Island) and _Accola_ (Philippines and South America) differ from
the rest of the family in having only six eyes.
=Fam. 3. Atypidae.=—_Spiders with anteriorly projecting and vertically
articulating chelicerae, but with no trough on the paturon for the
reception of the unguis, which is guarded when closed by a single row of
teeth. The spinnerets are normally six, and the anal tubercle is above,
and well removed from the posterior spinnerets._
[Illustration:
FIG. 203.—_Atypus affinis_, ♀.
]
The Atypidae are a small family of six genera, rather closely related to
the Aviculariidae, and by some Arachnologists incorporated with them.
They may be regarded as the representatives of that family in
sub-tropical and temperate regions. In form they are strongly built,
with smooth integuments, and their legs are short and powerful. Of the
twenty-four species hitherto described almost all belong to the northern
hemisphere. Five are natives of Europe, and two are included in the
English fauna. The best known is _Atypus affinis_, which has been found
in several localities in the south of England, and which has occurred on
the Devil’s Dyke, near Cambridge. The female measures about half an inch
in length, the male being smaller. It burrows a deep cylindrical hole at
the edge of a grassy or heathery bank and lines it with a loose tube of
silk, which extends considerably beyond the orifice of the burrow,
either lying flat on the ground, or raised up and attached to the
neighbouring herbage. There is no lid, but the upper end of the tube is
always found closed, whether by its elasticity or by the deliberate
operation of the spider is not known. The animal is nocturnal in its
habits. Another species, _A. beckii_, occurs very rarely in the south of
England.
The genus _Atypus_ has representatives in Central and South Europe,
North Africa, Japan, Java, and North America. Of the other genera,
_Calommata_ inhabits Central and South-East Asia and Japan,
_Brachybothrium_, _Atypoides_, and _Hexura_ are peculiar to North
America, while _Mecicobothrium_ comprises a single species (_M.
thorelli_) native to the Argentine.[311]
=Fam. 4. Filistatidae.=—_Cribellate Spiders of moderate size, usually
brown or yellow in colour, with smooth integuments and somewhat long
tapering legs. The eight eyes are compactly arranged, and the palpal
organs of the male are of simple structure. The six spinnerets are
short, the anterior pair being thick and separated. Two pulmonary sacs,
with two minute tracheal stigmata close behind them and widely
separate._
There is but one genus, _Filistata_, in this family. About fifteen
species have been described, five of which inhabit the Mediterranean
region. Three are found in America, and others inhabit Central Asia, the
Philippines, and Australia. The genus is not represented in this
country, but one species, _F. testacea_, has an extremely wide
distribution in the Old World, while _F. capitata_ extends throughout
the American continent.
The calamistrum of the female is short, only occupying a portion of the
metatarsus of the fourth leg. The cribellum is divided. These spiders
weave a web of close texture, of an irregular tubular form.
=Fam. 5. Oecobiidae (Urocteidae).=—Two very remarkable genera constitute
this family, _Oecobius_ and _Uroctea_.
The species of _Oecobius_, about fifteen in number, are small spiders,
inhabiting sub-tropical countries—and especially desert regions—and
spinning a slight web under stones, or in holes in walls. The female
possesses a small transverse cribellum, the two halves of which are
widely separated. The calamistrum is but feebly developed. No example
has occurred in this country, but nine species have been described in
the Mediterranean region.
[Illustration:
FIG. 204.—=A=, _Oecobius maculatus_, much enlarged; =B=, _Uroctea
durandi_, slightly enlarged. (After Simon.)
]
The three species of _Uroctea_ are rather large spiders, two being
native to Africa, while the third inhabits China and Japan. They are
ecribellate. These two genera very closely resemble each other, not only
superficially, but in certain structural details—notably the remarkably
developed and two-jointed anal tubercle—and their close affinity
supplies the strongest argument against separating the spiders which
possess cribellum and calamistrum into a group by themselves. In both
genera the cephalothorax is very broad and rounded at the sides. The
eight eyes are compactly arranged. The sternum is broad and
heart-shaped. The legs are nearly of equal length, and the posterior
spinnerets have very long terminal joints.
=Fam. 6. Sicariidae (Scytodidae).=—The Sicariidae are a small group of
six-eyed spiders, usually with weak legs and slow halting movements;
they live under stones or in outhouses. The cephalothorax is generally
smooth and devoid of the median fovea, and the palpal organs of the male
are extremely simple. The best known genus is _Scytodes_, one species of
which (_S. thoracica_) has on rare occasions been found in outhouses in
the south of England, in Dorsetshire, and Kent. This is a remarkable
spider, about one-third of an inch long, with a pale yellow
ground-colour, marked with black spots and patches. The cephalothorax is
smooth and dome-shaped, and highest near the posterior end.
All the other members of the family are exotic. _Loxosceles_ is found in
the Mediterranean region and all over America, as well as in Japan. The
median fovea is present in this genus. _Sicarius_ is a native of America
and South Africa. It is of stouter build than _Scytodes_, and the legs
are stronger. _Drymusa_ belongs to South Africa. The peculiar New
Zealand species _Periegops hirsutus_ is placed by Simon in this family,
as is also the North American genus _Plectreurys_, notwithstanding its
possession of eight eyes.
=Fam. 7. Hypochilidae.=—Two species only are included in this family,
_Hypochilus thorelli_ of North America, and _Ectatosticta davidi_, a
native of China. They have four pulmonary sacs, though they possess
little else in common with the “Theraphosae.” The pedipalpus of the male
is very remarkable, the tarsus being almost unmodified, and the very
small palpal organ being inserted at its extremity. These spiders are
cribellate.
=Fam. 8. Leptonetidae.=—The Leptonetidae are small spiders with smooth
and usually dull-coloured integuments. Most of them are cave-living, but
some are found amidst vegetable débris in damp spots in forests. The
eyes are six in number, and the legs are generally long and thin. There
are five genera. _Leptoneta_ has about ten species living in caves in
the Pyrenees. The single species of _Telema_ (_T. tenella_) has the same
habitat. _Ochyrocera_ has representatives in tropical Asia and America,
and is somewhat more ornate than most members of the group. _Usofila_
has a single species, inhabiting North America, while _Theotina_ is
found in caves in the Philippines and in Venezuela.
=Fam. 9. Oonopidae.=—The Oonopidae are very small spiders, seldom
exceeding 2 mm. in length (the largest 4 mm.), living among vegetable
débris. _Oonops pulcher_, the only English representative of the family,
is not rare under stones or in the débris at the bottom of hedges. It is
a small brick-red spider, easily recognised by its six comparatively
large oval eyes, which are pale-coloured, and occupy the whole of the
caput.
The minute spiders of this family were until recently overlooked by
collectors in foreign countries, but now more than a hundred species
have been described, belonging to some eighteen genera. Thirteen species
inhabit the Mediterranean region, occurring especially on the African
side. In several genera there is a “scutum” or hard plate on the
abdomen. This is the case with _Dysderina_, which has a wide
distribution, as have also _Ischnyothyreus_ and _Opopaea_, and the
non-scutate genus _Orchestina_.
=Fam. 10. Hadrotarsidae.=—This family contains only two species,
_Hadrotarsus babirusa_ from New Guinea, and _Gmogala scarabeus_ from
Sydney. In general appearance they resemble the scutate Oonopidae, but
they have eight eyes, curiously arranged, two large, somewhat triangular
eyes being situated near the middle of the cephalothorax, and two groups
of three small eyes on either side of the front part of the caput. These
spiders are very minute.
