. The Ceratopsia. Ceratopsia. TRICEKATOPS HORRIDUS. 121 The anatomy of the occipital region may be well seen from behind, as shown in fig. 107. The frill is for the most part wanting and the large hemispherical occipital condyle appears in the center, which gives origin above to the elongated exoccipital processes, greatly expanded distally and below to the short, stout basioccipital processes, while just in front of these may be seen only the extremities of the basisphenoid processes resting against the broad plates of the pterygoids, which diverge and give rise below to two processes, the br
. The Ceratopsia. Ceratopsia. TRICEKATOPS HORRIDUS. 121 The anatomy of the occipital region may be well seen from behind, as shown in fig. 107. The frill is for the most part wanting and the large hemispherical occipital condyle appears in the center, which gives origin above to the elongated exoccipital processes, greatly expanded distally and below to the short, stout basioccipital processes, while just in front of these may be seen only the extremities of the basisphenoid processes resting against the broad plates of the pterygoids, which diverge and give rise below to two processes, the broader and thinner of which gives support to the quadrate from within, while the longer and more slender passes downward and forward to meet the inferior branch of the maxillary. Above the occipital. KlG. 107.—Posterior view of type of Trircratops horridus. No. 1X3), Yule Museum. Drawn under Professor Marsh's supervision, bo Basioccipital; rxo, exoccipital; fm, foramen magnum; pa, parietal; /</</, pterygoid; 714, quadrate; so, supraoccipital; soli, supra- orbital horn core; .57, squamosal. One-eighth natural size. condyle is the foramen magnum, situated entirely within the exoccipitals. Above this the posterior surface of the exoccipitals shows two deep pockets or cavities situated one on either side of a strong, vertical, median bar which expands somewhat just below the suture for the supraoccipital. Laterally and superiorly the exoccipitals articulate with the squamosals. The supraorbital horn cores appear exceedingly massive. The rostral bone is also very heavy and not so sharp along its infero-anterior border as in most other species where (.bat element is known. The nasal horn is very broad at the base and quite short and blunt. The jugals, quadratojugals, and quadrates appear as Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not
Size: 1563px × 1598px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisherwashingtongovtprin
