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Skeletal reconstruction of Yuxisaurus kopchicki showing some of the main preserved elements from the holotype (highlighted in blue), with details of the skull bones (A), cervical vertebrae (B), dorsal vertebrae (C), left scapula (D), right humerus (E), and left femur (F). Scale bars equal 5 cm (A–C) or 10 cm (D–F). The facial region and distal scapula are mirrored. Osteoderms have been omitted for convenience.

skull restoration of Russellosaurus

Angulomastacator skull reconstruction with known elements in white. Scale bar 20 cm.

Skull of Banji long. The horizontal line projected through the posterodorsal corner of the antorbital fenestra is parallel to the line linking the articular end of the quadrate and the ventral margin of the premaxillae.

Fig. 2. Selected cranial elements of Bicentenaria argentina nov. gen. et nov. sp. A, left lateral view of preserved caudal half of skull and jaws; B, right lateral view of preserved caudal half of skull and jaws; C, left quadrate and lower jaw in caudal view; D, fragmentary premaxillae with teeth in left lateral view; E, fragmentary left maxilla with tooth in lateral view. Abbreviations: an, angular; antf, antorbital fossa; art, articular; bs, basipterygoid process of basisphenoid; ch, notch for the chorda tympanica; gl, glenoid fossa; j, jugal; lc, lateral condyle of quadrate; lr, longitudinal ridge; ect, ectopterygoid; prar, right prearticular; pral, left prearticular; ptq, pterygoid ramus of quadrate; q, quadrate; qj, quadratojugal; sanl, left surangular; sanr, right surangular; rart, retroarticular process; t, tooth. Scale bars = 1 centimeter.

Dinosaur National Monument is a United States National Monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green and Yampa Rivers. Although most of the monument area is in Moffat County, Colorado, the Dinosaur Quarry is located in Utah just to the north of the town of Jensen, Utah. The nearest communities are Jensen, Utah, and Dinosaur, Colorado. The park contains over 800 paleontological sites and has fossils of dinosaurs including Allosaurus, Deinonychus, Abydosaurus (a nearly complete skull, lower jaws and first four neck vertebrae of the specimen DINO 16488 found here at the base of the Mussentuchit Member of the Cedar Mountain Formation is the holotype for the description) and various long-neck, long-tail sauropods. It was declared a National Monument on October 4, 1915. The rock layer enclosing the fossils is a sandstone and conglomerate bed of alluvial or river bed origin known as the Morrison Formation from the Jurassic Period some 150 million years old. The dinosaurs and other ancient animals were carried by the river system which eventually entombed their remains in Utah. The pile of sediments were later buried and lithified into solid rock. The layers of rock were later uplifted and tilted to their present angle by the mountain building forces that formed the Uintas during the Laramide orogeny. The relentless forces of erosion exposed the layers at the surface to be found by paleontologists. The dinosaur fossil beds (bone beds) were discovered in 1909 by Earl Douglass, a paleontologist working and collecting for the Carnegie Museum of Natural History. He and his crews excavated thousands of fossils and shipped them back to the museum in Pittsburgh, Pennsylvania for study and display. President Woodrow Wilson proclaimed the dinosaur beds as Dinosaur National Monument in 1915. The monument boundaries were expanded in 1938 from the original 80-acre (320,000 m2) tract surrounding the dinosaur quarry in Utah, to its present extent of over 200,000 acres (800 km²) in Utah and Colorado, encompassing the spectacular river canyons of the Green and Yampa. Though lesser-known than the fossil beds, the petroglyphs in Dinosaur National Monument are another treasure the monument holds. Due to problems with vandals, many of the sites are not listed on area maps. The "Wall of Bones" located within the Dinosaur Quarry building in the park consists of a steeply tilted (67° from horizontal) rock layer which contains hundreds of dinosaur fossils. The enclosing rock has been chipped away to reveal the fossil bones intact for public viewing. In July 2006, the Quarry Visitor Center was closed due to structural problems that since 1957 had plagued the building because it was built on unstable clay. The decision was made to build a new facility elsewhere in the monument to house the visitor center and administrative functions, making it easier to resolve the structural problems of the quarry building while still retaining a portion of the historic Mission 66 era exhibit hall. It was announced in April 2009 that Dinosaur National Monument would receive $13.1 million to refurbish and reopen the gallery as part of the Obama administration's $750 billion stimulus plan. The Park Service successfully rebuilt the Quarry Exhibit Hall, supporting its weight on 70-foot steel micropile columns that extend to the bedrock below the unstable clay. The Dinosaur Quarry was reopened in Fall 2011. en.wikipedia.org/wiki/Dinosaur_National_Monument en.wikipedia.org/wiki/Wikipedia:Text_of_Creative_Commons_...

Photographs of the skull of BP/1/4779. (A) Right lateral view. (B) Dorsal view. (C) Left lateral view. Scale bar represents 10 mm. Photographs by Kimberley E.J. Chapelle.