=Fam. 11. Dysderidae.=—_Six-eyed spiders, with long free labium, and
long maxillae provided with a well-developed scopula. The cephalothorax
is rather flat, and the abdomen is oval or cylindrical, the integument
being smooth and usually rather soft. The palpal organ of the male is of
simple structure._
The Dysderidae are divided into two sub-families, DYSDERINAE and
SEGESTRIINAE, for the most part confined to temperate regions.
(i.) The DYSDERINAE are easily recognised by a peculiarity of the
sternum. Instead of being merely excavated along its border for the
reception of the legs, its edge is folded round the coxae to meet the
carapace, and thus forms a series of collars or sockets in which the
limbs are articulated in perfect isolation from each other. These
spiders vary considerably in size, and are generally of a somewhat
uniform coloration, never marked with vivid patterns. There are eight
genera of this sub-family, two of which are represented in England.
_Dysdera cambridgii_ is not a rare spider under stones in rocky
localities, such as the Isle of Portland, and occurs, though less
commonly, all over the country in similar situations, and under the
loose bark of trees. It is half an inch in length, with a
chestnut-coloured cephalothorax and legs, and dull yellow abdomen. A
closely allied species, _D. crocota_, also occurs more rarely.
_Harpactes hombergii_ is common in vegetable débris and under decaying
bark. It is about a quarter of an inch in length, of slender form, with
black-brown cephalothorax and clay-coloured abdomen. The legs are
yellowish and annulated. More than forty exotic species of _Dysdera_ and
twenty-four of _Harpactes_ have been described. Another genus of the
Dysderinae is _Stalita_, which comprises three species, inhabiting the
caves of Dalmatia and Carniola.
(ii.) The SEGESTRIINAE include two genera, _Segestria_ and _Ariadna_.
_Segestria senoculata_ occurs in England in similar localities to those
where _Dysdera cambridgii_ is found. It is not much smaller than that
spider, and has a dark brown cephalothorax and legs and a dull yellow
abdomen, with a series of adder-like diamond-shaped black markings along
the middle. Two other species have occurred on rare occasions in
England, and twelve more are recorded from the various temperate regions
of the world.
_Ariadna_ is the only Dysderid genus which invades the tropical regions.
It includes about twenty species.
=Fam. 12. Caponiidae.=—This is a small family of three genera and about
twelve species, remarkable in having no pulmonary sacs but five tracheal
stigmata,[312] and in the peculiar arrangement of their six spinnerets,
those which are ordinarily median being in the same transverse line with
the anterior ones.
The single species of _Caponia_ (_C. natalensis_) inhabits South Africa,
while _Caponina_ has two species in South America. These spiders are
eight-eyed, but the two median posterior eyes are much the largest, and
these alone are present in the remarkable genus _Nops_, of which several
species inhabit South America and adjacent islands.
=Fam. 13. Prodidomidae.=—This small family includes about twenty species
of minute spiders from sub-tropical regions. They are eight-eyed, with
short smooth legs, terminated by two claws not dentated. The spinnerets
are especially characteristic.
_Prodidomus_ (_Miltia_) includes fifteen species from the Mediterranean
region, Africa, and America. _Zimris_ is an Asiatic genus. The single
species of _Eleleis_ (_E. crinita_) is from the Cape.
[Illustration:
FIG. 205.—Drassid Spiders. 1. _Drassus lapidosus._ 2. _Clubiona
corticalis._ 3. _Zora spinimana._ 4. _Micaria pulicaria._
]
=Fam. 14. Drassidae.=—_Elongate spiders with low cephalothorax. Legs
usually rather long, strong, and tapering, terminated by two pectinate
claws, armed with spines, and scopulate. The body is smooth or short
haired and frequently unicolorous and sombre-coloured, seldom ornate.
The eyes, normally eight, are in two transverse rows. The mouth-parts
(labium and maxillae) are long. Spinnerets as a rule terminal, and
visible from above._
This important family includes a large number of species from all parts
of the world, fifty-six being natives of the British Isles. There are
familiar examples in the brown or mouse-coloured spiders which scurry
away when stones are raised, or when loose bark is pulled off a tree.
The family may be divided into seven sub-families, of which four,
DRASSINAE, CLUBIONINAE, LIOCRANINAE, and MICARIINAE, are represented in
this country.
(i.) The DRASSINAE include more than twenty genera, some of which
possess numerous species and have a wide distribution. The following may
be mentioned:—
_Drassus_ contains twelve British species. The commonest is _D.
lapidosus_, a large dull brown spider, more than half an inch in length,
which lives beneath stones in all parts of the country. At least a
hundred species of this genus have been described.
_Melanophora_ (= _Prosthesima_)[313] includes a large number of species.
They are dark-coloured active spiders, many of them jet black and
glossy. Seven are recorded from the British Isles, the average size
being about a quarter of an inch. They are found under stones. A closely
allied genus is _Phaeocedus_, whose single species (_P. braccatus_) has
occurred, though very rarely, in the south of England. _Gnaphosa_ has
fifty-five species, of which twenty-eight are European, and four are
British.
(ii.) The CLUBIONINAE have the anterior spinnerets closer together, and
the eyes more extended across the caput than in the foregoing
sub-family. Nearly thirty genera have been established, of which three
claim special attention. _Clubiona_ includes more than 100 species,
chiefly inhabiting temperate regions. Fifteen are included in the
British list. They are mostly unicolorous, and yellow or brown in
colour, but a few (_C. corticalis_, _C. compta_, etc.) have a distinct
pattern on the abdomen. _Cheiracanthium_ is a large and widely spread
genus, counting three English species. There are more than a hundred
species of the genus _Anyphaena_, of which one only (_A. accentuata_)
occurs in this country, where it is common upon bushes and trees in the
south.
(iii.) The LIOCRANINAE include about twenty-four genera, of which
_Zora_, _Liocranum_, _Agroeca_, and _Micariosoma_ are sparingly
represented in this country.
(iv.) The MICARIINAE are a remarkable group of Spiders containing
numerous ant-like mimetic forms. Two species of _Micaria_ alone are
English, but that genus is abundantly represented on the Continent,
where the species mount up to forty. They are mostly small, dark,
shining spiders, which, though not particularly ant-like in form, recall
those insects both by their appearance and movements. Some of the exotic
genera, and particularly the South American genus _Myrmecium_, possess
remarkable instances of mimetic resemblance to ants. _Micaria pulicaria_
is a very pretty little spider, about a sixth of an inch in length,
black, with iridescent hairs, and some white marks on the abdomen. It
runs about in a very active ant-like fashion and does not object to the
sunshine. It is fairly abundant in England.
=Fam. 15. Palpimanidae.=—This family includes a few genera of exotic
spiders. They are especially characterised by the great development of
their anterior legs, which are not much used for locomotion, but are
frequently raised as the spider moves along, generally somewhat slowly,
by means of the other three pairs. The best known genera are _Metronax_
and _Stenochilus_ from India, _Huttonia_ from New Zealand, and
_Palpimanus_ from the Mediterranean region, Africa, and South Asia.
=Fam. 16. Eresidae.=—The Eresidae are a small family of cribellate
spiders whose systematic position has been the subject of much
discussion. In general appearance they resemble the Attidae (_vide
infra_), but this resemblance is quite superficial. On the whole they
seem more nearly allied to the following family than to any other. They
are stoutly built, with thick, strong legs, and live either in the
ground or on bushes, where they weave a close-textured web. One species,
_Eresus cinnaberinus_, has occurred on rare occasions in the south of
England, and the male, which is a third of an inch in length, is perhaps
the most striking member of our Spider fauna, the abdomen being scarlet,
with four (or sometimes six) black spots edged with white hairs. The
cephalothorax is black, with red on the postero-lateral borders. The
abdomen of the female is black.
