The essential task of the nose is the optimal conditioning of inhaled air for gas exchange in the lungs. In the light of comparative studies concerning the anatomical structure of the nose men and animals, it is illustrated that the function of the human nose is essentially different from that of the animal. Investigations concerning the function of the nose and having competent evidential value man can only be achieved by studying the human nose itself. After a review of the previous investigations and their results, continuous and extensively irritation free measurement of the nasal mucosa with small thermistor probes which are inserted simultaneously into both lower meatus of the nose are described. Combined with the thermistor probes are phototransistors. For measuring the degree of swelling of the lower concha a coldlight-source is placed in the common meatus of the nose, without mucosa contact light transmission through the concha is measured by the phototransistor. The reaction of the nasal mucosa temperature and of the degree of swelling of the inferior nasal concha to caloric stimulation on one side and on both sides of the upper and lower extremity is investigated. The results of these investigations indicate a close reflex relationship between nasal mucosa and extremities. It is demonstrated that warm and cold stimulation on the one side of the lower extremity induces quick and intense reaction of the homolateral nose. Warm stimulation of the lower leg on both sides extends the reaction times of the nasal mucosa, while cold stimulation of both sides causes a distinct reduction of the reaction time. Cold stimulation on one side of the lower arm reduces the reaction time as compared with cold stimulation of lower leg. Further, it is demonstrated that the degrees of swelling are not joint absolutely with the change of temperature but can take there courses independently. Warm stimulation as well as cold stimulation cause, in a majority of cases, an immediate decrease in the degree of swelling. The corpus cavernosum reacts to thermocutaneous remote stimulation quicker than does the mucosa temperature.