DIP TER A. 
443 
The larvae are gregarious, and live in fungi and in decay¬ 
ing vegetable matter. They may be found in the fungi 
growing on logs and 
trees, in the vegeta¬ 
ble mould among 
dead leaves, under 
bark, and sometimes 
in cow r -dung. They 
have eight pairs of 
spiracles. One spe¬ 
cies, Sciara mall 
(Sci'a-ra ma'li), feeds 
on ripe apples, es¬ 
pecially those that 
have been previously 
perforated by the 
Cod 1 in-moth. 
In this family the 
larva has a distinct 
head. The pupa is 
not enclosed in the 
skin of the larva; 
but in SOme genera ^* IG * 52 °-—Wings of fungus-gnats. (The drawings are 
& _ after Winnertz ; the lettering is original.) 
the transformations 
are undergone in a delicate cocoon. 
The larvae of some species of the genus Sciara often 
attract attention on account of a strange habit they have of 
sticking together in dense patches. Such assemblages of 
larvae are frequently found under the bark of trees. But 
what is more remarkable is the fact that when the larvae are 
about to change to pupae an assemblage of this kind will 
march over the surface of the ground, presenting the appear¬ 
ance of a serpent-like animal. Such a congregation is com¬ 
monly spoken of as a Sciara-army-worm. Examples have 
been described that were four or five inches wide and ten or 
twelve feet long, and in which the larvae were piled up from 
