XXII 
THE HABITS AND STRUCTURE OF MOTHS. 
There are also frequently various accessory appendages. The 
pectinations often have cilia, arranged uniformly on both 
sides, and the teeth of dentated antennae frequently termi¬ 
nate in short, brush-like cilia. 
The thorax is attached to the head in front, and the abdo¬ 
men behind. We can generally distinguish a front part, or 
collar, and two lateral portions, the tegulae, which cover the 
base of the wings. The scales are often arranged on the 
thorax in such a manner as to form crests on the back. 
The abdomen is composed of six or seven segments joined 
at the incisions. The scales are frequently aggregated above, 
at the sides, or at the extremity, so as to form tufts. 
The legs are formed of the following parts: the coxa is the 
part which is attached to the body, next comes a small joint, 
called the trochanter, which is followed by the femur, tibia, 
and tarsus. The tibiae have usually two spurs or calcares at 
the end, and the hind ones frequently have two additional 
spurs beyond the middle. The front tibiae sometimes have 
a ridge on the inner side, and this may be prolonged into 
a spine. 
There are two pairs of wings, which are occasionally rudi¬ 
mentary in the females, as in those of the Yapourer Moth 
(Orgyia antiqua ), or entirely wanting, as in many Psychidae. 
The fore wings lie with their inner margin on the front 
margin of the hind wings, which they usually overlap, when 
the moth is at rest. The hind wings are often folded when 
at rest. Near the base of the costa of the hind wings we fre¬ 
quently find a stout elastic bristle, sometimes double, which 
is connected with a hook on the under side of the fore wings. 
It is called the frenulum, and serves to connect the fore and 
hind wings. It is never met with in butterflies. 
The front border of the wings is called the costa ; the hind 
border, the inner margin; and that furthest from the body, 
the hind margin or outer margin. The narrow portion of the 
wings, next the body, is called the base. The angle between 
the costa and the hind margin is the tip or apex; that between 
the hind and inner margins, the hinder angle in the fore 
wings, and the anal angle in the hind wings. 
In many Tinese there are only two margins, because the 
wings are very narrow and lanceolate, and the margin is 
gradually curved from the apex to the base. 
The membranous part of the wing is limited by the mar¬ 
ginal line, and the scales which are situated beyond this, are 
called the fringes. In some of the Microlepidoptera, espe¬ 
cially in those with narrow hind wings, the fringes are hair¬ 
like and very long, those of the hind wings being often longer 
