. Bulletin - United States National Museum. Science. 16 BULLETIN 110, UNITED STATES NATIONAL MUSEUM. wliich meets the posterior border of the laclirymal. The rounded spur-like projec- tion of the frontal was received between the branches on the internal side of the bone. Its heavy vertically rounded posterior border forms the anterior boundary of the narrow but deep notch above the orbit. So far as I am aware the prefrontal bone has not before been recognized in the Theropodous dinosaur skull except in Tyrannosaurus, where it is much more reduced and occupies a more central position, barely re
. Bulletin - United States National Museum. Science. 16 BULLETIN 110, UNITED STATES NATIONAL MUSEUM. wliich meets the posterior border of the laclirymal. The rounded spur-like projec- tion of the frontal was received between the branches on the internal side of the bone. Its heavy vertically rounded posterior border forms the anterior boundary of the narrow but deep notch above the orbit. So far as I am aware the prefrontal bone has not before been recognized in the Theropodous dinosaur skull except in Tyrannosaurus, where it is much more reduced and occupies a more central position, barely reaching tiie nasals. Postfrordal + postorUtal {).—The right postfrontal remained firmly attached to the posterior portion of the skull, the left was found detached, so that the two bones give a very accurate conception of its form ami" relationships. It is a triradi- ate bone, with one short heavy process that extends inward and articulates with the frontal by a deep interlocking suture; a second slender, tapering, posteriorly directed process that is received in a deep lateral groove,on the anterior extension of the squa- mosal, these forming the upper temporal bar; the third, the longer one of the three, also a tapering process, extends downward and joins by a lapping suture the superior process of the jugal, thus forming the postorbital bar which separates the orbit from the infratemporal opening. This process, as in many of the Preden-. 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 perfectly resemble the original United States National Museum; Smithsonian Institution; United States. Dept. of the Interior. Washington : Smithsonian Institution Press, [etc. ]; for sale by the Supt. of Docs. , U. S. Govt Print. Off.
Size: 2239px × 1116px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
