A Study on the Life History of Kerria chinensis and Its Encrustation Phenslogy

Like other lac insects,Kerria chinensis Mahd.grows in its encrustation,therefore, it is difficult from its surface to observe its morphology characteristics of each in-star. In this paper relation between each instar and the related lac-excreting morphology andthe days which it needed in its winter and summer generation are depicted through schematicrepresentation. From the scheme,its life history, life cycle,changes and relation during itsgrowing period can be seen. At the same time characteristics of each stadium are indexedthrough index table,It is convenient to use this index table in scientific research and lac production.