In the description of the skeleton of Metriorhynchus given in vol. ii of the Catalogue of the Marine Reptiles of the Oxford Clay, very little could be said about the fore-limb. The only partsthen known were a number of humeri and, in one or two cases, somesmall disc-like bones which were regarded as the radius and ulna:the most complete fore-limb was figured on p. 172 of the volumequoted. In order in some degree to fill this gap a short account wasgiven (torn, cit., Introduction, p. xiii) of an imperfect fore-paddle ofa specimen of the closely related Geosaurus graeilis from the Solenhofenlimestone. This beautiful skeleton, originally described by V. Ammon(Geognostische Jahreshefte, vol. xviii, p. 12), has recently beenacquired by the British Museum, and a photograph of it is given asa frontispiece to vol. ii of the Catalogue of Oxford Clay Reptiles. The specimen is beautifully preserved, and is remarkable for showingthe outline of the tail-fin and other traces of the soft parts.