The ethmoidal notch separates the two orbital plates; it is quadrilateral, and filled, in the articulated skull, by the cribriform plate of the ethmoid.
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.
This article incorporates text in the public domain from page 137 of the 20th edition of Gray's Anatomy (1918)
