92 DIPTERA 
Third antennal joint strongly constricted beyond its base, much 
shorter than its arista; mindle femora cf with about six bristles 
distributed along the under side, middle tibiz not callous; female 
black . 479.5 . M. svcoPHANTOR, Melander. 
5. Fourth ventral Midionf g Subsiude PENSIONIS intoa licbaiss process ; 
which bears spinous bristles; facets c all moderately small; mid- 
dle tibia &* with a subapical spur; acrostichals biseriate . . . M. 1SoMMATUS, nov. sp. (1). 
Ventral segments not thus developed, no ventral spines; upper facets 
G' larger; acrostichals quadriseriate . . . € x72 c M ERU 
6. Proboscis projecting forward; posthumerals sparse; pm Missi 
joint conical and longer than its arista; wings hyaline . . . E WU UM Et s 
Proboscis very short; posthumerals cf abundant; third antennal j joint 
suddenly attenuated beyond the base and much shorter than the 
arista; wings dark. . . : - «. M. arRATUS, Coquillett. 
7. Thorax gf velvety, abdomen g iti us SPEM hind tibi and : 
metatarsi c dilated. . . . . : - « « » M. osscunus, Coquillett. 
Thorax gf with two shining vittae; hairs ot the PEU black; legs 
netdied ..—. ./.. ... . . . .-. $ -4 27 M NUNT NNNM 
Geographical distribution. 
SusBGENUS MICROPHORUS, MACQUART 
1. M. albopilosus, Becker, Deutsche Ent. Zeitschr. 1910, 644 (1910). Corsica. 
2. M. anomalus, Meigen, Syst. Beschr. Vol. 4, p. 9 [1824] (Platybesa); Loew, N. and C. Europe 
Zeitschr. Ent. Breslau, Vol. 17, p. 43 (1864); Strobl, Mitteil. 
Naturw. Ver. Steiermark, Graz, Vol. 29, p. 92 (1892); Lundbeck, 
Dipt. Dan. Vol. 3, p. 192, f. 73, 74 (1910); Wahlgren, Ent. Tidskr. 
Vol 31, p. 78 (1910); Frey, Acta Soc. Sc. Fenn, Helsingfors, Vol. 37 
(3). p. 59 (1913). : 
erassipes, Macquart, Dipt. N. France, Vol. 3, p. 140, pl. 4, f. 1 [1827] (Micro- 
Phor); Hist. Nat Dipt. Vol. 1. p. 346, pl. 8, f. 7 (1834); Meigen, Syst. T. 
Beschr. Vol. 7, p, 78 [1838] (Trichina); Boitard, Nouv. Man, Vol. 3, 
p. 322 (1843); Walker, List Dipt Brit. Mus Vol. 3, p. 488 (1849); Ins. 
* Brit. Dipt. Vol. 1, p. 114 (1851); Schiner, Fauna Dipt. Austr. Vol. 1, 
P- 79 (1862). 
(1) Mierophorus isommatus, nov. sp. — Male. Length 2 mm. Entirely black, with a brownish tinge, 
halteres white. Eyes subcontiguous, touching along the middle of the front, the upper facets scarcely larger than the lower, 
third joint of the antennze conical, broad at the base, scarcely longer than wide, not produced as an attenuated portion, its 
sides slightly concave, arista twice as long as the third joint ; mouthparts retracted, only the tip normally exposed; ocellar 
triangle not prominent. Thoracic bristles sparse, acrostichals biseriate, about five pairs in number, about ten small dorso- 
centrals, two posthumerals, three supra-alars and four scutellars. Hairs of the abdomen short, sparse and black, fourth 
ventral segment polished, broadly emarginate in the middle and produced backward on each side as a large convex lobe 
whose inner margin is set with six stiff spine-like bristles; pygidium large and twisted, penis ending in two claws. Legs 
simple, not spinose or thickened, pubescence black, front tibize with loose extensor cilia, hind femora with a row of twelve 
bristles beneath which are not longer than the diameter of the femur, middle tibize with a short apical spur and middle 
metatarsi with a corresponding spur at tbe base. Wings dark, rather broad, stigma distinct, third vein sinuous, strongly 
diverging from the second at the tip, sections of the fourth vein proportioned 0.5 : 0.5 : 1 : 1.5, of the fifth vein equal. 
Female. Similar except for the separated eyes and the different genitalia, last three segments of the abdomen 
simple, broadly compressed, shining. 
Several specimens ; London Hill Mine, Bear Lake, British Columbia, altitude 7000 feet, July 21, 1903, collected by 
J. W. Cockle, Type in the U, S, National Museum. 
