A VETERINARY ENTOMOLOGY FOR INDIA, PART XIV.*

                                           BY

        T. BAINBRIGGE FLETCHER, R.N., F.L.S., F.E.S., F.Z.S.,

             Imperial Entomologist to the Government of India,

                                        AND

                         S. K. SEN, M.Sc., F.E.S.,

    Assistant Veterinary Research Officer, Imperial Institute of Veterinary Research,
            Muktesar (lately Assistant to the Imperial Entomologist).

             (Received for publication on the 10th April 1031.)

                                  (With Plate IX.)

    The Tabanidae—also known as Gad-flies, Horse-flies, Dans—comprise a very large
family of Diptera characterized by thick-set bodies, large heads and very large eyes.
In the female the eyes are separated by a fairly broad band (dichoptic), while in the
male the eyes are contiguous (holoptic). In life the eyes frequently exhibit
brilliant golden-green and purple markings, but after death the colour of the eyes
rapidly changes to dark-brown, until scarcely a trace of the markings remains.
The frontal portion of the head is usually furnished with small dark longitudinal or
transverse callosities or calli, which are of importance in classifying the flies. The
antennæ are porrect and consist of three segments, the third segment being
annulated ; the arista is absent.

    The Family includes about 2,000 described species of which about 300 are
palaearctic, about 300 North-American, the remainder being natives of South
America, India, Africa and other tropical countries [Efflatoun Bey, 1930]. In 1927
Senior-White estimated a total of 126 species for the Indian Region, and Kröber
and others have since recorded a few more, raising the Indian total to probably
about 135 described species, but undoubtedly many more await discovery within
Indian limits.

    * (Continued from Vol. IV, Part IV of the Jour. of the C. B. for Animal Husbandry and Dairying
in India.)

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