372 SYSTEM OF INSECTS. 
indeed we admit M. Latreille’s idea, adopted by Mr. 
MacLeay®?, that a varied metamorphosis is its essential 
character ; or, to speak more largely, variety itself seems 
the characteristic of the insects composing it, in every 
state; and there is scarcely a common distinctive charac- 
ter in their perfect state, upon detecting which in any in- 
dividual you may exclaim—Thisisa Neuropterous insect. 
The only one that I have been enabled to seize is, that 
their scapula and parapleure are parallel and placed 
obliquely®. 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 Lbellulina,—whether we regard their metamorpho- 
sis and the singular character, before described that di- 
stinguishes their larva and pupa‘, their oral instru- 
ments’, the remarkable position of their legs*, their 
general form, the wonderful and peculiar machinery by 
which their wings are moved‘, 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&. 
* Hor. Entomolog. 433. 6 Vor. IIL. p. 565. 
© Ibid. p. 125—. ¢ Ibid. p. 424, 442—, 452, 455—. 
© Ibid. p. 657. * See above, p. 18]—. 
& N. Dict. d’ Hist. Nat. x. 344. 
