PHYTOLOGY. 289 



differences are only conceivable through the presence of 

 different organs. 



1 543. Species is in the animal kingdom that which copu- 

 lates without necessity and compulsion. The same defi- 

 nition is applicable to plants. The species range, without 

 doubt, according to the diversities in the individual organs 

 themselves, which admit of a great multitude of combi- 

 nations, the number of which is not as yet to be deter- 

 mined. 



1544. The component parts of the fungi are either 

 perfectly indifferent, mucous or gelatinoid matter; or 

 they are of an alcaline nature, being acrid, poisonous, and 

 such like. Their odour is usually dead, disagreeable, and 

 loathsome, or analogous to their essential process of de- 

 composition. 



CLASS II. 



Vessel- or Duct-plants Mosses. 



1545. The intercellular passages or succigerent vessels 

 of plants make their first appearance in a state of perfec- 

 tion, when, the cells being extended lengthways, have 

 become hexagonal and are placed in regular juxtaposi- 

 tion. In these plants therefore we meet with regular 

 cellular tissue, but still without spiral vessels or tracheae. 



1546. As the vessels or ducts constitute the funda- 

 mental tissue of the liber, while this is the principal sys- 

 tem of the stalk ; so now does the stem begin to be 

 manifested and separated from the fruit. The seeds 

 are no longer therefore distributed in the present class 

 throughout the whole trunk, but developed in a special 

 involucrum or theca, which corresponds to the puff-ball, 

 or to the pileus of the higher organized fungi. 



1547. Plants with vessels, and consequently a cauli- 

 form formation, have at once also the commencement of 

 a bark, and next the green colour. The vascular are the 

 first green plants, and differ chiefly through that character 

 from the fungi. They are the Fiicaca or Sea-wracks. 



1548. They have the colour of the water, because the 



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