MAINE AGRICULTURAL EXPERIMENT STATION. I91O. 329 



b. SCALE INSECTS AND PLANT-LICE. 



I. Oyster-Shell Scale. 



{Lepidosaphes ulmi.) 



This scale, which resembles an elongate oyster shell in shape 

 (fig. 3, 6) has long been known in this country, though believed 

 to be a native of Europe. It is widely distributed and is ex- 

 ceedingly abundant in Maine. Besides seriously injuring apple 

 trees, the twigs of which often densely covered by them, they 

 are found on the pear, plum, currant, dogwood, elm, maple and 

 a number of other trees and shrubs. 



Fig. 3. Oyster-shell Scale, a, female scale from below, showing eggs ; 

 b, same from above greatly enlarged ; d, male scale enlarged ; c, female 

 scales on twig, natural size, e, male scales natural size. (From year 

 book, 1894 U. S. Dept. Agr.) 



In June the eggs hatch, the active young appearing as small 

 v.hite specks which soon attach themselves to new shoots by 

 their beaks. The scale then begins to form, gradually increas- 

 ing in size. The scale of the female (fig. 3, a, h, c) is less than 

 one-eighth of an inch long, narrow, usually curved when not 

 crowded, (fig. 3, c) and nearly the same color as the bark upon 

 which it is found. The scale of the male (fig. 3, d) is much 



