[Structure-functional features of peripheral nerve elements in oligochaetes].

Histological investigation of the peripheral nervous elements in the earthworm indicates that in 3-projection neurons which are found along the I and III segmentary nerves, one of the projections terminates between epithelial cells, whereas the other produces many ramifications which form multiple terminations in the longitudinal muscles. These polyvalent neurons presumably serve as a morphological basis for the peripheral axon-reflex in the earthworm.