REPORT OF THE STATE ENTOMOLOGIST 1901 



747 



are a little less than r 6 of an inch in diameter, nearly circular 

 in outline, strongly convex and varying in color from a light 

 golden yellow to a dark 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: a adult females on leaf ; 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. 0. about the first of May, but Prof. Lowe, in 

 his report for the year 1895, states that at Geneva N. Y. the 



