50 BUXBAUMIACEjE. 



8. DIPHYSCIUM Mohr. 



Plants very short, gregarious. Leaves Ungulate or lanceo- 

 late, fragile, of 2-3 layers of rounded cells, nerved. Perichaetial 

 bracts large, membranous, laciniate above. Capsule immersed or 

 exserted, almost sessile, oval-acuminate, oblique, gibbous, narrow- 

 ing upwards to the somewhat recurved lid. Calyptra conical, 

 entire, minute, fugacious ; outer peristome none or rudimentary, 

 inner a pale membrane, exactly as in Buxbaumia, but with only 

 16 plicae. Spores minute. Dioicous. 



1. Diphyscium foliosum Mohr. (Webera sessilis Lindb.j 

 Braithw. Br. M. Fl.) (Tab. XII. C.) 



Plants densely gregarious, dark or brownish green. Stems 

 short ; leaves narrowly Ungulate, variously pointed, obtuse and 

 cucullate, or shortly and bluntly acuminate, crisped when dry, 

 fragile ; margin plane, crenulate-papillose in the upper part, and 

 also at times sinuose or slightly dentate towards apex ; nerve 

 vanishing below the apex, broad and flattened, especially at base, 

 often indistinct. Areolation rounded-quadrate in the upper part 

 of the leaf, strongly papillose on both sides, of 2 or more layers 

 of cells, obscure ; gradually becoming more rectangular and less 

 obscure below, smooth ; towards the base hyaline, rectangular, 

 at margin very thin. Perichaetial bracts very large, the outer 

 resembling the leaves but gradually narrowed from a broader base 

 to a long setaceous point composed of the excurrent nerve, the 

 inner broader, ovate-lanceolate, membranous at margin and white, 

 almost without chlorophyll, at apex lacerate with denticulate cilia, 

 and longly aristate with the excurrent nerve, forming a brown, 

 denticulate hair almost as long as the limb of the leaf ; nerve very 

 broad, golden brown. Capsule almost sessile, hidden by, or 

 slightly emergent from the pericheetial leaves, about the size and 

 with somewhat the aspect of a grain of wheat, golden brown 

 when ripe, asymmetrical, with a curved apex formed by the 

 conical, acute lid ; inner peristome white at the fall of the lid, 

 becoming brown with age. Male plants scattered, minute ; inner 

 bracts ovate, concave, with excurrent nerve. 



Var. p. acutifolium Lindb. Stems taller ; leaves longer, 

 more acuminate and acute. 



Hab. Turfy banks and clefts of rocks in mountainous regions, frequent. Fr. 

 summer. The var. less common, usually barren. 



