modified reptiles. The first bird had a long jointed tail, and a bill well supplied with formidable teeth. It was during this period that the first representative of the class Mammalia, to which man belongs, appears. It is in the rocks of this era that we meet with remains of marsupials, the order to which opossums belong. This is the lowest of the Mammalian class. To the class Mammalia belong the most highly organized animals. They have been the ruling animals since the close of Mesozoic time. We must now watch their development with especial care. For this brief review, as far as it has gone, has shown a steady and gradual progress in life forms, the lower invariably preceding the higher. We therefore feel that it will be vain to seek for any trace of man until we find undoubted proofs of the existence of all the forms of animals below him. The last great division of time is called Cenozoic. This means new life forms. In this age, the forms of life are much nearer our own. As it was some time during this epoch when man makes his appearance, we deem it best to go into more detail, and give the subdivisions of this period. It has been amply sufficient to give simply the outlines of the other periods. In order to fix more clearly the sequence of life, we will give an outline showing the periods we have reviewed, and also the subdivisions of the Cenozoic 45 time, which we are now to examine with more care. OUTLINE. LIFE. Archaean Time. The Beginning: Includes the long lapse of time when the globe could not support life, but towards its close faint traces of life, both animal and vegetable appeared. Paleozoic Time. The Period of Old Life Forms: Forests of flowerless trees; but pines grew in the coal measures. Animal life largely invertebrate; but amphibians and reptiles among the vertebrate appear at the close. Mesozoic Time. The Period of Middle Life Forms: Flowering trees increasing in number and importance. Deciduous trees make their appearance. Animal life largely reptilian. The class Mammalia represented by marsupials. Cenozoic Time. Tertiary, or Age of Mammals: Eocene, Miocene, Pliocene. Quarternary, or Age of Man: Glacial or Pleistocene, Recent. At the close of the Mesozoic time, great elevations of land took place in both America and Europe, especially in the northern portions. This could not fail to have a great effect on life, both animal and vegetable. During the Eocene, or first division of the Tertiary Age, we have simply 46 to note the steady progress of life. There were forests of species of oaks, poplars, maples, hickories, and other common trees, and others now found only in tropical regions. Palm trees were growing in the upper Missouri region of the United States. And England was decidedly a land of Palms, as no less than thirteen species are known to have been growing there. Cypresses, yews, and pines graced the scene. Our special interest centers, however, in the mammals of this epoch. Illustration of The Paleotherium.-------- In the preceding epoch marsupials only were represented. But in beds of the middle and closing portions of the Eocene period we meet with a sudden increase of Mammalian life. Whale-like animals were especially abundant in the seas; and on our Western plains were animals like the tapirs of India, and rhinoceros-like animals as large as elephants but having no trunks, and diminutive little animals not larger than foxes, from which have come our horses. Europe also had a varied Mammalian fauna. There were numerous hog-like animals. Animals, like the tapirs of tropical Asia and America, wandered in the forests and on the banks of the rivers. Herds of horse-like animals, about the size of Shetland ponies, fed on the meadows. Animals that chew the cud were present, or at least had near representatives. Among the flesh-eating animals were creatures resembling foxes, wolverines, and hyenas. This shows what a great advance had been made. But, besides all these, we are here presented with representatives of the order of Quadrumana, or four-handed animals. Several genera of lemurs are found in both America and Europe. 47 Now the Quadrumana are the order below man. Therefore it seems that in the Eocene period, all the forms of life
