154 THE STORY OF THE EARTH. 



it. And since some fossils, like those of the Car- 

 boniferous limestone, obviously derived, have oc- 

 curred in the Neocomian beds of Upware, and in 

 the Cambridge Greensand (Fig. 31), it is probable 

 that the upheaval which brought about the forma- 

 tion of the Upper Greensand, raised the area of 

 ancient rocks beneath the (iault. It became too 

 shallow for the accumulation of anything but the 

 phosphatic products of marine animal and vege- 

 table life, boulders of the parent rocks, slates, 

 schists, quartzites, granites, of the neighbouring 

 land; and the multitudinous remains of Cimo- 

 liosaurus and [chthyosaurs, and Chelonians; to- 

 gether with true lizards, allied to the monitor; 

 and crocodiles of existing types. There are many 

 terrestrial saurians allied to the armoured Sceli- 

 dosaurus of the Lias, a score of Pterodactyls oi 

 all sizes of the genus Ornithochirus. One Ptero- 



dactyle, at least, is toothless. This type, which 

 has smooth jaws like the jaws of a bird, is named 

 Ornithostoma. The oldest known British bird is 



found in this bed. It is allied to the divers. 



Cretaceous Birds. 

 The oldest British fossil bird is found in the 



Cambridge Upper Greensand. The bones Indi- 

 an animal as large as tin* red-throated 1 ): 



ike the living genus Colytnbus\ 

 others show resemblances to Grebes and Cormo- 

 rants ; and possibly, in the hip girdle, to penguins. 



skull is singularly like that of the red-throated 



I > . < s ' and form, and t he joints ^i t he back- 



bon< nilar, but not identical. The femur, the 



thigh-bone, WSLS more than i* inch long; and the 



drui of the leg develops a process like 



