Dec, 1906.] North American Species of Tabanus. 25 



black, first segment a little larger than the same in costalis, third 

 segment not especially wide, a well defined basal prominence, 

 annulate portion about the same length as the basal ; legs mostly 

 reddish; anterior femur on the upper side, anterior tibia at apex 

 and all the tarsi dark; wing hyaline with a small brown stigma; 

 abdomen brown, in some specimens notably darker than in 

 others, with three yellow, :niddorsal stripe reaching the apex, 

 the lateral ones abbreviated behind. 



Female: Length 12-15 mm., front rather wide, slightly 

 narrowed below, clothed with yellowish-brown pollen and a few 

 hairs; callosity pale brown, nearly square with a very slender 

 connected line above; thorax above rather dark, clothed with 

 gray pollen and dark hair, face and sides of thorax with white 

 hair. 



Male: Length 12-15 mm., head with an extensive area of 

 large facets, small facets behind the large ones compose a band 

 entirely behind the point where the eyes unite at vertex; thorax 

 a little lighter than in the feamle and clothed with longer hair. 



The eyes in this species are plainly pilose in the female as well 

 as in the male and by this it may be known from others. The 

 very pale frontal callosity in the female is also distinctive. Many 

 specimens taken at San Jose, Guatemala, February 5, 1905. 

 They were taken by beating a large grass that grew only a few 

 yards back from the beech. 



Tabanus lineola Fabricius. This common species is known 

 from all the others mentioned in this paper by the oblique, 

 angular and connected row of spots on each side of the abdomen. 

 It is the only one of these species that has any suggestion of 

 stripes on the thorax. Length about 14 mim. 



Tabanus modestus Wiedemann. Length 13-15 mm., general 

 color black; antenna red, first segment enlarged with black hairs 

 above, third segment with a prominent basal process, annulate 

 portion darker in color than the basal ; front of normal width, 

 slightly narrowed below, clothed with yellow pollen, callosity 

 shining black narrower than the front and with a connected line 

 above; thorax above grayish-black; wing uniformlv dilute 

 brownish with a darker stigma ; legs black except the base of each 

 anterior tibia which is white, and all the other tibiae which are 

 reddish except extreme apexes; abdomen with a middorsal nar- 

 row white stripe, and a more or less obscured stripe of the same 

 color on each side only reaching the third segment. 



Specimens are at hand from San Carlos, Costa Rica. The 

 size in conjunction with the color of wings and body serve to 

 distinguish this from other species here mentioned. 



Tabanus nigrovittatus Macquart. General color similar to 

 costalis; antenna reddish, first segment slender; third segment 

 with an angle above, annulate portion black, slightly longer 



