Extension and Use of the Cacti. 1 55 



94° for the native country of this family. The distribution of the genera 

 throughout this extensive range will be treated of hereafter. 



The height at which they grow above the level of the sea is ascertained in 

 many situations, but, unfortunately, Hooker does not mention how high 

 Douglas found Cacti in 44° north latitude on the Rocky Mountains ; but, from 

 all appearances, we may at least conclude that the height must be about 

 3,000 ft. The most considerable southern elevation given by Meyen is 

 5,000ft. under 34° south latitude; and by Poppig, nearly 9,000ft. under 

 33° in Chile. The elevation in Peru is given by Meyen, in which, on 

 the enormous table-land on the Lake of Titicaca, the Cereus and Pereska'a 

 grow; and near the town of Ehuquito, 16° south latitude, according to Pent- 

 land, they are found at a height of 13,000 English feet; and in the Cordilleras 

 of Tacua, more to the south, nearly under 18°, he states that the wonderful 

 dwarf-like Pereskza is found still higher, viz. nearly 500 ft. below the limit of 

 eternal snow. A. von Humboldt gives the like information for Quito. At 

 the foot of the Chimborazo, near Riobamba, he observed upright torch thistles 

 ( Cereus sepium H. B. & K.) at a height of 1,480 fathoms, therefore nearly 

 9000 ft. Von Martius observes that in Brazil the Cacti grow to the tops of 

 the chain of mountains, which, without them, would be proportionably low ; 

 and Baron von Karwinski found some Mammillariae and small short-jointed 

 Cerei in Mexico, near San Joze de Loro, on the top of the Cerro de la 

 Vinda, at a height of 11,000 ft. above the level of the sea. 



The amazing extent of the distribution of this family naturally occasions a 

 great variety in the localities ; of particular species. It must, however, be 

 observed, that, with the exception of the cultivated Opuntiae and Cacti, all the 

 other species are confined to small localities, and that, therefore, information, 

 such as that given by Meyen, of the appearance of the Mexican Cereus senilis 

 on the Andes in Chile, was probably supposed to be incorrect, from want of 

 such information. The under strata of the soil seem to be various, as I have 

 found particular species on chalk, sandstone, primitive rock, and on volcanic 

 remains, porphyry, &c. They are generally at a distance from the sea coast, 

 where the soil is not impregnated with salt ; yet Moritz found a great number 

 of Cacti, and even Melocacti, near La Guayra, not far from Caraccas, close to 

 the sea shore, among the tufts of Coccoloba uvifera, jHippomane Mancinella, 

 &c. &c. A similar remark was made by Baron von Karwinski on Cuba, 

 where the Cereus baxanus, a new species nearly allied to C. grandiflorus, and 

 some Opuntiae, were found growing in abundance in company with the common 

 plants on the sea shore. Particular species in the interior of the country seem 

 to prefer somewhat the same kind of soil ; as they, with the exception of the 

 Pereskitf, grow in sunny open situations ; and they seem to get sufficient 

 nourishment from the poor soil, and even thrive on heaps of stones, on loose 

 sand, or in the narrowest chinks of the rocks. The former is particularly the 

 case with the tree kinds of Cereus and Opuntia, in the low-lying parts of the 

 country ; and all travellers agree that the districts where such forests of 

 Cacti grow are exceedingly barren, and almost destitute of other plants. 



It is different with the species of the more temperate regions. The Mam- 

 millaria and Echinocacti of Mexico grow, according to Baron von Karwinski, 

 on a loamy, but by no means unfruitful, high plain, among low grass, and only 

 sometimes in the crevices of rocks, &c. Those species, also, which grow on 

 the Alps, grow in good soil, although they have a most miserable appearance. 



It is an error to suppose that all the Cacti prefer dry situations. It may 

 certainly be the case with the large Cardones of the warm valleys, but it is not 

 so with many of the very numerous species of the Tierra templada. Those, 

 for example, in Mexico, have five months of continued rain, viz. from June to 

 October, but stand the other seven months of the year quite well, in a per- 

 fectly dry state; a circumstance which, in the culture of the Mammillariae and 

 Echinocacti, should be particularly attended to. 



It is evident, from the degrees of latitude and the elevations of the localities 

 in which the different species grow, that the temperature must be very various. 



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