Reports to the Board of Agriculture. 167 
said that one female may lay as many as one hundred and twenty 
eggs. 
The larvae hatch in from two to three weeks and appear towards 
the end of May and in June; by the end of June or in July they 
reach their full-fed stage and then pupate. 
The larvae (Fig. 25, V) are nearly an inch long when full fed, and 
like all the larvae of this genus they have twenty-two legs. They are 
at first pale green, almost whitish beneath, and with black sucker-feet, 
but as they mature they become dull brownish-green, with dusky marks 
above the pro-legs, and with a dark brown head ; the sucker-feet are 
yellow, with a brown line at the base. The first brood feed for from 
five to seven weeks, and then pupate amongst the needles or in 
cracks and crevices of the bark, the pupa lying in a cocoon of 
compact brown silk. These cocoons are very variable in colour, 
a 
some being almost black, others dull brownish-grey. They are about 
a quarter of an inch long, hard and compact. In many cases these 
cocoons remain over the winter, but they may give rise to a second 
brood of flies in July and August ; the progeny of the second brood 
spin their cocoons mainly amongst the fallen needles, moss and 
heather beneath the trees. These ground cocoons often occur in 
bunches, and like those of the first brood are very variable in colour. 
The larvae which form these cocoons do not enter the pupal stage 
until the spring. As many as seventy have been found together 
beneath moss and heather. 
When the Sawfly is ready to emerge it cuts a large circular slit 
in the top of the cocoon and escapes ; the top opening like a lid of 
a box on hinges. 
o 
