THE XOSE. 



677 



hvoid bone, the individual fibres being attached in their course to the sub- 

 mucous and glandular structures. 



The inferior longitudinal fibres are formed by the Lingualis muscle, already 

 described (p. 339). 



The transverse fibres are placed between the two preceding layers ; they are 

 intermixed with a considerable quantity of adipose substance, and form the 

 chief part of the substance of the organ. They are attached internally to the 

 median fibrous septum; and, passing outwards, the posterior ones taking an 

 arched course, are inserted into the dorsurn and margins of the organ, inter- 

 secting the other muscular fibres. 



The arteries of the tongue are derived from the lingual, the facial, and ascend- 

 ing pharyngeal. 



The nerves of the tongue are three in number in each half: the gustatory 

 branch of the fifth, which is distributed to the papillae at the fore part and 

 sides of the tongue ; the lingual branch of the glosso-pharyngeal, which is 

 distributed to the mucous membrane at the base and side of the tongue, and to 

 the papillse circumvallata3 ; and the hypoglossal nerve, which is distributed to 

 the muscular substance of the tongue. The two former are nerves of common 

 sensation and of taste ; the latter is the motor nerve cf the tongue. 



THE NOSE. 



The Nose is the special organ of the sense of smell : by means of the peculiar 

 properties of its nerves, it protects the lungs from the inhalation of deleterious 

 gases, and assists the organ of taste in discriminating the properties of food. 



The organ of smell consists of two parts, one external, the nose ; the other 

 internal, the nasal fossa3. 



The nose is the more anterior and prominent part of the organ of smell. It 

 is of a triangular form, directed vertically downwards, and projects from the 

 centre of the face, immediately above the upper lip. Its summit, or root, is 

 connected directly with the forehead. Its inferior part, the base of the nose, 



Figs. 364, 365. Cartilages of the Nose. 



S itlt- Vie-w 



Lau-erLateraf *, 



'stamcid C, 



presents two elliptical orifices, the nostrils, separated from each other by an 

 antero-posterior septum, the columna. The margins of these orifices are pro- 

 vided with a number of stiff hairs, or vibrissse, which arrest the passage of 

 foreign substances carried with the current of air intended for respiration. The 

 lateral surfaces of the nose form, by their union, the dorsum, the direction of 



