190 
THEORETICAL AND PRACTICAL HUSBANDRY. 
to supply without waste, to cheapen the product by the expenditure of the least labor, and 
restricting the food to the kind and quantity, so that it shall not be lost by escaping into 
the air, or being washed to remote parts by rains. It is evident that adjustments require 
a complete insight into the physiology of vegetation—its incipient stage, its maturing 
strength, the peculiar or special products to be formed, the elements composing them, and 
the best form in which these elements should be combined to meet all the wants of the being. 
As I have already said, functional endowments must be considered ; hence to pursue that 
course with a plant which will give it an early vigorous constitution, a full development of 
its organs in its first stages, and the foundation is laid for the full amount of the products 
sought. 
The conditions required for a vigorous and healthy vegetation are quite various. As 
there are animals who feed upon the tobacco plant, poisonous mushrooms, the mucila¬ 
ginous leaf, decaying wood, and the glutinous starchy cereal, so there are those who live 
in boreal regions, others under the tropical sun; some in clear, others in muddy waters, 
some in pestiferous marshes, some in dry and burning sands. The conditions of life, 
though they require a wide range, yet they are multifarious : to some, sunlight in its 
undecomposed form, is an essential circumstance to their perfect development; to others it 
is equally necessary that they should be stimulated only by the light modified by the green 
of the forest; the open and sunny day fades their colors and shrivels their organs, hence 
it would seem that these plants acquire their greenness by some other elements than by 
starch and chlorophyl. Our chemistry is here at fault; we know that the maize or Indian 
corn can not grow in the shade, even in diffused light; it pines under the green light of 
forest trees, and grows too feebly to reproduce itself: but the moss and lichen, even in the 
deep shade of the forest, where no direct light ever penetrates, flourish and develop them¬ 
selves perfectly. This shows us that the economy of plants is not restricted as we have 
supposed. We can not say that all plants require sunlight, that it is only under the in¬ 
fluence of it that they assimilate the elements. It shows us too that the study of condi¬ 
tions is of the utmost importance. Where do we see, under the natural influences, organic 
beings acquiring perfect development, and where do we see them pine I Is it light direct 
or light reflected from green bodies which they want! or do they require the damp wood 
or the dry forest ? That condition in which we see development in the perfection of seed 
and fruit is the true one. 
We must not, however, consider plants as fixed and determinate in their wants ; they 
possess a flexibility of constitution which is often admirable. This fact, however, is more 
eminently so in some species than in others. Those most important to man as the indi¬ 
genous or the cereals, have no doubt a more restricted range ; they all require heat and 
light; some, as oats and barley, range widely as to latitude, and perfecting their seed 
in a few months. Rice, however, must germinate in flooded fields under a hot sun; its 
condition is restricted, while many marsh plants may be transported to the dry garden 
and flourish under the change. The side-saddle plant (Sarracenia purpurea) is a remarka- 
