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to Pasco, prefaced by some general observations on the 
climate of Chili and the western side of Peru. By bringing 
into one view a number of facts connected with the latter 
subject, some useful hints may be derived for the cultivation 
of plants from that part of the world; many species from 
thence being now common in our collections, and the number 
is constantly increasing, but their treatment is not always 
consistent with their natural habits. At the same time, as 
it is probable that the western side of South America will be 
more frequently visited by Europzean Botanists than formerly, it 
becomes a matter of some interest to know the best season of 
the year for exploring the different districts, especially where 
there is so much difficulty, at certain seasons, in travelling 
from one point to another. For want of previous informa- 
tion on this head, much valuable time has been lost by 
collectors arriving at different parts of the coast, when 
scarcely a plant was to be found in flower, and the weather 
would not allow of travelling in the interior. In the account 
of the road to Pasco, I will endeavour to give some idea of 
the sort of country that produced the few plants I was able 
to collect for you; but you are aware, that I was in very bad 
health during my stay in Peru, and my observations were 
necessarily very limited. 
Chili, and that part of Peru lying west of the Andes, froth 
their geographical situation and physical structure, offer an- 
interesting field for studying the effect of climate on vegeta- 
tion. The two countries present a line of coast, extending — 
from 40? of South latitude, to within a few degrees. of the 
, Equator; the great chain of the Andes runs in a direction 
almost parallel to the coast, and the surface of the inter- 
mediate country is similar throughout, consisting of ranges 
of mountains, diminishing in height as they recede from the 
Cordillera, These mountains are intersected by vallies 
nearly at right angles to the great chain, and consequently 
varying. little from due east and west, so that, while the 
coast is exposed to the action of those laws that regulate 
climate according to the difference of latitude at the level of — 
sea, the vallies afford an c tmd of tracing the 
