22 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. 
may surround the pole proximally from the spray, and the drip will drop 
off from its margin. Such an arrangement is indicated at J in Fig. 4. 
While oue person operates the pump, 
another, standing in the vehicle or 
upon the ground, directs the spray by 
the stiff part of the pipe. Thus the 
operator can not only spray higher and 
lower with convenience, but he can, to 
a great extent, move the spray from 
place to place without leaving his own 
position and without moving the ves- 
Sel of poison with the pump. 
- The hose and bamboo combination 
was conceived of, and used as the 
lightest, long, stiff tube practicable 
for these purposes, and it has answered 
admirably. A similar pole, with a 
metallic tube in its interior, with a 
nozzle, not producing the very fine 
Fic. 6.—Eddy-chamber nozzle, natural size; mist desired, and lacking the side dis- 
face view and section. 
charge, &e., was afterward learned of 
as being used in California. (See Agricultural Department Report, 
1881~-’82, p. 208.) 
By the apparatus used, when everything is prepared, a tree can be 
sprayed quickly, and a large grove is treated in a short time. It is 
equally adapted for forestry use in general, and likewise available for 
poisoning on fruit trees, when not in fruit, while the shorter style of 
extension-pipe is convenient for underspraying all kinds of low plants. 
THE BAG-WORM. 
(Thyridopteryx ephemereeformis Haw.) 
Although this species was not particularly destructive to our shade- 
trees in 1886, and in numbers greatly inferior to the Fall Web-worm 
and the Tussock-moth, yet in 1879 it was much more formidable, and 
at irregular intervals becomes a great pest where not properly dealt 
with, especially in more southern States. For the past two or three 
years it has been on the increase in special localities in Washington, 
and should be carefully looked after. 
HABITS AND NATURAL HISTORY. 
The Eggs.—During winter time the dependent sacs or bags of this 
species nay be seen hanging on the twigs of almost every kind of tree. 
If they happen to be on coniferous trees, and they are usually more 
abundant on these than on deciduous trees, they are not infrequently 
mistaken for the cones. In reality they are the coverings spun by our 
