The Sub-genus Plagiothecium 



Spores. Mature in autumn. 



Distribution. Vermont to Florida and Louisiana, west to 

 Missouri and Illinois. 



HYPNUM: Sub-genus PLAGIOTHECIUM, Schimp. 



The species of this genus are partly prostrate, irregularly 

 branching plants with rooting stems. They are soft and vari- 

 able in size. 



The leaves are thin, glossy and mostly entire ; a vein is 

 wanting or double ; very short and thin ; the 

 cells are long and narrowly rhomboidal- 

 hexagonal; larger at the base. 

 Male and female flowers are usually 

 found on the same plant. 



The veil is narrow and falls 

 early. The spore-case is somewhat 

 erect, oblique or almost horizontal, 

 oval-oblong to cylindri- 

 cal, somewhat arched, 

 short-necked, thin, 

 smooth or rarely wrin- 

 kled when dry. 



The teeth are whitish. 

 The name is derived 



from the Greek TrXayio?, oblique, and dqictov, a little 

 chest, referring to the spore-case. 



Plagiothecium Muel- 

 lerianum, Schimp. 



Habit and habitat. 

 This moss is found in rocky 

 ravines ; it grows in loose, 

 bright and shining green 

 tufts. 



Name. The specific 

 name, Muellerianum, 

 was given by William 

 Schimper in honour of 

 Baron Ferdinand Mueller, 

 Government botanist of 

 Australia. 



Stem-leaves. 



Cells. 



P. Muellerianum. 



Spore-case 

 with lid. 



Leaves at base of pedicel. 

 P. Muellerianum. 



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