126 
sww«{ a at aa 
weeds. 
T ,™ some reason to believe that the difference in the suscepti¬ 
bility'of the different varieties was connected with the time ot theirl 
n tine forth their leaves in spring, it being a general rule as 
far as mv observations went, that those which were worst affected 
* ‘ iv^parliest to soring up after the season opened; but with 
respect to this, many more observations are necessary before a conv 
elusion can be reached. ] 
Tf w already been said that a certain connection was ap- 
narent between the number of insects occurring in any field and .tM 
amount of buttoning of the berries visible; and this is a matter of 
amount or ouuonu necessary to go considerably into 
such importance that it will pe nece»bd,iy tu k theorv 
resnect to the evidence collected, lo test tins t 
of ti e Tnsecr ong n of this well-known but hitherto unexplained 
■gjury, was the main object of my field work during the whole 
period of my stay. . . . . T • 
Evervwhere in the fields of Mr. Earle, at Anna which I visited 
T found a close correspondence between the amount of buttoning and I 
the number of bugs on the plant. I made many careful companj 
sons, first estimating and noting the extent of the! ^jury,^ and ; 
with an insect net sweeping back and forth ®' f gtroke , 
uniform a manner as possible, making a definite uum , i • 
and then counting and recording the number of plant bugs taken m 
the net. 
In a field of Mr. Finch, at Anna, I made a comparison of the 
Orescent and Sharpless varieties, the latter of which was much 
affected and the former but little. Twenty sweeps of the net m the 
Orescent gave but nine insects, five of which were winged, while the 
same number of sweeps in the Sharpless yielded thirty-two only five 
of wlfich were°wLged P The fields were adjoining and had received 
the same treatment throughout. | 
In Mr. Endicott’s field, at Villa Ridge, fifty sweeps of the net, m 
a field of “No. 2” which was badly affected, gave sixty-six bug , 
ten were adult while in the field of Crescents adjoining, 
every third row of which was “No. 2,” but little affected, fifty sweeps 
of the net gave twenty bugs, of which tweive were aduff s bon 
rows of badly damaged Sharpless near by yielded twenty-four bu s 
(of which half were adult) to twenty-five sweeps of the net. 
In a field of Crescents belonging to Mr. Davidson, at Villa Ihdse, 
(the only field of this variety seen during the trip whichi was bai y 
buttoned), fifty sweeps of the net gave eiglity-two of the insects. 
On the other hand, some Dowmngs belonging to Mr. liobir . 
which were considerably injured, gave only sixty bugs to fifty sweeps, 
and Wilsons, in which, likewise, many of the berries weie bm 
toned, gave but seventeen bugs to twenty-five strokes. I 
two latter cases it seemed clear that the injury o 'C err 
attributable, at least in part, to something else than the 
injury. 
