Hear as the proof is thus made of some evident connection 
ween the abundance of insects in the field and the injury done 
the berries, this is rendered still more positive, by a fact already 
ided to, but not readily shown in this table, viz: that those 
is in which the injury was the least contained a larger ratio of 
dts than the others, these winged individuals having evidently 
sntly entered them from worse infested fields, so that the differ- 
es in number of bugs between injured and uninjured fields must 
r e been decidedly greater before any of the insects of this brood 
their wings, than when these collections were made. 
Infortunately my notes are not complete in this particular, but 
twenty-nine insects from fields but little injured, seventeen were 
dts (fifty-eight per cent.); while of two hundred and four collected 
3re the damage was serious, only sixty-eight were adults (tliirty- 
se per cent). I ought to say in respect to the method of these 
ervations, that I was in nearly every case accompanied by the 
rer of the fields, and that the estimate of damage was made by 
l, and entered upon my notes before the plants were searched 
insects. 
Itrong as this evidence may seem, it should have no more than 
due weight. What we have demonstrated is a decided proba- 
ty of a connection of some sort between the injury to the berries 
l the presence of the plant bugs, and a considerable probability 
,t this connection is that of effect and cause; that the injury 
iue, at least in part, to the absiraction of the sap from the berry 
the bug at a critical time in the development of the fruit. 
n inal proof of the amount of the injury due to the work of the 
ect, can only be had by experiment. For instance, two ad join- 
portions of the same field must be treated precisely alike in all 
pects, except that the plant bug shall be kept down in one, and 
! >wed free course in the other; when a comparison of the fields 
1 give us exact grounds for a conclusion. 
SUPPOSED POISONOUS EFFECT. 
before leaving this subject of the injuries to vegetation, it will be 
rth while to advert to one matter of both scientific and practical 
srest,—that of a supposed poisonous effect upon the plant due to 
punctures of this insect. 
)r. Harris says: “They principally attack the buds, terminal 
>ots, and most succulent growing parts of these and other herb- 
nus plants, puncturing them with their beaks, drawing off the 
>, and, from the effects subsequently visible, apparently poisoning 
parts attacked. These shortly afterwards withered, turned 
ck, and in a few days dried up, or curled, and remained per- 
nently stunted in their growth.” 
tiley remarks: “Its puncture seems to have a peculiarly poison- 
i effect, on which account, from its great numbers, it often 
»ves a really formidable foe. It is especially hard on young pear 
