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<fggs from the leaves of a young pear tree about as fast as upward of 50 
to 75 Psyllas laid them. The larvae of the ladybirds are equally active 
and beneficial, and I had no difficulty in rearing a brood from the eggs 
in my breeding cages on the eggs and larvae of the Psylla. 
It is possible that the disappearance of the Psylla in the orchard of 
Mr. Brown may have been in part due to the attacks of these two pre- 
daceous enemies, but while the great value of these two insects, 
particularly of the lace- winged fly larva?, in this direction can not be 
questioned, they could hardly have caused complete extermination 
which has probably been more correctly accounted for above. 
LIFE HISTORY OF THE LACE-WING FLY. 
The predaceous habits of the lace-wing fly larva? are of common 
record, and their beneficial character is well known, but in view of the 
important role played by this insect in the economy of the Psylla it is 
of interest to describe more minutely its life history and habits. The 
eggs, instead of being deposited in rather numerously placed clusters 
or groups, as is the case with some other species, are distributed 
almost invariably singly on the leaves, rarely two together on the same 
stalk. The stalk is also not half the usual length, not much exceeding 
three times the length of the egg proper. Judging from examinations 
made on my first and second visits, I should say that the egg period 
ranged from seven to ten days. The young larva cuts off the upper 
end of the egg on emerging and is surprisingly large in comparison 
with the egg from which it emerges. It is light ash-gray in color, the 
head abnormally large, and the body armed with immense curved hairs 
or spines which give it rather a ferocious appearance and makes it 
seem to the young Psylla undoubtedly as a veritable dragon. The 
body is long and tapers very considerably toward the tip, and the head 
is notable for what appear to be two large curved mandibles. It crawls 
down along the egg-stalk and begins immediately its active search for 
food. On approaching the egg or young larval Psylla it immediately 
grasps it between its long curved mandibles. These are really com- 
pound organs, being deeply grooved to inclose the maxilla?, which 
nearly equal in size, are of similar form, and play in the grooves of the 
mandibles. These organs form two sucking tubes, between the tips of 
which the egg or the young larva is held and rolled one way and the 
other, as between a thumb and finger, the juicy contents being in the 
meanwhile rajndly extracted. It is a most interesting sight to watch 
this little larva at work and to note with what celerity it grasps the 
young Psylla, quickly extracts the juices, and casts aside the dry shell, 
the whole operation taking frequently less than a minute. The larva 
is an extremely hungry one, is always feeding, and its rapidity in 
growth is limited only by the abundance of the food supply. It eats 
anything that comes in its way, is totally fearless, and is also, unfort- 
unately, cannibalistic, eating its own kind with as great readiness as 
