APTERA. 
Wingless insects, the mouthparts mandibulate. Antennae and legs simple, 
the integument soft, clothed in scales or hairs, the segments 
undifferentiated and little co-adapted. There is no meta¬ 
morphosis, the development being gradual. 
The order includes only a small number of minute wingless insects 
of extreme delicacy, supposed to be scavengers. The mouthparts are 
concealed, formed for biting. The legs are often long, and there are 
frequently abdominal appendages in the form of cerci, springs, etc. 
The body may be completely clothed with fine scales. There is no meta¬ 
morphosis and no changes take place in external appearance during life, 
except growth in size. Most of them live in concealment, their food con¬ 
sisting of dried or decaying vegetable matter, so far as is known. None 
are of importance economically, one genus, Lepisma, being a minor 
household pest. 
Aptera are divided into two suborders and eight families. The 
Thysanura have ten abdominal segments and consist of four families. 
The Collembola have six abdominal segments with a peculiar tube-like 
structure below the first. 
Campodeid^:. 
The abdomen terminates in a pair of pointed cerci; the 
mouthparts are concealed . 
The cosmopolitan insect Campodea staphylinus Westd. (Fig. 1) or a 
form very close to it occurs in India in damp moss, among damp decay¬ 
ing vegetation and in similar positions. It is a slender white insect, 
with moderately long antennae, with cylindrical body and with two 
anal cerci. 
