. Breviora. 8 BREVIORA No. 143 tends to be subaerodont. (2) D. colombiana has fifteen dentary teeth, D. paraguayensis has ten {fide Amaral) and D. guianensis twelve. (3) The anterior teeth, as far as they are preserved, are less bulbous than in the Recent species. (4) The occlusal outline of the tooth crowns is round or suboval in the fossil and sub- oval or subrhoml)ic in D. guianensis. (5) The crown surface of the molariform teeth is more flattened, and the dorsoventral compression of the entire tooth is less in the fossil. The referred skeletal elements are somewhat larger than would be exp
. Breviora. 8 BREVIORA No. 143 tends to be subaerodont. (2) D. colombiana has fifteen dentary teeth, D. paraguayensis has ten {fide Amaral) and D. guianensis twelve. (3) The anterior teeth, as far as they are preserved, are less bulbous than in the Recent species. (4) The occlusal outline of the tooth crowns is round or suboval in the fossil and sub- oval or subrhoml)ic in D. guianensis. (5) The crown surface of the molariform teeth is more flattened, and the dorsoventral compression of the entire tooth is less in the fossil. The referred skeletal elements are somewhat larger than would be expected for a modern Dracaena with a dentary the size of D. colombiana, as the appendicular skeleton is relatively small in the Recent species. If correctly referred, the skeletal elements perhaps came from a larger individual. The sacrum and first caudal vertebra are characteristically teiid, having a perfectly round cup and ball, and strongly developed zygo- sphene-zygantrum. They resemble comparable bones of Recent Dracaena more than those of Recent Tupinamhis. The femur has the deep patellar groove seen in many teiids and resembles Dracaena in having more separation between head and tro- chanter major than that seen in Tupinamhis. The lack of a pronounced fossa posterior to the condyles resembles the condi- tion in Dracaena. Some of these bones may be referable to the Tupinamhis described above, but on the basis of present comparisons, all are referred to Dracaena colomhiana. Family IGUANIDAE Unidentified Genus and Species A fragmentary left dentary of an iguanid, U. C. no. 39644, from U. C. loc. V-4517, Monkey Unit, shows some similarity to the living Polychrus, but lacks the vertical wrinkling of the. Figure 5. Iguanidae, unidentified genus and species, U. C. no. 39644, Miocene, Colombia, left dentary, broken anteroposteriorly, x Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and a
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