12 The Origin of the 



portion of chalk at least was not formed under the 

 sea ; I have also the distinct impression in chalk of 

 a piece of wood. But these may be regarded as 

 comparatively trifles, when we are informed that it is 

 in the cretaceous period that the monotonous 

 vegetation of the older style is replaced by the more 

 beautiful and varied forms of our modern woods. 



" In Europe," writes Dr. (now Sir J. William) 

 Dawson, " in the lower part of the Upper Cretaceous 

 of Bohemia, have been found some leaves which 

 indicate the beginning of this change. These have 

 been referred to Caesalpinias or Brasilettos, pod- 

 bearing trees of India and tropical America, Aralias 

 or Ginsengs, Magnolias, Laurels, an Ivy, and a 

 peculiar and uncertain genus (Credneria.) With 

 these are noble palms, both of the types with pinnate 

 and palmate leaves, and trees allied to the Giant 

 Sequoias of California, and to the Araucarian pines 

 of the southern hemisphere. These ancient 

 Cretaceous forests of Eastern Europe are compared 

 by Saporta with those which now live in the warmer 

 portions of China or in South America, — truly a 

 marvellous change from the sombre and uniform 

 vegetation by which they seem to have been imme- 

 diately preceded. A still further development of 

 modern vegetation takes place in the next or highest 

 member of Cretaceous, the Maestricht beds 

 (Senonian), where we find a crowd of modern types. 

 On this great change, Count Saporta remarks with 

 truth that there seem to have been periods of pause 

 and of activity in the introduction of plants. The 

 Jurassic period was one of inactivity ; and a new and 

 vigorous evolution, as he regards it, is introduced in 

 the middle of the Cretaceous. 



" This new and grand elevation of the vegetable 



