ft DICRANACE/E. 



1. Dichodontium pellucidum Schp. (Bryum pellucidum L.) 



(Tab. XIV. J.). 



Pale or dull green, in rather lax tufts, 1-3 inches high. 

 Stems slightly branched, flexuose, radiculose below. Leaves 

 variously imbricated, but never very densely placed, recurved and 

 spreading or squarrose from a more erect base, appressed and 

 twisted when dry, varying greatly in length and width, from a 

 broad, oval or oblong base narrowed into a lo.nger or shorter 

 oblong-lingulate, broad, concave limb, rounded and obtuse or 

 obtusely pointed ; margin recurved below, somewhat undulated 

 above, incurved at apex, almost entire or more frequently crenu- 

 late-serrate towards the summit, limb opaque, studded with 

 sharp, ascending papilla? on both sides ; cells at base elongated, 

 narrowly rectangular, rather pellucid, with several rows at the 

 margin to the base shorter and chlorophyllose, in the upper part 

 small, irregularly quadrate or rounded, obscure. Nerve thick, 

 vanishing below apex, rough with denticulations at back above. 

 Dioicous. Fruitstalk short, thick, especially towards the top, 

 reddish yellow ; capsule short, oval or subglobose, cernuous, some- 

 what gibbous, with hardly any neck, but tapering at base into the 

 fruitstalk, smooth, solid in texture, purplish brown, exannulate ; 

 lid obliquely and shortly rostrate, rather thick. Peristome large, 

 deep red, the teeth 2-3 cleft, papillose at apex, vertically striate 

 below, from a rather high basal membrane. 



Var. /3. fagimontanum Schp. (Dicranum pellucidum var. 

 fagimontanum Brid.). Shorter, with shorter branches ; leaves 

 short, more obtuse, hardly spreading ; capsule smaller. 



Var. y. strictum Braithw. Stems densely tufted, elongated, 

 slender, straight. Leaves distant, very short, suddenly con- 

 tracted to a narrow-Ungulate channelled limb, tapering to an 

 obtuse almost entire point. 



Var. S. compactum Schp. Stems very densely tufted, reddish 

 brown below, very slender ; leaves smaller, short. 



Hab. Wet rocks or sandy dibris near streams ; common in mountainous dis- 

 tricts, not common elsewhere. The var. £ in more alpine districts ; Ben Lawers, &c. 

 The var. y among grass, near Abergavenny. The var. 8 Scotland ; South Wales. Fr. 

 autumn to spring. 



A variable plant, but when once known recognised without much difficulty by the 

 form and structure of the leaves. The short, broadly pointed, obtuse leaves dis- 

 tinguish the var. fagimontanum from the type. The fruit is not very commonly pro- 

 duced, and the fertile plant is usually rather smaller and more slender. In the forms 

 with short leaves the basal cells are generally shorter and more uniform, less pellucid- 



