HORSEFLIES OF THE SUBFAMILY TABANINAE 151 
TABANUS METABOLUS McDunnough 
(Fig. 73, 4) 
Tabanus metabolus McDunnough, Canad. Ent. 54: 239, 1922; Hine, Canad. Ent. 
55: 145, 1923; Philip, Minn. Agr. Expt. Sta. Tech. Bull. 80: 111, 1931. 
Rather small, stout; blackish, with oblique, yellowish, sublateral spots on 
tergites 2 and 3; furcation with a rather distinct brown spot; prescutal lobe 
orange brown; subcallus denuded; palpus stout, pale; third antennal segment 
rather stout, with a moderate dorsal excision. 
Female.—Length 12-14 mm. Eye pilose, deep purple, with four green bands. 
Frons yellowish gray, about three times as high as width at base, considerably 
widened above; basal callus dark orange brown, small, rugose, subquadrate or 
transverse, and, if touching eyes, only at lower corners of callus; median callus 
black, flat, not very shiny, the margins ill defined and usually narrowly joined 
to basal callus; ocellar tubercle orange brown, small but well defined; subeallus 
denuded, shiny brown, rather convex. First antennal segment gray, with black 
hair; second and third orange, darkened beyond dorsal angle of third; basal 
portion of third with a prominent but blunt dorsal angle and a moderate exci- 
Ficure %73.—Antenna, front view of head, and palpus of (A) Tabanus metabolus and 
B) T. laniferus. 
sion, the annulate portion slightly shorter than width of basal portion. Clypeus 
and genae pale gray, with pale-yellowish hair. Second palpal segment creamy 
white, with black and concolorous hair, very stout at base, short, with an acute 
apex. 
Perea atin black, with slender gray stripes in usual pattern and orange-brown 
prescutal lobe. Pleura, sternum, and coxae dark gray, with a mixture of black 
and yellowish hair. Wing hyaline, the costal cell brown and a small spot at 
furcation; venation normal. Legs nearly black, the tibiae and hind tarsus 
strongly tinged with brown. 
Abdomen black; tergites 2-4 somewhat orange brown laterally, each with a 
rather large, oblique, superimposed, grayish-yellow spot sublaterally and some- 
times smaller ones on tergites posteriorly ; a median row of very small obsolete 
spots of same color; venter dark but sometimes with considerable yellowish 
brown. 
Male.—Hye densely pilose, the areas of large and smail facets scarcely differ- 
entiated. Coloration essentially as in female. 
Type.—A female in the Canadian National Collection. Allotype and 
paratypes in the Canadian National Collection; two paratypes in the 
Museum of Comparative Zoology. 
Type. locality.—Nordegg, Alberta. 
Distribution —Alaska to Labrador and south to Colorado and New 
York. April 13 (Pendleton, British Columbia) to August 16 (Mok- 
kovik, Labrador). In the United States National Museum, 17 
females, 2 males. 
TABANUS LANIFERUS McDunnough 
(Fig. 73, B) 
Tabanus laniferus McDunnough, Canad. Mnt. 54: 239-240, 1922; Philip, Canad. 
Ent. 68: 1538, 1936. 
Rather small, stout; shiny black, with very faint, if any, abdominal markings ; 
wing hyaline; some black pile on subeallus. 
Female.—Length 13-14 mm. Eye densely pilose, greenish, with three very 
slender purple bands. Frons about two and one-half times as high as width at 
