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were scarcely at all yellowed, but were covered with dead and dry 
patches or spots, sometimes including almost the entire leaf, which 
seemed to be not due directly to the extraction of the plant juices by 
the insects, but rather to the sun-scalding resulting from the collection 
on the leaves, in large drops or in masses, of the liquid honeydew. This 
gave an appearance which might easily be mistaken for the result 
of some fungus attack, and in fact Mr. Emory supposed at first that 
this was the nature of the trouble, andhadhadthe matter investigated 
by Mr. Waite, of the Division of Vegetable Pathology. The orchard 
was for the most part of dwarf trees and was arranged in plots, rather 
thickly planted, and covering an area of upward of 100 acres. The 
Psylla was distributed over this entire tract, but was much more abun- 
dant in the plots of older trees. The young orchard, perhaps amount- 
ing to one-third of the entire tract, was in vigorous condition and had 
not been seriously affected. The old Duchess orchard seemed to have 
suffered the most. On these trees the adults were very numerous, 
frequently 15 or 20 resting along the midrib of a single leaf. They 
were depositing their eggs along the midrib on the upper surface, and 
also thickly along the seriated margin of the leaf. I saw no eggs in 
any amount on any other part of the leaf. At the time of my second 
visit. Jul}' 31 to August 3, the eggs were much more numerous and 
had been frequently deposited in small clusters, 5 to 8 together, along 
the midrib and at the margin of the leaves. Scarcely any of the 
eggs at this time had hatched, at least not more than 2 or 3 per cent, 
and the adults were still almost as numerous as ever and busily ovipos- 
iting. 
THE PSYLLA IN THE ORCHARD OF C. C. BROWN. 
The presence of this pest in the orchard of Capt. Emory is not the 
first instance of its occurrence in Maryland. The pear orchard of Mr. 
C. C. Brown, of Pomona, Md., about eight miles south of Capt. Emory's 
place, was also very badly infested, over a limited tract, in the summer 
of 1891. The insect appeared during that year on pear trees next to 
and in the vicinity of the house, and its presence was first noticed from 
the fact that clothing put out to dry near the pear trees was covered 
with the honeydew secretion. Examination showed that it was con- 
fined to an area of 3 or 4 acres, which, however, was so thickly infested 
that the leaves and fruit fell and the trees were so stunted and injured 
that they have not since been in bearing condition until the present 
year, when they have set a fairly good crop. Curiously enough, how- 
ever, in this instance the Psylla disappeared entirely after the first 
year and has not again put in an appearance in this orchard. I vis- 
ited the orchard on August 1 and examined it very carefully, but failed 
to find the least trace of the insect. Thorough search in other pear 
orchards between and in the neighborhood of the two referred to failed 
fo >liow any indication of the Psylla in any of them. 
