IRambles witf3 nature Students 



Early in June this glossy black fly lays its eggs 

 in young briar-shoots ; the presence of these eggs 



interrupts the flow of the 

 sap, and woody tissue begins 

 to form around the eggs. 



If we take a gall of this 

 kind in an early stage of 

 growth and cut it in half, 

 we shall find several little 

 cells, each containing a small 

 white grub. These larva; 

 continue to grow to their 

 full size, and then remain 

 quiescent until the following 

 spring, when they change 

 to chrysalides. The perfect 

 fly emerges when the days 

 become warm and sunny. 



The oak tree is victimised by gall-flies innumerable. 

 They lay their eggs in its leaves, branches, flowers, 

 and roots, no part of the tree being exempt from 

 their attacks. 



WILD-ROSE GALL. 



OAK-LEAF GALLS. 



Mr. Stephens, a great authority upon insects, 

 says that there are nearly two thousand species of 

 insects which prey upon the oak tree, either as 



