VETERINARIAN 
VOL. XII, No. 139.] JULY 1839. [New Series, No. 79. 
COMPARATIVE ANATOMY AND PATHOLOGY. 
By Mr. YOU ATT. 
LECTURE XXIV ( Concluded ). 
The Mucous Membrane of the Nose — The supposed Influence of 
the fifth Nerve — Magendie's Experiments — The peculiar Sen- 
sation of Smelling belongs to the Olfactory Nerve — Instance of 
the peculiar Acuteness of the Nerve of Smell — The Influence of 
certain Diseases on the Sense of Smelling — Observations on 
Scent in Hunting — Anecdote of the Sense of Smell in a 
Canary-Bird. 
The Ethmoid and Turbinated Bones, on which I have described 
the olfactory nerve as ramifying, are covered with mucous mem- 
brane, a soft and extremely vascular substance lining the passages, 
by which the internal portions of the frame communicate with the 
external air. It derives its name from the peculiar character of its 
secretion. It lines all the neighbouring sinuses, one of whose 
offices, and the principal one, is to provide a sufficient quantity of 
adhesive fluid to protect and to moisten the membrane covering 
these bones and the septum narium. The ethmoid and turbinated 
bones, and the septum, being in close approximation, and covered 
by this adhesive substance, most of the odoriferous particles which, 
floating in the atmosphere, enter the nasal cavity in the act of in* 
spiration, are stopped in their course. A few of those which are 
of a gaseous character reach the larynx; but most of those which 
penetrate to this second guard are arrested there. 
It is essential to the perception of odours that this membrane 
should be constantly moist. When, at the commencement of ca- 
tarrh, the mucous secretion is diminished or suspended, and the 
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