4 8 
both make a deep hum when flying round one, quite unlike the note 
produced by the smaller Tabanida;." • 
The Museum general collection of Diptera contains specimens of 
T. sudeticus from Hungary and Spain ; additional localities given by 
Brauer show that the species is generally distributed throughout 
Europe. Writing with reference to Austria, Brauer says : — " Before 
sunrise the males hover and swarm in the air above the highest 
mountain-tops, e.g., the Dobratsch (according to Buchmuller) and 
Hohen Zinken (as stated by Frauenfeld), and sit on fences in the 
sun during the morning after emerging from the pupa ; the females 
are found on the leaves of shrubs and on cattle." 
Tabanus autumnalis, Linn. 
Plates 21 and 22. 
The striking sexual difference in the marking and coloration of the 
abdomen exhibited by this species is well shown in the plates ; the 
difference in the appearance of the head in the two sexes, caused by 
the eyes meeting together in the males, which are consequently said 
to be " holoptic," is common to all Tabanidse, as also to many other 
Diptera (compare Plates 1 1 and 26). Of Tabanus autumnalis, which 
in the South of England, according to Colonel Yerbury, is " one of the 
commonest species of the genus," the British Museum possesses nine 
modern British specimens (five males and four females), from the 
following localities : — N.E. Essex and Colchester, Essex, date of cap- 
ture unknown, ( W . H. Hanvood) ; Felden, Boxmoor, Herts, July 17th, 
1899 (A. Piffard) ; Harrow, Middlesex. July 1 5th, 1901 ( W. D. Lang) ; 
Brockenhurst, New Forest, Hants, May 30th, 1896 (Miss Gertrude 
Ricardo) ; Dunster, Somerset, August 1st, 1902 {Lieut-Colonel C. T. 
Bingham); S. Devon, — Avon Valley, May 15th, 1896, Warleigh 
Marsh, June 24th, 1889, and Tamerton Folliott, June 29th, 1889 
(Lieut.-Colonel Yerbury). The Museum general collection contains 
specimens of this species from France, Portugal, Hungary, Italy, and 
Algeria. The localities given by Brauer {loc. cit., p. 193) show that it 