below man are represented. The time seems to be at hand when we can look, with some confidence, for traces of the presence of man himself. We must therefore be more cautious in our investigations. The epoch following on after the Eocene is designated as the Miocene. We must remember that, though recent in a geological sense, yet it is immensely remote when measured by the standard of years. We must inquire into all the surroundings of this far away time. The geographical features must have been widely different from the present. In the first place, the elevation of land to the north must have been sufficient to have connected the land areas of the Northern Hemisphere--North America, with Asia and Greenland; and this latter country must have been united with Iceland, and, through the British Islands, with Europe. But, to compensate for this land mass to the north, large portions of Central and Southern Europe were beneath the waves. The proof of this extended mass of land is to be found in the wide distribution of similar animals and plants in the Miocene time. All the chief botanists are agreed that the north Polar region was the center from which plants peculiar to the Eocene and Miocene epochs spread into both Europe and America. We may mention that the famous big trees of California are simply remnants of a widespread growth of these trees in Miocene times. They can be found in a fossil state at various places in British America, in Greenland, and in Europe. They are supposed to have originated somewhere in the north, and spread by these land connections we have mentioned into both Europe and America. But 48 this is not the only tree that grew in the Miocene forests of both continents. The magnolia, tulip-tree, and swamp cypress are other instances. Eleven species, growing in the Rocky Mountain regions in Rocene times, found their way to Europe in the Miocene times, driving before them the plants of a tropical growth that had hitherto flourished in England. Now this implies land connection between the two continents. Furthermore, animals both large and small are found common to the two countries. The climate over what is now the North Temperate Zone, and even further. north, must have been delightful. There is ample testimony to this effect in the rich vegetative remains over wide areas. In Spitzbergen, within twelve degrees of the pole, where now a dwarf willow and a few herbaceous plants form the only vegetation, and the ground is most of the time covered with snow and ice, there were growing, in Miocene times, no less than ninety-five species of trees, including yews, hazels, elders, beech, elms, and others. But it is in the Miocene forests of the continent of Europe where we meet with evidence of a singularly mild climate. There were at least eleven species of palms growing in Switzerland; and one variety of them grew as far north as Northern Germany. We can not give a list of all the species. On the one hand, there were elms, willows, poplars, oaks, and beeches, thus far similar to the forest growth of temperate regions. Mingled with these were forests of trees like the tulip-tree, swamp cypress, and liquid amber or sweet gum of the southern part of the United States--plants whose home is in the warm and moist regions of the earth. But there were also representatives 49 of the tropical regions--such as fig-trees, cinnamon-trees, and camphor-trees: these are found growing now in tropical countries. Fruit-trees of the cherry, plum, and almond species were also to be seen. Prof. Heer points out how all this should convince us that a large part of Europe, in the Miocene Age, possessed a climate not unlike that of the Madeira or Canary Islands to-day. He calls especial attention to the fact that these trees were nearly all of evergreen species, and that a severe winter would destroy them. He finds one hundred and thirty-one species of the Temperate Zone--species that can stand a moderate amount of cold, but not very hot and dry climates. He finds eighty-five species of tropical plants that could not possibly live where the Winters are severe. Mingled with these were nearly three hundred species whose natural home is in the warm, temperate portions of the earth. The only way you can explain this motley assemblage of trees is, to suppose that in what is now Europe was a climate free from extremes, allowing the trees to put forth flowers and fruits all the year round. "Reminding us," says Prof. Heer, "of those fortunate zones where Nature never goes to rest." Illustration of Miocene Mammals.----------- Let us now inquire as to the animals that roamed through these great forests we have been describing. The Miocene period extended over a long lapse of time, and considerable change took place among the animals belonging to the different parts of this age. We will only give a general outline for the whole period. The marsupials lingered along into the early stages of this period, and then disappeared from Europe. The rhinoceros were present in the early stages, and continued through the 50 entire age. We meet in this period animals of the elephant kind, two species, the mastodon and deinotherium. Antelopes and gazelles wandered in vast troops over the plains of Hungary, Spain, and Southern France. Carnivorous animals resembling tigers and hyenas found abundance of animal food. Herds of horse-like animals fed on the rich herbage of the meadows. The birds were largely represented. In the woods were to be seen flocks of gayly feathered paroquets and trogons. On the plains secretary-birds hunted the serpents and reptiles, which furnished them food--and eagles were on the watch for their
