This is the thick crest of bone that projects above the cribriform plate as if it were an extension of the perpendicular plate. It resembles the crest-like comb on the rooster's head. The crest is thickest near its base and tapers superiorly. Its anterior margin is more vertical than its gradual sloping posterior margin. It projects between the two cerebral hemispheres with the falx cerebri attaching to its posterior margin. At the base of the anterior border two small alae project forward to articulate with the frontal bone. A small gap remains between the two alae and their junction with the frontal bone forming a small foramen, the foramen caecum, in the articulated skull. This foramen is patent only in some adult skulls. When patent, it transmits a small vein from the nasal cavity to the superior sagittal venous sinus within the skull.

Crest is a term applied to a ridge of bone. The Latin term used for this is crista. Galli comes from the Latin term gallus meaning a cock or rooster. Early anatomists thought that this plate of bone resembled the comb of the rooster.