ABSTRACT-The osteohistology including bone cross-sectional geometry of skeletal elements such as the limb bones, ribs, and intercentra of three Triassic temnospondyl taxa from India were examined to reveal varied bone microstructure and differing growth patterns. The Early Triassic trematosaurid examined is characterized by a change in tissue type from a wellvascularized fibrolamellar bone early in ontogeny to peripheral lamellar bone and lines of arrested growth later in ontogeny, suggesting a fast initial growth followed by a slow and intermittent growth later in life. In contrast, the Middle Triassic paracyclotosaurid and the Late Triassic chigutisaurid examined had a cyclical, overall slow growth, as evidenced from predominance of lamellar bone in the cortex. It is hypothesized that the rapid growth of the trematosaurids was an attempt to stabilize the ecosystem after the Permo-Triassic extinction event. Fibrolamellar bone tissue is described for the first time in a Triassic temnospondyl. Bone cross-sectional geometry, low-to-average cortical porosity, and other parameters imply that the members of the Early and Middle Triassic taxa recovered from India retained a high level of terrestriality. The high cortical porosity and extensive medullary spongiosa suggest that the Late Triassic chigutisaurids had a semi-aquatic or aquatic life style. The varying cortical thickness of the limb bones in paracyclotosaurids may be attributed to different biomechanical constraints.

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The sauropod dinosaur, Barapasaurus tagorei, is known from the Early Jurassic Kota Formation (Sinemurian to Pliensbachian) of India. The taxon is represented by c. 300 bones that were found associated with large fossilized tree trunks and were collected from the interface of sandstone and mudstone units covering an area of c. 276 m 2 . The collection includes one partial skeleton; most of the remainder of the bones were disarticulated, disassociated and dispersed, but taphonomic analysis permits recognition of associated elements comprising several individuals. Skeletal anatomy of Barapasaurus includes several teeth, vertebrae from the caudal cervicals rearward to the terminal caudals, and most elements of the appendicular skeleton. Barapasaurus is characterized by spoon-shaped teeth with bulbous bases and grooves on the anterolabial and posterolingual sides of the crown, coarse tubercles on the carina, acamerate cranial and dorsal vertebrae, lateral laminae of the middle and caudal dorsal neural spines composed of spinodiapophyseal and spinopostzygapophyseal laminae, neural canal of the mid-dorsal vertebrae opens dorsally through a narrow slit into a large cavity and sacrum with four co-ossified vertebrae. Phylogenetic analysis reveals that Barapasaurus is basal in comparison with Vulcanodon and is removed from Eusauropoda.

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