THE NEOZOIC AGES. 259 



in the American Eocene are more like those of the 

 European Miocene or the Modern American flora, a fact 

 to which we must revert immediately. 



In Europe, while the Eocene plants resemble those 

 of Australia, when we ascend into the Miocene they 

 resemble those of America, though still retaining 

 some of the Australian forms. In the leaf-beds of 

 the Isle of Mull, — where beds of vegetable mould and 

 leaves were covered up with the erupted matter of a 

 volcano belonging to a great series of such eruptions 

 which produced the basaltic cliffs of Antrim and of 

 Staffa, — and at Bovey, in Devonshire, where Miocene 

 plants have accumulated in many thick beds of lignite, 

 the prevailing plants are sequoias or red-woods, vines, 

 figs, cinnamons, etc. In the sandstones at the base 

 of the Alps similar plants and also palms of American 

 types occur. In the Upper Miocene beds of (Eningen 

 in the Ehine valley, nearly five hundred species of 

 plants have been found, and include such familiar 

 forms as the maples, plane-trees, cypress, elm, and 

 sweet-gum, more American, however, than European 

 in their aspect. It thus appears that the Miocene 

 flora of Europe resembles that of America at pre- 

 sent, while the Eocene flora of Europe resembles 

 that of Australia, and the Eocene flora of America, 

 as well as the modern, resembles the Miocene of 

 Europe. In other words, the changes of the flora 

 have been more rapid in Europe than in America and 

 probably slowest of all in Australia. The Eastern 

 Continent has thus taken the lead in rapidity of 



