CHAPTER XIII 

 ORDER MALLOPHAGA* 



The Bird-lice 



The members of this order are wingless parasitic insects with chewing 

 mouth-parts; cerci absent. Their development is without metamorphosis. 



The bird-lice are small wingless insects. The more common species 

 range from -£- s of an inch to | of an inch in length. The bodies of 

 these insects are flattened and usually have broad distinct heads with the 

 antennas short and either exposed or hidden in grooves on the underside 

 of the head. Bird-lice vary in color from almost white to yellow, tan, 

 brown or nearly black with or without distinctive markings. The mouth- 

 parts are on the underside of the head. The mandibles are large and 

 prominent and the clypeus is enlarged into a conspicuous flap. Degen- 

 erate eyes are present on the margins of the head. 



The bird-lice resemble the true lice in form and in being parasitic 

 but they feed upon hair, feathers and dermal scales, while the true lice 

 (Anoplura) have sucking mouth -parts and feed upon blood. 



The Mallophaga infest chiefly birds and on this account the term, 

 bird-lice, is applied to the entire group; a few forms, however, are para- 

 sitic upon mammals. For the most part the tarsi of those species that 

 live upon mammals have but one claw which can be clamped against the 

 tibia thus forming a structure well adapted for clinging to hairs. Those 

 species which infest birds have two claws on the tarsi which are better 

 adapted to running among feathers. The white eggs of the bird-lice are 

 glued singly or in groups to the feathers and the development takes 

 place on the body of the host. 



Bird-lice injure their hosts through the constant irritation which 

 they cause by feeding on the dermal scales and by scratching the skin 

 with their sharp claws during their incessant movements over the body 

 of the host. It is to free themselves from these pests that birds wallow 

 in dust. When poultry are kept in closed houses they should be provided 

 with a dust bath. In addition the fowls should be treated with a pinch 

 of sodium fluoride on the head, beneath each wing, on the back and 

 underside of the abdomen, and two or three pinches beneath the tail 

 feathers. It has also lately been discovered that nicotine-sulphate 

 smeared on the perches just before the fowls go to roost will destroy all 

 of the lice. 



The body-louse of the hen, Menopon biseriatum, is the largest louse 

 on the hen; it is about -^ of an inch in length. It is yellowish in color 

 and is found all over the body of the hen and is probably the most 



* Mallophaga: mallos (na\\6s), wool; phagein (4>aytli>) , to eat. 



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