CHAPTER V. 
SUBORDER MALLOPHAGA 
Bird Lice. 
This group embraces all the biting lice infesting birds and mammals. 
They are very distinct, indeed, from the preceding group, although fre- 
quently placed with them under such unnatural divisions as Anoplura, 
Pediculines, etc. 
Their bodies are usually hard and horny and much flattened. They 
possess mandibulate mouth parts adapted to cutting and biting the 
hairs, feathers, epidermal scales, or excretions on the bodies of their 
hosts. They are said also to have a suctorial organ by means of which 
they may at times draw blood from the host animal. The mandibles 
are situated in most forms underneath the head and near the center, 
the clypeus projecting and forming the most anterior portion of the 
head. The labrum is present and the maxillary palpi are prominent in 
a part of the group. The eyes when visible are located back of the 
antenne. The antenne are five-jointed except in Trichodectes. The 
thorax is generally narrow and frequently but two divisions are appar- 
ent. The legs are adapted to clasping (Philopterid) or to running 
(Liotheidie), the tarsi in the first case being short and fitted for folding 
against the tibiew, and in the second case being long, well adapted to 
running, and provided with two claws. The members of the first divi- 
sion occur on both mammals and birds, those of the second, except 
Gyropus, are limited to birds. Wings are entirely wanting, and the 
abdomen contains nine or ten segments and is usually oval in shape, 
In life history this group agrees with the preceding. The eggs are 
glued to the hairs or feathers of the host animal and open with a cir- 
cular cap or lid at the free end. The larve are less flattened, shorter 
in proportion, and without the hardened parts common to the adults 
covering a part or all of the surface. The length of life and rapidity 
of multiplication has not been determined for any species so far as we 
know, and the habits of the insects make any such determination a 
matter of great difficulty. 
While it is, of course, very desirable that a more complete knowl- 
edge of the life history of the species be secured, it may be considered 
as already established that all the species, with no known exception, 
pass their transformations or the body of the fowl, and that, unlike 
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