634 



Sl'IDKKS 



SPIELBERG 



crab-like form, and resembles in colour and general 

 appearance the fruit of Hymeiura verrucosa, a tree 

 common in the forests where this spider is found ; 

 Drapetitea sociali* is verj- like tin- bark of birchea 

 and other trees on which it lives ; among the 

 Lycosidje there are scores 

 of dull-coloured species 

 that live on the ground ; 

 Dr McCook describes one 

 form which has a tint 

 like that of the water 

 upon which it is con- 

 stantly found ; about a 

 dozen species which live 

 on leaves are recorded as 

 protectively green; 

 many Thomisidse are 

 coloured like the (lowers 

 on which they await 

 Fig. 5. their victims ; Ornitho- 



ffatteracantha rufotpinota, scatoides decipiens, first 

 female, mag. 2J diameters, described by Forbes, is, 

 (After E. 0. Peckham.) as ite name suggests, 

 most deceptively like 



bird-excrement, HO that the discoverer actually 

 plucked the leaf on which the spider was resting, 

 And looked at it for some moments before he dis- 

 cerned his captive. In short, what Mr Wallace 

 said about the leaf-like butterfly is often true of 

 spiders : ' Size, colour, form, markings, and habits 

 all combine to produce a disguise which may be 

 said to be absolutely perfect.' 



Again, there are spiders which are rendered 

 inedible by an armature of spines and plates, and 

 many of these (e.g. some Gasteracanthid;e ) are 

 very brilliantly coloured. It is possible that their 

 conspiciiousness impresses their enemies with the 

 f.fi that they are better left alone. 



1,,-istly, there are spiders which exhibit a pro- 

 tective mimicry of animal forms. ' Spiders most 

 commonly mimic ants,' Mrs Peckham says ; 'hut 

 we hear also of their imitating beetles, snail-shells, 

 ichneumon and horse flies. There is also a curious 

 Madagascar species which looks exactly like a 

 little scorpion, the resemblance being heightened 

 by the habit of curving it- flexible tail up over its 

 back when irritated. Nearly all the species of 

 < 'oecorhestes and Hornalattns resemble Iveetles ; 

 Cytaraclme is like a snail-shell : Si/>ni</i'/rs /ic-iitu 

 and Syneinotynn formica are good examples of those 

 which have a mimetic likeness to ants. 



Clastification. Spiders of tin- Bird-catcher ( My- 

 gale) type differ from all the others in having four 

 pulmonary sacs (Tetrapneumnne.*). The Dipneu- 

 menu's, which form the vast nuijoriiy, including 

 several thousand species, are conveniently classified 



in riling to their habiu whether sedentary or 



wanderers, and according to their spinning-work, 

 tliU physiological classification being also justified 

 anatomically. Another fact of some importance 

 SM the presence or absence of a cribellum. Thus 

 we distinguish 



Sub-order TrrRAPXEimoifK 

 Tribe I. Territrlaritt : Tunnel-wearer*. 



Sub-order DipmcOMOHB. 

 1 Sedentary '{ Tribe II TublUUriip : Tu- weavers, Includ- 

 ing Kcribellat* and Cribtllata-. 

 Tribe III.-Ri-tlt'lariir: Une-weaven. 

 , Tribe IV. Orbltollari* : Orb-weavers, Including 



Ecribellat* and Crlbellat*. 

 /Tribe V.-LaUrignd*. 

 Wanderers '1 Tribe VI migrate. 

 I Tribe VII. Halt (grate. 



Numerous extinct species of spiders have been 

 obtaine<l from Tertiary deposits, especially from 

 amber. The oldest known form (I'mtolycosa) 

 occur* in Carboniferous strata. 



