208 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.59. 



and a few microscopic hairs along grooves. Scutellum rugose with 

 transverse arcuate furrow at base divided by a median ridge which 

 extends back to hind margin, faintly margined behind and over- 

 hanging the metathorax. Propodeum with two outwardly curved 

 ridges inclosing a rugose area broader than high and only half as 

 wide at top as at widest part. Spiracular areas rugose. Mesopleura 

 polished except for sparsely pubescent patches above and below. 

 Metapleura rugose with distinct oblique groove above. Legs incon- 

 spicuously pubescent, hind tarsi much shorter than tibia, second 

 segment shorter than fifth, claws simple. Wings dusky, with dis- 

 tinct brown veins all of which are margined by clouds especially 

 those forming marginal cell which has clear spot in center, areolet 

 distinct, cubitus reaching basal, surface pubescent, margin ciliate. 

 Abdomen smooth and polished, second tergite with scattered pubes- 

 cence on sides, making up over two- thirds length, ventral spine in bal- 

 sam broadened at base and hairy with acuminate apex, ovipositor when 

 dissected out only little over half length of antenna, ovaria"h eggs 

 well developed. Using width of head as a base, the length of mesono- 

 tum ratio is 1.5-1.8; antenna, 2.8; ovipositor, 1.5; wing, 4.1. 



M ale.— Similar to female in color, malar space one-eighth eye, 

 interocular area three-fourths as broad as high, antennae longer, 

 15-segmented, third longest and not excavated, rest gradually getting 

 shorter to the last which is shortest, gradually tapering toward end 

 from about fifth, 3.9-4 times width of head. Median longitudinal 

 ridge on scutellum evident only in transverse groove at base. Veins 

 of" wing not so heavily clouded as in female. 



Range in length of seven females, 4.0-4.8 mm.; average, 4.4 mm. 

 Of eight males, 3.7-4.3 mm.; average, 4 mm. 



Type— Cat. No. 22582, U. S. N. M. Type female, allotype, 3 male 

 and 3 female paratypes. 



Host. — Quercus chapmani Sargent. 



Gall. — A thin-walled, fleshy gall growing singly and sessile on 

 the side of roots which are 5-15 mm. in diameter. Galls are globular 

 or with a point at apex, 4-6 mm. in diameter and covered with a 

 very short dense pubescence, grayish if exposed or pale yellow if 

 buried in the sand. In early spring. 



Type locality. — Ocala, Florida. Collected April 17, 1914, when 

 some flies had already emerged and others were cut out of the galls 

 alive. They were not different from several males and females 

 captured on April 17 and 18 at Ocala by sweeping on Q. chapmani, 

 and these captured specimens form part of the type series. 



