21 



crisped when dry; cells mostly round-oval, less often sub- 

 oblong, seldom narrower. Paraphyllia sometimes wanting. 



Fam. 13. Hypnacese. 



A. Capsule generally symmetric and erect, not 

 curved. 



I. Pylaisiece. Leaves neither distichous nor falcate ; 

 angular or alar cells subquadrate ; costa short and double 

 or indistinct. Endostomial segments sometimes partly con- 

 nate with the teeth; annulus mostly indistinct. Pedicel 

 of the capsule smooth. Monoecious. 



46. Pylaisia. Endostomial segments reaching above 

 the teeth. Lid of the capsule not rostrate. Alar (angular) 

 leaf-cells small, usually green. 



47. Pylaisiella (new genus). Endostomial segments 

 lower than the teeth. Lid of the capsule rostrate. Spe- 

 cial alar cells sometimes large and pellucid. 



B. Capsule generally asymmetric and inclined or 

 curved. 



IL Raphidostegiece. Leaves not rarely subdisti- 

 chous, often incurved or subfalcate, acute, generally acu- 

 minate, mostly recurved at the borders; alar cells vesiculi- 

 form and rotundate, orange or hyaline; inner cells generally 

 narrow. Capsule usually small ; lid rostrate ; pedicel smooth. 



48. Raphidostegium. Leaves usually small; costa 

 mostly indistinct. Stem without paraphyllia. 



III. PlagiotheciecB. Leaves generally distichous or 

 slibdistichous by the complanate branches, not curved, 

 seldom recurved at the borders; alar cells polygonal or 

 indistinct; inner cells generally narrow. Lid of the cap- 

 sule sometimes rostrate; pedicel usually smooth. Stem 

 sometimes (in some species of Rhynchostegium] with 

 paraphyllia. 



a. Leaves mamillose above. 



49. Rhynchostegium. Leaves acuminate and acute; 

 cells not seriate; costa often simple. Lid of the capsule 

 usually rostrate. Stem often with paraphyllia. 



