抄録
The activity of the olfactory epithelium was studied in the frog and the toad by means of micro-and macro-electrodes.
1) Resting potentials of 4 to 16 mV (9.5 mV on the average) were obtained when a micro-electrode impaled the epithelium.
2) In response to olfactory stimulation, the slow potentials were simultaneously recorded by means of micro-and macro-electrodes. They were found not only at the onset of stimulation, but also at the cessation. Thus, three types, on-, on-offand off-types of responses were found.
3) The stability of the response types was studied by repetitive application of the same odour. It was found that the response types of the cells in the olfactory epithelium are not stable in the frog and the toad.
4) The response types obtained by micro-electrode do not always coincide with those recorded by macro-electrode. Moreover, the shapes and the types of the responses obtained by two micro-electrodes set as close as possible are not always the same. It was therefore concluded that there are two or three kinds of elements in the olfactory epithelium which produce the on-and the off-, or the on-, the on-off-and the off-responses.
5) An electro-positive off-response rarely appeared after a normal electro-negative on-response. It coincides with the off-response found in a kind of fish.
