LEAFHOPPERS AFFECTING CEREALS, GRASSES. AND 
FORAGE CROPS. 
INTRODUCTION. 
‘The question of the economic relation of the leafhoppers (Jassoidea) 
to the various cereal and forage crops has received some consider- 
ation, but, in the opinion of those most familiar with these insects, 
much less attention than their importance merits. 
Several factors contribute to this neglect. One is that the work of 
these insects is so insidious, and its results, except where the insects 
occur in unusual numbers, so difficult to appreciate by ordinary 
observation that it is very likely to pass unnoticed. 
Another is that the injury caused by these insects is very commonly 
charged to other agencies, either other insects, parasitic fungi, 
drought, or possibly even frost, because in many instances the insect 
itself escapes notice. 
Again there are frequently so many species involved in the injury 
that there has been a tendency, even among entomologists, to con- 
sign them all to a limbo of undetermined species, with their habits, 
life histories, and food relations unknown. 
The majority of the species are not only very inconspicuous, often. 
protected by close resemblance to the objects around them, but they 
are very active, jump quickly when disturbed, are caught with dif_i- 
culty except in a close-meshed net, and when in flight may be very 
readily taken for other insects except by a specially practiced eye. 
Among many farmers they will pass as the ‘‘fly,” which usually 
means the Hessian fly, and in recent years they have been very com- 
monly called the ‘‘green bug,” by mistaken reference to the Toxop- 
tera, which has had such general notice in the daily press. In some 
localities, notably in the northwestern wheat-growing section, the term 
‘Coreen bug’? has apparently been used very commonly for leaf- 
hoppers in the absence of the real Toxoptera. 
Under these conditions it is evident that a thorough survey of the 
situation, an investigation for a number of crops and for all parts of 
the country to determine the economic status of the group, is desirable. 
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