of the Cacti in Brazil. 391 



The Cacti do not appear particularly affected by the different 

 degrees of currents of air. It is well known that they are found 

 near the sea, as well as on high mountains, where they grow 

 abundantly wherever they have a sunny situation, and a clear 

 and dry atmosphere; and where the glass is always a few 

 degrees above the freezing point. They are found in Brazil, 

 close to the sea, and on islands that have never been overflown 

 by it, above the line where vegetation ceases ; and many species 

 of Cerei are found on the dry hard sea shore. Most of the 

 Opuntiae are found more in the interior of the country, at a 

 height of from 500 to 1500 and 2000 ft. above the level of the 

 sea, and the Melocacti are also found high up the mountains. 

 An attentive observer may perceive that in our gardens many 

 species of Cacti require a variation of temperature, particularly 

 during the winter months. Those who have such plants from 

 Malpays, and the other warm districts of the Tierra caliente of 

 Mexico, from the narrow hot valleys of New Granada and 

 Peru, or the sea coast of Brazil, may observe that they fre- 

 quently become sickly when they are exposed to a change of 

 temperature of + 6° or 8° Reaum., while others, which are natives 

 of high plains and of mountains, are much less susceptible. 



Having made these general observations, allow me more par- 

 ticularly to add what I have had an opportunity of observing 

 respecting the extension of the Cacti in Brazil. In the province 

 of Rio Janeiro, which for the greater part is mountainous and 

 covered with forests, I have only found species of the genera 

 Cereus and Opuntia on the sea shore, and on dry high-lying 

 places. They were tolerably numerous, so that they gave a very 

 peculiar character to the landscape. The latter is used as a 

 hedge for enclosures. The species, on the contrary, belonging 

 to the division Epiphyllum Herm. (Cerei alati De Cand.) are 

 very abundant in this tract of land, and ornament the trees of 

 the forests, and the mossy rocks of the so called Organ Moun- 

 tains (Serra des Orgaos), with their splendid-coloured flowers. 

 Farther towards the south, in the province of San Paulo, the 

 jamacaru (Cereus Jamaracu Dec.) is very much cultivated in 

 gardens, and also in dry fields. It forms a stem 30 ft. high, and 

 is highly valued by the natives on account of its edible fruit. 

 In this province, and in that of Minas, there are several species 

 of the genus Mammillaria, though they are but few in number 

 compared with those above mentioned, because this genus ap- 

 pears to me properly to belong to Mexico. That part of the 

 province of Minas which, in its vegetation, corresponds with the 

 western territory of Espirito Santo and Porto Seguro, and which 

 is partly shaded by thick and humid forests, and is the native 

 place of the white topaz, the aquamarine, and the chrysoberyl, 

 can produce but few specimens of the Cacti ; but further to the 



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