89 
ments are: (1) That ‘ the insect is rarely injurious in two consecutive 
years,” * and (2) that the remedy consists in a “summer spraying 
with a dilute kerosene-soap emulsion.” ’ These, or similar statements, 
have appeared in every article heretofore written on this subject, and 
during the past summer I have been shown a score of letters from 
entomologists making these statements. 
Early in June of this vear I received a note from the chairman of 
the North Shore Park Commission stating that a committee of the 
Rogers Park Improvement Association had been appointed to devise 
means. for the elimination of the cottony maple scale. This com- 
mittee asked me to investigate the subject and undertake the work of 
spraying in the territory of Rogers Park—a Chicago suburb, but. 
within the city lmits. Upon investigation I found the soft or 
silver-leafed maple (Acer dasycarpum) to be the principal shade 
tree here, and every tree was covered with the white egg masses of the 
Pulvinaria. ‘These insects have been present in this territory in large 
numbers each year since 1886 at least. In 1897 a large number of 
the trees were: severely pruned, the supposition being that this would 
eliminate the scale, and the beauty of the trees was thus largely 
spoiled... The insects have been so numerous that they have cestroyed 
the lower and smaller branches and killed hundreds of trees out- 
right. The work of the Pulvinaria, together with the pruning in an 
effort to get rid of it, has caused the trees to look anything but beau- 
tiful. This same condition exists at other places around Chicago, 
especially at Evanston and Irving Park. No soft maples are now 
being planted in this territory on account of the ravages of the insect. 
During the past summer the eggs were slow in hatching, as the 
season was very backward. Up to June 25 practically no eggs were 
hatched. Two quite warm days occurred about July 10, and this 
served to bring them out. At this time the larger limbs and branches 
were fairly alive with the young going from the egg masses to the 
leaves. Persons pruning the trees at this time would get the insects 
in the hair and upon the person and clothes in the same manner as 
chicken mites. The insects were scattered to surrounding shrubs and 
flowers in varlous ways, especially by the falling of the weakened 
leaves, so that during August they were to be found on practicaily 
every shrub. 
The list of plants upon which I have found the Pulvinaria is con- 
siderably larger than heretofore given. Of course a distinction 
should be made as to what constitutes the normal food plants, or those 
upon which it occurs in both summer and winter forms and the food 
plants upon which it may have drifted for the summer. My own 
observation gives the following as the normal food plants of the 
@ Bul. 22, Div. of Enut., U. S. Dept: Agric., p. 16. b Loe. cit. 
