BY L. EODWAY. 205 



1913. 



Hypnum. Medium sized, decumbent, vaguely branched 



Leaves patent ; nerve lost above the middle. 

 Drepanocladus. Elongated water moss. Leaves very 



acute, the terminal ones secund, forming a sickle-like. 



end to the shoot ; nerve lost above the middle. 

 Campylium. Slender water moss. Leaves small, strongly 



divaricate; nerve lost in the apex. 

 Ptychomnion. Robust ground moss. Leaves strongly 



divaricate, nerveless. 

 Hypnodendron. Den.lroid. Leaves ovate, distichous; 



nerve lost in the apex. 

 Mniodendron. Dendroid. Leaves not distichous; nerve 



excurrent. 



Sub-familv.-Stereodonteae. Decumbput, vaguely or pin- 

 nately branched. Leaves smooth, shining, with a strong 

 tendency to become distichous or secund; nerves 2, very 

 short, obsolete or none. 



Bhaphidostegium. Leaves narrow, acute, nerveless, at 

 the basal angles three or four oblong inflated cells. 

 Lid with a long beak. 



Stereodon. Leaves generally secund, narrow acute, nerve- 

 less or veiy faint, an irregular patch of quadrate cells 

 at the angles. Lid conic. 



IsoPTERYGiUM. Leaves narrow, acute, sub-distichous, no 

 quadrate cells at the angles; no nerve. 



Plagiothecium. Leaves broarl, distichous, obliquely in- 

 serted, nerve double or forked. 



Catagonium. Leaves distichous, laterals conduplicate, 

 nerveless, apiculus short, recurved. 



AcANTHOCLADiUM. Lcavcs with a distichous teudeucv, 

 nerveless, oblong concave with a long slender api- 

 culus. 



AcROCLADiuM. Lcaves nearly orbicular, obtuse with one 

 or two short faint nerves. 



Sub-family.— Leskeae. Decumbent. Leaves small, cells 



rotundo-quadrate, papillose. 

 Thuidium. Branching pinnate; stems with paraphyllia. 

 PsEUDOLESKEA. Branches few irregular, stems without 



paraphyllia. 



Hypnum Dill. 

 Plants prostrate, creeping, seldom large or very small, 

 pinnately or vaguely branched. Leaves ovate to lanceo- 

 late; nerve single, lost above the middle; cells narrow. 



