Chapter XV (1)

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._

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.

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._

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.

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.

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.

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.

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.

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.

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.

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.

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.