Mosses and Lichens 



The spore-cases are solitary and terminal, immersed on a 

 short pedicel. They are almost spherical with a point on the 

 summit and a persistent columella. 



There are thirty-six species known in all, five in the United 

 States. 



The generic name Pleuridium is derived from the Greek 

 7r\vpiSiov, at the side. The name is suggestive of the position of 

 the spore-cases, which in some species appear to be on the sides 

 of the stems instead of on the summits, because a side branch has 

 grown from near the base of the spore-case but in the same 

 direction as the main stem leaving the spore-case behind. 

 Pleuridium subulatum, (Huds.), Rabenh. 



Habit and 'habitat. In loose bright-green and 

 silky tufts on earth and clay, along woods, banks 

 and heaths. 



Name. The specific name subulatum, from the 

 Latin subula, an awl, refers to the shape of the 

 upper leaves. 



Spores. 



Spore-case Veil. 



Leaves. with veiL 



P. subulatum. 



Plants (gametopbyte). Minute, ^ to -nrof an inch high, simple 

 or branching. 



Leaves. The lower distant, short, oval and taper-pointed; the 

 upper longer, more crowded, spreading; apex an awn minutely 

 toothed and rough on the back; vein broad, forming most of the 

 awn. 



Habit of flowering. Male and female flowers close together 

 on the same plant (paroicous) ; male flowers naked in the axils of 

 the leaves at the base of the spore-case. 



Veil (calyptra). Split on one side. 



Spore-case. Immersed in the leaves at the base, egg-shaped 

 with a tiny point at the apex (apiculate). 



Pedicel (seta). Short, immersed. 



Lid (operculum). None. 



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