20 
DIPTERA 
apex; 2+14 jointed, the first joint as bioad as long, the second twice as broad as long, and the others 
twice as long as broad; proboscis ver}- robust, shorter than the height of the head; palpi four jointed, 
eyes emarginate opposite the antenna?; ocelli wanting. Abdomen slender, more than three times as long 
as the thorax (PI, 3, Fig. I 9, diagrammatic). 
Type species : H. Johnsoiii, Coquillett. 
Geographical distribution of species : 
I. H. Johnsoni, Coquillett, Ent. News, Vol. 11, p. 429(1900). N. J., United States. 
10. Genus APEMON, nov. gen. 
Characters. — Resembles Platyuia but differs in having a distinct, though delicate, fold-like 
basal portion of the media arising near the base of the wing, and in having no setae, but only fine hairs 
upon head, thorax, coxas and femora. The setjE of the abdomen, tibiae and tarsi very small and incon- 
spicuous. Antennae 2-I-14 jointed, flagellar joints cylindrical, under twenty diameter magnification only 
indistinctly pilose; ocelli large, arranged in a transverse line on the broad front, middle one only slightly 
smaller than the others; eyes pilose; palpi incurved, rather long, basal joint very small, second broad, 
about as long as broad, third joint about half as broad but twice as long as the second, fourth slender, 
about five times as long as broad; proboscis short. Thorax moderately arched, dorsum and scutellum 
provided only with hairs, those over the base of the wing and on the scutellum rather longer, pleura 
and metathorax nearly bare. Abdomen depressed, flattened, broadened apically, segments finely setulose, 
particularly on basal portion; male genitalia small, simple, consisting primarily of two incurved lateral 
lubes, toothed at the apex. Tegs moderately long; coxas long, these and the femora short haired, setulae 
of the tibiae less than one-fourth the diameter of tibia in length, spurs strong ; fore metatarsus shorter than 
the tibia; all tarsi finely setulose, claws with teeth near the base of each; empodium conspicuous. 
Wings (PI. 3, Fig. I 7) resembling those of Platyura; media arises near the base of the wing, its first 
section is delicate and fold-like; Rz+i joints Rj near its apex; anal vein prominent, produced to the 
Wing margin. 
Type species : A. pectoralis, Coquillett. 
Geographical distribution of species : 
1. A. gracilis, Williston, Kans. Univ. Ouart.Vol. 2, p. 60 (Platyura) (i8g3). Western United States. 
2. A. maiidae, Coquillett, Canad. Ent. Vol. 27, p. 199 (Plalyiira) (iSgS), Western United States. 
3. A. pectoralis, Coquillett, ibidem (Platyura) (iSgS). Western United States. 
4. A. pitlchra, Williston, Kans. Univ. Quart. Vol. 2, \). Scj (Platyura) (iSg3). Western United States. 
I I. Genus PLATYURA, Meigen 
Platyura. Meigen, Illiger's Mag. Vol. 2, p. 264 (i8o3); Klass. Vol. 1, p. loi (1804). 
Zelmira. Meigen, Nouv. Class. Mouches a deux Ailes, p. 16 (iSoo) (without type). 
Orfelia. A. Costa, II Giambatt. Vico. Vol. 2, p. 448 (1857). 
Characters. — Head small, transversely oval, flattened in front; eyes oval, slightly emarginate 
at the base of the antennae; ocelli three, unequal, closely approximated in a flat triangle on the broad 
front, the median ocellus smallest; palpi incurved, four jointed, the first joint small, the second oval, 
equal or shorter than the third, third and fourth cylindrical, the fourth longest; antennae equal or longer 
