369 
1916-17.] The Family Ghermesidse. 
“ wool ” for the protection of her fifty to one hundred eggs. The egg- colour 
varied with the age of the egg, yellow when laid, gradually becoming 
greener and darker until a brownish -green colour was reached. Before 
the end of May the effect of the feeding of the fundatrix was clearly 
visible. The needles of the opening bud remained stunted ; chlorophyll 
production was impeded, and the tips of the needles became a bright rose 
colour. The growing point was usually killed. 
Generation II. Gallicola . — The eggs batched out from 1st June 
onwards. Short “ wool ” was secreted by the light green larvae. These 
larvae continued to hatch until the end of June, but most of the galls had 
closed up by mid- June, so that larvae hatching later had to remain outside 
the gall. These larvae did not develop, and finally died. Their presence 
on the outside of the gall was characteristic for this genus, and probably 
due to the greater rapidity in the formation of the gall as a result of 
the fundatrix being situated actually on the gall. The rate of development 
within the gall varied as follows : — 
A. In a gall produced by a fundatrix hatching from a fertilised egg' 
development was rapid ; the three moults took place at intervals 
of five to seven days. Such galls turned brown and opened 
from 5th to 12th July. The nymphs climbed out and the final 
moult took place, generally in the morning. The wings of the 
red adults had straightened and firmed by early afternoon, 
when the principal migration of the da}^ took place. The 
progeny of each experimental gall was dealt with as described 
in “ Technique ” (Section I, 4). Eggs were only laid on spruce 
when the twig was sleeved, but the gallicolm settled readily 
on the larch needles and laid twenty to forty dark brownish- 
green eggs. Practically no “ wool ” was secreted by the 
gallicolse. After fifteen days all the eggs laid on spruce had 
shrivelled up without hatching, while those on larch had 
hatched. 
B. In galls produced by fundatrices hatching from eggs laid by 
gallicolse development was slower and variable. At the time 
of the opening of those of Group A the larvse in those of 
Group B were in the second stage. In some of the latter the 
next two moults took place at intervals of about seven days, 
and the galls opened around 25th July ; in others the develop- 
ment was slower, and galls of this type continued to open 
during August until the 20th of September. The progeny of 
vol. xxxvii. 24 
