602 Marvels of the Universe 
Photo by) (HOS. Cheavin, FRM. 
A FOWL LOUSE. 
The parasite is not always a pest; he 
sometimes renders good service to his host 
by thinning the body plumage during hot 
weather. 
upon the blood of their host, yet it is probable that the 
great majority of them are, like the slender-bodied parasites 
of the duck and the pigeon, useful attendants on their 
toilet. 
The tawny owl presents by way of contrast a parasite 
that is not slender-bodied (see photograph), but which ex- 
hibits an aldermanic outline suggestive of unearned incre- 
ment. That organism, also, is seen to possess eight legs; it 
is, however, much larger than a mite, and is known as a 
melo Kou 
Ticks are not so common on birds as the bird-lice 
and the mites previously mentioned, but some bird species 
become prey for them; the swallow and the pigeon are 
hosts not infrequently selected. They are probably the 
most troublesome of all their parasites ; they are certainly 
the largest feeders. Their bodies are of a leathery consist- 
ency, and their mouth parts are adapted for penetrating 
the skin and for blood-sucking, while their feet are provided 
with sucker-like organs. 
Probably the birds acquire these troublesome visitors 
from the herbage amongst which they move, as they are 
vegetable feeders during certain stages in their development, 
and they also breed on the ground. 
It is the female tick which has to be feared, as the abdomen of the male cannot be distended with 
blood like that of the female. The latter often pumps herself up to the size of a pea. Also these 
Photo bu) [H.S. Cheavin, FRM. 
A ROOK LOUSE. 
All these examples of parasites are much 
enlarged. 
parasites are not at all particular regarding their host ; indeed, 
in this respect they are most adaptable, and it does not by 
any means follow that a tick found upon an owl is an owl 
parasite; it would probably have travelled with a hedgehog 
just as readily if fortune had turned it that way. It is 
well known to country people that dogs and horses which 
are quite clean on starting out will often return after 
hunting with some of these pests about them. Even man 
himself is often annoyed by them, for they are just as likely 
to grasp his clothes by means of their hooked feet as they 
cling to the tall grass-blades as they would the coat of a 
passing sheep or a dog; they are especially annoying at 
hay-time. It is obvious, therefore, that birds which con- 
tinually move in and out amongst vegetation while searching 
for their prey are most likely victims. 
Although the ticks do not breed on their hosts, yet it 
is obvious that some of their other parasites do, for attached 
to the quills of birds’ feathers their numerous eggs may be 
found in abundance. These tiny eggs are often beautifully 
sculptured, and under a microscope they make most charm- 
ing objects when well illuminated. 
BIND) OW WOIL, Il 
