59 



Capsule opening by irregular transverse rents. 



Capsule globular, not pointed, sessile at the end of the stem. Spores 



large, few, many sided, smooth. ARCHIDIACE^:. 

 Capsule pointed. 



Capsule oval or oblong, with a long beak. New plants formed by 



offshoots springing from near the ends of the stems. 132 

 Capsule nearly globular. Plants very small, unbranched, annual. 



Calyptra, conical, bell-form, perfect. Leaves of loose texture 



throughout. PHYSCOMITRIOIDE.I:. 

 Calyptra hood-form. Leaves of closer texture, and greener at the 



apex than at the base. POTTIOIDK.K. 



132. Calyptra large, beaked, extending below the capsule, ragged at 

 base. Alpine or Arctic -plants, throwing out rootlets all along 

 the stem, forming branches and branchlets, and growing in dense 

 broad tufts. Leaves wide, concave, ribbed. VOITIACE/E. 

 Calyptra small, short. Leaves mostly narrow and composed of small, 

 green cells in the narrower part, and large, colorless cells in the 

 wider part. BKUCHIACE.E. 



133. Pedicels and capsules growing from the sides of the stem. 



Pleurocarps. 144 



Pedicels and capsules growing from the end of the stem or from the 

 ends of branches. Acrocarps. 



Cellular tissue in the stem composed of layers of three different 

 kinds. Capsule nearly globular. Lid hemispherical, not pointed, 

 very small. Calyptra small and disappearing early. Spores four 

 sided. Leaves very pale green, or colorless, not ribbed. Plants 

 growing in wet places. SPHAGNACE.E. 



Cellular tissue nearly homogeneous. Capsules mostly elongated, 

 having a pointed lid. Mouth of the capsule commonly fringed. 

 Spores spherical. 



Leaves with wings and a conspicuous vertical plate on the back, two 



ranked. 143 

 Leaves without a wide vertical plate on the back. 



