Hairy-cap Mosses 



Slender Hairy-cap, Polytrichwm gracile, Dicks. 



Habit and bob itat. The slender Polytricbum is not common. 

 It may be found densely tufted on the ground in woods, or on 

 rocks. 



Name. The specific name gracile is from the Latin gracilis, 

 slender. 



Plant (gametopbyte) . Light green, erect, i to 4 inches high, 

 simple above, divided at the base and covered with soft matted hairs. 



Leaves. Spreading or erect when 

 dry, broadly lance-shaped ; apex sharply 

 taper-pointed ; base sheathing ; vein 

 broad ; margins serrate ; lamelJa 30 to 40, 

 not covering all of the leaf blade, 4 to 6 

 cells deep, the terminal cell elliptic in 

 section. 



Leaves at the base of the pedicel (peri- 

 cbcetial leaves}. Sheathing, | an inch long. 



Habit of flowering. Male and female 

 flowers on separate plants, (dioicous). 



Veil (calyptrd). Orange, not quite 

 covering the spore-case. 



Spore-case. --Erect or horizontal, 

 broadly egg-shaped; indistinctly six- 

 angled, mouth small; apopbysis obscure. 



Pedicel (seta). --Slender, orange, ito 

 2 inches long. 



Lid (operculuni). Conic, beaked. 



Teeth (peristome). With 64 teeth often confluent and unequal. 



Spores. Mature in summer. 



Perichaetial 

 leaf. 



Leaf. 



P. gracile. 



Portion of peristome. 



Spore-case with lid. 



P. gracile. 



Distribution. From the mountains of Virginia to Newfound- 

 land and west to the Rocky Mountains. Also in Europe, Asia 

 and the Pacific Isles. 



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