THE LOPHYRI. 
1 77 
spare for its larvae. The young larvae live in groups, and collect 
in great numbers ; they eat first of all the young shoots and buds, 
and finally do not despise the hardest foliage. Many of the trees 
they attack are soon terribly despoiled of their leaves, and have 
their existence endangered, and every now and then large forests 
of firs and pines are nearly destroyed by the ravages of this 
insect, which certainly chooses a strong tasting diet. 
The larvae of the Lophyri do not dig into the earth in order 
to undergo their metamorphosis, like so many of the saw-flies ; 
but they construct their cocoons upon the branches of the tree 
they have despoiled. The cocoons are grouped together on the 
stouter twigs of the trees, and are more or less oval in shape. 
They are often found empty, and one end opens like a trap-door. 
This is because the saw-fly, when ready to escape, cuts a nearly 
circular slit in one end, pushes up the flap, and flies off. 
The position of the oval shaped cocoons is shown in the 
engraving, and there are some perfect insects represented. The 
females are engaged in depositing eggs, whilst a male is flying. 
The larvae have the characteristic curl of the tail. 
Some larvae of the genus Lyda live in groups, and like the 
Lepidoptera under similar circumstances, protect themselves by 
forming a net-work of silk for the whole colony. The pear-trees 
are now and then much damaged by Lyda piri , whose larvae 
collect in great numbers upon the leaves, and spin a web in 
common to protect themselves. 
The Cephines are the second tribe of the saw-flies, and they have 
slender bodies. They live in the interior of plants when in the larva 
form, and thus imitate the peculiar habits of many caterpillars, 
and, as might be expected, they present similar peculiarities as 
regards colour and the development of the legs. The Cephines in 
fact exhibit so great an arrest of the growth of the membranous 
legs that they surpass nearly all caterpillars in this respect, and, 
indeed, they are almost like worms. The species of the genus 
Cephas have a compressed abdomen, and the ovipositor of the 
female is hardly visible, whilst the antennae are swollen at their 
ends, and composed of twenty-one joints. The commonest kind is 
Cephas pygmceus — a little insect of a third of an inch in length ; 
it is black, and has a yellow border to its third, fourth, and seventh 
M 
