Mosses and Lichens 



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. 



Dry 

 spore -case. 



Plant (gametophyte). Very 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 (perichcetial 

 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. 



Spore-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 

 rii>id. They are repeatedly branched, commonly irregularly so, 

 \vith the branches more or less erect. 



292 



Spore-cases with 



peristome. 

 P. Muellerianum. 



