. A diapsid reptile from the Pennsylvanian of Kansas. Reptiles, Fossil -- Kansas; Paleontology -- Pennsylvanian; Paleontology -- Kansas. 36 SPECIAL PUBLICATION MUSEUM OF NATURAL HISTORY NO. 7 teriorly along the series. Zygapophyses persist beyond the fortieth caudal as simple anterior and posterior projections above the spool-like centra. They are, however, definitely lost by the fiftieth caudal. Associated with the five anteriormost cau- dal vertebrae but not preserved in position, are two chevron bones. The first chevron, in KUVP 336()6c, probably fits between the third and fourth caudals. A
. A diapsid reptile from the Pennsylvanian of Kansas. Reptiles, Fossil -- Kansas; Paleontology -- Pennsylvanian; Paleontology -- Kansas. 36 SPECIAL PUBLICATION MUSEUM OF NATURAL HISTORY NO. 7 teriorly along the series. Zygapophyses persist beyond the fortieth caudal as simple anterior and posterior projections above the spool-like centra. They are, however, definitely lost by the fiftieth caudal. Associated with the five anteriormost cau- dal vertebrae but not preserved in position, are two chevron bones. The first chevron, in KUVP 336()6c, probably fits between the third and fourth caudals. As seen in several speci- mens, they continue posteriorly at least as far as the fortieth caudal vertebra. They are apparently outgrowths of the intercentra and consist of a crescentic intercentral portion, and two thin ventral arms that converge dis- tally to enclose a vertically elongate foramen. The ventral projection is "Y"-shaped in pos- terior view. The first chevron appears to be small and delicately built. The second is much larger, with a long ventral projection beyond the foramen. As expected, the chevrons de- crease in length posteriorly, albeit gradually. Ribs .\s in all known primitive reptiles, ribs are present on every vertebra from the atlas to, and including, the proximal caudal vertebrae. The head of most ribs includes capitular and tubercular portions, but these vary consider-. FiG. 16.—Pctrolacosaunts kanxctisis Lane. Ribs, all X 1-5. (A-B) Atlanta! and axial ribs in lateral view, KUVP 9951 and 33604. (C) Ventrolateral view of fifth rib, KUVP 9956. (D) Medial view of sixUi (cerv- ical) rib, KUVP 9956. (E) Medial view of .seventh (first dorsal) rib, KUVP 9956. (F) Anterodorsal view of eighth rib, slightly enished, KUVP 9956. (G) Anterior view of rib 15 slightly crushed, KUVP 9951. (H) Proximal ends of anterior dorsal ribs 9-11, KUVP 9956. (I) Posterior dorsal ribs 23 and 25, KUVP 33606b. (J) Ventral view of first sacral rib and lateral view of firs
Size: 1510px × 1655px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbi, booksubjectpaleontologykansas
