196 ZOOLOGY. 



The Pupipara are a singular group of insects, having the antennae (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, Hippohoscidcc 

 and Nycterihiidoi. 



The HippohoscidcB have a depressed, tough, and hairy 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 {pi. 77, jig. 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 NycterihiidcB 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 



