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New specimens of caenagnathid theropods are described from the Judith River Formation (Campanian) of southern Alberta, the Hell Creek Formation (Maastrichtian) of South Dakota, and the Bissekty Formation (Turonian) of Uzbekistan. With the exception of the Hell Creek specimen, and a vertebra from Alberta, all are from the symphysial regions of the lower jaws. Caenagnathids are rare and poorly known animals, and the described fossils preserve heretofore unknown features, including vascular grooves and foramina in the symphysial region, and the pattern of overlapping sutures between jaw elements. Most of the new specimens are different from the holotype of Caenagnathus collinsi Sternberg and may represent the second described species, Caenagnathus sternbergi. The two jaws from the Bissekty Formation are the first oviraptorosaurian jaws described from Uzbekistan and represent a new genus and species anatomically closer to Caenagnathus than to central Asian forms like Oviraptor, Conchoraptor and Ingenia. There are at least five characters that distinguish caenagnathid and oviraptorid jaws, but it is concluded that the length of the symphysial region must be used with caution. Jaw anatomy supports the idea that oviraptorids were well adapted for eating eggs, although their diet was probably not restricted to one food type.

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The structure of the olfactory apparatus is not well known in both archaic and extant whales; the result of poor preservation in most fossils and locational isolation deep within the skulls in both fossil and Recent taxa. Several specimens now shed additional light on the subject. A partial skull of an archaic cetacean is reported from the Pamunkey River, Virginia, USA. The specimen probably derives from the upper middle Eocene (Piney Point Formation) and is tentatively assigned to the Protocetidae. Uncrushed cranial cavities associated with the olfactory apparatus were devoid of sediment. CT scans clearly reveal the dorsal nasal meatus, ethmoturbinates within the olfactory recess, the cribriform plate, the area occupied by the olfactory bulbs, and the olfactory nerve tract. Several sectioned skulls of the minke whale (Balaenoptera acutorostrata) were also examined, and olfactory structures are remarkably similar to those observed in the fossil skull from the Pamunkey River. One important difference between the two is that the fossil specimen has an elongate olfactory nerve tract. The more forward position of the external nares in extant balaenopterids when compared with those of extant odontocetes is interpreted to be the result of the need to retain a functional olfactory apparatus and the forward position of the supraoccipital/ cranial vertex. An increase in the distance between the occipital condyles and the vertex in balaenopterids enhances the mechanical advantage of the epaxial musculature that inserts on the occiput, a specialization that likely stabilizes the head of these enormous mammals during lunge feeding. Anat Rec, 296:257-272,