100 BRYACE^. [Pharomitrium. 



Tribe III. POTTIEJE. 



Plants generally perennial ; innovations f astigiate ; areolation 

 parenchymatous, quadrate-hexagonal in the upper part, more or 

 less papillose, very chlorophyllose, dilated and hyaline toward 

 the base. Calyptra cucullate, rarely mitriform-lobate, smooth. 

 Capsule generally erect, symmetrical. Peristome simple, rarely 

 absent, of 16 teeth, either rudimentary, flat and membranaceous, 

 or more generally perfect, often split to the base into 32 round 

 filiform indistinctly articulate segments. 



38. PHAROMITRIUM, Schimp. 

 Capsule immersed, globose, without peristome, enlarged at 

 the orifice after the falling of the lid, soft, loosely areolate. 

 Calyptra oblique, plurilobate. 



1. P. subsessile, Schimp. Plants short, cespitose : leaves 

 obovate-oblong, acuminate, with a round costa passing up into a 

 long pellucid hair-point, bearing in the middle two to four 

 follicles filled with a granulose mucilaginous mass, often divided 

 into two to four lamellse : flowers monoecious ; anthers para^ 

 physate in the axils of a single perigonial leaf near the base of 

 the perichaetium : capsule on a short erect pedicel ; lid large, 

 plano-convex at base, abruptly narrowed into a short slender 

 and erect or inclined beak; annulus none. — Syn. Muse. 121. 

 SchisticUiim subsessile, Brid. Pottia subsessilis, Bruch & 

 Schimp., Bryol. Eur. t. 117. 



Hab. On sandy or clayey ground, stone walls, etc. ; plains and moun- 

 tains; not rare. 



Variable in size, from one or two m.m. to four cm. or more in length; 

 borders of the leaves generally entire near the apex, sometimes with a 

 few distinct teeth. Pharomitrium exiguwn, Austin (Bull. Torr. Club, 

 vi. 42), mere buds or young plants with scarcely any stems, and with the 

 borders of the leaves denticulate at the apex, is a variety which is found 

 also among European specimens. 



39. POTTIA, Ehrh. (PI. 2.) 

 Sparingly branching from the base or simple. Leaves ovate- 

 oblong, acuminate, soft, opaque, smooth or papillose ; costa 



