72 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 97 
ventral surface of median lobe entirely membranous basal to the 
constriction. . 
Type.—U.S.N.M. No. 57321. 
Distribution.—Belmore Castle, August 9, 1941, male type. 
Named for Prof. Ulric Dahlgren, of Princeton University. 
DIPHOTUS DARLINGTONI, new species 
Puate 1, Figure 7; PLate 3, Figures 23, 27 
Field characters —Length 7.5, width 3.0 mm.; markedly constricted 
laterally between pronotum and elytra; elytra medium brown, disc 
dark brown, both with whité borders and markedly long pubescence. 
Male.—Pronotum length 1.8 mm., width 2.3 at half, 2.0 at base; 
bulbous; apical margin semicircular, basal margin moderately and 
evenly emarginate, hind angles about 90°; broadly bordered, except at 
base, in white; disc with dark brown irregular infuscation divided into 
lateral halves by a lighter, shallow, median sagittal groove; vestiture 
long and pale. Scutellum medium brown, lighter than elytra are at 
humeri; mesonotal plates light brown. Elytron 5.8 by 1.5 mm.; 
widest at basal third, then tapering gradually and evenly in lateral 
margin only; light brown or white (preservation poor), marked centrally 
with medium brown vitta, broad at humerus, thinning posteriorly 
and extending nearly to apex; lateral white border two-fifths elytral 
width, sutural border considerably narrower and. basally obsolete; 
vestiture long and pale. Head width 1.7 mm. Eye length 0.9 mm. 
Frons width 0.5 mm.; black and purple mottled, markedly concave; 
interocular margins subparallel. Maxillary palpi medium brown. 
Antennae 3.2 mm., dark brown, segments 6 to 8 each about twice as 
long as wide and with hairs about as long as width of segment. Ventral 
surface of thorax medium brown; legs light brown; claws light brown; 
tibial spurs as in D.dahlgreni but difficult to see. Tergites progressively 
darker from light brown (1) to dark brown (pygidium); pygidium 
damaged, but apparently ogival, broadest just before base, with 
apical margin bordered in medium brown. Sternites increasingly 
darker from light brown (2) to dark brown (7), though lighter than 
corresponding tergites; 8 and 9 light brown; all with straight hind 
margins. Aedeagus (pl. 3, fig. 23, a-c) probably white although pale 
brown in this poorly preserved specimen; somewhat similar to that of 
D. mutschleri Barber; lateral lobes slender, parallel-sided, dorso- 
ventrally flattened, horizontal, apposed to apical fourth where they 
separate laterally and accommodate apex of median lobe, then come 
together again at apices nearly to contact; median lobe completely 
ventral to lateral lobes except at apex, which is a sclerotized, laterally 
flattened vane, which projects between and slightly above the lateral 
lobes just short of their apices. 
