the Larvae of the Noctuae. 27
peculiarity of looping up the back when in motion; "this
habit is lost after the first moult. (First Annual Report,
1869, pp. 73, 74.)
Leucania unipuncta, Haworth (the "army worm," = L.
extranea, Guenee). Newly hatched larva has "two front
pair of prolegs atrophied, so as to necessitate looping in
motion." Still geometriform in second stage. In third
stage looping habit lost, "but the front prolegs are still
somewhat the smallest." In the fourth stage the claspers
are of nearly equal size, and in the sixth stage the front
claspers are said to be, if anything, longer than the hind
ones. (Eighth Annual Report, 1876, pp. 184, 185.)
Leucania albilinea, Guenee. Newly hatched larva "quite
a looper, the prolegs or joints 6 and 7 being still more atro-
phied, and those on joint 8 being short."5 Looping habit
lost in second stage. (Ninth Annual Report, 1877, pp. 53
and 56.)
All these facts point to the conclusion that the Nocture
have been derived from geometriform ancestors, so that this
group is phyletically younger, i.e., has made a further ad-
vance in the development than the Geometrae. The geome-
triform sections of the Nocture are thus the more closely
related to the Geometrae, and, as already insisted upon by
Mr. Lockyer in the note referred to,6 should therefore follow
this last group, as in Stainton's list. The higher groups of
Bombyciform Nocture (Thyatira) approach the Pseudo-Bom-
byces in the attitude assumed by the larva when at rest, as
well as in the characters of the imago. If, therefore, the
Psychidae be referred to the Tineina, the following arrange-
ment appears to me to best represent the existing state of
our knowledge, although, of course, further investigations of
larval ontogeny may lead to other modifications:—
5 The author does not consider the head as the first segment, so that
segments 6, 7, and 8 correspond with segments 7, 8, and 9 of English
entomologists.
6 Mr. Lockyer draws the conclusion that the Geometrae are "undeveloped
Noctuae" an expression which appears to me misleading, as it implies
that the existing Geometrae; are in course of transformation into Noctuae.