16 



Farmers' Bulletin 801. 



molting or at other times. This point, as well as methods of control, 

 is discussed in later pages. 



The body louse appears to pass readily from one fowl to another 

 when they are closely associated. It also infests turkeys, upon 

 which it multiplies to some extent, and it is said to occur on pigeons, 

 but has not been found on them by the writers 



THE SHAFT LOUSE. 



The shaft louse is the species spoken of by most authors as the 

 "small body louse," a name which does not fit the habits of the 

 species. Normally, it occurs along the shaft of the feathers and 



does not remain on the body of the 

 host for any length of time. The shaft 

 louse is closely related to the large body 

 louse and resembles it somewhat. It is 

 smaller, rather lighter yellow in color, 

 and somewhat less spin}^ (See fig. 12.) 

 The habits of the shaft louse will enable 

 one to separate it readily from the large 

 body louse. T\Tien the feathers on the 

 thighs or breast are parted this louse will 

 be seen nmning toward the body along 

 the shaft of the feather. Sometimes as 

 many as a dozen lice will be seen, one 

 behind another, along the feather shaft. 

 Although this species is probably the 

 most common found on chickens in 

 various parts of the country, the A\Titers 

 consider it of much less importance 

 than the body louse, chiefly because it 

 stays on the feathers the greater part 

 of the time and probaljly feeds exclu- 

 sively on the barbs of the feathers and 

 on scales along the shaft. - It is not known to occur on young 

 chickens. Seemingly the absence of feathers prevents the successfid 

 development of the species on young fowls. 



The eggs are deposited singly at the base of the feathers, hidden 

 between the mam shaft and the after shaft. It appears that eggs of the 

 shaft louse require more time for mcubation than those of the head 

 louse or the body louse, and the time required to reach maturity 

 is also greater. The shaft louse appears to live much longer on 

 feathers which have dropped from the host than any other species on 

 domestic fowls. 



Fig. 10.— Body louse: Female, underside 

 Greatly enlarged. (Original.) 



' Menopon pallidum Nitzsch. 



