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noticed here at this time may be readily distinguished from a simi- 
lar deformity, apparently occasioned by a failure of fertilization. 
Instances of this latter injury were common at Normal about the 
first of June, where the Crescent and other varieties maturing but 
little pollen were badly buttoned; but here, invariably, the seeds, 
or achenia, of the shrunken area were blighted and empty, even 
although the shells had grown to the ordinary, size. 
The weather at Cobden, I was informed, had been extraordinarily 
dry and cool for about three weeks, until the 14th of the month 
being thus especially unfavorable to the growth of the plants and 
the maturing of the berry. This drouth likewise probably stimulated 
the development and multiplication of the insects themselves. At 
Centralia, however, the weather had been entirely favorable through- 
out the season, but the injury in question was found equally pre- 
valent there. 
This buttoning had first been noticed by Mr. Earle, in the first part 
of May, but had greatly increased in gravity within the few days pre- 
ceding my visit. The insects had first attracted his attention on 
the 12th of the month, although he had no doubt that they had been 
present for some days in scarcely inferior numbers. 
I found in all my comparisons of different fields with each other, 
and especially of variety with variety, a remarkable difference in 
the number of the insects, according to the variety of plant in cul- 
tivation, some kinds containing two or three times as many of the 
bugs as others. In the Crescent, for example, except in a single 
instance, at Villa Ridge, but few were found; while in the Mount 
Vernon and Bidwell they were excessively abundant. In one field 
upon Mr. Earle’s farm, where Miner’s Prolific and Crescents had 
been planted in alternate rows for the purpose of securing a fertili- 
zation of the latter, a careful search and count of adjoiming rows 
of the two varieties, showed that the insects were two and a half 
times as num+-rous in the Miner’s Prolific as in the Crescent; while 
in patches of the Bidwell and Mount Vernon immediately adjoining 
the above, they were at least three times as numerous as in the 
Miner’s Prolific. The Sharpless was also badly infested, while in 
the Downings, Wilsons, and ‘‘No. 2,” the plant bugs were only 
moderately abundant. 
The fact was repeatedly noticed that in those fields and varieties 
where relatively few were found, the ratio of adults was much greater 
than in situations where the insect was more abundant,—clear evi- 
dence that the difference between the numbers infesting these various 
fields had been greater earlier than it was at the period of my visit, 
the larger ratio of adults in some fields being clearly due to the 
fact that the matured individuals scattered from the field where they 
developed as soon as they acquired wings. 
Only one or two cases afforded an opportunity to inquire into the 
effect of a mulch of straw or leaves upon the ground; but these 
tended to show that this had no especial effect upon the abundance 
of the insect. The Bidwells, Crescents and Miner’s Prolific, already 
mentioned, belonging to Mr. Earle, in which the numbers of the 
insects varied greatly according to variety, had all received precisely 
the same treatment as to mulching; while the field of Mt. Vernons, 
