Figure 9. Stereopairs and line drawings of posterior portion of skull of Pachyrhachis problematicus (HUJ-PAL 3659), from computer reconstructed surface model derived from CT data in (9.1) dorsal and (9.2) ventral views. Abbreviations: atn, atlas neural arch; ax, axis vertebra; bs, basisphenoid; bo, basioccipital; cor, coronoid; ex, exoccipital; p, parietal; pt, pterygoid; q, quadrate; s, stapes; so, supraoccipital; st, supratemporal; V3, 3^rd cervical vertebra.