EXTERNAL ANATOMY OF INSECTS. 657 
the trunk, and these organs remained attached to the 
latter?. As to the Octopods and Arachnida, in the mites 
(Acarina) they are lateral, and in their analogues, the 
spiders (Araneidea), they emerge between the thorax 
and the breast, which last they nearly surround ; in the 
Phalangide the bases of the coxee approach near to each 
other, being separated only by a narrow sternum ; in their 
antagonists, Chelifer and Scorpio, they apply to each 
other, the anterior ones acting as mazille. In the 
myriapods the legs of the Chilopoda, and some Chilo- 
gnatha, as Glomeris, are inserted laterally, a single pair 
in a segment; but in Julus their attachment is ventral, 
the coxze seem to spring from a common base, and there 
are two pair to each segment’, except the three first, 
which bear each a single pair. ; 
I shall next consider how the legs are located with re- 
spect to each other. ‘To render this clear to you I shall 
represent each of the variations, which amount in all to 
twelve in the hexapods that have fallen under my notice, 
by six dots. 
1, :: In this arrangement the legs are all planted 
near to each other, there being little or no interval be- 
tween the pairs, and between the legs of each pair. It 
is exemplified in the Lepzdoptera, Blatta, and many 
Diptera. 
* Prate XXIII. Fie. 4. 
> Prare XXVII. Fic. 58. M. Savigny affirms that these insects 
cannot have, and really have not, but one pair to each segment ; only 
that the segments are alternately membranous and shelly, and that 
the former are concealed under the latter (Anim. sans Vertebr.1.i. 44.): 
but, pace tanti viri, I cannot discover that any suture separates these 
portions from each other: so that, admitting his theory, they must 
be regarded as two segments soldered together. 
VOL. [II. Dau 
