EXTERNAL ANATOMY OF INSECTS. 617 
respond with the secondary wings of the other Orders. 
It may be said, indeed, that in several instances both ¢eg- 
mina and hemelytra do not differ at all in substance or 
use from the wings that they cover. Thisis true; but as 
their structure’in other respects is the same with that of 
those that are more solid and less apt for flight, it was 
convenient to consider them under the same name. 
1. To begin with the articulation of these organs with 
the trunk ; in general it may be stated that this, as in 
tegmina and hemelytra, is usually by the intervention of 
three axes, formed by the conflux of the nervures of the 
three areas at the base of the wing, which either imme- 
diately or by other pieces are implanted in the trunk, so 
as to receive from it the aérial and other fluids, neces- 
sary for its expansion and motions*. Having given this 
general statement, I shall next apply it to the wings in 
some of the different Orders. If you carefully extract 
one from the stag-beetle (Lucanus Cervus) or any large 
species of the Dynastida, in the Coleoptera ; the first 
thing that will strike you, upon examining the base, will 
be the plate before mentioned called by Chabrier the 
humerus, which is a stout transverse corneous piece, with 
a deep sinus towards the wing, filled with ligament: if 
you again follow the costal, mediastinal, and postcostal 
nervures, you will find them unite to form an axis, con- 
sisting of three parallel pieces, which connects by its in- 
termediate internal piece with one end of this plate. The 
nervures of the Intermediate Area terminate also in a 
corneous axis at a greater distance from the base than the 
other two, which connects with Chabrier’s humerus by 
means of the ligament of the sinus just named. Those 
* Chabrier Sur le Vol des Ins. c. 1i. 325—. and 326. Note 1. 
