Mosses and Lichens 



sometimes a long one. The peristome may have imperfect 

 teeth or none or sixteen tiny flat ones. 



There are about eighty-three species in all, fourteen in North 

 America. 



The genus was named for Professor D. F. Pott, 

 a German botanist. 



Pottia truncata, Fuern., I. c. 

 Habit and habitat. Common in loose bright-green 

 tufts in fields and gardens and along hedge-rows. 

 Name. The specific name is the Latin truncata, 

 cut off squarely, and refers to the abrupt 

 summit of the spore-case which appears as 

 if it had been sliced off. 



Plant (gametophyie). Small, \ of an inch 

 high and simple, or longer and branching. 



Leaves. Long-oval with the narrow end 

 attached to the stem, concave, smooth ; 

 apex taper-pointed, tipped with a sharp 

 point ; margin flat ; vein extending below 

 or beyond the apex. 



Habit of flowering. Male and female flowers on the same 

 plant (monoicous). 



Veil (calyptra). Split on one side, smooth. 

 Spore-case. Egg-shaped, broad end up (truncate). 

 Pedicel. Short, red. 



P. imncnta. 



Spore-cases with 

 veils. 



Veil. 



Spore-cases. 

 P. truncata. 



Lid with 

 columella. 



Sporc-cacc 

 with Sifted 

 lid. 



Lid (operculurti) . Plano-convex with an oblique beak, falling 

 with the columella attached. 

 Teeth (peristome). None. 

 Spores. Brown, mature in fall and winter. 

 Distribution. North America, Europe, Asia. 



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