388 THE ZOOLOGIST. 
either side at the base uf the halteres, to be found with some 
little trouble, that suggest ear-drums. 
The nuptial ceremonies of the short-lived flies are various. 
Friday, the 23rd of August, 1907, was fine, cloudy, and chilly in 
Devonshire, the wind blowing over the tors from the north, and 
the Swallows were flying high and wildly at noon in the scant 
sunshine of a woodland nook, where a wild clematis hung in 
festoons from a larch tree sixty or seventy feet high, up which it 
had clambered to the very top, a buzz as of bees fell on the ear 
that proceeded from a congregation of Drone Flies (Hristalis 
tenax) that were poising and chasing over the bushes on pairing 
intent; and in the pine forest of Bagnoles, in Normandy, on the 
28th of July, 1908, I watched a male and female Crorrhina 
oxycathe chasing round and round among the ferns and whortle- 
berry-bushes until they coupled. In Bingley’s ‘ Animal Bio- 
graphy’ we read that the males of Tabanus bovinus and Chrysops 
cecutiens are fond of flowers, and that towards the close of day 
they are frequently seen to fly round and round in the air for the 
purpose of inviting their females, who prefer to prick animals 
for their juices, sending the cows wild with terror. I once 
encountered a terrible swarm of ‘‘clegs’”’ or forest flies in the 
fir-woods at Fribourg, in Switzerland; I never saw the like in 
England or in Scotland. On the 17th of August, during the 
drought that prevailed at the commencement of the autumn of 
1908, I found myself on a hillside above the ‘ Dartmoor Forest 
Inn’ amid a noonday swarm of circling Breeze Flies (Gastro- 
philus equ), that the Rev. Mr. Kirby calls ‘‘ horse-bees ’—grey- 
brown, mousy ‘‘bumbles”’ with faded wing-spots they seem to 
be, and yet two-winged flies. Those I captured were males, and 
when confined in pill-boxes they whined with all the impetuosity 
of bees whose brains seem confined in too small a body. Solier 
says:—‘‘ On the 9th of July I saw two Chrysotoxum arcuatum 
perched, one on the branch of a fir and the other on the leaf of a 
neighbouring beech, and both were uttering a shrill sound ; 
flying away, they returned and settled nearer one another, and 
recommenced their song. When in the air they seemed to seize 
one another, and sometimes they fell to the ground. When they 
settled again and began to hum I plainly saw a vibration of the © 
wings, and the sound intensified as it increased. The species of 
