Figure 1.

Sound interactions in the cricket auditory system. The tympana are located on the tibia of the prothoracic legs. Sound from different inputs may propagate through air-filled tracheae and act on the interior tympanum surface by linear superposition. Red arrows indicate direct, external sounds at the four inputs. Internal transmissions from spiracles to ipsi- and contralateral tympana are given in green and blue; solid lines for ipsilateral transmissions and dashed lines for contralateral transmissions. Internal propagation from the contralateral tympanum is presumably negligible [23] and omitted in the diagram. Contralateral transmissions include the action of the medial septum, located centrally in the transverse acoustic vesicle.