LIVERWORTS 



305 



worts make up a class of low, flowerless plants standing above the 

 algae and fungi. They all possess chlorophyll. In many of 

 them the plant body is flattened and leaf -like, more or less rounded 

 in some, or strap-shaped in others, and lobed or forked in various 

 ways. These lobed forms suggested the name liverwort which 

 has been adopted as the name of the class, with the technical 

 name, Class Hepatica. This plant body is a thallus, a word 

 applied to those low plant forms which are not divided into a 

 true stem, leaf and root.* They are attached to the ground, to 



Fig. 279. 



Section of thallus of Marchantia. A, through the middle portion; B, through the marginal 

 portion; p, colorless layer; chl, chlorophyll layer; sp, stomate; h, rhizoids; b, leaf-like outgrowths 

 on under side (Goebel). 



tree trunks, or rocks by slender thread-like outgrowths called 

 rhizoids, through which much of the water and mineral foods are 

 absorbed. Nearly all of the liverworts grow in damp situations, 

 or float on the water. The male and female organs are a sperm 

 case (antheridium) with motile sperms, and an egg case (arche- 

 gonium) with an egg. The egg case of the liverworts is a more 



* The word thallophyte, however, technically applies only to the algae 

 and fungi, which are the thallus plants par excellence. 



