64 THE GENERAL MORPHOLOGY OF THE PLANT. 



CHAPTER II. 



OF THE GENERAL MORPHOLOGY OF THE PLANT. 



93. The Individual Plant, The organic elements, or cells in 

 their various forms, which have been treated of in the preceding 

 chapter, make up the individual plant. Looking now upon plants 

 as individual beings, we observe that they present themselves un- 

 der the greatest variety of forms ; some of them are of the utmost 

 simplicity, and many of these are so minute, that they are individ- 

 ually undistinguishable or invisible to the naked eye, and only be- 

 come conspicuous by their aggregation in great numbers : others 

 are highly complex in structure, and attain to a vast size, like the 

 giants of the forest, some of which have flourished for a thousand 

 years or more. All the larger vegetables are formed of a count- 

 less number of cells ; which, as they increase, arrange them- 

 selves so as to shape the fabric into definite parts, such as stem, 

 leaves, and roots, each having distinct offices to fulfil, while all are 

 subservient to the nutrition and perfection of the individual whole. 

 These parts are called the Organs of the plant ; or, more techni- 

 cally, the Compound Organs, since it is the cells of which they are 

 composed that are the real instruments, and carry on the opera- 

 tions of the vegetable economy. These organs are most distinct, 

 and at the same time most diversified, in the highest grade of 

 plants ; in the lower, they are successively less and less evolved, 

 until all such distinction of parts vanishes, and the plant is reduced 

 to a rounded or flattened mass of cells, to a row of cells strung end 

 to end, or even to a single cell. Since these last are the simplest 

 plants, and the higher acquire their more complex structure (as 

 will hereafter be shown) from an equally simple beginning, the 

 most natural order. for exhibiting the principal grades of vegeta- 

 tion is to commence with the lowest and simplest possible kinds, 

 namely, with 



94. Plants Of a Single Cell, There are several kinds of such 

 plants among the Algse (Sea-weeds, &c.), which rank as the low- 

 est order of the vegetable kingdom. They are especially interest- 

 ing here, because they furnish the readiest illustrations of the va- 

 rious methods of cell-formation which have been described in the 



