88 THE COMING OF THE BIRDS 



the bird became able to grind its food in its crop, and 

 thus dispense with the teeth. One of these birds of 

 the Chalk Period seems to have lost the power of 

 flight, so that we are not surprised that it has teeth. 

 It was a swimming bird, like the diver, about four 

 feet high. The other is a small flying bird; though 

 it has distinct teeth, in sockets, in its jaws. 



These belong, as I said, to the latter part of the 

 Age of Reptiles, when the climate was growing colder. 

 At the close of that period the flying reptiles perished 

 so completely that not a specimen is left in nature 

 to-day. The air was left to the birds and insects. 

 The warmth and abundance of food returned. The 

 outpouring of flowers fed the insects, and the vast 

 swarms of insects would feed the birds. The rocks 

 now show a great expansion and multiplication of 

 species, which we cannot follow here in any detail. 

 It is enough that our familiar birds begin to appear. 

 Ages before man came along there were owls and 

 parrots and many other types. There were still no 

 Arctic regions or Alps, remember; and warm-loving 

 birds could roam all over the earth. 



In order to throw a little further light on the bird- 

 world I will anticipate a little. For two or three 

 million years after the birds had taken undisputed 

 possession of the air the climate of nearly the whole 

 earth remained more than temperate. Monkeys lived 

 in what we now call England. Elephants browsed on 

 the low hills which are now the Dogger Bank under 



