CHAPTER IV 
PARASITES OF THE RESPIRATORY TRACT 
NOSE. 
CoccIpDI1A sometimes set up nasal catarrh in rabbits. 
Linguatula Teenioides.—This is a degenerate member 
of the Arachnida. As the name indicates, the body is 
elongated, ringed, and worm-like. The anterior ex- 
tremity is broad and rounded in shape, and scarcely 
distinguishable from the thorax and abdomen. Legs 
are absent, with the exception of vestiges in the form 
of two hooks, which curve backwards at each side of 
the mouth, and which can be protruded or retracted at 
will through slit-like openings. The mouth is sur- 
rounded by a ring of chitin. 
The male is small, being usually under r inch in 
length, and white in colour. 
The female may measure 5 inches in length, and is 
greyish or sometimes almost yellow. It is quite common 
to find the parasite rolled up. 
Lire-History.—The female deposits eggs in the 
nasal cavities, from which they escape by the nasal 
discharge. If they happen to fall on grass or fodder, 
they may be ingested by another animal, and providing 
that animal be one suitable for their further develop- 
ment (ox, sheep, rabbit, sometimes a horse), on reaching 
the stomach or intestine they hatch out into larve. 
They bore through the intestinal wall into the liver or 
mesenteric glands, and become encysted there. They 
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