166 THE OAK. 



Some of the resulting galls are discoid, such as the 

 " oak-spangles " of our woods ; others, again, are spheri- 

 cal, such as the common leaf -galls so well known in Eng- 

 land, and the so-called oak-apple; then there are the 

 "artichoke galls," produced by the partial metamor- 

 phosis of the buds of the oak in which the Cynips has 

 laid its egg, and many others. 



