civ PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [vol. lxxix, 



marshes and peat-bogs. A change in the geological background 

 had its reflex in the development of green foliage in place of the 

 almost leafless condition of the older plants, destined to live in 

 localities either physically or physiologically dry. 



Here^I must leave for the present the too ambitious subject, 

 which has been very inadequately treated. We have reached a 

 stage in the history of the plant-kingdom which in essentials per- 

 sisted until the latter part of the Carboniferous Period, when, in 

 correlation with a changed historical background, there was an 

 apparently sudden burst of energy, and new companies of actors 

 carried on the drama. With your permission, and if circumstances 

 permit, I will endeavour on a future occasion to follow the 

 development of plant-life through the closing scenes of the 

 Paheozoic Era, and, as far as it is possible to do so, consider the 

 relation of the succeeding Mesozoic floras, both to those which 

 preceded them and to the vegetation of the modern world. 



