t)26 NEW VURK STATE MUSEUM 



Oak leaf bullet gall 



Dryoplia)ita polita Bass. 

 * 

 A small, globular gall occurs in numbers in August and Seiitembcr on both surfaces 

 of the leaves of scrub and post oak. 



This gall ranges from about I4 to 3^; inch in dianu-ter, is at first pale 

 green but sunlight changes it to red or reddish brown. It is found on the 

 foliage of young antl thrifty shoots, from one to 20 occurring on a leaf. 

 When dry the shell is very thin and brittle and contains a round larval cell 

 held in a central position by radiating branching fibers which extend to 

 the outer shell. The perfect insect becomes matured in October and 

 remains in the gall over winter. 



Oak fig gall 



Biorliiza foi't icoriiix Walsh 



Irregular reddish tinted, greenish galls occur in dense clusters along the midrib of 

 the leaves or on the stems of wiiite and scrub oaks in midsummer. 



This sjiecies is rather common, and was met with at Karner on the 



dwarf chestnut oak, O u e r c u s ]) r i n o i d e s, being ([uite abundant in lim- 



itetl localities. The galls on the young twigs and leaves are very pretty 



about the middle of August, being irregular in shape, greenish yellow and 



tinted with red. Plate 48, figure i, represents a massf of forming galls 



and shows the badly infested shoots as well as the foliage. The galls are 



foinid along the midrib on both the upper and imder surface. The old 



galls, as they appear on the dead twig are represented at [jlate 48, figure 



2. It will be seen that they constitute a very irregular mass and look 



not unlike figs closely packed around a central stem. The gall Hies emerge 



from small circular holes. This species was met with b)- Dr b'itch on 



thrifty growing white oaks, on which tree he stated it is quite abundant. 



llis iIcscri])tion of the formation of the galls is as follows: 



I he lemale pierces the Ijark with her ovipositor, and inserts a number 

 of eggs at a short distance from each other, apparently sinking them into 

 the wood beneath the bark causing a little discoloration and a spongy spot 

 runs inward from the gall to the pith of the limb. These wounds of the 

 bark heal over so that no indication of their presence can be detected with 

 a magnifying glass. A little smooth round swelling or elevation on the 

 bark soon commences above the ecre, increases in size, till at lenoth the bark 



