- 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. - The Caterpillar of the Small Elephant Hawk-moth (Chærocampa porcellus)
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). First stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Second Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Just before the second moult.
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Third Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Fourth Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Fifth Stage
- The Caterpillar of the Elephant Hawk-Moth (Chærocampa elpenor). Full grown
- The Caterpillar of the Eyed Hawk-Moth (Smerinthus ocellatus)
- The Caterpillar of the Marbled White Butterfly (Arge galathea)
- King Snake
- Rainbow Darter
- Long-eared Sunfish
- Floral Divider
Floral Divider on circular background - Bat
Bat - Sleeping Bat
- Nest of Phœbe
- Nest of Red-eyed Vireo
- Baltimore Oriole and Nest
- A Wolf
- Nest of the Chicadee
- Chipmunk
- Turtle
Turtle - A Lamprey
- Chinch Bug
- Thirteen-Spotted Lady Beetle
- Pouched Frog
- The Surinam Toad
- Chrysalis of Tomato Worm
- Centipede
- Trout
Trout - Female Stickleback Laying Eggs in Nest
Female Stickleback Laying Eggs in Nest - Male Stickleback Watching Eggs in Nest
Male Stickleback Watching Eggs in Nest - Female Stickleback about to Enter Nest
Female Stickleback about to Enter Nest - Hand of Gorilla, Orang, Gibbon, and Chimpanzee
- Head of Orang-Utan
- chimpanzee
- Gorilla