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The armor-plated dinosaur Ankylosaurus magniventris is redescribed based on specimens from the Hell Creek Formation of northeastern Montana, USA., Lance Formation of Wyoming, USA., and from the Scollard Formation of south-central Alberta, Canada. Except for brief descriptions, most of these specimens have not been described in detail. Ankylosaurus is one of the largest known ankylosaurids, having an estimated length of up to 6.25 m (20.5 ft). It is characterized by a long, low skull having very prominent cranial “horns” that project laterally or dorsolaterally. The body armor includes a large half-ring that sat across the base of the neck and shoulders and a large, low tail club.

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A partial rostrum of a new species of scaphognathine pterosaur, distinguished by a thin median crest along its dorsal margin and a deep embayment of the dental margin, is the first identifiable cranial fragment of a pterosaur from the Upper Jurassic Morrison Formation of western North America. By contrast with pterodactyloids, cranial crests are rare in “rhamphorhynchoids” and this is the first record of such a structure. The new material provides fresh insights into the taxonomic diversity of Late Jurassic North American pterosaurs. Based on the ratio of the skull and skeleton of Scpahognathus, the fragment represents an individual with an estimated wing span of 2.5 m. Consequently, this is one of the largest “rhamphorhynchoids” found so far. A mandible fragment from the same quarry has closely spaced alveoli, therefore cannot be referred to the rostrum. Its large size indicates another large “rhamphorhynchoid” in the Morrison Formation.

Theoretical models of theropod forelimb biomechanics are often tainted with preconceived ideas. Actualistic modeling using specimens and casts, coupled with CAT-scans and dissections of extant vertebrate forelimbs, demonstrates that forelimb motion in theropods is considerably less than hypothetical models indicate. The forelimbs of Coelophysis, cf. Coelurus, Allosaurus, Deinonychus, and Tyrannosaurus were investigated. Motion at the shoulder, elbow, wrist, and digits were analyzed and compared with those of birds and crocodiles, then motion of the entire forelimb was examine& The results have considerable implications for forelimb use in predation. Three models of predation are recognized: 1) long armed grasper Deinonychus, cf. Coelurus; 2) clutcher -Tyrannosaurus; 3) combination grasper-clutcher -Allosaurus. Analysis of the joints of Deinonychus show that the forelimb could not fold avian fashion. The scapula of the theropod Unenlagia was oriented incorrectly and differs little from the standard theropod scapula.