For example, the Forum recognized that the hypoglossal nucleus had been incorrectly identified as the nucleus intermedius in the Karten and Hodos (1967) pigeon brain atlas, and what was identified as the hypoglossal nucleus in that atlas should instead be called the supraspinal nucleus. 
Motoneurons innervating these muscles are located in the supraspinal nucleus and ventral horn of the rostral cervical cord.
The supraspinal nucleus (SSp) in the mallard, which lies in the rostral spinal cord and caudal brainstem, is a motor nucleus that forms the rostral continuation of the ventral horn.
Caudally, filled cells were located in the parvocellular, magnocellular, dorsal, and ventral reticular nuclei, the supraspinal nucleus, and the upper cervical ventral horn.
Labeled motoneurons were found in the supraspinal nucleus of the lower brainstem and in the ventral horn of the upper cervical cord.
Comparison between motoneurons located in the supraspinal nucleus of the brainstem and motoneurons in the ventral horn of the upper spinal cord showed that dendrites of motoneurons in the first cell group branch more often than those of neurons in the latter group.
The hypobranchial MNs formed a sequence of cell columns extending caudally from the hypoglossal nucleus, via the supraspinal nucleus, to the medial and then the ventrolateral subnuclei of the ventral horn of C1 to C3. The infrahyoid MNs were located in the supraspinal nucleus and the ventral horn, and their axons passed through the first to third cervical nerves.
Labeled cells were found ipsilaterally in the supraspinal nucleus, nucleus ambiguus (including nucleus retrofacialis) and nucleus intercalatus of all animals, in the parasympathetic nucleus of X (dorsal vagal efferent nucleus) of 6 animals, and in the hypoglossal nucleus of 4 animals. Small numbers of HRP-labeled cells were found contralaterally in the supraspinal nucleus of all animals, and in the rostral nucleus ambiguus, in the nucleus intercalatus and the parasympathetic nucleus of X of fewer animals.
Efferent projections of MVN are to: (1) the ipsilateral supraspinal nucleus (SSN), and (2) the contralateral central cervical nucleus (CCN), MVN, SVN, cell group 'y', the rostroventral region of LVN, the trochlear nucleus (TN) and the INC.
All their axons passed through the first cervical nerve, and thus, the rostral portion of the thyrohyoid motoneuron column, which appears to be part of the hypoglossal nucleus, is not included in this nucleus but constitutes the supraspinal nucleus, which connects the hypoglossal nucleus to the ventral horn motoneuron group.
First, such axons project to the supraspinal nucleus of the caudal medulla; this nucleus is known to project to the upper cervical spinal cord gray.
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