THE SUBSTITUTE. 
57 
from the same larva as Polyodon, 
and this error has been dropped in 
order to commit a fresh one, by 
referring Subluslris as a variety of 
Lithoxylea. There might possi- 
bly be also two species mixed 
nnder Rurea. All these errors are 
rectified by degrees; but a good 
monograph of this genus, only ad- 
vancing well-ascertained facts and 
accompanied by good drawings, 
especially of the larvae, would he 
far from a useless work to entomo- 
logists. (Vol. I., p. 136.) 
Dipterygia. 
I now perceive that I was 
wrong in placing the European 
species, which composes this ge- 
nus, in the genus Cloantha, of the 
family of the Xylinida, together 
with its ally Conspicillaris ; but a 
more profound study of the cha- 
racters, in convincing me of my 
error, has also shown me the im- 
possibility of leaving Pinastri in 
the same genus with Conspicilla- 
ris. Neither can I place it in the 
:genns Xylophasia, to which it is 
very closely allied. I have, there- 
fore, adopted the genus of Mr. 
■Stephens with the name borrowed 
ifrom that given to the species by 
iHirfuagel, in allusion to the 
l.markings at the anal angle, which 
11 little resembles a bird’s wing. 
I do not, however, conceal that 
ithis genus does not yet appear to 
[me to repose on well-defined cha- 
; racters. 
i According to the larvse this 
tgenus appears to approach rather 
to Axylia than to Xylophasia ; in 
fact, as in the former genus, the 
larva has the twellth segment 
rather raised into a pyramidal 
ilmmp. The spots are neither 
'tvarty nor shining ; and the larvte 
have not the vermiform aspect of 
the Xylophasia. They live con- 
cealed under the lower leaves, but 
not in the roots, nor do they con- 
struct oval cavities like these lat- 
ter. (Vol. I., p. 146.) 
Xylomyges. 
This genus has always hitherto 
been classed among the Xyli- 
nida, and has only recently been 
brought here. It seems, how- 
ever, much better placed here, and 
the Exotic species confirm this 
opinion. The larva; of Xylomy- 
ges have nut the earthy and ver- 
miform appearance of those of 
Xylophasia, and have more re- 
semblance to the larvae of Noc- 
tuida. Those of the Exotic spe- 
cies especially resemble the larvae 
of a Triphana or a Noctua, but 
we do not find in them the wedge- 
shaped spots on the twelfth seg- 
ment, which characterise so well 
these two latter genera. They 
always live, like those of the rest 
of the family, at the foot of low 
plants, but not buried amongst 
the roots. (Vol. I., p. 147.) 
Laphygma. 
This genus has hitherto been 
classed, in the system of European 
species, amongst the Caradrina, 
but it is evident that it cannot re- 
main there,in spite of the superficial 
resemblance lietween Laphygma 
exigua and Caradrina cuhicularis. 
The hyaline posterior wings, the 
crested abdomen, the form of the 
palpi, &c., all show that it cannot 
be united with Caradrina. The 
genus Laphygma is composed of 
species very nearly allied to one 
another, and which, though at 
present not numerous, are found 
nearly all over the globe. The 
