Thread-moss 



at the neck (collum) ; green with a bloom, becoming brown ; 

 somewhat round and wide-mouthed when empty. 



Pedicel. Long, generally reddish and bent at the base. 



Lid (operculum). Conical with a nipple (mammittaie) . 



Teeth (peristome). Large, orange-coloured. 



Annulus. None. 



Spores. Mature in spring and early summer. 



Distribution. Almost universal. 



Genus BRYUM, Dill. 



The plants of the Genus Bryum live on from year to year on 

 the ground or on rocks, seldom on trees. The stems are covered 

 with small red-brown filaments. 



The generic name is an ancient word for moss used both by 

 Gaius Plinius, "The Elder," a Roman naturalist, who perished in 

 the eruption that destroyed Pompeii, 

 and by Pedanius Dioscorides, a Greek 

 physician, who was the founder of 



Spore-case Spore-case 



with lid. without lid. 



B. roseum. 



B. argenteum. Portion 

 of peristome. 



B. argenteum. Leaf. 



botany and flourished in the first and second century. The name 

 Bryum was restricted to the present genus by Johann Dillenius, 

 a German, who was the first professor of botany at Oxford. 



The leaves are smooth with a solid round vein generally 

 extending beyond the apex; the cells are smooth, six-sided and 

 more or less elongated. 



The spore-cases are leathery, pear-shaped, narrowing down 

 to a solid neck (collum) with breathing pores (stomata) on the 

 surface; they are regular or rarely recurved. They have convex 

 lids with a tiny blunt point at the centre and are borne on long 

 and stout pedicels. 



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