The LT branch extends to the torus semicircularis. (a, b) As seen dorsally in whole-mount embryos, the LT projection courses anteriorly and laterally at a level slightly ventral to the ventral commissures, and turns abruptly upon reaching its target (see also Figures 7 and 12). In (a), the dotted line indicates the approximative plane of the vibratome section shown in (c-e). (c) In this section, the terminal arbor of the LT projection is seen to extend along the torus semicircularis, (d) which is easily delineated under Nomarski optics. (c, e) Fine fibers from the LT arbor extend into the torus.