398 
LEPIDOPTERA. 
which one may recognise every form of larva, but it will assist if we 
mention some of the more prominent. Caterpillars with rows of spiny 
processes (Plate XXVIII, fig. 1) are Nymphalidce; rather flattened 
“ onisciform ” larvse, densely clothed in short hair are Lyccenidce (Plate 
XXXII), smooth caterpillars with a distinct neck ar e Hesperiidoe (Plate 
XXXIII), smooth caterpillars with smooth processes on the head or body 
are PapilionidcB / uniformly hairy caterpillars are Arctiidce or Eupterotidce, 
smooth caterpillars with few short hairs are Noctuidce (Plate XXVIII, 
figs. 2—5) ; semi-loopers are also of this family (Plate XXVIII, fig. 13), 
whilst true loopers with two pairs of suckerfeet are Geometridce; large 
caterpillars with an anal horn or a bulbous prot'horax (Plate XXVIII, 
fig. 6) are SpMngidce; hairy caterpillars with erect tufts are 
Lymantriidce (Plate XXVIII, fig. 8), with lateral tufts are Lasiocampidce 
(Plate XLVI). Caterpillars, smooth or spiny, in which the lower 
surface is a gliding surface are Limacodidce (Plate XXVIII, fig. 10). 
Smaller caterpillars with few short hairs and hooks on the suckerfeet in 
a circle are Pyralidce (Plate XXVIII, fig. 7), Tineidce (Plate XXVIII, 
fig. 10) or Tortricidce (Plate XXVIII, figs. 11, 12). Large caterpillars 
with hair-bearing processes are Saturniidce (Plate XLII). Figures of 
all these types are given below, and a glance through the figures will 
show that there are distinct types but that they do not clearly delimit 
the families as other characters do, and vary very greatly in the limits 
of a large family like Noctuidce- in accordance with habits. 
The pupa is brown, the appendages usually firmly fastened to the 
body and not free, the parts not movable with the exception of some of 
the abdominal segments; an important character is the nature of the 
hooks at the apex of the abdomen which secure the pupa in the cocoon 
and enable the moth to emerge. Resistance to weather is the object of 
the Lepidopterous pupa and it is of a firmly chitinised and well protected 
kind. As a rule, a cocoon of silk, alone or with extraneous matter, or of 
agglutinated soil, is formed before pupation. 
There are three devices in the imago for locking the wings, both pairs 
being functional in flight. (1) The frenulum, a stiff bristle or group of 
hairs on the base of the anterior margin of the hind wing which engage 
in a catch or group of bristles ( retinaculum) on the lower surface of the 
forewing ; this is found in most Lepidoptera. (2) Expanded basal area 
of anterior edge of hindwing; found in Rhopalocera ; Lasiocampidce , 
