458 C. R. OSTEN SACKEN'S PRODROME 



Pleura3 with a whitish down and with longer white hairs, especially between the root of the 

 wings and the base of the abdomen ; abdomen covered with a thin whitish elllorescence, not 

 concealing the gronnd color, but visible in an oblique light ; it is more perceptible along 

 the hind margins of the segments, where, on each side, it becomes broader and very dis- 

 tinct ; hind margins of the ventral segments also whitish. Legs brownish red, tarsi darker; 

 hind tibiaj with fringes of dark hairs. Wings hyaline, costal cell and stigma infuscated ; 

 first posterior cell somewhat coarctate. 



Male. Head large, subhemispherical, like that of T. atraius in shape ; the large facets 

 occupy a very extended area, and are distinctly separated from the small ones. Hairs on 

 head and chest more yellow than in the female. (I have only a single specimen, from 

 Florida, before me.) Length, 25-30 mm. 



Hob. Middle and Southern States. I have seen specimens from Illinois ; Sea Islands, 

 S. C. ; Florida (Ft. Capron, Fla., April 25, Messrs. Hubbard and Schwarz) ; Kentucky; Mis- 

 souri ; Pennsylvania; Detroit, Mich. (Mr. Hubbard). From Mr. Akhurst I received a 

 specimen caught in the State of New York. 



Fiirster's name, being the oldest (1771), should have the priority. Drury's description 

 and figure are older, but the name T. plumbeus Drury, appears only in Vol. II, Appendix 

 (1773). Forster is wrong in quoting Drury's figures, 2 and 3 ; the latter is T. americanus 

 Drury (Syn. atraius Fab.). This is the largest of the North American Tabani, and seems 

 to be very common in some parts of the south and west. The eyes are unicolorous, of a 

 brilliant green. 



37. Tabanus giganteus. 



Tabanus giganteus DcGacr, Ins., VI, p. 226, 1 ; Tab. XXX, f. 1. 



Tabanus litieatus Fabriciiis, Spec. Ins., II, p. 455, 4; Entomologia System., IV, p. 363, 5; Syst. Antl., p. 

 94, 3.— Wiedemann, Dipt. Exot., I, p. 63, 3; Auss. Zw., I, p. 115, 4. 

 ? Tabanus bicolor Macqiiart, Dipt. Exot., 2' Snppl., p. 34, 129 ( ? ). 

 ? Tabanus ccesiofasclatus Macquart, Dipt. Exot., 5° Suppl., p. 32, 126 ( ,5 ). 



Female. Front rather narrow, grayish ; frontal callus chestnut brown, prolonged up- 

 wards as a narrow, smooth line ; face whitish yellow or yellowish white ; palpi reddish 

 yellow, beset with golden yellow and black hairs. Antonnte I'ed, third joint deeply excised, 

 upper angle projecting, horn-like. Thorax brownish above, more or less clothed with gray- 

 ish pollen, with indistinct darker stripes and reddish lines between them ; scutellum usually 

 reddish, with a black spot at the base. Pleuras and pectus clothed with j^ellowish or whit- 

 ish hairs. Abdomen blackish, more or less covered with a white efllorescence ; the sides of 

 the abdomen, especially on the second segment, reddish ; incisures more or less whitish. 

 Legs brownish red ; tarsi darker ; hind tibiae with a fringe of black hair. Wings tinged 

 with pale brown; costal cell and stigma ferruginous brownish; first posterior cell but 

 slightly coarctate. Length, 22-25 mm. 



Hab. Middle and Southern States. I have seen specimens from Connecticut (Suffield, 

 G. Dimmock), Pennsylvania, Illinois, Missouri, Arkansas, Sonora. Dr. Harris's Catalogue 

 quotes this species from Massachusetts. 



The eyes of this species are unicolorous. DeGeer's T. giganteus is evidently this spe- 

 cies ; about the confusion existing between it and T. calens Linne, see Wiedemann, Auss. 

 Zw., I, p. 135. 



