NeuroFIG 12: Commissures take medial or lateral routes.
Fibers traveling circumferentially within the two sides of the NR are examples of medially situated commissures. They are separated from the central muscle plate by the basal lamina of the muscle arms (orange ring). Posterior to the head, body commissures travel circumferentially along a lateral route, sandwiched between the hypodermis and the muscle, and are separated from the muscle by a basal lamina (orange lines).
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