 The optic tract grows from the retina to the optic tectum , as dorsal and ventral are inverted in the anterior head region, the tracts grow at first to the ventral side  to meet in the midline to form a chiasma.
<clarity>  The optic tract grows from the retina to the optic tectum , as dorsal and ventral are inverted in the anterior head region, the tracts grow at first to the ventral side  to meet in the midline to form a chiasma.
 The optic tract grows from the retina to the optic tectum , as dorsal and ventral are inverted in the anterior head region, the tracts grow at first toward the ventral side to meet in the midline to form a chiasma.