Anterior ethmoidal foramen

Lateral to either olfactory groove are the internal openings of the anterior and posterior ethmoidal foramina (or canals).

The anterior ethmoidal foramen, situated about the middle of the lateral margin of the olfactory groove, transmits the anterior ethmoidal vessels and the nasociliary nerve; the nerve runs in a groove along the lateral edge of the cribriform plate to the slit-like opening above mentioned.