404 HYPNACE^E. 



deeper green, soft in texture ; leaves less plicate, broad, longly 

 decurrent with distinct auricles, margin slightly recurved at 

 base. 



Var. y. tenue Dixon n. var. Very slender, almost prostrate, 

 yellowish, branches short, often curved at the tips ; leaves small, 

 distant, widely spreading when dry. 



Var. S. chrysophyllum Spr. Slender, usually yellowish 

 green; leaves glossy, scariose, strongly plicate ; margin reflexed. 



Hab. Rocks and stony places by streams ; often submerged. Frequent. The 

 var. latifolium in alpine streams, rare. The var. tenue, Fairlight Glen, Hastings 

 (Jameson). The var. chrysophyllum rare ; Cannock Chase and Teesdale (Bagnall). 

 Fr. autumn. 



In addition to the dioicous inflorescence, this species differs from B. rutabulum in 

 the more shortly, widely pointed leaves with laxer pellucid basal and angular cells, 

 usually exhibiting distinct, decurrent auricles; the leaves are usually, also, more 

 plicate, more erect and regularly imbricated when dry, less flexuose and spreading ; 

 the plant is, however, very variable in size and habit, as well as in form of leaf. H. 

 latifolium Lindb. is certainly nothing but a variety of this species ; I have frequently 

 gathered intermediate forms with the basal areolation and decurrent angles most 

 strongly marked, but without the peculiar habit of the var. latifoliwn, while on the 

 other hand specimens of that variety do not always show the above structure markedly, 

 the leaves are sometimes plicate, and the margin at base is often plane. I have 

 gathered what seem undoubtedly plants of this variety on Snowdon and on Sea Fell 

 Pike. 



The plant which I have described above as var. tenue is a very marked form, 

 with none of the habit of ordinary B. rivulare ; it is specially characterised by the 

 slender, prostrate habit with narrow, wide-spreading, not erect nor imbricated leaves. 



Several other forms, more or less marked, occur ; when submerged in mountain 

 streams the stems are, as usual under such conditions, elongated and almost simple, 

 the leaves wide, shortly pointed or even almost obtuse, frequently hardly plicate. On 

 the other hand a lowland, marsh form has narrower, rather longly acuminate, deeply 

 plicate leaves. The var. chrysophyllum is very distinct in the margin of the leaves 

 reflexed for a great part of its length, and is a slender, shining form. 



8. Brachythecium Starkei B. & S. (Hypnum StarkeiQr\c\.) 



(Tab. LIJ. M.). 



Stems slender, creeping, radiculose, branches somewhat 

 pinnate, short, distant, ascending, curved, slender ■ forming 

 intricate low patches. Leaves rather loosely imbricated , spread- 

 ing and divergent, not closely imbricated, often secund, widely 

 cordate-triangular , or broadly ovate on the branches, shortly and 

 rather abruptly, but finely acuminate ; not plicate or rarely 

 slightly so when dry; strongly and widely decurrent ; nerve 

 reaching nearly f of the leaf ; margin denticulate, especially 

 above ; cells shorter and wider than in B. rutabulum, narrowly 

 hexagonal-rhomboid, 6-12 times as long as broad, rarely more 

 elongated, often still shorter and wider ; at angles numerous, 

 large, sub-rectangular, pellucid. Seta rough. Perichaetial bracts 



