OF THE TABANID^ OF THE UNITED STATES. 427 



that, whenever a species possesses that tubercle, it must be looked for among those with 

 pubescent eyes, even when the pubescence is not apparent. Hitherto I have found only 

 four North American species which have pubescent eyes and no ocelliyerous tuherde. 

 Two of them {T hicolor {md fidvescens) at the same time have no frontal callosity, and for 

 this reason cannot be easily mistaken. The two others are T. Reiiiwardt'd and T. cerastes, 

 and for both a double reference has been introduced, so that the right names will be found, 

 even if the pubescence of the eyes should l)e overlooked. The same precaution of a double 

 reference will be found for T. rhombicus, whose ocellar tubercle is indistinct. 



2. Of T'. J/ei/er^ei I have a single damaged specimen; I place this species hypotheti- 

 cally among those with glabrous eyes, and, consequently, without ocellar tubercle. 



3. The table has been constructed principally for female siaecimens. Male specimens 

 also can be determined by it, but with a certain caution, as the abdominal markings, which 

 were used a great deal for the discrimination of the species, are generally less well defined 

 in that sex than in the females. 



4. I need hardly add that the table will be found useful for determining normally col- 

 ored and tolerably well preserved specimens, and not for very aberrant or ill-used ones. 



ANALYTICAL TABLE OF THE SPECIES. 



f Eyes gl:ibrous; ocelligerous tubercle absent 2. 



1. ■{ Eyes pubescent ; ocelligerous tubercle absent 38. 



L Eyes pubescent ; ocelligerous tubercle present (subgenus Theriophctes) 41. 



J Abdomen witb definite white markings ^ (altogether white in No. 18) 3. 



O Abdomen without any definite white mariiings 28. 



'The white maikings of the abdomen consist in a single longitudinal row of white triangles. . . 4. 



The white maikings, etc., consist of two or three rows of white triangles or spots 16. 



The white markings, etc., consist in a distinct white or yellowish longitudinal stripe, running from the 



scutellum to the end of the si.vth segment 24. 



Wings distinctly spotted or clouded witli brown (spots sometimes faint only in No. 5) ; antennze uni- 

 formly red 5. 



Wings distinctly spotted or doudetl with brown ; third antennal joint red, but its attenuated portion 

 -{ black or brown 9. 



Wings with more or less faint clouds on the crossveins and the bifurcation of third vein ; prevailing 

 color of the antennae black or brown 11. 



Wings without any vestiges of clouds on the crossveins and on the bifurcation of the third vein . 13. 



Longitudinal veins of the wings broadly clouded with brown ; frontal callous much longer than broad, 



brownish red ; first posterior cell broadly open 1. turbidus Wied. 



I Crossveins and bifurcation of the third vein alone clouded with brown 6. 



Prevailing color of the front femora dark brown 7. 



Front feniora altogether red 8. 



_ , Front tibiae brown at tip 2. fronto n. sp. 



Front tibiae altogether red 3. triligatus Walk. 



Brown spots on wings large and conspicuous; third antennal joint almost crescent-shaped, its u|ii>er 

 angle being drawn out in a long point 4. fuscopunctatus Macq. 



Brown spots on wings but little conspicuous; third antennal joint not crescent-shaped; abdomen co- 

 arctate posteriorly; abdouiinal triangles long and narrow 5. catenatus Walk. 



1 1 call (hfinile viarkinrjs the triangular spots, or oblique and not the whitish or yellow coloring of the hind or lateral 

 lateral spots, or the dorsal line, which occur in some species, margins of the segments. 



3. < 



