THE OAK. 



19 



stamens only are destined to wither and fall off as soon as 

 they have shed their pollen, being no longer of any use. 



FLOWER-GALLS. 



Those stalks, however, to which galls are attached, remain 

 firmly united with the tree, and grow vigorously as long- 

 as the grubs contained in them continue to feed. 



LEAF-GALLS. 



Another gall, resembling the last in form (being spheri- 

 cal), is found attached to the leaves of the Oak. These 

 vary very much in size, some ,,being as large as a marble ; 

 and each contains a single insect, which, when it arrives 

 at its perfect state, eats its way out through a great portion 

 of the solid substance of the gall. 



