FARMERS' INSTITUTES. 231 



tiiict species of grasses have been found growing on a single rod of English turf. 

 Is this variet}- of any use and importance? We answer yes, for the entire ani- 

 mal kingdom subsists either directly or indirectly upon the vegetable, and in 

 every country and in every clime does there not need to be this variety to meet 

 the varying wants of different animals? By it the savage, whether his home be 

 in a temperate or a torrid clime, finds all his wants of food and raiment and 

 shelter provided for. But indejiendent of its usefulness do Ave not find ample 

 reason for this variety in the beauty it adds to our earth? Is not this inter- 

 mingling and blending of the different forms and colors one of, if not the chief 

 ■element of beauty in tlie landscape? How is this variety produced ? A plant 

 is a liviiiff, slaiionari/ organism, which can only with the greatest difficulty be 

 moved from place to place. They cannot, lilce the clouds above us, be drifted 

 hither and thither by the winds, now forming in dense masses, and tlien blotted 

 •out of existence to be reformed in another place. Nor can they, like animals, 

 move singly or in vast herds from place to place at their own volition. And yet 

 grave and reasonable are the fears expressed that much of tlie good of our "Cen- 

 tennial" will be balanced by the introductioii through seeds in the packing of 

 foreign exhibits of pernicious weeds which in a few years will spread over the 

 whole country. How is it possible since plants are so stationary in their char- 

 acter that the descendants of plants growing tliis summer on the Centennial 

 packing grounds at Philadelphia can in a few years be found from Maine to 

 Oregon? The answer comes in\im\)t\j hi/ seeds. It is by seeds then that all 

 this mucli needed variety and intermingling of species is produced, and since it 

 is upon seeds, too, that tlie human race mainly depends for food, a little time 

 spent in the study of their structure and formation will be well spent. Botanists 

 tell us that a plant is made up of root, stem, und leaves, and that all its various 

 organs, no matter how diverse in form, texture, or color, may be referred to one 

 of these three elementary parts variously modified to meet the desired end; 

 that a potato is simply an enlarged and modified stem, a beet an enlarged 

 root, and the scales that enclose the buds of trees, or the different 

 parts of the most brilliant flowers are simply modified leaves. In the 

 language of Prof. Gray, then, we may say, "The Great Author of nature 

 nature having designed plants on one simple plan, just adapts that plan to all 

 cases. So when any special purpose is to be accomplished no new instruments 

 or organs are created, but one of the three general organs of the vegetable, root, 

 stem, or leaves is made to serve the purpose and is adapted to it by taking on 

 some peculiar form."' This Prof. Prentice of Cornell University used to call 

 the key-note of structural botany, and I must beg that you will keep it clearly 

 in mind, no matter how changed in shape, color, or texture, every part of the 

 plant may be referred to one of the three general organs, — root, steni or leaves. 

 Of these three organs it is the root, and the root only, that gives the 2:»lant its 

 stationary character; the leaves and branches can be moved as freely through 

 the air as any inorganic matter; but the home of the root is in the cool, damp 

 earth, from which it cannot be separated without tlie loss of a greater or less 

 proportion, and the injury of what we do secure. The root, then, seems to be 

 the insurmountable obstacle in the way of the easy distribution of plants. Is 

 it cm essential imrt of the 'plantl AVe answer, for its full growth and develop- 

 ment, yes ; upon it the jjlant depends for its food and drink, but it is not essen- 

 tial to life and some slight degree of growth, provided the nourishment and 

 moisture it should furnish is obtainable in some other way. The other parts 

 of the plant, the stem and leaves, take on a great variety of forms. One of the 



