382 SYSTEM OF INSECTS. 
= 
tatives in this Order. Though the number of wings is 
its prominent feature, yet there are two-winged insects 
in other Orders, as some Ephemere; and the Eprobos- 
cidea of Latreille seem rather a kind of winged Aptera, 
if we consider their ¢rophi, than real Diptera; or they 
may form an osculant group, partly winged and partly 
apterous, between the two. I have before remarked, 
that though, apparently, the insects of this Order 
have only two wings, yet the under or secondary wings 
of the other Orders have in them their representative *. 
Their poisers also, I formerly observed to you, are pro- 
bably more connected with their respiration than with 
their flight”. 
Der. Metamorphosis incomplete, or coarctate. 
Mouth proboscidate*. 
Prothorax replaced by a collar. Sutures of the 
trunk mostly spurious?. 
Wings two, with winglets attached to them: 
neuration various*®. Pozsers. 
Tarst pentamerous. 
Ovipositor various‘. 
11. APHANIPTERA §& (Aptera L. Lamarck. Rhyngota F. 
Suctoria Latr.). ‘This is an osculant Order, and is dis- 
tinguished from the other Aptera L. in undergoing a 
regular metamorphosis. The larva is vermiform, the 
pupa incomplete, and inclosed in a cocoon. Probably 
* Vor. I. p, 358—. » Ibid. p. 359. 
© Vor. III. p. 466—. 4 Tbid. p. 554—. 
* Ibid. p. 634. f See above, p. 157. 
® From aQeyns, inconspicuous ; so named because something like 
elytra appear. 
