196 ZOOLOGY. 
The Pupipara are a singular group of insects, having the antenne (which 
are of one or two short articulations) deeply set in the head. The mouth 
is without a fleshy exsertile labium, but it is provided with a sharp spicula 
and several bristles. They are separated into two families, Hippoboscide 
and Nycteribiide. 
The Hippoboscide have a depressed, tough, and ati body, and they live 
upon beasts and birds, moving quickly (and sometimes sideways) among 
the hair and feathers. The wings, and even the halteres, are sometimes 
absent, as in Melophagus ovis (pl. 77, fig. 85), known as the sheep 
tick. The feet are short, and the claws denticulated. The larva 
remains unexcluded until it becomes a pupa, and as but one is developed 
at a time, it is, when excluded, nearly as large as the abdomen of the 
female. 
The Nycteribiide are without wings and halteres, the feet are very long, 
and so is the basal articulation of the tarsi, which present an analogy with 
the feet of some of the Arachnida in being annulated, presenting the 
appearance of being divided into numerous minor parts. These insects 
infest bats ; and from the position of the head, which is small and turned up 
on the thorax so as to be dorsal, it is necessary for them to turn over 
and stand with the back downwards when they suck. This is readily 
effected, the feet being so constructed as to allow them to stand erect or 
inverted. They move rapidly through the hair, but cannot walk upon a 
smooth surface. Some authors have classed these insects with the 
Arachnida. 
400 
