SPHAGNACEAE I 3 



Chlorophyll cells of the branch leaves mostly exposed on both sur- 

 faces; if exposed only on the outer surface, narrowly triangular in 



section 14 



14 — Chlorophyll cells of the branch leaves triangular to rhomboidal in 

 section, with broader exposure on the outer surface, the lumen 



triangular cuspidatum 



Chlorophyll cells of the branch leaves truncately elliptic or rec- 

 tangular to trapezoidal in section, with equal exposure on both 

 surfaces or slightly broader on the inner surface; or, if with broader 

 exposure on the outer surface, the lumen lenticular and central or 



nearly so 15 



15 — Hyaline cells of the branch leaves without fibrils macrophyllum 



Hyaline cells of the branch leaves fibrillose 16 



16 — Chlorophyll cells of the branch leaves exposed equally on both sur- 

 faces or more broadly on the outer one subsecundum 



Chlorophyll cells of the branch leaves usually exposed a little more 



broadly on the inner surface 17 



17 — Pores on the outer surface of the branch leaves if present, never 



more than 2 to each cell Pylaesii 



Pores on the outer surface of the branch or stem leaves always 



more than two to each cell cyclophylhim 



18 — Stem leaves fimbriate-lacerate in the apical part 19 



Stem leaves not notably lacerate in the apical part 20 



19 — Lacerate at both sides and apex fimbriatum 



Lacerate only across the broad truncate apex Girgensohnii 



20 — Hyaline cells of the branch leaves smaller, their free convexity on 



the outer surface mostly less than }4 their diameter 21 



Hyaline cells of the branch leaves large in section, their free con- 

 vexity on the outer surface usually more than half their diameter. .23 



21 — Pigment brown fuscum 



Pigment red 22 



22 — Outer surface of the branch leaves with very small round strongly 



ringed pores in the apical part Warnstorfii 



Outer surface of the branch leaves with much larger elliptic pores. 



capillaceum 



23 — Pigment brown, sometimes passing to purplish plumulosum 



Pigment red 24 



24 — Margin of the branch leaves entire tenerum 



Margin of the branch leaves denticulate tabulare 



S. erythrocalyx Hampe is reported from New Jersey in N. Am. Flora. It is 

 distinguishable from 5. papillosum by not having papillae on the chlorophyll 

 cells of the branch leaves. 



5. quinquefarium (Lindb.) Warnst. should be found. It is distinguished 

 from 5. capillaceum by having its leaves mostly as broad as long instead of 

 \ l A or more times as long as broad. 



