Among these we find for the first time in our upward progress in the history of the earth, species of our familiar oaks, figs, and walnut, along with some trees now confined to Australia and the Cape of Good Hope, as the banksias and "silver-trees," and their allies. In America a large number of the genera of the modern trees are present, and even some of those now peculiar to America, as the tulip-trees and sweet-gums. These forests of the later Mesozoic must therefore have been as gay with flowers and as beautiful in foliage as those of the modern world, and there is evidence that they swarmed with insect life. Further, the Mesozoic plants produced in some places beds of coal comparable in value and thickness to those of the old coal formation. Of this kind are the coal beds of Brora in Sutherlandshire, those of Richmond in Virginia, and Deep River in N. Carolina, those of Vancouver's Island, and a large part of those of China. To the same age have been referred some at least of the coal beds of Australia and India. So important are these beds in China, that had geology originated in that country, the Mesozoic might have been our age of coal. If the forests of the Mesozoic present a great advance over those of the Palæozoic, so do the animals of the land, which now embrace all the great types of vertebrate life. Some of these creatures have left strange evidence of their existence in their footprints on the sand and clay, now cemented into beds of hard rock excavated by the quarryman. If we had landed on some wide muddy Mesozoic shore, we might have found it marked in all directions with animal footprints. Some of these are shaped much like a human hand. The creature that made this mark was a gigantic successor of the crocodilian newts or labyrinthodonts of the Carboniferous, and this type seems to have attained its maximum in this period, where one species, _Labyrinthodon giganteus_, had great teeth three or four inches in length, and presenting in their cross section the most complicated foldings of enamel imaginable. But we may see on the shores still more remarkable footprints. They indicate biped and three-toed animals of gigantic size, with a stride perhaps six feet in length. Were they enormous birds? If so, the birds of this age must have been giants which would dwarf even our ostriches. But as we walk along the shore we see many other impressions, some of them much smaller and different in form. Some, again, very similar in other respects, have four toes; and, more wonderful still, in tracing up some of the tracks, we find that here and there the creature has put down on the ground a sort of four-fingered hand, while some of these animals seem to have trailed long tails behind them. What were these portentous creatures--bird, beast, or reptile? The answer has been given to us by their bones, as studied by Yon Meyer and Owen, and more recently by Huxley and Cope. We thus have brought before us the _Dinosaurs_--the terrible