HORSEFLIES OF THE SUBFAMILY TABANINAE 121 
Hine (4) recognized conterminus as a valid species, separated from 
nigrovittatus by 1ts somewhat greater length, grayer mesonotum not 
tinged by yellow, and the greater extension of the large facets of the 
eye in the male, these attaining the hind margin. The writer has 
examined over 500 specimens and admits that there is some basis for 
this separation, at least with varietal status. However, there are so 
many doubtful specimens, possessing characters of both forms, that it 
does not seem advisable to separate them. The writer has seen speci- 
mens compared by Hine with the types of conterminus and simulans 
and these specimens were conspecific and collected at the same place. 
Therefore, if a varietal rank were to be given to the larger, grayer 
form, it must be known as s¢mu/ans, the older name. The type of 
Tabanus allynti Marten is probably lost and it is not clearly recog- 
nizable from the description. Certain rubbed specimens of niégro- 
vittatus come nearer to fitting the description than any other species 
the writer knows. 
This species is close to vicarius Walker, and the yellower specimens 
are often difficult to distinguish from vicarius. It is quite evident 
that nigrovittatus requires salt-marsh or brackish water in which to 
breed, whereas vécarius breeds in fresh water. 
TABANUS MULARIS Stone 
(Fig. 57, A) 
Tabanus mularis Stone, Ent. Soc. Wash. Proc. 37: 15, 1935. 
Small; mesonotum grayish green; abdomen blackish, with a pale, median, 
dorsal stripe; costal cell orange brown; palpus creamy white. 
ES 
Ficurp 57.—Antenna, front view of head, and palpus of (A) Tabanus mularis and (B) 
T. lineola. 
Female.—Length 10-12 mm. Eye bare, green, with a single, diagonal, purple 
band. Frons yellowish, about four times as high as width at basal callus, with 
nearly parallel sides; basal callus dark brown to black, slightly higher than 
wide and narrowly separated from eyes; median callus small and usually sepa- 
rated from basal callus; subcallus and genae above level of antennae, con- 
colorous with frons; rest of genae and clypeus gray, faintly tinged with yellow. 
First two antennal segments reddish brown, with rather dense, short, black 
hair, the first with some grayish pollen; third orange brown, the annulate por- 
tion slightly darker; basal portion with a distinct dorsal angle but only a 
slight dorsal excision; annulate portion slightly longer than basal portion. Sec- 
ond palpal segment moderately thick basally and tapering to a slender apex, 
pale cream colored, with black hair. 
Mesonotum olive green, unstriped; the remainder gray, faintly tinged with 
olive green. Wing hyaline, the costal cell orange brown; venation normal. 
Femora black, with greenish-gray pollen; tibiae yellow, the apical two-thirds 
of fore tibia and apices of others black; tarsi black. 
Abdomen black, with a light-yellowish-gray median stripe and an indication 
of faint sublateral stripes; venter olive green, sometimes quite dark. 
Male.—Areas of large and small facets sharply differentiated, the former 
extensive; in dried specimens the large facets yellow, the small facets black; 
palpus rather slender, with acute apex. Body coloration essentially as in 
female. 
