LICE. 19 



scientifically known as Mallophaga, and are true 

 insects. Their exact place in classification is not 

 conclusively settled. They show in many respects 

 close relationship to the order Neuroptera, the group 

 of insects that includes the Dragon-flies, Lace- 

 wing-flieSj and others. They are quite distinct 

 from the Human Lice or JPediadidce, and equally 

 distinct from most of the Mammalian Lice (Hcema- 

 topince) . The true Bird-Lice have a mouth formed 

 for biting and chewing their food ; the Human and 

 Mammalian Lice have the mouth formed into a 

 piercing-organ, by which they suck out the blood of 

 their host. The Mallophaga, sometimes known as 

 the Ricinidce, subsist upon the productions of the 

 skin. They also devour the fragments of feathers, 

 and even (sometimes to a most alarming extent) feed 

 upon the barbs of the feathers, especially attacking 

 the saddle-hackle — the feathers of the latter showing 

 curious jagged and notched edges in lice infestation. 



Closely related, however, to the Bird-Lice are 

 some Mammalian Lice, or Ticks, known as Tricho- 

 dectes. These so-called Ticks are quite distinct from 

 the general run of Mammalian forms and are very 

 abundant. They are provided, like the Bird-Lice, 

 with a biting-mouth, but they can at once be dis- 

 tinguished from the latter by the structure of those 

 remarkable sensory organs common to all insects, 

 namely the antennae or ' feelers/ 



On examining one of the commoner Bird-Lice, 

 these antennas will be found to be composed of either 



C2 



