FMRF AMIDE-LIKE-IMMUNOREACTIVE PRIMARY SENSORY NEURONS IN THE OLFACTORY SYSTEM OF THE TERRESTRIAL MOLLUSK, LIMAX-MARGINATUS

The distribution of FMRF amide-like immunoreactivity was investigated in the olfactory organs in the tentacle tip of the terrestrial slug, L imax marginatus. Approximately 0.7% of the neurons in the lobules of t he tentacle ganglia demonstrated FMRF amide-like immunoreactivity. Mos t of the FMRF amide-like-immunoreactive somata lay at superficial posi tions within the lobules, and dendritic processes extended to the oute r surface of the sensory epithelium, whereas the axons traveled toward the cerebral ganglion through the ventral part of the tentacle nerve. From their morphological features, FMRF amide-like-immunoreactive cel ls were considered to be primary sensory neurons.