Skeleton of a Radiolarian Very Greatly Enlarged
The very rocks themselves may consist largely of fossils; chalk, for example, is mainly made up of the disintegrated shells of simple marine animals called foraminifers, and the beautiful flint-like "skeletons" of other small creatures termed radiolarians, minute as they are, have contributed extensively to the formation of some strata.
Where a Dinosaur Sat Down
In the light of our present knowledge we are able to read many things in these tracks that were formerly more or less obscure, and to see in them a complete verification of Dr. Deane's suspicion that they were not made by birds. We see clearly that the long tracks called Anomœpus, with their accompanying short fore feet, mark where some Dinosaur squatted down to rest or progressed slowly on all-fours, as does the kangaroo when feeding quietly;[3] and we interpret the curious heart-shaped depression sometimes seen back of the feet, not as the mark of a stubby tail, but as made by the ends of the slender pubes, bones that help form the hip-joints. Then, too, the mark of the inner, or short first, toe, is often very evident, although it was a long time before the bones of this toe were actually found, and many of the Dinosaurs now known to have four toes were supposed to have but three.
The Track of a Three-toed Dinosaur
The Track of a Three-toed Dinosaur
A Great Sea Lizard Tylosaurus Dyspelo
The finest Mosasaur skeleton ever discovered, an almost complete skeleton of Tylosaurus dyspelor, 29 feet in length, may be seen at the head of the staircase leading to the Hall of Paleontology, in the American Museum of Natural History, New York. Another good specimen may be seen in the Yale University Museum, which probably has the largest collection of Mosasaurs in existence.
Koch's Hydrarchus. Composed of Portions of the Skeletons of Several Zeuglodons
One might think that a creature sixty or seventy feet long was amply long enough, but Dr. Albert Koch thought otherwise, and did with Zeuglodon as, later on, he did with the Mastodon, combining the vertebræ of several individuals until he had a monster 114 feet long! This he exhibited in Europe under the name of Hydrarchus, or water king, finally disposing of the composite creature to the Museum of Dresden, where it was promptly reduced to its proper dimensions. The natural make-up of Zeuglodon is sufficiently composite without any aid from man, for the head and paddles are not unlike those of a seal, the ribs are like those of a manatee, and the shoulder blades are precisely like those of a whale, while the vertebræ are different from those of any other animal, even its own cousin and lesser contemporary Dorudon
A Tooth of Zeuglodon, One of the 'Yoke Teeth,' from which it derives the name
The best Zeuglodon, the first to show the vestigial hind legs and to make clear other portions of the structure, is in the United States National Museum
Nature's Four Methods of Making a Wing - Bat, Pteryodactyl, Archæopteryx, and Modern Bird
Nature's Four Methods of Making a Wing - Bat, Pteryodactyl, Archæopteryx, and Modern Bird
Hesperornis, the Great Toothed Diver
Young Hoactzins
Archæopteryx
Thespesius, a Common Herbivorous Dinosaur of the Cretaceous
A Hind Leg of the Great Brontosaurus, the Largest of the Dinosaurs
A Single Vertebra of Brontosaurus
Skeleton of Triceratops
The Horned Ceratosaurus, a Carnivorous Dinosaur
Skull of Ceratosaurus
Skull of Phororhacos Compared with that of the Race-horse Lexington
Leg of a Horse Compared with that of the Giant Moa
The Three Giants, Phororhacos, Moa, Ostrich
Skeleton of the Modern Horse and of His Eocene Ancestor
The Development of the Horse
Skeleton of the Mammoth in the Royal Museum of St. Petersburg
The Mammoth as Engraved by a Primitive Artist on a Piece of Mammoth Tusk
Tooth of Mastodon and of Mammoth
The Missourium of Koch, from a Tracing of the Figure Illustrating Koch's Description
The Mastodon
Phororhacos, a Patagonian Giant of the Miocene
Phororhacos, a Patagonian Giant of the Miocene From a Drawing by Charles R. Knight Most recent in point of discovery, but oldest in point of time, are the giant birds from Patagonia, which are burdened with the name of Phororhacidæ, a name that originated in an error, although the error may well be excused. The first fragment of one of these great birds to come to light was a portion of the lower jaw, and this was so massive, so un-bird-like, [149]that the finder dubbed it Phororhacos, and so it must remain.
Cephalaspis and Loricaria, an Ancient and a Modern Armored Fish
Still higher up we come upon the abundant remains of numerous small fish-like animals, more or less completely clad in bony armor, indicating that they lived in troublous times when there was literally a fight for existence and only such as were well armed or well protected could hope to survive. A parallel case exists to-day in some of the rivers of South America, where the little cat-fishes would possibly be eaten out of existence but for the fact that they are covered—some of them very completely—with plate-armor that enables them to defy their enemies, or renders them such poor eating as not to be worth the taking. The arrangement of the plates or scales in the living Loricaria is very suggestive of the series of bony rings covering the body of the ancient Cephalaspis, only the latter, so far as we know, had no side-fins; but the creatures are in no wise related, and the similarity is in appearance only.
Pterichthys, the Wing Fish
erichthys, the wing fish, was another small, quaint, armor-clad creature, whose fossilized remains were taken for those of a crab, and once described as belonging to a beetle. Certainly the buckler of this fish, which is the part most often preserved, with its jointed, bony arms, looks to the untrained eye far more like some strange crustacean than a fish, and even naturalists have pictured the animal as crawling over the bare sands by means of those same arms. These fishes and their allies were once the dominant type of life, and must have abounded in favored localities, for in places are great deposits of their protective shields jumbled together in a confused mass, and, save that they have hardened into stone, lying just as they were washed up on the ancient beach ages ago. How abundant they were may be gathered from the fact that it is believed their bodies helped consolidate portions of the strata of the English Old Red Sandstone.