H2 EVOLUTION IN THE PAST 



Remains of them have been found in Europe (Enaliornis) ; 

 but these do not indicate creatures of large size. In North 

 America some forms attained a length of nearly four feet 

 (Hesperornis). 



Whilst some birds had thus lost a long-neglected endow- 

 ment, others, suggestive of solan geese considerably under- 

 sized, had greatly improved their powers of flight. These, 

 as a result of long-continued flying habits, had gained a strong 

 framework for the wing, and also well developed breast-bones, 

 with which to cleave the air and water (Ichthyornis}. They 

 had by no means grown out of affinities with reptiles to 

 the same extent as living birds. In addition to the presence 

 of teeth, connecting links remained in several parts of 

 the anatomy, notably in the vertebrae of the back- 

 bone, which were concave at both ends as were those of 

 early crocodilian forms. They were also, as were the 

 diver-grebes, small-brained creatures for the size of their 

 bodies. 



Other birds derived from the same stock as the semi- 

 solans were modernised, especially in being toothless. Some 

 apparently were a complication of storks and flamingoes 

 (Scaniornis) : others seem to have been forerunners of 

 cormorants (Graculavus). Other forms had descended from 

 a different stock. Some of these were rail-like birds (Telma- 

 tornis}, some possessed close affinities with the dunlins 

 of our time (Palceotringa). Doubtless many birds of 

 various kinds haunted the inland valleys and plains, but 

 their remains have perished, or at least have not been dis- 

 covered. 



VEGETATION The sylvan scenes of the early Cretaceous presented for 

 the most part much the same aspect as those of the Jurassic. 

 Sequoia firs were represented by primitive forms of the 

 " big tree " (5. gigantea), and the " red- wood " (5. semper- 

 virens). And these and other conifers, as well as ferns and 

 cycads, extended far and wide, with as yet no serious com- 

 petitors to dispute their long-held territories. 



ANGIOSPERMS But in some unknown regions possibly in the far north- 

 east of the North American continent shrubs and trees of a 

 different character must for a long time have been developing. 



