HEPATIC^. 281 



almost without sinuosities^ wlien it has the appearance of 

 some flattened Cactus on a small scale. These frondose 

 stems are horizontal, and attenuated towards tlie edges. In 

 the foliose species of Jioigennannia, the stems form com- 

 pact cushions, and in this state may readily be taken for 

 true Mosses. The ramifications of various species are very 

 elegant, as those can testify who have gathered in this or 

 other lands the beautiful Jmigermannia tomentella, or its 

 allies. In secluded spots it forms 



"An emerald spot 

 Romantic and most beautiful, 

 Where print of human foot is not : 

 Meet haunt for fairy bright or fay." 



The forms and divisions of the stem and branches afford 

 valuable characters for distinguishing species. 



Leaves. — Sir J. E. Smith, and other authors who have 

 followed him, have regarded not only the lichen-like 

 branches of Marchantia, but most of the leafy expansions of 

 Jimgermannla, as modifications of fronds, and consequently 

 consider this as a leading characteristic of the family. Ne- 

 vertheless, with an eminent author, whose opinion we quote, 

 we consider these expansions of eel hilar tissue equally en- 

 titled to the appellation of leaves as these organs in the true 



