Groups of the Lepidoptera. 337 
We are next taken through the Geometre, and there 
find numerous families of moths whose wings are thin 
and weak, whose bodies are slender, whose antenne are 
simple or filiform in the males, whose wings in repose 
are extended, or put up vertically, whose larva has ten 
legs, and cannot walk without looping. We are then 
again brought back to an isolated set of twenty-seven 
moths agreeing with the families from which we first 
started, having strong and thick wings, robust bodies, 
pectinate antenne, wings in repose meeting roof-like, 
whose larva has sixteen legs. 
The reasons for this startling arrangement, if I am at 
liberty to guess them, centre in this, that between the 
Geometre and the twenty-seven Bombyces, a connection 
can be made by means of Platypteryx. In other words, 
we are taken from the Bombyces by a leap into the Creo- 
metre, in order to be shown by what easy stages we can 
be brought from the Geometre back to the Bombyces 
again! The fact that Platypteryx joms Geometra and 
Bombyz is thus made the most of; but, even so, the new 
order has, as it were, a rough edge, because the junction 
of the true Bombyces (or Nocturni) with Geometra is not 
effected by closely related species. 
Now, let me endeavour to account for this extraordi- 
nary group Pseudo-Bombyces. No one has vouchsafed a 
line of explanation, and it is not my fault if I am all 
abroad. 
The arrangement of the Noctuc, in the different books, 
had been conceived with a view to the position of the 
group between the Bombyces at the one end, and the 
Geometre at the other. The species least akin to the 
Geometrcee had been put furthest away from the Geometre ; 
the species least akin to the Bombyces furthest away from 
the Bombyces. In the year 1852, M. Guenée—who in 
1841, as we have seen, followed the same arrangement— 
described or catalogued the Noctuc in this, the old order, 
beginning with the species akin to Bombya. M. Guenée’s 
work has taken its place as the chief work upon the 
Noctwe ; and the author of it would not, it may be ex- 
pected, be inclined, shortly after the book’s completion, 
to favour a new arrangement, which would render it less 
an authority. 
The affinity between the Geometre and the Bombyces 
seems in, or just before 1859, to have struck M. Guenée 
as of greater importance than he had before considered 
