The responses and morphology of nine sound-sensitive interneurons are described in the cricket Teleogryllus oceanicus. Each of the neurons receives direction-specific input in the prothoracic ganglion, and each projects at least one interganglionic axon. Five of the neurons respond best to high frequencies ($>$10 kHz); four are most sensitive to low frequencies (3-10 kHz). Responsiveness to model calling songs was examined in addition to testing sensitivity to wind and light. Anatomical observations reveal that seven of the neurons receive auditory input via polysynaptic pathways, and that at least five of the neurons have morphology consistent with them providing input to mesothoracic motor neurons which are involved in behavioral responses to sound. Correlations between structure, topographic organization, and spectral sensitivity were found. The structure of one previously identified, auditory neuron was examined and found to change during late post-embryonic life. This represents a novel developmental pattern.

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