PULMONARIA. 
453 
I have not been adopted as the ground- work of this arrangement, Chelifer and Scorpio 
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. 
In this valuable work the author proposes to treat of all the Apterous insects, exclu- 
sive of the Crustacea ; but the first volume only is yet published. Distinguished as 
its author has long been for his writings upon the Arachnida * * * § , the present work, form- 
j ing a portion of the Suites d Buffon, is very valuable, as containing a mass of mate- 
I 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 habits of 
these animals is here collected, and a great number of species as well as genera of 
Spiders, are described in this volume.] 
THE FIRST ORDER OF ARACHNIDA,— 
PULMONARIA, (Unogata, Fabricius), — 
Possesses, as above stated, a system of circulation well defined, and pulmonary sacs, always 
placed beneath the belly, and externally indicated by transverse orifices {stigmata), sometimes 
eight in number, four on each side, but sometimes four or only two in number. The number 
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 wanting. 
The heart is a great vessel, extending the whole length of the back, and emits branches on 
each side, and in front. J The legs are constantly eight in number. The head is also sold- 
ered to the thorax, and exhibits at its anterior and upper extremity two claws, (mandibles of 
authors, but named chelicera or antennal claws by Latreille,) terminated by two fingers, one 
of which is moveable, or by a single one, which forms a moveable hook.§ The mouth is 
composed of a labrum, (see the general observations on the class) ; two palpi, sometimes 
having the appearance of arms or claw-legs ; two or four maxillae, composed, when there are 
only two, of the basal joint of the first pair of legs; and of a tongue of one or two parts. || 
By taking, as the ground of classification, the progressive diminution of the pulmonary sacs 
and spiracles, the Scorpions, in which there are eight, (whilst there are only four or two in 
other Arachnida,) ought to form the first genus in the class ; and hence our family Pedipalpi, to 
which it belongs, ought to precede that of the spinning species {Araneides), which arrange- 
ment I adopted in my Families Naturelles, and Dufour also is of a similar opinion. But 
these last Arachnida are in some respects isolated, in consequence of their male organs of 
generation, the hook of their frontal claws, their abdomen pedunculated, the spinnerets, and 
their habits. The Scorpions, moreover, seem to form a natural passage between the pulmonary 
Arachnida and the family of the Pseudo-scorpions, the first of the following order. We 
therefore commence with the Spinning Arachnida. 
* See his Faune Parisienne, lusectes, f. 2 ; Tableau des Araneides, 
1805, 8vo ; the Faune Franqaise, and Mimoire sur une Nouvelle 
Classification des Araneides, in the Annals of the Entomological 
Society of France. 
t Tessarops, Rafinesque, is described as having only four eyes, but 
1 suppose the lateral ones were overlooked. See Eresus. 
t According to M. Marcel de Serres, the blood in the Spiders and 
Scorpions is carried first to the respiratory organs, and thence, by 
peculiar vessels, to the different parts of the body. But from analogy 
with the Crustacea, the circulation is probably effected in the reverse 
manner, (See Treviranus on the anatomy of these animals.) 
§ These organs consist of a swollen basal joint, of which one of the 
superior angles (when the claw is didactyle), is produced, forming 
the fixed thumb, and of a second joint, which constitutes the move- 
able piece, either as an opposed finger or as a simple hook. 
II That of the Scorpions appears to consist of four pieces in the shape 
of an elongated, pointed triangle, produced in front ; but the two lateral 
ones are evidently formed of the first joint of the two fore-legs, and 
may be considered as two maxillae analogous to the two first maxillae. 
In Mygale, Scorpio, &c., the palpi are 6-jointed, the first joint of which, 
in the other Spiders, is dilated to form the maxillary lobe. This lobe, 
even, in some species, is articulated at its base. If tve pass over this 
joint, the palpi are only 5-jointed, as ordinarily described. In the 
Scorpions the terminal moveable finger of the claws forms, as in the 
claws of the Crabs, a sixth joint. 
