FLORA OF TUE MOUNTAIN. 257 



Order IIepatice, (Liverworts.) 



This order of cryptogaraic plants has many repre- 

 sentatives on the Alleghany Mountain. They arc small 

 cellular plants, some of them resembling mosses, and pre- 

 senting many ])oints of similarity, in form and habits, with 

 that order. Tiiey arc diversified in their forms of vegeta- 

 tion and reproduction, the quaint and peculiar style of which 

 is striking, even to the ordinary observer, and possesses 

 marked attractions for the botanist. In Gray's Manual, 

 William S. Sullivant has reported 38 genera, and 108 spe- 

 cies. For the clever monograi)h, with beautifully elaborated 

 figures of the genera of this order, by this distinguished 

 cryptogamist, the student of American botany must feel 

 under perpetual obligation. A heretofore comparatively 

 closed book is now unsealed, and the student can walk with 

 open eyes into a new and enchanting region. The Alle- 

 ghany, as already remarked, is a rich Hepatic field, and will 

 give an abundant harvest to the laborer in this department. 



THALLOPHYTES. 



Order Liciienes, (Lichens.) 

 The class of organic forms called Tiiallodhytes, are the 

 simplest vegetable structures. They have no distinction into 

 stems, roots, or leaves, as the higher cryptogamic ])lants ex- 

 hibit, but are composed of a mass of cells accumulated in a 

 parenchymous plane, called a TJiallus or Frond. The order 

 Lichenes is in this group. They are peculiar, both as to 

 their nutrition and reproduction, and show a strong bearing 

 toward that troublesome region of speculation in which com- 

 mence the great (juestions of umvocal and equivocal gene- 

 ration. On SPONTANEOUS generation, or " matter assuming 

 organization under the influence of water and light," the 

 following observations of Lindley may seem to savor of an 

 unorthodox philosophy to many who are given to intellectual 



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