=Fam. 17. Dictynidae.=—_Cribellate spiders, with oval cephalothorax and
broad convex caput, with the eyes, normally eight, ranged across it in
two straight or slightly curved transverse rows. Basal joints of
chelicerae long and strong, often bowed. Legs rather strong. Tarsi
three-clawed and devoid of scopula._
The Dictynidae are sedentary spiders which weave a web of irregular
strands, covered by the close weft which is the product of the
cribellum. Some live under stones or in holes in walls, while others
spin their webs in bushes or herbage. There are about sixteen genera, of
which _Dictyna_ and _Amaurobius_ are the most important.
Nearly a hundred species of _Dictyna_ have been described. They are
small spiders, usually living in grass and herbage. Thirty species
inhabit Europe and the neighbouring coast of Africa, and eight of these
are natives of Britain. _D. arundinacea_ is very abundant, especially in
heather. It is about an eighth of an inch in length. _D. uncinata_ is
also often met with. _Amaurobius_, of which about eighty species are
known, includes some species of much larger size. Three species are
native to this country, _A. ferox_, _A. similis_, and _A. fenestralis_.
_A. ferox_ is a large and rather formidable-looking spider, more than
half an inch in length, with powerful chelicerae. It is found under
stones and bark, and in cellars and outhouses. _A. similis_ is the
commonest species in England, though _A. fenestralis_ somewhat replaces
it in the north. They are smaller than _A. ferox_, but are found in
similar situations.
=Fam. 18. Psechridae.=—This is a small family of cribellate spiders,
consisting only of two genera, _Psechrus_ and _Fecenia_, and some eight
species, all natives of Southern Asia and the adjacent islands. The two
species of _Psechrus_ are large spiders. They make large domed webs,
which they stretch between trees or rocks, and beneath which they hang
in an inverted position.
The calamistrum of these spiders is short, about half the length of the
fourth metatarsus.
=Fam. 19. Zodariidae (Enyoidae).=—In this family are included a number
of remarkable exotic spiders, most of them somewhat Drassid-like in
appearance, but generally with three-clawed tarsi. The group appears to
be a somewhat heterogeneous one, the twenty genera of which it consists
presenting rather a wide range of characteristics.
_Cydrela_ is an African genus of moderate sized spiders, containing five
species of very curious habits. They scramble about and burrow in the
sand, in which, according to Simon,[314] they appear to swim, and their
chief burrowing implements are their pedipalpi, which are specially
modified, the tarsi in the female bristling with spines, and being armed
with one or more terminal claws.
_Laches_ (_Lachesis_) includes some larger pale-coloured spiders found
in Egypt and Syria, under stones in very hot and dry localities.
[Illustration:
FIG. 206.—_Hermippus loricatus_, ♂ × 2½. (After Simon.)
]
_Storena_ has representatives in all the tropical and sub-tropical parts
of the world, and numbers about fifty species. They are of moderate
size, with integuments smooth and glossy or finely shagreened, usually
dark-coloured, with white or yellow spots on the abdomen. _Hermippus_
(Fig. 206) is also African. _Zodarion_ (_Enyo_) includes about
thirty-five species of rather small, generally unicolorous spiders, very
active and fond of the sunshine. They spin no web, but have a retreat
under a stone. Their chief prey appear to be ants. Most of the species
are native to the Mediterranean region, the others belonging to Central
and Southern Asia.
Simon includes in this family the remarkable genus _Cryptothele_, found
in Ceylon, Malacca, New Guinea, and various Oceanic islands. They are
moderate sized brownish spiders, with hard integuments rugged with
tubercles and projections. Their most curious characteristic is their
power of retracting their spinnerets within a sort of sheath, so that
they become entirely invisible.
[Illustration:
FIG. 207.—_Hersilia caudata_, ♀. (After Pickard-Cambridge.)
]
=Fam. 20. Hersiliidae.=—This is a very distinct family of spiders, with
broad cephalothorax, with well-marked fovea and striae, and small, well
defined caput. The eyes, usually eight, are black except the median
anterior pair. The legs are long and thin, and the tarsi three-clawed.
The abdomen is oval or sub-globular, short haired, and generally of
greyish coloration. The spinnerets supply the chief characteristic, the
posterior pair being long—often excessively long—and two-jointed, the
terminal joint tapering and flexible. The colulus is large. They are
very active spiders, living on tree trunks or walls, or under stones,
but spreading no snare. Some of them are of considerable size.
_Hersilia_ includes nine species native to Africa and Asia. _Tama_ is
the only genus represented in the New World, two of its species being
found in South America, while others inhabit Africa, Asia, and
Australia. Another genus, _Hersiliola_, is principally African, but
extends into Spain.
=Fam. 21. Pholcidae.=—This is another very well-marked family. The most
striking peculiarity of its members is the possession of extremely long
and thin legs, the metatarsi being especially elongated, and the tarsi
furnished with several false articulations.
The eyes are also very characteristic. They are usually eight in number,
the two anterior median eyes being black, while the other six are white,
and arranged in lateral groups of three, sometimes on prominences or
stalks. The abdomen is sometimes nearly globular, but more often long
and cylindrical. Most of the genera, which, including several new genera
lately established by Simon, number more than twenty, are poor in
species, but enjoy a very wide distribution. This is explained by the
fact that many of them live in cellars and outhouses. This is the case
with the genus _Pholcus_, of which the sole English species _Ph.
phalangioides_ is a perfect nuisance in buildings in the most southern
parts of the country, “spinning large sheets of irregular webs in the
corners and angles, and adding to them year by year.”[315] Other genera
are _Artema_ (Africa, South Asia, Polynesia, America), which includes
the largest examples, and _Spermophora_, a six-eyed genus whose few
species are widely distributed.
=Fam. 22. Theridiidae.=—_Sedentary spiders, usually with feeble
chelicerae and relatively large abdomen. Snare irregular._
The Theridiidae, as here understood, are a very extensive family, and
more than half the British spiders (about 270 species) are included
within it. This family and the next present unusual difficulties of
treatment, and there is great divergence of opinion as to the most
satisfactory way of dealing with them. This is chiefly due to the fact
that, notwithstanding an infinite variation of facies, important points
of structure are wonderfully uniform throughout both the two groups,
while any differences that do occur are bridged over by intermediate
forms which merge into each other.
Simon[316] has become so impressed with the difficulty of drawing any
clear line between certain groups which he previously classed under the
Theridiidae and the spiders commonly known as Epeiridae, that he has
recently removed them from the Theridiidae and united them with the
orb-weaving spiders to form the Family Argiopidae, the family name
Epeiridae being discarded. The groups which, in his view, belong to the
Argiopidae will be indicated below. This view has not met with universal
acceptance, and notwithstanding the undoubted difficulty of clearly
distinguishing between the two families, it is more convenient in the
present work to maintain as a separate family a group of spiders nearly
all of whose members possess the easily recognised characteristic of
spinning a circular snare.
