OF THE PERUVIAN ANDES. 3 



Peru is in most parts withia less than 100 miles of the sea-coast, 

 and the flora suffers in consequence from the deficient supply of 

 moisture, and is poorer both in individuals and in species than 

 in tlie plateau region, which is better watered. On this subject I 

 fouud, however, reason to modify somewhat the statements of 

 ■writers of autliority which are summed up in the 20th chapter of 

 Grisebach's great work on the ' Vegetation of the Earth.' 



The distance from Lima to Chicla is little over 70 miles ; but as 

 the former stands only 468 feet above the sea, and Chicla at the 

 level of 12,220 English feet, the ascent surpasses in height and 

 steepness anything hitherto accomplished by railway engineers. 

 Eor a distance of about 24 miles the valley slopes upward very 

 gently, and to a person travelling, as I did, at the latter end of 

 the dry season, the appearance of the surface is that of absolute 

 sterility, except along the banks of the Rimac, or along rare 

 irrigation channels. The land is not, however, absolutely devoid 

 of vegetation; some small Amarantacece (Alternantheray Telan- 

 thera)^ the cosmopolitan JPortulaca oleracea^ Heliotropium parvi- 

 florum^ Hoerhavia viscosa, Franseria amhrosioides^ and one or two 

 other unattractive flowering plants, occur here and there, and 

 prove that tlie climate here is not so absolutely dry as it is in 

 southern Peru and northern Chili, where the high range of the 

 Andes is more distant. 



As the valley becomes gradually narrowed between the project- 

 ing ridges of the mountains, appearances of vegetation rapidly 

 increase. Cactoid plants (apparently belonging to three species 

 of Cereus) and the nearly withered stems of a large Bromeliaccous 

 plant (^Pnya ?) are seen on the rocky slopes, which are furrowed 

 by channels cut by running water; and about San Bartolome, 

 nearly 40 miles from Lima and 5000 feet above the sea, a tinge of 

 green on the declivities becomes perceptible even at this season, 

 and a slight trickle of water may be noted in some of the lateral 

 ravines. Flowering plants, especially Comf08it(B of the genera 

 Tessariuy Saccliaris^ Viguiera, JEncelia^ SidenSy Sf^-i show them- 

 selves in the bed of the valley, but the species are for the most 

 part the same that are seen in irrigated places near the coast. 

 At Surco, 6655 feet above the sea, are some gardens in which 

 tropical fruits (Anona Chemnolia, bananas, granadillas, &c.) are 

 succest^fuUy cultivated. Up to this point it would appear that 

 the change of climate, so far as regards temperature, must be very 

 slight. The decrease due to increasing elevation is compensated 



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