﻿Evans: The genus Plagiochasma 



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a single thallus. The appendages vary in form from narrowly 

 lanceolate to orbicular, when the genus as a whole is taken into 

 account, and they likewise vary markedly in size. As in other 

 genera of the Marchantiaceae the appendages are the first part of 



the scale to develop, covering over the embryonic region at the 

 growing point and being gradually pushed into a ventral position 

 by the apical elongation of the thallus. The basal portion and 

 the appendages are usually deeply pigmented with purple, but the 

 color of the appendages in particular often becomes bleached 



