The Bird-Lice 



jaws are usually toothed and pointed ; the legs are strong, and, 

 curiously enough, the front legs are short and are used only in 

 carrying food to the mouth. When at rest, they project forward 

 beneath the head. The whole body is usually rather hairy. 



The eggs are elongate oval and are fastened singly to the 

 feathers or hairs of the host. The young issue by breaking off a 

 circular lid at the larger free end of the egg. The duration of the 

 egg stage is not known. 



The young lice when first hatched look much like the full 

 grown lice, except that the head is comparatively larger, and the 

 markings of the body are absent or dull. Just before the last 

 molt some individuals are quite as large as the adult specimens. 

 The question as to whether they really draw blood has been 

 carefully studied. There will frequently be seen a large dark 

 blotch indicating some opaque contents to the 

 stomach, but a careful examination on dissection 

 has shown that this blotch is composed of 

 bits of feathers. One species is said by Kellogg 

 to live in the pouch of a pelican, where, of course, 

 there is no hair, and about the portion of the 

 membrane to which the lice cling the surface is 

 raw and bloody, but here Kellogg thinks that 

 the food is simply the epidermal scales of the 

 inner wall of the pouch. 



Fig. 238. Gom- , . . 



ocotes abdom- Such of these bird-lice as occur upon domes- 



inaiis. jj c fowls, while not serious pests, undoubtedly 



(After Denny.) . J 



cause poultry considerable annoyance simply by 

 the irritation of the skin by the sharp feet of the parasites. After 

 a hen affected with bird-lice dies, the insects either die or attempt 

 to leave her body by crawling slowly toward the head. Con- 

 sidering that they do not feed upon the blood, but simply upon 

 the feathers, it is curious that they should die after the death of 

 the hen. Kellogg suggests that their death is probably due to the 

 lack of animal heat to which they have been accustomed during 

 the life of the host. 



Aquatic birds are affected with bird-lice quite as abundantly 

 as those which never enter the water, and it would not be strange 

 if in the lice affecting such birds should be found some modifi- 

 cation of the breathing apparatus, but there is no such modification 

 and they are doubtless protected by the close feathers, so that 



348 



