EXTERNAL ANATOMY OF INSECTS. 708 
9:7. Perga?. 11:7. Phasma. 
9:8. Perga ¢. 11:9. Chelifer. 
10:7. Locusta 2. 12:11. Thelyphonus. 
10:8. ——_—¢. Many. Myriapoda. 
10:10. Mshna. 
I shall next explain the articulation of the segments 
with each other, both that of the rings formed by the 
union of the dorsal and ventral pieces, and that of those 
pieces themselves. In general it may be stated with re- 
spect to the former, that each ring is suspended by liga- 
ment to that which precedes it; but this takes place in 
three ways—in some the margins of the suspended rings 
touch each other only, with little or no znosculation ; 
in others the dorsal segments only touch, and the base 
of each ventral is covered more or less by the apex of 
the preceding one; and in others again the base of the 
whole ring, both above and below, is so covered, or 
inosculates. The first kind here mentioned you will 
find exemplified in Melolontha, Geotrupes, Musca, &c. ; 
the second in Scorpio; and the third in Staphylinus, the 
Hymenoptera, and many others. In the Coleoptera, says 
M. Cuvier, speaking of the movements of the abdomen, 
the rings only touch each other at the margin, and the 
movement is very limited; whilst in the Hymenoptera 
they are so many little hoops, which inosculate in each 
other as the tubes of a telescope, one third only of 
their extent often appearing uncovered?. We see the 
reason of this structure when we consider the calls they 
have for greater powers of movement in this part in lay- 
ing their eggs, and annoying their enemies and assail- 
* Anatom. Compar.i. 451. 
