PRACTICAL CONSIDERATIONS: THE NASAL CAVITIES. 1417 



FIG. 1182. 



ICOUS 



mbrane 



Vomerine 

 cartilage 



the crescentic groups of serous cells that stamp the glands as mixed (Stohr). 

 Exceptionally exclusively serous glands are also encountered (Kallius). 



Jacobson's Organ. Mention has been made of the rudimentary structure 

 (organon vomeronasale) found in man, almost constantly in the new-born child and 

 frequently in the adult, as a representative of the organ of Jacobson that is present, 

 in varying degrees of perfection, in 

 all amniotic vertebrates (Peter). In 

 many animals possessing in high 

 degree the sense of smell (macros- 

 matic), the ojgan is well developed 

 and functions, serving possibly as an 

 accessory and outlying surface by 

 which the first olfactory impressions 

 are received (Seydel). 



In man the organ is represented 

 by a laterally compressed tubular 

 diverticulum, from 1.56 mm. in 

 length, that passes backward and 

 slightly upward to end blindly be- 

 neath the mucous membrane on each 

 side of the septum. The entrance 

 to the tube is a minute aperture 

 situated near the lower border of 

 the septum, above the anterior nasal 

 spine and the rudimentary vomerine 

 cartilage. The median wall of the 

 diverticulum is clothed with epithe- 

 lium composed of tall columnar cells 

 resembling those of the olfactory 

 region, but the characteristic olfac- 



torv Cells are wanting" The eoithe- Portion of frontal section through nasal fossae of kitten, showing 

 . . - 1 . < 1 1 organ of Jacobson. X 20. 



hum covering of the lateral wall 



corresponds to that of the respiratory region. In macrosmatic animals branches of 



the olfactory nerve are traceable to Jacobson's organ in which are found olfactory cells. 



PRACTICAL CONSIDERATIONS : THE NASAL CAVITIES. 



The nasal cavities have certain important clinical relationships which may be 

 classified as (i) physiological (a) respiratory, phonatory and olfactory ; (^) sexual ; 

 (2) topographical (a) the nasal chamber and the vestibule ; (3) the premaxillary, 

 maxillary, and palatal portions ; (c) the septum, and the turbinate bones. 



i. (a) The air passing out from the pharynx, being confined to the plane of 

 the posterior nares, is not carried up to the olfactory region, so that the odors on the 

 expired breath are not appreciated. When the communication between the respira- 

 tory and olfactory portions is cut off, as by swelling of the mucous membrane at 

 the region of union of these portions, loss of smell supervenes. Discharge which may 

 accumulate about the middle turbinate bone or in the upper portion of the vestibule 

 cannot be removed by the act of blowing the nose, for the reason above assigned that 

 the air of expiration cannot pass within the olfactory portion. The act of blowing 

 the nose, or the process of washing out the nose by a current thrown in from the 

 naso-pharynx, will wash out the inferior meatus with ease, provided the discharge is 

 not inspissated, and the parts of the floor of the nose are normal (Allen). An 

 abnormal width or patency of the respiratory portion of the fossa especially of the 

 inferior meatus due to imperfect development of the inferior turbinates, has 

 been thought (Lack), by diminishing the vis a tergo in blowing the nose and thus 

 favoring the retention and decomposition of the nasal mucus, to contribute to the 

 occurrence of atrophic rhinitis (ozaena). The value of the nose as an accessory 

 organ of phonation consists in its action as a resonating cavity which adds quality, 

 color and individuality to the voice. This function of the nose becomes strikingly 



