In looking through the original work of Mr. Parkinson, the instructed observer will not fail to perceive the immense progress which the study of fossil animals and plants has made since the period of its first appearance in 1811. At that time, the terms Geology and Palæontology were unknown; all the sedimentary strata have since been accurately defined and arranged, and names assigned to the respective systems or formations; while the so-called _Diluvial Epoch_, which Mr. Parkinson, and even Baron Cuvier, considered as established by incontrovertible physical evidence, has been expunged from the chronology of geology. In Mr. Parkinson's volumes, no allusion will be found to that most remarkable era in the earth's history which modern researches have brought to light--_the Age of Reptiles_; the terms Ichthyosauri, Plesiosauri, Iguanodon, Megalosaurus--now familiar as household words--are not inscribed on their pages; all those marvellous beings of past ages have been discovered during the last forty years; in short, the remark of an eminent critic is as true as it is beautiful:--"Geology is a philosophy which never rests; its law is progress; a point which yesterday was invisible is its goal to-day, and will be its starting-post to-morrow." I gladly avail myself of this opportunity to make a passing allusion to the excellent and accomplished author, Mr. Parkinson. I had the pleasure and privilege of his acquaintance in my youth, immediately after the publication of the third volume of his valuable work. Mr. Parkinson was rather below the middle stature, with an energetic, intelligent, and pleasing expression of countenance, and of mild and courteous manners; readily imparting information, either on his favourite science, or on professional subjects; for he was at that time actively engaged in medical practice in Hoxton Square, and was the author of several valuable medical treatises. He kindly showed and explained to me the principal objects in his cabinets, and pointed out every source of information on fossil remains; a department of natural knowledge at that time but little cultivated in England, but which peculiar circumstances had contributed to render the engrossing object of my young and ardent mind. In after years Mr. Parkinson warmly encouraged my attempts to elucidate the nature of the strata and organic remains of my native county, Sussex, a district which was then supposed to be destitute of geological interest; and he revised my drawings, and favoured me with his remarks on many subjects treated of in my first work--"_The Fossils of the South Downs_."[5] [Footnote 5: Published in 1822.]