PULJIONAIUA. 



453 



hp.vc not been adojitcd as the ground-work of this arrangement, Chellfcr arjd Scorjiio 

 being united together, whilst in the fifth order we find the " Mites " (but no definition 

 is given to enable us to judge what group is thereby intended) separated from the 

 remainder of the Acarides, which form the sixth order. 



la this valuable work the author proiioses to treat of all the A])terou3 insects, exclu- 

 sive of the Crustacea ; but the first volume only is yet published. Distinguished as 

 its author has long been for his writings upun the iVratdniida *, the present work, form- 

 ing a portion of the Suites u Biiffon, is very valuable, as containing a mass of mate- 

 rials never before published, with the substance of the various works which the author 

 has already given to the world. Much interesting detail relative to the haljits of 

 these animals is here collected, and a great number of species as well as genera of 

 Spiders, arc described in this volume] 



THE FIRST ORDER OF ARACIIMDA,— 



PUHrONARIA, (Unogata, Fabricius),— 



Possesses, as above stated, a system of circulation well defined, and jiuhnonary sacs, always 

 placed beneath the belly, and externally indicated by transverse orifices (sti'jmftta), sometimes 

 eight in number, four on each side, but sometimes four or only two in number. The numljer 

 of simple eyes is six or eight f, whilst in the following order there are not more than four, 

 often two, sometimes very indistinct or even \\antiug. 



Tlic heart is a threat vessel, extending the whole length of the back, and ernhs branches on 

 each side, and in front.:]". The legs are constantly eight in number. The head is also sold- 

 ered to the thorax, and exhibits at its anterior and upper extremity tivo claws, (mandibles of 

 authors, but named chelicera or antennal claws b)' LatreiUe,) terminated h_v two fingers, one 

 of which is moveable, or by a single one, which forms a moveable hook.§ Tlie mouth is 

 composed of a labruin, (see the general observations on the class) ; two palpi, sometiim s 

 havin"- the a])pearanee of arms or clavi'-legs; two or four maxiUx, composed, wdien there are 

 only two, of the basal joint of the first pair of legs; and of a tongue of one or tMO parts. [| 

 r>v takine', as the ground of classification, the progressive diminution of the pubnonary sacs 

 and spiracles, the Scorpions, in which there are ciglit, (wlidst there are only four or Xko in 

 other Araehuida,) ought to form the first genus in the class ; and hence our family l-'e(lii)alpi, to 

 ^vhicli it belongs, ought to precede that of the spinning sjiecies (Araiieides), which arrange- 

 ment I adopted in my Families Nuturelles, and Dufour also is of a similar opinion. But 

 these last Arachnida are in some respects isolated, in consequence of their male organs of 

 o-eneration, the hook of their frontal clans, their abdnmen pedunculated, the spinnerets, and 

 their habits. The Scorpions, moreover, seem to form a natural passage between the pulmonary 

 Araebnida and the family of the Pseudo-scorpions, the fij'st of the foUowing order. Vfe 

 therefore commence with the Spinning Arachnida. 



1S05, 8vo ; tht Fii 

 Cl«tlijir„li,i:i •!•■• ■ 

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I siM'Pose llR- Intersil uii 

 t .Accordinu to M. M 

 Scorpion 



ttjue Fyi!i,r,ih. 



ides, 



the .An 



of ll. 



Km.. 



qoc, is described ns li^vim; only four cj'cs, but 

 oic-s wore overlooKcd. Sec Erc^iis. 



o! de Serres, Ibc blood in the Spiders and 

 rried drst to the rcsidratory orjians. and tbenee. by 

 10 the diffcrEiit [lart.s of tliC body. Brit fronr niialok-y 

 ieitli the Crustacea, the circulation is probably eflccted in the reverse 

 ii.anncr. (See Trcviranus on the anatomi- of these niiiinaJs.) 



J riicsc or^rans consist of a swollen basal joint, of which one of the 

 superior aoylcs (when llic claw is didactylc), is produced, forniiat,' 



the fjxed thuniii, and r.f a second joit 



able piece, either as an op|iosed finijer 



II That of the Scorpions appears to ci 



of an elonijateil, pointed triangle, prodi 



t. which constitutes the n.ovc- 

 >r as a simple h^ih. 

 tisist of four pieces in lhcsha;,e 

 eed in front ; but the t«olaieral 



ones are evidently formed of the first joint of the two fore-lc^, d 



may be considered as two ]na\illte anabijjoos to the two brst ina\ilhc. 

 In IMyjralc, Scorpio, &c.. tlie palpi aie G-joiiited, tlie hrst joint oi uhich, 

 in the other Spiders, is dilated to fitrm the inuxiUary lobe, riiis lobe, 

 even, in some species, is articulated at its base. If we iia,,s over ihn 

 joint, the palpi are ordy 5-jointed, as ordinarily dcserilicd. iji the 

 Scorpions the terminal moveable lini,'er of the claws lornis, as in tne 

 claws of the Crabs, a si.\th joiiit. 



