Fig. 4. Segmental localization and reconstruction of reticulospinal neurons with contralateral axons adjacent to the M-axon in the mlf_d. (Ai) Whole mount of the hindbrain, with Lucifer Yellow filled M-axons (upper arrows) and one reticulospinal neuron located in r6 (lower arrow). The M-cell somata are not filled. Higher magnification of the same r6 reticulospinal neuron obtained after sectioning the hindbrain (Aii) and a camera lucida reconstruction of this neuron (Aiii). (Bi,Bii) reconstruction of two other r6 neurons from separate fish. In Aii-Aiii and Bi-Bii, the crossing axons of the reticulospinal neurons are labeled with asterisks, the midline is to the right and scale bars are 50 µm.