Britwh Specie*. Among the British species the 

 following may be noted : The Common Garden 



Spider ( Kjirtrn diudrmn), and other species of this 



genus; the House spiders (Tegeiutria dometti 



T. riri/is) ; Aijclfna labyrinthtca, which makes large 



cobwebs, very abundant 



on heaths ; the Water 



Spider (Argyroneta aqua- 



ttca), which inflates its- 



sub-aquatic dome-shaped 



web with air brought 



from thesurfaceentangled 



among the hairs of the 



spiders body ; the Green 



Crab-spider (Sparasnu 



smaragdulus), whose 



young are fond of bal- 



looning in autumn even- 



ings ; a few Wolf -spiders, 



such as Lycosa iiiratica 



and DoloLde* fimbria- 



ttu; Salticvt scenicvs, 



exceedingly common on 



walls and fences, and Atyptu snlzeri, the only 



British representative of the Trap-door Spiders (see 



Systematic List : P. Cambridge, Proc. Linn. Soc., 



xxx. 1875). 



Relations to Man. The wide-spread prejudice 

 against spiders is not scientifically justifiable. We 

 must admire their dexterity, their instinctive apti- 

 tudes, their intelligence, the beauty of their archi- 

 tecture, the elaborateness of their courtship ( tragic 

 as it sometimes is for the suitor ), and their mater- 

 nal care. Although there are countless tales of 

 'black spiders,' rarely preserved for identification, 

 which are alleged to have given dangerously 

 poisonous bites, this is not true except in regard 

 to the famous Tarantula (Lycosa tarantula), and 

 even the effects of its bite have been grossly exag- 

 gerated both by evil intention and credulous super- 

 stition. Of a not uncommon line weaver (Lnt)tro- 

 dectus oculatus), which has a very bad reputation 

 as a venomous biter, one of the authorities on 

 spiders says that he repeatedly allowed himself to 

 be bitten "and suffered no inconvenience. In fact, 

 if we except the Tarantula, there are few spiders 

 more dreadful than are fleas. In old medical 

 practice a spider was sometimes applied to the 

 wrist in cases of fever, and another custom of 

 applying the web to staunch bleeding is still prac- 

 tised by schoolboys, who are happily ignorant of 

 antiseptic precautions. The great value of spiders 

 is the obvious one that they destroy so many 

 insects ; thus, McCook counted thirty -six mosqui- 

 toes on a single web. 



See especially H. C. McCook, American Spideri 

 and their Spinniny-work (3 vols. Phila. 1890-94); also 

 Bertkau, numerous papers trans, in A nnalt and Afaiia- 

 tine of Natural UMory ; Black wall, Britith Spidert 

 (Lond. 1861-64); E. Blancliard, Araehida( Paris, 1853- 

 64); P. Cambridge, article ' Antchnida,' Snegclo. Brit. ; 

 .1. H. Emerton, The Structure and Habit* of Spidert 

 (Salem, 187H); Hahn ami Koch, Die ArmOaMut 

 (Nuremb. 1 831-49 1 ; Hentr, Kpidtrt of the United State* : 

 O. Hermann, Uniiarnt Spinnen-Fauna (BudajieHt, 

 1879); K Keyserling, Die Spinnen Amerika* (Nuremb. 

 1880-86); Koch and Kcyserling, Die Araclmidtn Aiit- 

 tralieni ( Nuremb. 1872-88) ; Latrcille, Dugfe, and Milne 

 Edwards, Ararlinida of Ctirier'i JUijne Animal; H. 

 I I., rt. Bau und Leben der Spinnen (Berlin, 1878); 

 Moggridgc, Trap-door Spideri (Lond. 1872); Mcnge, 

 Prenauehe Spinnen ; O. W. and E. O. Peckham, Obter- 

 ration on Sexual Selection in Spidert of the / 

 Attidee (Milwaukee, 1889); E. G. Peckham, Proteetirt 

 Setemblanee in Spideri (Milwaukee, 1889); E. siu,,,n, 

 Lei AracHnidei de France (Paris, 1874-84); ThorelL 

 Kuropean Spideri ( Upula, 1870) ; and Walckcnaar and 

 Oervais, ffiitoire Nat urelle drt fnieetrt A ptfret ( 1837-47 ) ; 

 W. Wagner, L'lmluttrie dt Araneinn (]* 



See HK.SSKMKH, and STEEL. 



Spielberg* See UNX. 