The Theridiidae and the Epeiridae form the great bulk of the sedentary
spiders. They do not wander in search of prey, but sit in snares of
various structure and wait for their victims to entangle themselves. The
spinnerets, organs whose peculiarities are often strongly marked in
other families, are here wonderfully constant in their arrangement and
general appearance, forming a compact rosette-like group beneath the
abdomen. Their eyes, normally eight in number, present an infinite
variety of arrangement. Their chelicerae and mouth-parts vary
considerably, but no abruptness of variation is distinguishable. This is
unsatisfactory from a systematic point of view, and the necessary result
is that certain groups might with equal propriety be classed with the
Theridiidae or the Epeiridae. The latter family will here be taken as
including all the orb-weaving spiders and a few groups which appear
inseparable from them.
We shall consider the Theridiidae as comprising the seven sub-families,
ARGYRODINAE, EPISININAE, THERIDIONINAE, PHORONCIDIINAE, ERIGONINAE,
FORMICINAE, and LINYPHIINAE, and shall briefly deal with them in this
order.
(i.) The ARGYRODINAE are very curious spiders with very long and often
flexible abdomen. They are commonly parasitic on the circular snares of
Epeirid spiders, between the rays of which they spin their own irregular
webs. There are three genera, _Argyrodes_, _Ariamnes_, and _Rhomphaea_,
which are distributed in the tropical and sub-tropical regions all over
the world.
(ii.) The EPISININAE hardly conform to the character of sedentary
spiders, being frequently found outside their webs. In most species the
abdomen is narrow in front and broader behind, where it is abruptly
truncated or bluntly pointed. The genus _Episinus_ is widely
distributed, and one species, _E. truncatus_, is one of our most
peculiar English spiders. It occurs occasionally under ledges of grassy
or heathery banks. The genus _Tomoxena_ is an inhabitant of tropical
Asia. _Janulus_ is found in the same regions, and in tropical America.
(iii.) The THERIDIONINAE are a large group of spiders, often very
ornate, and spinning snares of irregular threads running in all
directions. The abdomen is usually more or less globular. The chelicerae
are small and weak, and the paturon is transversely (not obliquely)
truncated for the reception of the small unguis or fang. The somewhat
long thin legs are almost or entirely destitute of spines.
We may consider certain genera as typical of the various groups into
which this sub-family naturally falls. _Theridion_ is the richest genus
of the entire order, numbering some 320 species, of which seventeen
inhabit the British Isles. During the summer months nearly every bush is
studded with the irregular webs of these little spiders, generally
prettily coloured, and with globular abdomen. The commonest is _T.
sisyphium_, which swarms on hollies and other bushes all over the
country. One of the handsomest is _T. formosum_, a rather local species,
about a sixth of an inch in length, with the abdomen beautifully marked
with oblique lines of white, yellow, red, and black. _T. tepidariorum_,
common in conservatories, is like a large and plainer edition of _T.
formosum_. _T. riparium_ is remarkable for the curious earth-encrusted
tube which it forms for the reception of its egg-cocoon. _T.
bimaculatum_ may often be seen among coarse herbage, holding on to its
ridiculously large egg-cocoon; it is a small spider, and the sexes are
more than usually unlike.
_Latrodectus_ and _Dipoena_ are associated exotic genera, including some
of the largest species of the group. _Latrodectus_ is peculiarly
interesting on account of the great reputation for especially poisonous
properties which some of its species have acquired. The New Zealand
“Katipo” is _L. scelio_, while _L. 13–guttatus_ enjoys an almost equally
evil reputation as the “malmignatte” in Corsica. The American species
_L. mactans_ (Fig. 197, p. 362) is also considered highly venomous.
These spiders form their irregular webs on low bushes, and it is curious
that they are usually marked with red or yellow spots on the abdomen.
They have been referred to in the section on the venom of spiders (see
p. 362).
The genus _Steatoda_ possesses one English species (_S. bipunctata_)
which is extremely common in buildings and in the angles of walls, and
is a rather striking spider, with dark cephalothorax, and livid brown
abdomen with a broken white stripe down the middle. Several closely
allied genera are also sparingly represented in this country, among
which may be mentioned _Crustulina_ (two species), _Asagena_ (one
species), _Teutana_ (two species), _Lithyphantes_ (one species),
_Laseola_ (five species), and _Euryopis_ (two species). In some of these
the male is provided with a stridulating organ between the thorax and
abdomen (Fig. 183, p. 327). The remarkable genus _Tetrablemma_ (see p.
318) is considered by Simon to have affinities with this group, though
Pickard-Cambridge, who first described it, is inclined to rank it among
the Dysderidae.
[Illustration:
FIG. 208.—_Trithena tricuspidata_ ♀. × 3½. (After Simon.)
]
(iv.) The PHORONCIDIINAE are a remarkable group of spiny Theridiids
whose superficial resemblance to the Gasteracanthinae of the Epeiridae
(see p. 409) has often deceived Arachnologists as to their true
affinities. There are eight genera, all exotic, inhabiting hot
countries, and spinning a _Theridion_-like web on bushes. _Phoroncidia_
has twelve species in South Asia and Madagascar. _Trithena_ (Fig. 208)
is its American representative, five species being found in South
America. _Ulesanis_ has about twenty species, and extends from South
America to Australia.
(v.) The ERIGONINAE are an immense group of minute, sober-coloured
spiders, which include the “Money-spinners” of popular nomenclature, and
are largely responsible for the gossamer which fills the air and covers
every tuft of grass in the autumn. The number of species described is
very large and constantly increasing, and more than a hundred are
recognised as British.
Desperate efforts have been made of late years to grapple with this
almost unmanageable group, but the multitude of genera which have been
proposed can hardly as yet be considered to be finally established. The
small size of these spiders, which renders the aid of a microscope
necessary to make out their structural peculiarities, robs them of their
attractiveness to any but the ardent Arachnologist, but they number
among them some of our most remarkable English forms, and many of them
well repay examination. The smallest English species, _Panamomops
diceros_, measures about 1 mm. (about ¹⁄₂₅ inch) in length. Many of the
groups are jet black, some with dull and others with shiny integuments.
They are never greatly variegated in hue, but the glossy black of the
cephalothorax, combined with red-brown or yellow legs, gives to some
species a rather rich coloration.
[Illustration:
FIG. 209.—Profile of cephalothorax of 1, _Lophocarenum insanum_; 2,
_Dactylopisthes digiticeps_; 3, _Walckenaera acuminata_ (+ abdomen);
4, _Diplocephalus bicephalus_; 5, _Metopobractus rayi_.
]
It is impossible here to deal with this sub-family in detail. Some of
its members must be familiar enough to everybody, and the reader is
recommended to spend an hour of a warm autumn day in watching them
depart on the ballooning excursions, of which a description has been
given (see p. 341), from the knobs which surmount iron railings in a
sunny spot. Among them he is pretty sure to find the genus _Erigone_—
containing some of the largest members of the group—strongly
represented.
In some species the male presents a remarkable difference from the
female in the structure of its cephalothorax, which has the head region
produced into eminences sometimes of the oddest conformation. An extreme
example is seen in _Walckenaera acuminata_, a fine species in which the
male caput is produced into a sort of spire, bearing the eyes, and
nearly as high as the cephalothorax is long (Fig. 209, 3).
(vi.) The FORMICINAE include only two genera, _Formicina_ (South Europe)
and _Solenysa_ (Japan). They are somewhat ant-like in appearance.
(vii.) The LINYPHIINAE are closely allied to the Erigoninae, but the
legs are usually armed with spines, and very commonly the female has a
dentated claw at the end of the pedipalp.
