
 
        
         
		6.  P. commune, Linn.  Plants very  large, loosely cespitose,  
 dark  red:  leaves  open,  recurved,  very  long-sheathing,  membranaceous, 
   whitish  at  base;  borders  narrow,  sharply  and  
 densely  serrate  to  the  enlarged  base;  borders  of  the  lamellæ  
 papillose ;  perichætial  leaves  erect, very long-sheathing,  awned:  
 calyptra  very  hairy,  descending  below  the  capsule:  capsule  
 sharply  angled,  long-pedicellate,  light  brown,  horizontal  when  
 di-y  and  empty ;  lid  flattened-convex  at  base,  conical-apiculate,  
 with  red borders. — Spec. PI.  1109;  Bryol.  Eur.  t. 425. 
 Var. perigonia le , Bruch & Schimp.  Smaller,  often  bifid:  
 perichætial  leaves  all  membranaceous,  long-aristate :  lid  pale,  
 short-apiculate. — P. perigoniale, Michx.  FL Bor.-Am.  ii.  293. 
 Hab.  Bogs and woods ;  plains and mountains.  June.  Very variable. 
 T kibb  XV.  BUXBAUMIEÆ. 
 Small  stemless plants, with  large oblique  ventricose  capsules,  
 sessile or with  short  thick  pedicels.  Calyptra very small,  conical, 
   smooth.  Sporangium  pedicellate,  small,  attached  by  
 filaments  to  the  walls  of  the  capsule.  Peristome  double,  the  
 outer  rudimentary,  or  composed  of  one or  more rows of  more  
 or  less  perfect  teeth,  the  inner  membranaceous,  and  forming  
 a truncate  cone of 16 or 82  twisted folds.  Spores very small. ° 
 9 8 .  DIPHYSCIUM,  Mohr.  (PI.  3.) 
 Stems very short, simple, with numerous long radicles.  Stem-  
 leaves lingulate,  thick,  composed  of  a  double  stratum  of  cells,  
 costate, chlorophyllose ;  areolation very small, round-hexagonal ;  
 perichætial  leaves  larger,  ovate-lanceolate,  thin,  snbmembrana-  
 ceous, deejily serrate  or  lacerate-ciliate  at  the  apex;  costa  ex-  
 current  into  an  awn.  Flowers  dioeoious ;  the  male  open,  on  
 j)lants similar to the fertile  ones, the paraphyses longer than the  
 antheridia ;  the female gemmiforrn, with paraphyses shorter than  
 the  long-styled  archegonia.  Vaginule  formed of  the thickened  
 upper  part  of  the  stem,  bearing  the  perichætium.  Calyptra  
 acute-comcal,  covering  the  lid.  Capsule  ventricose,  ovate-  
 conical,  yellowish green.  Lid  conical,  acute.  Outer peristome 
 formed  on  an  annulus with  sixteen  notches  representing  teeth  
 more or  less distinctly. 
 1.  D.  fo lio sum ,  Mohr.  Widely  cespitose,  dark  green:  
 stem-leaves  crenulate  on  the  borders  by prominent  cells, crispate  
 when dry :  capsule immersed in  the  colorless perichætium ;  
 teeth  of  the  outer  peristome  very short,  triangular, granulose,  
 transversely  articulate,  often  perforated  in  the  middle,  pale  
 yellow,  purple  at  the  apex. — Obs. Bot.  34 ;  Bryol. Eur.  t. 428  
 and  428'’-  Puxhaiimia foliosa, Web.  FL  Gott.  128.  Webera  
 sessilis, Lindb.  Ofv. Vet. Akad.  Forh.  xxi.  576. 
 Ha b .  Clayey and  shady  sandy banks,  along roads. 
 99.  BUXBAUMIA,  Hall.  (PL 3.) 
 Plants  very  small,  gregarious,  growing  on  soil  or  decaying  
 wood.  Lower  leaves  broadly  ovate  or  ovate-lanceolate,  tho  
 upper  ovate  and  linear-oblong, without  costa,  coarsely dentate-  
 ciliate  on  the  borders  by  prominent  cells ;  areolation  loose,  
 oblong-hexagonal,  not  chlorophyllose,  pale  near  the  base,  reddish  
 or orange-colored toward the  apex,  irregular when  young ;  
 basilar  cells  transformed  into  laciniæ  or long brown filaments,  
 becoming roots and covering the  stem and vaginule with a very  
 thick tomentum.  Flowers dioecious ;  male plants  smaller  than  
 the  fertile,  with  a  few  thin  leaves  not  laciniate  when  old ;  
 antheridia solitary or in pairs, with few paraphyses ;  perigynium  
 of  the  fertile  flowers  ovate-oblong,  of 9 to  12  leaves, becoming  
 lacerate  after  fecundation ;  archegonia  1  to  3, with  few  short  
 paraphyses ;  perichætial  leaves  very  irregular,  ramose-ciliate  
 after  fecundation.  Vaginule  thick,  fleshy,  formed  of  the  perichætial  
 part of the stem.  Calyptra  conical,  cylindrical,  obtuse,  
 covering  the  lid  only,  detached  before  the  maturity  of  the  
 fruit,  sometimes slightly split on  one  side.  Capsule  on  a  thick  
 red  densely  verrucose  pedicel,  oblique  on  a  solid  erect  neck,  
 ovate  or  ovate-oblong,  ventricose,  flattened  on  one  side.  Lid  
 conical-cylindrie,  obtuse.  Peristome  double,  the  outer  either  
 imperfect  and  adherent  to the  annulus,  or perfect,  formed of a  
 double or triple series of teeth, the inner like that of Diphyscium.