THE EUROPEAN SPHAGNACEX 119 
corresponding pores on the inner surface; pores on the 
outer surface towards the apex sometimes very small and 
ringed, arranged in short, often interrupted rows on the 
commissures ; pores on the inner surface generally very 
merous, in nearly every cell-angle over the wide leaf- 
aunties chlor. jen in section triangular and completely 
enclosed the inner surface ; stem cortex usually not 
clearly differentiated from the wood-cylinder, and hence 
apparently absent . . xx. S. recurvum Russ. & Warnst. 
§ 1v. Sphagna polyclada Russ. Sp. 22. 
15. Branches 7-18 in a fascicle; chlor. cells media 
upper half of the leaf, in section elliptical and eaten a 
the hyaline cells on both sides, in the basal part of the 
leaf barrel. shaped to rectangular and free on a sur- 
§ v. Sphagna rigida 2 2 23. 
15. Branches 3-4 in a fascicle; chlor. cellsin section not median, 
ut nearer the outer surface, elliptical and enclosed on both 
surfaces by the hyaline cells which are united together for 
some distance; inner wall of hyaline cells (in European 
rat: always without papille ; wood-cylinder dark 
brown ; st. 1. small, triangular-lingulate, ee fibrils. 
xxiii. S. compactum DC. 
§ vi, Sphagna truncata Warnst. Sp. 24. 
15. Branches 38-5 i - a fascicle; chlor. cells in section median 
the leaf with ae strongly thickened outer walls free ; 
a those of S. Girgnsin ve he fer the apex broadly 
uncate andrei thed . S. Angstroemit Hartm 
15. brah generally 3-5 in a cite rarely single or 
hlor. cells in section median, barrel-shaped 
or or reatangular to quadrate, free on both surfaces of the 
leaf; inner wall of hyaline cells always without papille ; 
st. 1. either triangular-lingulate and with the border but 
little wider below or of median size to very large, teat: 
SOUEEE ee ee 
