Canker-worms of one or of several species often strip them of their leaves; the tent-caterpillars pitch their tents among the branches and carry on their dangerous depredations; the slug-worms, the offspring of a fly called _Selandria cerasi_, reduce the leaves to skeletons, and thus destroy them; the cherry-weevils penetrate their bark, cover their branches with warts and cause them to decay; and borers gnaw galleries in their trunks and devour the inner bark and sap-wood.'
