OP THE PERrVTAJS" ANDES. 7 



probably exceed tliat limit by nearly 1000 feet ; but I doubt 

 whether snow lies permanently on any of these summits. Com- 

 paring the rather scanty details given by Poeppig*, who followed 

 the more direct L'ne from Lima to Cerro de Pasco by Canta and 

 Culluay, I should infer that the character of the flora of the 

 western slope is there very similar to that of the upper valley of 

 the fiimac. 



In discussing the regions of vegetation in the Equatorial 

 Andes, M. Andre says that there is there no zone characterized by 

 the growth of alpine grasses, and that where these abound they 

 have occupied ground which, in a natural state, was covered by 

 shrubs and low bushes Avhich have been destroyed by fire. This 

 statement obviously refers to a zone considerably lower than that 

 which I saw above Casapalta, between 13,800 and 14,300 feet 

 above the sea. I do not believe that this can have ever supported 

 a vigorous growth of shrubs ; and, as regards the number of in- 

 dividuals, grasses undoubtedly took the first place, although here, 

 as everywhere In South America, the Composltse show^ed the 

 greatest variety of species. As happens in all high mountain 

 regions, they are Intermixed w^ith species of the characteristic 

 alpine flora, but the grasses give the dominant aspect to tho 

 vegetation. 



The most singular plant seen by me in the higher zone was a 

 member of the Cactus family, of which I am unable to find any 

 description. It forms large, low, cushion-like masses, several 

 feet, or even several yards, in diameter, completely covered by 

 long glistening silky white hairs which conceal the slender needle- 

 like sjnnes with which the whole plant is beset. At a little dis- 

 tance the plants were taken for patches of snow. Unfortunately 

 the specimen sent to Kew with a view to cultivation arrived in a 

 state of partial decomposition. 



It has been generally asserted, or taken for granted, by writers 

 of authority that the flora of the tropical Andes Is relatively poor 

 as regards variety of species. There is some reason to think that, 

 as compared with the highlands of Mexico, this idea is well 

 founded ; but I doubt whether it holds good on a comparison with 

 the floras of other high mountain regions. It mu^t be remem- 

 bered that the vast region included under the term Andes is still 

 most imperfectly explored by naturalists. Excepting, indeed, 

 the Audes of Central Chili, between the 32nd and 37th degrees 



* Eeise in Chili und Peru, vol. ii. 



