Authors conducted basic studies of endolymphatic flow induced by caloric stimulation using squirrel monkeys. Following results were as obtained. 1) Well defined relationship was found to exist between the onset of nystagmus and temperature difference between the ampulla and crus of the horizontal semicircular canal. 2) Endolymphatic flow on onset of nystagmus was 7.8 to 9.2 X 10-5cm/sec.