Skull of the new basal sauropodomorph Leyesaurus marayensis (PVSJ 706). Photograph of the skull (A) and interpretative drawing (B) in lateral view. Dark grey color represents matrix and light grey color represents foraminae. Abbreviations: a, angular; aoF, antorbital fenestra; aoFo; antorbital fossa; Apmx, ascending process of the maxilla; d, dentary; f, frontal; itF, infratemporal fenestra; j, jugal; l, lacrimal; laoFo; lacrimal antorbital fossa; mF, mandibular fenestra; mx, maxilla; n, nasal; O, orbit; p, parietal; pf, prefrontal; pm, premaxilla; po, postorbital; rug, platform-like rugosities; q, quadrate; qj, quadratejugal; Rmx, ridge of the ascending process of the maxilla; sa, surangular; snf, subnarial foramen. Scale bar equals 1cm.

Life restoration of the Triassic ichthyosaur Callawayia neoscapularis. Three specimens of this ichthyosaur are known, the holotype, ROM 41993, and two referred specimens, TMP 94.380.11 and 94.382.2. The skull is primarily based on ROM 41993, cross-checked against TMP 94.380.11 and TMP 94.382.2. The vertebral column is based primarily on TMP 94.382.2 as it is the most complete of these specimens, while the ribs were based on ROM 41993. The forelimbs were mainly based on those of ROM 41993, with TMP 94.380.11 used to determine their breadth. The hindlimbs were based on TMP 94.380.11, especially the more complete right hindlimb. ROM 41993 was cross-scaled with TMP 94.380.11 by the dimensions of the forelimb epipodials, which produced similar vertebral dimensions. The two TMP specimens were cross-scaled based on femoral length, also producing similar vertebral dimensions. Nicholls & Manabe (2001) stated that no wedge-shaped caudal centra supporting a tailbend were found and that there was no evidence of a bend being present, though considered that they might have existed in the gap in the preserved caudals. Since various other Triassic ichthyosaurs have since been found to have tail bends, one was illustrated here. A modest downturn of roughly 15° was illustrated, comparable to that in Guanlingsaurus, and the location of the bend within the gap in the preserved vertebrae matches well with the location of the bend in Guizhouichthyosaurus. References McGowan, C. (1994). "A new species of Shastasaurus (Reptilia: Ichthyosauria) from the Triassic of British Columbia: The most complete exemplar of the genus". Journal of Vertebrate Paleontology 14 (2): 168–179. DOI:10.1080/02724634.1994.10011550. Nicholls, E. L.; Manabe, M. (2001). "A new genus of ichthyosaur from the Late Triassic Pardonet Formation of British Columbia: Bridging the Triassic-Jurassic gap". Canadian Journal of Earth Sciences 38 (6): 983–1002. Ji, C.; Jiang, D.Y.; Hao, W.; Sun, Y. (2011). "True tailbend occurred in the Late Triassic: Evidence from ichthyosaur skeletons of South China". Acta Scientiarum Naturalium Universitatis Pekinensis 47 (2): 309–314. Shang, Q. H.; Li, C. (2009). "On the occurrence of the ichthyosaur Shastasaurus in the Guanling biota (Late Triassic), Guizhou, China". Vertebrata PalAsiatica 47 (3): 178–193.

Reconstructed skull of Jaxartosaurus aralensis Riabinin, 1937. Only a posterior portion of the skull, as well as a surangular is known, with the rest of the skull being based mostly upon File:Aralosaurus skull.png. Jaxartosaurus is currently classified as a basal lambeosaurine, more derived than Aralosaurini, but more primitive than Parasaurolophini and Lambeosaurini. It might be more derived than Tsintaosaurini (Godefroit et al., 2004). References: Riabinin, A.M. (1937). "A New Finding of Dinosaurs in the Trans-Baikal Region". Ezhegodn. Vserossijskogo Palaeont. Obstcg. 11: 142–144 Godefroit, P.; Bolotsky, Y.L.; Van Itterbeeck, J. (2004). "The lambeosaurine dinosaur Amurosaurus riabinini, from the Maastrichtian of Far Eastern Russia". Acta Palaeontologica Polonica 49(4): 585–618

Megacephalosaurus eulerti reconstructed skull in the Rocky Mountain Dinosaur Resource Center, Woodland Park, Colorado.

Skeletal elements of Lophorhothon atopus. (A, B and C) Partial skull roof and braincase (holotype FMNH 27383) in dorsal, ventral, and left lateral views. (D) Partial left nasal of FMNH 27383 in lateral view. (E) Left prefrontal of FMNH 27383 in lateral view. (F) Partial left jugal of FMNH 27383 in medial view. (G) Detail of marginal denticles of the dentary tooth in (H). (H) Apical half of a dentary tooth crown AUMP 2295 in lingual view. (I) Maxillary tooth crown of FMNH 27383 in labial view. (J) Left pubis of AUMP 2295 in lateral view. (K) Iliac process of the left ilium of FMNH 27383 in lateral view.

The skull of the holotype of Acristavus, MOR 1155

Holotype skull of Augustynolophus morrisi (LACM 2852) on display at the Natural History Museum of Los Angeles County.

Albertosaurus skull cast (specimen TMP 1981.010.0001) at the Geological Museum in Copenhagen.

Skull of Globidens dakotensis in the Field Museum of Natural History.