. The Cambridge natural history. Zoology. ICHTHYOSAURI 483 creature was rolled about by the waves of the surf ou the Liassic muddy beach until it was wrapped in a mantle of clay and then imbedded on the shore. The distribution of Ichthyosaurs in time and space is wide. The earliest are found in the Middle Trias; in the Lias they are very conrmon, fairly frequent in the Oolites, dying out with the Cretaceous epoch. They have left no descendants, being far too specialised, and their origin is quite unknown. Mixosam-us, the oldest genus, occurred in Europe, and has also been found in the Triassic
. The Cambridge natural history. Zoology. ICHTHYOSAURI 483 creature was rolled about by the waves of the surf ou the Liassic muddy beach until it was wrapped in a mantle of clay and then imbedded on the shore. The distribution of Ichthyosaurs in time and space is wide. The earliest are found in the Middle Trias; in the Lias they are very conrmon, fairly frequent in the Oolites, dying out with the Cretaceous epoch. They have left no descendants, being far too specialised, and their origin is quite unknown. Mixosam-us, the oldest genus, occurred in Europe, and has also been found in the Triassic strata of Spitsbergen. Ichthyosaurus, the chief genus, is known from the Liassic, Oolite, and Cretaceous strata of Europe, a famous place being Lyme Eegis; and also from the Cretaceous. Fig. 115.—Restored outlines oi Ichthyosaurus quadriscissus. (After Jj'raas.) strata of Queensland and New Zealand. The Jurassic of Wyoming has yielded Baptanodon. Order ICHTHYOSAURI. The few genera are easily recognised. Mixosaurus, Triassic, with radius and ulna still elongated, a longitudinal space occurring between them. Both jaws with numerous uniform teeth. Ichthyosaurus, with much shortened radius and ulna; both jaws with uniform series of teeth. Many species are known, some with four to five, others with several additional and incom- plete rows of fingers and toes. /. trigonodon of the Lias in Wurtemberg seems to have reached the size of 30 feet, the vertebrae showing a diameter of 9 inches, while the skull is 6 feet long. I. comraunis and /. tenuirostris are common in the English Lias. The long-snouted I. campylodon, with large, spaced teeth, occurs in the Gault of Cambridge, Dover, and France ; and. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Harmer, S. F. (Sidney Frederic), Sir, 1862- ed; Shipley, A. E. (Arth
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