256 The American Naturalist. [March, 
geologically resembling the western range. The waters of the Laca- 
tunga basin flow south and burst through the eastern range. The 
drainage of the basins of Quito and Ibarra goes to the Pacific. The 
western cordillera, by the Quito basin, is quite low, not more than 
10,000 feet, but is raised by superimposed voleanic rock into the lofty 
volcanoes of Corazon, (15,804), Atacoza, (14,390) and Pichincha. The 
eastern cordillera is here more complicated, and bears the giant volca- 
noes of Cotopaxi (19,480), Sincholagua (16,360), Antisana (18,885) 
and Cayambe (19,450). Northward the eastern range is continued 
into Columbia, increasing in height and breadth, but without any vol- 
cano north of Cayambe. In the province of Quito the western range 
rises into the volcanoes of Cotocachi (16,295) and Yanaurai (14,000.) 
Both Dr. Wolf and Mr. Whymper describe travelling in the Ecua- 
dorian Andes as depressing in the extreme. The lower regions, up to 
ten thousand feet, are thickly covered with a forest, within which it 
rains forever, the home of fever and dysentery. The higher regions 
are relatively healthy, but past expression dreary, all the more or less 
rounded heights being covered with coarse brown olive paramo grass, 
and presenting quite a contrast to the picturesque ruggedness of the 
Alps. These bleak paramos, as the tracts 10,000 feet or more above 
the sea are called, are poorly populated and badly tilled, while the huts 
are windowless and the people in rags. Here and there are fertile val- 
leys with forest in sheltered spots. The temperature has little 
variety, ranging from 39° to 46°. 
Mr. Whymper describes the climate of the paramos as a perpetually 
wet afternoon, and speaks of Chimborazo as a long extinct volcano, 
and states that the existing centres of volcanic activity are Cotopaxi 
and Sangai. The whole of the Andes of Ecuador are, according to 
Dr. Wolf and Mr, Whymper, situated more to the east than they are 
shown on Humboldt’s and other maps. 
THe Ucayaur—The Ucayali, generally considered the leading 
affluent of the Amazon, has been found to be navigable for 1040 miles. i 
The junction of the Perene with the Ene forms the Tambo, and that 
- of the Tambo with the Urubamba forms the Ucayali. The Perene, 
which curves westward toward the Andes, can be navigated ten miles 
above its junction with the Ene, while the Huallaga, a large tributary 
` tothe north, can be entered by large steamers to 100 miles from its 
mouth. {daiis on the Amazon, on the frontiers of Peru and Brazil, 
is 350 feet above sea level, the mouth of the Ucayali 370, that of the 
` Tambo 800, and that of the Ene 1000 feet. ‘The native population of 
