Abstract
The presence of ventral neurons in the seventh abdominal ganglion of the locust Locusta migratoria, with properties similar to dorsal unpaired median neurons, are reported. These cells resemble dorsal unpaired median neurons in that they possess similar morphological and neurophysiological properties, show an affinity for neutral red, and contain octopamine. Octopamine-containing neurons of the unpaired median type are therefore not confined to the dorsal surface.