Groups of the Lepidoptera. 339 
The only way in which it was possible to join on to the 
Bombyces, both Geometre and Noctuce, was to divide the 
first-named group, and fasten the Geometre to one part, 
the Noctue to the other. M. Guenée had even more 
recently been engaged upon the G'eometre, and no re- 
arrangement of this group was likely to be proposed by 
him, On the arrangement of the Bombyces, however, he 
was unfettered, having published no views upon the order 
of that group. 
This measure of dividing the Bombyces once determined 
on, all the details were, it seems to me, matters of ne- 
cessity. The Platypterygide have affinities both with the 
Bombyces and Geometre ; and that family, therefore, would 
not occupy an unnatural position, if made a connecting 
link between the two groups. This happy invention of 
the Platypterygide, was the only thing wanted. Hvery 
one knows to which family of Bombyces the Platyp- 
terygide have always been considered akin. ‘Their larva 
was described by Linnzus himself, as ‘ Vinule affinis” 
(Syst. Nat. vol. 2; p. 860); and Prof. Westwood suc- 
cinctly expresses the relationship of the groups, when 
he says (Westw. Intr. 11. p. 362), “ Platypteryx agrees with 
Geometra in the habit of the imago, but in its transforma- . 
tions it is much nearer to Cerura, amongst the Bombyci- 
de.’ Therefore the Notodontide (the family including 
Cerura) came naturally to be the separated section. Thus 
we have our new order worked out. 
Although this arrangement secures its objects, I ven- 
ture to think that it effects them in an empirical fashion ; 
and also fails in effecting what an arrangement of the 
Lepidoptera should secure. 
In the front of my objection, I of course place this 
starting of the Noctde from a few Bombyces, in order to 
preserve the order of the former group. But that has 
been sufficiently discussed. The erection of the family 
Platypterygide into a group, I confess appears to me a 
strong step. No author has yet described the Pla- 
typterygide as a separate group, not even Mr. Newman, 
who has faithfully followed the new order. He joins this 
family to the Pseudo-Bombyces, and calls both together 
“* Cuspidates,” a name he however explains is not a very 
good one (Brit. Moths, p. 204). The erection of the 
insect Aventia flecula into a separate group is also a very 
strong proceeding, and I much question whether both 
