4i 
that the female specimen illustrated in Plate 15, which was taken by 
Colonel Yerbury at Aviemore, Inverness-shire, on June 5th, 1904, has 
a small appendix to the upper branch of the third vein in each wing, 
and traces of a similar appendix are to be seen in some of the other 
specimens in the Museum. In the British Islands TJierioplectes luridus 
would appear to be a northern species, and as yet the Museum 
possesses no specimens from either England, Wales, or Ireland. 
Colonel Yerbury writes : — " In Scotland this is the earliest of the 
Tabanidse. In May 1905, it was met with in numbers near Nairn, 
when both sexes were found sitting on a sandy road leading to 
Mairston Sand Hills. A single female was taken at Aviemore on 
June 5th, 1904. Probably all the Tabanidae seen by me in Scotland 
at this time of the year belonged to this species." The Continental 
specimens of this species in the Museum collection are all from 
Norway; additional localities given by Brauer are Swedish-Lapland, 
Sweden, Poland, Silesia, and Bohemia. 
Therioplectes tropicus, Pz. (nec Mg.). 
(Form bisignatus, Jacnn.) 
Plate 16. 
In its typical form this species has an ochraceous or ochraceous- 
buff patch on each side of the abdomen extending from the posterior 
angles of the first to the posterior margin of the third or anterior 
border of the fourth segment, leaving a broad median black stripe 
one-third of the abdomen in width. Two males in the possession of 
the Museum from Oxshott, Surrey, June 9th, 1895 {Lieut-Colonel 
Yerbury and IV. R. Ogilvie Grant), and Chattenden Roughs, Kent, 
July 1 2th, 1902 {H. W. Andrews), respectively are of this character, 
but the whole of the British females in the Museum series [15] are of 
the melanochroic form bisignatus, of which a specimen is illustrated 
in Plate 16, which accordingly would appear to be the common 
British form of the female of this species. As a further proof of this 
conclusion it may be mentioned that at Oxshott on June 9th, 1895, 
