The New Student's Reference Work/Reptiles

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Reptiles (rĕp′tĭlz), a class of vertebrates, embracing four natural orders of living forms: I. Chelonia, the tortoises and turtles; II. Lacertilia, the lizards; III. Ophidia, the snakes and serpents; IV. Crocodilia, the crocodiles, alligators etc. The hatteria of New Zealand is related to the lizards, but stands in a group by itself. In the evolution of life the reptiles were the forms that first became independent of the water and began to live entirely on land. Reptiles and birds, although so different in form and habits, are united by many peculiarities of structure. Huxley proposed a common name (Sauropsida) uniting the two classes. In addition to the living forms there are many extinct forms which extend the classification and best show the resemblances between birds and reptiles. The plesiosaurs were enormous water-animals with extremely long necks. Fossils are found indicating their length to have been about 40 feet. The ichthyosaurs were long water-animals attaining 30 or 40 feet in length. The dinosaurs show many bird-like peculiarities. They lacked the power of flight and lived both on land and in the water. Some forms reached a length of 60 feet. The pterodactyls were flying reptiles with membranous, wings, which in some cases had an expanse of 25 feet.