45G 



^RACHNIDA. 



were not kiio\Aii in Italy, we consiiler with Alouffct that the Lycoire, and other large Spirlers uhich 

 do not construct webs, as well as the Solpuga;, are the animals collectively known under the former 

 name, and of which several species were described by the ancients. Lister, who first sti.uhed the 

 Spiders -which inhabit Great Britain -with great care, laid the base of a natural di&tril)ution, of which 

 those more recently published are mostly only modifications ; our more recent acquaintance with some 

 species peculiar to warmer climates, such as as the Mason Spider, described by Sauvages, and other 

 analogous species, the employment of the organs of tlie mouth, introduced by Fabricius, a more ju'c- 

 cise study of the eyes and their relative sizes, and the relative length of the legs, have contributed to 

 perfect their arrangement. M. Walckcuaer has entered into very minute details relative to these 

 animals, so that it is difficult to detect a species wdiich -will not enter into the groups which he has 

 proposed. The presence or absence of a third unguis at the extremity of the tarsi affords another cha- 

 racter not yet sufficiently generalized, of which, however, Savigny has given a shght sketch (see 

 "VValckenaer, Faun. Fran^., note at the end of the genus Attus). 



M. L. Dufour, who has published cxceUent memoirs upon the anatomy of these injects, and 

 especially studied those of tlic kiiigdom of Yaleiicia, -\^lle^e he has discovered many new species, has 

 paid particular attention to the respiratory organs of the Arachuida, and it is after his remark that we 

 di-vide them into those wliich have four pulmonaiy sacs, with four external spiracles, t^vo on each side 

 close together, and those -\vhich have only two.'''^ 



The first of these groups, which includes the Araneides ihcraphoHes of AYalckeoaer, and some goiera, 

 for which he has employed the collective name of Araaea, compose, in our method, the single genus — 



]\Iygale. 



The eyes are always situated at the anterior extremity of the thorax, generally close together. The 

 chehcer^ and legs are rolnist. The majority have only four spinneretsf; the two lateral ones are situ- 

 ated rather above the t-\vo others, and are longer and 3-jointed, not computing the elevation ^^hiell 

 forms their footstalk. They form silken tubes for their abode, v\'hich they hide either in the earth 

 into which they have burrow^ed, or under stones, in the bark of trees, or amongst the leaves. 



The Theraphoses of Walckenaer form a first division, characterized by four spinnerets, the tvi^o inter- 

 mediate and inferior generally very short, and the two exterior much exserted; the hooks of the 

 cheliceree folded beneath, along the under side, and not along the inner surfaces. Eight eyes in all, 

 generally arranged upon a small eminence, three on each side, forming a reversed triangle, of -which 

 the two upper ones are close together; the two others in a line between the iirectdmg. The fourth 

 pair of legs and then the first pair are the longest, the third the shortest. 



Those species which have tlie palpi inserted at the superior extremity of the maxillre so that they appear to be 

 six-jointed, the Ijasal joint being long and narrow, and acting- as the maxilla; the tongue, always small, 

 and nearly square^ and the two fore tiblai of the males with a strong spine beneath at the tip, form the restricted 

 genus — 



il/y(/a/e, Walck., — some of which lia\'e not a transverse series of moveable, corneous spmes at the upper 

 extremity of the cliehcene, aliuve the plaee of insertion of the terminal hook. The hair on the under-side of 

 their tarsi forms a thick cushion, f!;enerally hiding the ungnes. These are the largest species of the fanhly, some 



by Lrtt 



' [The a 



iT,t;en,erit of llie Spkltrs piven Ln- M. W^ii-jkenaer, i 

 The rollowinj^ is an abntract of his tabular synopsi 



5 last work, above referred to, differs in some respects from that omploynl 

 Oruups nrT'injjrjfl ac- 



Theraph.,sea .{ F.ighl ey, 



■ \ Eiijht eyL- 



G CD era. 

 , FilistEltt, tec. -1 , 



"S t 



f Eyes near toijethcr . . 



■IKyesspi.rt M,,sulc.r. I" 



J Eye-s frnntal ].)v«'li:ta, &c Tubiculei 



• iEye« frontal and latera) . Uiiiioics, S;c UcllviliLoles ■ ■ ■'( 



Eyes froutiii and lateral, "(^ Lyeosa, Dolophonea, &c. Courcuses. ... 



unequal J Eresus. Alms, &e. . . . VolUfjcu.scs ... 



fThumisus, S|.MnS3as,i«c. Ma^t■htu^es . . J 



Cluliiona, &t: Nidileles . . . .\ 



Pholcus, &c riliitlcs . . . . 1 



TfL'-eiiaria (Araiiea), &c. Tai.iteles . . . .1 



■■ ■- N:,i.r.k.s . . . .( 



Liiiyphia 

 Ari.'-ua, &c, 

 ^Arffyroueta 



Ri.n 



Nagcuscs 



Acpatiques.] 



[Mr, M'Leay, in an article upon Bome new forms of Arachnida, published Sn the Annals of Natural Nis/nnj, has thrown doubts upon tlie 

 pCDcral character given of these groups, fij;uriiig one species with only two eyes [Nops OuanabacciB) ; another, with tlie sternum divided into 

 three distinct .segnients, and one pair of the eyes enormously large [Dcinupis Lamia) ; another with the bend, thorax, and ;.bdonicii npparently 

 fiTlitulated [MT/rmnrachne meliinocepkalfi) ; und anotijcr with the fore-legs modified, in structure short, thicKcLicd, and composed of only sii 

 Instead <if seven joints {Otiothops fVatckenaeri) .} 



■\- I have observed in Atypiia the vesliRes of two otln-r [ii|iples, being- tho.'ie which in the Spiders of the fullondng division Lire placed betnccn 

 the four cAtenor ones, and ;ire very visible ; but at, they art here scarcely apparent, I have not counted Iheiu a, sncli. 



