HORTICULTURAL JOURNAL. . 105 



among the living vegetables in the place which they ought to occupy among 

 the living beings. This is the end of Fossil botany. 



The different parts of the science which I have just enumerated constitute 

 Botany proper. Considered in its useful relation with man, applied Botany 

 comprehends Agriculture, Horticulture, Arboriculture, Medical and Indus- 

 trial Botany ; and I must; remark that it is owing to the discoveries of pure 

 science, that the old routines of cultivators have been enabled to be replaced 

 by more rational methods, raised upon the physiological observations of facts ; 

 at the same time, in industry, the exact determination of species can render 

 great service, in enabling us to avoid confusions and errors, as has been 

 proven in many examples, and as I have had occasion myself to show in the 

 employment of the fibres of two species of Phormium or Flax of New Zea- 

 land. 



If I did not fear becoming tedious, I would have selected in different bran- 

 ches of Botany, some facts recently brought to light and worthy of all your 

 attention, whether by the utility they present, or by the philosophical reflec- 

 tions to which they give place, and you would have perceived that all these 

 studies are equally prolific in interesting observations. I will confine myself 

 to citing one only of these facts, and I will select in precisely that part of 

 the science which at the first view seems the driest; I will not take for a 

 subject of study, one of those flowers attractive by their brilliant colours 

 their sweet perfumes, or the elegance of their forms; I will entertain you 

 with a vegetable production which is generally regarded with contempt, often 

 indeed with disgust — in a word, I will speak of that green slime which at- 

 taches itself to sunken wood, which floats on the surface of Stillwater, grows 

 at the bottom of streams or in the crevices of our maritime rocks ; and per- 

 haps you will be convinced that the study of an humble plant can serve as 

 the theme of the highest considerations of natural philosophy. 



Under the common name of slime, we are generally accustomed to desig- 

 nate and to confound a great number of plants of very different structures 

 but which all belong to the class called Al^se. Let us take a little tuft of a 



O CD 



certain species; we see at the first glance that it is composed of a compact 

 mass of threads very much bound together, of which each one constitutes a 

 complete plant. Let us submit one of these threads to the magnifying influ- 

 ence of a microscope ; we will see that it consists of a tube, hollow, trans- 

 parent and filled with a green matter to which the plant owes its colour. 

 "When it has arrived at that period of its life when, conformably to the gene- 

 ral laws of nature, it ought to reproduce and multiply itself, the green mat- 

 ter agglomerates in the interior of the tube, and there organizes itself under 

 U 



