The ethmoidal notch separates the two orbital plates; it is quadrilateral, and filled, in the articulated skull, by the cribriform plate of the ethmoid.

Ethmoidal notch
Frontal bone. Inner surface (ethmoidal notch visible at center)
Details
Identifiers
Latin	Incisura ethmoidalis ossis frontalis
TA98	A02.1.03.028
TA2	548
FMA	57388
Anatomical terms of bone [edit on Wikidata]

The margins of the notch present several half-cells which, when united with corresponding half-cells on the upper surface of the ethmoid, complete the ethmoidal sinuses.