Portion of peris- 

 tome showing one 

 outer tooth on the 

 right with annulus 

 cells at its base, one 

 keeled inner tooth 

 and two cilia on the 

 left. 



Mosses and Lichens 



Plant (gametophyte).--Vexy small; stems with runners, 

 creeping, with branches erect, rooting at the base and some- 

 times at the apex. 



Leaves. In two rows, spreading, concave, 

 ovate-lance-shaped at the base, taper-pointed, 

 with an abrupt, short, acute point ; margin 

 entire ; 'vein wanting ; base not growing down 

 the stem ; cells narrow, uniform. 



Leaves at the base of the pedicel (perich&tial 

 leaves). Half-clasping at the base, oblong-ovate, 

 taper-pointed, entire. 



Habit of flowering. 

 Male and female 

 flowers on separate 

 plants (dioicous). 



Veil (calyptra). 

 Small. 



Sp ore- case. 

 Somewhat nodding, 

 tapering from the en- 

 larged mouth toward 

 the pedicel, long- 

 necked, enlarged at the mouth and bell-shaped when dry. 

 Pedicel (seta). Short, purple. 

 Lid (operculum). Conical, short-beaked. 

 Teeth (peristome). Distantly jointed, cilia short, robust, 

 unequal. 



Annulus. Narrow, simple. 



Spores. The fruit is very rare. 



Distribution. Found in Europe and eastern North America. 



HYPNUM: Sub-genus AMBLYSTEGIUM 



The species of the Sub-genus Amblystegium vary in size 

 from minute to large and robust and vary in colour from bright 

 yellow-green to dark dull-green. The stems are prostrate, creep- 

 ing, decumbent, ascending, or erect. The male and female 

 flowers are usually on separate plants. 



The stems are usually tender and soft, but are occasionally 

 rigid. They are repeatedly branched, commonly irregularly so. 

 with the branches more or less erect. 



Spore-cases with 

 peristome. 



P. Muellerianum. 



Dry 

 spore -case. 



292 



