62 DICRANACE/E. 



Tribe 2. Seligerieas. 



13. SELIGERIA B. & S. 



Minute, gregarious or caespitose plants, growing on rocks. 

 Leaves lanceolate or subulate, cells minute above, at basal angles 

 rarely coloured (not coloured in any of the British species). 

 Calyptra cucullate. Capsule smooth, symmetrical, or only very 

 slightly unequal, oval, with a distinct neck, peristome teeth 

 usually entire, rarely cleft, smooth, sometimes wanting. 

 Autoicous in all the British species. 



A genus of dwarf, almost microscopic plants, often growing 

 on the perpendicular sides of chalk-pits and cliffs, and some- 

 what difficult, on account of their minuteness and general 

 resemblance, to discriminate. Their presence is at times hardly 

 distinguishable except by the slight green or brownish tinge they 

 confer on the substratum of chalk or rock. 



{Peristome absent /. Doniana 

 Peristome present 2 



{Seta arcuate when moist 6. recurvata 

 Seta straight when moist 3 



{Capsule oval or oblong, contracted at mouth 4. paucifolia 

 Capsule short, wide-mouthed, turbinate when dry and empty 4 



{Perichstial Is. reaching base of capsule 3*. cuutifolia 

 Leaves not reaching base of capsule 5 



/ Ls. imbricated in three ranks ; cells long and narrow .3. tristicha 



5\Ls. not three-ranked ; cells shorter 6 



,/Ls. with short, wide, obtuse subula, entire .5. calcarea 



\Ls. longer, with narrow, acute subula, faintly denticulate 2. pusilla 



1. Seligeria Doniana C. M. (Gymnostomum Donianum Sm. ; 



Anodus Donianus B. & S., Schp. Syn. et plur. auct.) 



(Tab. XIII. D.). 



Very minute, gregarious, yellowish green ; stem very short, 

 simple. Leaves erect, straight, subulate from an ovate-lanceolate 

 denticulate base, channelled ; nerve reaching apex or slightly ex- 

 current, occupying the greater part of the minutely denticulate 

 subula; cells of base very thin, pellucid, rather incrassate, 

 rectangular and rhomboid, upper shorter, quadrate. Capsule on 

 a straight seta, minute, pale, hemispherical or turbinate after the 

 fall of the lid, thin-walled, gymnostomous ; lid obliquely conical. 

 Male infl. on a basal branch. 



Hab. Sandstone and limestone rocks. Not common. Fr. late summer. 



