GERMINATION. 17 
any given locality, such as the qualities of the soil, the degree of moisture both of 
the earth and skies, the inclination of surface, rocks, shades, and winds, the com- 
bined action of which often becomes an exceedingly complicated matter. Now 
to each of these innumerable combinations of circumstances, the Creator has 
adapted the constitution of certain species of plants, so that each given locality 
may be expected to produce its own appropriate kinds. But since some species 
are also endowed with the power of accommodating themselves to a wide range 
of circumstances, these are found more extensively diffused, while others, without 
this power, are comparatively rare. 
15. Vegetation is susceptible of important changes by culti- 
vation. Many plants are improved, in every desirable quality, 
by accommodating themselves to the conditions of soils enriched 
and enlivened by art. Examples are seen in almost every cul- 
tivated species. 
16. The cabbage, in its wid state, is a slender, branching herb, with no appear- 
ance of a head. The potatoe, in its native wilds of tropical America, is a rank, 
running vine, with scarcely a tuber upon its roots. All the rich and delicate 
varieties of the apple have sprung, by artificial means, from an austere forest- 
fruit. The numerous and splendid varieties of the Dahlia are the descendants 
of a coarse Mexican plant, with an ordinary yellow flower, of a single circle of 
colored leaves. The tulip and the geranium afford similar examples. 
17. Changes, not only in the qualties of vegetation, are ef- 
fected by culture, but also in the species themselves, through the 
substitution of the useful or the ormamental for the native pro- 
ducts of the soil. Thus, in agricultural districts, almost the 
waole face of nature is transformed, by human skill and industry, 
from the wilderness to the fruitful field. 
a. Hence it appears that there is scarcely a spot on earth which is not caused, 
by the quickening energy of the Creator, to teem with vegetable existence, in some 
of its numberless forms, while his goodness is conspicuous in rendering those 
tribes which are most subservient to the wants of man capable of the widest dif- 
fusion. 
