450 C. R. OSTEN SACKEN'S PRODROME 



portion rather long, Ijlack (in some specimens the third joint is brownish). Thorax bhickish- 

 gray, with a pale yellowish pnbescence and scattered black, erect pile ; no whitish lines, 

 bnt a hardly perceptible vestige of a broad, longitndinal stripe of purer gray in the middle. 

 Pleun\3 didl ^-ellowish gray. Abdomen with a whitish longitudinal stripe, running from the 

 scutelluin to the end of the sixth segment ; it is enclosed between two blackish stripes run- 

 ning beside it ; on each side of the blackish stripe there is again a very faint whitish one, 

 usually visible on segments four to six only ; Ijase of the first segment blackish, but sides of 

 sesments one to three reddish. Venter reddish at base, with more or less black in the 

 middle in the shape of a stripe, blackish towards the tip. Femora black, clothed with gray- 

 ish pollen, the tips pale reddish; front tibiae black, reddish brown on their proximal half; 

 front tarsi black; four posterior tibia? reddish, except the tip, which is infuscated (more so 

 on the hind than on the middle pair) ; tarsi brown. Wings hyaline, costal cell yellowish, 

 stio-ma vellowish. Lenn'th, 9-11 mm. 



Male. Like the female, but the thorax somewhat darker, the yellowish pubescence 

 being less apparent, and the Ijlack erect pile more so and longer ; face more grayish ; the 

 head, in size and outline, not very different from that of the female. Length, 10 mm. 



Hah. Massachusetts, Ehode Island, New York, New Jersey, especially near the sea- 

 coast ; (Cambridge, Mass., June 28-Jul_y 15, P. Pi. Uhler and 0. Sacken ; Salisbury Beach, 

 Aug. 25, in numbers, B. P. Mann). I have sixteen females and ten males. The eyes are 

 like those of T. cosfalis, light green, with a single purple crossband in the middle ; it 

 seems to me that this band is somewhat narrower here. 



This species has some resemblance to 7\ cosfalis Wied., but is much smaller, and less 

 yellow on the thorax; face and palpi also less yellowish; the black abdominal stripes enclos- 

 ing the whitish ones are less dark ; the white stripe between them is much less distinctly 

 marked than in T. cosfalis ; the hind tibiie are only slightly brownish here at the tip, while 

 in T. cosfalis the tip is very distinctl}^ and rather al>ruptly black. 



The males, especially, are easily told apart, the thorax of T. nigroviffafns i , being 

 blackish, that of T. cosfalis very distinctly yellow; in T. niyroviffafus i , there is, on each 

 side of segments one to three of the abdomen, an oval rufous spot, leaving a well defined, 

 Ijroad, Ijlackish stripe in the middle, in the middle of which the Avhite stripe is running ; in 

 T. cosfalis i , the extent of the rufous on the abdomen is much more variable, and hence 

 the black stripe in the middle less constant and Avell defined. From T. lineola the present 

 species differs in the smaller size, parallel front, less pure whitish, more yellowish white 

 face, the yellowish tinge of the costal cell, etc. 



1 see no objection against identifj'ing this species with Macfj^uart's description, except the 

 " une tache testacee en avant des ailes et sur les cotes du bord posterieur," which I per- 

 ceive only in the male, while Macquart describes the female. Before identifying this spe- 

 cies with Macquart's I distributed specimens to several corresj^ondents under the name of 

 T. ■pauper. 



25. Tabanus costalis. 



Tahanvs costalis Wiedomiinii, Auss. Zu'., I, p. 173, 94 ; (?) Bcllardi, Snggio, etc., I, ji. 03. 



Tahanus vicnrius W;ilkor, List, etc., I, ]i. 137 ; female. 



{?) Tahanus halt imoren sis Mnequart, Dipt. Exot., 5'= Suppl., p. 34, 129. 



Female. Face yellowish white, palpi yellow, with short and rather dense black hairs ; 

 second joint rather stout at base ; front grayish yellow, very slightly uarroAver anteriorly, 



