SUMMARY1. Recording the suimmated electrical response from the human chorda tympani in the middle ear provides data for a quantitative study of the relation between the neural activity and the strength of the stimulus applied to the tongue which can be compared with the relation between the subjective estimation and the stimulus strength.2. Full comparative data obtained from two patients showed a very high correlation between the functions describing the subjective and the neural response in relation to the strength of citric acid and sucrose solutions applied to the tongue. In a third patient the same high correlation was obtained for NaCl and citric acid.3. The good agreement between the individual neurophysiological experiments and the psychophysical group experiment favours the view that a fundamental congruity is found between neural activity and perceptual intensity.

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Electrophysiological studies of thermal and taste reception in chickens and pigeons. Acta physiol. scand. 1959. 46. 133-151. -The impulse traffic in thermal and taste nerve fibres from the tongue of chickens and pigeons were analyzed while applying adequate stimuli to the tongue. Receptors were found in the tongue and pharynx which respond, in general, like those found in mammals. The thermal and taste receptors discharge through two peripheral branches of the 9th nerve only. In the chicken positive responses from the nerves followed the application of distilled water, salt, glycerine, ethylene glycol, quinine and acetic acid t o the tongue but not of sucrose and saccharine. The taste responses in the pigeon's nerves were similar with the exception that no responses were observed to quinine and that 50 per cent of the pigeons responded positively to saccharine although sucrose was ineffective. In both species large number of "cold fibres" were observed while warming the tongue gave no response iintil the temperature was

a Wellcome Research Travel Grant. of Veterinary Anatomy, University of Minnesota, St. Paul 1. PFAFFMANN, C., Gustatory afferent impulses. J. cell. wmp. PhysioE. 1941. 17. 243 ZOTTERMAN, Y., Specific action potentials in the lingual nerve of cat. Skund. Arch. ZOTTERMAN, Y. Species differences in the water taste. dcla physwl. seand. 1966. ZOTTBHJIAX, Y. Studies in the nervous mechanism of taste. E'zp. Cell. Res. 1958. P h y d . 1936. 75. 105-119. 37. 60-70.Snppl. 5. p. 620--526.

Summary. The carotid bifurcation and carotid gland are the site of origin of stretch receptor fibres which join the glossopharyngeal nerve. These fibres behave in a manner similar to those of the carotid sinus nerve of mammals, as shown by their impulse activity under conditions of arterial distension. The pulmo‐cutaneous trunk possesses stretch receptor fibres which join the laryngeal branch of the vagus. The possible function of these fibres is discussed. The pulmonary branch of the vagus contains fibres which originate from stretch receptors in the lung tissue. Inflation of the lung causes an increasing discharge of such fibres. It is suggested that the development of this mechanism is related to the mode of respiration displayed by the frog.