SOLIDS AND FLUIDS OF VEGETABLES. 



In the greater number of vegetables, however, there is no- 

 germination until after the opening of the pericarp and the fall 

 of the seed. The time at which different species of seeds, af- 

 ter being committed to the earth, begin to vegetate, varies 

 from one day, to some years. The seeds of grasses, and the 

 grain like plants, as rye, wheat, corn, &c. germinate within two 

 days. The cruciform plants, such as radish, and mustard, the 

 leguminous, as the pea and bean, require a little more time. 

 The peach, walnut, and peony, remain in the earth a year be- 

 fore they vegetate. 



All kinds of plants germinate sooner if they are sown imme- 

 diately after being separated from their pericarps. 



Most vegetables preserve their vital principle for years : 

 some lose it as soon as they are detached from their pericarps. 

 This is said to be the case in the coffee and tea. The seeds of 

 some of the grasses, as wheat, &c. are said to retain their vital 

 principle even for centuries. It is asserted that mosses, kept 

 for near two hundred years in the herbariums of botanists, have 

 revived by being soaked in water. An American writer* says, 

 that seeds, if imbedded in stone or dry earth, and removed 

 from the influence of air or moisture, might be made to retain 

 their vegetative quality or principle of life for a thousand years." 

 But he very rationally adds, " life is a property which we do 

 not understand ; yet life, however feeble and obscure, is always 

 life, and between it and death there is a distance as great as 

 existence and nonexistence." 



The subjects upon which, in this lecture, we have been en- 

 gaged, properly come under the head of vegetable physiology, 

 a department of botany highly interesting, but too complicated 

 in its nature to be, except in a very limited degree, presented 

 to the mind of the youthful investigator. The physician finds 

 in the vegetable organization striking analogies to the internal 

 structure of the animal frame ; to him the language of physio- 

 logical botany is familiar, because it is borrowed from his own 

 science. On the other hand, the botanical student, in learning 

 the names and offices of the various internal organs of plants^ 

 is making no inconsiderable improvement in the knowledge of 

 the animal economy, and will feel his curiosity excited to search 

 into the mysterious organization of his own material frame. 



which had been kept in a warm cellar, I saW that they were swollen, and that 

 the out ward coat had burst; examining one seed, by removing the tegument and 

 separating the cotyledons, I saw by the help of a microscope the embryo, as if 

 in a germinating state : the radicle was like a little beak ; in the upper part or 

 plume was plainly to be seen the tuft of leaves and the stem. 

 * B. Barton. ' 



Time of germinating varies Vital principle of fruits Vegetable Physiology 

 Its language borrowed from animal physiology . 



