“ Bird life is abundant, and the bat family is well represented. Snakes, saurians, and turtles are met in great numbers at lower altitudes. Above 6000 feet in altitude there is a great diminution of animal life. In Ecuador there occur certain representative species of the southern Andes, such as the llama and the condor. Insect life also continues very abundant, and fish are found up to an altitude of 14,500 feet. In the Peruvian and Bolivian Andes on the Pacific side, the fauna, like the flora, is limited, but on the eastern or Brazilian slope is exceedingly rich. ”

“ Everywhere it presents a steep wall to the Pacific, and on the east it drops abruptly to the Amazon Valley; farther south, in Argentina, the land rises somewhat to meet it, and there are outlying ridges, but the main ascent is everywhere steep. The southern part of the system consists of a single range, with here and there outliers of comparatively little height, but from northern Chile and Argentina to Colombia, it consists of a high, broad plateau, capped by two or three ranges, with hundreds of high volcanic peaks, some active, others dormant or extinct. ”

“ In Colombia the palms and their associated tropical flora extend upward on the Andean slopes to an altitude of about 4500 feet, while above this is a mixed sub-tropical belt, extending to an altitude of nearly 10,000 feet, in which grow the cinchona, tree fern, and wax palm, and still higher up, at an altitude of 10,000 to 12,000 feet, the higher Andean bush growth, including the Andean rose; a species of bamboo also grows at these high altitudes. ”

“ The high land between the ranges is the best settled part of these sparsely settled countries, and the inhabitants of these elevated regions have some intercourse with the western seaboard, but very little with the low country to the east. But with the development of the mining industry in the mountains and the exploitation of the rubber resources of the upper waters of the Amazon, it may be expected that means of communication across the range will be improved in the near future. ”

“ The lower limit of perpetual snow, although an extremely indefinite line, varying from year to year with exposure and precipitation, has in general, in equatorial regions, an altitude of about 15,500 feet, but ranges a thousand feet on each side of this figure, being higher on the east and lower on the west side of the range. ”

“ Chile and Argentina. The broad, high plateau, with its bordering ranges and subsidiary eastern ranges of Bolivia, extends southward into these countries, gradually narrowing and decreasing in altitude, until in latitude 32° the Andes become reduced to a single range, except for spurs and outliers, most of which are of comparatively little importance. In the northern part the altitude of the ranges decreases greatly, Juncal, in latitude 26°, having a height of 17,530 feet, and Copaipó volcano, 19,700 feet. ”

“ Within the tropics the temperature ranges from 80° at the base of the mountains to 20° or less at their summits, a range due to altitude alone. Upon the Titicaca plateau Arctic conditions prevail, with frost every month of the year. Where the rainfall is copious, as it is on the eastern side within the tropics, the range of temperature between summer and winter is slight, while upon the west coast, in the same latitudes, where desert conditions prevail, the range is very great. ”

“ Farther to the south, in the region of less rainfall, the flora on the east and west sides of the Andes is quite different. On the west side, in lower Ecuador and Peru, the plant life is poor, and is that peculiar to a semi-desert region; but it extends up to high altitudes, lichens being found at 18,500 feet altitude ”

“ On the Bolivian slopes the fauna is much more abundant than in Peru. Further south on the Andean chain the fauna is less rich, and especially there is to be noticed the disappearance of the larger animals of the northern Andes. ”

“ The plateau of the Andes has here the greatest lateral extent and altitude in the entire system. The western range has an average altitude of 15,000 feet, while the Eastern, or Cordillera Real, is still higher, having peaks exceeding 20,000 feet ”

“ Las Damas and Peteroa are said to have been in eruption in the last century. The volcanoes grouped about Descabezado are quiescent, though appearances indicate recent eruption. Chilean ranges contain several vents, from which lava and ashes have been ejected in recent years. Autuco also has had eruptions within historic times. Farther south, Villarica volcano has frequently been seen in eruption, in all probability, other active volcanoes exist in the fiord region of South Chile, although none has yet been reported. ”

“ Its average height of 12,000 feet is subject to the same qualification. Following the coast, the system trends a little west of south through Colombia and Ecuador, but on entering Peru it turns to the southeast, in which direction it extends through that country and part of Bolivia. Through south Bolivia, Chile, and Argentina, its trend is nearly south, but it swings in a broad curve to the eastward near Magellan Strait. The mountain system rises abruptly on both sides throughout its course. ”

“ Many of the most prominent and highest ones have been mentioned; it remains to speak of those which are now active, or which have been active within historic times, and briefly describe their eruptions. ”