The Grimmia Mosses 



The generic name was given in honour of J. F. C. Grimm, a 

 German botanist, who was a physician of Gotha. 



The spore-cases are oval and smooth, borne on arched or 

 straight pedicels. The peristome consists of sixteen red, lance- 

 shaped teeth, entire or cleft at the apex and often perforated below. 

 There are about two hundred and forty species known at 

 present, fifteen of them in North America. 

 Grimmia apocarpa, Hedw. 



Habit and habitat. Loosely tufted to form olive-green or 

 black tufts on rocks or stone walls or even on roofs. There are 

 varieties which grow in streams. 



Name. The specific name apocarpa from euro, without and 

 KapTros, a fruit, was given by J. G. Hedwig, in 1787, to describe 

 the hidden spore-case. 



Plant (gametophyte) . Robust, the stems one inch 

 long, branching in pairs, free from root-like fibres. 



Leaves. Lance-shaped, open when moist, erect 

 when dry; apex sometimes slightly toothed, the upper 

 leaves usually prolonged into a short, rough hair about 

 one-quarter as long as the leaf; the base is concave, 

 G. apocarpa, becoming keeled upward; margin recurved; the vein 

 Tmmlred continued into the transparent hair, or vanishing below 

 spore-case. th e apex ; cells, the basal rectangular, then narrow, the 



upper rounded. 



Leaves at the base of the pedicel (pericbatial leaves). 

 Broader, thinner; vein narrow; apex with or without short 



point. 



Habit of flowering. Male and female flowers on separate part 

 of the same plant (autoicous); male flower-clusters bud-like. 



Veil (calypird). Very small, not reaching 

 below the lid, lobed at the base. 



Spore-case. Egg-shaped, almost concealed 

 in the leaves at the base, red. 

 Pedicel. Very short. 



G apocarpa. ^ (ofierculum) .Bright-red, tipped With G. apocarpa. 



Spore -case ' Spore -case 



with lid. a sharp point; columella attached to the lid W ithveii. 

 and falling with it. 



Annulus. None. 



Teeth (pensiome). Arising below the mouth, large, purple- 

 red, entire or perforated, spreading when dry. 



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