Table 1. Dimensions of simocetid skulls and mandible.

Measurements (in mm) of Simocetidae gen. et sp. A (LACM 124104), Olympicetus thalassodon gen. et sp. nov. (LACM 158720) and Olympicetus sp. 1 (LACM 124105). Modified after Perrin (1975).

	LACM 124104	LACM 158720	LACM 124105
Width of rostrum at base	–	135	93+
Width of rostrum at 60 mm anterior to line across hindmost limits of antorbital notches	–	105	–
Greatest preorbital width (width across preorbital processes)	–	153	136
Greatest postorbital width	–	187	150e
Mid-orbital width	–	151	140e
Maximum width of external nares	–	33	–
Greatest width across zygomatic processes of squamosals	322e	220	186e
Greatest width of premaxillae	–	83	–
Greatest parietal width within temporal fossae	154	135	100
Vertical external height of braincase from midline of basisphenoid to summit of supraoccipital, but not including external occipital crest	135	112	–
Greatest length of left temporal fossa, measured to external margin of raised suture	–	99	–
Greatest width of left temporal fossa at right angles to greatest length	–	51	–
Major diameter of left temporal fossa proper	–	111	–
Minor diameter of left temporal fossa proper	59	45	–
Distance from foremost end of junction between nasals to hindmost point of margin of supraoccipital crest	–	143e	–
Length of orbit –from ventral apex of preorbital process of frontal to apex of postorbital process	–	55	40+
Length of antorbital process of lacrimal	–	18	12
Greatest length of left pterygoid	132	79	–
Maximum width across occipital condyles	92	78	–
Height of foramen magnum	33	35	–
Width of foramen magnum	39	32	–
Cranial length –antorbital notch to condyles	–	211	165+
Greatest length of left mandibular ramus (as preserved)	–	251+	–
Greatest length of right mandibular ramus (as preserved)	–	244+	–
Maximum height at mandibular condyle	–	54	–

Notes.

Abbreviations

e

estimate; + = measurement on incomplete element