SYSTEM OF INSECTS. 381 
dividual you may exclaim — This is aNeuropterous insect. 
The only one that I have been enabled to seize is, that 
their scapula and parapleural are parallel and placed 
obliquely a . Whether, with all this puzzling variation 
and dissonance between the different tribes of which it 
is now composed, this Order can be considered as a na- 
tural group, in the present state of our knowledge it 
would be rash to decide. I shall observe, however, that 
the Libellulina, — whether we regard their metamorpho- 
sis and the singular character before described that di- 
stinguishes their larva and pupa b , their oral instru- 
ments , the remarkable position of their legs d , their 
general form, the wonderful and peculiar machinery by 
which their wings are moved e , and other circumstances 
of their internal anatomy, — if any are to be regarded as 
forming a separate Order, are the first entitled to that 
distinction. At present, with our friend Mr. MacLeay, 
I shall consider it as not further divisible, and as consist- 
ing of five principal forms. I must not omit to observe, 
that in the Ephemerina the parts of the mouth, except 
the labrum and palpi, appear to be mere rudiments f . 
Def. Metamorphosis varying. Larva a hexapod. 
Wings four in most, and reticulated with nu- 
merous areolets. 
Prothorax distinct. 
Scapula: and Parapleural parallel and oblique. 
Tail of the female without a terebrant, or pun- 
gent multivalve ovipositor s. 
a Vol. III. p. 563. b Ibid. p. 125—. 
c Ibid. p. 423, 441—, 451, 454—. d Ibid. p. 656. 
e See above, p. 186—. ' N. Diet, d? Hist. Nat. x. 344. 
K The ovipositor of Rapkidia seems merely calculated to introduce 
its eggs under bark ; it seems incapable of boring. 
