22 
this point I have observed them carefully and examined with partic- 
ular care the grass blades on which I have seen them established. 
On September 7, 1889, | swept grass where no other living plants 
were to be seen and collected numerous Hemiptera of a number of dif- 
ferent species, mostly Homoptera. The grass was very dry, brown, and 
in many places appearing dead, but evidently still furnishing support 
for the leaf-hoppers. There were but few other insects present, scarcely 
any that could be supposed to feed upon grass, except some grasshop- 
pers (Caloptenus femur-rubrum, species of Gidipoda, ete.). The species 
of Homoptera collected may I think be considered as unquestionably 
grass feeders. No other vegetation that could furnish them support 
had been on the ground swept for weeks, and the insects swarmed on 
every square foot. The grass commenced turning brown in patches 
long before it should be expected to, if affected only by want of rain, as 
it showed within ashort time after the lastrains, which had been quite 
regular and copious, previous to the dry period of that time, and its dry- 
ing up must have been hastened by losses due to the presence of in- 
sects. The ground was not yet dry enough so that the grass could 
have suffered from lack of moisture alone. Their presence on grass 
seems to show its effect in two ways, though for one of them it is diffi- 
cult to draw the line between the effects of leaf-hoppers and dryness. 
In one the effect of punctures shows in numerous pale and dry spots on 
the blades of grass resembling effects produced by related Homoptera 
on other plants, apple-trees, pear-trees, grape-vines, etc. Such spots 
ean not be found, however, in such numbers as would be expected if 
there were one for every puncture by the millions of these insects that 
occur in every piece of grass land. But the great bulk of the grass is 
withered or dead down to a certain point near the ground (or to the 
ground), which would naturally be the appearance if the leaf withered 
from the lower punctures to the tip, thus obliterating all punctured 
spots on the terminal portion. 
The difference between grass withering from punctures and from lack 
of moisture is perhaps not sufficiently different to furnish a very safe 
basis for deduction, but in the latter case it is naturally more gradual 
and holds for a longer time the green color of hay, so that for withered 
grass not too long exposed I believe we should be able to distinguish in 
some degree the difference between that killed by leaf-hoppers and that 
dried by excessive heat and lack of moisture in the ground. 
While this may fall short of actual demonstration, I think a careful 
study of the effects in the field will convince any one that my conclusions 
are justified by the facts and that, taking year after year, the amount ot 
injury caused by insects of various kinds is fully equal to the amount 
consumed by the stock ordinarily pastured on the sameland. It is evi- 
dent, then, that the prevention or the reduction of the insect injuries 
would add an equivalent amount to the return from such land. Instead 
of one cow requiring two acres for pasturage,pastures comparatively free 
