﻿326 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 102 



pleiiron rugose, more coarsely so anteriorly. Wing pubescent and 

 ciliate, the blotch at base of radial cell covering the areolet also. Tar- 

 sal claws toothed. Carinae on propodeum strongly bent, enclosed area 

 rugose with a short median. Abdomen about as long as thorax, lengths 

 of tergites on dorsal margin as 38 : 8, tergite II smooth on hind margin, 

 III punctate. Ventral spine pubescent, as long as hind metatarsus. 

 Using width of head as a base the length of mesonotum ratio is 1.5; 

 antenna 2.1 ; wing 3.2 ; ovipositor 2.0. Length 4.15^.8 mm. Average 

 of 10 specimens 4.58 mm. 



Male, — Similar but abdomen black. Antennae 15-segmented, the 

 third stoutest, the flagellum tapering to tip. Abdomen shorter than 

 thorax, all tergites visible on dorsal curvature. Antenna ratio 3.3. 

 Length 3.5^.0 mm. Average of 11 specimens, 3.74 mm. 



Differs from A. spongifica (Osten Sacken) , whose tergite II is punc- 

 tate posteriorly. 



Typea. — IT.S.N.M. No. 60113 : Type female, allotype, and three para- 

 types. Paratypes also in A.ISI.N.H., C.M.N.H.. A.N.S.P., C.A.S., and 

 M.C.Z. 



Host. — Quercus palustris. 



Gall (pi. 16, fig. 4, a). — A bud gaU in June produced from weak 

 lateral buds on previous year's growth of saplings 1 to 3 feet high, 

 on sprouts from stumps and on lower limbs of small trees, occasionally 

 from dormant buds on main trunk of trees. In good light, deep green 

 with white spots at attachment of radiating fibers inside; in deep 

 shade, more or less etiolated. Globular, firm, fleshy, bare, up to 18 

 mm. in diameter, not deciduous. Wall 1 mm. thick. Central cell rela- 

 tively large, supported by many coarse, branching, radiating fibers. 

 Larval cell 6 mm. by 3.2 mm. and its wall 1.5 mm. thick with big cells 

 at base of the radiating fibers. Exit hole 2.2 mm. in diameter made 

 while gall is still green. After the emergence of the maker the gall 

 turns brown and becomes wrinkled. Many undersized galls are para- 

 sitized. Out of more than 200 galls collected only 20 makers emerged. 



Habitat. — The type series of galls was collected at East Falls 

 Church, Va. June 26, 1948. Adults emerged June 28, 30, July 2, 4, 

 1948. None of these galls was seen at this place in 1949, in 1950, or 

 in 1951. Galls had been seen at Rosslyn and Lucketts, Va., Washing- 

 ton, D. C, and Lanham, Md. 



AGAMIC GENERATION ? 



In early September 1948 approximately 65 bud galls were collected 

 on the ground under a large pin oak tree only a few feet from where 

 galls of A. globus herein described were taken the previous June. 

 Similar galls had not been seen here before — circumstantial evidence 

 that it is the alternating form. It occurs in August and September at 



