Pterosauria
an order of flying Reptilia of Mesozoic age. No exoskele- PTOLEMÆUS PTOLEMY ton; dorsal vertebræ procœlous, anterior gest" that the earth was a fixed body, trunk-ribs double-headed; broad stertrunk-ribs double-headed; broad ster- remaining constantly at rest in the center of the universe, with the sun and nal ribs. Jaws generally armed with moon revolving round it as attendant teeth, implanted in distinct sockets . satellites. To account for the more com- The fore-limb consists of a humerus, plicated movements of the planets, a contrivance four fingers, the inner three unguiculate, planet revolved in a circle, while the cenwas devised by which each the outer clawless and enormously elon- ter of that circle described another circle gated. Supported by this finger, the round the earth. The Ptolemaic system PTERODACTYLS side of the body, and the comparatively short hind limb, was a patagium, or flying ing membrane. The bones were pneumatic.
PTOLEMÆUS, the dynastic name of 13 kings of Egypt, who reigned from 323 to 43 в. c. The most famous to 43 B. C. The most famous was Ptolemæus Soter, who reigned from 323 to 285 B. C. See PTOLEMY I.