The functional organization of the propus-dactylus organ in Cancer irroratus say

Abstract

1. 1. In the propus-dactylus organ of the crab, Cancer irroratus Say, neurons paired in the same scolopidium are sensitive to the same directional stimulus. 2. 2. The dendrites of relaxation-sensitive cells (RSC) are inserted into the dorsal side of the elastic strand, while those of elongation-sensitive cells (ESC) are inserted into a narrow band on the anterior side of the elastic strand. 3. 3. Small neurons inserted distally along the anterior side of the strand near the ventral edge are position sensitive. Their axons form a distinct bundle which exists near the elongation-sensitive cell insertions. 4. 4. Certain movement cells show position sensitivity. Those at the distal end of the strand are sensitive to the open arc region, while those at the proximal end are more sensitive to the closed arc region. 5. 5. Spikes are initiated in the region of the scolopidium.