ART. 10 GALL-INHABITING CYNIPID WASPS WELD 71 



Sheridan, 111.: Ironton, Mo.; Falls Church and Rosslyn, Va.; Plum- 

 mer Island, Md. ; Washington, D. C. Barlow collected them at 

 Cadet, Mo., Miss Howe at Ithaca and Crosby at Farniingdale, X. Y. 

 On Q. hicolor common at Wilmette and Evanston, 111., where flies 

 emerged June 15-23, 1909. and June 10-16, 1912. At Washington 

 galls contained pupae May C, 1914. These galls have also been 

 seen on Q. viacrocarpa at Winnetka, 111. and on Q. steUata at Ross- 

 lyn, Va. 



ANDRICUS CHRYSOBALANI, new species 



Fenuile. — Red, distal part of antenna and posterior portion of 

 abdomen infuscated. Head broad as thorax, broadened behind eyes, 

 malar space five-eighths eye with fan striae, antennae 13-segniented, 

 lengths as (scape) 12(width 5) : 7(4) : 10 : 12 : 11 : 11 : 10: 9 : 8 : 8 :- 

 8:7.5:14(4.5). Sides of pronotum coriaceous, mesoscutum finely 

 rugose, parapsidal grooves percurrent, faint median line extending 

 to parallel lines. Disk coarsely rugose except for a finely rugose 

 area behind the pits. Carinae on propodeum parallel. Hind tarsus 

 shorter than tibia, its metatarsus as long as 2—4 united, claws with 

 stout tooth. Fore wing hyaline, short pubescent, margin not ciliate, 

 veins very pale, areolet faint and reaching one-sixth way to basal, 

 cubitus scarcely visible. Abdomen as long as head and thorax, 

 length to height to width as 23 : 23 : 14, second tergite occupying 

 two-thirds, ventral valves oblique, ventral spine short, slightly 

 hairy. Using width of head as a base the length of mesonotum ratio 

 is 1.3, antenna 2.5, wing 3.7, ovipositor 2.1. Range in length, 1.8-2.4 

 mm. Average of 33, 2.1 mm. 



Male. — Similar to female but head darker, antennae 15-segmented, 

 third slightly excavated and bent, the short pubescence on wing 

 darker and veins more distinct, abdomen shorter than thorax, claws 

 simple. Range in length, 1.6-2.0 mm. Average of 4, 1.8 mm. 



r?/;?e.— Cat. No. 27209, U.S.N.M. Type female, allotype, one male 

 and 11 female para types. Paratypes in American Museum, Field, 

 Stanford, Harvard, Philadelphia Academy, and California Academy. 



Host. — Quercus cJirysolepis. 



Gall (fig. 14). — Consists of a larval cell horizontally placed inside 

 of and in very base of young acorns in midsummer. Affected acorns 

 are those of the current season whose growth has been so retarded 

 that they are undersized (10-18 mm.), often lopsided, v>'ith the cup 

 more or less distorted. The cotyledons do not develop inside. The 

 exit hole is in the top of the acorn and the cup is not involved. 



Habitat. — The type locality is Kyburz, Eldorado County, Calif., 

 where infected acorns of the current season were collected August 4, 

 1922. Some already contained fresh exit holes and one gall of those 

 cut open contained a pupa. Flies emerged from the galls on August 



