138 



STATE POMOLOGICAL SOCIETY 



nursery stock and spreads through winged forms of the insect 

 and the agency of birds whicli carry the young hce on their 

 feet. It is not uncommon to find apple trees as badly infected 



Howard, Kntoniological Division, U. S. Dept. of Agriculture, 1894. 



THE OYSTER-SHELL BARK LOUSE. {TrytUaspls pomorum.) 



a, female scale from below, showing eggs; 6, same from aliove— greatly en- 

 larged; c, female scales; rf, male scale— enlarged (original) ; e, male scales on twig 

 — natural size. 



as the branch I show you. This species is fully considered and 

 illustrated in the report of the Maine Experiment Station 1888 

 p. 157. We are not a^vare that much efifort is made to check 

 it. It does not usually kill the trees, but must be a great drain 

 upon them dwarfing the shoots and fruit. 



THE ELiM-TREE llAKK-LOUSE. 



Lccaiiiiun Caryac, Fitch var. Caiiadciisc, Cockerell. This is 

 a bark louse of a mahogany brown color and hemispherical 

 shape. It is very abundant upon elm trees all over the State and 

 must do much damage. The branches in spring are sometimes 



