822 



THE OKGANS OF SPECIAL SENSE. 



amount of granular protoplasm, and possessing two processes, of which one runs 

 outward between the columnar epithelial cells, and projects on the surface of the 



FIG. 438. Section of the olfactory mucous membrane. (Cadiat.) a. Epithelium, b. Glands of Bowman. 

 c. Nerve bundles. 



mucous membrane as a fine, hair-like process, the olfactory hair ; the other or 

 deep process runs inward, is frequently beaded like a nerve-fibre, and is be- 

 lieved by most observers to be in con- 

 nection with one of the terminal fila- 

 ments of the olfactory nerve. Beneath 

 the epithelium, extending through the 

 thickness of the mucous membrane, is a 

 layer of tubular, often branched, glands, 

 the glands of Boivman, identical in 

 structure with serous glands. 



The arteries of the nasal fossa? are 

 the anterior and posterior ethmoidal, 

 from the ophthalmic, which supply the 

 ethmoidal cells, frontal sinuses, and 

 roof of the nose ; the spheno-palatine, 

 from the internal maxillary, which sup- 

 plies the mucous membrane covering 

 the spongy bones, the meatuses, and sep- 

 tum ; the inferior artery of the sep- 

 tum, from the superior coronary of the 

 facial ; and the infraorbital and alveolar 

 branches of the internal maxillary, 



which supply the lining membrane of the antrum. The ramifications of these 

 vessels form a close, plexiform network, beneath and in the substance of the 

 mucous membrane. 



The veins of the nasal fossce form a close, cavernous-like netAvork beneath the 

 mucous membrane. This cavernous appearance is especially well marked over the 

 lower part of the septum and over the middle and inferior turbinated bones. Some 

 of the veins pass, with those accompanying the spheno-palatine artery, through the 

 spheno-palatine foramen ; and others, through the alveolar branch, to join the 

 facial vein ; some accompany the ethmoidal arteries, and terminate in the ophthal- 

 mic vein ; and, lastly, a few communicate with the veins in the interior of the 



FIG. 439. Nerves of septum of nose. Right side. 



