The anatomy and adequate stimulation of a chordotonal organ in the antennae of a hermit crab

Abstract

1. 1. A chordotonal organ in the basal segment of the antennal flagellum of the hermit crab, Petrochirus californiensis, is described. 2. 2. Adequate stimulation is flexion or intrascolopidial compression of the dendrites. Stretch of the dendrites inhibits responses from the bipolar sensory cells. 3. 3. A theory for the adequate stimulation of the flagellar chordotonal organ is applied to periopod elastic strand stretch receptors. A mechanism that results in flexion of the dendrites in response to strand stretch or relaxation is proposed to account for the responses obtained from the other chordotonal organs. 4. 4. It is suggested that movement of responses, most position responses and responses that are intermediate could arise from a single type of cell, and would depend only on the physical arrangement of the dendrites within the strand.