. A manual of zoology for the use of students : with a general introduction on the principles of zoology . Zoology. EXTINCT ORDERS OF REPTILES. 449 supposed Triassic age in South Africa and India, but Rhyncho- saurus occurs in the Trias of Europe. Order VIII. Pterosauria.—This order includes a group of extraordinary flying Reptiles, all belonging to the Mesozoic epoch, and exhibiting in many respects a very extraordinary combination of characters. The most famiUar members of the order are the so-called " Pterodactyles," and the following are the characters of the order :— No exoskele
. A manual of zoology for the use of students : with a general introduction on the principles of zoology . Zoology. EXTINCT ORDERS OF REPTILES. 449 supposed Triassic age in South Africa and India, but Rhyncho- saurus occurs in the Trias of Europe. Order VIII. Pterosauria.—This order includes a group of extraordinary flying Reptiles, all belonging to the Mesozoic epoch, and exhibiting in many respects a very extraordinary combination of characters. The most famiUar members of the order are the so-called " Pterodactyles," and the following are the characters of the order :— No exoskeleton is known to have existed. The dorsal ver- tebrae are proccelous, and the anterior trunk-ribs are double- headed. There is a broad sternum with a median ridge 01 keel, and ossified sternal ribs. The jaws were always armed. Fig. 177.—Pterodaciylus hrevirostris. Skeleton and restoration. with teeth, and these were implanted in distinct sockets. In some forms {Ramphorhynchus) there appear to have been no teeth in the anterior portion of the jaws, and these parts seem to have been sheathed in horn, so as to constitute a kind of beak. A ring of bony plates occurs in the sclerotic coat of the eye. The pectoral arch consists of a. scapula and distinct coracoid bone, articulating with the sternum as in Birds, but no clavicles have hitherto been discovered. The fore-limb (fig. 177) consists of a humerus, ulna and radius, carpus, and hand of four fingers, of which the inner three are short and un- guiculate, whilst the outermost is clawless and is enormously elongated. Between this immensely - lengthened finger, the side of the body, and the comparatively small hind-limb, there must have been supported an expanded flying-membrane or " patagium," which the animal must have been able to employ as a wing, much as the Bats of the present day. Lastly, most of the bones were " pneumatic "—that is to say, were hollow and filled with Please note that these im
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