The Collaborative International Dictionary
Lecanium pyri
Bark louse \Bark" louse`\ (Zo["o]l.) An insect of the family Coccid[ae], which infests the bark of trees and vines.
Note: The wingless females assume the shape of scales. The bark louse of the vine is Pulvinaria innumerabilis; that of the pear is Lecanium pyri. See Orange scale.