What is the organ of smell?

What it is

• The peripheral olfactory organ or organ of smell consists of two parts: an outer, the external nose, which projects from the center of the face; and an internal, the nasal cavity, which is divided by a septum into right and left nasal chambers. the External Nose (Nasus Externus; Outer Nose) —The external nose is pyramidal in form, and its upper angle or root is connected directly with the forehead; its free angle is termed the apex.
• Its base is perforated by two elliptical orifices, the nares, separated from each other by an antero-posterior septum, the columna. The margins of the nares are provided with a number of stiff hairs, or vibrissæ, 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 in the middle line, the dorsum nasi, the direction of which varies considerably in different individuals; the upper part of the dorsum is supported by the nasal bones, and is named the bridge. The lateral surface ends below in a rounded eminence, the ala nasi. Structure. —The frame-work of the external nose is composed of bones and cartilages; it is covered by the integument, and lined by mucous membrane.