LEAF-HOPPERS. lieved 
with white lines and dots, and also with two prominent black 
lines at the margins of the upper wings; the latter is of a trans- 
lucent white color, prettily marked with red lines and prominent 
black spots at the tip of wings and two black lines at the margin. 
The younger stages of both are very pale, but the insects in that 
stage are almost as active as the adult ones, though lacking, of 
course, the wings. They will dodge about in a most amusing 
way, and as they, like the adult ones, jump readily, they are 
not easily captured. Like all insects belonging to this order they 
are active and take food as soon as born, not passing through 
an inactive pupal stage like beetles and moths. They take their 
food by suction, hence the application of such stomach poisons 
as Paris green or London purple is of no avail, though it will 
kill, by contact, some of the still very tender and younger speci- 
mens, or even adult ones while they are just shedding their skins 
and are still very soft and unable to clean themselves. The only 
remedies that promise success are insecticides which kill by 
contact, as kerosene-emulsions, tobacco-extracts, insect powders, 
and others. The former, to be of any use at all, should be ap- 
plied very early in the morning, when the insects are less active 
than later in the day. A number of different insecticides were 
tried at a time, when the leaves, even at that early date, May 20, 
showed already considerable injury, being somewhat withered 
and curled, and appearing scorched and very unhealthy. 
The following experiments were made: On May 2oth a 
mixture of kerosene and water was applied with a knapsack 
sprayer having a special arrangement for mixing the two liquids 
without previously making an emulsion. This liquid was used 
in the proportion of one part of kerosene to 15 parts of water, 
and the vines were thoroughly moistened with it. During the 
spraying the leaf-hoppers rose in swarms, and many fell to the 
ground, but the greater part of these recovered and flew away 
to return in the course of half an hour. A few were rendered 
inactive and appeared paralyzed for a time, but very many of 
these recovered in less than half an hour. The mixture seemed 
to produce no permanent effect upon the insects, simply because . 
the integument of these minute beings is very smooth. To remove 
the offensive fluid the insects used their spiny hind legs very 
diligently and with success. 