We include here about thirty genera of spiders of moderate or small
size, living for the most part on bushes or herbage. The characteristic
Linyphian web is a horizontal sheet of irregular strands, anchored to
neighbouring twigs or leaves by cross threads in all directions, and the
spider generally lurks beneath the web in an inverted position. Some of
the larger species are very familiar objects, _Linyphia triangularis_
being one of the most abundant English spiders, filling furze and other
bushes with its extensive spinning work.
The sub-family may be roughly divided into three groups, of which the
first is small, consisting of only three exotic genera of one species
each. _Donachochara_ may be taken as the type genus. They are
moderate-sized spiders with rather short legs, found in France and
Holland.
The second group consists of a number of genera of small spiders,
sober-coloured, and generally more or less unicolorous in brown, yellow,
or black, living in herbage. The sexes are much alike, the males never
exhibiting the excrescences on the caput so often met with in the
Erigoninae. The genus _Tmeticus_ may be considered the type. It includes
about forty species, of which about half are British. They are mostly
dull yellow or brown spiders, averaging perhaps the eighth of an inch in
length. Allied genera which are represented in England are _Porhomma_
(twelve species), _Microneta_ (twelve species), _Sintula_ (twelve
species). The American cave-genus _Anthrobia_ comes here.
The third and last group is that including _Linyphia_ and allied genera.
They are moderate-sized or small spiders with long spiny legs and
particularly long tarsi. The abdomen is generally decorated. The caput
is frequently rather prominent and crowned with hairs.
Of the large number of spiders which have been described under the
generic name of _Linyphia_, Simon[317] only admits about fifty species.
Ten are included in the British list. _L. triangularis_ has already been
mentioned, but there are other common species, as _L. montana_, _L.
marginata_, and _L. clathrata_. The members of most of the associated
genera are rather small in size. We may briefly mention _Bolyphantes_,
_Bathyphantes_, _Lephthyphantes_, and _Labulla_, all of which include
English species.[318]
=Fam. 23. Epeiridae.=—This family includes all the spiders which spin
circular or wheel-like snares, the highest form of spider industry,
together with a few forms so closely allied in structure to orb-weaving
species as to be systematically inseparable from them. It is practically
co-extensive with the Argiopinae, Tetragnathinae, and Nephilinae of
Simon’s Argiopidae in the _Histoire naturelle des araignées_.[319]
No one is unfamiliar with the orbicular snares, the structure of which
has already been described with some minuteness (see p. 344), and some
of the spiders which construct them are among the best known members of
the order.
It is impossible here to deal with the multitudinous forms embraced by
this family. We must mention those genera richest in species, and some
others of special interest. It will be convenient to indicate eight
sub-families or groups, which include most of the forms likely to be met
with. These are the THERIDIOSOMATINAE, TETRAGNATHINAE, ARGIOPINAE,
NEPHILINAE, EPEIRINAE, GASTERACANTHINAE, POLTYINAE, and ARCYINAE.
(i.) The THERIDIOSOMATINAE are a small group which might with equal
propriety be classed with the Theridiidae or the Epeiridae.
_Theridiosoma argenteolum_ is a rare spider in Dorsetshire. It is a
minute spider, one-twelfth of an inch in length, with silvery white
globular abdomen variegated with reddish brown, and yellow cephalothorax
with darker caput. Some allied spiders spin a roughly circular snare.
(ii.) The TETRAGNATHINAE consist chiefly of two genera, _Pachygnatha_
and _Tetragnatha_. The first consists of spiders which are not
orb-weavers, but live in herbage, especially in swampy places. Two
species, _Pachygnatha clerckii_ and _P. degeerii_, are common in
England, and a third, _P. listeri_, is sometimes met with. They are
rather striking, prettily marked spiders, with strongly developed
chelicerae.
The species of _Tetragnatha_ are true orb-weavers, and may easily be
recognised by their cylindrical bodies, elongated chelicerae, and long
legs, stretched fore and aft along the rays of their webs. Five species
have been recorded from England, and the genus contains at least a
hundred species in all; almost every country in the world, regardless of
its latitude, supplying examples.
Simon associates with these spiders the genus _Meta_, which includes
perhaps our commonest Epeirid, _Meta segmentata_, a smallish and not
very striking Orb-weaver, with a rather elongated or subcylindrical
abdomen. Every garden is pretty sure to abound in it.
(iii.) The ARGIOPINAE include many large and very striking members of
the Epeiridae. There are about a hundred species of _Argiope_ (Fig. 198,
p. 379) spread over the tropical and sub-tropical countries of the
world. They rarely invade the temperate regions, but _A. bruennichi_ is
found in South Europe, and _A. trifasciata_ in Canada. The large spiders
with transverse bars of yellow or orange on their abdomen, and often
with a silvery sheen, belong to this genus. The species of the allied
genus _Gea_ are generally much smaller, and their abdomen more
elongated. Both genera are found in tropical and sub-tropical regions
all over the world. _Argiope_ always sits in the middle of its circular
web. There are invariably some flossy zigzag bands of silk stretched
between two of the rays, and the web is generally accompanied by an
irregular net on its border, where the much smaller male may be found.
(iv.) Among the NEPHILINAE are to be found the largest Epeirids. Indeed,
the largest yield in size only to the Aviculariidae. _Nephila_ is a
tropical genus, numbering about sixty species. The abdomen is generally
elongated and somewhat cylindrical, and is strikingly variegated. It is
in this group that the disparity in size between the sexes is most
marked (see p. 379).
(v.) The EPEIRINAE[320] include the bulk of the Orb-weavers, and form a
very extensive group. Five genera and twenty-eight species are in the
British list.
No spider is more familiar than _Epeira diademata_ (Fig. 181, p. 325),
_the_ Garden-spider, _par excellence_, which attains its greatest size
and spreads its largest snares in the autumn. The smaller and much less
conspicuous _Zilla x-notata_ is sure to be found abundantly in the same
locality. Several other Epeirids are to be found in this country,
especially in the south, by sweeping heather or bushes with a net, or
shaking the boughs of trees over an umbrella or other receptacle. The
little apple-green species is _Epeira cucurbitina_. _E. cornuta_ is
extremely common in marshy places all over the country. In furze bushes,
and often among sedge in swampy places, will frequently be found _E.
quadrata_, one of the largest and handsomest species we possess. The
ground-colour may vary from orange-red to green, and there are four
conspicuous white spots on the abdomen. The tent-like retreat which this
spider makes near its snare often catches the eye.
[Illustration:
FIG. 210.—_Epeira angulata_, ♀.
]
_E. umbratica_ is a dark flat, somewhat toad-like Epeirid of retiring
habits, which stretches its snare usually on wooden palings, between the
timbers of which it squeezes its flat body, and waits for insects to
entangle themselves.
Two of our finest Epeiras, _E. pyramidata_ and _E. angulata_ (Fig. 210),
are seldom met with, and only in the south.
Our only _Cyclosa_ (_C. conica_) is easily recognised by the peculiar
form of its abdomen, which is greatly prolonged beyond the spinnerets.
It is a small, rather dark species, which constructs a particularly
perfect snare.
Five British Epeirids belong to the genus _Singa_. They are small
creatures, not exceeding a sixth of an inch in length. They live in
heathery and marshy localities.
(vi.) The GASTERACANTHINAE are a remarkable group of Epeirids,
characterised by the hard and coriaceous integument covering the
abdomen, which is usually furnished with a number of more or less
formidable thorn-like spines, calculated to render these spiders by no
means pleasant eating for insectivorous birds. An even more constant
characteristic is the presence on the back of the abdomen of a number of
“sigilla,” or somewhat seal-like impressions arranged symmetrically,
four forming a trapezium in the middle, while the others are distributed
round the border.
