BOTANICAL TRIP HITCHCOCK 345 



in all these cases is by sea, the isolated communities being served by 

 coastwise steamers. 



The Cordillera is broader than in Ecuador and consists, through 

 much of Peru, of two more or less distinct ranges. The valleys be- 

 tween are, in places, high broad plains or plateaus with an elevation 

 of 12,000 to 14,000 feet. There are numerous lofty peaks, several 

 more than 18,000 feet. The mountain region, especially the part 

 above tree line, is called the Sierra. The high plains and ridges 

 below snow line are called punas, puna corresponding to paramo in 

 Ecuador and Colombia. 



The forested slope to the east, the Montana, runs off into a com- 

 paratively uninhabited region as in Ecuador. But the subtropical 

 slopes and valleys in the foothills are highly cultivated. 



The climate of Peru is so varied that no general statement of 

 value can be given. The coastal plain is dry and comparatively 

 cool though tropical. The Montana is strictly tropical and for the 

 most part has a high rainfall. The Sierra is temperate and on the 

 high plateaus may be cold and bleak : 



The temperatures and rainfall for three places will give a good 

 idea of the climate in a general way. 



Lima on the coastal plain near sea level. Yearly average temper- 

 ature 19° (66° F.) ; average for August 15.9° (60° F.) ; average for 

 February 23° (73° F.). The average annual rainfall is 46 mm. (1.8 

 inches) of which 26 mm. (1 inch) fall in August and September. 



Arequipa, 7,500 feet altitude, on the Pacific slope of the Andes. 

 Yearly average temperature 13.5° (56i/2° F.) ; average for June, the 

 coldest month, 13.2° (551^° F.) ; average for October, the hottest 

 month, 14° (571/^° F.). The average annual rainfall is 147 mm. (6 

 inches) of which 142 mm. fall in January, February, and March. 



Cuzco, in the Sierra, at 11,000 feet altitude. Yearly average tem- 

 perature 10° (50° F.) ; average for July, the coldest month, 7.7° 

 (46° F.) ; average for November, the hottest month, 11.3° (521/2° F.). 

 The average annual rainfall is 980 mm. (39 inches). 



In the Montana of eastern Peru the rainfall rises to 100 inches. 



CITIES AND RAILROADS OF PERU 



Lima, the capital of Peru, is a fine city of about 225,000 inhabi- 

 tants and has many modern buildings. Callao, its seaport, with 

 about 50,000 inhabitants, is a few miles away, but the two cities are 

 now nearly continuous. Arequipa has a population of 55,000 and 

 Cuzco of 30,000. 



Aside from the railroads connecting small seaports with the 

 interior agricultural valleys of the coastal plain, there are two main 

 lines in Peru. These have been mentioned in a preceding para- 

 graph. The first goes from Callao to Oroya and on to Cerro de 



