We know this section passes through the caudal medulla because the central canal has not yet opened into the fourth ventricle and the inferior olive is not yet prominent. Pyramidal tract axons, originating in the ipsilateral cerebral cortex, are descending through the pyramids; the majority will decussate, just caudal to this section, in the pyramidal decussation to enter the lateral corticospinal tract. Most of the axons ascending in the fasciculus gracilis have now terminated in the nucleus gracilis. Second order neurons in the nucleus are sending their axons across the midline, as internal arcuate fibers, to form the most ventral part of the medial lemniscus.The nucleus cuneatus lies slightly rostral to the nucleus gracilis and is only partially visible; some axons of the fasciculus cuneatus have terminated in the nucleus while others will do so at a more rostral level. Axons of the spinal tract of the trigeminal nerve (V), having their cell bodies in the trigeminal (semilunar) ganglion are descending into the cervical cord; at this level some axons peel off to terminate on second order neruons in the nucleus of the tract. The dorsal spinocerebellar, conveying information from the ipsilateral lower extremity to the cerebellum, lies just superficial to the spinal tract of V.