CHECKS UPON INCREASE OF USEFUL BIRDS. 365 
before their eyes were opened, and while they were still 
taking their mother’s milk, and could never have tasted 
birds or eggs. They were afterwards given to Mr. C. Allan 
Lyford, and reared in a cage at Worcester. One day, when 
they were well grown, one was given its liberty. The first 
thing it did was to climb an apple tree, go to a Robin’s 
nest, and begin eating out the brains of a young bird. How- 
ever, its eagerness for fresh meat may have been caused by 
a lack of animal food in its cage diet. This habit of killing 
young birds has been reported from several counties in the 
State, and must be widespread. Squirrels are quite car- 
nivorous. When meat is put up on trees for birds, squirrels 
frequently come and eat it; also, they are destructive to 
apples, pears, cherries, strawberries, and sometimes even to 
grapes, and they dig up seed corn in planting time; but 
they have two good habits, — they plant trees and they eat 
insects. Once in summer, when there were no nuts, acorns, 
or buds for squirrels to eat, I saw a gray squirrel in the 
woods go over a black oak about fifty feet in height, search- 
ing systematically, branch by branch, with its nose close to 
the bark, and apparently catching about all the insects rest- 
ing there. It went toa brown-tail moth web, and spent some 
time there. I distinctly saw one caterpillar in its mouth. 
The tree had been considerably infested by leaf hoppers and 
caterpillars. As it had a small top, and could easily be ex- 
amined, I climbed and inspected it after the squirrel had 
gone. My search occupied about halfan hour. The smooth, 
clean bark formed a dark, glossy background, on which in- 
sects could plainly be seen, and the foliage was thin, and 
not hard to examine; but I could find only about a dozen 
insects, and no brown-tail caterpillars. Since then I have 
observed other similar cases. It is not so widely known that 
squirrels eat insects as that they rob birds’ nests. Possibly 
their virtues may balance their faults ; but we shall never be 
able to determine their economic position until a thorough 
study of their food habits can be made. 
