EXTERNAL ANATOMY OF INSECTS. 625 
margin of the wings of the former, vadzus and cubitus, as 
corresponding with the bones so named in the fore-arm 
of the latter, and the plate which often terminates these 
nervures in Hymenoptera, he names the carpus ; it may 
look like presumption to differ from two such weighty 
authorities, but as their observations seem to have been 
too limited, in one case to the Hymenoptera and Diptera 
only ; and in various Orders there is nothing analogous 
to the stigma or carpus, and all the other nervures of an 
insect’s wing have no analogue in that of a bird, but 
more especially as M. Latreille seems to think with me 
on this subject *, I have retained Linné’s term for the 
marginal nervure, and for most of the others have adopt- 
ed those of the great French Entomologist just men- 
tioned. I shall here only further observe,—and it seems 
to me an observation of prime importance, in the deter- 
mination of the question of the analogy of the wings of 
insects,—that they are not, as in birds, the fore-leg con- 
verted into an organ of flight, but, like the wing of the 
Draco, an organ superadded to the legs; and, further, 
that the connection is not with the fore-legs, but, as has 
been before observed °, with the two posterior pairs. 
The Costa © is usually the strongest of the nervures, 
and that upon which the wing seems to be built; but in 
some cases, as in Blatta, Scutellera, Cynips, &c., it is re- 
presented by the mere membrane of the anterior margin; 
in some Coleoptera, as in Geotrupes, Dytiscus, &c., its 
structure, except at the base, appears to be annular or 
nearly so, at least a vast number of corrugations, running 
transversely, are observable on its upper and lower sur- 
* N. Dict. d’ Hist. Nat. i, 251. > See above, p. 562, 575, 589. 
© Pirate X. hr. 
VOL. III. as 
