REPORT OF THE STATE ENTOMOLOGIST 1901 TAT 
are a little less than j; of an inch in diameter, nearly circular 
in outline, strongly convex and varying in color from a light 
golden yellow to adark brown. They are usually bordered by a 
line of white excreted matter, and on badly infested twigs the 
edges of one scale may overlap those of another. The removal 
of a scale will reveal a distinct hollow in the bark, showing that 
Fig. 18 Pseudococcus aceris: aadult females on leat; b young female and males on bark. 
Natural size. (After Howard, Insect life. 1894. 7: 235) 
the growing bark has developed around rather than under the 
insect. This scale insect has been quite injurious in earlier 
years to English oaks at Geneva N. Y., apparently doing more 
harm to large trees. | 
The young of this scale insect begin to appear in the latitude 
of Washington D. C. about the first of May, but Prof. Lowe, in 
his report for the year 1895, states that at Geneva N. Y. the 
