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University of California Publications in Zoology 



tlV 



FIG. 44. Right tarsal region of Brachylophus fasciatus. Scale equals 0.5 cm. Abbreviations: a, 

 astragalus; c, calcaneum; f, fibula; ml-V, metatarsals 1-5; t, tibia; till and tlV, distal tarsals 3 and 4. 



dermal skull roof in certain iguanids, are unknown in iguanids other than Amblyrhynchus 

 (Etheridge and de Queiroz, 1988), and their presence is thus considered derived within 

 iguanines. Although Conolophus has enlarged, conical head scales overlying the nasal, 

 prefrontal, and frontal bones similar to, yet smaller than, those seen in Amblyrhynchus, I 

 have never observed osteoderms in Conolophus. The osteoderms of Amblyrhynchus are 

 easily removed along with the skin, judging from their absence in most skeletal 

 preparations of Amblyrhynchus, and it is therefore possible that Conolophus also 

 possesses osteoderms. I will assume that osteoderms are absent in Conolophus until their 

 presence is demonstrated. 



