58 DICRANACE/E. 



lanceolate-subulate point ; margin slightly thickened, recurved 

 from a little above the base to near the apex, faintly denticulate 

 above; nerve slightly excurrent, toothed at apex; areolation 

 hexagonal-rectangular at base, chlorophyllose, irregularly rhom- 

 boid or quadrate above. Perichsetial bracts resembling the 

 leaves, but longer, sheathing. Seta red. Capsule erect, 

 narrowly or oblong-cylindrical, pale brown ; annulus broad, of a 

 single row of cells ; lid longer than in the last, conical-rostellate. 

 Peristome teeth red, the divisions here and there united. 

 Dioicous ; male plants short, bracts ovate-subulate. 



Var. /?. pusillum Braithw. (Trichostomum pusillum Hedw.). 

 Stems more densely crowded, shorter. Leaves shorter, broader ; 

 capsule oval or oblong, peristome shorter. Perichaetial bracts 

 with a shorter point. 



Hab. Sandy banks and quarries, rare. Yorkshire, Sussex, Kent. The var. j8 

 in similar habitats, sometimes with the type. Ireland, Yorkshire, Scotland. Fr. 

 winter. 



This species is very variable in the form and size of the capsules ; I have seen 

 them on the same tuft from cylindrical to very shortly ovate, indeed (without the lid) 

 hardly longer than broad ; the var. B cannot therefore be considered a clearly defined 

 form. The leaves are shorter than in the next two species, with the upper cells wider 

 and shorter, and are also more denticulate, wider in the middle, with the margin re- 

 curved. It also varies in the length of the leaves ; these are sometimes very short, 

 and in proportion to their size, broad, with the lamina distinct to the apex ; especially 

 in some forms of the var. pusillum, which have been recorded as a separate species by 

 Schimper and others under the name of Leptotrichum vaginans Sull. ; this however 

 appears to be an error, the true L. vaginans Sull. being a different plant. 



3. Ditrichum homomallum Hampe (Didymodon homomallus 



Hedw. ; Leptotrichum homomallum Hampe, Schp. Syn.) 



(Tab. XII. J.). 



Plants (in the type) loosely tufted, somewhat silky, pale or 

 yellowish green, short, stem simple or nearly so, ^-inch high. 

 Leaves glossy, subsecund, from an oval or narrowly triangular 

 base, gradually lanceolate-subulate ; margin plane; nerve 

 broad, rather indistinct, excurrent, with a few minute denticula- 

 tions at apex ; areolation very narrow, linear or rectangular, 

 firm, not much shorter above, chlorophyllose. Perichaetial bracts 

 longer, sheathing. Seta straight, purple. Capsule ovate-oblong 

 or oblong, pachydermous, darker red, shining, somewhat 

 narrowed at mouth ; lid conical or conical-rostellate, obtuse. 

 Annulus of two rows of cells. Peristome purplish, the basal 

 membrane indistinct, teeth with the divisions free or united. 

 Dioicous ; male plants slender ; bracts lanceolate-subulate. 



