386 HENRY SniMER, M. D. 



A SUMMERS STUDY OF HICKORY GALLS, 

 with descriptions of supposed new insects bred therefrom. 



BY HENRY SIIIMER, M. D. 



Having observed, in the early part of June 1868, countless numbers 

 of galls on the varieties of Hickory trees in the vicinity of Mt. Carroll, 

 Ills., I was induced to make a careful study of them with a view of 

 settling in my mind, as far as possible, their true relationship. Deem- ' 

 ing the results attained thereby sufficiently important to science, I here- 

 with present them to the entomological public. 



Sijnoptical Tahle of Galls. 



1. Galls opening with an elongated slit; containing translucent, whitish 

 eggs Nos.l^S, 6and 12. 



2. Galls with a rounded opening in an elongate nipple-like tubs : 



a. — Containing translucent, whitish eggs Nos. 2, 4, 5, 7,9 and 11. 



b. — Containing yellow eggs Kos. 8 and 10. 



Galla on the Shell-hark HicJcori/ (^Car)ja, alba). 



No. 1. — Large, hemispherical, opening beneath, Imago, length .06 in. 



2. — Flattened, partitioned; opening above and beneath " " .06 in. 



3. — Large, nut-like; on leaf-stem " " .085 in. 



4. — Flat; opening beneath, " " .06 in. 



5. — Like No. 1, except that the lower part. is conical, ''' " .055 in. 



Galls on the Bitter-nut Ilickorj/ (^Oiirjja amara). 



No. 6. — Very large ; opening beneath Imago, length .08 in. 



7. — Small; opening beneath, round, " " .045 in. 



S.— Small, leathery; opening beneath, winged imago unknown. 

 !). — Medium; opening beneath; a dimpled depression above, 



Imago, length .06 in. 



10. — Large, leathery ; opening beneath " " .07 in. 



11.— Flat, almost like No. 4 but very thick " " .045 in. 



12. — Spiny, pubeseent, irregular, opening baneath elongate sinuate. 



Imago length .06 in. 



Galls Oil the Shell-hark Hlchory {C. alha). 

 Gall No. 1. * — This is a large, subhemispherical gall, situate in the 

 ])arenchyma of the leaf, generally projecting above the plane of the 

 latter. Structure somewhat thick, tough and dense, the average thick- 

 ness of the walls being about .05 inch. Color pale whitish-green, much 

 paler than the leaf, the upper surface frequently tinged with red and 

 often quite purple-red. Size : diameter in the plane of the leaf, \ to 

 h inch ; vertical diameter one-half 



* The description of this and the following galls were made from specimens 

 in their most perfect state of development, and before the maturity of the insect 

 that produced them. 



