6 
Black American Gad Fly, the Tabanus atratus. This 
family is scientifically known as Tabanidce. 
Tabanus atratus, larva and pupa; after Eiley. 
The family of the true Bot Flies, or ( Estridce , on some 
of which I am about to speak to you, are easily dis¬ 
tinguishable from the above. The perfect Flies, with a 
few exceptions, have nothing that can be called a mouth, 
and do not feed when in the Fly-state; the maggots 
feed within the hide, or in the viscera, or some parts of 
the internal cavities of the animals, and are without 
distinct head or mouth; the chrysalids are formed by 
the maggot-skin contracting and hardening, and forming 
a case for the Fly within, just as happens with the 
maggots of Beet, or Onion, or Cabbage-root, or many 
other Flies. 
With regard to this terse, not to say somewhat vulgar, 
word “Bot,” which is given to the maggots, from which 
the Bot Flies take their name, we seem here to have 
just the same word which is made use of by German 
