G HABITAT OF THE CINCHONAS. 93 
opinion of the bark collectors, however, a proportionately cooler 
location, extending to the uppermost boundary of forest vegetation, 
favors the formation of alkaloid. A considerable exposure to direct 
sunlight appéars to be injurious to young plants, but decidedly 
favorable to strongly developed trees, and particularly also to 
increase the brightness of color of the bark, which in commerce is 
so highly prized. 
As the precise habitat of the Cascarilla fina, the best cinchona 
bark, Karsten* unhesitatingly designates the foggy region of the 
Andes chain, which is intercepted by deep valleys, with a mean 
temperature of 12 to 13° C. (53.6 to 55.4 F.), where, through nine 
months of the year, rain prevails, and an actual alternation of sea- 
sons occurs to so slight an extent that the Cinchonas continually 
bear flowers and fruits. The lower region, in which already a dry 
season may be distinguished, contains chiefly large-leaved cinchona 
trees of less medicinal power, together with the worthless “ Casca- 
rillos bobos.” 
From the dimensions already stated it is manifest that the Cin- 
chonas belong to the medium and higher forms of the tropical 
primeval forest, but are, however, overtopped by the far more 
mighty representatives of the Artocarpez, Lecythidee, Sapindacez, 
Terebinthacez, the palms, and many others. 
The richness of the tropical flora excludes a uniform constituency 
of the forest, and accordingly the Cinchonas also live mostly dis- 
persed, at the most, forming here and there smaller groups, which 
in the distance are discriminated more by a particular color than 
by a striking arrangement of the complete picture of the primitive 
forest. Such spots (manchas) in the variegated carpet of the 
crowns of foliage are espied by the disciplined eye of the bark col- 
lector (cascarillero) at the remotest distances,’ even at a time when 
they are not decorated by the rich flower clusters. 
Extended groups of C. corymbosa, which almost deserve the 
name of cinchona forests, were met with by Karsten} on the 
boundary of New Granada and Ecuador, on the western declivity 
of the volcanoes Cumbal and Chiles. 
The Cinchonas may always be designated as a very remarkable 
member in the vegetative dress of their surroundings, so that the 
portion of the South American mountain regions inhabited by 
1 Medicinische Chinarinden Neu-Granadas, p. 12-13. 
? Weddell, His¢. nat. fol. 9. 10; also Wellcome: ‘‘A visit to the native Cinchona forests 
of South America,” Proceedings of the American Pharm. Association (1879), 814-830; 
reprinted in the Pharm. Journ. X (1879), 980, and abstracted in Just’s Botan. Jahresbe- 
richte, 1880. : 
* Medic. Chinarinden, p. 20. 
