﻿322 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 102 



(9) . Mesoscutum without trace of parapsidal grooves. Wing pubes- 

 cent and ciliate, second cross-vein at angle of 55 degrees with basal, 

 areolet reaching one-fourth way to basal. Claw with a weak tooth. 

 Abdomen higher than long, ovipositor often extruded. Using width 

 of the head as a base the length of niesonotum ratio is 1.17: antenna 

 1.8; wing 4.3; ovipositor 3.3. Range in length of 100 measured speci- 

 mens 1.75-2.05 mm. Average 1,91 mm. 



Types.— U.S.'NM. No. 60109 : Type and 20 paratypes. Paratypes 

 also in A.M.N.H., C.M.N.H., A.N.S.P., C.A.S., M.C.Z., I.N.H.S., and 

 C.U. A gall is on each pin. 



Host. — Quercus alba. 



Gall (pi. 16, fig. 1). — Small saucer-shaped galls occurring in large 

 numbers attached by a broad base on under side of leaf in early sum- 

 mer. Individual galls measure .9-1.6 mm. in diameter by .6-7 mm. 

 high, with an elevation in center of the concave free surface, brown, 

 almost bare, dropping off when mature and leaving a scar .7 mm. in 

 diameter on the gall and a brown spot on the leaf. 



HaUtat.—Tyi^Q locality. College Park, Md. On May 24, 1948, W. H. 

 Anderson swept up a tablespoonful of the galls, which had fallen on 

 a table under a heavily infested white oak tree. These were placed 

 in a breeding cage on the ground outdoors and when examined on 

 April 1, 1949, scores of adults had emerged and many had already 

 died. 



Genus TRICHOTERAS Ashmead 



TRICHOTERAS PERFULVUM, new species 



Female. — Piceous; mandibles, parts of scutellum and legs, brown. 

 Head coriaceous, pubescent; from above transverse, as broad as 

 thorax, cheeks not broadened behind eyes; from in front almost cir- 

 cular, malar space one-third eye, without groove, antennae filiform, 

 12-segmented, lengths as (scape) 16 : 11 : 20 : 19 : 17 : 17 : 15 : 11 : 10 : 9 : 

 8 : 18. Pronotum and mesonotum somewhat shining with uniformly 

 distributed appressed hairs from prominent punctures. Mesoscutum 

 broader than long, parapsidal grooves percurrent. Scutellum lugose 

 posteriorly, with two widely separated smooth pits at base. Wing 

 pubescent and ciliate, veins brown, third abscissa of subcosta almost 

 parallel Avith second abscissa of radius, radial cell five times as long 

 as broad, areolet present. Mesopleuron largely bare, smooth, polished. 

 Tarsal claws with a strong tooth. Carinae on propodeum slightly 

 bent, area on either side pubescent. Abdomen bare except for usual 

 pubescent patches at base of tergite II, tergite II foliiform. Ventral 

 spine slender, about five times as long as broad in side view, shorter 

 than hind metatarsus. Using: width of the head as a base the length 



