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grown larvae, the larvae occurring in great numbers surrounded by the 
flowing turpentine. Trees thus infested were still living but the injury 
will probably cause a diseased condition of the trees, which will attract 
other species and result in their final death, thus we may be on the eve 
of a new destructive invasion like that which has just passed. Other 
species, like Polygraphia rufipennis, Tomicus calligraphus, and Tomicus 
cacographus, which are capable of existing in green, sappy bark, oc- 
curred in such abundance in the dying spruce and pine trees last 
spring that it is evident they must exist in the forests in great num- 
bers, and are ready to attack trees showiug the slightest indication of 
disease or weakened vitality, if they do not make a primary attack. 
Therefore, the imported enemy will find abundant food and favorable 
conditions for its rapid increase in the infested bark of felled trees, 
tops, and stumps in lumbering regions in which or near which the 
colonies have been placed. 
The imported Olerid does not confine itself to one or two species of 
bark beetles in one kind of trees, but the adults, it would seem, will at- 
tack and devour the adults of any species of bark and timber beetles 
found in the United States, and their larva will feed on the eggs, larvae, 
pupae, and young beetles of any species infesting the bark of pine and 
spruce trees. In fact, they are inclined to make themselves generally 
obnoxious to the little bark pests. 
It would seem that all of the conditions necessary for the imported 
Clerid to multiply and become an efficient protector of our pine forests 
from future destructive invasions of bark beetles are most favorable. 
Dendroctonus frontalis, evidently the most destructive enemy of our 
pine forests, has, from some cause, been reduced far beyond its destruc- 
tive powers. Other species which have depended upon it for the 
primary attack are, it would appear, somewhat demoralized on account 
of the disappearance of their benefactor. The large amount of felled 
timber found in the several lumbering regions will probably attract 
the larger portion of other threatening bark beetles away from the 
green trees, and by the time Dendroctonus frontalis can again marshal 
sufficient forces to successfully attack and kill the trees, they will, it is 
hoped, be met with a force of enemies led by the European Bark-beetle 
Destroyer, which will successfully repel them and thus save our forests 
in the future from destructive invasions of bark beetles. 
Mr. Smith, in discussing this paper, said that he thought the experi- 
ment entered upon in West Virginia well conceived, but thought that 
parasites did not greatly benefit the farmer. Mr. Hopkins, in reply, 
stated that it required enormous numbers of the Scolytids to kill the pine 
trees, and that his idea was to get some means of reducing the numbers 
of the beetles and not to completely exterminate them. That parasites 
