74 
development of the wire worms, the following- crop will very likely be 
seriously affected, whereas an early plowing is said to prove a very 
complete destruction to the insects and protection to the subsequent 
crop. 
The white grubs form another characteristic group of grass-feeding 
species, working under ground, often with remarkably destructive 
results. Recent studies by Forbes, Perkins, and others show that the 
most, if not all, mature in late summer and remain in the imago stage 
till spring, and it would seem, therefore, that early fall plowing should 
be serviceable here as with the Elaterida?. These are parasitized by a 
fungus described many years since by Prof. Riley, and are also attacked 
by a species of Isaria which has been studied particularly in France 
with the view of its dissemination. While there is no question as to 
the destructiveness of these parasitic fungi, the conditions of their 
spread in any given field are such as to make it doubtful whether they 
can be depended on for any extensive destruction of this pest. It has 
been proven that kerosene emulsion will destroy such larvae, but 
expense will limit this method to lawns or very valuable plats. 
Among the Hemiptera we have the common Chinch Bug as a grass- 
feeding species, and its most serious attacks are directed toward the 
annual grasses, but it seldom proves destructive in pastures or meadows. 
In the family Jassidoe we have a large number of species that are strictly 
grass-feeders and mostly abound in meadows and pastures, especially 
on land which has been for some time in grass. Their work is entirely 
above the surface of the ground and consists in punctures of the leaver 
and stems, these punctures resulting sometimes, I believe, in the so- 
called silver top of blue grass, and in all cases proving a drain upon the 
plants and, where the insects are numerous, an important loss to the 
crop. In the genera Deidrocephala and Deltocephalus, eggs are depos- 
itedintheleavesor stems, by the fall brood and remain over winter in this 
location; therefore, burning the grass, or its treatment with kerosene 
emulsion, is to be considered advantageous. Plowing will also doubt- 
less dispose of a considerable number, but if done at the time when adults 
can pass into other fields, it can not be considered as a complete method 
of extermination. There are a number of species of Cercopida? and Ful- 
goridae injurious to grasses, but for most of them only a few details of 
their habits are known. Aphides affect quite a number of grasses, 
attacking the roots and stems and leaves, and are for the most part 
difficult to attack. Such species as migrate to trees and woody plants 
for winter may possibly be treated with success, when we have more 
fully determined their habits. Thripida? occur very commonly in the 
blossoms of some grasses, and especially in clover. The extent of their 
damage, however, may be considered as problematic, and from our pres- 
ent knowledge of them there seems to be little opportunity to use any 
feasible method of treatment. 
In the order Orthoptera we meet a large number of species among 
