Computer-assisted morphometrics were used to characterize mature somatodendritic architecture in Golgi-stained neurons of the entopeduncular nucleus (EN) of the adult cat. Only one form of adult EN neuron was apparent and characterized by common features including: relatively large conical somata, long aspiny and moderately branched dendrites and discoid to spherical dendritic fields oriented randomly within the EN. These results indicate that feline EN neurons have some properties in common with large neurons of the primate medial pallidal segment.