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view Park, nor the grounds of Millikin University, in the outskirts 
of the town. The slow spread of the beetles was shown, not only 
by their destructive abundance in some parts of this town and their 
virtual absence in others, but also by the fact that of trees standing 
side by side some showed scarcely a trace of injury while others 
were badly damaged. The beetles can fly vigorously, and were 
sometimes seen on the wing; but they seem to lack the dispersal 
instinct — a fact the more remarkable because they are extremely 
intolerant of each other's company, both males and females attack- 
ing each other ferociously and devouring one another so readily 
that they can not be kept together in confinement. 
The injury to the elm begins late in May. On the 23d of that 
month in 1902 a few fallen twigs bearing fresh leaves were first 
noticed at Decatur, and others recently girdled but not yet fallen 
were seen on the trees. It is most abundant early in June, com- 
monly from the ist to the 5th, and may continue to the 24th of that 
month, after which date, in 1905, it was practically over for the 
season. It was noticed by Mr. Titus that rains and cool weather 
stopped the work of the beetles, sometimes for two or three days 
at a time. 
Besides its injuries to the common American elm (Ulmiis 
aiiicricaiia), this insect was seen at Decatur infesting, in the same 
way, cherry-trees, both sweet and sour, and it was once found in a 
peach-tree at the same place. Red elms, on the other hand, grow- 
ing among badly infested white elm-trees, showed no traces of the 
attack, and raspberry plants, liable to infestation by another species 
of the genus, were absolutely refused by beetles of this species kept 
in confinement and offered no other food. 
Experiments made by Mr. Titus in May, 1903, showed that 
this beetle will not breed in either dogwood stems or raspberry 
canes. For example, three pairs of specimens, male and female, 
which had been bred at various dates from elm twigs, were placed 
May 20 on a growing raspberry plant out-of-doors under a bell 
jar. The beetles were noticed pairing, but May 29 all were 
dead, leaving no trace of eggs or preparations for their deposit on 
the plants, and no evidence of any attempt to feed on the leaves 
except a little gnawing of the midrib of one leaf. When beetles 
were shut up under glass with twigs and leaves of the elm the in- 
sects fed and bred cjuite as freely as if at large. 
