808 The Maple-Tree Bark-Louse. [ December, 
MODES OF SPREADING AND MEANS OF EXTIN- 
‘ GUISHING THE MAPLE-TREE BARK-LOUSE. 
BY EMILY A. SMITH. 
N the October number of the AMERICAN NATURALIST I gave the 
life history of Lecantum acericorticts Fitch, and now conclude 
with the modes of spreading and the best artificial means of de- 
stroying the insect. 
The disposition of the female to remain upgn the same tree 
throughout its entire existence renders the modes of spreading 
from tree to tree incidental to outside influences. They are con- 
veyed from one locality to another by the transportation of the 
trees while the females are upon the limbs, and are so nearly the 
color of the tree itself that without a magnifier are easily over- 
looked. The waxy mass exuded by the female in which she 
deposits her eggs, contains a sweet substance which is much 
sought after by various species of flies and wasps. When the 
young insect emerges from the egg, the tendency is to wander 
about for a time before settling upon the leaves, and the presence 
of the wasps and flies upon the tree in search of food at this time 
attracts the young lice and they attach themselves to their hairy 
legs and are thus conveyed to other trees. The wind and rain 
detach the egg-mass from the limb and convey it to otier locali- 
ties while the eggs are yet within. 
The Z. acericorticis are kept somewhat in subjection by the aid 
of the natural enemies and parasites found preying upon them; 
but when they increase beyond the power of these friends of ours 
to control them, artificial means must be resorted to. 
The experience of the past summer differs from that formerly 
known in that the insects were found upon all parts of the tree 
instead of remaining upon the lower branches as was heretofore 
supposed. They are thus made more difficult to reach. When 
the lice are first hatched they are very small and delicate. A 
wash containing an alkaline solution applied at this time is suffi- 
cient to destroy them. I found that by attaching a wire bag to 
a common sprinkling hose, filling the bag with soft soap and 
turning on the water, a soap-suds was formed which would at 
once kill the insects; the scarcity of the water system in small 
cities renders this olad impracticable, and experiments led to one 
o plan, easily attained by all, and which proved successful the past 
