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LARVAE OF LEPIDOPTERA. 
By D. W. Coquillett. 
SECTION II. 
The larvae belonging to this section are commonly called cater¬ 
pillars ; their bodies are divided by impressed rings into about 12 
parts, called segments. These segments are numbered from the 
head backward; that is, the segment back of the bead is numbered 
1, the one back of this number 2, and so on. A few authors call 
the head the first segment, and the segment back of this number 
2; but this is, in our estimation, very inconsistent, and in the fol¬ 
lowing pages the segment back of the bead is always numbered 
1, and the other segments are numbered to correspond with this. 
Caterpillars are provided with from 10 to 16 legs; those which 
have the latter number have 6 legs under the fore part of the 
body, 8 under the middle, and 2 under the last segment. In those 
which have a less number of legs than 16, the legs missing are 
usually those under the middle of the body; in some which have 14 
legs, however, the legs under the last segment are either entirely 
wanting, or their place is supplied by a pair of short tubes. The 
legs beneath the fore part of the body are called thoracic ; those 
beneath the middle of the body, abdominal; and those beneath the 
last segment, the anal. 
In the descriptions certain terms are used which will need ex¬ 
plaining. The dorsal line is in the middle of the hack; the sub-dorsal 
line is midway between the dorsal line and the spiracles, or breathing 
pores, which are 18 in number, and are situated one on each side 
of the first segment, and of the segments from 4 to 11 inclusive; 
the stigmatal line includes the spiracles. The dorsal space extends 
from the dorsal line half-way to the spiracles; the sub-clorsal space 
extends from the spiracles half-way to the dorsal line; the stigmatal 
space is between the spiracles and the base of the legs, but this 
term is seldom used; the under part of the body is the venter. 
There is sometimes a polished spot on top of the first segment; 
this is called the cervical shield ; a similar spot on top of the last 
segment is called the anal plate. Piliferous spots are small raised 
spots or dots, usually of a brownish color, situated on various parts 
of the body. 
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