128 HORSE AND CATTLE FLIES. 
a short distance along the sides, the almost velvet-black colour pre- 
dominating above. As in bovinus, there is a central row of spots; but 
when type specimens of the two kinds are examined side by side, the 
black ground colour of sudeticus catches the eye at once. Also it is 
considered to fly earlier in the year,—sudeticus in May and middle of 
June, bovinus end of June, July and August. 
For specific differences see references below*; but though the 
insects are distinguishable by experts, they are not at all so without 
types and full description, inappropriate here; therefore, as the early 
name J’. bovinus, Linn., includes both kinds scientifically, and the 
name of Great Ox Gad Fly does so for all practical purposes, I have 
preserved the comprehensive name still often used. 
Of the other Gad Flies mentioned, the Autumnal Gad Fly, Tabanus 
autumnalis, is one of the most noticeable. This is a smaller and much 
ereyer fly than the above, not quite four-fifths of 
an inch in length. Eyes very dark, black or part 
grey, without cross-bands. Thorax black-brown 
or grey above, with five grey stripes. The abdo- 
men above of a greyish red-brown in the male, 
black in the female, in both male and female with 
three rows of white or white-grey spots. The 
eee eee Fly central row triangular; the rows (one on each 
side of the central stripe) of oval, usually white, 
spots placed slantingly from the inner and foremost to the outer and 
hindmost end of each spot. 
T. bromius, sometimes known as the Noisy Breeze Fly, is also of a 
greyish tint, but smaller than the above, being only about half an inch 
long; and the eyes with one purple cross stripe,—in the females on a 
ereen ground colour, with a reddish glance. Like autwmnalis, this 
kind has five grey stripes along the thorax, but they are more notice- 
able; also there are three stripes along the abdomen, similarly of a 
central row of triangular spots, and two slanting side rows; in regular 
course the central row whitish, the side rows yellowish, and this, 
together with the side of some of the foremost segments in the male 
being more or less of an orange colour, and occasionally something of 
the same tint in the female, gives the fly a more greyish-yellow colour ; 
also it is somewhat hairy. 
* Brauer’s ‘Tabanide’ (cited p. 127), pp. 184, 185. ‘ Dipterologische Beitrige,’ 
von P. P. Zeller, in ‘Isis,’ p. 815, 2, plate i. fig. 5-8, 1842. ‘Fauna Austriaca: die 
Fliegen’ (Diptera), vol. i. p. 34. I may be permitted to add that in case any of my 
correspondents wish for information in more detail, I have Dr. Brauer’s and Dr. 
Schiner’s works above referred to in my own library. Prof. Zeller’s work being 
only accessible with great difficulty, I have not the work itself, but large extracts 
and abstracts taken by myself from a copy kindly lent me by Mr. O. H. Janson, 
F.E.S., which I believe embody all requisite information. 
