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 imder 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 tlie moss and lichen, even in the 

 deep shade of the forest, where no direct light ever penetrates, liourish 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? 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. 



W^e m\ist 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 heal 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- 



