OF FOUEST-TREES. 



33 



not, as we affirmed, operate to the full extent and perfection of what it cHAP. 

 gives and contributes of necessary and constituent matter, without the 

 soil and temper of the climate co-operate, which otherwise retards 



Vegetables being fixed to a place, have few offices to perform. An increase of body 

 and maturation of their seed, seems all that is required of them. For these purposes. 

 Providence has wisely bestowed upon them organs of a wonderful mechanism. The 

 anatomical investigation of these organs, is the only rational method of arriving at any 

 certainty concerning the laws of the vegetable economy. Upon this subject Dr. Hales 

 judiciously observes, " That as the growth and preservation of vegetable life is promoted 



and maintained, as in animals, by the very plentiful and regular motion of their fluids, 

 " which are the vehicles ordained by Nature to carry nutriment to every part, it is, 

 " therefore, reasonable to hope, that in them also, by the same method of inquiry, con- 

 " siderable discoveries may in time be made ; there being, in many respects, a great 

 ''analogy between plants and animals." 



The seed of a plant, after it has dropt from the ovarium, may be considered as an 

 impregnated ovum, within which the embryo plant is securely lodged. In a few days 

 after it has been committed to the earth, we may discern the rudiments of the future 

 plant. Every part appears to exist in miniature. The nutritive juices of the soil insinuate 

 themselves between the original particles of the plant, and -bring about an extension 

 of its parts. This is what is called the growth of the vegetable body. With regard to 

 this increase by addition and extension, there seems to be a great analogy between the 

 animal and vegetable kingdoms. I have already endeavoured to prove, that oily 

 particles constitute the chief nourishment of plants and animals ; and as I apprehend that 

 much depends upon a proper investigation of the subject, I shall occasionally introduce 

 some other proofs in support of my opinion. Every one knows that animals, instead of 

 being strengthened, are enfeebled by a supply of improper nourishment. It is the same 

 thing with regard to vegetables ; but with this difference, that animals refuse whatever is 

 improper, while vegetables, from their passive nature, must be content with what we 

 give them. The impregnated ovum of every animal, after it has passed down the 

 Fallopian tube, and fixed itself to the bottom, or side, of the uterus, is found to contain 

 the tender embryo within two membranes called Chorion and Amnion. In this situation 

 the embryo could not long subsist without a supply of nourishment* Nature has therefore 

 bestowed upon it a placenta and umbilical chord, through which the blood and juices of 

 the mother are transmitted, for its preservation and increase. Seeds are disposed by 

 Providence nearly in the same manner. They have two coverings, answering to the 

 Chorion and Amnion, and two lobes which perform the office of the placenta. These 

 lobes constitute the body of the seed, and, in the farinaceous kinds, they are the flour of 

 the grain. Innumerable small vessels run through the substance of the lobes, which, 

 uniting as they approach the seminal plant, form a small chord to be inserted into the 

 body of the germ. Through it the nutriment supplied by the placenta, or lobes, is 

 conveyed for the preservation and increase of the embryo plant. In order that I may be 

 Volume I. , M 



