. Bulletin of the British Museum (Natural History) Botany. A REVISION OF AFRICAN SPHAGNALES 93. Fig. 7 Sphagnum violascens C. Mull. A, lower lateral area of stem leaf; B, branch leaves (left) and stem leaf (right); C, adaxial surface of branch leaf (right) and abaxial surface (left) from sub-apical leaf region; D, abaxial surface of branch leaf from lower-lateral leaf region (B drawn from the type of S. scotiae; the remainder from Guillaumet 4200). strongly dimorphic. Spreading branches short or much attenuated, 6-0-20-0 mm long; pendent branches paler, narrow and caudiform, finely tapering, 1
. Bulletin of the British Museum (Natural History) Botany. A REVISION OF AFRICAN SPHAGNALES 93. Fig. 7 Sphagnum violascens C. Mull. A, lower lateral area of stem leaf; B, branch leaves (left) and stem leaf (right); C, adaxial surface of branch leaf (right) and abaxial surface (left) from sub-apical leaf region; D, abaxial surface of branch leaf from lower-lateral leaf region (B drawn from the type of S. scotiae; the remainder from Guillaumet 4200). strongly dimorphic. Spreading branches short or much attenuated, 6-0-20-0 mm long; pendent branches paler, narrow and caudiform, finely tapering, 10-0-25-0 mm. Stems 0-6-0-8 mm diameter. Cortex very well developed of (2-)3-4 layers of thin-walled, highly inflated leuco- cysts, the outer series commonly with solitary pores or thinnings; internal cylinder reddish brown to violet-brown. Branch cortex dimorphic, retort cells solitary or in linear pairs (rarely threes). Stem leaves lingulate, variable in attitude but mainly erect or erect-spreading 1-3-1-8 mm long, 0-6-0-8 mm wide: apex abruptly narrowed to a broadly truncate, dentate or more or less erose-fimbriate tip, c. 150-300 urn wide; border 2-4 cells wide above, distinctly to strongly expanded below. Leucocysts variable; in upper part of leaf varying from strongly to weakly fibrillose, or quite devoid of fibrils, strongly fibrillose tissues more or less identical to those of branch leaves, otherwise largely resorbed adaxially and with few abaxial pores. Septa few to numerous, especially in non-fibrillose states. Branch leaves suberect to erect-spreading, unrank- ed or partially to wholly 5-ranked, numerous (60-80 per branch on average) the lower. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original British Museum (Natural History). London : BM(NH)
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