228 REPTILIA. 



very stout metacarpal and four much-elongated phalanges, the last slender 

 and tapering to a point. The pubis is small and club-shaped and attached 

 to the ischium only by its slender end. The phalangeal formula of the 

 hind foot is 2, 3, 4, 5, 2, each of the first four digits normal and bearing a 

 large claw, the fifth digit opposable, with very short metatarsal, one long 

 proximal phalange and an attenuated distal phalange. The only known 

 species is Dimorphodon macronyx, with skull attaining a length of about 

 0'2 m., from the Lower Lias of Lyme Regis, Dorsetshire. 



Fm. 139. 



Bhamphorhynchus phyllurus ; restoration by 0. C. Marsh, showing the extent of 

 the volant membranes, one-seventh nat. size. U. Jurassic (Lithographic 

 Stone) ; Bavaria. 



Bhamphorhynchus (fig. 139). Another long- tailed Pterodactyl, with 

 much-elongated head, very large eye, very small antorbital and narial 

 vacuities. The long axis of the quadrate is inclined downwards and 

 forwards. The jaws bear large, irregular teeth, pointing forwards, but 

 not extending quite to the anterior end of the jaws, which seem to 

 have terminated in a short beak. The sacrum comprises 4 vertebrae, 

 and the tail, strengthened by ossified ligaments, sometimes exhibits 

 nearly 40 vertebrae. The keel of the sternum extends forwards as a 

 slender process, and the scapula is usually fused with the coracoid. 

 The pubis is a slender bar, bent approximately at right angles, not 

 expanded where it meets its fellow of the opposite side, but fused with 

 its fellow at this symphysis. The limbs much resemble those of 

 Dimorphodon, except that the fifth digit of the hind foot is smaller than 

 the others and comprises three phalanges. One specimen, named Rham- 

 phorhynchus phyllurus, exhibits impressions of the wing-membrane to the 

 extent shown in the accompanying restoration (fig. 139). The typical 

 species is Rhamphorhynchus longicaudatus, from the Lithographic Stone 

 (Lower Kimmeridgian) of Bavaria. All the satisfactorily known species 

 have been obtained from this formation in Bavaria and Wiirtemberg, and 

 the largest (R. grandis) has a skull about - 2m. in length. 



