434 



LEUCOBRYACEAE. 



Family 2. LEUCOBRYACEAE C. Muell. 



White Moss Family. 



Plants perennial, growing in dense pale green cushions ; stems medium 

 to large, branching; leaves crowded, sometimes fragile and breaking off, 

 vein broad filling most of the leaf, blade very narrow, the green cells of 

 the leaf small, in a single central band between several layers of larger 

 hyaline cells. Pedicels erect, terminal; capsule erect or horizontal, regular 

 or irregular ; peristome single, teeth 8 or 16 ; lid beaked ; calyptra cucullate. 

 Nine genera and 229 species are known. 



1. LEUCOBRYUM Hampe. 



Characters of the family. A genus of 121 species, widely distributed in 

 temperate and tropical regions. [Greek, in reference to the pale color of the 

 plants.] The following species typical. 



1. Leucobryum glaucum 

 (L.) Sehimp. White Moss. 

 (Fig. 473.) Plants in com- 

 pact, pale green cushions ; stems 

 branching, seldom more than 2 

 inches high; leaves crowded, 

 erect-spreading, sometimes 

 curved; base ovate, narrowed to 

 a tubular point, apex acute, 

 minutely denticulate, hyaline 

 blade of the lower part of the 

 leaf about 5 cells wide on either 

 side of the broad vein; pedicel 

 dark red; capsule nodding, 

 strongly curved and furrowed 

 when dry; annulus none; peri- 

 stome single, teeth 16, papillose, 

 _L "^^^d^ divided to below the middle ; lid 



I ^^^ft vV beaked; spores slightly rough. 



On the ground among ferns 

 and palmettos in marshes. New- 

 foundland to Minnesota, south to 

 Florida and Louisiana ; also 

 throughout Europe. [Bryum glau- 

 cum L.] 



Family 3. FISSIDENTACEAE Bruch & Sehimp. 



FissiDENS Family. 



Small plants, usually growing in moist shady places, on earth or 

 stones; stems erect or decumbent, simple or sparingly branched; leaves 

 few, always two-ranked and conduplicate, clasping at base, with a single 

 vein and with an apical and dorsal prolongation especially in the upper 

 leaves. Pedicels terminal or on lateral buds; capsules ovoid or eylindric, 



