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CHAPTER XV. 
OF FLOWERLESS PLANTS. 
Very little can be said to be positwely known of the manner 
in which the organs of flowerless plants perform what are 
supposed to be their functions. We are entirely ignorant of 
the manner in which the stems of those that are arborescent 
are developed, and of the course taken by their ascending and 
descending fluids, — if, indeed, in them there really exist 
currents similar to those of flowering plants ; which may be 
doubted. We know not in what way the fertilising principle 
is communicated to the sporules, or reproductive grains; the use 
of the different kinds of reproductive matter found in most 
tribes is entirely concealed from us ; it is even suspected that 
some of the simplest forms (of Algae and Fungi, at least) are 
the creatures of spontaneous growth ; and, in fine, we seem to 
have discovered little that is positive about the vital actions of 
these plants, except that they are reproduced by their sporules, 
which differ from seeds in germinating from any part of their 
surface, instead of from two invariable points. Under these 
circumstances, it would be useless to dwell upon the subject : 
those who wish to make themselves acquainted with the 
speculations of botanists, are referred to the valuable writings 
of Hedwig on Mosses, of Hooker on Jungermanniae, of 
Fries on Fungi, of Agardh, Greville, and Bory de St. Vin- 
cent upon Algae, of Meyer upon Lichens, of Bischoff* upon 
Equisetum, of Mirbel on Marchantia, of Martius and Mohl 
upon Ferns, &c. ; and, finally, to the introduction to the 
Natural system of Botany by the author of the present work. 
B B 
