4 REPOET OX TWO BOTANICAL COLLECTIONS FROM 



All this sandstone area belongs to the oldest land of South America : against the edge 

 of it the Andes were heaped up — newer land which grew to its present form in the 

 tertiary period, and formed a link of high ground round the head of the then existing 

 Amazon valley. 



It is significant to us that the chief mountain-systems of South America outside 

 the Andes reach very similar heights and similarly stand more or less parallel to the 

 nearest coast, whence the trade-winds bring an abundance of rain. These mountain- 

 systems are three : (1) the Coast Andes of Venezuela, of direct eruptive origin, but 

 continued eastward from Caracas in the lesser sandstone mountains of Caripe; (2) the 

 Parime mountains with Roraima at the eastern end and Duida at the western end ; 

 and (3) the mountains of South Brazil formed of schists tipped at a high angle. 



Coast Andes. 



Niaguata 9125 feet. 



Silk of Caracas 8741 „ 



Taraava 8052 ., 



Heights * north of the Equator. 



Parime .Mountains. 



Roraima 8740 feet. 



Duida 8278 „ 



[Peaks near Duida estimated at 10,000 feet.] 



Height** in South Brazil. 



Itatiaia 8999 feet. 



Organ Mountains 0609 „ and more. 



Serra da Caraya . 041 1 „ 



Itambe ... 5900 feet. 



Serra da Piedada 5874 „ 



Itaeolumi 5700 ,, 



Unlike in geological structure the three systems are unlike as well in their relation 

 to the Andes. The Casiquiare, by uniting the Orinoco and Amazon, encircles the Parime 

 mountains, and the undulating country of little elevation to the west of it effectually 

 separates this system from the Andes ; the plains of Matto Grosso, &c, wherein rise 

 within a few miles of each other the Paraguay and Madeira, to flow the one north, the 

 other south, separate the Brazilian mountains and the Andes ; but the Venezuelan coast- 

 range is most intimately bound to the Andes proper through the Cordillera of Merida. 



Spanish settlers in the New World soon came to recognize a belt on the mountains of 

 the tropics suited to their needs and for the growth of their food-plants. They called it 

 the temperate land — " tierra templada," — and the range of its mean annual temperature 

 may be set down as 15°-20° C. (59°-77° F.). Above the " tierra templada" is the "tierra 

 fria," below it the " tierra caliente." 



The limits of these belts depend on exposure. In the Venezuelan mountains, according 

 to Sievers (' Venezuela,' p. 2G), the " tierra fria " extends from about 7200 feet upwards ; 

 among the Great Andes it sometimes commences as high as 10,000 feet ; on Roraima 



* The heights of the Coast Andes are taken from Sievers's ' Venezuela' (Hamburg, 1888), pp. 277, 278 ; those 

 of Duida and neighbouring peaks from Sir Robert Schomburgk's narrative in Proc. Roy. Geogr. Soc. x. 

 1840, p. 245; and those of the Brazilian mountains, Itambe excepted, from Liais, ' Climats, Ge'ologie, Faune 

 et Geographie botanique du Bresil' (Paris, 1872), pp. 45-49. Most astounding are the erroneous statements 

 published regarding the altitudes of the Brazilian mountains ; for instance, the Serra dos Pyrenaos, estimated 

 previously to reach 9700 feet, proves to be no more than 4543 feet (G'ruls, ' Relatorio da Commisao exploradora,' Rio, 

 1894, p. 26). 



