lO 
DIPTERA 
2. Genus PAL/EOPLATYURA, Meunier 
Palaeoplatyura. Meunier, Misc. Ent. Vol. 7, p. 164, pi. 2, f. 9 (iSgg). 
Characters. — - Head depressed, flattened in front; front broad; eyes widely separated, ocelli 
large, three in number, arranged in a triangle, face slightly produced, proboscis somewhat prominent 
with fleshy lamellae, palpi four jointed, the first and second ver}' short, the fourth cylindrical and over 
twice as long as the third; antennae about as long as the head and thorax taken together, 2-(-i4-jointed, 
slightly flattened, the joints about twice as long as wide except the scapus and the terminal joint, the 
former short, the latter about three times as long as broad, pilose. Thorax highly arched, metanotum 
prominent, arched; setas of thorax short, those above the base of the wing and on the anterior margin 
and on the scutellum longer though not very conspicu(jus; those on the scutellum moderately long. 
Abdomen of the male of seven segments, depressed, cylindrical; the genitalia not prominent, consisting 
a pair of two jointed forceps, the basal joint stout, the terminal joint curved, about four times as long as 
broad, the apex toothed and densel)' ciliated on the inner side. Legs slender, the tibije a little longer 
than the femora and considerabl)' longer than the metatarsi; middle and hind tibiae with four longitudi- 
nal rows of minute setae, tibial spurs about one and one-half times as long as the diameter of the femur 
at the widest part; tarsal claws toothed, empodium veiy prominent, with clavate hairs. Wings broad, 
longer than the abdomen, with distinct anal lobe, setulae very fine, costa produced beyond the tip of 
almost reaching the tip of the wing; subcosta less than one-third the length of the wing, ending 
in the costa a little bej'ond the point where the radial sector begins ; Ri ends about two-thirds the length 
of the wing, R24-3 about as long as basal section of Rs and ends a little beyond the tip of Ri ; the 
R-M crossvein stout and very short; the media apparently arises near the base of the wing and is 
represented by a delicate vein to the crossvein, beyond which it is strong, and forks about halfway 
from the crossvein to the base of Rj^^a ; cubitus forks slight!}' proximad of the M-Cu crossvein; second 
anal strong but sometimes not quite reaching the wing margin (PI, 3, Fig. 7). Contains recent as well 
as fossil forms. 
Type species : P. macroueiira [Myceiobia), Loew. 
Geographical distribution of species : 
1. P. macroveura (Loew), Meunier, Misc. Ent. Vol. 7, p. 164 (1899) (fossilj. Baltic amber. 
2. P. aldrichii, nov, sp. (i) (recent). Western United States. 
3. Genus DITOMYIA, Winnertz 
Ditomyia. Winnertz, Stett. Ent. Zeit. Vol. 7, p. 14 (3) (1846). 
Characters. — Head spherical, flattened in front, vertex elevated; eyes hemispherical, bulging, 
in both sexes separated by the broad front; ocelli three of unequal size, the median smaller, arranged 
in a transverse line; palpi four jointed, the first very small, the second almost ovate, somewhat com- 
pressed laterall)', the third and fourth cylindrical; antennge projecting forward, slender, 2 -\- i5 jointed, 
the first basal joint cupuliform, the second annular, the flagellar joints elongate, oval or cylindrical, 
short pilose, the last joint very small; face ver}^ short, bare. Thorax ovate, strongly arched, scutellum 
r) P. aldrichii, nov. sp. — Pale brownish; legs yellow, tarsi infuscated; heid, face and antennas fuscous; mesonotum with three confluent 
darker stripes; metanotum dark brown; wing hyaline, with a taint smoky tinge. One male ; length 4 mm. Friday Harbor, Washington State. 
