Jennings: Manual of Mosses 17 



(See also Hygrohypnum) Sematophyllum, p. 283 



98. Stems round, creeping, procumbent or more or less erect, often irregularly 

 stoloniferous; leaves ascending to appressed, often complanate, rarely 

 secund: stem- and branch-leaves dissimilar in the stoloniferous species 

 only, ovate to lanceolate, mostly slenderly ecuminate; costa not often 

 reaching the apex but usually reaching to the middle at least; cells pro- 

 senchymatcus, long rhomboidal to linear-vermicular; operculum conical, 



blunt to long rostrate [Bracbytheciaceae] 120 



98. Branches somewhat complanate; leaves 4-5 mm long, ovate, soft, thin, dry- 

 ing whitish; leaf-cells parenchymatous Hookeria acutijolia, p. 215 



Hypnaceae (99-119) 



99. Costa single, reaching mid-leaf; stem-leaves lance-ovate, rugose, falcate-secund; 

 robust; ends of stem and branches hooked (falcate-secund): leaf-cells dor- 

 sally papillose; lid shortly rostrate Rhytidium, p. 254 



99. If not as above and with costa in our species singk; extending to the middle 



of the leaf or beyond; operculum never rostrate [Amblystegteae] 102 



99. Costa double and usually short, or none; operculum sometimes rostrate 100 



100. Stem and branch leaves usually distinctly dissimilar; leaves symmetric, 

 inserted at right angles to the axis of the stem; branches sometimes 



terete or julaceous [Hylocomieae] 114 



100. Stem and branch leaves quite similar; if minute plantd with median leaf- 

 cells oblong-hexagonal to rhomboidal (about 2-8:1); leaves lanceolate 

 to lance-subulate, see Amblystegiella; leaves often inserted obliquely and 



unsymmetrically 101 



101. Robust, stiff; branching complanately pinnate and plumose; leaves falcate- 

 secund; costa double and short or none Pttlium, p. 259 



101. Leaves either symmetnc and normally inserted or unsymmetric and obliquelv 

 inserted and mostly falcate-secund and smooth; operculum sometimes ros- 

 trate {^Stereodoriteae^ 1 18 



101. Leaves obliquely inserted, mostly two-ranked, mostly unsymmetric but little or 

 not at all secund; branches mostly complanate; operculum conic to short 



rostrate, rarely long-rostrate [Plagiothecicae'] 119 



102. Leaves margined SciaTomwm. p. 234 



102. Leaves not margined 103 



103. Costa strong, ending almost in the apex or sometimes excurrent 104 



103. Costa not extending to the apex of the leaf 109 



104. Paraphyllia numerous and polymorphic 105 



104. Paraphyllia none or very few 106 



105. Leaves deeply longitudinally folded, falcate-secund CratoneitTon. p. 233 



105. Leaves not deeply longitudinally folded Hygroamblyslegutm, p. 230 



106. Leaf-cells linear-vermicular to the leaf-base, mostly with blunt ends, the 

 alar cells forming a small but well defined group of quadrate or rec- 

 tangular cells Hygrohypnum, p. 243 



106. Leaf-cells hexagonal and 2 to 6 times as long as wide, or prolonged- 

 linear and becoming wider and shorter towards the leaf-base, alar cells 



forming a larger group often reaching to the costa 107 



106. Leaf-cells elongate-hexagonal to rhomboid, about 2-6:1; often a few alar 



cells inflated, aquatic or sub-equatic Hygroamblystegium, p. 230 



107. Alar cells parenchymatous; leaves falcate-secund to cirtinate 



Drepanocladus, p. 235 



107. Alar cells prosenchymatous '08 



108. Leaf-cells prolonged; leaves more or less concave Calliergon, p. 240 



108. Leaf-cells prosenchymatous-hexagonal, 2 to 6 times as long as wide 



Hygroamblystegium, p. 230 



109. Leaves cordate- to ovate-lanceolate, more or less acuminate; costa weak, ending 



