BY L. RODWAY. 9 



sections that are to be recognised more from general habit 

 than from consistent maintenance of the typical feature. 



Section 1, ACROCARPS.— The fruit is borne on the 

 end of the stem or branch. This may be obscured by a 

 later growth thrusting the fruit to one side, or even, in 

 some instances, mosses evidently having the closest affinity 

 to this group may have laterally placed fruits. 



Section 2, PLEURTCARPS — The fruit is normally 

 lateral. Only in one genus, Hedwigia, which has affinity 

 with both sections, is it apparently terminal. 



The other divisions do not require special description. 



The following rough guide may assist the student to 

 refer his plant to its proper family : — 



Div., ARTHRODONTEI. 



Sec. ACROCARPI. 



Fam. 1. TORTUL ACE AE.— Small, tufted. Leaves 

 broad, rarely narrow ; cells, small, round, or 

 quadrate. Calyptra nearly always cucullate. 

 Peristome single, when well-developed long 

 and twisted, each tooth split low down into 

 two slender legs ; often much reduced or ab- 

 sent. 



Fam. 2, DICRANACEAE.— Usually rather coarse. 

 Leaves long, pointed ; cells elongated, or in 

 some small genera short, seldom papillose, 

 Calyptra cucullate. Peristome single, teeth 

 split above. 



Fam. 3, GRIMMIACEAE.— Tufted or spreading. 

 Leaves small, tough, and rather narrow ; cells 

 small, incrassate. Calyptra, except in Zygo- 

 don, mitriform. Peristome single, or with 

 delicate liliform endostome processes ; some- 

 times longer or absent. 



Fam. 4, LEUCOBRYACEAE.— Leaves harsh, pale, 

 formed of two kinds of cells, large empty 

 ones, and intermediate narrow green ones. 

 Peristome as in Dicranum. 



