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PALAEONTOLOGY species now known as Morosaurus brevis. Still smaller vertebra of the same, together with teeth erroneously assigned by Mantell to the under- mentioned Hylceosaurus, from Cuckfield and Tilgate Forest, have been made the types of another species of dinosaur by the present writer under the name of Pleuroccelus valdensis, the generic name being first given to a North American dinosaur. Quite another type of dinosaur is indicated by Hylceosaurus armatus, a genus and species known only from the Wealden of Battle, Bolney and Tilgate. It was armed with a number of large bony spines, probably carried in one or more rows along the back. A lower jaw from the Wealden of Cuckfield described by Mantell under the name of Regnosaurus northamptoni probably indicates a reptile nearly allied to, if not identical with, the last ; the specific name was applied in honour of a former Marquis of Northampton, and does not refer to the locality of the specimen. The carnivorous dinosaurs are represented by a species of the Jurassic genus Megalosaurus, which has been named by the present writer M. oweni ; its remains have been recorded from Battle, Cuckfield and Hastings. Some remains of the same genus from the Wealden of the county have been assigned to a continental species, M. dunkeri. Of the crocodiles of the Wealden of the county, one of the most abundant is Goniopholis crassidens, a genus and species first described by Mantell from the Purbeck of Swanage ; its remains occur at Cuckfield and Horsham, and a nearly perfect skull is preserved in the Brighton Museum. The bony plates protecting the body of this crocodile are articulated together by means of a peg-and-socket arrange- ment. Vertebra from Cuckfield have been regarded as indicating a second species of the genus, named G. carinata. Crocodilian teeth from Cuckfield and Tilgate Forest of a different shape to those of Goniopholis — having a pair of sharp vertical ridges on opposite sides of the crown — have been made the type of a distinct genus under the name of Sucho- saurus cultridens. Finally, a more modern type of crocodile from the Wealden of Cuckfield and Hastings has been described as Heterosuchus valdensis ; but it does not seem certain that it is really distinct from a crocodile from the Belgian Wealden named Hylaochampsa. Several kinds of freshwater tortoises are known from the Wealden strata of the county, most of these belonging to a group now restricted to the southern hemisphere. An exception in this respect is however a very remarkable Chelonian from Cuckfield and Tilgate Forest described by Mantell as Trionyx bakewelli, but now known as 'Tretosternum bakewelU. Although the shell is sculptured, the nearest living ally of the genus (unfortunately very imperfectly known) is the American snapper {Chelhydrd). A second, unnamed, species of the genus occurs in the Wadhurst Clay of Hastings. The Chelone belli of Mantell, from Tilgate Forest, is now referred to the genus Hylceochelys, typically from the Purbeck of Swanage, where it is represented by H. latiscutata. To the latter species is assigned an imperfect shell in the British Museum from the Wealden of Burwash in the county under consideration. The 37