102 University of California Publications in Zoology 



34-35. Anterior inferior alveolar foramen (Fig. 23): (A) always between splenial and 

 dentary, the coronoid may or may not contribute to its posterior margin; (B) entirely within 

 the dentary in some specimens (others A); (C) between splenial and coronoid. 



36. Labial process of coronoid (Fig. 24): (A) small; (B) intermediate; (C) large. 



37. Angular I (Fig. 25): (A) extends far up the labial surface of the mandible and is 

 largely visible in lateral view; (B) does not extend far up the labial surface of the mandible 

 and is barely visible in lateral view. 



38. Angular II: (A) wide posteriorly; (B) narrow posteriorly. 



39. Surangular (Fig. 26): (A) exposed laterally only about as far forward as the apex 

 of the coronoid or the anterior slope of this bone, and never anterior to the last dentary 

 tooth; (B) exposed laterally well anterior to the apex of the coronoid and often anterior to 

 the last dentary tooth. 



40. Lingual exposure of surangular between ventral processes of coronoid (Fig. 27): 

 (A) a dome-shaped portion exposed; (B) largely or completely covered by prearticular. 



41. Angular process of prearticular (Fig. 28): (A) increases substantially in relative 

 size during postembryonic ontogeny, becoming a prominent structure in adults; (B) 

 increases only slightly in relative size during postembryonic ontogeny, remaining relatively 

 small even in adults. 



42. Retroarticular process (Figs. 28, 29): (A) tympanic and medial crests converge 

 posteriorly to give the process a triangular outline in both juveniles and adults; (B) 

 tympanic and medial crests converge posteriorly in juveniles, but the posterior ends 

 separate during ontogeny so that the process assumes a quadrangular outline in adults. 



43-44. Modal number of premaxillary teeth (Table 3): (A) fewer than seven; (B) 

 seven; (C) more than seven. 



45. Crowns of premaxillary teeth: (A) lateral cusps small or absent; (B) lateral cusps 

 large. 



46. Crowns of posterior marginal teeth I (Fig. 30): (A) tricuspid; (B) four-cusped; (C) 

 polycuspate (5 to 10 cusps); (D) serrate. 



47. Crowns of tricuspid posterior marginal teeth II (Fig. 30): (A) individual lateral 

 cusps much smaller than apical cusp; (B) individual lateral cusps relatively large, subequal 

 to apical cusp in size. 



48. Pterygoid teeth I (Fig. 31): (A) entire row lies along the ventromedial edge of the 

 pterygoid adjacent to the pyriform recess; B) posterior portion of row displaced laterally. 



49. Pterygoid teeth II (Fig. 31): (A) entire row single throughout ontogeny; (B) 

 posterior portion of row doubles ontogenetically; (C) entire row doubles ontogenetically. 



50. Pterygoid teeth III (Fig. 31): (A) anterior portion of tooth patch present; (B) 

 absent (posterior end of suborbital fenestra used as reference point). 



51. Pterygoid teeth IV (Fig. 31): (A) usually present; (B) usually absent. 



52-53. Hyoid I (Fig. 33): (A) second ceratobranchials short, often less than two- 

 thirds the length of the first ceratobranchials; (B) intermediate, from two-thirds the length 

 of the first ceratobranchials to slightly longer than the first ceratobranchials; (C) long, much 

 longer than the first ceratobranchials. 