[Illustration:
FIG. 211.—_Gasteracantha minax_, ♀.
]
There are about 200 species of _Gasteracantha_, all natives of tropical
countries.
The spiders of the genus _Micrathena_ (_Acrosoma_) have a more elongate
cephalothorax, and sometimes the spines are exceedingly long, far
exceeding the length of the body proper. Among the less spiny members of
this group are some remarkable mimetic ant-like forms.
(vii.) The POLTYINAE include some remarkable spiders, found in Africa
and South Asia for the most part, though sparingly represented in
America and Oceania. They are generally largish spiders, often with a
very odd conformation of the abdomen, which is generally much raised.
The type genus is _Poltys_.
(viii.) The ARCYINAE, which are more characteristic of Australia and the
neighbouring islands, are a small group of spiders, usually yellow with
black markings, and with the somewhat square-shaped cephalothorax
usually prominent at the angles. The type genus is _Arcys_.
=Fam. 24. Uloboridae.=—The Uloboridae are cribellate spiders, with
rather elongate cephalothorax, devoid of median fovea. The cribellum is
transverse and generally undivided. The first pair of legs are usually
much the longest. The metatarsi of the fourth legs, in addition to the
calamistrum, bear a number of generally regularly arranged spines. The
eyes are often situated on tubercles. Three sub-families are recognised,
DINOPINAE, ULOBORINAE, and MIAGRAMMOPINAE.
(i.) The DINOPINAE are a small group comprising only two genera,
_Dinopis_ and _Menneus_. The calamistrum is short, occupying not more
than half of the metatarsus. Twenty species of _Dinopis_ and six of
_Menneus_ are scattered over the tropical regions of the world.
(ii.) The ULOBORINAE include a number of spiders which have been
described under several generic names, but are now considered to fall
into two genera, _Sybota_ and _Uloborus_. _Sybota_ has only two species,
one in the Mediterranean region and one in Chili. There are about sixty
species of _Uloborus_, some of which have a wide distribution, while
many (_e.g._ _U. republicanus_, of Venezuela) are social. The type
species, _U. walckenaerius_, is a very rare spider in England.
(iii.) The MIAGRAMMOPINAE include two genera containing some very
interesting forms. The genus _Miagrammopes_, of which twenty species
have been described, though the number is probably far greater, is
characterised by a very long cylindrical abdomen, and by the apparent
possession of only four eyes, in a transverse row. These are really the
posterior eyes; and the anterior eyes, or some of them, are present in a
very reduced condition. Little is known of the habits of these spiders.
[Illustration:
FIG. 212.—_Hyptiotes paradoxus_, ♀.
]
The other genus, _Hyptiotes_, though only boasting three species,
possesses a special interest on account of the remarkable snare
constructed by the spiders which belong to it. This has already been
described in the section upon defective orb-webs (see p. 349).
The type species, _H. paradoxus_, is very rare in England, and though
small and inconspicuous, it is certainly one of the most curious members
of our Spider fauna.
=Fam. 25. Archeidae.=—This small family includes certain remarkable
fossil spiders from Baltic amber, and two rare recent forms, _Archea_
(_Eriauchenus_) _workmani_ from Madagascar, and _Mecysmauchenius
segmentatus_ from America. The chelicerae, which are extraordinarily
long, are articulated far away from the mouth-parts. The caput is
clearly marked off from the thorax, and is much raised. In several other
respects these spiders are very distinct from all other members of the
order.
=Fam. 26. Mimetidae.=—The Mimetidae form a small group in general
appearance recalling the Theridiidae, with which family they were for a
long time incorporated. The chief genera are _Ero_, _Mimetus_, and
_Gelanor_. _Ero furcata_ (= _thoracica_) is a pretty little spider, not
rare among grass in England. The upper side of its very convex abdomen
is marked with red, yellow, and black, and bears two little
protuberances or humps near the middle. It is only about an eighth of an
inch long. Its interesting egg-cocoon has already been alluded to (see
p. 358). _E. tuberculata_ has been found on rare occasions in this
country. There are about ten other species of _Ero_, all small spiders,
and living in temperate regions. The genus _Mimetus_ (in which is merged
Blackwall’s _Ctenophora_) includes a number of larger, more
strongly-built spiders, living for the most part in tropical countries.
The genus _Gelanor_ (_Galena_) is the American representative of the
group, its three species being rather large spiders, inhabiting Central
and South America. The males of this genus have remarkably long and
slender pedipalpi, much longer than the whole body.
=Fam. 27. Thomisidae.=—The Thomisidae are the Latigrade spiders of
Latreille, and the “Crab-spiders” of popular nomenclature. Their legs
are extended more or less laterally instead of in the normal fore and
aft directions, and their progression is frequently strikingly
crab-like. They form a very large group of more than 140 genera,
including spiders of every size, and they are to be found in every
quarter of the world. Forty-three species are British. Many strange
forms are included in this group, and several of the sub-families into
which it has been divided contain only one or two genera. The bulk of
its members fall into the sub-families THOMISINAE, PHILODROMINAE, and
SPARASSINAE.
(i.) The THOMISINAE (MISUMENINAE of Simon’s _Hist. Nat._) include what
may be called the more normal members of the family, distributed among
more than sixty genera. Six of these genera are represented in the
British Isles. Our commonest Crab-spider is probably _Xysticus
cristatus_, abundant everywhere in grass and herbage. Young specimens
may often be seen upon iron railings in the autumn. Twelve other species
of that genus are on the British list. They are of small or moderate
size, rarely exceeding a quarter of an inch in length. A closely allied
genus is _Oxyptila_, of which we have seven species. The more striking
members of this sub-family to be found in England are our single
representatives of the genera _Misumena_, _Diaea_, and _Thomisus_.
_Misumena vatia_ is a handsome species, the female measuring sometimes
more than a third of an inch, and having its large yellow or green
abdomen marked, in many specimens, with a pair of bright red bands,
which, however, are not always present. The males are much smaller and
darker. It is common in some parts of England, especially in the south,
where it is to be sought for in bushes and trees.
[Illustration:
FIG. 213.—Thomisid spiders. =A=, _Micrommata virescens_, ♀; =B=,
_Xysticus pini_, ♀; =C=, _Philodromus margaritatus_, ♂; =D=,
_Tibellus oblongus_, ♀.
]
_Diaea dorsata_ is one of our prettiest British species, with light
green legs and cephalothorax, and a yellow abdomen with a red-brown
central marking. It is common in the New Forest and other southern
localities. The female attains a quarter of an inch in length.
_Thomisus onustus_, a rare spider among heather, is recognisable by the
shape of its abdomen, which is broadest behind and abruptly truncated.
When adult the abdomen is a pale yellow, but the young are suffused with
a pink hue closely corresponding with that of the heather blossom in
which they are frequently found sitting.
(ii.) The PHILODROMINAE have the cephalothorax more rounded in front,
and the legs, especially the second pair, usually longer than in the
Thomisinae. There are ten genera, of which the most important is
_Philodromus_, which numbers about a hundred species. They are active
spiders, living upon bushes and trees, and most of them are inhabitants
of temperate regions. We have about twelve species in the British Isles.
The commonest is _Ph. aureolus_, which is abundant on bushes in most
parts of the country. Some species are very prettily marked, and one,
_Ph. margaritatus_ (Fig. 213, C) presents a very good example of
protective coloration, being almost indistinguishable on the blue-grey
lichen on tree trunks, where it lies in wait for insects.
