THE CHINCH BUG. Ds 
chinch bugs by the bushel. In some of the cases cited the tar line 
was run in a zigzag course, the postholes being situated at the angles, 
and in others leader tar lines were run obliquely to the main tar line, 
one end terminating at the traphole, but both of these plans were 
afterwards regarded as unnecessary, a single straight line being 
entirely sufficient and less expensive. The numerous cases where 
these methods were put into execution with entire success and at 
small expense afford the best possible proof of their practical utility. 
If a farmer is situated near town, where refuse tin cans are dumped 
in any locality where they can be got out of the way, he can select 
the larger of these, set them in the postholes, and partly fill them 
with kerosene and water. The water, being heavier than the kero- 
sene, will sink to the bottom, leaving a stratum of kerosene on the 
surface. The chinch bugs falling into this will be forced down by 
the weight of those coming after, and thus all will be passed through 
the kerosene into the water below. This will obviate the necessity 
of frequently emptying the cans or treating their contents. It may 
also be stated that where the postholes are quite deep and enlarge 
at the bottom the bugs falling into them will perish without further 
attention. 
OTHER BARRIER METHODS. 
The late Dr. Snow, working in Kansas, followed a somewhat 
different method, and one that, under certain conditions, might be 
found superior to that used by Prof. Forbes, or the furrow and kero- 
sene method applied by the writer in Ohio. This modification 
consists in throwing up a double furrow, known among farmers as 
“back furrowing,”’ thus forming a ridge the top of which is smoothed 
and packed with a drag having a concave bottom of the form of the 
ridge to be made. Ifthe bottom of this drag is covered with zinc it 
will be found to keep bright and polished, and by this means make a 
smoother ridge. Along the top of this ridge is run a train of coal tar 
as it came from the gas works, or crude petroleum as taken from the 
oil wells. The former is more easily obtained, except in certain 
localities, and will probably be found the more practical, as it stands 
on the surface better and is not so readily washed away by rains. 
Both of these substances are, however, offensive to the bugs, and 
they will seldom attempt to cross them or even come close enough to 
touch them, but on approach will turn and run along the ridge in 
the evident hope of finding a gap through which they can pass. Post- 
holes were dug on the outside of the line, but close up to it, so that the 
bugs in passing along beside the tar line would crowd each other into 
them. Dr. Snow suggested that it is best to construct this barrier 
several weeks prior to the time when it will be needed, as then the 
tar line has but to be run along the ridge and the postholes dug, when 
