450 



The Flying Lizards of the Secondary Rocks. 



in order to descry their prey at long- or snort distances. These 

 bony plates also assist to maintain the prominent position of the 

 front of the eye, which is so remarkable in birds/'* 



The oldest known Pterodactylous remains appear to have 

 been obtained from the Upper Keuper of Wurtemberg, but they 

 are of only a fragmentary nature. The Dimorphodon fPterodac- 

 tylusj macronyz, Buckld., from the Lias of Lyrne-Regis, is the 

 oldest found in this country. In this species there is an unusual 

 provision for giving support and movement to a large head at 

 the extremity of a long neck, by the occurrence of bony tendons 

 running parallel to the cervical vertebras, like the tendons that 

 pass along the backs of many birds, and those figured in the 

 tail of Rhamphorlnjnckus. The expanse of the wings of this 

 creature equalled those of the Rhamphorhynchus, but its jaws 

 were eight inches long, and it is not supposed to have had a 

 long tail. Beside a few large, long, and sharp-pointed teeth 

 at the fore part of the jaws, it was furnished with a close-set 

 row of short, compressed, very small, lancet-shaped teeth. 



Fragmentary remains of Pterodactyles also occur in the 

 Stonesfield slate of this country (one of the Oolitic series), and 

 there is evidence of the existence of the same genus in the 

 Wealden strata, but the species must have been of a larger size. 



It is in the cretaceous series of England that the most 

 gigantic specimens of flying lizards have been met with. 



We are indebted to Lucas Barrett, Esq., F.G.S., the present 

 director of the Geological Survey of the West Indies, and Jas. 

 Carter, Esq., M.E.C.S., of Cambridge, for the discovery of 

 remains of Pterodactyles in the Cambridge Greensand. 



These bones, which always occur detached and much broken 

 and water- worn, present, in the restorations of Professor Owen, 

 proportions so gigantic that I cannot do better than quote his 

 own calculations upon the subject, extracted from No. 1 Sup- 

 plement to Pakeontological Society's Memoirs for 1859, "Fossil 

 Reptilia of Cretaceous Formation.'" 



Dimensions of Pterodactylus SedgivicJai, Owen, Greensand, 

 Cambridge : — 



" Humerus 

 Radius 



Metacarpus 

 1st Phalanx 

 2nd „ 

 3rd 

 4th 



Feet. 



Inches 



1 







1 



4 



1 



8 



2 



o 

 O 



1 



9 



1 



5 



1 



1 



Total of one wing 



10 



* Yarrel On the Anatomy of Birds of Prey. Zool. Journal, vol. iii., p. 181. 



