384 RYE—OATS—POTATOES. 
Rye and barley, which resist cold better than 
wheat, are cultivated on the highest regions, but 
only to a small extent. Oats do not answer well in 
New Spain, and are very seldom seen even in the 
mother-country, where the horses are fed on barley. 
The potato appears to have been introduced into 
Mexico nearly at the same period as the cereal grasses 
of the Old Continent. It is certain that it was not 
known there before the arrival of the Spaniards, 
at which epoch it was in use in Chili, Peru, Quito, 
and New Grenada. It is supposed by botanists, 
that it grows spontaneously in-the mountainous re- 
gions; but our author asserts that this opinion is 
erroneous, and that the plant in question is nowhere 
to be found uncultivated in any part of the cordil- 
leras within the tropics. According to Molina it is 
a native of all the fields of Chili, where another 
species, the Solanum car?, still unknown in Europe, 
and even in Quito and Mexico, is grown ; and M. 
Humboldt seems to consider that country as the ori- 
ginal source of it. It is stated that Sir Walter Ra- 
leigh found it in Virginia in 1584; and a question 
arises, whether it arrived there from the north, or 
from Chili, or some other of the Spanish colonies. 
Our traveller seems to consider it not improbable 
that it had been conveyed from some of the Spanish 
colonies by the English themselves. 
The plants cultivated in the highest and coldest 
parts of the Andes and Mexican cordilleras are po- 
tatoes, the Txopceolum esculentum, and the Cheno- 
podium quinoa. The first of these are an important 
object in the latter country, as they do not require 
much humidity. The Mexicans and Peruvians 
preserve them for a series of years, by destroying 
their power of germinating by exposure to frost, and 