Another important genus, including some fifty species, is _Thanatus_,
extending from tropical to arctic regions, but very sparingly
represented in England. _Th. striatus_ (= _hirsutus_) occurs
occasionally, and one example of the fine species _Th. formicinus_ has
been taken in the New Forest. The members of this genus as a rule affect
dry and sandy habitats.
The genus _Tibellus_ includes few species, but has a wide distribution.
The type species _T. oblongus_ (Fig. 213, D) is found in the temperate
regions all over the world, and is common in England. It is a pale
straw-coloured spider with a much elongated abdomen. It closely
resembles the stems of dry grass in hue, and when alarmed it remains
perfectly still with its legs embracing the stem and its abdomen closely
applied to it.
(iii.) The SPARASSINAE[321] include most of the large Latigrade forms,
and number about forty genera.
_Heteropoda venatoria_ is a cosmopolitan species, and though proper to
warm countries, is often introduced here on hothouse plants, and has
been known to establish itself in the open air in botanical gardens. Our
only indigenous member of this sub-family is _Micrommata virescens_
(Fig. 213, A). This striking spider is found, though rarely, in the
south of England. The female is half an inch in length and of a vivid
green hue, while the more cylindrical abdomen of the male is yellow with
three longitudinal scarlet lines. Other genera are _Sparassus_,
_Torania_, and _Delena_.
(iv.) The APHANTOCHILINAE include two curious genera which are
exclusively American. The labium is much reduced and the sternum is
shortened, terminating between the third pair of legs. The species of
_Aphantochilus_ are largish, glossy-black spiders, sometimes spotted
with white. Some of them mimic ants of the genus _Cryptocerus_. The
other genus is _Bucranium_.
(v.) The STEPHANOPSINAE include about sixteen genera, of which the best
known are _Stephanopsis_ and _Regillus_. There are about fifty species
of _Stephanopsis_, most of them Australian, while the eight species of
_Regillus_ belong to Africa and South Asia.
The mimetic form _Phrynarachne decipiens_ has already been alluded to
(see p. 374).
(vi.) The SELENOPINAE consist of a single genus, _Selenops_, of which
ten or twelve species are known, some of which are very widely
distributed, though confined to hot regions. These spiders, which are
all large, are easily recognised by their extremely flat bodies and the
peculiar arrangement of their eyes, all eight of them being placed more
or less in a single transverse line.
=Fam. 28. Zoropsidae.=—The Zoropsidae are cribellate spiders of large
size, with well-developed scopulae on tarsi and metatarsi. The cribellum
is divided, and the calamistrum, which is very short, is not well
developed. Most are inhabitants of hot regions, where they live under
stones or bark. _Zoropsis_ has six species, chiefly inhabitants of North
Africa, though representatives occur on the European side of the
Mediterranean. _Acanthoctenus_ has two species in South and Central
America.
=Fam. 29. Platoridae.=—The Platoridae are Thomisid-like, medium-sized
spiders, generally with a uniform yellow or brown coloration. The
spinnerets are their most characteristic features. The median pair
present a large flat surface studded with two parallel rows of large
fusulae, while the anterior pair are situated outside them, and are thus
widely separated. There are only three genera, and very few species of
this family. _Plator insolens_ is a Chinese species. _Doliomalus_ and
_Vectius_ belong to South America.
=Fam. 30. Agelenidae.=—_Sedentary spiders with slight sexual dimorphism;
with three tarsal claws and devoid of scopulae._
The Agelenidae spin a more or less extensive web of fine texture,
usually accompanied by a tubular retreat. Our commonest cellar spiders
belong to this group, which may be divided into three sub-families,
CYBAEINAE, AGELENINAE, and HAHNIINAE.
(i.) The CYBAEINAE include some sixteen genera, of which two deserve
special mention on account of the peculiar habits of the spiders
belonging to them.
_Desis_ is a genus of marine spiders, said to live on coral reefs below
high-water mark, and to remain in holes in the rock during high tide,
enclosed in cocoons impermeable to the sea-water. At low tide it is
stated that they come forth and prey upon small crustaceans.
_Argyroneta_ has only one species, _A. aquatica_, spread throughout
Europe and North and Central Asia. It is the well-known “Water-spider,”
which is so often an object of interest in aquaria.
(ii.) The AGELENINAE also contain sixteen genera, but it is a much
larger group, some of the genera being rich in species. They are mostly
moderate or large-sized hairy spiders, living in temperate or cold
climates. There are about fifty species of _Tegenaria_, seven of which
have been recorded as British.
Our commonest Cellar-spider is _T. derhamii_, but the very large
long-legged species found in houses in the southern counties of England
is _T. parietina_ (= _guyonii_ = _domestica_). There are not many
species of _Agelena_, but one, _A. labyrinthica_, is a common object in
this country, with its large, close-textured web and accompanying tube
spread on grassy banks by the wayside. _Coelotes atropos_ is a
formidable-looking spider, found occasionally under stones in England
and Wales. Another genus, _Cryphoeca_, has three British
representatives.
(iii.) The HAHNIINAE are recognised at once by their spinnerets, which
are arranged in a single transverse line, the posterior pair being on
the outside, and generally much the longest. _Hahnia_ contains several
species of very small spiders, of which four or five are British,
usually occurring among moss or herbage. The aberrant form _Nicodamus_
(_Centropelma_), usually placed among the Theridiidae, is removed by
Simon to the Agelenidae, forming by itself the sub-family (iv.)
NICODAMINAE.
=Fam. 31. Pisauridae.=—The Pisauridae are hairy, long-legged spiders,
intermediate, both in structure and in habits, between the Agelenidae
and the Lycosidae. Many new genera have recently been added to the
group, but many of them only include one or two species.
_Pisaura_ is spread throughout the temperate regions of the Old World,
and _P._ (_Ocyale_) _mirabilis_ is common in England, being found
abundantly in woods and on commons. It is a striking spider, more than
half an inch in length, and its elongate abdomen is marked on either
side with a sinuous longitudinal white band.
There are some thirty species of _Dolomedes_ scattered over the
temperate regions of the world. _D. fimbriatus_ is a rare species in
marshy spots in the south of England, and is one of the largest British
spiders. The ground-colour is deep brown, with two longitudinal
yellowish stripes both on cephalothorax and abdomen.
The genus _Dolomedes_ is replaced by _Thaumasia_ in South America.
=Fam. 32. Lycosidae.=—These are what are popularly known as
“Wolf-spiders.” They are vagabond hunting spiders, spinning no snare,
but chasing their prey along the ground, and in the breeding season
carrying their egg-bags with them, attached beneath the abdomen. Some of
them burrow in the loose earth or sand, but others seem to have nothing
in the way of a habitation.
[Illustration:
FIG. 214.—Lycosid Spiders. =1=, _Lycosa fabrilis_, ♀; =2=, _Lycosa
picta_, ♀; =3=, _Pardosa amentata_, ♀.
]
The arrangement of the eyes is very characteristic. They are in three
rows. The front row consists of four small eyes above the insertion of
the chelicerae, and directed forwards. Two comparatively very large eyes
form the next row, and occupy the upper angles of the facies, being also
directed forwards. The third row consists of two medium-sized eyes
placed dorso-laterally on the caput, some distance behind the rest, and
looking upwards. The tarsi are three-clawed. The so-called “Tarantula”
spiders belong to this group, though the name has been so abused in
popular usage, and has passed through so many vicissitudes in scientific
nomenclature, that it is difficult to tell what creature is intended by
it. In America the Aviculariidae are commonly called Tarantulas.
