SHRVICE OF BIRDS IN THE ORCHARD. 153 
cies of the caterpillars, trusting them to the care and pro- 
tection of the birds. I visited the place occasionally during 
the summer, and in the fall saw that measures were taken, 
as usual, to attract the birds. On November 12 I returned 
for the winter, and noticed no evidence of insect injury 
among the fruit trees. A small flock of Myrtle Warblers 
and some Goldfinches were very busy among the apple 
trees, and were paying particular attention to the pear trees 
near the house. I was told that they had been coming there 
for about two weeks. Realizing at once that they must be 
engaged upon those leafless trees in the suppression of some 
insect, I examined the trees casually, but at first was unable 
to find the object of their quest. One of the birds was 
watched closely. It was taking something from the lower 
sides of the twigs and the crevices between them. With a 
glass it was seen to take some very small insects that were 
hiding in these situations. Evidently the insects were no 
longer plentiful, as the birds had to search somewhat to find 
them, and the only way in which I could find a specimen 
was by driving a bird away just as it was about to attack the 
insect, and then examining the twig. Three tiny insects, 
which appeared like little cicada-shaped flies, were found 
and secured in this way. Two of these were forwarded to 
Dr. L. O. Howard, chief of the Bureau of Entomology, at 
Washington, who identified them as adults or imagoes of 
the pear tree psylla (Psylla pyrv), a pest imported into this 
country from Europe about 1832. According to Circular 
No. 7, second series, issued from Dr. Howard’s office, an 
overwhelming invasion of this insect occurred in the year 
1894 in one of the largest pear orchards in Maryland ; there 
were similar occurrences in Virginia and New Jersey. This 
insect has long been known as a pest of the pear tree. It is 
a true bug, of the order Homoptera, intermediate between 
the scale insects and the plant lice on the one hand, and the 
cicadas and larger plant bugs on the other. The Psyllide 
are commonly known as the jumping plant lice, on account 
of their vaulting ability. They are extremely prolific, having 
several broods each year. In the infested Maryland orchards 
the leaves and fruit fell, the latter before it was half grown, 
