Figure 4 - Morphology of the main generator source. Fluorescence microscope photograph and camera-lucida drawing of Lucifer Yellow-CH-filled images. R, Radial dimensional view; WM, whole-mounting preparation; A1, afferent process in the first nerve of the stimulated (left) side of this preparation; E1, efferent process in the first nerve of the recording (right) side of this preparation; E3, efferent process in the third nerve of the recording (right) side of this preparation; V, varicosities in the central region of these identified neurons; M-1, presynaptic neuron; M-2, postsynaptic neuron. Two longitudinal bundles of processes representing these two neurons are also visible in the upper middle region of V. AP, Anteroposterior view of the same preparation at a level near V. Some of the branches extend dorsoventrally and are not detectable in the R view above. Calibration: 100 Ám for all figures.