The two chief genera of this extensive family are _Lycosa_ and
_Pardosa_.
The genus _Lycosa_ includes about 400 species. It has been broken up
from time to time into various genera (_Trochosa_, _Pirata_,
_Tarentula_, etc.), but these glide into each other by imperceptible
degrees, and are now discarded. They are large or moderate-sized
spiders, found in every part of the world. About twenty species are
British, some of them being fine and handsomely marked. One of the
prettiest is _Lycosa picta_, common on the sandhills in some localities.
Some exotic species are very large, _Lycosa ingens_, from Madeira,
measuring sometimes more than an inch and a half in length.
_Pardosa_ (Fig. 188, p. 341) is not so rich in species, but the
individuals of some species are wonderfully numerous. Hundreds of _P.
lugubris_, for example, may be seen scampering over the dead leaves of a
wood in the autumn. These spiders are generally sombrely coloured and
well covered with hair. Perhaps the commonest and most widely spread
species in this country is _P. amentata_.
=Fam. 33. Ctenidae.=—The Ctenidae are _Lycosa_-like spiders, having in
certain points of structure close affinities with the Pisauridae and the
Sparassinae of the Thomisidae. The limits of the family are not well
defined, and many arachnologists place in it some of the genera allotted
above to the Pisauridae, while others do not consider the group
sufficiently marked off to constitute a separate family at all. As here
understood they are equivalent to the Cteninae of the Clubionidae in
Simon’s _Histoire naturelle_. The eyes are arranged in the _Lycosa_
fashion, but the tarsi have only two terminal claws and well-developed
“claw-tufts,” frequently accompanied by a scopula. There are strong,
regularly-arranged spines under the tibiae and tarsi.
There are about fifteen genera. _Uliodon_ numbers six species of large
hairy spiders in Australia. _Ctenus_ is rich in species, having about
sixty, found in all hot countries, but especially in America and Africa.
They are also of large size and usually of yellowish coloration, often
diversified by a pattern on the abdomen. The fifteen species of
_Leptoctenus_ are proper to tropical Asia. Acantheis from South Asia and
_Enoplectenus_ from Brazil are more slender, elongate forms, recalling
_Tetragnatha_. _Caloctenus_ includes a number of _Pardosa_-like spiders
found at a high elevation in South America.
The Ctenidae have the habits of the Lycosidae, and are wandering
spiders, some forming a burrow in the ground.
=Fam. 34. Senoculidae.=—The South American genus _Senoculus_
(_Labdacus_) alone constitutes this family. The species are probably
numerous, but ten only have been described. They are moderate-sized
spiders, spinning no web, but running with astonishing speed over the
leaves and stems of plants. The generic name is really inapplicable, as
there are eight eyes, but the anterior laterals are much reduced. The
abdomen is long, and the legs are long and unequal, the first pair much
the longest and the third much the shortest.
=Fam. 35. Oxyopidae.=—The Oxyopidae form a well-marked group, with oval
cephalothorax somewhat narrowed in front, and lanceolate abdomen. The
eight black eyes have a characteristic arrangement, and the anterior
medians are always very small. The legs are long and tapering, and not
very unequal, and are furnished with particularly long spines, which
give these spiders a very characteristic appearance. There are eight
genera, of which the most important are _Pucetia_ and _Oxyopes_.
_Pucetia_ contains a number of rather large spiders, generally bright
green, often variegated with red. They affect particular plants. For
instance, _P. viridis_, which occurs in Spain, is always found on
_Ononis hispanica_. There are about thirty species of this genus
distributed over the tropical and sub-tropical regions of the world.
_Oxyopes_ numbers many species, certainly more than fifty, and has a
similar distribution, but some of its members invade colder regions.
They are of rather small size. _O. lineatus_ is a very rare spider in
the south of England.
The Oxyopidae are diurnal spiders, running over plants in search of
prey, and often leaping, after the fashion of members of the following
family.
=Fam. 36. Attidae (Salticidae).=—_Wandering spiders with cephalothorax
broad anteriorly, and bearing eight homogeneous eyes in three rows. Four
eyes, largely developed, are directed forward; the remaining four eyes
are placed dorsally in two rows, the first pair being much reduced in
size._
The Attidae or Jumping-spiders form the most extensive family of the
whole order, the known species amounting to something like four
thousand. It is only of late years that their vast numbers have begun to
be realised, for their vagabond habits and great activity enabled them
to a great extent to elude the earlier collectors, whose methods were
not as thorough as those now in vogue. Their real home is in the
tropical regions, temperate fauna being comparatively poor in Attid
species. France boasts nearly 150, but only 37 are recorded for the
British Isles, and 2 at least of these are recent introductions.
Some of the tropical forms are most brilliantly coloured, glowing with
vivid colours and metallic hues, and they have frequently excited the
admiration of travellers. The coloration is nearly always due to the
hairs and scales with which the spiders are clothed, and is,
unfortunately, almost incapable of preservation in the collector’s
cabinet.
These spiders are all wanderers, spinning no snares, though they form a
sort of silken cell or retreat, in which the female lays her eggs. Their
habits are diurnal, and they delight in sunshine. They stalk their prey
and leap upon it with wonderful accuracy. They invariably attach a
thread at intervals in their course, and on the rare occasions when they
miss their aim while hunting on a perpendicular surface, they are saved
from a fall by the silken line proceeding from the spot whence the leap
was made.
[Illustration:
FIG. 215.—Attid Spiders. =A=, _Salticus scenicus_, ♂; =B=, _Marpissa
muscosa_, ♀; =C=, _Synemosyna formica_, ♀; =D=, _Ballus variegatus_,
♀.
]
The movements of these spiders are sufficient to indicate their
systematic position without entering upon structural details, but their
eyes deserve a special mention. They are all dark-coloured and very
unequal in size, and they occupy the whole area of the caput, usually
forming a large quadrilateral figure. Four large eyes occupy the facies
or “forehead,” the medians being especially large. Next come two very
small eyes, behind the anterior laterals, and lastly two of medium size
at the posterior corners of the caput.
This vast family does not lend itself easily to division into
sub-families, and it will be impossible here to do more than indicate a
very few of the multitudinous forms.
The most familiar British example is _Salticus scenicus_ (_Epiblemum
scenicum_), the little black and white striped spider to be seen hunting
on walls and fences during the summer. _Marpissa muscosa_ is the largest
English species, measuring about half an inch. It has a brownish-yellow
coloration, and is found, though not commonly, in similar situations.
_Attus pubescens_ affects grey stone walls, on which it is nearly
invisible except when moving. The other British species are mostly to be
found on trees and shrubs or among herbage, or hunting over bare sandy
spots in the sunshine. A few (_Marpissa pomatia_, _Hyctia nivoyi_) are
fen species. _Hasarius falcatus_ is a handsome spider, common in woods
in some localities.
The species differ much in their jumping powers; the Marpissas, for
example, are not great leapers, but the little _Attus saltator_, found
on sandhills, jumps like a flea, and the North American species _Saitis
pulex_ has a suggestive specific name.
Again, in this family there are mimetic forms resembling ants.
_Myrmarachne formicaria_ (_Salticus formicarius_) is found very rarely
in England, but is not uncommon on the Continent.
_Synageles_ and _Synemosyna_ are allied genera. _Phidippus_ is a genus
well represented in America, and _Ph. morsitans_ has already been
mentioned (p. 365) in connexion with its poisonous reputation. _Astia_
and _Icius_ have American representatives (see pp. 381, 382), though the
type species belongs to the Old World.