DIPTERA OK TRUE FLIES. 209 



of the posterior borders of the first to the fifth segments ; the 

 under-side of the abdomen orange colour. Eyes green. Wings 

 yellowish-brown, veins yellowish in places. Legs dark-brown, 

 except tibia, which are yellowish-red. The female has a curious 

 coppery sheen over the green eyes, and the abdomen is flatter 

 than in the male. An allied species, called T. sudeticus, is 

 often mistaken for T. hovinus, but can at once be told by the 

 eyes being brown, with a coppery sheen. T. autumnalis is also 

 common : it is much smaller than the above, not much larger 

 than five-sixths of an inch in length ; its general appearance 

 is grey, the thorax having five grey stripes ; the greyish-brown 

 abdomen has three rows of paler grey spots, the central one 

 somewhat triangular. 



Another nasty biting fly is Chrysops ccecufiens, a fly about half 

 an inch long ; body with black and yellow markings. Eyes 

 golden green, with brilliant purple spots and lines ; wings black, 

 with pale spaces in the male ; transparent, banded with black in 

 the female. As far as is known, they all feed in their larval 

 state in the ground, and amongst decaying wood and vegetation. 

 The larvae are long, cylindrical grubs, yellowish-white in colour, 

 with dark transverse bands ; they are somewhat enlarged in the 

 middle, and change to naked pupae (fig 102, e) in the soil. 

 The adults come forth much in the same way as the crane-fly : 

 these immobile pupse can be told by the six spines on the last 

 segment (in Tdbanus bovinus). The Tabanidse are chiefly 

 abundant in well-wooded places, especially where- water is near. 

 The warmer the day the more ravenous and bloodthirsty the 

 females become — at least that is my experience in Norway and 

 Switzerland, where animals sufier much more from them than 

 they do even in the New Forest. Tabanidse can produce a loud 

 buzzing noise, and frighten stock, just as do the Warble-flies, 

 but the noise made by TabanidaB is much sharper than the dull 

 hum of the CEstridae. 



A good jilan to keep these pests off hor.ses that I have seen 

 employed in the Bernese Oberland is to dress the horses over 



o 



