22 



50. Taxithelium. Leaves obtusate or short-acumi- 

 nate; cells seriate; costa indistinct. Lid of the capsule 

 not rostrate. Stem without paraph^ilia. 



b. Leaves not mamillose. Stem without paraphyllia. 



51. Plagiothecium. Lid of the capsule usually not 

 rostrate. Alar leaf-cells not numerous, often indistinct; 

 apical cells narrow; costa mostly indistinct or short and 

 double. 



52. Stereophyllum. Lid of the capsule rostellate. 

 Alar leaf-cells small but very numerous; upper cells sub- 

 oval; costa long and simple. 



IV. Amblystegieoe. Leaves neither distichous nor 

 falcate, rarely recurved at the borders; alar cells polygonal 

 or indistinct; middle cells generally oval-oblong. Lid of 

 the capsule not rostrate; pedicel sinooth. Stem without 

 paraphyllia. — Tufts usually not shining. Leaves mostly 

 small. 



53. Amblystegium. Leaves not limbate, all acu- 

 minate and acute; costa often short and double (or indi- 

 stinct). 



54. Platyloma (new genus). Leaves broadly lim- 

 bate by linear cells, those of the branches obtusate; costa 

 long and simple. 



V. Hypnece. Leaves generally not distichous, often 

 falcate; alar cells polygonal or indistinct; upper and middle 

 cells generally narrow. Lid of the capsule often rostrate ; 

 pedicel often rough. Stem less often with paraphyllia. 



Here belonging genera are rather subgenera of Hyp- 

 num. and not wholly distinct. 



a. Leaves generally obtusate (at least those of the 

 stem), not triangular; costa often short and double. Lid 

 of the capsule not rostrate; pedicel smooth. Stem without 

 paraphyllia. 



55. Calliergon (new genus). Leaves of the bran- 

 ches sometimes falcate. 



b. Leaves acuminate and acute, generally triangular, 

 not falcate; costa long and simple. Lid of the capsule 



