In 1856 the first Batrachian bones were described from the United States. These were discovered by Dr. Newberry and C. M. Wheatley, at Linton, Jefferson County, Ohio. There were three different types of beings. The first had the head and ribless trunk of a frog, combined with the limbs and tail of a salamander. The second and third had the vertebræ of a salamander, with the ribs of a serpent. The first of these animals has been named Raniceps Lyelli by Dr. Wyman, of Boston.

In 1863, Professor O. C. Marsh described, from the coalmeasures of South Joggins, Nova Scotia, the remains of a reptile somewhat higher in rank than any other previously known in rocks of so high antiquity-a true reptile belonging to the Enaliosaurs, or marine saurians, and related to the huge reptiles which sported in the waters of the Mesozoic time, some of which have been so genially described by Dr. Mantell. This animal, which is believed to have been from twelve to fifteen feet in length, was probably one of the most fish-like of Enaliosaurs. It has been named Eösaurus Acadianus.

How scattered must have been the air-breathing population of the globe when, after thirty years of careful observations, geologists have brought to light only the foregoing brief list from the carboniferous rocks of the country. I make no note of two or three species of air-breathing snails, a myriapod, and two or three orthopterous insects. Seven species only of vertebrate air-breathers-intrepid forerunners of the numerous populations of the succeeding periods-scouts, sent forward upon the earth to spy out the land, and test its fitness for the occupancy of the hordes which were to follow!

The coal had been deposited; cubic miles of fuel for the consumption of future generations had been taken from the atmosphere, and packed in beds of clay and sand, to await

the arrival of a far-off race. The air was fit for the respiration of a low order of terrestrial animals, and, in obedience to the mandates of creative energy, they began to come forth. There was an interval of time in the history of the world when the scales of empire hung balanced between the fishes and the reptiles. The first were on the wane; the latter were gathering strength from age to age. Nature favored the latter. Omnipotence bade them march on, and vanquish and sweep from the earth those lower forms which had been permitted to hold the mastery in creation only because the world was, as yet, unfit for beings more exalted and worthy. These middle ages are styled the Permian period. Vegetation was still abundant. Though the acme of vegetable luxuriance had passed, and no more vast deposits of coal were to be treasured up―at least in those portions of the world preparing for the occupancy of the Caucasian race-the trunks and leaves of the flora of that period, preserved in beds of sandstone and shale, attest the productiveness of the Permian soil. In these ages of the world the first emphatically lizard-like reptiles came upon the stage-a family belonging to the Saurians-though many of the Permian reptiles present a divergence from true lizards in having their numerous teeth implanted in sockets instead of soldered to the margins of the jaws. Occasionally, also, was to be seen the frog-like form of a Labyrinthodont sunning himself upon the marshy border of a Permian estuary (Fig. 69).

Until within a few years geologists were unacquainted with any Permian rocks upon the American continent. Dr. Emmons, however, in 1856, established the existence of Permian reptiles in a brown sandstone in North Carolina, deposited in some of the furrows between the folds of the Appalachian upheaval. A little later, Permian rocks were announced from Kansas almost simultaneously by

Swallow, Meek, and Hall. The Permian rocks west of the Mississippi have more recently been subjected to thorough investigations by Swallow, Meek, Hayden, and Shumard; and though much of what was first regarded as Permian is now proven to belong to the period of the coal-measures, we know that this group of sediments is developed in America on a scale little less magnificent than in the ancient Russian kingdom of Perm, which gave its name to the group.

WE

CHAPTER XVI.

THE REIGN OF REPTILES.

E now enter upon a new Age in the history of the world. The reptilian army has arrived and taken absolute possession of the land and the sea. The highest of these monarch reptiles, in respect to organization, are some lizard-like creatures as much at home in the sea as upon the land. But especially does the great deep swarm with huge beings having the body of a lizard, the immense jaws and sharp, conical teeth of a crocodile, the bi-concave vertebræ of a fish, and the short, flat paddles of a whale. What a synthesis of characters is here! The type of the age is expressed in the lacertiform trunk and tail. Crocodiles had not yet existed; but the jaws of these monsters seem like an experiment preparatory to the supply of quantities of those savage brutes. Mammals were yet in the distant future; but here, in the paddles of these Enaliosaurs is a prophecy of coming cetacea-the form which the mammalian type assumes at the point where it comes in contact with the type of fishes. The reign of fishes is past; but here, in the bi-concave vertebræ of these sea-monsters is preserved a reminiscence of the last sovereigns.

This, the Triassic Age, was peculiarly the reign of Labyrinthodont saurians. Thirty-five years ago the tracks of these anomalous creatures were first noticed upon some red sandstone in Saxony, and they have since been discovered in other parts of the world. The peculiarity of these footprints consists in their hand-like form, and in the occurrence of a series of larger and smaller in connection with

each other. The latter circumstance led to the opinion that the posterior limbs of the reptile were much stouter than the anterior, as in the kangaroo and frog. When the bones of these animals were brought to light, geologists had the opportunity to certify themselves that these problematical hand-prints were impressed by reptilian instead of mammalian quadrupeds; and that while the weight of characters allied them to true reptiles, they nevertheless possessed strong analogies with Batrachians, and probably simulated the form and habits of the frog-though in truth we should say that the frog was subsequently fashioned in the similitude of a Labyrinthodont. The head was helmeted by a pair of broad, bony plates, through which were openings for the eyes; and some parts of the body were covered, especially in the later ages, by a similar armor. The striking characteristic of these ancient reptiles, from which they receive their name, is seen when a very thin transverse section or slice of one of the teeth is viewed under the microscope. The external coating of the tooth, called cement, is folded inward in folds which reach to the central cavity, and in their course are inflected into a labyrinth of subordinate lateral folds. Some of these frog-like quadrupeds seem to have attained the size of an ox. It is likely that they were the representatives of the class of Batrachians in those early periods, as no other Batrachia are known in the Trias; and those before alluded to from the coal-measures are known likewise to have possessed the peculiar cephalic plates of the Labyrinthodonts.

The Triassic Age witnessed also the advent of multitudes of marine saurians of the family of Ichthyosaurs, having enormous cavities in their craniums for the lodgment of the eyes. This type of reptiles is restricted to this single age of the world. Here also crawled reptiles resembling gigantic lizards, semi-aquatic or purely terrestrial in