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University of California Publications in Zoology 



FIG. 30. Lingual views of left maxillary teeth of (A) Conolophus pallidas (RE 1382), (B) Sauromalus 

 varius (RE 539), (C) Iguana iguana (JMS 1028), (D) Basiliscus plumifrons (RE 427), and (E) 

 Amblyrhynchus cristatus (RE 1387), showing differences in cuspation. Scale equals 1 mm. 



Increase in cuspation is accompanied by a difference in the morphology of the maxillary 

 versus dentary teeth: maxillary teeth bear more cusps along their anterior edges, while 

 cuspation of the dentary teeth is more or less symmetrical (Avery and Tanner, 1964:Fig. 

 3). Within the tooth row of a single organism, increase in cuspation appears to result from 

 addition of cusps to the anterior and posterior edges of the crowns. 



Still greater cuspation occurs in Iguana, reaching an extreme in /. iguana. In this genus 

 the teeth possess a large number of small cusps, giving them a serrated cutting edge (Fig. 

 30C). The small cusps are difficult to count, especially when worn, but the maximum 

 number is greater than 15 in /. delicatissima and greater than 20 in /. iguana. Cuspation 

 increases both ontogenetically and from anterior to posterior in a single tooth row by two 

 mechanisms: addition of cusps and subdivision of the fields of preexisting ones. The 

 actual cusps of fully formed teeth are not subdivided, though their fields appear to be when 

 teeth are compared with their replacements; it is, of course, impossible to have actual 

 subdivision of cusps from one tooth to the next. Because cuspation increases 

 ontogenetically, the teeth of young Iguana have about as many cusps as do those of some 



