446 HYPNACE/E. 



prostrate and procumbent forms, with more or less numerous 

 multiform par aph\< Ilia (oval, lanceolate or laciniate) among the 

 leaves ; branches slender, short, rigid and brittle, sometimes 

 hooked at the tips by the strongly falcate leaves, frequently 

 with paraphyllia but not radiculose. Stem-leaves cordate- 

 triangular, gradually and finely acuminate, erecto-patent or 

 slightly secund; branch-leaves rather narrower, more frequently 

 falcato-secund, often strongly and regularly so and especially 

 falcate at the tips of the branches, rendering them hooked ; all 

 rigid and little altered when dry, not or faintly plicate, 

 strongly decurrent at the narrowed, cordate base, plane at 

 margin or recurved at the base, finely and closely serrulate 

 throughout ; nerve strong, usually yellowish, narrowing above 

 and reaching apex or slightly excurrent, or lost in the acumen. 

 Cells resembling those of the last two species but less incrassate 

 and more variable, elliptic-hexagonal or sometimes linear- 

 rectangular, obtuse at ends and more rounded, less angular, 

 rather smaller; gradually becoming wider and sub- rectangular 

 towards basal angles, then suddenly dilated, hyaline or sometimes 

 orange-brown, sub-rectangular, usually thin-walled, forming 

 clearly marked, decurrent auricles reaching nearly to the nerve. 

 Perichaetial bracts numerous, denticulate, hardly plicate, strongly 

 nerved. Seta long, iy- 2 inches ; capsule sub-cylindrical, rather 

 turgid, arcuate ; lid conical, apiculate. Dioicous. 



Var. fi. Vallisclausse (Hypnum Vallisclausse Brid., sensu 

 Boul. et mult, auct., non Husnot ; Hypnum Formianum Schp., 

 Syn. ?). Stems hardly radiculose, denuded at base, covered with 

 the bristle-like nerves of the older leaves, less regularly pinnate, 

 with fewer, longer branches ; leaves more erect when dry, less 

 strongly and often not at all falcato-secund ; nerve very thick and 

 strong, excurrent in a strong, acute point of varying length ; 

 areolation firm, rather narrow. Paraphyllia few. Aquatic. 



Var. y. gracilescens Schp. Very slender, prostrate, deep 

 green ; stems very tomentose, leaves small. 



Hab. Damp ground, stones and rocks near streams, bogs, etc. , principally in 

 calcareous districts. Common. The var. )8 rare, in calcareous springs ; the var. ■) 

 rare. Fr. spring, but not common. 



A very variable, almost protean plant, yet with a distinct facies and leaf- 

 structure which makes it as a rule easy to recognise, although it is extremely difficult 

 to classify the various forms, many others of which might be enumerated in addition 

 to the above ; but it is doubtful whether even these are more than forms induced by 

 ocal and temporary conditions. I have no authentic specimens of the var. gracilescens 

 Schp. which is recorded in the Lond. Cat. of Brit. Mosses from Yorkshire, but it is 

 probably to be united with the var. trichodes (H. trickodes Brid. ), and includes the 



