Here we report on a newly collected, well-preserved vertebral centrum of a plesiosaur from the type area of the Maastrichtian Stage in southern Limburg. The specimen is interpreted as a caudal vertebra that originated from an osteologically immature or juvenile individual, as evidenced by the position of the pedicular facets, the presence of a notochord pit and the absence of fused neural arches. It adds to the meagre record of sauropterygians in the area.

An isolated, completely ossified vertebra tentatively ascribed to the non-cyamodontid placodont Pararcus diepenbroeki is described from the Anisian Vossenveld Formation in Winterswijk, the Netherlands, and compared to other material from the same locality. This fossil is the first completely ossified vertebra of the taxon and most likely originates from an adult specimen. It was recovered c. 16 m deeper in the stratigraphy than previously described material of the species, which is thus far known only from Winterswijk. Based on the slanting angle of the transverse process, the vertebra is interpreted to originate from the dorsal region. Besides the overall agreements in morphology that warrant a tentative identification as Pararcus diepenbroeki, the newly described vertebra deviates from other known Pararcus vertebrae in the presence of a longer, well-ossified neural spine and a strongly constricted, less pachyostotic and ovaloid vertebral centrum. General agreement in morphology with previously described vertebrae suggests this novel condition indicates a different anatomical position and perhaps a varied ossification pattern.

A large heterocoelous cervical vertebra from the Late Cretaceous of Cruzy (Hérault, southern France) is described and referred to the giant bird Gargantuavis philoinos Buffetaut & Le Loeuff, 1998, confirming its avian nature. Gargantuavis appears to have been a long-necked bird with possibly a relatively small skull. Derived features such as heterocoely suggest that Gargantuavis was an advanced ornithuromorph, close to ornithurines.

This article reviews the main trends in the evolution of the vertebrate axial skeleton, with special focus on mammals. The structure of vertebrae is exposed according to traditional and current conceptions and several examples of species-specific and topography-specific adapta tions are given. The relationships between stature and the anatomy of the bony girdles surrounding the spine are discussed. Hypotheses on the influence of gravity on axial morphogenesis are formulated.