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means of pruning-shears, the infested twigs at the time when they 
contain the pup^e. In 1905 the greater part of the larvae had pu- 
pated by the 3d of May, at which time, among 19 specimens, 18 
were pupae and only i was a living larva. An observation made on 
tlie 5th of May showed this to be about the height of the pupal sea- 
son, since all specimens seen were pupae except one. May 22, on 
tlie other hand, of 20 specimens, 18 were adults, i was a pupa, and 
I a larva not yet transformed. The last was probably parasitized. 
From observations of 1905 directed especially to that point, Mr. 
Taylor concludes that pupation begins, as a rule, with the begin- 
ning of the ripening of the seeds of the elm, and that the pupa is 
almost always to be found within two inches of the tip of the in- 
fested twig. In the only exception noticed it was about 2^ inches 
from the end. It is normally formed with its head towards the tip 
of the twig. In the only case seen to the contrary, the beetle form- 
ing within the pupal chamber had perished without coming out. 
The Beetle. — Our earliest date for the recently formed beetle is 
May 10, at which date one appeared in a breeding-cage and three 
were taken on trees at Decatur. As pup^c were found until May 22, 
the period of transformation is apparently about two weeks. The 
sexes were seen pairing at various dates between May 21 and June 
7, Adults began to die on the 29th of May, and the latest were 
seen alive June 11. The entire life of the insect in the beetle stage 
is consequently about a month. 
The l)eetles feed on the veins of the leaves, gnawing these away 
from the under side, thus sometimes making longitudinal slits 
through the thickness of the leaf (PI. VIII., Fig. e). This injury 
at Decatur was easily seen from the ground on looking upward 
through badly infested trees. In breeding-cages, wdiere the food 
was comparatively scarce, the leaves were thus riddled and killed, 
the petioles were eaten, and even the soft tip of the twig was 
gnawed into or eaten away. 
Although not readily provoked to take wing, the adults are of 
active habit, and have a good power of flight. Their slow dispersal 
is not due to any lack of locomotive power, but to what, in view of 
the destructive consequences to the species, we must look upon as 
an aberration of instinct. Though no trace of the beetles was found 
in some parts of Decatur where elms were abundant, they were so 
numerous in other parts of the town that a large percentage of their 
larvae could not mature in the infested trees. Several females were 
girdling the same twig and depositing their eggs there successively 
although there was an abundance of fresh material a little distance 
