the embryos shared in common : holoprosencephaly , arhinencephaly sensu stricto ( absence of olfactory nerve fibers , bulbs , and tracts ) , presence of a proboscis , synophthalmia with two lens vesicles , a retarded telencephalic wall , absence of the mediobasal part of the telencephalon ( the future septal area and the commissural plate : future anterior commissure and corpus callosum ) , irregularity of the diencephalon , mensural changes in the brain , absence of the rostral part of the notochord and consequent cranial defects , and small ganglia of the cranial nerves .
C0010090
corpus callosum
C0006104
brain