CHAP, ii.] THE LOWER EOCENE PLANTS AND ANIMALS. 25 



The Rivers. 



Since the higher grounds in Great Britain in the 

 Eocene time were in their present positions, it will 

 follow that the watersheds of the principal rivers were 

 then very much as they are now, so far as relates to 

 their upper courses. On the western side of the Pennine 

 mountain axis the Kibble, Mersey, Dee, and Severn fell 

 then, as now, into the Atlantic, after traversing the 

 broad valleys reaching to the line of cliffs off the west 

 of Ireland. Those on the east fell into the south-eastern 

 sea (see Map, Fig. 3), probably joining some of those of 

 Norway, and contributing to form the great river which 

 was the chosen haunt of the alligator and the crocodile, 

 and which flowed through the dense forests of palms 

 and banksias, then covering the Eocene continent in 

 these latitudes. The lower course, however, of the 

 Trent was determined by movements of level, which 

 took place in Post-meiocene times, and the river Thames, 

 as Professor Eamsay has pointed out, came into being 

 also after the close of the Meiocene age. 



The Lower Eocene Plants and Animals. 



The lower Eocene vegetation * in Britain preserved in 

 the London Clay was, as Professor Heer observes, of a 

 tropical and Indo-Australian character. The forests 

 were composed of palms of various sorts (Palmacites, 



1 Bowerbank, Hist. Fossil Fruits and Seeds of London Clay, 1840. 

 Heer, Climat et Vegetation du Pays Tertiaire, transl. Gaudin, 4to, p. 172. 

 For a further account of the Lower Eocene flora, the reader may be 

 referred to a forthcoming work by Messrs. Starkie Gardner and Ettings- 

 hausen, in the Palseontographical Society's publications. 



