196 
ST. HELENA. 
Syritta, St. Farg. 
S. pipiens, Linn. A long, thin, black Fly, with yellow rings 
round the body, somewhat like a miniature wasp; occurs very 
plentifully in the Island, and, during the day-time, may he seen 
hovering around garden plants, especially fennel bushes, both on the 
high and the low lands. 
S. spiniferella, Thoms. 
Fam. CEstrida. 
Grasterophilus, Leach. 
G. equi, Linn.— The common Bott-fly, best known in the 
Island as the Horse or the Donkey-fly. It is not very abundant, 
but most annoying to both horses and donkeys, which become 
almost frantic when one of them is near. The latter animal, in its 
endeavours to escape from one of these insects, has been known 
to fall over a precipice and break its neck. Horses become 
almost unmanageable when attacked, or even long before, as they 
seem instinctively to know when a bott-fly is near. Upon one 
occasion the horse I was riding jumped about the road in a ridiculous 
manner lor some minutes before I could detect the immediate 
presence of one of these flies. I endeavoured to get away from it 
by a smart gallop, but in vain; there it was alongside of us imme- 
diately we stopped. After dismounting, it was near half an hour 
befoie I was able to capture it, which at last I accomplished by a 
blow of my riding-whip. That identical specimen, though some- 
what mutilated, is the one which has been examined by Mr. 
Walker. I never saw a horse more frightened than on this 
occasion ; it trembled from head to foot, and seemed fully to 
undei stand what had happened when the creature was killed. 
Fam. Tachinidce. 
Tachina, Fabr. 
*T. sp. ? A medium-sized Fly, somewhat resembling the 
common house-fly. Mr. Walker has deferred giving a description 
of this insect. 
