624 ' NEW YORK STATE MUSEUM 



longitudinal grooves, convereinof towards the scutellum and a short grroove 

 on each side of the middle one, reaching halfway from the collar to the 

 scutellum, also a short, shallow groove or depression over the base of the 

 wings. Scutellum with coarse, irregular pits or punctures. Legs reddish 

 brown, coxae and tips of tarsi dark brown or black. Dorsal portion of the 

 abdomen black, ventral, reddish brown, second segment has a few scattered 

 hairs beneath the wings, others (except the first) minutely punctate. Wings 

 hyaline; veins brown, rather slender; areolet small, distinct; radial area 

 not closed. Length. 15. 



Horned oak gall. Andricits cornigcriis Osten Sacken. This irregu- 

 larly rounded gall is woody with numerous hornlike protuberances through 

 which the gall flies escape. It is very hard, of the same color as the branch, 

 is from j4 to i}4 inches in diameter and contains within many larval cells. 

 It occurs on the branches of pin oak, scrub oak and black-jack oak and is 

 recorded by BeutenmuUer as being exceedingly common in the vicinity of 

 New York city. 



Oak tip gall. Andricus claviila Bass. A green or brown, club-shaped, 

 hard, woody gall with a few leaves growing from its summit, occurs at the 

 tips of white oak twigs. It is recorded by BeutenmuUer as very common 

 about New York. 



Rough bullet gall. Holcaspis diti'icoria Bass. A globular, rough gall 

 with conelike apex, occurs somewhat commonly on scrub and swamp oak. 



This gall resembles the bullet gall but may be distinguished by its 

 much rougher exterior, less globular form, flattened base, and tlie apex 

 extended into a conelike process. It occurs rather commonly on scrub oak 

 at Karner and it is stated by BeutenmuUer to be rare on swamp oak in the 

 vicinity of New York city. 



Oak bullet gall. Holcaspis globulus Fitch. Bulletlike galls in clusters 

 of two, three or more are common on the terminal twigs of white oak and 

 occur also on the post and chestnut oaks. This gall is yellow or reddish in 

 summer, turning brown with the approach of cold weather, is corky in 

 texture and contains a larva in the small central cell. 



Oak potato gall. Ncurotciuis batatiis Fitch. Large, hard, uneven galls 

 ^ inch thick and two or three times as long, somewhat resembling a potato 

 in shape, occur on white oak twigs. 



This peculiar deformity to oak twigs is abundant on the branches of 

 young trees in the vicinity of New York city. It is a hard, woody 

 growth with the surface coated with pale bluish bloom and internally it has 

 a dense corky texture with numerous larval cells. It is sometimes quite 

 injurious on account of its deforming young trees. 



Noxious oak gall. Ncuroterns noxiosns Bass. An irregularly rounded, 

 hard, woody gall resembling that of N. batatus Fitch, occurs on the 

 terminal twigs of swamp white oak. 



