— 274 — 



Perichetial leaves with excurrent costa. Annulus simple. — 

 Eur. r. France: Philibert; Goulard. 



* D.pallidisetns H. Mueller. — Trichostomum H. M.; Didy- 

 modon Kindb. 



Leaves plane below, the perichetial with percnrrent costa. 

 Capsule finall}' striate; annulus simple; pedicel wholly pale 

 yellow. — Eur. r. Germany: Geheeb. 



2. CrispuUformes. 



A. Leaves carinate from dilated undulate base gradually 

 subulate. Habit of Barhula (Tortella). R. fruiting. 

 S.D.oylindricns Bruch. — Weisia Bruch; Didymodon Br. eur. 



Leaves long narrow acute or subobtuse, sometimes sparingly 

 denticulate near apex; basal cells hyaline; costa not excurrent. 

 Capsule cyUndric. Tufts dark green. — Siliceous rocks. Eur. 

 not common. Switzerl.l Sweden: Lindberg. Amei\ Can.: Ma- 

 coun. 

 4.D.hil)eriiiciiS Mitten. — Tortula Mitt.; Didymodon Kindb. 



Differs from the last: Leaves entire acute more dilated at 

 base; basal cells abruptly passing to the rounded green ones. 

 Stem often very long. — Wet rocks r. Eur. Ireland: Stewart 

 and Holt. 



B. Leaves not carinate, sublinear or with sublinear or subu- 

 late acumen, entire. 



a. Leaves channelled or involute; basal cells us, yellowish, 

 upper very small opake papillose. 



S.D.brachydontins Bruch. — Trichostomum Bruch; Didymodon 

 Wilson; Trichostomum mutabile Notaris. 



Leaves sublinear or narrowly ovate-lanceolate gen. acute, 

 sometimes ovate-oblong short-acuminate, not channelled near 

 apex; basal cells brownish or yellowish; costa excurrent. Cap- 

 sule oval-oblong or subeylindric; teeth smooth us. short irre- 

 gular; pedicel yellow. Tufts loose 1 — 2 c. m. high or lower. 

 — " Calcareous rocks. — Eur. Switzerl.l Sweden: Zetterstedt; 

 P. Larsson. Belgium: Roemer. France: Philibert; Brebisson. 

 S.D.lutescens Lindberg. Mollia Lindb.; Didymodon Kindb. 



Differs from the last: Leaves smooth peUueid longer-apiculate; 

 upper cells better defined. Tufts yellowish green. Capsules 

 unknown. — Fissures of limestone rocks r. — Eur. »Irel.: 

 Lindb. »: Braithwaite. 

 T.D.crispuIus Bruch. ■ — Trichostomum Br.; Didymodon Wilson. 



Leaves from subovate base sublinear or r. suboblong, short- 

 attenuate often subobtuse, distinctly channelled or involute; 



