54 [October 



Irregular, with numerous seed-like kernels. 



10. WLiite oak; Cynips qiterciis lanse Fitch. 

 Post oak; gall-fly unknown. 



A A. Galls more or less intimately connected with the substance of the leaf, 

 projecting generally on both its sides (except No. 17), they cannot 

 therefore be detached without carrying a portion of the leaf with 

 them. 

 On buds or very young leaves. 



Grlobular, hollow gall, with a single, whitish, cocoon-like kernel, 

 rolling freely about within the shell. 



11. Pin oak; Cj/nips qucrcus piduatrls 0. S. 

 Similar galls on other oaks. 



On the blade of the leaf. 

 With a sinole kernel. 



Globular, of the size of a hazelnut or grape, a third of the 

 sphere projecting on the upper side of the leaf and the re- 

 mainder opposite, on its underside. 



12. Red oak; Cynips nuhillpennis Harris. 



With two and three kernels. 



Rounded on both sides of the leaf. 



13. White oak; Cynips qxiercus futilin 0. S. 

 Nipple-shaped, with a reddish aureole on the underside of 



the leaf. 



14. Swamp chestnut oak; Cynlpi^ (picrcmpapWata O.S. 

 With a variable number of kernels or cells ; gall varying in size 



and form accordingly. 



Irregular, flattened gall of a cellular substance ; surface un- 

 even and microscopically hirsute. 



15. Post oak; Cynips qiiemts irrcgnlaris 0. S. 

 Irregular, small, hard gall, abruptly rising on the upperside 



of the leaf, somewhat subconical on the opposite side. 



16. Red oak; Cyiilpa quercus modesta 0. S. 



( )n the midrib of the leaf. 



Swelling of the midrib on the underside of the leaf 



17. Black-jack oak; Cynips quernis nigne. O. S. 

 Red oak; similar swelling; gall-fly unknown. 



Woody, rounded or club-shaped gall on the leaf stalk, at the or- 

 igin of the leaf, or on the midrib, near the basis of the leaf. 



18. Swamp chestnut oak; gall-fly unknown. 



