86 DIPTERA 
44. Eyes of male separated ; discal cell of female often. more or. less * 
broadened ; hairs of abdomen mostly shite or brown; dorso- 
centrals usually weak, hair-like and in several rows; legs 
with few bristles, those of female not feathered . . . . . Subgenus MrcacvrTARus, Bigot. 
Eyes of male contiguous; discal cell of female not widened ; 
dorsocentrals usually im ome or two rows, if short and in 
several vows then. the thorax is shining black; legs of female 
SENE TEASE T . s ow DAR SS 
45. Pygidium vesiculate above or broadly deformed, the seventh 
tergile usually set in. the wide sixth, often with wo prongs 
below and with two bunches of yellow brisiles on last sternite; 
thorax usually opaque, dorsocentrals hair-like, multiseriate, 
scutellars numerous ; wiugs of female usually rather broadened ' 
and brown; hind femora rarely selose below... . . . Subgenus DasvRHAMPHOMYL, Frey. 
Pygidium of other form, usually small, half-open, with short 
lhick penis; hind femora of both sexes usually more or less 
bristly below |... . . . . . . . . . . . . Subgenus RHAuPHouyra, Meigen, s. str. 
Subgenus PagAnHAMPHOMYIA, Frey. 
I. GeENus PARATHALASSIUS, Mik 
Parathalassius, Mik. Wien. Ent. Zeit. Vol. 1o, p. 217 (1891); Coquillett, Proc. Ent. Soc. Wash. 
Vol. 5, p. 255, 260 (1903); Melander, Williston N. Amer. Dipt. p. 224 (1908); Becker, Wien. 
Ent. Zeit. Vol. 28, p. 25-27 (1909); Kertész, Cat. Dipt. Vol. 6, p. 101 (1909). 
Characters, — Small robust silvery gray pruinose species with white bristles, Head longer 
than broad, occiput rather flattened, eyes of both sexes widely separated on the front, approaching just 
beneath the antennz so as there to narrow the face, more in the male and less in the female, and then 
again diverging below, anterior and central facets large, the uppermost facets minute, eyes strongly 
pubescent, especially below, where in the male the hairs give a glistening sheen to the eyes; face concave 
above, convex below, the oral margin at the lowest level of the eyes and not excised, fringed especially 
in the male with white hairs; basal joints of the antenna fused and nearly bare, the third joint pyriform, 
with a slender two-jointed arista which is as long as the antenna itself; proboscis very short, tubular and 
thick, not or scarcely projecting; ocelli widely separated, not elevated, ocellar bristles distant and diver- 
ging, a pair of strong converging fronto-orbitals ; bristles of the upper occiput moderately strong, below 
a mystax of coarse white hairs present. "Thorax stout, not highly arched, five or six strong dorsocentrals, 
one posthumeral, several supraalar, two or more scutellars, the middle pair distant; pleurze uniformly 
and densely pruinose and devoid of hairs. Abdomen thick and short, densely pruinose, its hairs coarse, 
only moderately long; epipygium very large, tumid, globose, twisted to the right, its under parts coarse 
and complicated ; fifth segment terminating the abdomen of the female, the apical segments retracted. 
Legs simple, pruinose, the femora more or less ciliate, middle tibize with an apical bristle. Wings 
narrow, with parallel sides, costa continuing around the entire wing, several basal bristles and costal 
setulze present, third vein simple, discal cell narrow and long, its basal crossvein abortive, anal crossvein 
straight and perpendicular, anal vein angulate at the crossvein and strong halfway to the margin, anal 
angle broadly rounded, no alula, the alular hairs moderately long; calypteres with straight margin. 
Type species : P. Blasigii, Mik, the original species. Judged by the course of the anal cross- 
vein this genus should be located in the Ocydromiinz, but as all the other characters clearly point to 
