234 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.59. 



oxenus humilis Weld, but the larval cells are ellipsoidal, 3.25 mm. 

 long by 1.25 mm. in diameter, tying lengthwise just under the bark. 



Female. — Head wider than thorax, second segment of antenna as 

 broad as first and both flattened, abdomen longer than high, oviposi- 

 tor when dissected out one and one-third times as long as antenna. 

 Using width of head as a base, the length of mesonotum ratio is 1.3; 

 antenna, 2.0; ovipositor, 2.S; wing, 3.3. 



Habitat.— Oc&l&, Florida. Galls collected October 30, 1919. When 



cut open February 23, 1920, pupae and four transformed flies were 



found. 



Genus COMPSODRYOXENUS Ashmead. 



This genus is not closely related to Riiodites, as indicated in the 

 Tierreich key on page 299, for the hypopygium is not ploughshare- 

 shaped as in that genus. It is more closely related to Solenozoplieria 

 Ashmead and may be recognized by the use of Ashmoad's key in 

 Psyche (vol. 10, p. 155), where it is placed close to Bassettia Ashmead. 

 Only two species have been described, both from twig galls, and 

 three more are here added, also from slight twig swellings at the base 

 of young sprouts underground. As access was had to the types of 

 the described species, a key to the existing species in the genus is 

 here presented. 



1. Front wing with the normal pubescent surface and ciliate margin 3 



Front wing very short pubescent and without the normal ciliate margin 2 



2. Scutellum mostly rugose, slightly coriaceous on disk. Size 2.8-4.1 mm. Average 



3.6 mm. California viaculipennis Ashmead. 



Scutellum disk coriaceous, rugose behind and on sides. Size 2.3-3.0 mm. Average 

 2.5 mm. Arizona brunneus Ashmead. 



3. Wings clear illinoisensis Weld, p. 234. 



Wings with basal vein clouded and a more or less distinct transverse cloud or spot 



on second cross- vein and areolet 4 



4. Antennae 12-segmented, postocellar line shorter than ocellocular, interocular area 



square or higher than broad tenuis Weld, p. 235. 



Antennae 13-segmented, postocellar line longer than ocellocular, interocular area 

 at least 1.1 times as broad as high humilis Weld, p. 23G. 



32. COMPSODRYOXENUS ILLINOISENSIS, new species. 



Plate 35, fig. 28. 



Female. — Black with head, except eyes, antennae and legs brownish. 

 Head broader than thorax, widened behind eyes, coriaceous, sparsely 

 pubescent on face, axial line 0.58 of transfacial, interocular area 1.16 

 times as broad as high, malar space four-tenths length of eye and with 

 fine groove, palpi 5-and 3-segmented, antennae 13-segmented, first, 

 third, and fourth equal, 5-12 progressively shorter, last trifle more 

 than one and one-half times preceding. Pronotum coriaceous on sides. 

 Mesoscutum evenly coriaceous, only little longer than wide, parap- 

 sides faint, deeper posteriorly, lateral and anterior lines present. 

 Scutellum coriaceous on disk becoming rugose behind, with a few 



