44 VETERINARY PARASITOLOGY 
buzz of the mosquito when flying. They are gregarious, 
and move in flocks, settling occasionally, but never 
appearing to rest for any length of time. The larve 
are aquatic. Only the females are blood-suckers. They 
attack only unprotected portions of the body, as the 
mucous membranes, especially the conjunctiva and the 
skin over the inside of the thighs and ears. They punc- 
ture the skin, producing raised swellings and intense 
irritation, followed by desquamation of the epidermis. 
Occasionally, when a large number attack the skin, 
serious symptoms may result. The chief are dyspneea, 
associated with fever, which may be followed by death. 
The Brachycera 
are flies with short antenne. Usually they are winged, 
and have the posterior pair rudimentary. Larve 
apodal, with no distinct head. The chief families are: 
Tabanidz (breeze-flies). 
Muscidz (house-flies). 
(Estridz (bot-flies). 
Hippoboscide, or Pupipara. 
RODH 
I. Tabanide (Breeze-Flies). 
These have a broad, flattened body, and the head 
broad and flattened from before to behind. The pro- 
boscis is capable of piercing the thickest hide. These 
flies are distributed all over the world, and are to be 
seen in the heat of the day, usually in the neighbour- 
hood of woods, where, by the buzzing sound they make 
during flight, they strike terror into cattle and horses in 
the neighbourhood. 
The breeze-flies are responsible for the spread of surra, 
and it is not unlikely that they might convey the bacilli 
of anthrax. 
