Chap. XVI. CHINCHONA-PLANTS OF CARAVAYA. 271 



in the open plain. A tree of tins variety yields six or seven 

 quintals of bark, while the Calisaya fina only yields three or 

 four quintals ; and Gironda declared that he had seen one, 

 in the province of Munecas in Bolivia, which had yielded 

 ten quintals of tabla or trunk-bark alone. 



My remarks respecting the position of C. Calisaya trees, on 

 the sides of the ravine, only apply to the forest below Lenco- 

 huayccu ; above that position they are not found so high up 

 the sides of the mountains, probably owing to their greater 

 proximity to the snowy region of the cordillera. The nearest 

 snow may be about forty miles from Lenco-huayccu, as the 

 crow flies. "I also found that the Calisaya fina was most 

 abundant about the Yana-mayu, while the variety called 

 morada was plentiful in the upper part of the ravine. But it 

 was very difficult for an unpractised eye to detect the slightest 

 difierence between these two varieties, until their leaves were 

 placed side by side, when that of the morada appeared to be 

 just a shade darker green. Dr. Weddell has, in his work, 

 named the Calisaya morada, as a distinct species, C. Boliviana, 

 but I understand that he is now of opinion that it is scarcely 

 more than a variety of the Calisaya vera, its bark being veiy 

 generally collected and sold as that of the latter. No plants 

 which I saw in the forests could be compared, for vigour and 

 regularity of growth, with the tree which I have already 

 described as having been planted on the edge of a clearing ; 

 and I think this tends to prove that plenty of Hght and air is 

 essential to the vigorous groAvth of the C. Calisaya, so long 

 as there is a sufficient supply of moisture, and protection 

 from the direct rays of a scorching sun for the first year or 

 two. The C. Calisaya is undoubtedly the most delicate and 

 sensitive of all the species of chinchona. 



Above the region occupied by C. Calisayas, in the forests, 

 is the third or upper zone, from 600 to 800 feet above the 

 river. Here, amidst very dense humid vegetation, covered 

 with ferns and mosses, are first met the trees of C. piibescens. 



