[66] _The Natural History of Pliny._ Translated by J. Bostock and H. T. Biley, 6 vols. Bohn, London, 1857. [67] _Æliani de Natura Animalium_, F. Jacobs. Jenæ, 1832. [68] _Géographie d'Edrisi, traduite de l'Arabe en Français_, P. Amédée Jaubert, 2 vols. Paris, 1836. [69] _Phil. Trans._, vol. cxlix. p. 43, 1859; vol. clxxi. p. 1,037, 1880; vol. clxxii. p. 547, 1881. [70] Description of some New Species and Genera of Reptiles from Western Australia, discovered by John Gould, Esq., _Annals and Magazine of Natural History_, vol. vii. p. 88, 1841. [71] "We shall, I think, eventually more fully recognise that, as is the case with the periods of the day, each of the larger geological divisions follows the other, without any actual break or boundary; and that the minor subdivisions are like the hours on the clock, useful and conventional rather than absolutely fixed by any general cause in Nature."--Annual Address, President of Geological Society, 1875. "With regard to stratigraphical geology, the main foundations are already laid, and a great part of the details filled in. The tendency of modern discoveries has already been, and will probably still be, to fill up those breaks, which, according to the view of many, though by no means all geologists, are so frequently assumed to exist between different geological periods and to bring about a more full recognition of the continuity of geological time. As knowledge increases, it will, I think, become more and more apparent that all existing divisions of time are to a considerable extent local and arbitrary. But, even when this is fully recognised, it will still be found desirable to retain them, if only for the sake of convenience and approximate precision."--Annual Address, President of Geological Society, 1876.