9 
Figiire 5. Cranium of Edmontosaurus, Cat. No. 2289; | natural size; inferior aspect. Als, 
alisphenoid; Bs, basisphenoid; Boc, basi-occipital ; bsp, process of basispbenoid; Exo, exoccipital; 
F, frontal; y, surface for jugal; L, lachrymal; Z. car. in, lower entrance of internal carotid artery; 
mx, surface for maxillary; N, nasal; occ, occipital condyle; Opot, opisthotic (paroccipital process); 
Orsp, orbitosphenoid; P, parietal; Pasp, parasphenoid; pmx, surface for upper limb of premaxillary; 
Pof, postfrontal; Prf, prefrontal; Prot, prootic; Psp, presphenoid; pt, surface for pterygoid; q, 
surface for quadrate; Sq, squamosal; sqc, squamosal cotylus; Soc, supra-occipital; stf, supra- 
temporal fenestra. 
