[Illustration: FIG. 20.—The heraldic basilisk, also called the Amphysian Cockatrice. Observe the second head at the end of its tail—a feature due to perversion of the observation that there are some snake-like creatures (Amphisbena) with so simple a head that it is at first sight difficult to say which end of the creature is the head and which is the tail.] Without looking further into the strange and fantastic catalogue of imaginary monsters, one must recognise that it is a matter of great interest to trace the origin of these marvellous creations of human fancy, and the way in which they have first of all been brought into pictorial existence, and then variously modified and finally stereotyped and maintained by tradition and art. It has not infrequently been suggested, since geologists made us acquainted with the bones of huge and strange-looking fossil reptiles dug from ancient rocks, that the tradition of “the dragon” is really a survival of the actual knowledge and experience of these extinct monsters on the part of “long-ago races of men.” It is a curious fact, mentioned by a well-known writer, Mrs. Jameson, that the bones of a great fossil reptile were preserved and exhibited at Aix in France as the bones of the dragon slain by St. Michael, just as the bones of a whale are shown as those of the mythical Dun-cow of Warwick in that city. There are three very good reasons for not entertaining the suggestion that the tradition of the dragon and similar beasts is due to human co-existence with the great reptiles of the past. The first is that the age of the rocks known as cretaceous and jurassic (or oölitic), in which are found the more or less complete skeletons of the great saurians—many bigger in the body than elephants, and with huge tails in addition, iguanodon, megalosaurus, diplodocus, as well as the winged pterodactyles (see Plate II., where a representation is given of what we know as to the form and bearing of two species of pterodactyle) and a vast series of such creatures—is so enormously remote that not only man but all the hairy warm-blooded animals like him, did not come into existence until many millions of years after these rocks had been deposited by water and the great reptiles buried in them had become extinct. The cave-men of the Pleistocene period are modern, even close to us, as compared with the age when the great saurians flourished. That was just before the time when our chalk-cliffs were being formed as a slowly growing sediment on the floor of a deep sea. No accurate measure of the time which has elapsed since then is possible, but we find that about 200 ft. thickness of deposit has been accumulated since the date of the earliest human remains known to us—whilst over 5000 ft. have accumulated since the chalk began to be deposited, and the great saurians ceased to exist. If we reckon, in accordance with the most moderate estimate, a quarter of a million years for the upper 200 ft. of