60 INSECTS AFFECTING DOMESTIC ANIMALS. 
and horses being “ occasionally killed by their repeated harassing 
bites,” and while this seems to be rather strong language, and we will 
refer to it again in considering Tabanus lineola, there is no question 
that the effects are serious enough, so that it is desirable to protect 
animals as far as possible from their bites. 
With horses in use the common practice of protecting with nets is 
the most effective method we know of, but for animals in pasture it 
would be particularly desirable to find some substance which could be 
rubbed over the hair, and, retaining its properties for a reasonable 
length of time, have sufficient repelling power to keep the flies away. 
The larve are not open to successful attack, and even if they were, 
the fact that most of them are probably beneficial should deter us 
from using destructive measures against them. 
They are widely distributed, and species occur in all parts of the 
world, torturing alike the elephant and lion of the tropies and the 
peaceful reindeer of the arctic region. It is during the hottest sum- 
mer months that they are the most abundant, and they frequent both 
our timbered and prairie regions. 
The species are quite numerous, over 1,300 being known, of which 
about 150 are credited to North America. Manifestly it would be 
impossible in a work like this to even mention more than a few species, 
and, since so little is known of the early stages, there is no necessity 
for treating each species in detail. We will therefore in considering 
the species simply refer to the more common ones, the habits of 
which have been observed, and more particularly those occurring in 
this country. 
Osten Sacken’s admirable ‘‘Prodrome of a Monograph of the Taba- 
nide of the United States” in Memoirs of the Boston Society of Natural 
History (Vol. I], Part IV, Nos. 1 and 4) will enable anyone to make a 
thorough study of our native species. 
THE BLACK GAD FLY OR BREEZE FLY. 
(Tabanus atratus Fab.) 
Probably this is the largest species in the family, and it is certainly | 
one of the most conspicuous, being quite common and of such a decided 
black color as to attract attention either on the wing or when perched 
on the back of some poor animal that tries in vain to drive it off. 
Fabricius described it in 1794 (Ent. Syst., Vol. IV, p. 366). Walsh 
described its larva in 1864 (Proc. Bost. Soc. Nat. Hist., Vol. IX, pp. 
302-306), and in Riley’s Second Missouri Report (p. 128) its life history 
iS given except the egg and early larval stages. Its bite is one of the 
most severe of the tribe, but fortunately the species does not occur in 
such great numbers as the green-head fly. Its attacks seem more com- 
monly directed against cattle than horses, and it is most noticeable in 
sunny pastures, though occasionally seen perched on trees or the side 
‘ 
: 
is 
