68 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. 
It is very questionable whether the whitewash will destroy its eggs, but 
there is every reason to believe that the friction of the brush and the 
disengaging of many of the cocoons will cause the destruction of a 
certain number. On our larger trees the greater number of these 
cocoons are never reached by such whitewashing, because they are upon 
the higher limbs. The Web-worm cannot ve affected by the practice, 
as the hibernating chrysalids and cocoons are not found upon the 
trunks. As against these negative results of whitewashing, however, 
we must put the injurious results that follow indirectly ; because a great 
many of the enemies of the defoliators are destroyed by whitewashing. 
This is particularly the case with the egg-masses of spiders and many 
of the softer and more delicate cocoons of parasites. 
BIRDS: THE ENGLISH SPARROW. 
All four of these insects have a certain immunity from the attacks 
of birds: No. 1 by virtue of an offensive odor; No. 2 by the protection 
of its bag; Nos. 5 and 4 by the protection afforded by the hairs of the 
caterpillars, which are also mixed into their cocoons. A few native 
birds we have seen occasionally feed upon Nos. 3 and 4, but the En- 
glish sparrow, to which, being emphatically a city bird, we should look 
for help, has never been known to attack any of them. In fact, we 
noticed and announced many years ago that in some of the northern 
cities (as Boston and Philadelphia) the increase of the Orgyia was 
indirectly a result of the increase of the English sparrow, which feeds 
in the breeding season upon smooth worms less harmful to our trees, 
and thus gives better opportunity for the rejected Orgyia to increase, 
a result still further promoted by the habit of driving away the native 
birds which the English sparrow is known to have. Thesame reasoning 
will hold true in respect of the Web-worm; and, putting all sentiment 
aside, we may safely aver that this bird is an impediment rather than 
an aid in preserving our trees from their worst insect defoliators. ‘There 
is every reason to believe that the Bag-worm is carried, when young, 
from tree to tree upon the claws and legs of the bird, and its dissemina- 
tion is thus aided and its destruction rendered more difficult ; while the 
yellow suspended cocoons of the Meteorus hyphantrie (the most im- 
portant of the parasites of the Web-worm) are sought by the sparrow, 
probably being mistaken for grains of wheat. 
While our feathered friends, owing to the sparrow’s pugnacity. are 
now things of the past, and can only be seen in the spring when they 
pass through the cities in their migrations to more peaceable nesting 
places, yet something might be done to encourage their stay. Nesting 
places might be provided for them not alone by bird boxes, which, good 
in themselves, are at once oceupied by the English sparrow; they 
must be afforded safer and natural quarters. This has been success- 
fully achieved in portions of Europe and by the following very simple 
