PLAQIOTHECIUM. 211 



decumbentj branched. L. subcomplanate, sometimes 

 subsecundj ovate-lanceolate, shortly acuminatej entire, 

 obsoletely 2-nerved. Caps, cylindrical, curved, inclined 

 or horizontal, sulcate when dry, lid long, shortly 

 beaked. Dioicous. 



Roots of trees in woods, &c. September. 



Var. /3. succuLENTUM. Tbdmorden. 



513. P. undulatum, Linn. St. and br. procumbent, 

 2 inches or more. L. complanate, ovate, acute, not 

 acuminate, entire, undulate, margin incurved on one 

 side, faintly 2-nerved, whitish-green. Caps, cylindrical, 

 tapering at base, cernuous or horizontal, striate when 

 dry, lid with a short beak. Dioicous. 



Woods and moist places. September. 



2. Leaves spreading or spreading-secund. 



514. P. Miihlenbeckii, Schp. St. short, tufted, sub- 

 erect, with recurved, fasciculate branches. L. compla- 

 nate, subsecund, spreading, deltoid-ovate or subcordate, 

 tapering to a long, acuminate point, one side incurved, 

 dark green, finely serrulate, nerveless or shortly 

 2-nerved. Caps, oblong, cylindric, slightly inclined, 

 tapering below, striate when dry, lid short, conical. 

 Monoicous. July. 



Alpine rocks. Scotland, Ireland. 



515. P. Silesiacum, Seliger. St. and br. procumbent, 

 the latter arcuate. L. secund, mostly pointing upwards, 

 ovate-lanceolate, long tapering, concave, distinctly 

 serrulate, obsoletely and shortly 2-nerved. Caps, long, 

 subcylindrical, not striate when dry, curved, cernuous, 

 lid conical, pointed. Monoicous. 



Stems of decaying trees, rocks, &c. Summer. 



Kent, Yorkshire. 



p 2 



