Liverworts or Hepatics 



LEAFY HEPATICS, SCALE MOSSES, OR FOLIOSE HEPATICS 



Porella platyphylla (See Colour Plate XIV), is a good ex- 

 ample of the foliose or leafy hepatics and from a study of it 

 one may become familiar with the conspicuous parts of this class 

 of mosses. 



Margins irregular. 



Margin inrolled. 

 Leafy hepatics. 



Margin toothed. 



The plants grow flat upon the bark of living trees. Each 

 plant consists of a creeping stem, with side branches which may 

 in turn bear branches. 



The principal leaves are set at right angles to the stem and 

 their sides overlap so as to conceal the stems. 



They are two-lobed with one lobe above the stem and one 

 below. 



A third row of leaves grows on the underside of the stem. 



Two leaves showing lobe 

 and lobule. 



Creeping stem and branch. 



Under view of stem showing 

 third row of leaves. 



Porella plalyphylla. 



In some leafy hepatics, the tips of the leaves overlap the base 

 of the leaf in front; in others the tips of the leaves are under- 

 neath the bases of the leaves in front. 



The margins of the leaves of different species vary, they are 

 recurved, toothed, fringed, inrolled, or entire. 



The apex may be blunt or pointed or of many other designs. 



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