CHAPTER II. 



CLASSIFICATION OF FERNS. 



HP' 



N order that we may better understand the 

 position occupied by the ferns in the clas- 

 sification of the vegetable kingdom, let 

 us examine the table which precedes this chapter, 

 and in which the groups, classes, and orders will 

 be found carried out in the several columns. The 

 arrangement is taken chiefly from Sachs' invalu- 

 able work, A Text-Book of Botany." The low- 

 est vegetable forms are at the bottom of the page ; 

 and, as we ascend, we reach the higher ones. The 

 column at the left contains the great groups, Pha- 

 nerogams, Vascular Cryptogams, 8zc. ; that is, the 

 plants contained in these groups have sufficient 

 differences to make it proper to arrange them in 

 this manner. For instance, we can say that all 

 Thallophytes possess characters which relate them 

 to each other ; while none of them have woody bun- 

 dles, a character which distinguishes Vascular Cryp- 

 togams from the groups below them, and is com- 



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