1 8 ROMANCE OF LOW LIFE AMONGST PLANTS. 



mention of the beautiful tree ferns is to be found in 

 the classic authors of antiquity, Theophrastus, Dios- 

 corides, and Pliny ; while reference is made to the 

 Indian trees, to the fig-tree which takes root from its 

 branches, and to palms. The first mention of tree 

 ferns is by Oviedo (1535). "Among ferns," says this 

 experienced traveller, " there are some which I class 

 with trees, because they are as thick and high as 

 pine-trees. They mostly grow among the mountains, 

 and where there is much water." After complaining 

 that the height is exaggerated, Humboldt goes on to 

 say that " in the CyaiJiea spcciosa and the Meniscium 

 of the Chaymas missions he observed in the midst of 

 the most shady part of the primeval forest that the 

 scaly stems of some of the most luxuriantly developed 

 of these trees were covered with a shining carbo- 

 naceous powder, which appeared to be owing to a 

 singular decomposition of the fibrous part of the old 

 leaf stalks." 1 



Between the tropics, where, on the declivities of the 

 Cordilleras, climates are superimposed in strata, the 

 true region of arborescent ferns lies between about 

 3200 and 5350 feet above the level of the sea. In 

 South America and in the Mexican highlands they 

 seldom descend lower to the plains than 1280 feet. 

 The mean temperature of this happy region is between 

 64° and 70° Fahrenheit. It reaches the lowest stratum 

 of clouds, which floats the nearest to the surface of 

 the sea and the plain, and it therefore enjoys unin- 

 terruptedly a high degree of humidity, together with 

 a great equality in its thermal relations. 



' Humboldt, " Views of Nature," p. 338. 



