ABSTRACT A micro method, based on Stoke’s law corrected for the influence of adjacent walls, if used for the determination of the absolute viscosity of the pike’s endolymph. Samples of maximally 19 μl were used. The absolute viscosity has an average value of 1·20 ±0·08 cP at 23 °C for ten individual pike labyrinths. The values obtained are compared to those measured by a micro-rolling-sphere viscometer. The absolute values determined by both methods agree within the limits of error. The values obtained for the pike’s endolymph agree with those obtained for other species, if the temperature-dependence of the viscosity of water is taken into account. Though the semicircular canals in mammals are smaller than those in pike of equal body mass, they appear equally sensitive, if the temperature effect on the endolymph viscosity is taken into account.