1. Spontaneous activity and responses to simple tonal stimuli were studied in cochlear ganglion neurones of the starling. 2. Both regular and irregular spontaneous activity were recorded (Figs. I to 5). Non-auditory cells have their origin in the macula lagenae. Mean spontaneous rate for auditory cells (all irregularly spiking) was 45 spikes s-1. 3. In half the units having characteristic frequencies (CFs)
