NOSE (.1S. Holm, ,ware, 011(:. nasn. I :yr. use, nose; connected with Lat. imsits, Lith. nosis, O('hurell Slay. Ski, tors, nose). The nose is not only the organ of smell. but is likewise part of the apparatus of respiration and voice. Considered anatomically, it may be divided into an external part the projeeting portion. to which 111, 11.1111 1141,e is popularly restrieted; and an internal part. consisting of two chief cavities. the /11/N11/ (assn', 1.e1):11':111.11 one another by a septum. and subdivided by spongy or turbinated eells. or siausrs in the etlittioid, sphe noid. frontal, and superior maxillary hones coin. noinicating by narrow apertures.
The external portion of this organ may be described a., a triangular pyramid which pro jeets from 1110 centre of the fare. immediately the upper lip. Its summit or root is connected with the forehead means, of a nar row bridge, formed on either side by the nasal bone and the nasal process of the superior maxil lary bone. Its lower part presents two horizontal elliptical openings. the nostrils, which overhang the mouth, and are separated from one another by a vertical septum. The margins of the nos triis are usually piltvided with a number of stiff hairs ( ribrisme), which project across the open ings. and serve to arrest the passage of foreign substances which might be drawn up with air intended for respiration. The skeleton or frame work of the nose is partly vomposed of the bones forming the top and sides of the bridge and partly of cartilages, there being on either side an upper lateral and a lower lateral cartilage, to the latter of which are attached three or four small car tilaginous plates. termed sesamoid eartilages; there is also the cartilage of the septum which separates the nostrils, and is in association pos teriorly with the perpemlieular plate of the ethinoid, and with the comer, forming a complete partition between the right and left nasal fosstr. It, is the lower lateral, termed by some writers the alar cartilage, which by its flexibility and curved shape forms the dilatable chamber just within the nostril. The nasal cartilages are ble of being slightly moved. and the nostrils of being dilated or contracted by various small mus cles, which it is unnecessary to describe.
The nasal fossil-. which constitute the internal part of the nose, are lofty, and of considerable depth. They open in front by the nostril., and
behind they terminate by a vertical slit on either side in the upper part of the ph arynx. above the sl)ft, palate. and near the orifices of the Eustachian tubes, which proceed to the tympanic cavity of the car.
The nu :coons membrane lining the nose and its cavities is called pituitary, from the nature of its secretion, or Sehneiderian. from Schneider, the first anatomist who showed that the secretion proceeded from the mucous membrane, and not as was previously imagined, from the brain ; it is continuous with the skin of the fare at the nostrils, with the mucous covering of the eye through the lachrymal duet (see Ella. and with that of the pharynx and middle par posteriorly. (In the septum and spongy bones bounding the direct passage from the nostrils to the throat, the lining membrane is vomparatively thick, partly in consequence of a multitude of glands being disseminated beneath it. and opening upon it, but chiefly, perhaps. the iire.enee of ample and capacious subinneous plexuses of both arteries and of which the latter are by far the more large and tortuous. These plexuses, lying as they in in a region exposed more than any other to external cooling indite:lives. appear to be designed 10 promole the warmth of the part. and to elevate the temperature of the air on its passage to the lungs. In the vicinity of the nostrils, the mucous membrane exhibits papilhe and a sealy epithelium, like the cor responding parts of the skin. In the sinuses, and in all the lower region of the nose, the is of extreme delicacy, being of the columnar variety, and clothed with cilia. in the upper third of the nose—which, 11c proper seat of the sense of smell. may be termed the olfactory 4 region—the epithelium elmnges from ciliated to columnar, and ;assumes a more or less rich sienna-brown tint. and increases remarkably in thiekness. so that it. forms an opaque soft pulp upon the surface. It is composed of an aggrega Lion of nucleated particles, of nearly uniform appearance throughout. except that the lowest ones are of a darker color than the rest, from their containing a brown pigment in I heir in terior. The olfactory region abounds in glands, apparently identical with sweat glands, which dip down in the recesses of the submucous tissue among the ramifications of the olfactory nerve. They are named Bowman's glands.