The authors studied the ultrastructure of axon processes in simple sensory corpuscles, Herbst and Pacinian corpuscles. They give a description of their shape, topographical localization and relation to organelles. They focused their attention to the incidence of various kinds of vesicles in the processes and at their bases, and the incidence and localization of of mitochondria. The most frequently occurring vesicles are those of medium electron density (clear vesicles), in small numbers there are also dense core vesicles and coated vesicles. The incidence of vesicles is predominantly polarized, i.e. they are situated at the bases of axon processes, opposite the so-called clefts of the inner core. In sporadic cases reach into the processes besides clear vesicles also mitochondria. Direct connection between axon processes and inner core lamellae was not observed. The authors are considering the possible importance of these processes in the transmission of stimuli to the axon. They are of the opinion that further studies are necessary to specify the morpho-physiological relations inside sensory corpuscles.