Identification of cardio-inhibitory neurons in the thoracic ganglion of the isopod crustacean Bathynomus doederleini.

We identified cell bodies of a pair of the cardio-inhibitory (CI) neurons in the first thoracic ganglion (TG1) of Bathynomus doederleini. Each of the cell bodies gives rise to a single axon, which runs into the contralateral hemiganglion of TG1 via the commissure and runs to the heart via the fourth root as CI axon. Some fine processes arise from the axon at two points in both hemiganglia.