132 Plant Biology 



(2) Class Musci (True Mosses). — These are small, green plants 

 which are usually upright and may grow so densely in some moist places 

 as to form a mat of vegetation. Such masses of vegetation may consist 

 of hundreds of individual moss plants. Even though mosses contain 



A 



Sporophu'te 



f^hizo/a 



C 



eauee 



ler/d/a 



'di\ 



B 



Se-i 



Too't 



Elai 



er 



Jacket of capsule 



rlrchegonium 



Spore TnoTne'r cell 



D 



Fig. 44. — Leafy liverwort {Porella) of the phylum Bryophyta, class Hepaticae. 

 A, female plant with an attached sporophyte ; B, portion of a branch of a male 

 plant bearing antheridia which produce antherozoids (male) ; C, young arche- 

 gonium from an archegonial branch of a female plant showing an egg and elon- 

 gated neck; D, developing sporophyte (in longitudinal section) attached to the 

 parent gametophyte. 



