Two elongatoolithid dinosaur eggs from the Upper Cretaceous of Ganzhou, Jiangxi Province and the embryonic skeletons they bear are described. They represent the first oviraptorosaurian eggs with embryonic skeletons in China and provide the first example that an oospecies can be correlated to certain dinosaur taxon/taxa. The two eggs are the same as the pair of the eggs inside a female oviraptorosaurian pelvis from the same horizon of the same area in both macro- and micro-structures of the egg shells, and can he referred to the oospecies, Macroolithus yaotunensis Zhao, 1975. The morphology of the preserved part of the embryonic skeletons indicates that they may have been laid by an oviraptorid, Heyuannia huangi from Guangdong Province or a closely related oviraptorosaurian, which may have been lived in the Ganzhou area too in the Late Cretaceous. The embryonic skeletons of the two eggs are not in the same developing stage. In one of the eggs, the postzygapophysis of the preserved vertebrae are well ossified, indicating that it was just hatched.
The Nyctosaurus specimen K J1 was reconstructed under the hypothesis that there is a membrane attached to the crest; the so-called headsail crest. The aerodynamic forces and moment acting on the headsail crest were analyzed. It was shown that K J1 might adjust the angle of the headsail crest relative to the air current as one way to generate thrust （one of the aerodynamic forces, used to overcome body drag in forward flight） and that the magnitude of the thrust and moment could vary with the gesture angle and the relative location between the aerodynamic center of the headsail crest and body＇s center of gravity. Three scenarios were tested for comparison： the crest with membrane attachment, the crest without membrane attachment and the absence of a cranial crest. It was shown that the aerodynamic characteristics （increasing, maintaining and decreasing thrusts and moment） would have almost disappear in flight for the crest without membrane attachment and was non-existent without the cranial crest. It is suggested from aerodynamics evidence alone that Nyctosaurus specimen KJ1 had a membrane attached to the crest and used this reconstructed form for auxiliary flight control.
An incomplete specimen of Sinosauropteryx prima collected from the Early Cretaceous Yixian Formation of the Dawangzhangzi area in Lingyuan, western Liaoning is depicted. It represents the first systematically described material of this feathered compsognathid outside the Sihetun area in Beipiao. This specimen shows some diagnostic features of Sinosauropteryx prima, such as the very short forelimb in relation to hindlimb with the length ratio of humerus plus radius to femur plus tibia just around 30%, and the long and massive first manual ungual subequal in length to radius. The presence of Sinosauropteryx prima only at Sihetun and Dawangzhangzi supports the suggestion that the fossil-bearing beds in the Sihetun and Dawangzhangzi areas are equivalent to each other within the Yixian Formation.
JI Shu＇anGAO ChunlingLIU JinyuanMENG QingjinJI Qiang
A new compsognathid dinosaur, Sinocalliopteryx gigas gen. et sp. nov., is erected based on a complete skeleton from the Early Cretaceous Yixian Formation of western Liaoning, northeastern China. It shares the features with Huaxiagnathus orientalis in having a manus as long as the humerus plus radius, very large and subequally long manual claws I and H, and reduced olecranon process on the ulna. But it differs from Huaxiagnathus orientalis in having the much large size, a very long maxillary process of premaxilla not extending the vertical level of the maxillary antorbital fossa, and the proportionally longer ulna and so on. Sinocalliopteryx gigas gen. et sp. nov. represents the largest species among the known compsognathid dinosaurs, suggesting the tendency of the body enlargement in compsognathids to some extent. The long filamentous integuments are attached to the whole body of this compsognathid, confirming that such integuments evolved firstly in the basal coelurosaurs. This new giant compsognathid was a fierce carnivorous theropod, as shown further by an incomplete dromaeosaurid leg inside its abdominal cavity.
The structure and orientation of the posterior extremity （tail club） of the caudal vertebrae of Mamenchisaurus hochuanensis Young and Chao, 1972 from the Upper Jurassic Shangshaximiao Formation has been analyzed to determine the tail club function using Finite Element Analysis. Of the four caudal vertebrae composing the tail club, the second largest （C＂1＂） was probably the most proximal, and is fixed with the preceding sequence of the caudal vertebrae, whereas the smallest （C＂4＂） is free and forms the termination of the tail club. Our analysis also suggests that the tail club is more efficient in lateral swinging rather than up-and-down motion, and that the best region for the tail club to impact is at the spine of the largest of the four caudals （C＂2＂）, with a maximum load for impact at about 450 N. The tail club of Mamenchisaurus hochuanensis probably also had limitations as a defense weapon and was more possibly a sensory organ to improve nerve conduction velocity to enhance the capacity for sensory perception of its surroundings.
