Fig. 3.

Cropped CT slices and line drawings of selected midline and coronal sutures in the Permian terrestrial tetrapod Phonerpeton and their positions in the skull roof. The white and black arrows indicate the ecto- and endocranial ends of each suture in cross-section. [Scale bars: 1 mm (suture) and 1 cm (skull).] The colored line across the top of each CT image indicates the position of that slice in the skull. Slices whose positions are shown in black on the dorsal reconstruction of Phonerpeton were measured in this study but are not figured here. The CT slices were obtained from Phonerpeton specimen MCZ 1414. Note the obvious shape change within the IPP suture. The dorsal reconstruction at left has been modified from the literature (24). Fr, frontal; Pa, parietal; PPa, postparietal; Na, nasal; R NF, right nasofrontal; R FP, right frontoparietal.