Mosses and Lichens 



plants have of twisting and untwisting their pedicels as they 

 are alternately moistened or dried. 



Plant (gametophyte). The young plants 

 are found in the fall. They are yellow-green 

 with simple or branching stems, living but 

 one year, or continuing by new growths. 



Leaves. Variable; tufted at the apex of the 

 stem, usually erect and pressed together; ob- 

 long egg-shaped; apex short-pointed; margin 

 entire; vein reaching the apex. 



Habit of flowering. Male and female flow- 

 ers on the same plant (mono icons) ; terminal; 

 the male on primary stems, the female on sec- 

 ondary. 



F. hygrometrica. Leaf. 



L pyriforme. 

 (See page 217 ) 



F. hygrometrica. Cross section of young 

 pedicel. 



Veil (calyptra). Conical, shining, inflated at the base, split 

 up one side, composed of bladder-like cells. 



Spore-case. When immature, erect, nearly symmetrical; 

 when mature, pear-shaped, with the small end narrowed to an 

 elongated and curved neck (collum). One side is more swollen 

 than the other (gibbous) ; leathery, reddish, and deeply furrowed 

 when old. 



Spore-sac. Much smaller than the spore-case, attached to it 

 by loosely tangled threads. 



Pedicel (seta). Straight or arched above, 

 i to z\ inches high, twisting and untwisting 

 with the changes in the humidity of the air. 



Lid (operculum). Small like a flat saucer. F. hygrometrica. 



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