OE THE PERUVIAN A:N'DES. 27 



the great movements of alternate elevation and depression to 

 have been nearly contemporaneous throughout the vast length 

 of that range, and that it is more probable that some portions 

 remained as lofty mountain-masses, while otliers were nearly or 

 altogether submerged. This remark applies especially to the 

 highlands of Bolivia and Peru, where the Palaeozoic rocks do not 

 appear to be overlain by recent marine deposits. 



AVhether this view be valid or the reverse, we must, I think, 

 look to an adjoining region as the original home of the majority 

 of the special forms of vegetation that are now limited to South 

 America, as well as of many others that have spread more or less 

 widely to other parts of the eartli. In a zoological as well as a ^ 

 botanical sense Brazil is one of the most distinct and separate 

 regions of the earth. It is, in large part, a granitic region, from 

 which vast masses of superincumbent strata have beeu denuded, 

 and where the granite itself has undergone a great amount of 

 decay and ablation. We there see the ruins of one of the greatest 

 mountain-masses of the earth, where a very ancient fauna and 

 flora were developed, of which portions were able to migrate to a 

 distance, while others have been modified to adapt themselves to 

 the gradual changes of the environment. Many vegetable 

 groups which are but slightly represented in the higher region 

 of the Andes, but which doubtless originated in South America, 

 such, for instance, as the Melasfomacece, probably had their origin 

 in the mountains of ancient Brazil. 



If in the foregoing pages I have omitted to notice and discuss 

 the views of Professor Engler, expressed in his important work 

 * Versuch einer Entwicklungsgeschichte der Pflanzenwelt,' it is 

 because I felt that such a discussion would outgrow the proper 

 limits of the present paper. Agreeing in several of Professor 

 Bugler's hypothetical views, and entirely dissenting from others, I 

 could not do justice either to him or to myself without an amount 

 of detail which would be altogether inappropriate. 



